1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Linux Socket Filter - Kernel level socket filtering
4 *
5 * Based on the design of the Berkeley Packet Filter. The new
6 * internal format has been designed by PLUMgrid:
7 *
8 * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
9 *
10 * Authors:
11 *
12 * Jay Schulist <jschlst@samba.org>
13 * Alexei Starovoitov <ast@plumgrid.com>
14 * Daniel Borkmann <dborkman@redhat.com>
15 *
16 * Andi Kleen - Fix a few bad bugs and races.
17 * Kris Katterjohn - Added many additional checks in bpf_check_classic()
18 */
19
20 #include <linux/module.h>
21 #include <linux/types.h>
22 #include <linux/mm.h>
23 #include <linux/fcntl.h>
24 #include <linux/socket.h>
25 #include <linux/sock_diag.h>
26 #include <linux/in.h>
27 #include <linux/inet.h>
28 #include <linux/netdevice.h>
29 #include <linux/if_packet.h>
30 #include <linux/if_arp.h>
31 #include <linux/gfp.h>
32 #include <net/inet_common.h>
33 #include <net/ip.h>
34 #include <net/protocol.h>
35 #include <net/netlink.h>
36 #include <linux/skbuff.h>
37 #include <linux/skmsg.h>
38 #include <net/sock.h>
39 #include <net/flow_dissector.h>
40 #include <linux/errno.h>
41 #include <linux/timer.h>
42 #include <linux/uaccess.h>
43 #include <asm/unaligned.h>
44 #include <asm/cmpxchg.h>
45 #include <linux/filter.h>
46 #include <linux/ratelimit.h>
47 #include <linux/seccomp.h>
48 #include <linux/if_vlan.h>
49 #include <linux/bpf.h>
50 #include <net/sch_generic.h>
51 #include <net/cls_cgroup.h>
52 #include <net/dst_metadata.h>
53 #include <net/dst.h>
54 #include <net/sock_reuseport.h>
55 #include <net/busy_poll.h>
56 #include <net/tcp.h>
57 #include <net/xfrm.h>
58 #include <net/udp.h>
59 #include <linux/bpf_trace.h>
60 #include <net/xdp_sock.h>
61 #include <linux/inetdevice.h>
62 #include <net/inet_hashtables.h>
63 #include <net/inet6_hashtables.h>
64 #include <net/ip_fib.h>
65 #include <net/nexthop.h>
66 #include <net/flow.h>
67 #include <net/arp.h>
68 #include <net/ipv6.h>
69 #include <net/net_namespace.h>
70 #include <linux/seg6_local.h>
71 #include <net/seg6.h>
72 #include <net/seg6_local.h>
73 #include <net/lwtunnel.h>
74 #include <net/ipv6_stubs.h>
75 #include <net/bpf_sk_storage.h>
76
77 /**
78 * sk_filter_trim_cap - run a packet through a socket filter
79 * @sk: sock associated with &sk_buff
80 * @skb: buffer to filter
81 * @cap: limit on how short the eBPF program may trim the packet
82 *
83 * Run the eBPF program and then cut skb->data to correct size returned by
84 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
85 * than pkt_len we keep whole skb->data. This is the socket level
86 * wrapper to BPF_PROG_RUN. It returns 0 if the packet should
87 * be accepted or -EPERM if the packet should be tossed.
88 *
89 */
sk_filter_trim_cap(struct sock * sk,struct sk_buff * skb,unsigned int cap)90 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
91 {
92 int err;
93 struct sk_filter *filter;
94
95 /*
96 * If the skb was allocated from pfmemalloc reserves, only
97 * allow SOCK_MEMALLOC sockets to use it as this socket is
98 * helping free memory
99 */
100 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
101 NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
102 return -ENOMEM;
103 }
104 err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
105 if (err)
106 return err;
107
108 err = security_sock_rcv_skb(sk, skb);
109 if (err)
110 return err;
111
112 rcu_read_lock();
113 filter = rcu_dereference(sk->sk_filter);
114 if (filter) {
115 struct sock *save_sk = skb->sk;
116 unsigned int pkt_len;
117
118 skb->sk = sk;
119 pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
120 skb->sk = save_sk;
121 err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
122 }
123 rcu_read_unlock();
124
125 return err;
126 }
127 EXPORT_SYMBOL(sk_filter_trim_cap);
128
BPF_CALL_1(bpf_skb_get_pay_offset,struct sk_buff *,skb)129 BPF_CALL_1(bpf_skb_get_pay_offset, struct sk_buff *, skb)
130 {
131 return skb_get_poff(skb);
132 }
133
BPF_CALL_3(bpf_skb_get_nlattr,struct sk_buff *,skb,u32,a,u32,x)134 BPF_CALL_3(bpf_skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
135 {
136 struct nlattr *nla;
137
138 if (skb_is_nonlinear(skb))
139 return 0;
140
141 if (skb->len < sizeof(struct nlattr))
142 return 0;
143
144 if (a > skb->len - sizeof(struct nlattr))
145 return 0;
146
147 nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
148 if (nla)
149 return (void *) nla - (void *) skb->data;
150
151 return 0;
152 }
153
BPF_CALL_3(bpf_skb_get_nlattr_nest,struct sk_buff *,skb,u32,a,u32,x)154 BPF_CALL_3(bpf_skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
155 {
156 struct nlattr *nla;
157
158 if (skb_is_nonlinear(skb))
159 return 0;
160
161 if (skb->len < sizeof(struct nlattr))
162 return 0;
163
164 if (a > skb->len - sizeof(struct nlattr))
165 return 0;
166
167 nla = (struct nlattr *) &skb->data[a];
168 if (nla->nla_len > skb->len - a)
169 return 0;
170
171 nla = nla_find_nested(nla, x);
172 if (nla)
173 return (void *) nla - (void *) skb->data;
174
175 return 0;
176 }
177
BPF_CALL_4(bpf_skb_load_helper_8,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)178 BPF_CALL_4(bpf_skb_load_helper_8, const struct sk_buff *, skb, const void *,
179 data, int, headlen, int, offset)
180 {
181 u8 tmp, *ptr;
182 const int len = sizeof(tmp);
183
184 if (offset >= 0) {
185 if (headlen - offset >= len)
186 return *(u8 *)(data + offset);
187 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
188 return tmp;
189 } else {
190 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
191 if (likely(ptr))
192 return *(u8 *)ptr;
193 }
194
195 return -EFAULT;
196 }
197
BPF_CALL_2(bpf_skb_load_helper_8_no_cache,const struct sk_buff *,skb,int,offset)198 BPF_CALL_2(bpf_skb_load_helper_8_no_cache, const struct sk_buff *, skb,
199 int, offset)
200 {
201 return ____bpf_skb_load_helper_8(skb, skb->data, skb->len - skb->data_len,
202 offset);
203 }
204
BPF_CALL_4(bpf_skb_load_helper_16,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)205 BPF_CALL_4(bpf_skb_load_helper_16, const struct sk_buff *, skb, const void *,
206 data, int, headlen, int, offset)
207 {
208 u16 tmp, *ptr;
209 const int len = sizeof(tmp);
210
211 if (offset >= 0) {
212 if (headlen - offset >= len)
213 return get_unaligned_be16(data + offset);
214 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
215 return be16_to_cpu(tmp);
216 } else {
217 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
218 if (likely(ptr))
219 return get_unaligned_be16(ptr);
220 }
221
222 return -EFAULT;
223 }
224
BPF_CALL_2(bpf_skb_load_helper_16_no_cache,const struct sk_buff *,skb,int,offset)225 BPF_CALL_2(bpf_skb_load_helper_16_no_cache, const struct sk_buff *, skb,
226 int, offset)
227 {
228 return ____bpf_skb_load_helper_16(skb, skb->data, skb->len - skb->data_len,
229 offset);
230 }
231
BPF_CALL_4(bpf_skb_load_helper_32,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)232 BPF_CALL_4(bpf_skb_load_helper_32, const struct sk_buff *, skb, const void *,
233 data, int, headlen, int, offset)
234 {
235 u32 tmp, *ptr;
236 const int len = sizeof(tmp);
237
238 if (likely(offset >= 0)) {
239 if (headlen - offset >= len)
240 return get_unaligned_be32(data + offset);
241 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
242 return be32_to_cpu(tmp);
243 } else {
244 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
245 if (likely(ptr))
246 return get_unaligned_be32(ptr);
247 }
248
249 return -EFAULT;
250 }
251
BPF_CALL_2(bpf_skb_load_helper_32_no_cache,const struct sk_buff *,skb,int,offset)252 BPF_CALL_2(bpf_skb_load_helper_32_no_cache, const struct sk_buff *, skb,
253 int, offset)
254 {
255 return ____bpf_skb_load_helper_32(skb, skb->data, skb->len - skb->data_len,
256 offset);
257 }
258
BPF_CALL_0(bpf_get_raw_cpu_id)259 BPF_CALL_0(bpf_get_raw_cpu_id)
260 {
261 return raw_smp_processor_id();
262 }
263
264 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = {
265 .func = bpf_get_raw_cpu_id,
266 .gpl_only = false,
267 .ret_type = RET_INTEGER,
268 };
269
convert_skb_access(int skb_field,int dst_reg,int src_reg,struct bpf_insn * insn_buf)270 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
271 struct bpf_insn *insn_buf)
272 {
273 struct bpf_insn *insn = insn_buf;
274
275 switch (skb_field) {
276 case SKF_AD_MARK:
277 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4);
278
279 *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
280 offsetof(struct sk_buff, mark));
281 break;
282
283 case SKF_AD_PKTTYPE:
284 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET());
285 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
286 #ifdef __BIG_ENDIAN_BITFIELD
287 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
288 #endif
289 break;
290
291 case SKF_AD_QUEUE:
292 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2);
293
294 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
295 offsetof(struct sk_buff, queue_mapping));
296 break;
297
298 case SKF_AD_VLAN_TAG:
299 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
300
301 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
302 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
303 offsetof(struct sk_buff, vlan_tci));
304 break;
305 case SKF_AD_VLAN_TAG_PRESENT:
306 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_VLAN_PRESENT_OFFSET());
307 if (PKT_VLAN_PRESENT_BIT)
308 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, PKT_VLAN_PRESENT_BIT);
309 if (PKT_VLAN_PRESENT_BIT < 7)
310 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
311 break;
312 }
313
314 return insn - insn_buf;
315 }
316
convert_bpf_extensions(struct sock_filter * fp,struct bpf_insn ** insnp)317 static bool convert_bpf_extensions(struct sock_filter *fp,
318 struct bpf_insn **insnp)
319 {
320 struct bpf_insn *insn = *insnp;
321 u32 cnt;
322
323 switch (fp->k) {
324 case SKF_AD_OFF + SKF_AD_PROTOCOL:
325 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2);
326
327 /* A = *(u16 *) (CTX + offsetof(protocol)) */
328 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
329 offsetof(struct sk_buff, protocol));
330 /* A = ntohs(A) [emitting a nop or swap16] */
331 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
332 break;
333
334 case SKF_AD_OFF + SKF_AD_PKTTYPE:
335 cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
336 insn += cnt - 1;
337 break;
338
339 case SKF_AD_OFF + SKF_AD_IFINDEX:
340 case SKF_AD_OFF + SKF_AD_HATYPE:
341 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4);
342 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2);
343
344 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
345 BPF_REG_TMP, BPF_REG_CTX,
346 offsetof(struct sk_buff, dev));
347 /* if (tmp != 0) goto pc + 1 */
348 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
349 *insn++ = BPF_EXIT_INSN();
350 if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
351 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
352 offsetof(struct net_device, ifindex));
353 else
354 *insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
355 offsetof(struct net_device, type));
356 break;
357
358 case SKF_AD_OFF + SKF_AD_MARK:
359 cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
360 insn += cnt - 1;
361 break;
362
363 case SKF_AD_OFF + SKF_AD_RXHASH:
364 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4);
365
366 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
367 offsetof(struct sk_buff, hash));
368 break;
369
370 case SKF_AD_OFF + SKF_AD_QUEUE:
371 cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
372 insn += cnt - 1;
373 break;
374
375 case SKF_AD_OFF + SKF_AD_VLAN_TAG:
376 cnt = convert_skb_access(SKF_AD_VLAN_TAG,
377 BPF_REG_A, BPF_REG_CTX, insn);
378 insn += cnt - 1;
379 break;
380
381 case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
382 cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
383 BPF_REG_A, BPF_REG_CTX, insn);
384 insn += cnt - 1;
385 break;
386
387 case SKF_AD_OFF + SKF_AD_VLAN_TPID:
388 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_proto) != 2);
389
390 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
391 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
392 offsetof(struct sk_buff, vlan_proto));
393 /* A = ntohs(A) [emitting a nop or swap16] */
394 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
395 break;
396
397 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
398 case SKF_AD_OFF + SKF_AD_NLATTR:
399 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
400 case SKF_AD_OFF + SKF_AD_CPU:
401 case SKF_AD_OFF + SKF_AD_RANDOM:
402 /* arg1 = CTX */
403 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
404 /* arg2 = A */
405 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
406 /* arg3 = X */
407 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
408 /* Emit call(arg1=CTX, arg2=A, arg3=X) */
409 switch (fp->k) {
410 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
411 *insn = BPF_EMIT_CALL(bpf_skb_get_pay_offset);
412 break;
413 case SKF_AD_OFF + SKF_AD_NLATTR:
414 *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr);
415 break;
416 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
417 *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr_nest);
418 break;
419 case SKF_AD_OFF + SKF_AD_CPU:
420 *insn = BPF_EMIT_CALL(bpf_get_raw_cpu_id);
421 break;
422 case SKF_AD_OFF + SKF_AD_RANDOM:
423 *insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
424 bpf_user_rnd_init_once();
425 break;
426 }
427 break;
428
429 case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
430 /* A ^= X */
431 *insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
432 break;
433
434 default:
435 /* This is just a dummy call to avoid letting the compiler
436 * evict __bpf_call_base() as an optimization. Placed here
437 * where no-one bothers.
438 */
439 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
440 return false;
441 }
442
443 *insnp = insn;
444 return true;
445 }
446
convert_bpf_ld_abs(struct sock_filter * fp,struct bpf_insn ** insnp)447 static bool convert_bpf_ld_abs(struct sock_filter *fp, struct bpf_insn **insnp)
448 {
449 const bool unaligned_ok = IS_BUILTIN(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS);
450 int size = bpf_size_to_bytes(BPF_SIZE(fp->code));
451 bool endian = BPF_SIZE(fp->code) == BPF_H ||
452 BPF_SIZE(fp->code) == BPF_W;
453 bool indirect = BPF_MODE(fp->code) == BPF_IND;
454 const int ip_align = NET_IP_ALIGN;
455 struct bpf_insn *insn = *insnp;
456 int offset = fp->k;
457
458 if (!indirect &&
459 ((unaligned_ok && offset >= 0) ||
460 (!unaligned_ok && offset >= 0 &&
461 offset + ip_align >= 0 &&
462 offset + ip_align % size == 0))) {
463 bool ldx_off_ok = offset <= S16_MAX;
464
465 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_H);
466 if (offset)
467 *insn++ = BPF_ALU64_IMM(BPF_SUB, BPF_REG_TMP, offset);
468 *insn++ = BPF_JMP_IMM(BPF_JSLT, BPF_REG_TMP,
469 size, 2 + endian + (!ldx_off_ok * 2));
470 if (ldx_off_ok) {
471 *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
472 BPF_REG_D, offset);
473 } else {
474 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_D);
475 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_TMP, offset);
476 *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
477 BPF_REG_TMP, 0);
478 }
479 if (endian)
480 *insn++ = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, size * 8);
481 *insn++ = BPF_JMP_A(8);
482 }
483
484 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
485 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_D);
486 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_H);
487 if (!indirect) {
488 *insn++ = BPF_MOV64_IMM(BPF_REG_ARG4, offset);
489 } else {
490 *insn++ = BPF_MOV64_REG(BPF_REG_ARG4, BPF_REG_X);
491 if (fp->k)
492 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG4, offset);
493 }
494
495 switch (BPF_SIZE(fp->code)) {
496 case BPF_B:
497 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8);
498 break;
499 case BPF_H:
500 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16);
501 break;
502 case BPF_W:
503 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32);
504 break;
505 default:
506 return false;
507 }
508
509 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_A, 0, 2);
510 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
511 *insn = BPF_EXIT_INSN();
512
513 *insnp = insn;
514 return true;
515 }
516
517 /**
518 * bpf_convert_filter - convert filter program
519 * @prog: the user passed filter program
520 * @len: the length of the user passed filter program
521 * @new_prog: allocated 'struct bpf_prog' or NULL
522 * @new_len: pointer to store length of converted program
523 * @seen_ld_abs: bool whether we've seen ld_abs/ind
524 *
525 * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
526 * style extended BPF (eBPF).
527 * Conversion workflow:
528 *
529 * 1) First pass for calculating the new program length:
530 * bpf_convert_filter(old_prog, old_len, NULL, &new_len, &seen_ld_abs)
531 *
532 * 2) 2nd pass to remap in two passes: 1st pass finds new
533 * jump offsets, 2nd pass remapping:
534 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len, &seen_ld_abs)
535 */
bpf_convert_filter(struct sock_filter * prog,int len,struct bpf_prog * new_prog,int * new_len,bool * seen_ld_abs)536 static int bpf_convert_filter(struct sock_filter *prog, int len,
537 struct bpf_prog *new_prog, int *new_len,
538 bool *seen_ld_abs)
539 {
540 int new_flen = 0, pass = 0, target, i, stack_off;
541 struct bpf_insn *new_insn, *first_insn = NULL;
542 struct sock_filter *fp;
543 int *addrs = NULL;
544 u8 bpf_src;
545
546 BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
547 BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
548
549 if (len <= 0 || len > BPF_MAXINSNS)
550 return -EINVAL;
551
552 if (new_prog) {
553 first_insn = new_prog->insnsi;
554 addrs = kcalloc(len, sizeof(*addrs),
555 GFP_KERNEL | __GFP_NOWARN);
556 if (!addrs)
557 return -ENOMEM;
558 }
559
560 do_pass:
561 new_insn = first_insn;
562 fp = prog;
563
564 /* Classic BPF related prologue emission. */
565 if (new_prog) {
566 /* Classic BPF expects A and X to be reset first. These need
567 * to be guaranteed to be the first two instructions.
568 */
569 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
570 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
571
572 /* All programs must keep CTX in callee saved BPF_REG_CTX.
573 * In eBPF case it's done by the compiler, here we need to
574 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
575 */
576 *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
577 if (*seen_ld_abs) {
578 /* For packet access in classic BPF, cache skb->data
579 * in callee-saved BPF R8 and skb->len - skb->data_len
580 * (headlen) in BPF R9. Since classic BPF is read-only
581 * on CTX, we only need to cache it once.
582 */
583 *new_insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
584 BPF_REG_D, BPF_REG_CTX,
585 offsetof(struct sk_buff, data));
586 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_H, BPF_REG_CTX,
587 offsetof(struct sk_buff, len));
588 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_TMP, BPF_REG_CTX,
589 offsetof(struct sk_buff, data_len));
590 *new_insn++ = BPF_ALU32_REG(BPF_SUB, BPF_REG_H, BPF_REG_TMP);
591 }
592 } else {
593 new_insn += 3;
594 }
595
596 for (i = 0; i < len; fp++, i++) {
597 struct bpf_insn tmp_insns[32] = { };
598 struct bpf_insn *insn = tmp_insns;
599
600 if (addrs)
601 addrs[i] = new_insn - first_insn;
602
603 switch (fp->code) {
604 /* All arithmetic insns and skb loads map as-is. */
605 case BPF_ALU | BPF_ADD | BPF_X:
606 case BPF_ALU | BPF_ADD | BPF_K:
607 case BPF_ALU | BPF_SUB | BPF_X:
608 case BPF_ALU | BPF_SUB | BPF_K:
609 case BPF_ALU | BPF_AND | BPF_X:
610 case BPF_ALU | BPF_AND | BPF_K:
611 case BPF_ALU | BPF_OR | BPF_X:
612 case BPF_ALU | BPF_OR | BPF_K:
613 case BPF_ALU | BPF_LSH | BPF_X:
614 case BPF_ALU | BPF_LSH | BPF_K:
615 case BPF_ALU | BPF_RSH | BPF_X:
616 case BPF_ALU | BPF_RSH | BPF_K:
617 case BPF_ALU | BPF_XOR | BPF_X:
618 case BPF_ALU | BPF_XOR | BPF_K:
619 case BPF_ALU | BPF_MUL | BPF_X:
620 case BPF_ALU | BPF_MUL | BPF_K:
621 case BPF_ALU | BPF_DIV | BPF_X:
622 case BPF_ALU | BPF_DIV | BPF_K:
623 case BPF_ALU | BPF_MOD | BPF_X:
624 case BPF_ALU | BPF_MOD | BPF_K:
625 case BPF_ALU | BPF_NEG:
626 case BPF_LD | BPF_ABS | BPF_W:
627 case BPF_LD | BPF_ABS | BPF_H:
628 case BPF_LD | BPF_ABS | BPF_B:
629 case BPF_LD | BPF_IND | BPF_W:
630 case BPF_LD | BPF_IND | BPF_H:
631 case BPF_LD | BPF_IND | BPF_B:
632 /* Check for overloaded BPF extension and
633 * directly convert it if found, otherwise
634 * just move on with mapping.
635 */
636 if (BPF_CLASS(fp->code) == BPF_LD &&
637 BPF_MODE(fp->code) == BPF_ABS &&
638 convert_bpf_extensions(fp, &insn))
639 break;
640 if (BPF_CLASS(fp->code) == BPF_LD &&
641 convert_bpf_ld_abs(fp, &insn)) {
642 *seen_ld_abs = true;
643 break;
644 }
645
646 if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) ||
647 fp->code == (BPF_ALU | BPF_MOD | BPF_X)) {
648 *insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X);
649 /* Error with exception code on div/mod by 0.
650 * For cBPF programs, this was always return 0.
651 */
652 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2);
653 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
654 *insn++ = BPF_EXIT_INSN();
655 }
656
657 *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
658 break;
659
660 /* Jump transformation cannot use BPF block macros
661 * everywhere as offset calculation and target updates
662 * require a bit more work than the rest, i.e. jump
663 * opcodes map as-is, but offsets need adjustment.
664 */
665
666 #define BPF_EMIT_JMP \
667 do { \
668 const s32 off_min = S16_MIN, off_max = S16_MAX; \
669 s32 off; \
670 \
671 if (target >= len || target < 0) \
672 goto err; \
673 off = addrs ? addrs[target] - addrs[i] - 1 : 0; \
674 /* Adjust pc relative offset for 2nd or 3rd insn. */ \
675 off -= insn - tmp_insns; \
676 /* Reject anything not fitting into insn->off. */ \
677 if (off < off_min || off > off_max) \
678 goto err; \
679 insn->off = off; \
680 } while (0)
681
682 case BPF_JMP | BPF_JA:
683 target = i + fp->k + 1;
684 insn->code = fp->code;
685 BPF_EMIT_JMP;
686 break;
687
688 case BPF_JMP | BPF_JEQ | BPF_K:
689 case BPF_JMP | BPF_JEQ | BPF_X:
690 case BPF_JMP | BPF_JSET | BPF_K:
691 case BPF_JMP | BPF_JSET | BPF_X:
692 case BPF_JMP | BPF_JGT | BPF_K:
693 case BPF_JMP | BPF_JGT | BPF_X:
694 case BPF_JMP | BPF_JGE | BPF_K:
695 case BPF_JMP | BPF_JGE | BPF_X:
696 if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
697 /* BPF immediates are signed, zero extend
698 * immediate into tmp register and use it
699 * in compare insn.
700 */
701 *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
702
703 insn->dst_reg = BPF_REG_A;
704 insn->src_reg = BPF_REG_TMP;
705 bpf_src = BPF_X;
706 } else {
707 insn->dst_reg = BPF_REG_A;
708 insn->imm = fp->k;
709 bpf_src = BPF_SRC(fp->code);
710 insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
711 }
712
713 /* Common case where 'jump_false' is next insn. */
714 if (fp->jf == 0) {
715 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
716 target = i + fp->jt + 1;
717 BPF_EMIT_JMP;
718 break;
719 }
720
721 /* Convert some jumps when 'jump_true' is next insn. */
722 if (fp->jt == 0) {
723 switch (BPF_OP(fp->code)) {
724 case BPF_JEQ:
725 insn->code = BPF_JMP | BPF_JNE | bpf_src;
726 break;
727 case BPF_JGT:
728 insn->code = BPF_JMP | BPF_JLE | bpf_src;
729 break;
730 case BPF_JGE:
731 insn->code = BPF_JMP | BPF_JLT | bpf_src;
732 break;
733 default:
734 goto jmp_rest;
735 }
736
737 target = i + fp->jf + 1;
738 BPF_EMIT_JMP;
739 break;
740 }
741 jmp_rest:
742 /* Other jumps are mapped into two insns: Jxx and JA. */
743 target = i + fp->jt + 1;
744 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
745 BPF_EMIT_JMP;
746 insn++;
747
748 insn->code = BPF_JMP | BPF_JA;
749 target = i + fp->jf + 1;
750 BPF_EMIT_JMP;
751 break;
752
753 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
754 case BPF_LDX | BPF_MSH | BPF_B: {
755 struct sock_filter tmp = {
756 .code = BPF_LD | BPF_ABS | BPF_B,
757 .k = fp->k,
758 };
759
760 *seen_ld_abs = true;
761
762 /* X = A */
763 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
764 /* A = BPF_R0 = *(u8 *) (skb->data + K) */
765 convert_bpf_ld_abs(&tmp, &insn);
766 insn++;
767 /* A &= 0xf */
768 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
769 /* A <<= 2 */
770 *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
771 /* tmp = X */
772 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_X);
773 /* X = A */
774 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
775 /* A = tmp */
776 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
777 break;
778 }
779 /* RET_K is remaped into 2 insns. RET_A case doesn't need an
780 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
781 */
782 case BPF_RET | BPF_A:
783 case BPF_RET | BPF_K:
784 if (BPF_RVAL(fp->code) == BPF_K)
785 *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
786 0, fp->k);
787 *insn = BPF_EXIT_INSN();
788 break;
789
790 /* Store to stack. */
791 case BPF_ST:
792 case BPF_STX:
793 stack_off = fp->k * 4 + 4;
794 *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
795 BPF_ST ? BPF_REG_A : BPF_REG_X,
796 -stack_off);
797 /* check_load_and_stores() verifies that classic BPF can
798 * load from stack only after write, so tracking
799 * stack_depth for ST|STX insns is enough
800 */
801 if (new_prog && new_prog->aux->stack_depth < stack_off)
802 new_prog->aux->stack_depth = stack_off;
803 break;
804
805 /* Load from stack. */
806 case BPF_LD | BPF_MEM:
807 case BPF_LDX | BPF_MEM:
808 stack_off = fp->k * 4 + 4;
809 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
810 BPF_REG_A : BPF_REG_X, BPF_REG_FP,
811 -stack_off);
812 break;
813
814 /* A = K or X = K */
815 case BPF_LD | BPF_IMM:
816 case BPF_LDX | BPF_IMM:
817 *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
818 BPF_REG_A : BPF_REG_X, fp->k);
819 break;
820
821 /* X = A */
822 case BPF_MISC | BPF_TAX:
823 *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
824 break;
825
826 /* A = X */
827 case BPF_MISC | BPF_TXA:
828 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
829 break;
830
831 /* A = skb->len or X = skb->len */
832 case BPF_LD | BPF_W | BPF_LEN:
833 case BPF_LDX | BPF_W | BPF_LEN:
834 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
835 BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
836 offsetof(struct sk_buff, len));
837 break;
838
839 /* Access seccomp_data fields. */
840 case BPF_LDX | BPF_ABS | BPF_W:
841 /* A = *(u32 *) (ctx + K) */
842 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
843 break;
844
845 /* Unknown instruction. */
846 default:
847 goto err;
848 }
849
850 insn++;
851 if (new_prog)
852 memcpy(new_insn, tmp_insns,
853 sizeof(*insn) * (insn - tmp_insns));
854 new_insn += insn - tmp_insns;
855 }
856
857 if (!new_prog) {
858 /* Only calculating new length. */
859 *new_len = new_insn - first_insn;
860 if (*seen_ld_abs)
861 *new_len += 4; /* Prologue bits. */
862 return 0;
863 }
864
865 pass++;
866 if (new_flen != new_insn - first_insn) {
867 new_flen = new_insn - first_insn;
868 if (pass > 2)
869 goto err;
870 goto do_pass;
871 }
872
873 kfree(addrs);
874 BUG_ON(*new_len != new_flen);
875 return 0;
876 err:
877 kfree(addrs);
878 return -EINVAL;
879 }
880
881 /* Security:
882 *
883 * As we dont want to clear mem[] array for each packet going through
884 * __bpf_prog_run(), we check that filter loaded by user never try to read
885 * a cell if not previously written, and we check all branches to be sure
886 * a malicious user doesn't try to abuse us.
887 */
check_load_and_stores(const struct sock_filter * filter,int flen)888 static int check_load_and_stores(const struct sock_filter *filter, int flen)
889 {
890 u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
891 int pc, ret = 0;
892
893 BUILD_BUG_ON(BPF_MEMWORDS > 16);
894
895 masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
896 if (!masks)
897 return -ENOMEM;
898
899 memset(masks, 0xff, flen * sizeof(*masks));
900
901 for (pc = 0; pc < flen; pc++) {
902 memvalid &= masks[pc];
903
904 switch (filter[pc].code) {
905 case BPF_ST:
906 case BPF_STX:
907 memvalid |= (1 << filter[pc].k);
908 break;
909 case BPF_LD | BPF_MEM:
910 case BPF_LDX | BPF_MEM:
911 if (!(memvalid & (1 << filter[pc].k))) {
912 ret = -EINVAL;
913 goto error;
914 }
915 break;
916 case BPF_JMP | BPF_JA:
917 /* A jump must set masks on target */
918 masks[pc + 1 + filter[pc].k] &= memvalid;
919 memvalid = ~0;
920 break;
921 case BPF_JMP | BPF_JEQ | BPF_K:
922 case BPF_JMP | BPF_JEQ | BPF_X:
923 case BPF_JMP | BPF_JGE | BPF_K:
924 case BPF_JMP | BPF_JGE | BPF_X:
925 case BPF_JMP | BPF_JGT | BPF_K:
926 case BPF_JMP | BPF_JGT | BPF_X:
927 case BPF_JMP | BPF_JSET | BPF_K:
928 case BPF_JMP | BPF_JSET | BPF_X:
929 /* A jump must set masks on targets */
930 masks[pc + 1 + filter[pc].jt] &= memvalid;
931 masks[pc + 1 + filter[pc].jf] &= memvalid;
932 memvalid = ~0;
933 break;
934 }
935 }
936 error:
937 kfree(masks);
938 return ret;
939 }
940
chk_code_allowed(u16 code_to_probe)941 static bool chk_code_allowed(u16 code_to_probe)
942 {
943 static const bool codes[] = {
944 /* 32 bit ALU operations */
945 [BPF_ALU | BPF_ADD | BPF_K] = true,
946 [BPF_ALU | BPF_ADD | BPF_X] = true,
947 [BPF_ALU | BPF_SUB | BPF_K] = true,
948 [BPF_ALU | BPF_SUB | BPF_X] = true,
949 [BPF_ALU | BPF_MUL | BPF_K] = true,
950 [BPF_ALU | BPF_MUL | BPF_X] = true,
951 [BPF_ALU | BPF_DIV | BPF_K] = true,
952 [BPF_ALU | BPF_DIV | BPF_X] = true,
953 [BPF_ALU | BPF_MOD | BPF_K] = true,
954 [BPF_ALU | BPF_MOD | BPF_X] = true,
955 [BPF_ALU | BPF_AND | BPF_K] = true,
956 [BPF_ALU | BPF_AND | BPF_X] = true,
957 [BPF_ALU | BPF_OR | BPF_K] = true,
958 [BPF_ALU | BPF_OR | BPF_X] = true,
959 [BPF_ALU | BPF_XOR | BPF_K] = true,
960 [BPF_ALU | BPF_XOR | BPF_X] = true,
961 [BPF_ALU | BPF_LSH | BPF_K] = true,
962 [BPF_ALU | BPF_LSH | BPF_X] = true,
963 [BPF_ALU | BPF_RSH | BPF_K] = true,
964 [BPF_ALU | BPF_RSH | BPF_X] = true,
965 [BPF_ALU | BPF_NEG] = true,
966 /* Load instructions */
967 [BPF_LD | BPF_W | BPF_ABS] = true,
968 [BPF_LD | BPF_H | BPF_ABS] = true,
969 [BPF_LD | BPF_B | BPF_ABS] = true,
970 [BPF_LD | BPF_W | BPF_LEN] = true,
971 [BPF_LD | BPF_W | BPF_IND] = true,
972 [BPF_LD | BPF_H | BPF_IND] = true,
973 [BPF_LD | BPF_B | BPF_IND] = true,
974 [BPF_LD | BPF_IMM] = true,
975 [BPF_LD | BPF_MEM] = true,
976 [BPF_LDX | BPF_W | BPF_LEN] = true,
977 [BPF_LDX | BPF_B | BPF_MSH] = true,
978 [BPF_LDX | BPF_IMM] = true,
979 [BPF_LDX | BPF_MEM] = true,
980 /* Store instructions */
981 [BPF_ST] = true,
982 [BPF_STX] = true,
983 /* Misc instructions */
984 [BPF_MISC | BPF_TAX] = true,
985 [BPF_MISC | BPF_TXA] = true,
986 /* Return instructions */
987 [BPF_RET | BPF_K] = true,
988 [BPF_RET | BPF_A] = true,
989 /* Jump instructions */
990 [BPF_JMP | BPF_JA] = true,
991 [BPF_JMP | BPF_JEQ | BPF_K] = true,
992 [BPF_JMP | BPF_JEQ | BPF_X] = true,
993 [BPF_JMP | BPF_JGE | BPF_K] = true,
994 [BPF_JMP | BPF_JGE | BPF_X] = true,
995 [BPF_JMP | BPF_JGT | BPF_K] = true,
996 [BPF_JMP | BPF_JGT | BPF_X] = true,
997 [BPF_JMP | BPF_JSET | BPF_K] = true,
998 [BPF_JMP | BPF_JSET | BPF_X] = true,
999 };
1000
1001 if (code_to_probe >= ARRAY_SIZE(codes))
1002 return false;
1003
1004 return codes[code_to_probe];
1005 }
1006
bpf_check_basics_ok(const struct sock_filter * filter,unsigned int flen)1007 static bool bpf_check_basics_ok(const struct sock_filter *filter,
1008 unsigned int flen)
1009 {
1010 if (filter == NULL)
1011 return false;
1012 if (flen == 0 || flen > BPF_MAXINSNS)
1013 return false;
1014
1015 return true;
1016 }
1017
1018 /**
1019 * bpf_check_classic - verify socket filter code
1020 * @filter: filter to verify
1021 * @flen: length of filter
1022 *
1023 * Check the user's filter code. If we let some ugly
1024 * filter code slip through kaboom! The filter must contain
1025 * no references or jumps that are out of range, no illegal
1026 * instructions, and must end with a RET instruction.
1027 *
1028 * All jumps are forward as they are not signed.
1029 *
1030 * Returns 0 if the rule set is legal or -EINVAL if not.
1031 */
bpf_check_classic(const struct sock_filter * filter,unsigned int flen)1032 static int bpf_check_classic(const struct sock_filter *filter,
1033 unsigned int flen)
1034 {
1035 bool anc_found;
1036 int pc;
1037
1038 /* Check the filter code now */
1039 for (pc = 0; pc < flen; pc++) {
1040 const struct sock_filter *ftest = &filter[pc];
1041
1042 /* May we actually operate on this code? */
1043 if (!chk_code_allowed(ftest->code))
1044 return -EINVAL;
1045
1046 /* Some instructions need special checks */
1047 switch (ftest->code) {
1048 case BPF_ALU | BPF_DIV | BPF_K:
1049 case BPF_ALU | BPF_MOD | BPF_K:
1050 /* Check for division by zero */
1051 if (ftest->k == 0)
1052 return -EINVAL;
1053 break;
1054 case BPF_ALU | BPF_LSH | BPF_K:
1055 case BPF_ALU | BPF_RSH | BPF_K:
1056 if (ftest->k >= 32)
1057 return -EINVAL;
1058 break;
1059 case BPF_LD | BPF_MEM:
1060 case BPF_LDX | BPF_MEM:
1061 case BPF_ST:
1062 case BPF_STX:
1063 /* Check for invalid memory addresses */
1064 if (ftest->k >= BPF_MEMWORDS)
1065 return -EINVAL;
1066 break;
1067 case BPF_JMP | BPF_JA:
1068 /* Note, the large ftest->k might cause loops.
1069 * Compare this with conditional jumps below,
1070 * where offsets are limited. --ANK (981016)
1071 */
1072 if (ftest->k >= (unsigned int)(flen - pc - 1))
1073 return -EINVAL;
1074 break;
1075 case BPF_JMP | BPF_JEQ | BPF_K:
1076 case BPF_JMP | BPF_JEQ | BPF_X:
1077 case BPF_JMP | BPF_JGE | BPF_K:
1078 case BPF_JMP | BPF_JGE | BPF_X:
1079 case BPF_JMP | BPF_JGT | BPF_K:
1080 case BPF_JMP | BPF_JGT | BPF_X:
1081 case BPF_JMP | BPF_JSET | BPF_K:
1082 case BPF_JMP | BPF_JSET | BPF_X:
1083 /* Both conditionals must be safe */
1084 if (pc + ftest->jt + 1 >= flen ||
1085 pc + ftest->jf + 1 >= flen)
1086 return -EINVAL;
1087 break;
1088 case BPF_LD | BPF_W | BPF_ABS:
1089 case BPF_LD | BPF_H | BPF_ABS:
1090 case BPF_LD | BPF_B | BPF_ABS:
1091 anc_found = false;
1092 if (bpf_anc_helper(ftest) & BPF_ANC)
1093 anc_found = true;
1094 /* Ancillary operation unknown or unsupported */
1095 if (anc_found == false && ftest->k >= SKF_AD_OFF)
1096 return -EINVAL;
1097 }
1098 }
1099
1100 /* Last instruction must be a RET code */
1101 switch (filter[flen - 1].code) {
1102 case BPF_RET | BPF_K:
1103 case BPF_RET | BPF_A:
1104 return check_load_and_stores(filter, flen);
1105 }
1106
1107 return -EINVAL;
1108 }
1109
bpf_prog_store_orig_filter(struct bpf_prog * fp,const struct sock_fprog * fprog)1110 static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
1111 const struct sock_fprog *fprog)
1112 {
1113 unsigned int fsize = bpf_classic_proglen(fprog);
1114 struct sock_fprog_kern *fkprog;
1115
1116 fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
1117 if (!fp->orig_prog)
1118 return -ENOMEM;
1119
1120 fkprog = fp->orig_prog;
1121 fkprog->len = fprog->len;
1122
1123 fkprog->filter = kmemdup(fp->insns, fsize,
1124 GFP_KERNEL | __GFP_NOWARN);
1125 if (!fkprog->filter) {
1126 kfree(fp->orig_prog);
1127 return -ENOMEM;
1128 }
1129
1130 return 0;
1131 }
1132
bpf_release_orig_filter(struct bpf_prog * fp)1133 static void bpf_release_orig_filter(struct bpf_prog *fp)
1134 {
1135 struct sock_fprog_kern *fprog = fp->orig_prog;
1136
1137 if (fprog) {
1138 kfree(fprog->filter);
1139 kfree(fprog);
1140 }
1141 }
1142
__bpf_prog_release(struct bpf_prog * prog)1143 static void __bpf_prog_release(struct bpf_prog *prog)
1144 {
1145 if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
1146 bpf_prog_put(prog);
1147 } else {
1148 bpf_release_orig_filter(prog);
1149 bpf_prog_free(prog);
1150 }
1151 }
1152
__sk_filter_release(struct sk_filter * fp)1153 static void __sk_filter_release(struct sk_filter *fp)
1154 {
1155 __bpf_prog_release(fp->prog);
1156 kfree(fp);
1157 }
1158
1159 /**
1160 * sk_filter_release_rcu - Release a socket filter by rcu_head
1161 * @rcu: rcu_head that contains the sk_filter to free
1162 */
sk_filter_release_rcu(struct rcu_head * rcu)1163 static void sk_filter_release_rcu(struct rcu_head *rcu)
1164 {
1165 struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
1166
1167 __sk_filter_release(fp);
1168 }
1169
1170 /**
1171 * sk_filter_release - release a socket filter
1172 * @fp: filter to remove
1173 *
1174 * Remove a filter from a socket and release its resources.
1175 */
sk_filter_release(struct sk_filter * fp)1176 static void sk_filter_release(struct sk_filter *fp)
1177 {
1178 if (refcount_dec_and_test(&fp->refcnt))
1179 call_rcu(&fp->rcu, sk_filter_release_rcu);
1180 }
1181
sk_filter_uncharge(struct sock * sk,struct sk_filter * fp)1182 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1183 {
1184 u32 filter_size = bpf_prog_size(fp->prog->len);
1185
1186 atomic_sub(filter_size, &sk->sk_omem_alloc);
1187 sk_filter_release(fp);
1188 }
1189
1190 /* try to charge the socket memory if there is space available
1191 * return true on success
1192 */
__sk_filter_charge(struct sock * sk,struct sk_filter * fp)1193 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1194 {
1195 u32 filter_size = bpf_prog_size(fp->prog->len);
1196
1197 /* same check as in sock_kmalloc() */
1198 if (filter_size <= sysctl_optmem_max &&
1199 atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) {
1200 atomic_add(filter_size, &sk->sk_omem_alloc);
1201 return true;
1202 }
1203 return false;
1204 }
1205
sk_filter_charge(struct sock * sk,struct sk_filter * fp)1206 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1207 {
1208 if (!refcount_inc_not_zero(&fp->refcnt))
1209 return false;
1210
1211 if (!__sk_filter_charge(sk, fp)) {
1212 sk_filter_release(fp);
1213 return false;
1214 }
1215 return true;
1216 }
1217
bpf_migrate_filter(struct bpf_prog * fp)1218 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
1219 {
1220 struct sock_filter *old_prog;
1221 struct bpf_prog *old_fp;
1222 int err, new_len, old_len = fp->len;
1223 bool seen_ld_abs = false;
1224
1225 /* We are free to overwrite insns et al right here as it
1226 * won't be used at this point in time anymore internally
1227 * after the migration to the internal BPF instruction
1228 * representation.
1229 */
1230 BUILD_BUG_ON(sizeof(struct sock_filter) !=
1231 sizeof(struct bpf_insn));
1232
1233 /* Conversion cannot happen on overlapping memory areas,
1234 * so we need to keep the user BPF around until the 2nd
1235 * pass. At this time, the user BPF is stored in fp->insns.
1236 */
1237 old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
1238 GFP_KERNEL | __GFP_NOWARN);
1239 if (!old_prog) {
1240 err = -ENOMEM;
1241 goto out_err;
1242 }
1243
1244 /* 1st pass: calculate the new program length. */
1245 err = bpf_convert_filter(old_prog, old_len, NULL, &new_len,
1246 &seen_ld_abs);
1247 if (err)
1248 goto out_err_free;
1249
1250 /* Expand fp for appending the new filter representation. */
1251 old_fp = fp;
1252 fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
1253 if (!fp) {
1254 /* The old_fp is still around in case we couldn't
1255 * allocate new memory, so uncharge on that one.
1256 */
1257 fp = old_fp;
1258 err = -ENOMEM;
1259 goto out_err_free;
1260 }
1261
1262 fp->len = new_len;
1263
1264 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
1265 err = bpf_convert_filter(old_prog, old_len, fp, &new_len,
1266 &seen_ld_abs);
1267 if (err)
1268 /* 2nd bpf_convert_filter() can fail only if it fails
1269 * to allocate memory, remapping must succeed. Note,
1270 * that at this time old_fp has already been released
1271 * by krealloc().
1272 */
1273 goto out_err_free;
1274
1275 fp = bpf_prog_select_runtime(fp, &err);
1276 if (err)
1277 goto out_err_free;
1278
1279 kfree(old_prog);
1280 return fp;
1281
1282 out_err_free:
1283 kfree(old_prog);
1284 out_err:
1285 __bpf_prog_release(fp);
1286 return ERR_PTR(err);
1287 }
1288
bpf_prepare_filter(struct bpf_prog * fp,bpf_aux_classic_check_t trans)1289 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
1290 bpf_aux_classic_check_t trans)
1291 {
1292 int err;
1293
1294 fp->bpf_func = NULL;
1295 fp->jited = 0;
1296
1297 err = bpf_check_classic(fp->insns, fp->len);
1298 if (err) {
1299 __bpf_prog_release(fp);
1300 return ERR_PTR(err);
1301 }
1302
1303 /* There might be additional checks and transformations
1304 * needed on classic filters, f.e. in case of seccomp.
1305 */
1306 if (trans) {
1307 err = trans(fp->insns, fp->len);
1308 if (err) {
1309 __bpf_prog_release(fp);
1310 return ERR_PTR(err);
1311 }
1312 }
1313
1314 /* Probe if we can JIT compile the filter and if so, do
1315 * the compilation of the filter.
1316 */
1317 bpf_jit_compile(fp);
1318
1319 /* JIT compiler couldn't process this filter, so do the
1320 * internal BPF translation for the optimized interpreter.
1321 */
1322 if (!fp->jited)
1323 fp = bpf_migrate_filter(fp);
1324
1325 return fp;
1326 }
1327
1328 /**
1329 * bpf_prog_create - create an unattached filter
1330 * @pfp: the unattached filter that is created
1331 * @fprog: the filter program
1332 *
1333 * Create a filter independent of any socket. We first run some
1334 * sanity checks on it to make sure it does not explode on us later.
1335 * If an error occurs or there is insufficient memory for the filter
1336 * a negative errno code is returned. On success the return is zero.
1337 */
bpf_prog_create(struct bpf_prog ** pfp,struct sock_fprog_kern * fprog)1338 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
1339 {
1340 unsigned int fsize = bpf_classic_proglen(fprog);
1341 struct bpf_prog *fp;
1342
1343 /* Make sure new filter is there and in the right amounts. */
1344 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1345 return -EINVAL;
1346
1347 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1348 if (!fp)
1349 return -ENOMEM;
1350
1351 memcpy(fp->insns, fprog->filter, fsize);
1352
1353 fp->len = fprog->len;
1354 /* Since unattached filters are not copied back to user
1355 * space through sk_get_filter(), we do not need to hold
1356 * a copy here, and can spare us the work.
1357 */
1358 fp->orig_prog = NULL;
1359
1360 /* bpf_prepare_filter() already takes care of freeing
1361 * memory in case something goes wrong.
1362 */
1363 fp = bpf_prepare_filter(fp, NULL);
1364 if (IS_ERR(fp))
1365 return PTR_ERR(fp);
1366
1367 *pfp = fp;
1368 return 0;
1369 }
1370 EXPORT_SYMBOL_GPL(bpf_prog_create);
1371
1372 /**
1373 * bpf_prog_create_from_user - create an unattached filter from user buffer
1374 * @pfp: the unattached filter that is created
1375 * @fprog: the filter program
1376 * @trans: post-classic verifier transformation handler
1377 * @save_orig: save classic BPF program
1378 *
1379 * This function effectively does the same as bpf_prog_create(), only
1380 * that it builds up its insns buffer from user space provided buffer.
1381 * It also allows for passing a bpf_aux_classic_check_t handler.
1382 */
bpf_prog_create_from_user(struct bpf_prog ** pfp,struct sock_fprog * fprog,bpf_aux_classic_check_t trans,bool save_orig)1383 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
1384 bpf_aux_classic_check_t trans, bool save_orig)
1385 {
1386 unsigned int fsize = bpf_classic_proglen(fprog);
1387 struct bpf_prog *fp;
1388 int err;
1389
1390 /* Make sure new filter is there and in the right amounts. */
1391 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1392 return -EINVAL;
1393
1394 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1395 if (!fp)
1396 return -ENOMEM;
1397
1398 if (copy_from_user(fp->insns, fprog->filter, fsize)) {
1399 __bpf_prog_free(fp);
1400 return -EFAULT;
1401 }
1402
1403 fp->len = fprog->len;
1404 fp->orig_prog = NULL;
1405
1406 if (save_orig) {
1407 err = bpf_prog_store_orig_filter(fp, fprog);
1408 if (err) {
1409 __bpf_prog_free(fp);
1410 return -ENOMEM;
1411 }
1412 }
1413
1414 /* bpf_prepare_filter() already takes care of freeing
1415 * memory in case something goes wrong.
1416 */
1417 fp = bpf_prepare_filter(fp, trans);
1418 if (IS_ERR(fp))
1419 return PTR_ERR(fp);
1420
1421 *pfp = fp;
1422 return 0;
1423 }
1424 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
1425
bpf_prog_destroy(struct bpf_prog * fp)1426 void bpf_prog_destroy(struct bpf_prog *fp)
1427 {
1428 __bpf_prog_release(fp);
1429 }
1430 EXPORT_SYMBOL_GPL(bpf_prog_destroy);
1431
__sk_attach_prog(struct bpf_prog * prog,struct sock * sk)1432 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
1433 {
1434 struct sk_filter *fp, *old_fp;
1435
1436 fp = kmalloc(sizeof(*fp), GFP_KERNEL);
1437 if (!fp)
1438 return -ENOMEM;
1439
1440 fp->prog = prog;
1441
1442 if (!__sk_filter_charge(sk, fp)) {
1443 kfree(fp);
1444 return -ENOMEM;
1445 }
1446 refcount_set(&fp->refcnt, 1);
1447
1448 old_fp = rcu_dereference_protected(sk->sk_filter,
1449 lockdep_sock_is_held(sk));
1450 rcu_assign_pointer(sk->sk_filter, fp);
1451
1452 if (old_fp)
1453 sk_filter_uncharge(sk, old_fp);
1454
1455 return 0;
1456 }
1457
1458 static
__get_filter(struct sock_fprog * fprog,struct sock * sk)1459 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
1460 {
1461 unsigned int fsize = bpf_classic_proglen(fprog);
1462 struct bpf_prog *prog;
1463 int err;
1464
1465 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1466 return ERR_PTR(-EPERM);
1467
1468 /* Make sure new filter is there and in the right amounts. */
1469 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1470 return ERR_PTR(-EINVAL);
1471
1472 prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1473 if (!prog)
1474 return ERR_PTR(-ENOMEM);
1475
1476 if (copy_from_user(prog->insns, fprog->filter, fsize)) {
1477 __bpf_prog_free(prog);
1478 return ERR_PTR(-EINVAL);
1479 }
1480
1481 prog->len = fprog->len;
1482
1483 err = bpf_prog_store_orig_filter(prog, fprog);
1484 if (err) {
1485 __bpf_prog_free(prog);
1486 return ERR_PTR(-ENOMEM);
1487 }
1488
1489 /* bpf_prepare_filter() already takes care of freeing
1490 * memory in case something goes wrong.
1491 */
1492 return bpf_prepare_filter(prog, NULL);
1493 }
1494
1495 /**
1496 * sk_attach_filter - attach a socket filter
1497 * @fprog: the filter program
1498 * @sk: the socket to use
1499 *
1500 * Attach the user's filter code. We first run some sanity checks on
1501 * it to make sure it does not explode on us later. If an error
1502 * occurs or there is insufficient memory for the filter a negative
1503 * errno code is returned. On success the return is zero.
1504 */
sk_attach_filter(struct sock_fprog * fprog,struct sock * sk)1505 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1506 {
1507 struct bpf_prog *prog = __get_filter(fprog, sk);
1508 int err;
1509
1510 if (IS_ERR(prog))
1511 return PTR_ERR(prog);
1512
1513 err = __sk_attach_prog(prog, sk);
1514 if (err < 0) {
1515 __bpf_prog_release(prog);
1516 return err;
1517 }
1518
1519 return 0;
1520 }
1521 EXPORT_SYMBOL_GPL(sk_attach_filter);
1522
sk_reuseport_attach_filter(struct sock_fprog * fprog,struct sock * sk)1523 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1524 {
1525 struct bpf_prog *prog = __get_filter(fprog, sk);
1526 int err;
1527
1528 if (IS_ERR(prog))
1529 return PTR_ERR(prog);
1530
1531 if (bpf_prog_size(prog->len) > sysctl_optmem_max)
1532 err = -ENOMEM;
1533 else
1534 err = reuseport_attach_prog(sk, prog);
1535
1536 if (err)
1537 __bpf_prog_release(prog);
1538
1539 return err;
1540 }
1541
__get_bpf(u32 ufd,struct sock * sk)1542 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
1543 {
1544 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1545 return ERR_PTR(-EPERM);
1546
1547 return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1548 }
1549
sk_attach_bpf(u32 ufd,struct sock * sk)1550 int sk_attach_bpf(u32 ufd, struct sock *sk)
1551 {
1552 struct bpf_prog *prog = __get_bpf(ufd, sk);
1553 int err;
1554
1555 if (IS_ERR(prog))
1556 return PTR_ERR(prog);
1557
1558 err = __sk_attach_prog(prog, sk);
1559 if (err < 0) {
1560 bpf_prog_put(prog);
1561 return err;
1562 }
1563
1564 return 0;
1565 }
1566
sk_reuseport_attach_bpf(u32 ufd,struct sock * sk)1567 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
1568 {
1569 struct bpf_prog *prog;
1570 int err;
1571
1572 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1573 return -EPERM;
1574
1575 prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1576 if (IS_ERR(prog) && PTR_ERR(prog) == -EINVAL)
1577 prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SK_REUSEPORT);
1578 if (IS_ERR(prog))
1579 return PTR_ERR(prog);
1580
1581 if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT) {
1582 /* Like other non BPF_PROG_TYPE_SOCKET_FILTER
1583 * bpf prog (e.g. sockmap). It depends on the
1584 * limitation imposed by bpf_prog_load().
1585 * Hence, sysctl_optmem_max is not checked.
1586 */
1587 if ((sk->sk_type != SOCK_STREAM &&
1588 sk->sk_type != SOCK_DGRAM) ||
1589 (sk->sk_protocol != IPPROTO_UDP &&
1590 sk->sk_protocol != IPPROTO_TCP) ||
1591 (sk->sk_family != AF_INET &&
1592 sk->sk_family != AF_INET6)) {
1593 err = -ENOTSUPP;
1594 goto err_prog_put;
1595 }
1596 } else {
1597 /* BPF_PROG_TYPE_SOCKET_FILTER */
1598 if (bpf_prog_size(prog->len) > sysctl_optmem_max) {
1599 err = -ENOMEM;
1600 goto err_prog_put;
1601 }
1602 }
1603
1604 err = reuseport_attach_prog(sk, prog);
1605 err_prog_put:
1606 if (err)
1607 bpf_prog_put(prog);
1608
1609 return err;
1610 }
1611
sk_reuseport_prog_free(struct bpf_prog * prog)1612 void sk_reuseport_prog_free(struct bpf_prog *prog)
1613 {
1614 if (!prog)
1615 return;
1616
1617 if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT)
1618 bpf_prog_put(prog);
1619 else
1620 bpf_prog_destroy(prog);
1621 }
1622
1623 struct bpf_scratchpad {
1624 union {
1625 __be32 diff[MAX_BPF_STACK / sizeof(__be32)];
1626 u8 buff[MAX_BPF_STACK];
1627 };
1628 };
1629
1630 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
1631
__bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1632 static inline int __bpf_try_make_writable(struct sk_buff *skb,
1633 unsigned int write_len)
1634 {
1635 return skb_ensure_writable(skb, write_len);
1636 }
1637
bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1638 static inline int bpf_try_make_writable(struct sk_buff *skb,
1639 unsigned int write_len)
1640 {
1641 int err = __bpf_try_make_writable(skb, write_len);
1642
1643 bpf_compute_data_pointers(skb);
1644 return err;
1645 }
1646
bpf_try_make_head_writable(struct sk_buff * skb)1647 static int bpf_try_make_head_writable(struct sk_buff *skb)
1648 {
1649 return bpf_try_make_writable(skb, skb_headlen(skb));
1650 }
1651
bpf_push_mac_rcsum(struct sk_buff * skb)1652 static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
1653 {
1654 if (skb_at_tc_ingress(skb))
1655 skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1656 }
1657
bpf_pull_mac_rcsum(struct sk_buff * skb)1658 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
1659 {
1660 if (skb_at_tc_ingress(skb))
1661 skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1662 }
1663
BPF_CALL_5(bpf_skb_store_bytes,struct sk_buff *,skb,u32,offset,const void *,from,u32,len,u64,flags)1664 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
1665 const void *, from, u32, len, u64, flags)
1666 {
1667 void *ptr;
1668
1669 if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
1670 return -EINVAL;
1671 if (unlikely(offset > INT_MAX))
1672 return -EFAULT;
1673 if (unlikely(bpf_try_make_writable(skb, offset + len)))
1674 return -EFAULT;
1675
1676 ptr = skb->data + offset;
1677 if (flags & BPF_F_RECOMPUTE_CSUM)
1678 __skb_postpull_rcsum(skb, ptr, len, offset);
1679
1680 memcpy(ptr, from, len);
1681
1682 if (flags & BPF_F_RECOMPUTE_CSUM)
1683 __skb_postpush_rcsum(skb, ptr, len, offset);
1684 if (flags & BPF_F_INVALIDATE_HASH)
1685 skb_clear_hash(skb);
1686
1687 return 0;
1688 }
1689
1690 static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
1691 .func = bpf_skb_store_bytes,
1692 .gpl_only = false,
1693 .ret_type = RET_INTEGER,
1694 .arg1_type = ARG_PTR_TO_CTX,
1695 .arg2_type = ARG_ANYTHING,
1696 .arg3_type = ARG_PTR_TO_MEM,
1697 .arg4_type = ARG_CONST_SIZE,
1698 .arg5_type = ARG_ANYTHING,
1699 };
1700
BPF_CALL_4(bpf_skb_load_bytes,const struct sk_buff *,skb,u32,offset,void *,to,u32,len)1701 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
1702 void *, to, u32, len)
1703 {
1704 void *ptr;
1705
1706 if (unlikely(offset > INT_MAX))
1707 goto err_clear;
1708
1709 ptr = skb_header_pointer(skb, offset, len, to);
1710 if (unlikely(!ptr))
1711 goto err_clear;
1712 if (ptr != to)
1713 memcpy(to, ptr, len);
1714
1715 return 0;
1716 err_clear:
1717 memset(to, 0, len);
1718 return -EFAULT;
1719 }
1720
1721 static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
1722 .func = bpf_skb_load_bytes,
1723 .gpl_only = false,
1724 .ret_type = RET_INTEGER,
1725 .arg1_type = ARG_PTR_TO_CTX,
1726 .arg2_type = ARG_ANYTHING,
1727 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
1728 .arg4_type = ARG_CONST_SIZE,
1729 };
1730
BPF_CALL_4(bpf_flow_dissector_load_bytes,const struct bpf_flow_dissector *,ctx,u32,offset,void *,to,u32,len)1731 BPF_CALL_4(bpf_flow_dissector_load_bytes,
1732 const struct bpf_flow_dissector *, ctx, u32, offset,
1733 void *, to, u32, len)
1734 {
1735 void *ptr;
1736
1737 if (unlikely(offset > 0xffff))
1738 goto err_clear;
1739
1740 if (unlikely(!ctx->skb))
1741 goto err_clear;
1742
1743 ptr = skb_header_pointer(ctx->skb, offset, len, to);
1744 if (unlikely(!ptr))
1745 goto err_clear;
1746 if (ptr != to)
1747 memcpy(to, ptr, len);
1748
1749 return 0;
1750 err_clear:
1751 memset(to, 0, len);
1752 return -EFAULT;
1753 }
1754
1755 static const struct bpf_func_proto bpf_flow_dissector_load_bytes_proto = {
1756 .func = bpf_flow_dissector_load_bytes,
1757 .gpl_only = false,
1758 .ret_type = RET_INTEGER,
1759 .arg1_type = ARG_PTR_TO_CTX,
1760 .arg2_type = ARG_ANYTHING,
1761 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
1762 .arg4_type = ARG_CONST_SIZE,
1763 };
1764
BPF_CALL_5(bpf_skb_load_bytes_relative,const struct sk_buff *,skb,u32,offset,void *,to,u32,len,u32,start_header)1765 BPF_CALL_5(bpf_skb_load_bytes_relative, const struct sk_buff *, skb,
1766 u32, offset, void *, to, u32, len, u32, start_header)
1767 {
1768 u8 *end = skb_tail_pointer(skb);
1769 u8 *start, *ptr;
1770
1771 if (unlikely(offset > 0xffff))
1772 goto err_clear;
1773
1774 switch (start_header) {
1775 case BPF_HDR_START_MAC:
1776 if (unlikely(!skb_mac_header_was_set(skb)))
1777 goto err_clear;
1778 start = skb_mac_header(skb);
1779 break;
1780 case BPF_HDR_START_NET:
1781 start = skb_network_header(skb);
1782 break;
1783 default:
1784 goto err_clear;
1785 }
1786
1787 ptr = start + offset;
1788
1789 if (likely(ptr + len <= end)) {
1790 memcpy(to, ptr, len);
1791 return 0;
1792 }
1793
1794 err_clear:
1795 memset(to, 0, len);
1796 return -EFAULT;
1797 }
1798
1799 static const struct bpf_func_proto bpf_skb_load_bytes_relative_proto = {
1800 .func = bpf_skb_load_bytes_relative,
1801 .gpl_only = false,
1802 .ret_type = RET_INTEGER,
1803 .arg1_type = ARG_PTR_TO_CTX,
1804 .arg2_type = ARG_ANYTHING,
1805 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
1806 .arg4_type = ARG_CONST_SIZE,
1807 .arg5_type = ARG_ANYTHING,
1808 };
1809
BPF_CALL_2(bpf_skb_pull_data,struct sk_buff *,skb,u32,len)1810 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
1811 {
1812 /* Idea is the following: should the needed direct read/write
1813 * test fail during runtime, we can pull in more data and redo
1814 * again, since implicitly, we invalidate previous checks here.
1815 *
1816 * Or, since we know how much we need to make read/writeable,
1817 * this can be done once at the program beginning for direct
1818 * access case. By this we overcome limitations of only current
1819 * headroom being accessible.
1820 */
1821 return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
1822 }
1823
1824 static const struct bpf_func_proto bpf_skb_pull_data_proto = {
1825 .func = bpf_skb_pull_data,
1826 .gpl_only = false,
1827 .ret_type = RET_INTEGER,
1828 .arg1_type = ARG_PTR_TO_CTX,
1829 .arg2_type = ARG_ANYTHING,
1830 };
1831
BPF_CALL_1(bpf_sk_fullsock,struct sock *,sk)1832 BPF_CALL_1(bpf_sk_fullsock, struct sock *, sk)
1833 {
1834 return sk_fullsock(sk) ? (unsigned long)sk : (unsigned long)NULL;
1835 }
1836
1837 static const struct bpf_func_proto bpf_sk_fullsock_proto = {
1838 .func = bpf_sk_fullsock,
1839 .gpl_only = false,
1840 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
1841 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
1842 };
1843
sk_skb_try_make_writable(struct sk_buff * skb,unsigned int write_len)1844 static inline int sk_skb_try_make_writable(struct sk_buff *skb,
1845 unsigned int write_len)
1846 {
1847 int err = __bpf_try_make_writable(skb, write_len);
1848
1849 bpf_compute_data_end_sk_skb(skb);
1850 return err;
1851 }
1852
BPF_CALL_2(sk_skb_pull_data,struct sk_buff *,skb,u32,len)1853 BPF_CALL_2(sk_skb_pull_data, struct sk_buff *, skb, u32, len)
1854 {
1855 /* Idea is the following: should the needed direct read/write
1856 * test fail during runtime, we can pull in more data and redo
1857 * again, since implicitly, we invalidate previous checks here.
1858 *
1859 * Or, since we know how much we need to make read/writeable,
1860 * this can be done once at the program beginning for direct
1861 * access case. By this we overcome limitations of only current
1862 * headroom being accessible.
1863 */
1864 return sk_skb_try_make_writable(skb, len ? : skb_headlen(skb));
1865 }
1866
1867 static const struct bpf_func_proto sk_skb_pull_data_proto = {
1868 .func = sk_skb_pull_data,
1869 .gpl_only = false,
1870 .ret_type = RET_INTEGER,
1871 .arg1_type = ARG_PTR_TO_CTX,
1872 .arg2_type = ARG_ANYTHING,
1873 };
1874
BPF_CALL_5(bpf_l3_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1875 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
1876 u64, from, u64, to, u64, flags)
1877 {
1878 __sum16 *ptr;
1879
1880 if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
1881 return -EINVAL;
1882 if (unlikely(offset > 0xffff || offset & 1))
1883 return -EFAULT;
1884 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1885 return -EFAULT;
1886
1887 ptr = (__sum16 *)(skb->data + offset);
1888 switch (flags & BPF_F_HDR_FIELD_MASK) {
1889 case 0:
1890 if (unlikely(from != 0))
1891 return -EINVAL;
1892
1893 csum_replace_by_diff(ptr, to);
1894 break;
1895 case 2:
1896 csum_replace2(ptr, from, to);
1897 break;
1898 case 4:
1899 csum_replace4(ptr, from, to);
1900 break;
1901 default:
1902 return -EINVAL;
1903 }
1904
1905 return 0;
1906 }
1907
1908 static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
1909 .func = bpf_l3_csum_replace,
1910 .gpl_only = false,
1911 .ret_type = RET_INTEGER,
1912 .arg1_type = ARG_PTR_TO_CTX,
1913 .arg2_type = ARG_ANYTHING,
1914 .arg3_type = ARG_ANYTHING,
1915 .arg4_type = ARG_ANYTHING,
1916 .arg5_type = ARG_ANYTHING,
1917 };
1918
BPF_CALL_5(bpf_l4_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1919 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
1920 u64, from, u64, to, u64, flags)
1921 {
1922 bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
1923 bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
1924 bool do_mforce = flags & BPF_F_MARK_ENFORCE;
1925 __sum16 *ptr;
1926
1927 if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
1928 BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
1929 return -EINVAL;
1930 if (unlikely(offset > 0xffff || offset & 1))
1931 return -EFAULT;
1932 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1933 return -EFAULT;
1934
1935 ptr = (__sum16 *)(skb->data + offset);
1936 if (is_mmzero && !do_mforce && !*ptr)
1937 return 0;
1938
1939 switch (flags & BPF_F_HDR_FIELD_MASK) {
1940 case 0:
1941 if (unlikely(from != 0))
1942 return -EINVAL;
1943
1944 inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
1945 break;
1946 case 2:
1947 inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
1948 break;
1949 case 4:
1950 inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
1951 break;
1952 default:
1953 return -EINVAL;
1954 }
1955
1956 if (is_mmzero && !*ptr)
1957 *ptr = CSUM_MANGLED_0;
1958 return 0;
1959 }
1960
1961 static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
1962 .func = bpf_l4_csum_replace,
1963 .gpl_only = false,
1964 .ret_type = RET_INTEGER,
1965 .arg1_type = ARG_PTR_TO_CTX,
1966 .arg2_type = ARG_ANYTHING,
1967 .arg3_type = ARG_ANYTHING,
1968 .arg4_type = ARG_ANYTHING,
1969 .arg5_type = ARG_ANYTHING,
1970 };
1971
BPF_CALL_5(bpf_csum_diff,__be32 *,from,u32,from_size,__be32 *,to,u32,to_size,__wsum,seed)1972 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
1973 __be32 *, to, u32, to_size, __wsum, seed)
1974 {
1975 struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
1976 u32 diff_size = from_size + to_size;
1977 int i, j = 0;
1978
1979 /* This is quite flexible, some examples:
1980 *
1981 * from_size == 0, to_size > 0, seed := csum --> pushing data
1982 * from_size > 0, to_size == 0, seed := csum --> pulling data
1983 * from_size > 0, to_size > 0, seed := 0 --> diffing data
1984 *
1985 * Even for diffing, from_size and to_size don't need to be equal.
1986 */
1987 if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
1988 diff_size > sizeof(sp->diff)))
1989 return -EINVAL;
1990
1991 for (i = 0; i < from_size / sizeof(__be32); i++, j++)
1992 sp->diff[j] = ~from[i];
1993 for (i = 0; i < to_size / sizeof(__be32); i++, j++)
1994 sp->diff[j] = to[i];
1995
1996 return csum_partial(sp->diff, diff_size, seed);
1997 }
1998
1999 static const struct bpf_func_proto bpf_csum_diff_proto = {
2000 .func = bpf_csum_diff,
2001 .gpl_only = false,
2002 .pkt_access = true,
2003 .ret_type = RET_INTEGER,
2004 .arg1_type = ARG_PTR_TO_MEM_OR_NULL,
2005 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
2006 .arg3_type = ARG_PTR_TO_MEM_OR_NULL,
2007 .arg4_type = ARG_CONST_SIZE_OR_ZERO,
2008 .arg5_type = ARG_ANYTHING,
2009 };
2010
BPF_CALL_2(bpf_csum_update,struct sk_buff *,skb,__wsum,csum)2011 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
2012 {
2013 /* The interface is to be used in combination with bpf_csum_diff()
2014 * for direct packet writes. csum rotation for alignment as well
2015 * as emulating csum_sub() can be done from the eBPF program.
2016 */
2017 if (skb->ip_summed == CHECKSUM_COMPLETE)
2018 return (skb->csum = csum_add(skb->csum, csum));
2019
2020 return -ENOTSUPP;
2021 }
2022
2023 static const struct bpf_func_proto bpf_csum_update_proto = {
2024 .func = bpf_csum_update,
2025 .gpl_only = false,
2026 .ret_type = RET_INTEGER,
2027 .arg1_type = ARG_PTR_TO_CTX,
2028 .arg2_type = ARG_ANYTHING,
2029 };
2030
__bpf_rx_skb(struct net_device * dev,struct sk_buff * skb)2031 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
2032 {
2033 return dev_forward_skb(dev, skb);
2034 }
2035
__bpf_rx_skb_no_mac(struct net_device * dev,struct sk_buff * skb)2036 static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
2037 struct sk_buff *skb)
2038 {
2039 int ret = ____dev_forward_skb(dev, skb);
2040
2041 if (likely(!ret)) {
2042 skb->dev = dev;
2043 ret = netif_rx(skb);
2044 }
2045
2046 return ret;
2047 }
2048
__bpf_tx_skb(struct net_device * dev,struct sk_buff * skb)2049 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
2050 {
2051 int ret;
2052
2053 if (dev_xmit_recursion()) {
2054 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2055 kfree_skb(skb);
2056 return -ENETDOWN;
2057 }
2058
2059 skb->dev = dev;
2060 skb->tstamp = 0;
2061
2062 dev_xmit_recursion_inc();
2063 ret = dev_queue_xmit(skb);
2064 dev_xmit_recursion_dec();
2065
2066 return ret;
2067 }
2068
__bpf_redirect_no_mac(struct sk_buff * skb,struct net_device * dev,u32 flags)2069 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
2070 u32 flags)
2071 {
2072 unsigned int mlen = skb_network_offset(skb);
2073
2074 if (unlikely(skb->len <= mlen)) {
2075 kfree_skb(skb);
2076 return -ERANGE;
2077 }
2078
2079 if (mlen) {
2080 __skb_pull(skb, mlen);
2081 if (unlikely(!skb->len)) {
2082 kfree_skb(skb);
2083 return -ERANGE;
2084 }
2085
2086 /* At ingress, the mac header has already been pulled once.
2087 * At egress, skb_pospull_rcsum has to be done in case that
2088 * the skb is originated from ingress (i.e. a forwarded skb)
2089 * to ensure that rcsum starts at net header.
2090 */
2091 if (!skb_at_tc_ingress(skb))
2092 skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
2093 }
2094 skb_pop_mac_header(skb);
2095 skb_reset_mac_len(skb);
2096 return flags & BPF_F_INGRESS ?
2097 __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
2098 }
2099
__bpf_redirect_common(struct sk_buff * skb,struct net_device * dev,u32 flags)2100 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
2101 u32 flags)
2102 {
2103 /* Verify that a link layer header is carried */
2104 if (unlikely(skb->mac_header >= skb->network_header || skb->len == 0)) {
2105 kfree_skb(skb);
2106 return -ERANGE;
2107 }
2108
2109 bpf_push_mac_rcsum(skb);
2110 return flags & BPF_F_INGRESS ?
2111 __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
2112 }
2113
__bpf_redirect(struct sk_buff * skb,struct net_device * dev,u32 flags)2114 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
2115 u32 flags)
2116 {
2117 if (dev_is_mac_header_xmit(dev))
2118 return __bpf_redirect_common(skb, dev, flags);
2119 else
2120 return __bpf_redirect_no_mac(skb, dev, flags);
2121 }
2122
BPF_CALL_3(bpf_clone_redirect,struct sk_buff *,skb,u32,ifindex,u64,flags)2123 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
2124 {
2125 struct net_device *dev;
2126 struct sk_buff *clone;
2127 int ret;
2128
2129 if (unlikely(flags & ~(BPF_F_INGRESS)))
2130 return -EINVAL;
2131
2132 dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
2133 if (unlikely(!dev))
2134 return -EINVAL;
2135
2136 clone = skb_clone(skb, GFP_ATOMIC);
2137 if (unlikely(!clone))
2138 return -ENOMEM;
2139
2140 /* For direct write, we need to keep the invariant that the skbs
2141 * we're dealing with need to be uncloned. Should uncloning fail
2142 * here, we need to free the just generated clone to unclone once
2143 * again.
2144 */
2145 ret = bpf_try_make_head_writable(skb);
2146 if (unlikely(ret)) {
2147 kfree_skb(clone);
2148 return -ENOMEM;
2149 }
2150
2151 return __bpf_redirect(clone, dev, flags);
2152 }
2153
2154 static const struct bpf_func_proto bpf_clone_redirect_proto = {
2155 .func = bpf_clone_redirect,
2156 .gpl_only = false,
2157 .ret_type = RET_INTEGER,
2158 .arg1_type = ARG_PTR_TO_CTX,
2159 .arg2_type = ARG_ANYTHING,
2160 .arg3_type = ARG_ANYTHING,
2161 };
2162
2163 DEFINE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
2164 EXPORT_PER_CPU_SYMBOL_GPL(bpf_redirect_info);
2165
BPF_CALL_2(bpf_redirect,u32,ifindex,u64,flags)2166 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
2167 {
2168 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2169
2170 if (unlikely(flags & ~(BPF_F_INGRESS)))
2171 return TC_ACT_SHOT;
2172
2173 ri->flags = flags;
2174 ri->tgt_index = ifindex;
2175
2176 return TC_ACT_REDIRECT;
2177 }
2178
skb_do_redirect(struct sk_buff * skb)2179 int skb_do_redirect(struct sk_buff *skb)
2180 {
2181 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2182 struct net_device *dev;
2183
2184 dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->tgt_index);
2185 ri->tgt_index = 0;
2186 if (unlikely(!dev)) {
2187 kfree_skb(skb);
2188 return -EINVAL;
2189 }
2190
2191 return __bpf_redirect(skb, dev, ri->flags);
2192 }
2193
2194 static const struct bpf_func_proto bpf_redirect_proto = {
2195 .func = bpf_redirect,
2196 .gpl_only = false,
2197 .ret_type = RET_INTEGER,
2198 .arg1_type = ARG_ANYTHING,
2199 .arg2_type = ARG_ANYTHING,
2200 };
2201
BPF_CALL_2(bpf_msg_apply_bytes,struct sk_msg *,msg,u32,bytes)2202 BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg *, msg, u32, bytes)
2203 {
2204 msg->apply_bytes = bytes;
2205 return 0;
2206 }
2207
2208 static const struct bpf_func_proto bpf_msg_apply_bytes_proto = {
2209 .func = bpf_msg_apply_bytes,
2210 .gpl_only = false,
2211 .ret_type = RET_INTEGER,
2212 .arg1_type = ARG_PTR_TO_CTX,
2213 .arg2_type = ARG_ANYTHING,
2214 };
2215
BPF_CALL_2(bpf_msg_cork_bytes,struct sk_msg *,msg,u32,bytes)2216 BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg *, msg, u32, bytes)
2217 {
2218 msg->cork_bytes = bytes;
2219 return 0;
2220 }
2221
sk_msg_reset_curr(struct sk_msg * msg)2222 static void sk_msg_reset_curr(struct sk_msg *msg)
2223 {
2224 u32 i = msg->sg.start;
2225 u32 len = 0;
2226
2227 do {
2228 len += sk_msg_elem(msg, i)->length;
2229 sk_msg_iter_var_next(i);
2230 if (len >= msg->sg.size)
2231 break;
2232 } while (i != msg->sg.end);
2233
2234 msg->sg.curr = i;
2235 msg->sg.copybreak = 0;
2236 }
2237
2238 static const struct bpf_func_proto bpf_msg_cork_bytes_proto = {
2239 .func = bpf_msg_cork_bytes,
2240 .gpl_only = false,
2241 .ret_type = RET_INTEGER,
2242 .arg1_type = ARG_PTR_TO_CTX,
2243 .arg2_type = ARG_ANYTHING,
2244 };
2245
BPF_CALL_4(bpf_msg_pull_data,struct sk_msg *,msg,u32,start,u32,end,u64,flags)2246 BPF_CALL_4(bpf_msg_pull_data, struct sk_msg *, msg, u32, start,
2247 u32, end, u64, flags)
2248 {
2249 u32 len = 0, offset = 0, copy = 0, poffset = 0, bytes = end - start;
2250 u32 first_sge, last_sge, i, shift, bytes_sg_total;
2251 struct scatterlist *sge;
2252 u8 *raw, *to, *from;
2253 struct page *page;
2254
2255 if (unlikely(flags || end <= start))
2256 return -EINVAL;
2257
2258 /* First find the starting scatterlist element */
2259 i = msg->sg.start;
2260 do {
2261 offset += len;
2262 len = sk_msg_elem(msg, i)->length;
2263 if (start < offset + len)
2264 break;
2265 sk_msg_iter_var_next(i);
2266 } while (i != msg->sg.end);
2267
2268 if (unlikely(start >= offset + len))
2269 return -EINVAL;
2270
2271 first_sge = i;
2272 /* The start may point into the sg element so we need to also
2273 * account for the headroom.
2274 */
2275 bytes_sg_total = start - offset + bytes;
2276 if (!msg->sg.copy[i] && bytes_sg_total <= len)
2277 goto out;
2278
2279 /* At this point we need to linearize multiple scatterlist
2280 * elements or a single shared page. Either way we need to
2281 * copy into a linear buffer exclusively owned by BPF. Then
2282 * place the buffer in the scatterlist and fixup the original
2283 * entries by removing the entries now in the linear buffer
2284 * and shifting the remaining entries. For now we do not try
2285 * to copy partial entries to avoid complexity of running out
2286 * of sg_entry slots. The downside is reading a single byte
2287 * will copy the entire sg entry.
2288 */
2289 do {
2290 copy += sk_msg_elem(msg, i)->length;
2291 sk_msg_iter_var_next(i);
2292 if (bytes_sg_total <= copy)
2293 break;
2294 } while (i != msg->sg.end);
2295 last_sge = i;
2296
2297 if (unlikely(bytes_sg_total > copy))
2298 return -EINVAL;
2299
2300 page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2301 get_order(copy));
2302 if (unlikely(!page))
2303 return -ENOMEM;
2304
2305 raw = page_address(page);
2306 i = first_sge;
2307 do {
2308 sge = sk_msg_elem(msg, i);
2309 from = sg_virt(sge);
2310 len = sge->length;
2311 to = raw + poffset;
2312
2313 memcpy(to, from, len);
2314 poffset += len;
2315 sge->length = 0;
2316 put_page(sg_page(sge));
2317
2318 sk_msg_iter_var_next(i);
2319 } while (i != last_sge);
2320
2321 sg_set_page(&msg->sg.data[first_sge], page, copy, 0);
2322
2323 /* To repair sg ring we need to shift entries. If we only
2324 * had a single entry though we can just replace it and
2325 * be done. Otherwise walk the ring and shift the entries.
2326 */
2327 WARN_ON_ONCE(last_sge == first_sge);
2328 shift = last_sge > first_sge ?
2329 last_sge - first_sge - 1 :
2330 NR_MSG_FRAG_IDS - first_sge + last_sge - 1;
2331 if (!shift)
2332 goto out;
2333
2334 i = first_sge;
2335 sk_msg_iter_var_next(i);
2336 do {
2337 u32 move_from;
2338
2339 if (i + shift >= NR_MSG_FRAG_IDS)
2340 move_from = i + shift - NR_MSG_FRAG_IDS;
2341 else
2342 move_from = i + shift;
2343 if (move_from == msg->sg.end)
2344 break;
2345
2346 msg->sg.data[i] = msg->sg.data[move_from];
2347 msg->sg.data[move_from].length = 0;
2348 msg->sg.data[move_from].page_link = 0;
2349 msg->sg.data[move_from].offset = 0;
2350 sk_msg_iter_var_next(i);
2351 } while (1);
2352
2353 msg->sg.end = msg->sg.end - shift > msg->sg.end ?
2354 msg->sg.end - shift + NR_MSG_FRAG_IDS :
2355 msg->sg.end - shift;
2356 out:
2357 sk_msg_reset_curr(msg);
2358 msg->data = sg_virt(&msg->sg.data[first_sge]) + start - offset;
2359 msg->data_end = msg->data + bytes;
2360 return 0;
2361 }
2362
2363 static const struct bpf_func_proto bpf_msg_pull_data_proto = {
2364 .func = bpf_msg_pull_data,
2365 .gpl_only = false,
2366 .ret_type = RET_INTEGER,
2367 .arg1_type = ARG_PTR_TO_CTX,
2368 .arg2_type = ARG_ANYTHING,
2369 .arg3_type = ARG_ANYTHING,
2370 .arg4_type = ARG_ANYTHING,
2371 };
2372
BPF_CALL_4(bpf_msg_push_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2373 BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start,
2374 u32, len, u64, flags)
2375 {
2376 struct scatterlist sge, nsge, nnsge, rsge = {0}, *psge;
2377 u32 new, i = 0, l = 0, space, copy = 0, offset = 0;
2378 u8 *raw, *to, *from;
2379 struct page *page;
2380
2381 if (unlikely(flags))
2382 return -EINVAL;
2383
2384 /* First find the starting scatterlist element */
2385 i = msg->sg.start;
2386 do {
2387 offset += l;
2388 l = sk_msg_elem(msg, i)->length;
2389
2390 if (start < offset + l)
2391 break;
2392 sk_msg_iter_var_next(i);
2393 } while (i != msg->sg.end);
2394
2395 if (start >= offset + l)
2396 return -EINVAL;
2397
2398 space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2399
2400 /* If no space available will fallback to copy, we need at
2401 * least one scatterlist elem available to push data into
2402 * when start aligns to the beginning of an element or two
2403 * when it falls inside an element. We handle the start equals
2404 * offset case because its the common case for inserting a
2405 * header.
2406 */
2407 if (!space || (space == 1 && start != offset))
2408 copy = msg->sg.data[i].length;
2409
2410 page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2411 get_order(copy + len));
2412 if (unlikely(!page))
2413 return -ENOMEM;
2414
2415 if (copy) {
2416 int front, back;
2417
2418 raw = page_address(page);
2419
2420 psge = sk_msg_elem(msg, i);
2421 front = start - offset;
2422 back = psge->length - front;
2423 from = sg_virt(psge);
2424
2425 if (front)
2426 memcpy(raw, from, front);
2427
2428 if (back) {
2429 from += front;
2430 to = raw + front + len;
2431
2432 memcpy(to, from, back);
2433 }
2434
2435 put_page(sg_page(psge));
2436 } else if (start - offset) {
2437 psge = sk_msg_elem(msg, i);
2438 rsge = sk_msg_elem_cpy(msg, i);
2439
2440 psge->length = start - offset;
2441 rsge.length -= psge->length;
2442 rsge.offset += start;
2443
2444 sk_msg_iter_var_next(i);
2445 sg_unmark_end(psge);
2446 sg_unmark_end(&rsge);
2447 sk_msg_iter_next(msg, end);
2448 }
2449
2450 /* Slot(s) to place newly allocated data */
2451 new = i;
2452
2453 /* Shift one or two slots as needed */
2454 if (!copy) {
2455 sge = sk_msg_elem_cpy(msg, i);
2456
2457 sk_msg_iter_var_next(i);
2458 sg_unmark_end(&sge);
2459 sk_msg_iter_next(msg, end);
2460
2461 nsge = sk_msg_elem_cpy(msg, i);
2462 if (rsge.length) {
2463 sk_msg_iter_var_next(i);
2464 nnsge = sk_msg_elem_cpy(msg, i);
2465 }
2466
2467 while (i != msg->sg.end) {
2468 msg->sg.data[i] = sge;
2469 sge = nsge;
2470 sk_msg_iter_var_next(i);
2471 if (rsge.length) {
2472 nsge = nnsge;
2473 nnsge = sk_msg_elem_cpy(msg, i);
2474 } else {
2475 nsge = sk_msg_elem_cpy(msg, i);
2476 }
2477 }
2478 }
2479
2480 /* Place newly allocated data buffer */
2481 sk_mem_charge(msg->sk, len);
2482 msg->sg.size += len;
2483 msg->sg.copy[new] = false;
2484 sg_set_page(&msg->sg.data[new], page, len + copy, 0);
2485 if (rsge.length) {
2486 get_page(sg_page(&rsge));
2487 sk_msg_iter_var_next(new);
2488 msg->sg.data[new] = rsge;
2489 }
2490
2491 sk_msg_reset_curr(msg);
2492 sk_msg_compute_data_pointers(msg);
2493 return 0;
2494 }
2495
2496 static const struct bpf_func_proto bpf_msg_push_data_proto = {
2497 .func = bpf_msg_push_data,
2498 .gpl_only = false,
2499 .ret_type = RET_INTEGER,
2500 .arg1_type = ARG_PTR_TO_CTX,
2501 .arg2_type = ARG_ANYTHING,
2502 .arg3_type = ARG_ANYTHING,
2503 .arg4_type = ARG_ANYTHING,
2504 };
2505
sk_msg_shift_left(struct sk_msg * msg,int i)2506 static void sk_msg_shift_left(struct sk_msg *msg, int i)
2507 {
2508 int prev;
2509
2510 do {
2511 prev = i;
2512 sk_msg_iter_var_next(i);
2513 msg->sg.data[prev] = msg->sg.data[i];
2514 } while (i != msg->sg.end);
2515
2516 sk_msg_iter_prev(msg, end);
2517 }
2518
sk_msg_shift_right(struct sk_msg * msg,int i)2519 static void sk_msg_shift_right(struct sk_msg *msg, int i)
2520 {
2521 struct scatterlist tmp, sge;
2522
2523 sk_msg_iter_next(msg, end);
2524 sge = sk_msg_elem_cpy(msg, i);
2525 sk_msg_iter_var_next(i);
2526 tmp = sk_msg_elem_cpy(msg, i);
2527
2528 while (i != msg->sg.end) {
2529 msg->sg.data[i] = sge;
2530 sk_msg_iter_var_next(i);
2531 sge = tmp;
2532 tmp = sk_msg_elem_cpy(msg, i);
2533 }
2534 }
2535
BPF_CALL_4(bpf_msg_pop_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2536 BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start,
2537 u32, len, u64, flags)
2538 {
2539 u32 i = 0, l = 0, space, offset = 0;
2540 u64 last = start + len;
2541 int pop;
2542
2543 if (unlikely(flags))
2544 return -EINVAL;
2545
2546 if (unlikely(len == 0))
2547 return 0;
2548
2549 /* First find the starting scatterlist element */
2550 i = msg->sg.start;
2551 do {
2552 offset += l;
2553 l = sk_msg_elem(msg, i)->length;
2554
2555 if (start < offset + l)
2556 break;
2557 sk_msg_iter_var_next(i);
2558 } while (i != msg->sg.end);
2559
2560 /* Bounds checks: start and pop must be inside message */
2561 if (start >= offset + l || last >= msg->sg.size)
2562 return -EINVAL;
2563
2564 space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2565
2566 pop = len;
2567 /* --------------| offset
2568 * -| start |-------- len -------|
2569 *
2570 * |----- a ----|-------- pop -------|----- b ----|
2571 * |______________________________________________| length
2572 *
2573 *
2574 * a: region at front of scatter element to save
2575 * b: region at back of scatter element to save when length > A + pop
2576 * pop: region to pop from element, same as input 'pop' here will be
2577 * decremented below per iteration.
2578 *
2579 * Two top-level cases to handle when start != offset, first B is non
2580 * zero and second B is zero corresponding to when a pop includes more
2581 * than one element.
2582 *
2583 * Then if B is non-zero AND there is no space allocate space and
2584 * compact A, B regions into page. If there is space shift ring to
2585 * the rigth free'ing the next element in ring to place B, leaving
2586 * A untouched except to reduce length.
2587 */
2588 if (start != offset) {
2589 struct scatterlist *nsge, *sge = sk_msg_elem(msg, i);
2590 int a = start;
2591 int b = sge->length - pop - a;
2592
2593 sk_msg_iter_var_next(i);
2594
2595 if (pop < sge->length - a) {
2596 if (space) {
2597 sge->length = a;
2598 sk_msg_shift_right(msg, i);
2599 nsge = sk_msg_elem(msg, i);
2600 get_page(sg_page(sge));
2601 sg_set_page(nsge,
2602 sg_page(sge),
2603 b, sge->offset + pop + a);
2604 } else {
2605 struct page *page, *orig;
2606 u8 *to, *from;
2607
2608 page = alloc_pages(__GFP_NOWARN |
2609 __GFP_COMP | GFP_ATOMIC,
2610 get_order(a + b));
2611 if (unlikely(!page))
2612 return -ENOMEM;
2613
2614 sge->length = a;
2615 orig = sg_page(sge);
2616 from = sg_virt(sge);
2617 to = page_address(page);
2618 memcpy(to, from, a);
2619 memcpy(to + a, from + a + pop, b);
2620 sg_set_page(sge, page, a + b, 0);
2621 put_page(orig);
2622 }
2623 pop = 0;
2624 } else if (pop >= sge->length - a) {
2625 pop -= (sge->length - a);
2626 sge->length = a;
2627 }
2628 }
2629
2630 /* From above the current layout _must_ be as follows,
2631 *
2632 * -| offset
2633 * -| start
2634 *
2635 * |---- pop ---|---------------- b ------------|
2636 * |____________________________________________| length
2637 *
2638 * Offset and start of the current msg elem are equal because in the
2639 * previous case we handled offset != start and either consumed the
2640 * entire element and advanced to the next element OR pop == 0.
2641 *
2642 * Two cases to handle here are first pop is less than the length
2643 * leaving some remainder b above. Simply adjust the element's layout
2644 * in this case. Or pop >= length of the element so that b = 0. In this
2645 * case advance to next element decrementing pop.
2646 */
2647 while (pop) {
2648 struct scatterlist *sge = sk_msg_elem(msg, i);
2649
2650 if (pop < sge->length) {
2651 sge->length -= pop;
2652 sge->offset += pop;
2653 pop = 0;
2654 } else {
2655 pop -= sge->length;
2656 sk_msg_shift_left(msg, i);
2657 }
2658 sk_msg_iter_var_next(i);
2659 }
2660
2661 sk_mem_uncharge(msg->sk, len - pop);
2662 msg->sg.size -= (len - pop);
2663 sk_msg_reset_curr(msg);
2664 sk_msg_compute_data_pointers(msg);
2665 return 0;
2666 }
2667
2668 static const struct bpf_func_proto bpf_msg_pop_data_proto = {
2669 .func = bpf_msg_pop_data,
2670 .gpl_only = false,
2671 .ret_type = RET_INTEGER,
2672 .arg1_type = ARG_PTR_TO_CTX,
2673 .arg2_type = ARG_ANYTHING,
2674 .arg3_type = ARG_ANYTHING,
2675 .arg4_type = ARG_ANYTHING,
2676 };
2677
BPF_CALL_1(bpf_get_cgroup_classid,const struct sk_buff *,skb)2678 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
2679 {
2680 return task_get_classid(skb);
2681 }
2682
2683 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
2684 .func = bpf_get_cgroup_classid,
2685 .gpl_only = false,
2686 .ret_type = RET_INTEGER,
2687 .arg1_type = ARG_PTR_TO_CTX,
2688 };
2689
BPF_CALL_1(bpf_get_route_realm,const struct sk_buff *,skb)2690 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
2691 {
2692 return dst_tclassid(skb);
2693 }
2694
2695 static const struct bpf_func_proto bpf_get_route_realm_proto = {
2696 .func = bpf_get_route_realm,
2697 .gpl_only = false,
2698 .ret_type = RET_INTEGER,
2699 .arg1_type = ARG_PTR_TO_CTX,
2700 };
2701
BPF_CALL_1(bpf_get_hash_recalc,struct sk_buff *,skb)2702 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
2703 {
2704 /* If skb_clear_hash() was called due to mangling, we can
2705 * trigger SW recalculation here. Later access to hash
2706 * can then use the inline skb->hash via context directly
2707 * instead of calling this helper again.
2708 */
2709 return skb_get_hash(skb);
2710 }
2711
2712 static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
2713 .func = bpf_get_hash_recalc,
2714 .gpl_only = false,
2715 .ret_type = RET_INTEGER,
2716 .arg1_type = ARG_PTR_TO_CTX,
2717 };
2718
BPF_CALL_1(bpf_set_hash_invalid,struct sk_buff *,skb)2719 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
2720 {
2721 /* After all direct packet write, this can be used once for
2722 * triggering a lazy recalc on next skb_get_hash() invocation.
2723 */
2724 skb_clear_hash(skb);
2725 return 0;
2726 }
2727
2728 static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
2729 .func = bpf_set_hash_invalid,
2730 .gpl_only = false,
2731 .ret_type = RET_INTEGER,
2732 .arg1_type = ARG_PTR_TO_CTX,
2733 };
2734
BPF_CALL_2(bpf_set_hash,struct sk_buff *,skb,u32,hash)2735 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
2736 {
2737 /* Set user specified hash as L4(+), so that it gets returned
2738 * on skb_get_hash() call unless BPF prog later on triggers a
2739 * skb_clear_hash().
2740 */
2741 __skb_set_sw_hash(skb, hash, true);
2742 return 0;
2743 }
2744
2745 static const struct bpf_func_proto bpf_set_hash_proto = {
2746 .func = bpf_set_hash,
2747 .gpl_only = false,
2748 .ret_type = RET_INTEGER,
2749 .arg1_type = ARG_PTR_TO_CTX,
2750 .arg2_type = ARG_ANYTHING,
2751 };
2752
BPF_CALL_3(bpf_skb_vlan_push,struct sk_buff *,skb,__be16,vlan_proto,u16,vlan_tci)2753 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
2754 u16, vlan_tci)
2755 {
2756 int ret;
2757
2758 if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
2759 vlan_proto != htons(ETH_P_8021AD)))
2760 vlan_proto = htons(ETH_P_8021Q);
2761
2762 bpf_push_mac_rcsum(skb);
2763 ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
2764 bpf_pull_mac_rcsum(skb);
2765
2766 bpf_compute_data_pointers(skb);
2767 return ret;
2768 }
2769
2770 static const struct bpf_func_proto bpf_skb_vlan_push_proto = {
2771 .func = bpf_skb_vlan_push,
2772 .gpl_only = false,
2773 .ret_type = RET_INTEGER,
2774 .arg1_type = ARG_PTR_TO_CTX,
2775 .arg2_type = ARG_ANYTHING,
2776 .arg3_type = ARG_ANYTHING,
2777 };
2778
BPF_CALL_1(bpf_skb_vlan_pop,struct sk_buff *,skb)2779 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
2780 {
2781 int ret;
2782
2783 bpf_push_mac_rcsum(skb);
2784 ret = skb_vlan_pop(skb);
2785 bpf_pull_mac_rcsum(skb);
2786
2787 bpf_compute_data_pointers(skb);
2788 return ret;
2789 }
2790
2791 static const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
2792 .func = bpf_skb_vlan_pop,
2793 .gpl_only = false,
2794 .ret_type = RET_INTEGER,
2795 .arg1_type = ARG_PTR_TO_CTX,
2796 };
2797
bpf_skb_generic_push(struct sk_buff * skb,u32 off,u32 len)2798 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
2799 {
2800 /* Caller already did skb_cow() with len as headroom,
2801 * so no need to do it here.
2802 */
2803 skb_push(skb, len);
2804 memmove(skb->data, skb->data + len, off);
2805 memset(skb->data + off, 0, len);
2806
2807 /* No skb_postpush_rcsum(skb, skb->data + off, len)
2808 * needed here as it does not change the skb->csum
2809 * result for checksum complete when summing over
2810 * zeroed blocks.
2811 */
2812 return 0;
2813 }
2814
bpf_skb_generic_pop(struct sk_buff * skb,u32 off,u32 len)2815 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
2816 {
2817 void *old_data;
2818
2819 /* skb_ensure_writable() is not needed here, as we're
2820 * already working on an uncloned skb.
2821 */
2822 if (unlikely(!pskb_may_pull(skb, off + len)))
2823 return -ENOMEM;
2824
2825 old_data = skb->data;
2826 __skb_pull(skb, len);
2827 skb_postpull_rcsum(skb, old_data + off, len);
2828 memmove(skb->data, old_data, off);
2829
2830 return 0;
2831 }
2832
bpf_skb_net_hdr_push(struct sk_buff * skb,u32 off,u32 len)2833 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
2834 {
2835 bool trans_same = skb->transport_header == skb->network_header;
2836 int ret;
2837
2838 /* There's no need for __skb_push()/__skb_pull() pair to
2839 * get to the start of the mac header as we're guaranteed
2840 * to always start from here under eBPF.
2841 */
2842 ret = bpf_skb_generic_push(skb, off, len);
2843 if (likely(!ret)) {
2844 skb->mac_header -= len;
2845 skb->network_header -= len;
2846 if (trans_same)
2847 skb->transport_header = skb->network_header;
2848 }
2849
2850 return ret;
2851 }
2852
bpf_skb_net_hdr_pop(struct sk_buff * skb,u32 off,u32 len)2853 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
2854 {
2855 bool trans_same = skb->transport_header == skb->network_header;
2856 int ret;
2857
2858 /* Same here, __skb_push()/__skb_pull() pair not needed. */
2859 ret = bpf_skb_generic_pop(skb, off, len);
2860 if (likely(!ret)) {
2861 skb->mac_header += len;
2862 skb->network_header += len;
2863 if (trans_same)
2864 skb->transport_header = skb->network_header;
2865 }
2866
2867 return ret;
2868 }
2869
bpf_skb_proto_4_to_6(struct sk_buff * skb)2870 static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
2871 {
2872 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
2873 u32 off = skb_mac_header_len(skb);
2874 int ret;
2875
2876 if (skb_is_gso(skb) && !skb_is_gso_tcp(skb))
2877 return -ENOTSUPP;
2878
2879 ret = skb_cow(skb, len_diff);
2880 if (unlikely(ret < 0))
2881 return ret;
2882
2883 ret = bpf_skb_net_hdr_push(skb, off, len_diff);
2884 if (unlikely(ret < 0))
2885 return ret;
2886
2887 if (skb_is_gso(skb)) {
2888 struct skb_shared_info *shinfo = skb_shinfo(skb);
2889
2890 /* SKB_GSO_TCPV4 needs to be changed into
2891 * SKB_GSO_TCPV6.
2892 */
2893 if (shinfo->gso_type & SKB_GSO_TCPV4) {
2894 shinfo->gso_type &= ~SKB_GSO_TCPV4;
2895 shinfo->gso_type |= SKB_GSO_TCPV6;
2896 }
2897
2898 /* Header must be checked, and gso_segs recomputed. */
2899 shinfo->gso_type |= SKB_GSO_DODGY;
2900 shinfo->gso_segs = 0;
2901 }
2902
2903 skb->protocol = htons(ETH_P_IPV6);
2904 skb_clear_hash(skb);
2905
2906 return 0;
2907 }
2908
bpf_skb_proto_6_to_4(struct sk_buff * skb)2909 static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
2910 {
2911 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
2912 u32 off = skb_mac_header_len(skb);
2913 int ret;
2914
2915 if (skb_is_gso(skb) && !skb_is_gso_tcp(skb))
2916 return -ENOTSUPP;
2917
2918 ret = skb_unclone(skb, GFP_ATOMIC);
2919 if (unlikely(ret < 0))
2920 return ret;
2921
2922 ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
2923 if (unlikely(ret < 0))
2924 return ret;
2925
2926 if (skb_is_gso(skb)) {
2927 struct skb_shared_info *shinfo = skb_shinfo(skb);
2928
2929 /* SKB_GSO_TCPV6 needs to be changed into
2930 * SKB_GSO_TCPV4.
2931 */
2932 if (shinfo->gso_type & SKB_GSO_TCPV6) {
2933 shinfo->gso_type &= ~SKB_GSO_TCPV6;
2934 shinfo->gso_type |= SKB_GSO_TCPV4;
2935 }
2936
2937 /* Header must be checked, and gso_segs recomputed. */
2938 shinfo->gso_type |= SKB_GSO_DODGY;
2939 shinfo->gso_segs = 0;
2940 }
2941
2942 skb->protocol = htons(ETH_P_IP);
2943 skb_clear_hash(skb);
2944
2945 return 0;
2946 }
2947
bpf_skb_proto_xlat(struct sk_buff * skb,__be16 to_proto)2948 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
2949 {
2950 __be16 from_proto = skb->protocol;
2951
2952 if (from_proto == htons(ETH_P_IP) &&
2953 to_proto == htons(ETH_P_IPV6))
2954 return bpf_skb_proto_4_to_6(skb);
2955
2956 if (from_proto == htons(ETH_P_IPV6) &&
2957 to_proto == htons(ETH_P_IP))
2958 return bpf_skb_proto_6_to_4(skb);
2959
2960 return -ENOTSUPP;
2961 }
2962
BPF_CALL_3(bpf_skb_change_proto,struct sk_buff *,skb,__be16,proto,u64,flags)2963 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
2964 u64, flags)
2965 {
2966 int ret;
2967
2968 if (unlikely(flags))
2969 return -EINVAL;
2970
2971 /* General idea is that this helper does the basic groundwork
2972 * needed for changing the protocol, and eBPF program fills the
2973 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
2974 * and other helpers, rather than passing a raw buffer here.
2975 *
2976 * The rationale is to keep this minimal and without a need to
2977 * deal with raw packet data. F.e. even if we would pass buffers
2978 * here, the program still needs to call the bpf_lX_csum_replace()
2979 * helpers anyway. Plus, this way we keep also separation of
2980 * concerns, since f.e. bpf_skb_store_bytes() should only take
2981 * care of stores.
2982 *
2983 * Currently, additional options and extension header space are
2984 * not supported, but flags register is reserved so we can adapt
2985 * that. For offloads, we mark packet as dodgy, so that headers
2986 * need to be verified first.
2987 */
2988 ret = bpf_skb_proto_xlat(skb, proto);
2989 bpf_compute_data_pointers(skb);
2990 return ret;
2991 }
2992
2993 static const struct bpf_func_proto bpf_skb_change_proto_proto = {
2994 .func = bpf_skb_change_proto,
2995 .gpl_only = false,
2996 .ret_type = RET_INTEGER,
2997 .arg1_type = ARG_PTR_TO_CTX,
2998 .arg2_type = ARG_ANYTHING,
2999 .arg3_type = ARG_ANYTHING,
3000 };
3001
BPF_CALL_2(bpf_skb_change_type,struct sk_buff *,skb,u32,pkt_type)3002 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
3003 {
3004 /* We only allow a restricted subset to be changed for now. */
3005 if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
3006 !skb_pkt_type_ok(pkt_type)))
3007 return -EINVAL;
3008
3009 skb->pkt_type = pkt_type;
3010 return 0;
3011 }
3012
3013 static const struct bpf_func_proto bpf_skb_change_type_proto = {
3014 .func = bpf_skb_change_type,
3015 .gpl_only = false,
3016 .ret_type = RET_INTEGER,
3017 .arg1_type = ARG_PTR_TO_CTX,
3018 .arg2_type = ARG_ANYTHING,
3019 };
3020
bpf_skb_net_base_len(const struct sk_buff * skb)3021 static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
3022 {
3023 switch (skb->protocol) {
3024 case htons(ETH_P_IP):
3025 return sizeof(struct iphdr);
3026 case htons(ETH_P_IPV6):
3027 return sizeof(struct ipv6hdr);
3028 default:
3029 return ~0U;
3030 }
3031 }
3032
3033 #define BPF_F_ADJ_ROOM_ENCAP_L3_MASK (BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 | \
3034 BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3035
3036 #define BPF_F_ADJ_ROOM_MASK (BPF_F_ADJ_ROOM_FIXED_GSO | \
3037 BPF_F_ADJ_ROOM_ENCAP_L3_MASK | \
3038 BPF_F_ADJ_ROOM_ENCAP_L4_GRE | \
3039 BPF_F_ADJ_ROOM_ENCAP_L4_UDP | \
3040 BPF_F_ADJ_ROOM_ENCAP_L2( \
3041 BPF_ADJ_ROOM_ENCAP_L2_MASK))
3042
bpf_skb_net_grow(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3043 static int bpf_skb_net_grow(struct sk_buff *skb, u32 off, u32 len_diff,
3044 u64 flags)
3045 {
3046 u8 inner_mac_len = flags >> BPF_ADJ_ROOM_ENCAP_L2_SHIFT;
3047 bool encap = flags & BPF_F_ADJ_ROOM_ENCAP_L3_MASK;
3048 u16 mac_len = 0, inner_net = 0, inner_trans = 0;
3049 unsigned int gso_type = SKB_GSO_DODGY;
3050 int ret;
3051
3052 if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3053 /* udp gso_size delineates datagrams, only allow if fixed */
3054 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3055 !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3056 return -ENOTSUPP;
3057 }
3058
3059 ret = skb_cow_head(skb, len_diff);
3060 if (unlikely(ret < 0))
3061 return ret;
3062
3063 if (encap) {
3064 if (skb->protocol != htons(ETH_P_IP) &&
3065 skb->protocol != htons(ETH_P_IPV6))
3066 return -ENOTSUPP;
3067
3068 if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 &&
3069 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3070 return -EINVAL;
3071
3072 if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE &&
3073 flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3074 return -EINVAL;
3075
3076 if (skb->encapsulation)
3077 return -EALREADY;
3078
3079 mac_len = skb->network_header - skb->mac_header;
3080 inner_net = skb->network_header;
3081 if (inner_mac_len > len_diff)
3082 return -EINVAL;
3083 inner_trans = skb->transport_header;
3084 }
3085
3086 ret = bpf_skb_net_hdr_push(skb, off, len_diff);
3087 if (unlikely(ret < 0))
3088 return ret;
3089
3090 if (encap) {
3091 skb->inner_mac_header = inner_net - inner_mac_len;
3092 skb->inner_network_header = inner_net;
3093 skb->inner_transport_header = inner_trans;
3094 skb_set_inner_protocol(skb, skb->protocol);
3095
3096 skb->encapsulation = 1;
3097 skb_set_network_header(skb, mac_len);
3098
3099 if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3100 gso_type |= SKB_GSO_UDP_TUNNEL;
3101 else if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE)
3102 gso_type |= SKB_GSO_GRE;
3103 else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3104 gso_type |= SKB_GSO_IPXIP6;
3105 else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3106 gso_type |= SKB_GSO_IPXIP4;
3107
3108 if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE ||
3109 flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP) {
3110 int nh_len = flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 ?
3111 sizeof(struct ipv6hdr) :
3112 sizeof(struct iphdr);
3113
3114 skb_set_transport_header(skb, mac_len + nh_len);
3115 }
3116
3117 /* Match skb->protocol to new outer l3 protocol */
3118 if (skb->protocol == htons(ETH_P_IP) &&
3119 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3120 skb->protocol = htons(ETH_P_IPV6);
3121 else if (skb->protocol == htons(ETH_P_IPV6) &&
3122 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3123 skb->protocol = htons(ETH_P_IP);
3124 }
3125
3126 if (skb_is_gso(skb)) {
3127 struct skb_shared_info *shinfo = skb_shinfo(skb);
3128
3129 /* Due to header grow, MSS needs to be downgraded. */
3130 if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3131 skb_decrease_gso_size(shinfo, len_diff);
3132
3133 /* Header must be checked, and gso_segs recomputed. */
3134 shinfo->gso_type |= gso_type;
3135 shinfo->gso_segs = 0;
3136 }
3137
3138 return 0;
3139 }
3140
bpf_skb_net_shrink(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3141 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 off, u32 len_diff,
3142 u64 flags)
3143 {
3144 int ret;
3145
3146 if (flags & ~BPF_F_ADJ_ROOM_FIXED_GSO)
3147 return -EINVAL;
3148
3149 if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3150 /* udp gso_size delineates datagrams, only allow if fixed */
3151 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3152 !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3153 return -ENOTSUPP;
3154 }
3155
3156 ret = skb_unclone(skb, GFP_ATOMIC);
3157 if (unlikely(ret < 0))
3158 return ret;
3159
3160 ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
3161 if (unlikely(ret < 0))
3162 return ret;
3163
3164 if (skb_is_gso(skb)) {
3165 struct skb_shared_info *shinfo = skb_shinfo(skb);
3166
3167 /* Due to header shrink, MSS can be upgraded. */
3168 if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3169 skb_increase_gso_size(shinfo, len_diff);
3170
3171 /* Header must be checked, and gso_segs recomputed. */
3172 shinfo->gso_type |= SKB_GSO_DODGY;
3173 shinfo->gso_segs = 0;
3174 }
3175
3176 return 0;
3177 }
3178
3179 #define BPF_SKB_MAX_LEN SKB_MAX_ALLOC
3180
BPF_CALL_4(bpf_skb_adjust_room,struct sk_buff *,skb,s32,len_diff,u32,mode,u64,flags)3181 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
3182 u32, mode, u64, flags)
3183 {
3184 u32 len_cur, len_diff_abs = abs(len_diff);
3185 u32 len_min = bpf_skb_net_base_len(skb);
3186 u32 len_max = BPF_SKB_MAX_LEN;
3187 __be16 proto = skb->protocol;
3188 bool shrink = len_diff < 0;
3189 u32 off;
3190 int ret;
3191
3192 if (unlikely(flags & ~BPF_F_ADJ_ROOM_MASK))
3193 return -EINVAL;
3194 if (unlikely(len_diff_abs > 0xfffU))
3195 return -EFAULT;
3196 if (unlikely(proto != htons(ETH_P_IP) &&
3197 proto != htons(ETH_P_IPV6)))
3198 return -ENOTSUPP;
3199
3200 off = skb_mac_header_len(skb);
3201 switch (mode) {
3202 case BPF_ADJ_ROOM_NET:
3203 off += bpf_skb_net_base_len(skb);
3204 break;
3205 case BPF_ADJ_ROOM_MAC:
3206 break;
3207 default:
3208 return -ENOTSUPP;
3209 }
3210
3211 len_cur = skb->len - skb_network_offset(skb);
3212 if ((shrink && (len_diff_abs >= len_cur ||
3213 len_cur - len_diff_abs < len_min)) ||
3214 (!shrink && (skb->len + len_diff_abs > len_max &&
3215 !skb_is_gso(skb))))
3216 return -ENOTSUPP;
3217
3218 ret = shrink ? bpf_skb_net_shrink(skb, off, len_diff_abs, flags) :
3219 bpf_skb_net_grow(skb, off, len_diff_abs, flags);
3220
3221 bpf_compute_data_pointers(skb);
3222 return ret;
3223 }
3224
3225 static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
3226 .func = bpf_skb_adjust_room,
3227 .gpl_only = false,
3228 .ret_type = RET_INTEGER,
3229 .arg1_type = ARG_PTR_TO_CTX,
3230 .arg2_type = ARG_ANYTHING,
3231 .arg3_type = ARG_ANYTHING,
3232 .arg4_type = ARG_ANYTHING,
3233 };
3234
__bpf_skb_min_len(const struct sk_buff * skb)3235 static u32 __bpf_skb_min_len(const struct sk_buff *skb)
3236 {
3237 u32 min_len = skb_network_offset(skb);
3238
3239 if (skb_transport_header_was_set(skb))
3240 min_len = skb_transport_offset(skb);
3241 if (skb->ip_summed == CHECKSUM_PARTIAL)
3242 min_len = skb_checksum_start_offset(skb) +
3243 skb->csum_offset + sizeof(__sum16);
3244 return min_len;
3245 }
3246
bpf_skb_grow_rcsum(struct sk_buff * skb,unsigned int new_len)3247 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
3248 {
3249 unsigned int old_len = skb->len;
3250 int ret;
3251
3252 ret = __skb_grow_rcsum(skb, new_len);
3253 if (!ret)
3254 memset(skb->data + old_len, 0, new_len - old_len);
3255 return ret;
3256 }
3257
bpf_skb_trim_rcsum(struct sk_buff * skb,unsigned int new_len)3258 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
3259 {
3260 return __skb_trim_rcsum(skb, new_len);
3261 }
3262
__bpf_skb_change_tail(struct sk_buff * skb,u32 new_len,u64 flags)3263 static inline int __bpf_skb_change_tail(struct sk_buff *skb, u32 new_len,
3264 u64 flags)
3265 {
3266 u32 max_len = BPF_SKB_MAX_LEN;
3267 u32 min_len = __bpf_skb_min_len(skb);
3268 int ret;
3269
3270 if (unlikely(flags || new_len > max_len || new_len < min_len))
3271 return -EINVAL;
3272 if (skb->encapsulation)
3273 return -ENOTSUPP;
3274
3275 /* The basic idea of this helper is that it's performing the
3276 * needed work to either grow or trim an skb, and eBPF program
3277 * rewrites the rest via helpers like bpf_skb_store_bytes(),
3278 * bpf_lX_csum_replace() and others rather than passing a raw
3279 * buffer here. This one is a slow path helper and intended
3280 * for replies with control messages.
3281 *
3282 * Like in bpf_skb_change_proto(), we want to keep this rather
3283 * minimal and without protocol specifics so that we are able
3284 * to separate concerns as in bpf_skb_store_bytes() should only
3285 * be the one responsible for writing buffers.
3286 *
3287 * It's really expected to be a slow path operation here for
3288 * control message replies, so we're implicitly linearizing,
3289 * uncloning and drop offloads from the skb by this.
3290 */
3291 ret = __bpf_try_make_writable(skb, skb->len);
3292 if (!ret) {
3293 if (new_len > skb->len)
3294 ret = bpf_skb_grow_rcsum(skb, new_len);
3295 else if (new_len < skb->len)
3296 ret = bpf_skb_trim_rcsum(skb, new_len);
3297 if (!ret && skb_is_gso(skb))
3298 skb_gso_reset(skb);
3299 }
3300 return ret;
3301 }
3302
BPF_CALL_3(bpf_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3303 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3304 u64, flags)
3305 {
3306 int ret = __bpf_skb_change_tail(skb, new_len, flags);
3307
3308 bpf_compute_data_pointers(skb);
3309 return ret;
3310 }
3311
3312 static const struct bpf_func_proto bpf_skb_change_tail_proto = {
3313 .func = bpf_skb_change_tail,
3314 .gpl_only = false,
3315 .ret_type = RET_INTEGER,
3316 .arg1_type = ARG_PTR_TO_CTX,
3317 .arg2_type = ARG_ANYTHING,
3318 .arg3_type = ARG_ANYTHING,
3319 };
3320
BPF_CALL_3(sk_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3321 BPF_CALL_3(sk_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3322 u64, flags)
3323 {
3324 int ret = __bpf_skb_change_tail(skb, new_len, flags);
3325
3326 bpf_compute_data_end_sk_skb(skb);
3327 return ret;
3328 }
3329
3330 static const struct bpf_func_proto sk_skb_change_tail_proto = {
3331 .func = sk_skb_change_tail,
3332 .gpl_only = false,
3333 .ret_type = RET_INTEGER,
3334 .arg1_type = ARG_PTR_TO_CTX,
3335 .arg2_type = ARG_ANYTHING,
3336 .arg3_type = ARG_ANYTHING,
3337 };
3338
__bpf_skb_change_head(struct sk_buff * skb,u32 head_room,u64 flags)3339 static inline int __bpf_skb_change_head(struct sk_buff *skb, u32 head_room,
3340 u64 flags)
3341 {
3342 u32 max_len = BPF_SKB_MAX_LEN;
3343 u32 new_len = skb->len + head_room;
3344 int ret;
3345
3346 if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
3347 new_len < skb->len))
3348 return -EINVAL;
3349
3350 ret = skb_cow(skb, head_room);
3351 if (likely(!ret)) {
3352 /* Idea for this helper is that we currently only
3353 * allow to expand on mac header. This means that
3354 * skb->protocol network header, etc, stay as is.
3355 * Compared to bpf_skb_change_tail(), we're more
3356 * flexible due to not needing to linearize or
3357 * reset GSO. Intention for this helper is to be
3358 * used by an L3 skb that needs to push mac header
3359 * for redirection into L2 device.
3360 */
3361 __skb_push(skb, head_room);
3362 memset(skb->data, 0, head_room);
3363 skb_reset_mac_header(skb);
3364 skb_reset_mac_len(skb);
3365 }
3366
3367 return ret;
3368 }
3369
BPF_CALL_3(bpf_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3370 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
3371 u64, flags)
3372 {
3373 int ret = __bpf_skb_change_head(skb, head_room, flags);
3374
3375 bpf_compute_data_pointers(skb);
3376 return ret;
3377 }
3378
3379 static const struct bpf_func_proto bpf_skb_change_head_proto = {
3380 .func = bpf_skb_change_head,
3381 .gpl_only = false,
3382 .ret_type = RET_INTEGER,
3383 .arg1_type = ARG_PTR_TO_CTX,
3384 .arg2_type = ARG_ANYTHING,
3385 .arg3_type = ARG_ANYTHING,
3386 };
3387
BPF_CALL_3(sk_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3388 BPF_CALL_3(sk_skb_change_head, struct sk_buff *, skb, u32, head_room,
3389 u64, flags)
3390 {
3391 int ret = __bpf_skb_change_head(skb, head_room, flags);
3392
3393 bpf_compute_data_end_sk_skb(skb);
3394 return ret;
3395 }
3396
3397 static const struct bpf_func_proto sk_skb_change_head_proto = {
3398 .func = sk_skb_change_head,
3399 .gpl_only = false,
3400 .ret_type = RET_INTEGER,
3401 .arg1_type = ARG_PTR_TO_CTX,
3402 .arg2_type = ARG_ANYTHING,
3403 .arg3_type = ARG_ANYTHING,
3404 };
xdp_get_metalen(const struct xdp_buff * xdp)3405 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
3406 {
3407 return xdp_data_meta_unsupported(xdp) ? 0 :
3408 xdp->data - xdp->data_meta;
3409 }
3410
BPF_CALL_2(bpf_xdp_adjust_head,struct xdp_buff *,xdp,int,offset)3411 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
3412 {
3413 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
3414 unsigned long metalen = xdp_get_metalen(xdp);
3415 void *data_start = xdp_frame_end + metalen;
3416 void *data = xdp->data + offset;
3417
3418 if (unlikely(data < data_start ||
3419 data > xdp->data_end - ETH_HLEN))
3420 return -EINVAL;
3421
3422 if (metalen)
3423 memmove(xdp->data_meta + offset,
3424 xdp->data_meta, metalen);
3425 xdp->data_meta += offset;
3426 xdp->data = data;
3427
3428 return 0;
3429 }
3430
3431 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
3432 .func = bpf_xdp_adjust_head,
3433 .gpl_only = false,
3434 .ret_type = RET_INTEGER,
3435 .arg1_type = ARG_PTR_TO_CTX,
3436 .arg2_type = ARG_ANYTHING,
3437 };
3438
BPF_CALL_2(bpf_xdp_adjust_tail,struct xdp_buff *,xdp,int,offset)3439 BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset)
3440 {
3441 void *data_end = xdp->data_end + offset;
3442
3443 /* only shrinking is allowed for now. */
3444 if (unlikely(offset >= 0))
3445 return -EINVAL;
3446
3447 if (unlikely(data_end < xdp->data + ETH_HLEN))
3448 return -EINVAL;
3449
3450 xdp->data_end = data_end;
3451
3452 return 0;
3453 }
3454
3455 static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = {
3456 .func = bpf_xdp_adjust_tail,
3457 .gpl_only = false,
3458 .ret_type = RET_INTEGER,
3459 .arg1_type = ARG_PTR_TO_CTX,
3460 .arg2_type = ARG_ANYTHING,
3461 };
3462
BPF_CALL_2(bpf_xdp_adjust_meta,struct xdp_buff *,xdp,int,offset)3463 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
3464 {
3465 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
3466 void *meta = xdp->data_meta + offset;
3467 unsigned long metalen = xdp->data - meta;
3468
3469 if (xdp_data_meta_unsupported(xdp))
3470 return -ENOTSUPP;
3471 if (unlikely(meta < xdp_frame_end ||
3472 meta > xdp->data))
3473 return -EINVAL;
3474 if (unlikely((metalen & (sizeof(__u32) - 1)) ||
3475 (metalen > 32)))
3476 return -EACCES;
3477
3478 xdp->data_meta = meta;
3479
3480 return 0;
3481 }
3482
3483 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
3484 .func = bpf_xdp_adjust_meta,
3485 .gpl_only = false,
3486 .ret_type = RET_INTEGER,
3487 .arg1_type = ARG_PTR_TO_CTX,
3488 .arg2_type = ARG_ANYTHING,
3489 };
3490
__bpf_tx_xdp(struct net_device * dev,struct bpf_map * map,struct xdp_buff * xdp,u32 index)3491 static int __bpf_tx_xdp(struct net_device *dev,
3492 struct bpf_map *map,
3493 struct xdp_buff *xdp,
3494 u32 index)
3495 {
3496 struct xdp_frame *xdpf;
3497 int err, sent;
3498
3499 if (!dev->netdev_ops->ndo_xdp_xmit) {
3500 return -EOPNOTSUPP;
3501 }
3502
3503 err = xdp_ok_fwd_dev(dev, xdp->data_end - xdp->data);
3504 if (unlikely(err))
3505 return err;
3506
3507 xdpf = convert_to_xdp_frame(xdp);
3508 if (unlikely(!xdpf))
3509 return -EOVERFLOW;
3510
3511 sent = dev->netdev_ops->ndo_xdp_xmit(dev, 1, &xdpf, XDP_XMIT_FLUSH);
3512 if (sent <= 0)
3513 return sent;
3514 return 0;
3515 }
3516
3517 static noinline int
xdp_do_redirect_slow(struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog,struct bpf_redirect_info * ri)3518 xdp_do_redirect_slow(struct net_device *dev, struct xdp_buff *xdp,
3519 struct bpf_prog *xdp_prog, struct bpf_redirect_info *ri)
3520 {
3521 struct net_device *fwd;
3522 u32 index = ri->tgt_index;
3523 int err;
3524
3525 fwd = dev_get_by_index_rcu(dev_net(dev), index);
3526 ri->tgt_index = 0;
3527 if (unlikely(!fwd)) {
3528 err = -EINVAL;
3529 goto err;
3530 }
3531
3532 err = __bpf_tx_xdp(fwd, NULL, xdp, 0);
3533 if (unlikely(err))
3534 goto err;
3535
3536 _trace_xdp_redirect(dev, xdp_prog, index);
3537 return 0;
3538 err:
3539 _trace_xdp_redirect_err(dev, xdp_prog, index, err);
3540 return err;
3541 }
3542
__bpf_tx_xdp_map(struct net_device * dev_rx,void * fwd,struct bpf_map * map,struct xdp_buff * xdp,u32 index)3543 static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd,
3544 struct bpf_map *map,
3545 struct xdp_buff *xdp,
3546 u32 index)
3547 {
3548 int err;
3549
3550 switch (map->map_type) {
3551 case BPF_MAP_TYPE_DEVMAP:
3552 case BPF_MAP_TYPE_DEVMAP_HASH: {
3553 struct bpf_dtab_netdev *dst = fwd;
3554
3555 err = dev_map_enqueue(dst, xdp, dev_rx);
3556 if (unlikely(err))
3557 return err;
3558 break;
3559 }
3560 case BPF_MAP_TYPE_CPUMAP: {
3561 struct bpf_cpu_map_entry *rcpu = fwd;
3562
3563 err = cpu_map_enqueue(rcpu, xdp, dev_rx);
3564 if (unlikely(err))
3565 return err;
3566 break;
3567 }
3568 case BPF_MAP_TYPE_XSKMAP: {
3569 struct xdp_sock *xs = fwd;
3570
3571 err = __xsk_map_redirect(map, xdp, xs);
3572 return err;
3573 }
3574 default:
3575 return -EBADRQC;
3576 }
3577 return 0;
3578 }
3579
xdp_do_flush_map(void)3580 void xdp_do_flush_map(void)
3581 {
3582 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
3583 struct bpf_map *map = ri->map_to_flush;
3584
3585 ri->map_to_flush = NULL;
3586 if (map) {
3587 switch (map->map_type) {
3588 case BPF_MAP_TYPE_DEVMAP:
3589 case BPF_MAP_TYPE_DEVMAP_HASH:
3590 __dev_map_flush(map);
3591 break;
3592 case BPF_MAP_TYPE_CPUMAP:
3593 __cpu_map_flush(map);
3594 break;
3595 case BPF_MAP_TYPE_XSKMAP:
3596 __xsk_map_flush(map);
3597 break;
3598 default:
3599 break;
3600 }
3601 }
3602 }
3603 EXPORT_SYMBOL_GPL(xdp_do_flush_map);
3604
__xdp_map_lookup_elem(struct bpf_map * map,u32 index)3605 static inline void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index)
3606 {
3607 switch (map->map_type) {
3608 case BPF_MAP_TYPE_DEVMAP:
3609 return __dev_map_lookup_elem(map, index);
3610 case BPF_MAP_TYPE_DEVMAP_HASH:
3611 return __dev_map_hash_lookup_elem(map, index);
3612 case BPF_MAP_TYPE_CPUMAP:
3613 return __cpu_map_lookup_elem(map, index);
3614 case BPF_MAP_TYPE_XSKMAP:
3615 return __xsk_map_lookup_elem(map, index);
3616 default:
3617 return NULL;
3618 }
3619 }
3620
bpf_clear_redirect_map(struct bpf_map * map)3621 void bpf_clear_redirect_map(struct bpf_map *map)
3622 {
3623 struct bpf_redirect_info *ri;
3624 int cpu;
3625
3626 for_each_possible_cpu(cpu) {
3627 ri = per_cpu_ptr(&bpf_redirect_info, cpu);
3628 /* Avoid polluting remote cacheline due to writes if
3629 * not needed. Once we pass this test, we need the
3630 * cmpxchg() to make sure it hasn't been changed in
3631 * the meantime by remote CPU.
3632 */
3633 if (unlikely(READ_ONCE(ri->map) == map))
3634 cmpxchg(&ri->map, map, NULL);
3635 }
3636 }
3637
xdp_do_redirect_map(struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog,struct bpf_map * map,struct bpf_redirect_info * ri)3638 static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp,
3639 struct bpf_prog *xdp_prog, struct bpf_map *map,
3640 struct bpf_redirect_info *ri)
3641 {
3642 u32 index = ri->tgt_index;
3643 void *fwd = ri->tgt_value;
3644 int err;
3645
3646 ri->tgt_index = 0;
3647 ri->tgt_value = NULL;
3648 WRITE_ONCE(ri->map, NULL);
3649
3650 if (ri->map_to_flush && unlikely(ri->map_to_flush != map))
3651 xdp_do_flush_map();
3652
3653 err = __bpf_tx_xdp_map(dev, fwd, map, xdp, index);
3654 if (unlikely(err))
3655 goto err;
3656
3657 ri->map_to_flush = map;
3658 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
3659 return 0;
3660 err:
3661 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
3662 return err;
3663 }
3664
xdp_do_redirect(struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)3665 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
3666 struct bpf_prog *xdp_prog)
3667 {
3668 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
3669 struct bpf_map *map = READ_ONCE(ri->map);
3670
3671 if (likely(map))
3672 return xdp_do_redirect_map(dev, xdp, xdp_prog, map, ri);
3673
3674 return xdp_do_redirect_slow(dev, xdp, xdp_prog, ri);
3675 }
3676 EXPORT_SYMBOL_GPL(xdp_do_redirect);
3677
xdp_do_generic_redirect_map(struct net_device * dev,struct sk_buff * skb,struct xdp_buff * xdp,struct bpf_prog * xdp_prog,struct bpf_map * map)3678 static int xdp_do_generic_redirect_map(struct net_device *dev,
3679 struct sk_buff *skb,
3680 struct xdp_buff *xdp,
3681 struct bpf_prog *xdp_prog,
3682 struct bpf_map *map)
3683 {
3684 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
3685 u32 index = ri->tgt_index;
3686 void *fwd = ri->tgt_value;
3687 int err = 0;
3688
3689 ri->tgt_index = 0;
3690 ri->tgt_value = NULL;
3691 WRITE_ONCE(ri->map, NULL);
3692
3693 if (map->map_type == BPF_MAP_TYPE_DEVMAP ||
3694 map->map_type == BPF_MAP_TYPE_DEVMAP_HASH) {
3695 struct bpf_dtab_netdev *dst = fwd;
3696
3697 err = dev_map_generic_redirect(dst, skb, xdp_prog);
3698 if (unlikely(err))
3699 goto err;
3700 } else if (map->map_type == BPF_MAP_TYPE_XSKMAP) {
3701 struct xdp_sock *xs = fwd;
3702
3703 err = xsk_generic_rcv(xs, xdp);
3704 if (err)
3705 goto err;
3706 consume_skb(skb);
3707 } else {
3708 /* TODO: Handle BPF_MAP_TYPE_CPUMAP */
3709 err = -EBADRQC;
3710 goto err;
3711 }
3712
3713 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
3714 return 0;
3715 err:
3716 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
3717 return err;
3718 }
3719
xdp_do_generic_redirect(struct net_device * dev,struct sk_buff * skb,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)3720 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
3721 struct xdp_buff *xdp, struct bpf_prog *xdp_prog)
3722 {
3723 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
3724 struct bpf_map *map = READ_ONCE(ri->map);
3725 u32 index = ri->tgt_index;
3726 struct net_device *fwd;
3727 int err = 0;
3728
3729 if (map)
3730 return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog,
3731 map);
3732 ri->tgt_index = 0;
3733 fwd = dev_get_by_index_rcu(dev_net(dev), index);
3734 if (unlikely(!fwd)) {
3735 err = -EINVAL;
3736 goto err;
3737 }
3738
3739 err = xdp_ok_fwd_dev(fwd, skb->len);
3740 if (unlikely(err))
3741 goto err;
3742
3743 skb->dev = fwd;
3744 _trace_xdp_redirect(dev, xdp_prog, index);
3745 generic_xdp_tx(skb, xdp_prog);
3746 return 0;
3747 err:
3748 _trace_xdp_redirect_err(dev, xdp_prog, index, err);
3749 return err;
3750 }
3751 EXPORT_SYMBOL_GPL(xdp_do_generic_redirect);
3752
BPF_CALL_2(bpf_xdp_redirect,u32,ifindex,u64,flags)3753 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
3754 {
3755 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
3756
3757 if (unlikely(flags))
3758 return XDP_ABORTED;
3759
3760 ri->flags = flags;
3761 ri->tgt_index = ifindex;
3762 ri->tgt_value = NULL;
3763 WRITE_ONCE(ri->map, NULL);
3764
3765 return XDP_REDIRECT;
3766 }
3767
3768 static const struct bpf_func_proto bpf_xdp_redirect_proto = {
3769 .func = bpf_xdp_redirect,
3770 .gpl_only = false,
3771 .ret_type = RET_INTEGER,
3772 .arg1_type = ARG_ANYTHING,
3773 .arg2_type = ARG_ANYTHING,
3774 };
3775
BPF_CALL_3(bpf_xdp_redirect_map,struct bpf_map *,map,u32,ifindex,u64,flags)3776 BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex,
3777 u64, flags)
3778 {
3779 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
3780
3781 /* Lower bits of the flags are used as return code on lookup failure */
3782 if (unlikely(flags > XDP_TX))
3783 return XDP_ABORTED;
3784
3785 ri->tgt_value = __xdp_map_lookup_elem(map, ifindex);
3786 if (unlikely(!ri->tgt_value)) {
3787 /* If the lookup fails we want to clear out the state in the
3788 * redirect_info struct completely, so that if an eBPF program
3789 * performs multiple lookups, the last one always takes
3790 * precedence.
3791 */
3792 WRITE_ONCE(ri->map, NULL);
3793 return flags;
3794 }
3795
3796 ri->flags = flags;
3797 ri->tgt_index = ifindex;
3798 WRITE_ONCE(ri->map, map);
3799
3800 return XDP_REDIRECT;
3801 }
3802
3803 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
3804 .func = bpf_xdp_redirect_map,
3805 .gpl_only = false,
3806 .ret_type = RET_INTEGER,
3807 .arg1_type = ARG_CONST_MAP_PTR,
3808 .arg2_type = ARG_ANYTHING,
3809 .arg3_type = ARG_ANYTHING,
3810 };
3811
bpf_skb_copy(void * dst_buff,const void * skb,unsigned long off,unsigned long len)3812 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
3813 unsigned long off, unsigned long len)
3814 {
3815 void *ptr = skb_header_pointer(skb, off, len, dst_buff);
3816
3817 if (unlikely(!ptr))
3818 return len;
3819 if (ptr != dst_buff)
3820 memcpy(dst_buff, ptr, len);
3821
3822 return 0;
3823 }
3824
BPF_CALL_5(bpf_skb_event_output,struct sk_buff *,skb,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)3825 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
3826 u64, flags, void *, meta, u64, meta_size)
3827 {
3828 u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
3829
3830 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
3831 return -EINVAL;
3832 if (unlikely(skb_size > skb->len))
3833 return -EFAULT;
3834
3835 return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
3836 bpf_skb_copy);
3837 }
3838
3839 static const struct bpf_func_proto bpf_skb_event_output_proto = {
3840 .func = bpf_skb_event_output,
3841 .gpl_only = true,
3842 .ret_type = RET_INTEGER,
3843 .arg1_type = ARG_PTR_TO_CTX,
3844 .arg2_type = ARG_CONST_MAP_PTR,
3845 .arg3_type = ARG_ANYTHING,
3846 .arg4_type = ARG_PTR_TO_MEM,
3847 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
3848 };
3849
bpf_tunnel_key_af(u64 flags)3850 static unsigned short bpf_tunnel_key_af(u64 flags)
3851 {
3852 return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
3853 }
3854
BPF_CALL_4(bpf_skb_get_tunnel_key,struct sk_buff *,skb,struct bpf_tunnel_key *,to,u32,size,u64,flags)3855 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
3856 u32, size, u64, flags)
3857 {
3858 const struct ip_tunnel_info *info = skb_tunnel_info(skb);
3859 u8 compat[sizeof(struct bpf_tunnel_key)];
3860 void *to_orig = to;
3861 int err;
3862
3863 if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) {
3864 err = -EINVAL;
3865 goto err_clear;
3866 }
3867 if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
3868 err = -EPROTO;
3869 goto err_clear;
3870 }
3871 if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
3872 err = -EINVAL;
3873 switch (size) {
3874 case offsetof(struct bpf_tunnel_key, tunnel_label):
3875 case offsetof(struct bpf_tunnel_key, tunnel_ext):
3876 goto set_compat;
3877 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
3878 /* Fixup deprecated structure layouts here, so we have
3879 * a common path later on.
3880 */
3881 if (ip_tunnel_info_af(info) != AF_INET)
3882 goto err_clear;
3883 set_compat:
3884 to = (struct bpf_tunnel_key *)compat;
3885 break;
3886 default:
3887 goto err_clear;
3888 }
3889 }
3890
3891 to->tunnel_id = be64_to_cpu(info->key.tun_id);
3892 to->tunnel_tos = info->key.tos;
3893 to->tunnel_ttl = info->key.ttl;
3894 to->tunnel_ext = 0;
3895
3896 if (flags & BPF_F_TUNINFO_IPV6) {
3897 memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
3898 sizeof(to->remote_ipv6));
3899 to->tunnel_label = be32_to_cpu(info->key.label);
3900 } else {
3901 to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
3902 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
3903 to->tunnel_label = 0;
3904 }
3905
3906 if (unlikely(size != sizeof(struct bpf_tunnel_key)))
3907 memcpy(to_orig, to, size);
3908
3909 return 0;
3910 err_clear:
3911 memset(to_orig, 0, size);
3912 return err;
3913 }
3914
3915 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
3916 .func = bpf_skb_get_tunnel_key,
3917 .gpl_only = false,
3918 .ret_type = RET_INTEGER,
3919 .arg1_type = ARG_PTR_TO_CTX,
3920 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
3921 .arg3_type = ARG_CONST_SIZE,
3922 .arg4_type = ARG_ANYTHING,
3923 };
3924
BPF_CALL_3(bpf_skb_get_tunnel_opt,struct sk_buff *,skb,u8 *,to,u32,size)3925 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
3926 {
3927 const struct ip_tunnel_info *info = skb_tunnel_info(skb);
3928 int err;
3929
3930 if (unlikely(!info ||
3931 !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
3932 err = -ENOENT;
3933 goto err_clear;
3934 }
3935 if (unlikely(size < info->options_len)) {
3936 err = -ENOMEM;
3937 goto err_clear;
3938 }
3939
3940 ip_tunnel_info_opts_get(to, info);
3941 if (size > info->options_len)
3942 memset(to + info->options_len, 0, size - info->options_len);
3943
3944 return info->options_len;
3945 err_clear:
3946 memset(to, 0, size);
3947 return err;
3948 }
3949
3950 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
3951 .func = bpf_skb_get_tunnel_opt,
3952 .gpl_only = false,
3953 .ret_type = RET_INTEGER,
3954 .arg1_type = ARG_PTR_TO_CTX,
3955 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
3956 .arg3_type = ARG_CONST_SIZE,
3957 };
3958
3959 static struct metadata_dst __percpu *md_dst;
3960
BPF_CALL_4(bpf_skb_set_tunnel_key,struct sk_buff *,skb,const struct bpf_tunnel_key *,from,u32,size,u64,flags)3961 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
3962 const struct bpf_tunnel_key *, from, u32, size, u64, flags)
3963 {
3964 struct metadata_dst *md = this_cpu_ptr(md_dst);
3965 u8 compat[sizeof(struct bpf_tunnel_key)];
3966 struct ip_tunnel_info *info;
3967
3968 if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
3969 BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER)))
3970 return -EINVAL;
3971 if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
3972 switch (size) {
3973 case offsetof(struct bpf_tunnel_key, tunnel_label):
3974 case offsetof(struct bpf_tunnel_key, tunnel_ext):
3975 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
3976 /* Fixup deprecated structure layouts here, so we have
3977 * a common path later on.
3978 */
3979 memcpy(compat, from, size);
3980 memset(compat + size, 0, sizeof(compat) - size);
3981 from = (const struct bpf_tunnel_key *) compat;
3982 break;
3983 default:
3984 return -EINVAL;
3985 }
3986 }
3987 if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
3988 from->tunnel_ext))
3989 return -EINVAL;
3990
3991 skb_dst_drop(skb);
3992 dst_hold((struct dst_entry *) md);
3993 skb_dst_set(skb, (struct dst_entry *) md);
3994
3995 info = &md->u.tun_info;
3996 memset(info, 0, sizeof(*info));
3997 info->mode = IP_TUNNEL_INFO_TX;
3998
3999 info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
4000 if (flags & BPF_F_DONT_FRAGMENT)
4001 info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
4002 if (flags & BPF_F_ZERO_CSUM_TX)
4003 info->key.tun_flags &= ~TUNNEL_CSUM;
4004 if (flags & BPF_F_SEQ_NUMBER)
4005 info->key.tun_flags |= TUNNEL_SEQ;
4006
4007 info->key.tun_id = cpu_to_be64(from->tunnel_id);
4008 info->key.tos = from->tunnel_tos;
4009 info->key.ttl = from->tunnel_ttl;
4010
4011 if (flags & BPF_F_TUNINFO_IPV6) {
4012 info->mode |= IP_TUNNEL_INFO_IPV6;
4013 memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
4014 sizeof(from->remote_ipv6));
4015 info->key.label = cpu_to_be32(from->tunnel_label) &
4016 IPV6_FLOWLABEL_MASK;
4017 } else {
4018 info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
4019 }
4020
4021 return 0;
4022 }
4023
4024 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
4025 .func = bpf_skb_set_tunnel_key,
4026 .gpl_only = false,
4027 .ret_type = RET_INTEGER,
4028 .arg1_type = ARG_PTR_TO_CTX,
4029 .arg2_type = ARG_PTR_TO_MEM,
4030 .arg3_type = ARG_CONST_SIZE,
4031 .arg4_type = ARG_ANYTHING,
4032 };
4033
BPF_CALL_3(bpf_skb_set_tunnel_opt,struct sk_buff *,skb,const u8 *,from,u32,size)4034 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
4035 const u8 *, from, u32, size)
4036 {
4037 struct ip_tunnel_info *info = skb_tunnel_info(skb);
4038 const struct metadata_dst *md = this_cpu_ptr(md_dst);
4039
4040 if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
4041 return -EINVAL;
4042 if (unlikely(size > IP_TUNNEL_OPTS_MAX))
4043 return -ENOMEM;
4044
4045 ip_tunnel_info_opts_set(info, from, size, TUNNEL_OPTIONS_PRESENT);
4046
4047 return 0;
4048 }
4049
4050 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
4051 .func = bpf_skb_set_tunnel_opt,
4052 .gpl_only = false,
4053 .ret_type = RET_INTEGER,
4054 .arg1_type = ARG_PTR_TO_CTX,
4055 .arg2_type = ARG_PTR_TO_MEM,
4056 .arg3_type = ARG_CONST_SIZE,
4057 };
4058
4059 static const struct bpf_func_proto *
bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)4060 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
4061 {
4062 if (!md_dst) {
4063 struct metadata_dst __percpu *tmp;
4064
4065 tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
4066 METADATA_IP_TUNNEL,
4067 GFP_KERNEL);
4068 if (!tmp)
4069 return NULL;
4070 if (cmpxchg(&md_dst, NULL, tmp))
4071 metadata_dst_free_percpu(tmp);
4072 }
4073
4074 switch (which) {
4075 case BPF_FUNC_skb_set_tunnel_key:
4076 return &bpf_skb_set_tunnel_key_proto;
4077 case BPF_FUNC_skb_set_tunnel_opt:
4078 return &bpf_skb_set_tunnel_opt_proto;
4079 default:
4080 return NULL;
4081 }
4082 }
4083
BPF_CALL_3(bpf_skb_under_cgroup,struct sk_buff *,skb,struct bpf_map *,map,u32,idx)4084 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
4085 u32, idx)
4086 {
4087 struct bpf_array *array = container_of(map, struct bpf_array, map);
4088 struct cgroup *cgrp;
4089 struct sock *sk;
4090
4091 sk = skb_to_full_sk(skb);
4092 if (!sk || !sk_fullsock(sk))
4093 return -ENOENT;
4094 if (unlikely(idx >= array->map.max_entries))
4095 return -E2BIG;
4096
4097 cgrp = READ_ONCE(array->ptrs[idx]);
4098 if (unlikely(!cgrp))
4099 return -EAGAIN;
4100
4101 return sk_under_cgroup_hierarchy(sk, cgrp);
4102 }
4103
4104 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
4105 .func = bpf_skb_under_cgroup,
4106 .gpl_only = false,
4107 .ret_type = RET_INTEGER,
4108 .arg1_type = ARG_PTR_TO_CTX,
4109 .arg2_type = ARG_CONST_MAP_PTR,
4110 .arg3_type = ARG_ANYTHING,
4111 };
4112
4113 #ifdef CONFIG_SOCK_CGROUP_DATA
BPF_CALL_1(bpf_skb_cgroup_id,const struct sk_buff *,skb)4114 BPF_CALL_1(bpf_skb_cgroup_id, const struct sk_buff *, skb)
4115 {
4116 struct sock *sk = skb_to_full_sk(skb);
4117 struct cgroup *cgrp;
4118
4119 if (!sk || !sk_fullsock(sk))
4120 return 0;
4121
4122 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4123 return cgrp->kn->id.id;
4124 }
4125
4126 static const struct bpf_func_proto bpf_skb_cgroup_id_proto = {
4127 .func = bpf_skb_cgroup_id,
4128 .gpl_only = false,
4129 .ret_type = RET_INTEGER,
4130 .arg1_type = ARG_PTR_TO_CTX,
4131 };
4132
BPF_CALL_2(bpf_skb_ancestor_cgroup_id,const struct sk_buff *,skb,int,ancestor_level)4133 BPF_CALL_2(bpf_skb_ancestor_cgroup_id, const struct sk_buff *, skb, int,
4134 ancestor_level)
4135 {
4136 struct sock *sk = skb_to_full_sk(skb);
4137 struct cgroup *ancestor;
4138 struct cgroup *cgrp;
4139
4140 if (!sk || !sk_fullsock(sk))
4141 return 0;
4142
4143 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4144 ancestor = cgroup_ancestor(cgrp, ancestor_level);
4145 if (!ancestor)
4146 return 0;
4147
4148 return ancestor->kn->id.id;
4149 }
4150
4151 static const struct bpf_func_proto bpf_skb_ancestor_cgroup_id_proto = {
4152 .func = bpf_skb_ancestor_cgroup_id,
4153 .gpl_only = false,
4154 .ret_type = RET_INTEGER,
4155 .arg1_type = ARG_PTR_TO_CTX,
4156 .arg2_type = ARG_ANYTHING,
4157 };
4158 #endif
4159
bpf_xdp_copy(void * dst_buff,const void * src_buff,unsigned long off,unsigned long len)4160 static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff,
4161 unsigned long off, unsigned long len)
4162 {
4163 memcpy(dst_buff, src_buff + off, len);
4164 return 0;
4165 }
4166
BPF_CALL_5(bpf_xdp_event_output,struct xdp_buff *,xdp,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)4167 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
4168 u64, flags, void *, meta, u64, meta_size)
4169 {
4170 u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
4171
4172 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
4173 return -EINVAL;
4174 if (unlikely(xdp_size > (unsigned long)(xdp->data_end - xdp->data)))
4175 return -EFAULT;
4176
4177 return bpf_event_output(map, flags, meta, meta_size, xdp->data,
4178 xdp_size, bpf_xdp_copy);
4179 }
4180
4181 static const struct bpf_func_proto bpf_xdp_event_output_proto = {
4182 .func = bpf_xdp_event_output,
4183 .gpl_only = true,
4184 .ret_type = RET_INTEGER,
4185 .arg1_type = ARG_PTR_TO_CTX,
4186 .arg2_type = ARG_CONST_MAP_PTR,
4187 .arg3_type = ARG_ANYTHING,
4188 .arg4_type = ARG_PTR_TO_MEM,
4189 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
4190 };
4191
BPF_CALL_1(bpf_get_socket_cookie,struct sk_buff *,skb)4192 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
4193 {
4194 return skb->sk ? sock_gen_cookie(skb->sk) : 0;
4195 }
4196
4197 static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
4198 .func = bpf_get_socket_cookie,
4199 .gpl_only = false,
4200 .ret_type = RET_INTEGER,
4201 .arg1_type = ARG_PTR_TO_CTX,
4202 };
4203
BPF_CALL_1(bpf_get_socket_cookie_sock_addr,struct bpf_sock_addr_kern *,ctx)4204 BPF_CALL_1(bpf_get_socket_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
4205 {
4206 return sock_gen_cookie(ctx->sk);
4207 }
4208
4209 static const struct bpf_func_proto bpf_get_socket_cookie_sock_addr_proto = {
4210 .func = bpf_get_socket_cookie_sock_addr,
4211 .gpl_only = false,
4212 .ret_type = RET_INTEGER,
4213 .arg1_type = ARG_PTR_TO_CTX,
4214 };
4215
BPF_CALL_1(bpf_get_socket_cookie_sock_ops,struct bpf_sock_ops_kern *,ctx)4216 BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
4217 {
4218 return sock_gen_cookie(ctx->sk);
4219 }
4220
4221 static const struct bpf_func_proto bpf_get_socket_cookie_sock_ops_proto = {
4222 .func = bpf_get_socket_cookie_sock_ops,
4223 .gpl_only = false,
4224 .ret_type = RET_INTEGER,
4225 .arg1_type = ARG_PTR_TO_CTX,
4226 };
4227
BPF_CALL_1(bpf_get_socket_uid,struct sk_buff *,skb)4228 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
4229 {
4230 struct sock *sk = sk_to_full_sk(skb->sk);
4231 kuid_t kuid;
4232
4233 if (!sk || !sk_fullsock(sk))
4234 return overflowuid;
4235 kuid = sock_net_uid(sock_net(sk), sk);
4236 return from_kuid_munged(sock_net(sk)->user_ns, kuid);
4237 }
4238
4239 static const struct bpf_func_proto bpf_get_socket_uid_proto = {
4240 .func = bpf_get_socket_uid,
4241 .gpl_only = false,
4242 .ret_type = RET_INTEGER,
4243 .arg1_type = ARG_PTR_TO_CTX,
4244 };
4245
BPF_CALL_5(bpf_sockopt_event_output,struct bpf_sock_ops_kern *,bpf_sock,struct bpf_map *,map,u64,flags,void *,data,u64,size)4246 BPF_CALL_5(bpf_sockopt_event_output, struct bpf_sock_ops_kern *, bpf_sock,
4247 struct bpf_map *, map, u64, flags, void *, data, u64, size)
4248 {
4249 if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
4250 return -EINVAL;
4251
4252 return bpf_event_output(map, flags, data, size, NULL, 0, NULL);
4253 }
4254
4255 static const struct bpf_func_proto bpf_sockopt_event_output_proto = {
4256 .func = bpf_sockopt_event_output,
4257 .gpl_only = true,
4258 .ret_type = RET_INTEGER,
4259 .arg1_type = ARG_PTR_TO_CTX,
4260 .arg2_type = ARG_CONST_MAP_PTR,
4261 .arg3_type = ARG_ANYTHING,
4262 .arg4_type = ARG_PTR_TO_MEM,
4263 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
4264 };
4265
BPF_CALL_5(bpf_setsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)4266 BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
4267 int, level, int, optname, char *, optval, int, optlen)
4268 {
4269 struct sock *sk = bpf_sock->sk;
4270 int ret = 0;
4271 int val;
4272
4273 if (!sk_fullsock(sk))
4274 return -EINVAL;
4275
4276 if (level == SOL_SOCKET) {
4277 if (optlen != sizeof(int))
4278 return -EINVAL;
4279 val = *((int *)optval);
4280
4281 /* Only some socketops are supported */
4282 switch (optname) {
4283 case SO_RCVBUF:
4284 val = min_t(u32, val, sysctl_rmem_max);
4285 val = min_t(int, val, INT_MAX / 2);
4286 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
4287 WRITE_ONCE(sk->sk_rcvbuf,
4288 max_t(int, val * 2, SOCK_MIN_RCVBUF));
4289 break;
4290 case SO_SNDBUF:
4291 val = min_t(u32, val, sysctl_wmem_max);
4292 val = min_t(int, val, INT_MAX / 2);
4293 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
4294 WRITE_ONCE(sk->sk_sndbuf,
4295 max_t(int, val * 2, SOCK_MIN_SNDBUF));
4296 break;
4297 case SO_MAX_PACING_RATE: /* 32bit version */
4298 if (val != ~0U)
4299 cmpxchg(&sk->sk_pacing_status,
4300 SK_PACING_NONE,
4301 SK_PACING_NEEDED);
4302 sk->sk_max_pacing_rate = (val == ~0U) ?
4303 ~0UL : (unsigned int)val;
4304 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
4305 sk->sk_max_pacing_rate);
4306 break;
4307 case SO_PRIORITY:
4308 sk->sk_priority = val;
4309 break;
4310 case SO_RCVLOWAT:
4311 if (val < 0)
4312 val = INT_MAX;
4313 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
4314 break;
4315 case SO_MARK:
4316 if (sk->sk_mark != val) {
4317 sk->sk_mark = val;
4318 sk_dst_reset(sk);
4319 }
4320 break;
4321 default:
4322 ret = -EINVAL;
4323 }
4324 #ifdef CONFIG_INET
4325 } else if (level == SOL_IP) {
4326 if (optlen != sizeof(int) || sk->sk_family != AF_INET)
4327 return -EINVAL;
4328
4329 val = *((int *)optval);
4330 /* Only some options are supported */
4331 switch (optname) {
4332 case IP_TOS:
4333 if (val < -1 || val > 0xff) {
4334 ret = -EINVAL;
4335 } else {
4336 struct inet_sock *inet = inet_sk(sk);
4337
4338 if (val == -1)
4339 val = 0;
4340 inet->tos = val;
4341 }
4342 break;
4343 default:
4344 ret = -EINVAL;
4345 }
4346 #if IS_ENABLED(CONFIG_IPV6)
4347 } else if (level == SOL_IPV6) {
4348 if (optlen != sizeof(int) || sk->sk_family != AF_INET6)
4349 return -EINVAL;
4350
4351 val = *((int *)optval);
4352 /* Only some options are supported */
4353 switch (optname) {
4354 case IPV6_TCLASS:
4355 if (val < -1 || val > 0xff) {
4356 ret = -EINVAL;
4357 } else {
4358 struct ipv6_pinfo *np = inet6_sk(sk);
4359
4360 if (val == -1)
4361 val = 0;
4362 np->tclass = val;
4363 }
4364 break;
4365 default:
4366 ret = -EINVAL;
4367 }
4368 #endif
4369 } else if (level == SOL_TCP &&
4370 sk->sk_prot->setsockopt == tcp_setsockopt) {
4371 if (optname == TCP_CONGESTION) {
4372 char name[TCP_CA_NAME_MAX];
4373 bool reinit = bpf_sock->op > BPF_SOCK_OPS_NEEDS_ECN;
4374
4375 strncpy(name, optval, min_t(long, optlen,
4376 TCP_CA_NAME_MAX-1));
4377 name[TCP_CA_NAME_MAX-1] = 0;
4378 ret = tcp_set_congestion_control(sk, name, false,
4379 reinit, true);
4380 } else {
4381 struct tcp_sock *tp = tcp_sk(sk);
4382
4383 if (optlen != sizeof(int))
4384 return -EINVAL;
4385
4386 val = *((int *)optval);
4387 /* Only some options are supported */
4388 switch (optname) {
4389 case TCP_BPF_IW:
4390 if (val <= 0 || tp->data_segs_out > tp->syn_data)
4391 ret = -EINVAL;
4392 else
4393 tp->snd_cwnd = val;
4394 break;
4395 case TCP_BPF_SNDCWND_CLAMP:
4396 if (val <= 0) {
4397 ret = -EINVAL;
4398 } else {
4399 tp->snd_cwnd_clamp = val;
4400 tp->snd_ssthresh = val;
4401 }
4402 break;
4403 case TCP_SAVE_SYN:
4404 if (val < 0 || val > 1)
4405 ret = -EINVAL;
4406 else
4407 tp->save_syn = val;
4408 break;
4409 default:
4410 ret = -EINVAL;
4411 }
4412 }
4413 #endif
4414 } else {
4415 ret = -EINVAL;
4416 }
4417 return ret;
4418 }
4419
4420 static const struct bpf_func_proto bpf_setsockopt_proto = {
4421 .func = bpf_setsockopt,
4422 .gpl_only = false,
4423 .ret_type = RET_INTEGER,
4424 .arg1_type = ARG_PTR_TO_CTX,
4425 .arg2_type = ARG_ANYTHING,
4426 .arg3_type = ARG_ANYTHING,
4427 .arg4_type = ARG_PTR_TO_MEM,
4428 .arg5_type = ARG_CONST_SIZE,
4429 };
4430
BPF_CALL_5(bpf_getsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)4431 BPF_CALL_5(bpf_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
4432 int, level, int, optname, char *, optval, int, optlen)
4433 {
4434 struct sock *sk = bpf_sock->sk;
4435
4436 if (!sk_fullsock(sk))
4437 goto err_clear;
4438 #ifdef CONFIG_INET
4439 if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) {
4440 struct inet_connection_sock *icsk;
4441 struct tcp_sock *tp;
4442
4443 switch (optname) {
4444 case TCP_CONGESTION:
4445 icsk = inet_csk(sk);
4446
4447 if (!icsk->icsk_ca_ops || optlen <= 1)
4448 goto err_clear;
4449 strncpy(optval, icsk->icsk_ca_ops->name, optlen);
4450 optval[optlen - 1] = 0;
4451 break;
4452 case TCP_SAVED_SYN:
4453 tp = tcp_sk(sk);
4454
4455 if (optlen <= 0 || !tp->saved_syn ||
4456 optlen > tp->saved_syn[0])
4457 goto err_clear;
4458 memcpy(optval, tp->saved_syn + 1, optlen);
4459 break;
4460 default:
4461 goto err_clear;
4462 }
4463 } else if (level == SOL_IP) {
4464 struct inet_sock *inet = inet_sk(sk);
4465
4466 if (optlen != sizeof(int) || sk->sk_family != AF_INET)
4467 goto err_clear;
4468
4469 /* Only some options are supported */
4470 switch (optname) {
4471 case IP_TOS:
4472 *((int *)optval) = (int)inet->tos;
4473 break;
4474 default:
4475 goto err_clear;
4476 }
4477 #if IS_ENABLED(CONFIG_IPV6)
4478 } else if (level == SOL_IPV6) {
4479 struct ipv6_pinfo *np = inet6_sk(sk);
4480
4481 if (optlen != sizeof(int) || sk->sk_family != AF_INET6)
4482 goto err_clear;
4483
4484 /* Only some options are supported */
4485 switch (optname) {
4486 case IPV6_TCLASS:
4487 *((int *)optval) = (int)np->tclass;
4488 break;
4489 default:
4490 goto err_clear;
4491 }
4492 #endif
4493 } else {
4494 goto err_clear;
4495 }
4496 return 0;
4497 #endif
4498 err_clear:
4499 memset(optval, 0, optlen);
4500 return -EINVAL;
4501 }
4502
4503 static const struct bpf_func_proto bpf_getsockopt_proto = {
4504 .func = bpf_getsockopt,
4505 .gpl_only = false,
4506 .ret_type = RET_INTEGER,
4507 .arg1_type = ARG_PTR_TO_CTX,
4508 .arg2_type = ARG_ANYTHING,
4509 .arg3_type = ARG_ANYTHING,
4510 .arg4_type = ARG_PTR_TO_UNINIT_MEM,
4511 .arg5_type = ARG_CONST_SIZE,
4512 };
4513
BPF_CALL_2(bpf_sock_ops_cb_flags_set,struct bpf_sock_ops_kern *,bpf_sock,int,argval)4514 BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock,
4515 int, argval)
4516 {
4517 struct sock *sk = bpf_sock->sk;
4518 int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS;
4519
4520 if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk))
4521 return -EINVAL;
4522
4523 tcp_sk(sk)->bpf_sock_ops_cb_flags = val;
4524
4525 return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS);
4526 }
4527
4528 static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = {
4529 .func = bpf_sock_ops_cb_flags_set,
4530 .gpl_only = false,
4531 .ret_type = RET_INTEGER,
4532 .arg1_type = ARG_PTR_TO_CTX,
4533 .arg2_type = ARG_ANYTHING,
4534 };
4535
4536 const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
4537 EXPORT_SYMBOL_GPL(ipv6_bpf_stub);
4538
BPF_CALL_3(bpf_bind,struct bpf_sock_addr_kern *,ctx,struct sockaddr *,addr,int,addr_len)4539 BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr,
4540 int, addr_len)
4541 {
4542 #ifdef CONFIG_INET
4543 struct sock *sk = ctx->sk;
4544 int err;
4545
4546 /* Binding to port can be expensive so it's prohibited in the helper.
4547 * Only binding to IP is supported.
4548 */
4549 err = -EINVAL;
4550 if (addr_len < offsetofend(struct sockaddr, sa_family))
4551 return err;
4552 if (addr->sa_family == AF_INET) {
4553 if (addr_len < sizeof(struct sockaddr_in))
4554 return err;
4555 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
4556 return err;
4557 return __inet_bind(sk, addr, addr_len, true, false);
4558 #if IS_ENABLED(CONFIG_IPV6)
4559 } else if (addr->sa_family == AF_INET6) {
4560 if (addr_len < SIN6_LEN_RFC2133)
4561 return err;
4562 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
4563 return err;
4564 /* ipv6_bpf_stub cannot be NULL, since it's called from
4565 * bpf_cgroup_inet6_connect hook and ipv6 is already loaded
4566 */
4567 return ipv6_bpf_stub->inet6_bind(sk, addr, addr_len, true, false);
4568 #endif /* CONFIG_IPV6 */
4569 }
4570 #endif /* CONFIG_INET */
4571
4572 return -EAFNOSUPPORT;
4573 }
4574
4575 static const struct bpf_func_proto bpf_bind_proto = {
4576 .func = bpf_bind,
4577 .gpl_only = false,
4578 .ret_type = RET_INTEGER,
4579 .arg1_type = ARG_PTR_TO_CTX,
4580 .arg2_type = ARG_PTR_TO_MEM,
4581 .arg3_type = ARG_CONST_SIZE,
4582 };
4583
4584 #ifdef CONFIG_XFRM
BPF_CALL_5(bpf_skb_get_xfrm_state,struct sk_buff *,skb,u32,index,struct bpf_xfrm_state *,to,u32,size,u64,flags)4585 BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index,
4586 struct bpf_xfrm_state *, to, u32, size, u64, flags)
4587 {
4588 const struct sec_path *sp = skb_sec_path(skb);
4589 const struct xfrm_state *x;
4590
4591 if (!sp || unlikely(index >= sp->len || flags))
4592 goto err_clear;
4593
4594 x = sp->xvec[index];
4595
4596 if (unlikely(size != sizeof(struct bpf_xfrm_state)))
4597 goto err_clear;
4598
4599 to->reqid = x->props.reqid;
4600 to->spi = x->id.spi;
4601 to->family = x->props.family;
4602 to->ext = 0;
4603
4604 if (to->family == AF_INET6) {
4605 memcpy(to->remote_ipv6, x->props.saddr.a6,
4606 sizeof(to->remote_ipv6));
4607 } else {
4608 to->remote_ipv4 = x->props.saddr.a4;
4609 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
4610 }
4611
4612 return 0;
4613 err_clear:
4614 memset(to, 0, size);
4615 return -EINVAL;
4616 }
4617
4618 static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = {
4619 .func = bpf_skb_get_xfrm_state,
4620 .gpl_only = false,
4621 .ret_type = RET_INTEGER,
4622 .arg1_type = ARG_PTR_TO_CTX,
4623 .arg2_type = ARG_ANYTHING,
4624 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
4625 .arg4_type = ARG_CONST_SIZE,
4626 .arg5_type = ARG_ANYTHING,
4627 };
4628 #endif
4629
4630 #if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6)
bpf_fib_set_fwd_params(struct bpf_fib_lookup * params,const struct neighbour * neigh,const struct net_device * dev)4631 static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params,
4632 const struct neighbour *neigh,
4633 const struct net_device *dev)
4634 {
4635 memcpy(params->dmac, neigh->ha, ETH_ALEN);
4636 memcpy(params->smac, dev->dev_addr, ETH_ALEN);
4637 params->h_vlan_TCI = 0;
4638 params->h_vlan_proto = 0;
4639
4640 return 0;
4641 }
4642 #endif
4643
4644 #if IS_ENABLED(CONFIG_INET)
bpf_ipv4_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)4645 static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
4646 u32 flags, bool check_mtu)
4647 {
4648 struct fib_nh_common *nhc;
4649 struct in_device *in_dev;
4650 struct neighbour *neigh;
4651 struct net_device *dev;
4652 struct fib_result res;
4653 struct flowi4 fl4;
4654 int err;
4655 u32 mtu;
4656
4657 dev = dev_get_by_index_rcu(net, params->ifindex);
4658 if (unlikely(!dev))
4659 return -ENODEV;
4660
4661 /* verify forwarding is enabled on this interface */
4662 in_dev = __in_dev_get_rcu(dev);
4663 if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev)))
4664 return BPF_FIB_LKUP_RET_FWD_DISABLED;
4665
4666 if (flags & BPF_FIB_LOOKUP_OUTPUT) {
4667 fl4.flowi4_iif = 1;
4668 fl4.flowi4_oif = params->ifindex;
4669 } else {
4670 fl4.flowi4_iif = params->ifindex;
4671 fl4.flowi4_oif = 0;
4672 }
4673 fl4.flowi4_tos = params->tos & IPTOS_RT_MASK;
4674 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
4675 fl4.flowi4_flags = 0;
4676
4677 fl4.flowi4_proto = params->l4_protocol;
4678 fl4.daddr = params->ipv4_dst;
4679 fl4.saddr = params->ipv4_src;
4680 fl4.fl4_sport = params->sport;
4681 fl4.fl4_dport = params->dport;
4682 fl4.flowi4_multipath_hash = 0;
4683
4684 if (flags & BPF_FIB_LOOKUP_DIRECT) {
4685 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
4686 struct fib_table *tb;
4687
4688 tb = fib_get_table(net, tbid);
4689 if (unlikely(!tb))
4690 return BPF_FIB_LKUP_RET_NOT_FWDED;
4691
4692 err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
4693 } else {
4694 fl4.flowi4_mark = 0;
4695 fl4.flowi4_secid = 0;
4696 fl4.flowi4_tun_key.tun_id = 0;
4697 fl4.flowi4_uid = sock_net_uid(net, NULL);
4698
4699 err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF);
4700 }
4701
4702 if (err) {
4703 /* map fib lookup errors to RTN_ type */
4704 if (err == -EINVAL)
4705 return BPF_FIB_LKUP_RET_BLACKHOLE;
4706 if (err == -EHOSTUNREACH)
4707 return BPF_FIB_LKUP_RET_UNREACHABLE;
4708 if (err == -EACCES)
4709 return BPF_FIB_LKUP_RET_PROHIBIT;
4710
4711 return BPF_FIB_LKUP_RET_NOT_FWDED;
4712 }
4713
4714 if (res.type != RTN_UNICAST)
4715 return BPF_FIB_LKUP_RET_NOT_FWDED;
4716
4717 if (fib_info_num_path(res.fi) > 1)
4718 fib_select_path(net, &res, &fl4, NULL);
4719
4720 if (check_mtu) {
4721 mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst);
4722 if (params->tot_len > mtu)
4723 return BPF_FIB_LKUP_RET_FRAG_NEEDED;
4724 }
4725
4726 nhc = res.nhc;
4727
4728 /* do not handle lwt encaps right now */
4729 if (nhc->nhc_lwtstate)
4730 return BPF_FIB_LKUP_RET_UNSUPP_LWT;
4731
4732 dev = nhc->nhc_dev;
4733
4734 params->rt_metric = res.fi->fib_priority;
4735 params->ifindex = dev->ifindex;
4736
4737 /* xdp and cls_bpf programs are run in RCU-bh so
4738 * rcu_read_lock_bh is not needed here
4739 */
4740 if (likely(nhc->nhc_gw_family != AF_INET6)) {
4741 if (nhc->nhc_gw_family)
4742 params->ipv4_dst = nhc->nhc_gw.ipv4;
4743
4744 neigh = __ipv4_neigh_lookup_noref(dev,
4745 (__force u32)params->ipv4_dst);
4746 } else {
4747 struct in6_addr *dst = (struct in6_addr *)params->ipv6_dst;
4748
4749 params->family = AF_INET6;
4750 *dst = nhc->nhc_gw.ipv6;
4751 neigh = __ipv6_neigh_lookup_noref_stub(dev, dst);
4752 }
4753
4754 if (!neigh || !(neigh->nud_state & NUD_VALID))
4755 return BPF_FIB_LKUP_RET_NO_NEIGH;
4756
4757 return bpf_fib_set_fwd_params(params, neigh, dev);
4758 }
4759 #endif
4760
4761 #if IS_ENABLED(CONFIG_IPV6)
bpf_ipv6_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)4762 static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
4763 u32 flags, bool check_mtu)
4764 {
4765 struct in6_addr *src = (struct in6_addr *) params->ipv6_src;
4766 struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst;
4767 struct fib6_result res = {};
4768 struct neighbour *neigh;
4769 struct net_device *dev;
4770 struct inet6_dev *idev;
4771 struct flowi6 fl6;
4772 int strict = 0;
4773 int oif, err;
4774 u32 mtu;
4775
4776 /* link local addresses are never forwarded */
4777 if (rt6_need_strict(dst) || rt6_need_strict(src))
4778 return BPF_FIB_LKUP_RET_NOT_FWDED;
4779
4780 dev = dev_get_by_index_rcu(net, params->ifindex);
4781 if (unlikely(!dev))
4782 return -ENODEV;
4783
4784 idev = __in6_dev_get_safely(dev);
4785 if (unlikely(!idev || !idev->cnf.forwarding))
4786 return BPF_FIB_LKUP_RET_FWD_DISABLED;
4787
4788 if (flags & BPF_FIB_LOOKUP_OUTPUT) {
4789 fl6.flowi6_iif = 1;
4790 oif = fl6.flowi6_oif = params->ifindex;
4791 } else {
4792 oif = fl6.flowi6_iif = params->ifindex;
4793 fl6.flowi6_oif = 0;
4794 strict = RT6_LOOKUP_F_HAS_SADDR;
4795 }
4796 fl6.flowlabel = params->flowinfo;
4797 fl6.flowi6_scope = 0;
4798 fl6.flowi6_flags = 0;
4799 fl6.mp_hash = 0;
4800
4801 fl6.flowi6_proto = params->l4_protocol;
4802 fl6.daddr = *dst;
4803 fl6.saddr = *src;
4804 fl6.fl6_sport = params->sport;
4805 fl6.fl6_dport = params->dport;
4806
4807 if (flags & BPF_FIB_LOOKUP_DIRECT) {
4808 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
4809 struct fib6_table *tb;
4810
4811 tb = ipv6_stub->fib6_get_table(net, tbid);
4812 if (unlikely(!tb))
4813 return BPF_FIB_LKUP_RET_NOT_FWDED;
4814
4815 err = ipv6_stub->fib6_table_lookup(net, tb, oif, &fl6, &res,
4816 strict);
4817 } else {
4818 fl6.flowi6_mark = 0;
4819 fl6.flowi6_secid = 0;
4820 fl6.flowi6_tun_key.tun_id = 0;
4821 fl6.flowi6_uid = sock_net_uid(net, NULL);
4822
4823 err = ipv6_stub->fib6_lookup(net, oif, &fl6, &res, strict);
4824 }
4825
4826 if (unlikely(err || IS_ERR_OR_NULL(res.f6i) ||
4827 res.f6i == net->ipv6.fib6_null_entry))
4828 return BPF_FIB_LKUP_RET_NOT_FWDED;
4829
4830 switch (res.fib6_type) {
4831 /* only unicast is forwarded */
4832 case RTN_UNICAST:
4833 break;
4834 case RTN_BLACKHOLE:
4835 return BPF_FIB_LKUP_RET_BLACKHOLE;
4836 case RTN_UNREACHABLE:
4837 return BPF_FIB_LKUP_RET_UNREACHABLE;
4838 case RTN_PROHIBIT:
4839 return BPF_FIB_LKUP_RET_PROHIBIT;
4840 default:
4841 return BPF_FIB_LKUP_RET_NOT_FWDED;
4842 }
4843
4844 ipv6_stub->fib6_select_path(net, &res, &fl6, fl6.flowi6_oif,
4845 fl6.flowi6_oif != 0, NULL, strict);
4846
4847 if (check_mtu) {
4848 mtu = ipv6_stub->ip6_mtu_from_fib6(&res, dst, src);
4849 if (params->tot_len > mtu)
4850 return BPF_FIB_LKUP_RET_FRAG_NEEDED;
4851 }
4852
4853 if (res.nh->fib_nh_lws)
4854 return BPF_FIB_LKUP_RET_UNSUPP_LWT;
4855
4856 if (res.nh->fib_nh_gw_family)
4857 *dst = res.nh->fib_nh_gw6;
4858
4859 dev = res.nh->fib_nh_dev;
4860 params->rt_metric = res.f6i->fib6_metric;
4861 params->ifindex = dev->ifindex;
4862
4863 /* xdp and cls_bpf programs are run in RCU-bh so rcu_read_lock_bh is
4864 * not needed here.
4865 */
4866 neigh = __ipv6_neigh_lookup_noref_stub(dev, dst);
4867 if (!neigh || !(neigh->nud_state & NUD_VALID))
4868 return BPF_FIB_LKUP_RET_NO_NEIGH;
4869
4870 return bpf_fib_set_fwd_params(params, neigh, dev);
4871 }
4872 #endif
4873
BPF_CALL_4(bpf_xdp_fib_lookup,struct xdp_buff *,ctx,struct bpf_fib_lookup *,params,int,plen,u32,flags)4874 BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx,
4875 struct bpf_fib_lookup *, params, int, plen, u32, flags)
4876 {
4877 if (plen < sizeof(*params))
4878 return -EINVAL;
4879
4880 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT))
4881 return -EINVAL;
4882
4883 switch (params->family) {
4884 #if IS_ENABLED(CONFIG_INET)
4885 case AF_INET:
4886 return bpf_ipv4_fib_lookup(dev_net(ctx->rxq->dev), params,
4887 flags, true);
4888 #endif
4889 #if IS_ENABLED(CONFIG_IPV6)
4890 case AF_INET6:
4891 return bpf_ipv6_fib_lookup(dev_net(ctx->rxq->dev), params,
4892 flags, true);
4893 #endif
4894 }
4895 return -EAFNOSUPPORT;
4896 }
4897
4898 static const struct bpf_func_proto bpf_xdp_fib_lookup_proto = {
4899 .func = bpf_xdp_fib_lookup,
4900 .gpl_only = true,
4901 .ret_type = RET_INTEGER,
4902 .arg1_type = ARG_PTR_TO_CTX,
4903 .arg2_type = ARG_PTR_TO_MEM,
4904 .arg3_type = ARG_CONST_SIZE,
4905 .arg4_type = ARG_ANYTHING,
4906 };
4907
BPF_CALL_4(bpf_skb_fib_lookup,struct sk_buff *,skb,struct bpf_fib_lookup *,params,int,plen,u32,flags)4908 BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
4909 struct bpf_fib_lookup *, params, int, plen, u32, flags)
4910 {
4911 struct net *net = dev_net(skb->dev);
4912 int rc = -EAFNOSUPPORT;
4913 bool check_mtu = false;
4914
4915 if (plen < sizeof(*params))
4916 return -EINVAL;
4917
4918 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT))
4919 return -EINVAL;
4920
4921 if (params->tot_len)
4922 check_mtu = true;
4923
4924 switch (params->family) {
4925 #if IS_ENABLED(CONFIG_INET)
4926 case AF_INET:
4927 rc = bpf_ipv4_fib_lookup(net, params, flags, check_mtu);
4928 break;
4929 #endif
4930 #if IS_ENABLED(CONFIG_IPV6)
4931 case AF_INET6:
4932 rc = bpf_ipv6_fib_lookup(net, params, flags, check_mtu);
4933 break;
4934 #endif
4935 }
4936
4937 if (rc == BPF_FIB_LKUP_RET_SUCCESS && !check_mtu) {
4938 struct net_device *dev;
4939
4940 /* When tot_len isn't provided by user, check skb
4941 * against MTU of FIB lookup resulting net_device
4942 */
4943 dev = dev_get_by_index_rcu(net, params->ifindex);
4944 if (!is_skb_forwardable(dev, skb))
4945 rc = BPF_FIB_LKUP_RET_FRAG_NEEDED;
4946 }
4947
4948 return rc;
4949 }
4950
4951 static const struct bpf_func_proto bpf_skb_fib_lookup_proto = {
4952 .func = bpf_skb_fib_lookup,
4953 .gpl_only = true,
4954 .ret_type = RET_INTEGER,
4955 .arg1_type = ARG_PTR_TO_CTX,
4956 .arg2_type = ARG_PTR_TO_MEM,
4957 .arg3_type = ARG_CONST_SIZE,
4958 .arg4_type = ARG_ANYTHING,
4959 };
4960
4961 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
bpf_push_seg6_encap(struct sk_buff * skb,u32 type,void * hdr,u32 len)4962 static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
4963 {
4964 int err;
4965 struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr;
4966
4967 if (!seg6_validate_srh(srh, len))
4968 return -EINVAL;
4969
4970 switch (type) {
4971 case BPF_LWT_ENCAP_SEG6_INLINE:
4972 if (skb->protocol != htons(ETH_P_IPV6))
4973 return -EBADMSG;
4974
4975 err = seg6_do_srh_inline(skb, srh);
4976 break;
4977 case BPF_LWT_ENCAP_SEG6:
4978 skb_reset_inner_headers(skb);
4979 skb->encapsulation = 1;
4980 err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6);
4981 break;
4982 default:
4983 return -EINVAL;
4984 }
4985
4986 bpf_compute_data_pointers(skb);
4987 if (err)
4988 return err;
4989
4990 skb_set_transport_header(skb, sizeof(struct ipv6hdr));
4991
4992 return seg6_lookup_nexthop(skb, NULL, 0);
4993 }
4994 #endif /* CONFIG_IPV6_SEG6_BPF */
4995
4996 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
bpf_push_ip_encap(struct sk_buff * skb,void * hdr,u32 len,bool ingress)4997 static int bpf_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len,
4998 bool ingress)
4999 {
5000 return bpf_lwt_push_ip_encap(skb, hdr, len, ingress);
5001 }
5002 #endif
5003
BPF_CALL_4(bpf_lwt_in_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)5004 BPF_CALL_4(bpf_lwt_in_push_encap, struct sk_buff *, skb, u32, type, void *, hdr,
5005 u32, len)
5006 {
5007 switch (type) {
5008 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
5009 case BPF_LWT_ENCAP_SEG6:
5010 case BPF_LWT_ENCAP_SEG6_INLINE:
5011 return bpf_push_seg6_encap(skb, type, hdr, len);
5012 #endif
5013 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
5014 case BPF_LWT_ENCAP_IP:
5015 return bpf_push_ip_encap(skb, hdr, len, true /* ingress */);
5016 #endif
5017 default:
5018 return -EINVAL;
5019 }
5020 }
5021
BPF_CALL_4(bpf_lwt_xmit_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)5022 BPF_CALL_4(bpf_lwt_xmit_push_encap, struct sk_buff *, skb, u32, type,
5023 void *, hdr, u32, len)
5024 {
5025 switch (type) {
5026 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
5027 case BPF_LWT_ENCAP_IP:
5028 return bpf_push_ip_encap(skb, hdr, len, false /* egress */);
5029 #endif
5030 default:
5031 return -EINVAL;
5032 }
5033 }
5034
5035 static const struct bpf_func_proto bpf_lwt_in_push_encap_proto = {
5036 .func = bpf_lwt_in_push_encap,
5037 .gpl_only = false,
5038 .ret_type = RET_INTEGER,
5039 .arg1_type = ARG_PTR_TO_CTX,
5040 .arg2_type = ARG_ANYTHING,
5041 .arg3_type = ARG_PTR_TO_MEM,
5042 .arg4_type = ARG_CONST_SIZE
5043 };
5044
5045 static const struct bpf_func_proto bpf_lwt_xmit_push_encap_proto = {
5046 .func = bpf_lwt_xmit_push_encap,
5047 .gpl_only = false,
5048 .ret_type = RET_INTEGER,
5049 .arg1_type = ARG_PTR_TO_CTX,
5050 .arg2_type = ARG_ANYTHING,
5051 .arg3_type = ARG_PTR_TO_MEM,
5052 .arg4_type = ARG_CONST_SIZE
5053 };
5054
5055 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
BPF_CALL_4(bpf_lwt_seg6_store_bytes,struct sk_buff *,skb,u32,offset,const void *,from,u32,len)5056 BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset,
5057 const void *, from, u32, len)
5058 {
5059 struct seg6_bpf_srh_state *srh_state =
5060 this_cpu_ptr(&seg6_bpf_srh_states);
5061 struct ipv6_sr_hdr *srh = srh_state->srh;
5062 void *srh_tlvs, *srh_end, *ptr;
5063 int srhoff = 0;
5064
5065 if (srh == NULL)
5066 return -EINVAL;
5067
5068 srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4));
5069 srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen);
5070
5071 ptr = skb->data + offset;
5072 if (ptr >= srh_tlvs && ptr + len <= srh_end)
5073 srh_state->valid = false;
5074 else if (ptr < (void *)&srh->flags ||
5075 ptr + len > (void *)&srh->segments)
5076 return -EFAULT;
5077
5078 if (unlikely(bpf_try_make_writable(skb, offset + len)))
5079 return -EFAULT;
5080 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
5081 return -EINVAL;
5082 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
5083
5084 memcpy(skb->data + offset, from, len);
5085 return 0;
5086 }
5087
5088 static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = {
5089 .func = bpf_lwt_seg6_store_bytes,
5090 .gpl_only = false,
5091 .ret_type = RET_INTEGER,
5092 .arg1_type = ARG_PTR_TO_CTX,
5093 .arg2_type = ARG_ANYTHING,
5094 .arg3_type = ARG_PTR_TO_MEM,
5095 .arg4_type = ARG_CONST_SIZE
5096 };
5097
bpf_update_srh_state(struct sk_buff * skb)5098 static void bpf_update_srh_state(struct sk_buff *skb)
5099 {
5100 struct seg6_bpf_srh_state *srh_state =
5101 this_cpu_ptr(&seg6_bpf_srh_states);
5102 int srhoff = 0;
5103
5104 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) {
5105 srh_state->srh = NULL;
5106 } else {
5107 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
5108 srh_state->hdrlen = srh_state->srh->hdrlen << 3;
5109 srh_state->valid = true;
5110 }
5111 }
5112
BPF_CALL_4(bpf_lwt_seg6_action,struct sk_buff *,skb,u32,action,void *,param,u32,param_len)5113 BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb,
5114 u32, action, void *, param, u32, param_len)
5115 {
5116 struct seg6_bpf_srh_state *srh_state =
5117 this_cpu_ptr(&seg6_bpf_srh_states);
5118 int hdroff = 0;
5119 int err;
5120
5121 switch (action) {
5122 case SEG6_LOCAL_ACTION_END_X:
5123 if (!seg6_bpf_has_valid_srh(skb))
5124 return -EBADMSG;
5125 if (param_len != sizeof(struct in6_addr))
5126 return -EINVAL;
5127 return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0);
5128 case SEG6_LOCAL_ACTION_END_T:
5129 if (!seg6_bpf_has_valid_srh(skb))
5130 return -EBADMSG;
5131 if (param_len != sizeof(int))
5132 return -EINVAL;
5133 return seg6_lookup_nexthop(skb, NULL, *(int *)param);
5134 case SEG6_LOCAL_ACTION_END_DT6:
5135 if (!seg6_bpf_has_valid_srh(skb))
5136 return -EBADMSG;
5137 if (param_len != sizeof(int))
5138 return -EINVAL;
5139
5140 if (ipv6_find_hdr(skb, &hdroff, IPPROTO_IPV6, NULL, NULL) < 0)
5141 return -EBADMSG;
5142 if (!pskb_pull(skb, hdroff))
5143 return -EBADMSG;
5144
5145 skb_postpull_rcsum(skb, skb_network_header(skb), hdroff);
5146 skb_reset_network_header(skb);
5147 skb_reset_transport_header(skb);
5148 skb->encapsulation = 0;
5149
5150 bpf_compute_data_pointers(skb);
5151 bpf_update_srh_state(skb);
5152 return seg6_lookup_nexthop(skb, NULL, *(int *)param);
5153 case SEG6_LOCAL_ACTION_END_B6:
5154 if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
5155 return -EBADMSG;
5156 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE,
5157 param, param_len);
5158 if (!err)
5159 bpf_update_srh_state(skb);
5160
5161 return err;
5162 case SEG6_LOCAL_ACTION_END_B6_ENCAP:
5163 if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
5164 return -EBADMSG;
5165 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6,
5166 param, param_len);
5167 if (!err)
5168 bpf_update_srh_state(skb);
5169
5170 return err;
5171 default:
5172 return -EINVAL;
5173 }
5174 }
5175
5176 static const struct bpf_func_proto bpf_lwt_seg6_action_proto = {
5177 .func = bpf_lwt_seg6_action,
5178 .gpl_only = false,
5179 .ret_type = RET_INTEGER,
5180 .arg1_type = ARG_PTR_TO_CTX,
5181 .arg2_type = ARG_ANYTHING,
5182 .arg3_type = ARG_PTR_TO_MEM,
5183 .arg4_type = ARG_CONST_SIZE
5184 };
5185
BPF_CALL_3(bpf_lwt_seg6_adjust_srh,struct sk_buff *,skb,u32,offset,s32,len)5186 BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset,
5187 s32, len)
5188 {
5189 struct seg6_bpf_srh_state *srh_state =
5190 this_cpu_ptr(&seg6_bpf_srh_states);
5191 struct ipv6_sr_hdr *srh = srh_state->srh;
5192 void *srh_end, *srh_tlvs, *ptr;
5193 struct ipv6hdr *hdr;
5194 int srhoff = 0;
5195 int ret;
5196
5197 if (unlikely(srh == NULL))
5198 return -EINVAL;
5199
5200 srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) +
5201 ((srh->first_segment + 1) << 4));
5202 srh_end = (void *)((unsigned char *)srh + sizeof(*srh) +
5203 srh_state->hdrlen);
5204 ptr = skb->data + offset;
5205
5206 if (unlikely(ptr < srh_tlvs || ptr > srh_end))
5207 return -EFAULT;
5208 if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end))
5209 return -EFAULT;
5210
5211 if (len > 0) {
5212 ret = skb_cow_head(skb, len);
5213 if (unlikely(ret < 0))
5214 return ret;
5215
5216 ret = bpf_skb_net_hdr_push(skb, offset, len);
5217 } else {
5218 ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len);
5219 }
5220
5221 bpf_compute_data_pointers(skb);
5222 if (unlikely(ret < 0))
5223 return ret;
5224
5225 hdr = (struct ipv6hdr *)skb->data;
5226 hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
5227
5228 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
5229 return -EINVAL;
5230 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
5231 srh_state->hdrlen += len;
5232 srh_state->valid = false;
5233 return 0;
5234 }
5235
5236 static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = {
5237 .func = bpf_lwt_seg6_adjust_srh,
5238 .gpl_only = false,
5239 .ret_type = RET_INTEGER,
5240 .arg1_type = ARG_PTR_TO_CTX,
5241 .arg2_type = ARG_ANYTHING,
5242 .arg3_type = ARG_ANYTHING,
5243 };
5244 #endif /* CONFIG_IPV6_SEG6_BPF */
5245
5246 #ifdef CONFIG_INET
sk_lookup(struct net * net,struct bpf_sock_tuple * tuple,int dif,int sdif,u8 family,u8 proto)5247 static struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple,
5248 int dif, int sdif, u8 family, u8 proto)
5249 {
5250 bool refcounted = false;
5251 struct sock *sk = NULL;
5252
5253 if (family == AF_INET) {
5254 __be32 src4 = tuple->ipv4.saddr;
5255 __be32 dst4 = tuple->ipv4.daddr;
5256
5257 if (proto == IPPROTO_TCP)
5258 sk = __inet_lookup(net, &tcp_hashinfo, NULL, 0,
5259 src4, tuple->ipv4.sport,
5260 dst4, tuple->ipv4.dport,
5261 dif, sdif, &refcounted);
5262 else
5263 sk = __udp4_lib_lookup(net, src4, tuple->ipv4.sport,
5264 dst4, tuple->ipv4.dport,
5265 dif, sdif, &udp_table, NULL);
5266 #if IS_ENABLED(CONFIG_IPV6)
5267 } else {
5268 struct in6_addr *src6 = (struct in6_addr *)&tuple->ipv6.saddr;
5269 struct in6_addr *dst6 = (struct in6_addr *)&tuple->ipv6.daddr;
5270
5271 if (proto == IPPROTO_TCP)
5272 sk = __inet6_lookup(net, &tcp_hashinfo, NULL, 0,
5273 src6, tuple->ipv6.sport,
5274 dst6, ntohs(tuple->ipv6.dport),
5275 dif, sdif, &refcounted);
5276 else if (likely(ipv6_bpf_stub))
5277 sk = ipv6_bpf_stub->udp6_lib_lookup(net,
5278 src6, tuple->ipv6.sport,
5279 dst6, tuple->ipv6.dport,
5280 dif, sdif,
5281 &udp_table, NULL);
5282 #endif
5283 }
5284
5285 if (unlikely(sk && !refcounted && !sock_flag(sk, SOCK_RCU_FREE))) {
5286 WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
5287 sk = NULL;
5288 }
5289 return sk;
5290 }
5291
5292 /* bpf_skc_lookup performs the core lookup for different types of sockets,
5293 * taking a reference on the socket if it doesn't have the flag SOCK_RCU_FREE.
5294 * Returns the socket as an 'unsigned long' to simplify the casting in the
5295 * callers to satisfy BPF_CALL declarations.
5296 */
5297 static struct sock *
__bpf_skc_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,struct net * caller_net,u32 ifindex,u8 proto,u64 netns_id,u64 flags)5298 __bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
5299 struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
5300 u64 flags)
5301 {
5302 struct sock *sk = NULL;
5303 u8 family = AF_UNSPEC;
5304 struct net *net;
5305 int sdif;
5306
5307 if (len == sizeof(tuple->ipv4))
5308 family = AF_INET;
5309 else if (len == sizeof(tuple->ipv6))
5310 family = AF_INET6;
5311 else
5312 return NULL;
5313
5314 if (unlikely(family == AF_UNSPEC || flags ||
5315 !((s32)netns_id < 0 || netns_id <= S32_MAX)))
5316 goto out;
5317
5318 if (family == AF_INET)
5319 sdif = inet_sdif(skb);
5320 else
5321 sdif = inet6_sdif(skb);
5322
5323 if ((s32)netns_id < 0) {
5324 net = caller_net;
5325 sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
5326 } else {
5327 net = get_net_ns_by_id(caller_net, netns_id);
5328 if (unlikely(!net))
5329 goto out;
5330 sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
5331 put_net(net);
5332 }
5333
5334 out:
5335 return sk;
5336 }
5337
5338 static struct sock *
__bpf_sk_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,struct net * caller_net,u32 ifindex,u8 proto,u64 netns_id,u64 flags)5339 __bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
5340 struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
5341 u64 flags)
5342 {
5343 struct sock *sk = __bpf_skc_lookup(skb, tuple, len, caller_net,
5344 ifindex, proto, netns_id, flags);
5345
5346 if (sk) {
5347 struct sock *sk2 = sk_to_full_sk(sk);
5348
5349 /* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
5350 * sock refcnt is decremented to prevent a request_sock leak.
5351 */
5352 if (!sk_fullsock(sk2))
5353 sk2 = NULL;
5354 if (sk2 != sk) {
5355 sock_gen_put(sk);
5356 /* Ensure there is no need to bump sk2 refcnt */
5357 if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
5358 WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
5359 return NULL;
5360 }
5361 sk = sk2;
5362 }
5363 }
5364
5365 return sk;
5366 }
5367
5368 static struct sock *
bpf_skc_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)5369 bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
5370 u8 proto, u64 netns_id, u64 flags)
5371 {
5372 struct net *caller_net;
5373 int ifindex;
5374
5375 if (skb->dev) {
5376 caller_net = dev_net(skb->dev);
5377 ifindex = skb->dev->ifindex;
5378 } else {
5379 caller_net = sock_net(skb->sk);
5380 ifindex = 0;
5381 }
5382
5383 return __bpf_skc_lookup(skb, tuple, len, caller_net, ifindex, proto,
5384 netns_id, flags);
5385 }
5386
5387 static struct sock *
bpf_sk_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)5388 bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
5389 u8 proto, u64 netns_id, u64 flags)
5390 {
5391 struct sock *sk = bpf_skc_lookup(skb, tuple, len, proto, netns_id,
5392 flags);
5393
5394 if (sk) {
5395 struct sock *sk2 = sk_to_full_sk(sk);
5396
5397 /* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
5398 * sock refcnt is decremented to prevent a request_sock leak.
5399 */
5400 if (!sk_fullsock(sk2))
5401 sk2 = NULL;
5402 if (sk2 != sk) {
5403 sock_gen_put(sk);
5404 /* Ensure there is no need to bump sk2 refcnt */
5405 if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
5406 WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
5407 return NULL;
5408 }
5409 sk = sk2;
5410 }
5411 }
5412
5413 return sk;
5414 }
5415
BPF_CALL_5(bpf_skc_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)5416 BPF_CALL_5(bpf_skc_lookup_tcp, struct sk_buff *, skb,
5417 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
5418 {
5419 return (unsigned long)bpf_skc_lookup(skb, tuple, len, IPPROTO_TCP,
5420 netns_id, flags);
5421 }
5422
5423 static const struct bpf_func_proto bpf_skc_lookup_tcp_proto = {
5424 .func = bpf_skc_lookup_tcp,
5425 .gpl_only = false,
5426 .pkt_access = true,
5427 .ret_type = RET_PTR_TO_SOCK_COMMON_OR_NULL,
5428 .arg1_type = ARG_PTR_TO_CTX,
5429 .arg2_type = ARG_PTR_TO_MEM,
5430 .arg3_type = ARG_CONST_SIZE,
5431 .arg4_type = ARG_ANYTHING,
5432 .arg5_type = ARG_ANYTHING,
5433 };
5434
BPF_CALL_5(bpf_sk_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)5435 BPF_CALL_5(bpf_sk_lookup_tcp, struct sk_buff *, skb,
5436 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
5437 {
5438 return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_TCP,
5439 netns_id, flags);
5440 }
5441
5442 static const struct bpf_func_proto bpf_sk_lookup_tcp_proto = {
5443 .func = bpf_sk_lookup_tcp,
5444 .gpl_only = false,
5445 .pkt_access = true,
5446 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
5447 .arg1_type = ARG_PTR_TO_CTX,
5448 .arg2_type = ARG_PTR_TO_MEM,
5449 .arg3_type = ARG_CONST_SIZE,
5450 .arg4_type = ARG_ANYTHING,
5451 .arg5_type = ARG_ANYTHING,
5452 };
5453
BPF_CALL_5(bpf_sk_lookup_udp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)5454 BPF_CALL_5(bpf_sk_lookup_udp, struct sk_buff *, skb,
5455 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
5456 {
5457 return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_UDP,
5458 netns_id, flags);
5459 }
5460
5461 static const struct bpf_func_proto bpf_sk_lookup_udp_proto = {
5462 .func = bpf_sk_lookup_udp,
5463 .gpl_only = false,
5464 .pkt_access = true,
5465 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
5466 .arg1_type = ARG_PTR_TO_CTX,
5467 .arg2_type = ARG_PTR_TO_MEM,
5468 .arg3_type = ARG_CONST_SIZE,
5469 .arg4_type = ARG_ANYTHING,
5470 .arg5_type = ARG_ANYTHING,
5471 };
5472
BPF_CALL_1(bpf_sk_release,struct sock *,sk)5473 BPF_CALL_1(bpf_sk_release, struct sock *, sk)
5474 {
5475 /* Only full sockets have sk->sk_flags. */
5476 if (!sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE))
5477 sock_gen_put(sk);
5478 return 0;
5479 }
5480
5481 static const struct bpf_func_proto bpf_sk_release_proto = {
5482 .func = bpf_sk_release,
5483 .gpl_only = false,
5484 .ret_type = RET_INTEGER,
5485 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
5486 };
5487
BPF_CALL_5(bpf_xdp_sk_lookup_udp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)5488 BPF_CALL_5(bpf_xdp_sk_lookup_udp, struct xdp_buff *, ctx,
5489 struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
5490 {
5491 struct net *caller_net = dev_net(ctx->rxq->dev);
5492 int ifindex = ctx->rxq->dev->ifindex;
5493
5494 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
5495 ifindex, IPPROTO_UDP, netns_id,
5496 flags);
5497 }
5498
5499 static const struct bpf_func_proto bpf_xdp_sk_lookup_udp_proto = {
5500 .func = bpf_xdp_sk_lookup_udp,
5501 .gpl_only = false,
5502 .pkt_access = true,
5503 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
5504 .arg1_type = ARG_PTR_TO_CTX,
5505 .arg2_type = ARG_PTR_TO_MEM,
5506 .arg3_type = ARG_CONST_SIZE,
5507 .arg4_type = ARG_ANYTHING,
5508 .arg5_type = ARG_ANYTHING,
5509 };
5510
BPF_CALL_5(bpf_xdp_skc_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)5511 BPF_CALL_5(bpf_xdp_skc_lookup_tcp, struct xdp_buff *, ctx,
5512 struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
5513 {
5514 struct net *caller_net = dev_net(ctx->rxq->dev);
5515 int ifindex = ctx->rxq->dev->ifindex;
5516
5517 return (unsigned long)__bpf_skc_lookup(NULL, tuple, len, caller_net,
5518 ifindex, IPPROTO_TCP, netns_id,
5519 flags);
5520 }
5521
5522 static const struct bpf_func_proto bpf_xdp_skc_lookup_tcp_proto = {
5523 .func = bpf_xdp_skc_lookup_tcp,
5524 .gpl_only = false,
5525 .pkt_access = true,
5526 .ret_type = RET_PTR_TO_SOCK_COMMON_OR_NULL,
5527 .arg1_type = ARG_PTR_TO_CTX,
5528 .arg2_type = ARG_PTR_TO_MEM,
5529 .arg3_type = ARG_CONST_SIZE,
5530 .arg4_type = ARG_ANYTHING,
5531 .arg5_type = ARG_ANYTHING,
5532 };
5533
BPF_CALL_5(bpf_xdp_sk_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)5534 BPF_CALL_5(bpf_xdp_sk_lookup_tcp, struct xdp_buff *, ctx,
5535 struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
5536 {
5537 struct net *caller_net = dev_net(ctx->rxq->dev);
5538 int ifindex = ctx->rxq->dev->ifindex;
5539
5540 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
5541 ifindex, IPPROTO_TCP, netns_id,
5542 flags);
5543 }
5544
5545 static const struct bpf_func_proto bpf_xdp_sk_lookup_tcp_proto = {
5546 .func = bpf_xdp_sk_lookup_tcp,
5547 .gpl_only = false,
5548 .pkt_access = true,
5549 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
5550 .arg1_type = ARG_PTR_TO_CTX,
5551 .arg2_type = ARG_PTR_TO_MEM,
5552 .arg3_type = ARG_CONST_SIZE,
5553 .arg4_type = ARG_ANYTHING,
5554 .arg5_type = ARG_ANYTHING,
5555 };
5556
BPF_CALL_5(bpf_sock_addr_skc_lookup_tcp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)5557 BPF_CALL_5(bpf_sock_addr_skc_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
5558 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
5559 {
5560 return (unsigned long)__bpf_skc_lookup(NULL, tuple, len,
5561 sock_net(ctx->sk), 0,
5562 IPPROTO_TCP, netns_id, flags);
5563 }
5564
5565 static const struct bpf_func_proto bpf_sock_addr_skc_lookup_tcp_proto = {
5566 .func = bpf_sock_addr_skc_lookup_tcp,
5567 .gpl_only = false,
5568 .ret_type = RET_PTR_TO_SOCK_COMMON_OR_NULL,
5569 .arg1_type = ARG_PTR_TO_CTX,
5570 .arg2_type = ARG_PTR_TO_MEM,
5571 .arg3_type = ARG_CONST_SIZE,
5572 .arg4_type = ARG_ANYTHING,
5573 .arg5_type = ARG_ANYTHING,
5574 };
5575
BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)5576 BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
5577 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
5578 {
5579 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
5580 sock_net(ctx->sk), 0, IPPROTO_TCP,
5581 netns_id, flags);
5582 }
5583
5584 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_tcp_proto = {
5585 .func = bpf_sock_addr_sk_lookup_tcp,
5586 .gpl_only = false,
5587 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
5588 .arg1_type = ARG_PTR_TO_CTX,
5589 .arg2_type = ARG_PTR_TO_MEM,
5590 .arg3_type = ARG_CONST_SIZE,
5591 .arg4_type = ARG_ANYTHING,
5592 .arg5_type = ARG_ANYTHING,
5593 };
5594
BPF_CALL_5(bpf_sock_addr_sk_lookup_udp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)5595 BPF_CALL_5(bpf_sock_addr_sk_lookup_udp, struct bpf_sock_addr_kern *, ctx,
5596 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
5597 {
5598 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
5599 sock_net(ctx->sk), 0, IPPROTO_UDP,
5600 netns_id, flags);
5601 }
5602
5603 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_udp_proto = {
5604 .func = bpf_sock_addr_sk_lookup_udp,
5605 .gpl_only = false,
5606 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
5607 .arg1_type = ARG_PTR_TO_CTX,
5608 .arg2_type = ARG_PTR_TO_MEM,
5609 .arg3_type = ARG_CONST_SIZE,
5610 .arg4_type = ARG_ANYTHING,
5611 .arg5_type = ARG_ANYTHING,
5612 };
5613
bpf_tcp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)5614 bool bpf_tcp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
5615 struct bpf_insn_access_aux *info)
5616 {
5617 if (off < 0 || off >= offsetofend(struct bpf_tcp_sock,
5618 icsk_retransmits))
5619 return false;
5620
5621 if (off % size != 0)
5622 return false;
5623
5624 switch (off) {
5625 case offsetof(struct bpf_tcp_sock, bytes_received):
5626 case offsetof(struct bpf_tcp_sock, bytes_acked):
5627 return size == sizeof(__u64);
5628 default:
5629 return size == sizeof(__u32);
5630 }
5631 }
5632
bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)5633 u32 bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,
5634 const struct bpf_insn *si,
5635 struct bpf_insn *insn_buf,
5636 struct bpf_prog *prog, u32 *target_size)
5637 {
5638 struct bpf_insn *insn = insn_buf;
5639
5640 #define BPF_TCP_SOCK_GET_COMMON(FIELD) \
5641 do { \
5642 BUILD_BUG_ON(FIELD_SIZEOF(struct tcp_sock, FIELD) > \
5643 FIELD_SIZEOF(struct bpf_tcp_sock, FIELD)); \
5644 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_sock, FIELD),\
5645 si->dst_reg, si->src_reg, \
5646 offsetof(struct tcp_sock, FIELD)); \
5647 } while (0)
5648
5649 #define BPF_INET_SOCK_GET_COMMON(FIELD) \
5650 do { \
5651 BUILD_BUG_ON(FIELD_SIZEOF(struct inet_connection_sock, \
5652 FIELD) > \
5653 FIELD_SIZEOF(struct bpf_tcp_sock, FIELD)); \
5654 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
5655 struct inet_connection_sock, \
5656 FIELD), \
5657 si->dst_reg, si->src_reg, \
5658 offsetof( \
5659 struct inet_connection_sock, \
5660 FIELD)); \
5661 } while (0)
5662
5663 if (insn > insn_buf)
5664 return insn - insn_buf;
5665
5666 switch (si->off) {
5667 case offsetof(struct bpf_tcp_sock, rtt_min):
5668 BUILD_BUG_ON(FIELD_SIZEOF(struct tcp_sock, rtt_min) !=
5669 sizeof(struct minmax));
5670 BUILD_BUG_ON(sizeof(struct minmax) <
5671 sizeof(struct minmax_sample));
5672
5673 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
5674 offsetof(struct tcp_sock, rtt_min) +
5675 offsetof(struct minmax_sample, v));
5676 break;
5677 case offsetof(struct bpf_tcp_sock, snd_cwnd):
5678 BPF_TCP_SOCK_GET_COMMON(snd_cwnd);
5679 break;
5680 case offsetof(struct bpf_tcp_sock, srtt_us):
5681 BPF_TCP_SOCK_GET_COMMON(srtt_us);
5682 break;
5683 case offsetof(struct bpf_tcp_sock, snd_ssthresh):
5684 BPF_TCP_SOCK_GET_COMMON(snd_ssthresh);
5685 break;
5686 case offsetof(struct bpf_tcp_sock, rcv_nxt):
5687 BPF_TCP_SOCK_GET_COMMON(rcv_nxt);
5688 break;
5689 case offsetof(struct bpf_tcp_sock, snd_nxt):
5690 BPF_TCP_SOCK_GET_COMMON(snd_nxt);
5691 break;
5692 case offsetof(struct bpf_tcp_sock, snd_una):
5693 BPF_TCP_SOCK_GET_COMMON(snd_una);
5694 break;
5695 case offsetof(struct bpf_tcp_sock, mss_cache):
5696 BPF_TCP_SOCK_GET_COMMON(mss_cache);
5697 break;
5698 case offsetof(struct bpf_tcp_sock, ecn_flags):
5699 BPF_TCP_SOCK_GET_COMMON(ecn_flags);
5700 break;
5701 case offsetof(struct bpf_tcp_sock, rate_delivered):
5702 BPF_TCP_SOCK_GET_COMMON(rate_delivered);
5703 break;
5704 case offsetof(struct bpf_tcp_sock, rate_interval_us):
5705 BPF_TCP_SOCK_GET_COMMON(rate_interval_us);
5706 break;
5707 case offsetof(struct bpf_tcp_sock, packets_out):
5708 BPF_TCP_SOCK_GET_COMMON(packets_out);
5709 break;
5710 case offsetof(struct bpf_tcp_sock, retrans_out):
5711 BPF_TCP_SOCK_GET_COMMON(retrans_out);
5712 break;
5713 case offsetof(struct bpf_tcp_sock, total_retrans):
5714 BPF_TCP_SOCK_GET_COMMON(total_retrans);
5715 break;
5716 case offsetof(struct bpf_tcp_sock, segs_in):
5717 BPF_TCP_SOCK_GET_COMMON(segs_in);
5718 break;
5719 case offsetof(struct bpf_tcp_sock, data_segs_in):
5720 BPF_TCP_SOCK_GET_COMMON(data_segs_in);
5721 break;
5722 case offsetof(struct bpf_tcp_sock, segs_out):
5723 BPF_TCP_SOCK_GET_COMMON(segs_out);
5724 break;
5725 case offsetof(struct bpf_tcp_sock, data_segs_out):
5726 BPF_TCP_SOCK_GET_COMMON(data_segs_out);
5727 break;
5728 case offsetof(struct bpf_tcp_sock, lost_out):
5729 BPF_TCP_SOCK_GET_COMMON(lost_out);
5730 break;
5731 case offsetof(struct bpf_tcp_sock, sacked_out):
5732 BPF_TCP_SOCK_GET_COMMON(sacked_out);
5733 break;
5734 case offsetof(struct bpf_tcp_sock, bytes_received):
5735 BPF_TCP_SOCK_GET_COMMON(bytes_received);
5736 break;
5737 case offsetof(struct bpf_tcp_sock, bytes_acked):
5738 BPF_TCP_SOCK_GET_COMMON(bytes_acked);
5739 break;
5740 case offsetof(struct bpf_tcp_sock, dsack_dups):
5741 BPF_TCP_SOCK_GET_COMMON(dsack_dups);
5742 break;
5743 case offsetof(struct bpf_tcp_sock, delivered):
5744 BPF_TCP_SOCK_GET_COMMON(delivered);
5745 break;
5746 case offsetof(struct bpf_tcp_sock, delivered_ce):
5747 BPF_TCP_SOCK_GET_COMMON(delivered_ce);
5748 break;
5749 case offsetof(struct bpf_tcp_sock, icsk_retransmits):
5750 BPF_INET_SOCK_GET_COMMON(icsk_retransmits);
5751 break;
5752 }
5753
5754 return insn - insn_buf;
5755 }
5756
BPF_CALL_1(bpf_tcp_sock,struct sock *,sk)5757 BPF_CALL_1(bpf_tcp_sock, struct sock *, sk)
5758 {
5759 if (sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP)
5760 return (unsigned long)sk;
5761
5762 return (unsigned long)NULL;
5763 }
5764
5765 const struct bpf_func_proto bpf_tcp_sock_proto = {
5766 .func = bpf_tcp_sock,
5767 .gpl_only = false,
5768 .ret_type = RET_PTR_TO_TCP_SOCK_OR_NULL,
5769 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
5770 };
5771
BPF_CALL_1(bpf_get_listener_sock,struct sock *,sk)5772 BPF_CALL_1(bpf_get_listener_sock, struct sock *, sk)
5773 {
5774 sk = sk_to_full_sk(sk);
5775
5776 if (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_RCU_FREE))
5777 return (unsigned long)sk;
5778
5779 return (unsigned long)NULL;
5780 }
5781
5782 static const struct bpf_func_proto bpf_get_listener_sock_proto = {
5783 .func = bpf_get_listener_sock,
5784 .gpl_only = false,
5785 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
5786 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
5787 };
5788
BPF_CALL_1(bpf_skb_ecn_set_ce,struct sk_buff *,skb)5789 BPF_CALL_1(bpf_skb_ecn_set_ce, struct sk_buff *, skb)
5790 {
5791 unsigned int iphdr_len;
5792
5793 switch (skb_protocol(skb, true)) {
5794 case cpu_to_be16(ETH_P_IP):
5795 iphdr_len = sizeof(struct iphdr);
5796 break;
5797 case cpu_to_be16(ETH_P_IPV6):
5798 iphdr_len = sizeof(struct ipv6hdr);
5799 break;
5800 default:
5801 return 0;
5802 }
5803
5804 if (skb_headlen(skb) < iphdr_len)
5805 return 0;
5806
5807 if (skb_cloned(skb) && !skb_clone_writable(skb, iphdr_len))
5808 return 0;
5809
5810 return INET_ECN_set_ce(skb);
5811 }
5812
bpf_xdp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)5813 bool bpf_xdp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
5814 struct bpf_insn_access_aux *info)
5815 {
5816 if (off < 0 || off >= offsetofend(struct bpf_xdp_sock, queue_id))
5817 return false;
5818
5819 if (off % size != 0)
5820 return false;
5821
5822 switch (off) {
5823 default:
5824 return size == sizeof(__u32);
5825 }
5826 }
5827
bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)5828 u32 bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,
5829 const struct bpf_insn *si,
5830 struct bpf_insn *insn_buf,
5831 struct bpf_prog *prog, u32 *target_size)
5832 {
5833 struct bpf_insn *insn = insn_buf;
5834
5835 #define BPF_XDP_SOCK_GET(FIELD) \
5836 do { \
5837 BUILD_BUG_ON(FIELD_SIZEOF(struct xdp_sock, FIELD) > \
5838 FIELD_SIZEOF(struct bpf_xdp_sock, FIELD)); \
5839 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_sock, FIELD),\
5840 si->dst_reg, si->src_reg, \
5841 offsetof(struct xdp_sock, FIELD)); \
5842 } while (0)
5843
5844 switch (si->off) {
5845 case offsetof(struct bpf_xdp_sock, queue_id):
5846 BPF_XDP_SOCK_GET(queue_id);
5847 break;
5848 }
5849
5850 return insn - insn_buf;
5851 }
5852
5853 static const struct bpf_func_proto bpf_skb_ecn_set_ce_proto = {
5854 .func = bpf_skb_ecn_set_ce,
5855 .gpl_only = false,
5856 .ret_type = RET_INTEGER,
5857 .arg1_type = ARG_PTR_TO_CTX,
5858 };
5859
BPF_CALL_5(bpf_tcp_check_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)5860 BPF_CALL_5(bpf_tcp_check_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
5861 struct tcphdr *, th, u32, th_len)
5862 {
5863 #ifdef CONFIG_SYN_COOKIES
5864 u32 cookie;
5865 int ret;
5866
5867 if (unlikely(th_len < sizeof(*th)))
5868 return -EINVAL;
5869
5870 /* sk_listener() allows TCP_NEW_SYN_RECV, which makes no sense here. */
5871 if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
5872 return -EINVAL;
5873
5874 if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
5875 return -EINVAL;
5876
5877 if (!th->ack || th->rst || th->syn)
5878 return -ENOENT;
5879
5880 if (unlikely(iph_len < sizeof(struct iphdr)))
5881 return -EINVAL;
5882
5883 if (tcp_synq_no_recent_overflow(sk))
5884 return -ENOENT;
5885
5886 cookie = ntohl(th->ack_seq) - 1;
5887
5888 /* Both struct iphdr and struct ipv6hdr have the version field at the
5889 * same offset so we can cast to the shorter header (struct iphdr).
5890 */
5891 switch (((struct iphdr *)iph)->version) {
5892 case 4:
5893 if (sk->sk_family == AF_INET6 && ipv6_only_sock(sk))
5894 return -EINVAL;
5895
5896 ret = __cookie_v4_check((struct iphdr *)iph, th, cookie);
5897 break;
5898
5899 #if IS_BUILTIN(CONFIG_IPV6)
5900 case 6:
5901 if (unlikely(iph_len < sizeof(struct ipv6hdr)))
5902 return -EINVAL;
5903
5904 if (sk->sk_family != AF_INET6)
5905 return -EINVAL;
5906
5907 ret = __cookie_v6_check((struct ipv6hdr *)iph, th, cookie);
5908 break;
5909 #endif /* CONFIG_IPV6 */
5910
5911 default:
5912 return -EPROTONOSUPPORT;
5913 }
5914
5915 if (ret > 0)
5916 return 0;
5917
5918 return -ENOENT;
5919 #else
5920 return -ENOTSUPP;
5921 #endif
5922 }
5923
5924 static const struct bpf_func_proto bpf_tcp_check_syncookie_proto = {
5925 .func = bpf_tcp_check_syncookie,
5926 .gpl_only = true,
5927 .pkt_access = true,
5928 .ret_type = RET_INTEGER,
5929 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
5930 .arg2_type = ARG_PTR_TO_MEM,
5931 .arg3_type = ARG_CONST_SIZE,
5932 .arg4_type = ARG_PTR_TO_MEM,
5933 .arg5_type = ARG_CONST_SIZE,
5934 };
5935
BPF_CALL_5(bpf_tcp_gen_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)5936 BPF_CALL_5(bpf_tcp_gen_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
5937 struct tcphdr *, th, u32, th_len)
5938 {
5939 #ifdef CONFIG_SYN_COOKIES
5940 u32 cookie;
5941 u16 mss;
5942
5943 if (unlikely(th_len < sizeof(*th) || th_len != th->doff * 4))
5944 return -EINVAL;
5945
5946 if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
5947 return -EINVAL;
5948
5949 if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
5950 return -ENOENT;
5951
5952 if (!th->syn || th->ack || th->fin || th->rst)
5953 return -EINVAL;
5954
5955 if (unlikely(iph_len < sizeof(struct iphdr)))
5956 return -EINVAL;
5957
5958 /* Both struct iphdr and struct ipv6hdr have the version field at the
5959 * same offset so we can cast to the shorter header (struct iphdr).
5960 */
5961 switch (((struct iphdr *)iph)->version) {
5962 case 4:
5963 if (sk->sk_family == AF_INET6 && sk->sk_ipv6only)
5964 return -EINVAL;
5965
5966 mss = tcp_v4_get_syncookie(sk, iph, th, &cookie);
5967 break;
5968
5969 #if IS_BUILTIN(CONFIG_IPV6)
5970 case 6:
5971 if (unlikely(iph_len < sizeof(struct ipv6hdr)))
5972 return -EINVAL;
5973
5974 if (sk->sk_family != AF_INET6)
5975 return -EINVAL;
5976
5977 mss = tcp_v6_get_syncookie(sk, iph, th, &cookie);
5978 break;
5979 #endif /* CONFIG_IPV6 */
5980
5981 default:
5982 return -EPROTONOSUPPORT;
5983 }
5984 if (mss == 0)
5985 return -ENOENT;
5986
5987 return cookie | ((u64)mss << 32);
5988 #else
5989 return -EOPNOTSUPP;
5990 #endif /* CONFIG_SYN_COOKIES */
5991 }
5992
5993 static const struct bpf_func_proto bpf_tcp_gen_syncookie_proto = {
5994 .func = bpf_tcp_gen_syncookie,
5995 .gpl_only = true, /* __cookie_v*_init_sequence() is GPL */
5996 .pkt_access = true,
5997 .ret_type = RET_INTEGER,
5998 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
5999 .arg2_type = ARG_PTR_TO_MEM,
6000 .arg3_type = ARG_CONST_SIZE,
6001 .arg4_type = ARG_PTR_TO_MEM,
6002 .arg5_type = ARG_CONST_SIZE,
6003 };
6004
6005 #endif /* CONFIG_INET */
6006
bpf_helper_changes_pkt_data(void * func)6007 bool bpf_helper_changes_pkt_data(void *func)
6008 {
6009 if (func == bpf_skb_vlan_push ||
6010 func == bpf_skb_vlan_pop ||
6011 func == bpf_skb_store_bytes ||
6012 func == bpf_skb_change_proto ||
6013 func == bpf_skb_change_head ||
6014 func == sk_skb_change_head ||
6015 func == bpf_skb_change_tail ||
6016 func == sk_skb_change_tail ||
6017 func == bpf_skb_adjust_room ||
6018 func == bpf_skb_pull_data ||
6019 func == sk_skb_pull_data ||
6020 func == bpf_clone_redirect ||
6021 func == bpf_l3_csum_replace ||
6022 func == bpf_l4_csum_replace ||
6023 func == bpf_xdp_adjust_head ||
6024 func == bpf_xdp_adjust_meta ||
6025 func == bpf_msg_pull_data ||
6026 func == bpf_msg_push_data ||
6027 func == bpf_msg_pop_data ||
6028 func == bpf_xdp_adjust_tail ||
6029 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
6030 func == bpf_lwt_seg6_store_bytes ||
6031 func == bpf_lwt_seg6_adjust_srh ||
6032 func == bpf_lwt_seg6_action ||
6033 #endif
6034 func == bpf_lwt_in_push_encap ||
6035 func == bpf_lwt_xmit_push_encap)
6036 return true;
6037
6038 return false;
6039 }
6040
6041 static const struct bpf_func_proto *
bpf_base_func_proto(enum bpf_func_id func_id)6042 bpf_base_func_proto(enum bpf_func_id func_id)
6043 {
6044 switch (func_id) {
6045 case BPF_FUNC_map_lookup_elem:
6046 return &bpf_map_lookup_elem_proto;
6047 case BPF_FUNC_map_update_elem:
6048 return &bpf_map_update_elem_proto;
6049 case BPF_FUNC_map_delete_elem:
6050 return &bpf_map_delete_elem_proto;
6051 case BPF_FUNC_map_push_elem:
6052 return &bpf_map_push_elem_proto;
6053 case BPF_FUNC_map_pop_elem:
6054 return &bpf_map_pop_elem_proto;
6055 case BPF_FUNC_map_peek_elem:
6056 return &bpf_map_peek_elem_proto;
6057 case BPF_FUNC_get_prandom_u32:
6058 return &bpf_get_prandom_u32_proto;
6059 case BPF_FUNC_get_smp_processor_id:
6060 return &bpf_get_raw_smp_processor_id_proto;
6061 case BPF_FUNC_get_numa_node_id:
6062 return &bpf_get_numa_node_id_proto;
6063 case BPF_FUNC_tail_call:
6064 return &bpf_tail_call_proto;
6065 case BPF_FUNC_ktime_get_ns:
6066 return &bpf_ktime_get_ns_proto;
6067 case BPF_FUNC_ktime_get_boot_ns:
6068 return &bpf_ktime_get_boot_ns_proto;
6069 default:
6070 break;
6071 }
6072
6073 if (!capable(CAP_SYS_ADMIN))
6074 return NULL;
6075
6076 switch (func_id) {
6077 case BPF_FUNC_spin_lock:
6078 return &bpf_spin_lock_proto;
6079 case BPF_FUNC_spin_unlock:
6080 return &bpf_spin_unlock_proto;
6081 case BPF_FUNC_trace_printk:
6082 return bpf_get_trace_printk_proto();
6083 default:
6084 return NULL;
6085 }
6086 }
6087
6088 static const struct bpf_func_proto *
sock_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6089 sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6090 {
6091 switch (func_id) {
6092 /* inet and inet6 sockets are created in a process
6093 * context so there is always a valid uid/gid
6094 */
6095 case BPF_FUNC_get_current_uid_gid:
6096 return &bpf_get_current_uid_gid_proto;
6097 case BPF_FUNC_get_local_storage:
6098 return &bpf_get_local_storage_proto;
6099 default:
6100 return bpf_base_func_proto(func_id);
6101 }
6102 }
6103
6104 static const struct bpf_func_proto *
sock_addr_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6105 sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6106 {
6107 switch (func_id) {
6108 /* inet and inet6 sockets are created in a process
6109 * context so there is always a valid uid/gid
6110 */
6111 case BPF_FUNC_get_current_uid_gid:
6112 return &bpf_get_current_uid_gid_proto;
6113 case BPF_FUNC_bind:
6114 switch (prog->expected_attach_type) {
6115 case BPF_CGROUP_INET4_CONNECT:
6116 case BPF_CGROUP_INET6_CONNECT:
6117 return &bpf_bind_proto;
6118 default:
6119 return NULL;
6120 }
6121 case BPF_FUNC_get_socket_cookie:
6122 return &bpf_get_socket_cookie_sock_addr_proto;
6123 case BPF_FUNC_get_local_storage:
6124 return &bpf_get_local_storage_proto;
6125 #ifdef CONFIG_INET
6126 case BPF_FUNC_sk_lookup_tcp:
6127 return &bpf_sock_addr_sk_lookup_tcp_proto;
6128 case BPF_FUNC_sk_lookup_udp:
6129 return &bpf_sock_addr_sk_lookup_udp_proto;
6130 case BPF_FUNC_sk_release:
6131 return &bpf_sk_release_proto;
6132 case BPF_FUNC_skc_lookup_tcp:
6133 return &bpf_sock_addr_skc_lookup_tcp_proto;
6134 #endif /* CONFIG_INET */
6135 case BPF_FUNC_sk_storage_get:
6136 return &bpf_sk_storage_get_proto;
6137 case BPF_FUNC_sk_storage_delete:
6138 return &bpf_sk_storage_delete_proto;
6139 default:
6140 return bpf_base_func_proto(func_id);
6141 }
6142 }
6143
6144 static const struct bpf_func_proto *
sk_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6145 sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6146 {
6147 switch (func_id) {
6148 case BPF_FUNC_skb_load_bytes:
6149 return &bpf_skb_load_bytes_proto;
6150 case BPF_FUNC_skb_load_bytes_relative:
6151 return &bpf_skb_load_bytes_relative_proto;
6152 case BPF_FUNC_get_socket_cookie:
6153 return &bpf_get_socket_cookie_proto;
6154 case BPF_FUNC_get_socket_uid:
6155 return &bpf_get_socket_uid_proto;
6156 case BPF_FUNC_perf_event_output:
6157 return &bpf_skb_event_output_proto;
6158 default:
6159 return bpf_base_func_proto(func_id);
6160 }
6161 }
6162
6163 const struct bpf_func_proto bpf_sk_storage_get_proto __weak;
6164 const struct bpf_func_proto bpf_sk_storage_delete_proto __weak;
6165
6166 static const struct bpf_func_proto *
cg_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6167 cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6168 {
6169 switch (func_id) {
6170 case BPF_FUNC_get_local_storage:
6171 return &bpf_get_local_storage_proto;
6172 case BPF_FUNC_sk_fullsock:
6173 return &bpf_sk_fullsock_proto;
6174 case BPF_FUNC_sk_storage_get:
6175 return &bpf_sk_storage_get_proto;
6176 case BPF_FUNC_sk_storage_delete:
6177 return &bpf_sk_storage_delete_proto;
6178 case BPF_FUNC_perf_event_output:
6179 return &bpf_skb_event_output_proto;
6180 #ifdef CONFIG_SOCK_CGROUP_DATA
6181 case BPF_FUNC_skb_cgroup_id:
6182 return &bpf_skb_cgroup_id_proto;
6183 #endif
6184 #ifdef CONFIG_INET
6185 case BPF_FUNC_tcp_sock:
6186 return &bpf_tcp_sock_proto;
6187 case BPF_FUNC_get_listener_sock:
6188 return &bpf_get_listener_sock_proto;
6189 case BPF_FUNC_skb_ecn_set_ce:
6190 return &bpf_skb_ecn_set_ce_proto;
6191 #endif
6192 default:
6193 return sk_filter_func_proto(func_id, prog);
6194 }
6195 }
6196
6197 static const struct bpf_func_proto *
tc_cls_act_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6198 tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6199 {
6200 switch (func_id) {
6201 case BPF_FUNC_skb_store_bytes:
6202 return &bpf_skb_store_bytes_proto;
6203 case BPF_FUNC_skb_load_bytes:
6204 return &bpf_skb_load_bytes_proto;
6205 case BPF_FUNC_skb_load_bytes_relative:
6206 return &bpf_skb_load_bytes_relative_proto;
6207 case BPF_FUNC_skb_pull_data:
6208 return &bpf_skb_pull_data_proto;
6209 case BPF_FUNC_csum_diff:
6210 return &bpf_csum_diff_proto;
6211 case BPF_FUNC_csum_update:
6212 return &bpf_csum_update_proto;
6213 case BPF_FUNC_l3_csum_replace:
6214 return &bpf_l3_csum_replace_proto;
6215 case BPF_FUNC_l4_csum_replace:
6216 return &bpf_l4_csum_replace_proto;
6217 case BPF_FUNC_clone_redirect:
6218 return &bpf_clone_redirect_proto;
6219 case BPF_FUNC_get_cgroup_classid:
6220 return &bpf_get_cgroup_classid_proto;
6221 case BPF_FUNC_skb_vlan_push:
6222 return &bpf_skb_vlan_push_proto;
6223 case BPF_FUNC_skb_vlan_pop:
6224 return &bpf_skb_vlan_pop_proto;
6225 case BPF_FUNC_skb_change_proto:
6226 return &bpf_skb_change_proto_proto;
6227 case BPF_FUNC_skb_change_type:
6228 return &bpf_skb_change_type_proto;
6229 case BPF_FUNC_skb_adjust_room:
6230 return &bpf_skb_adjust_room_proto;
6231 case BPF_FUNC_skb_change_tail:
6232 return &bpf_skb_change_tail_proto;
6233 case BPF_FUNC_skb_change_head:
6234 return &bpf_skb_change_head_proto;
6235 case BPF_FUNC_skb_get_tunnel_key:
6236 return &bpf_skb_get_tunnel_key_proto;
6237 case BPF_FUNC_skb_set_tunnel_key:
6238 return bpf_get_skb_set_tunnel_proto(func_id);
6239 case BPF_FUNC_skb_get_tunnel_opt:
6240 return &bpf_skb_get_tunnel_opt_proto;
6241 case BPF_FUNC_skb_set_tunnel_opt:
6242 return bpf_get_skb_set_tunnel_proto(func_id);
6243 case BPF_FUNC_redirect:
6244 return &bpf_redirect_proto;
6245 case BPF_FUNC_get_route_realm:
6246 return &bpf_get_route_realm_proto;
6247 case BPF_FUNC_get_hash_recalc:
6248 return &bpf_get_hash_recalc_proto;
6249 case BPF_FUNC_set_hash_invalid:
6250 return &bpf_set_hash_invalid_proto;
6251 case BPF_FUNC_set_hash:
6252 return &bpf_set_hash_proto;
6253 case BPF_FUNC_perf_event_output:
6254 return &bpf_skb_event_output_proto;
6255 case BPF_FUNC_get_smp_processor_id:
6256 return &bpf_get_smp_processor_id_proto;
6257 case BPF_FUNC_skb_under_cgroup:
6258 return &bpf_skb_under_cgroup_proto;
6259 case BPF_FUNC_get_socket_cookie:
6260 return &bpf_get_socket_cookie_proto;
6261 case BPF_FUNC_get_socket_uid:
6262 return &bpf_get_socket_uid_proto;
6263 case BPF_FUNC_fib_lookup:
6264 return &bpf_skb_fib_lookup_proto;
6265 case BPF_FUNC_sk_fullsock:
6266 return &bpf_sk_fullsock_proto;
6267 case BPF_FUNC_sk_storage_get:
6268 return &bpf_sk_storage_get_proto;
6269 case BPF_FUNC_sk_storage_delete:
6270 return &bpf_sk_storage_delete_proto;
6271 #ifdef CONFIG_XFRM
6272 case BPF_FUNC_skb_get_xfrm_state:
6273 return &bpf_skb_get_xfrm_state_proto;
6274 #endif
6275 #ifdef CONFIG_SOCK_CGROUP_DATA
6276 case BPF_FUNC_skb_cgroup_id:
6277 return &bpf_skb_cgroup_id_proto;
6278 case BPF_FUNC_skb_ancestor_cgroup_id:
6279 return &bpf_skb_ancestor_cgroup_id_proto;
6280 #endif
6281 #ifdef CONFIG_INET
6282 case BPF_FUNC_sk_lookup_tcp:
6283 return &bpf_sk_lookup_tcp_proto;
6284 case BPF_FUNC_sk_lookup_udp:
6285 return &bpf_sk_lookup_udp_proto;
6286 case BPF_FUNC_sk_release:
6287 return &bpf_sk_release_proto;
6288 case BPF_FUNC_tcp_sock:
6289 return &bpf_tcp_sock_proto;
6290 case BPF_FUNC_get_listener_sock:
6291 return &bpf_get_listener_sock_proto;
6292 case BPF_FUNC_skc_lookup_tcp:
6293 return &bpf_skc_lookup_tcp_proto;
6294 case BPF_FUNC_tcp_check_syncookie:
6295 return &bpf_tcp_check_syncookie_proto;
6296 case BPF_FUNC_skb_ecn_set_ce:
6297 return &bpf_skb_ecn_set_ce_proto;
6298 case BPF_FUNC_tcp_gen_syncookie:
6299 return &bpf_tcp_gen_syncookie_proto;
6300 #endif
6301 default:
6302 return bpf_base_func_proto(func_id);
6303 }
6304 }
6305
6306 static const struct bpf_func_proto *
xdp_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6307 xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6308 {
6309 switch (func_id) {
6310 case BPF_FUNC_perf_event_output:
6311 return &bpf_xdp_event_output_proto;
6312 case BPF_FUNC_get_smp_processor_id:
6313 return &bpf_get_smp_processor_id_proto;
6314 case BPF_FUNC_csum_diff:
6315 return &bpf_csum_diff_proto;
6316 case BPF_FUNC_xdp_adjust_head:
6317 return &bpf_xdp_adjust_head_proto;
6318 case BPF_FUNC_xdp_adjust_meta:
6319 return &bpf_xdp_adjust_meta_proto;
6320 case BPF_FUNC_redirect:
6321 return &bpf_xdp_redirect_proto;
6322 case BPF_FUNC_redirect_map:
6323 return &bpf_xdp_redirect_map_proto;
6324 case BPF_FUNC_xdp_adjust_tail:
6325 return &bpf_xdp_adjust_tail_proto;
6326 case BPF_FUNC_fib_lookup:
6327 return &bpf_xdp_fib_lookup_proto;
6328 #ifdef CONFIG_INET
6329 case BPF_FUNC_sk_lookup_udp:
6330 return &bpf_xdp_sk_lookup_udp_proto;
6331 case BPF_FUNC_sk_lookup_tcp:
6332 return &bpf_xdp_sk_lookup_tcp_proto;
6333 case BPF_FUNC_sk_release:
6334 return &bpf_sk_release_proto;
6335 case BPF_FUNC_skc_lookup_tcp:
6336 return &bpf_xdp_skc_lookup_tcp_proto;
6337 case BPF_FUNC_tcp_check_syncookie:
6338 return &bpf_tcp_check_syncookie_proto;
6339 case BPF_FUNC_tcp_gen_syncookie:
6340 return &bpf_tcp_gen_syncookie_proto;
6341 #endif
6342 default:
6343 return bpf_base_func_proto(func_id);
6344 }
6345 }
6346
6347 const struct bpf_func_proto bpf_sock_map_update_proto __weak;
6348 const struct bpf_func_proto bpf_sock_hash_update_proto __weak;
6349
6350 static const struct bpf_func_proto *
sock_ops_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6351 sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6352 {
6353 switch (func_id) {
6354 case BPF_FUNC_setsockopt:
6355 return &bpf_setsockopt_proto;
6356 case BPF_FUNC_getsockopt:
6357 return &bpf_getsockopt_proto;
6358 case BPF_FUNC_sock_ops_cb_flags_set:
6359 return &bpf_sock_ops_cb_flags_set_proto;
6360 case BPF_FUNC_sock_map_update:
6361 return &bpf_sock_map_update_proto;
6362 case BPF_FUNC_sock_hash_update:
6363 return &bpf_sock_hash_update_proto;
6364 case BPF_FUNC_get_socket_cookie:
6365 return &bpf_get_socket_cookie_sock_ops_proto;
6366 case BPF_FUNC_get_local_storage:
6367 return &bpf_get_local_storage_proto;
6368 case BPF_FUNC_perf_event_output:
6369 return &bpf_sockopt_event_output_proto;
6370 case BPF_FUNC_sk_storage_get:
6371 return &bpf_sk_storage_get_proto;
6372 case BPF_FUNC_sk_storage_delete:
6373 return &bpf_sk_storage_delete_proto;
6374 #ifdef CONFIG_INET
6375 case BPF_FUNC_tcp_sock:
6376 return &bpf_tcp_sock_proto;
6377 #endif /* CONFIG_INET */
6378 default:
6379 return bpf_base_func_proto(func_id);
6380 }
6381 }
6382
6383 const struct bpf_func_proto bpf_msg_redirect_map_proto __weak;
6384 const struct bpf_func_proto bpf_msg_redirect_hash_proto __weak;
6385
6386 static const struct bpf_func_proto *
sk_msg_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6387 sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6388 {
6389 switch (func_id) {
6390 case BPF_FUNC_msg_redirect_map:
6391 return &bpf_msg_redirect_map_proto;
6392 case BPF_FUNC_msg_redirect_hash:
6393 return &bpf_msg_redirect_hash_proto;
6394 case BPF_FUNC_msg_apply_bytes:
6395 return &bpf_msg_apply_bytes_proto;
6396 case BPF_FUNC_msg_cork_bytes:
6397 return &bpf_msg_cork_bytes_proto;
6398 case BPF_FUNC_msg_pull_data:
6399 return &bpf_msg_pull_data_proto;
6400 case BPF_FUNC_msg_push_data:
6401 return &bpf_msg_push_data_proto;
6402 case BPF_FUNC_msg_pop_data:
6403 return &bpf_msg_pop_data_proto;
6404 default:
6405 return bpf_base_func_proto(func_id);
6406 }
6407 }
6408
6409 const struct bpf_func_proto bpf_sk_redirect_map_proto __weak;
6410 const struct bpf_func_proto bpf_sk_redirect_hash_proto __weak;
6411
6412 static const struct bpf_func_proto *
sk_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6413 sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6414 {
6415 switch (func_id) {
6416 case BPF_FUNC_skb_store_bytes:
6417 return &bpf_skb_store_bytes_proto;
6418 case BPF_FUNC_skb_load_bytes:
6419 return &bpf_skb_load_bytes_proto;
6420 case BPF_FUNC_skb_pull_data:
6421 return &sk_skb_pull_data_proto;
6422 case BPF_FUNC_skb_change_tail:
6423 return &sk_skb_change_tail_proto;
6424 case BPF_FUNC_skb_change_head:
6425 return &sk_skb_change_head_proto;
6426 case BPF_FUNC_get_socket_cookie:
6427 return &bpf_get_socket_cookie_proto;
6428 case BPF_FUNC_get_socket_uid:
6429 return &bpf_get_socket_uid_proto;
6430 case BPF_FUNC_sk_redirect_map:
6431 return &bpf_sk_redirect_map_proto;
6432 case BPF_FUNC_sk_redirect_hash:
6433 return &bpf_sk_redirect_hash_proto;
6434 case BPF_FUNC_perf_event_output:
6435 return &bpf_skb_event_output_proto;
6436 #ifdef CONFIG_INET
6437 case BPF_FUNC_sk_lookup_tcp:
6438 return &bpf_sk_lookup_tcp_proto;
6439 case BPF_FUNC_sk_lookup_udp:
6440 return &bpf_sk_lookup_udp_proto;
6441 case BPF_FUNC_sk_release:
6442 return &bpf_sk_release_proto;
6443 case BPF_FUNC_skc_lookup_tcp:
6444 return &bpf_skc_lookup_tcp_proto;
6445 #endif
6446 default:
6447 return bpf_base_func_proto(func_id);
6448 }
6449 }
6450
6451 static const struct bpf_func_proto *
flow_dissector_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6452 flow_dissector_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6453 {
6454 switch (func_id) {
6455 case BPF_FUNC_skb_load_bytes:
6456 return &bpf_flow_dissector_load_bytes_proto;
6457 default:
6458 return bpf_base_func_proto(func_id);
6459 }
6460 }
6461
6462 static const struct bpf_func_proto *
lwt_out_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6463 lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6464 {
6465 switch (func_id) {
6466 case BPF_FUNC_skb_load_bytes:
6467 return &bpf_skb_load_bytes_proto;
6468 case BPF_FUNC_skb_pull_data:
6469 return &bpf_skb_pull_data_proto;
6470 case BPF_FUNC_csum_diff:
6471 return &bpf_csum_diff_proto;
6472 case BPF_FUNC_get_cgroup_classid:
6473 return &bpf_get_cgroup_classid_proto;
6474 case BPF_FUNC_get_route_realm:
6475 return &bpf_get_route_realm_proto;
6476 case BPF_FUNC_get_hash_recalc:
6477 return &bpf_get_hash_recalc_proto;
6478 case BPF_FUNC_perf_event_output:
6479 return &bpf_skb_event_output_proto;
6480 case BPF_FUNC_get_smp_processor_id:
6481 return &bpf_get_smp_processor_id_proto;
6482 case BPF_FUNC_skb_under_cgroup:
6483 return &bpf_skb_under_cgroup_proto;
6484 default:
6485 return bpf_base_func_proto(func_id);
6486 }
6487 }
6488
6489 static const struct bpf_func_proto *
lwt_in_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6490 lwt_in_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6491 {
6492 switch (func_id) {
6493 case BPF_FUNC_lwt_push_encap:
6494 return &bpf_lwt_in_push_encap_proto;
6495 default:
6496 return lwt_out_func_proto(func_id, prog);
6497 }
6498 }
6499
6500 static const struct bpf_func_proto *
lwt_xmit_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6501 lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6502 {
6503 switch (func_id) {
6504 case BPF_FUNC_skb_get_tunnel_key:
6505 return &bpf_skb_get_tunnel_key_proto;
6506 case BPF_FUNC_skb_set_tunnel_key:
6507 return bpf_get_skb_set_tunnel_proto(func_id);
6508 case BPF_FUNC_skb_get_tunnel_opt:
6509 return &bpf_skb_get_tunnel_opt_proto;
6510 case BPF_FUNC_skb_set_tunnel_opt:
6511 return bpf_get_skb_set_tunnel_proto(func_id);
6512 case BPF_FUNC_redirect:
6513 return &bpf_redirect_proto;
6514 case BPF_FUNC_clone_redirect:
6515 return &bpf_clone_redirect_proto;
6516 case BPF_FUNC_skb_change_tail:
6517 return &bpf_skb_change_tail_proto;
6518 case BPF_FUNC_skb_change_head:
6519 return &bpf_skb_change_head_proto;
6520 case BPF_FUNC_skb_store_bytes:
6521 return &bpf_skb_store_bytes_proto;
6522 case BPF_FUNC_csum_update:
6523 return &bpf_csum_update_proto;
6524 case BPF_FUNC_l3_csum_replace:
6525 return &bpf_l3_csum_replace_proto;
6526 case BPF_FUNC_l4_csum_replace:
6527 return &bpf_l4_csum_replace_proto;
6528 case BPF_FUNC_set_hash_invalid:
6529 return &bpf_set_hash_invalid_proto;
6530 case BPF_FUNC_lwt_push_encap:
6531 return &bpf_lwt_xmit_push_encap_proto;
6532 default:
6533 return lwt_out_func_proto(func_id, prog);
6534 }
6535 }
6536
6537 static const struct bpf_func_proto *
lwt_seg6local_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6538 lwt_seg6local_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6539 {
6540 switch (func_id) {
6541 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
6542 case BPF_FUNC_lwt_seg6_store_bytes:
6543 return &bpf_lwt_seg6_store_bytes_proto;
6544 case BPF_FUNC_lwt_seg6_action:
6545 return &bpf_lwt_seg6_action_proto;
6546 case BPF_FUNC_lwt_seg6_adjust_srh:
6547 return &bpf_lwt_seg6_adjust_srh_proto;
6548 #endif
6549 default:
6550 return lwt_out_func_proto(func_id, prog);
6551 }
6552 }
6553
bpf_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)6554 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
6555 const struct bpf_prog *prog,
6556 struct bpf_insn_access_aux *info)
6557 {
6558 const int size_default = sizeof(__u32);
6559
6560 if (off < 0 || off >= sizeof(struct __sk_buff))
6561 return false;
6562
6563 /* The verifier guarantees that size > 0. */
6564 if (off % size != 0)
6565 return false;
6566
6567 switch (off) {
6568 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
6569 if (off + size > offsetofend(struct __sk_buff, cb[4]))
6570 return false;
6571 break;
6572 case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
6573 case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
6574 case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
6575 case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
6576 case bpf_ctx_range(struct __sk_buff, data):
6577 case bpf_ctx_range(struct __sk_buff, data_meta):
6578 case bpf_ctx_range(struct __sk_buff, data_end):
6579 if (size != size_default)
6580 return false;
6581 break;
6582 case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
6583 return false;
6584 case bpf_ctx_range(struct __sk_buff, tstamp):
6585 if (size != sizeof(__u64))
6586 return false;
6587 break;
6588 case offsetof(struct __sk_buff, sk):
6589 if (type == BPF_WRITE || size != sizeof(__u64))
6590 return false;
6591 info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
6592 break;
6593 default:
6594 /* Only narrow read access allowed for now. */
6595 if (type == BPF_WRITE) {
6596 if (size != size_default)
6597 return false;
6598 } else {
6599 bpf_ctx_record_field_size(info, size_default);
6600 if (!bpf_ctx_narrow_access_ok(off, size, size_default))
6601 return false;
6602 }
6603 }
6604
6605 return true;
6606 }
6607
sk_filter_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)6608 static bool sk_filter_is_valid_access(int off, int size,
6609 enum bpf_access_type type,
6610 const struct bpf_prog *prog,
6611 struct bpf_insn_access_aux *info)
6612 {
6613 switch (off) {
6614 case bpf_ctx_range(struct __sk_buff, tc_classid):
6615 case bpf_ctx_range(struct __sk_buff, data):
6616 case bpf_ctx_range(struct __sk_buff, data_meta):
6617 case bpf_ctx_range(struct __sk_buff, data_end):
6618 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
6619 case bpf_ctx_range(struct __sk_buff, tstamp):
6620 case bpf_ctx_range(struct __sk_buff, wire_len):
6621 return false;
6622 }
6623
6624 if (type == BPF_WRITE) {
6625 switch (off) {
6626 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
6627 break;
6628 default:
6629 return false;
6630 }
6631 }
6632
6633 return bpf_skb_is_valid_access(off, size, type, prog, info);
6634 }
6635
cg_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)6636 static bool cg_skb_is_valid_access(int off, int size,
6637 enum bpf_access_type type,
6638 const struct bpf_prog *prog,
6639 struct bpf_insn_access_aux *info)
6640 {
6641 switch (off) {
6642 case bpf_ctx_range(struct __sk_buff, tc_classid):
6643 case bpf_ctx_range(struct __sk_buff, data_meta):
6644 case bpf_ctx_range(struct __sk_buff, wire_len):
6645 return false;
6646 case bpf_ctx_range(struct __sk_buff, data):
6647 case bpf_ctx_range(struct __sk_buff, data_end):
6648 if (!capable(CAP_SYS_ADMIN))
6649 return false;
6650 break;
6651 }
6652
6653 if (type == BPF_WRITE) {
6654 switch (off) {
6655 case bpf_ctx_range(struct __sk_buff, mark):
6656 case bpf_ctx_range(struct __sk_buff, priority):
6657 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
6658 break;
6659 case bpf_ctx_range(struct __sk_buff, tstamp):
6660 if (!capable(CAP_SYS_ADMIN))
6661 return false;
6662 break;
6663 default:
6664 return false;
6665 }
6666 }
6667
6668 switch (off) {
6669 case bpf_ctx_range(struct __sk_buff, data):
6670 info->reg_type = PTR_TO_PACKET;
6671 break;
6672 case bpf_ctx_range(struct __sk_buff, data_end):
6673 info->reg_type = PTR_TO_PACKET_END;
6674 break;
6675 }
6676
6677 return bpf_skb_is_valid_access(off, size, type, prog, info);
6678 }
6679
lwt_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)6680 static bool lwt_is_valid_access(int off, int size,
6681 enum bpf_access_type type,
6682 const struct bpf_prog *prog,
6683 struct bpf_insn_access_aux *info)
6684 {
6685 switch (off) {
6686 case bpf_ctx_range(struct __sk_buff, tc_classid):
6687 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
6688 case bpf_ctx_range(struct __sk_buff, data_meta):
6689 case bpf_ctx_range(struct __sk_buff, tstamp):
6690 case bpf_ctx_range(struct __sk_buff, wire_len):
6691 return false;
6692 }
6693
6694 if (type == BPF_WRITE) {
6695 switch (off) {
6696 case bpf_ctx_range(struct __sk_buff, mark):
6697 case bpf_ctx_range(struct __sk_buff, priority):
6698 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
6699 break;
6700 default:
6701 return false;
6702 }
6703 }
6704
6705 switch (off) {
6706 case bpf_ctx_range(struct __sk_buff, data):
6707 info->reg_type = PTR_TO_PACKET;
6708 break;
6709 case bpf_ctx_range(struct __sk_buff, data_end):
6710 info->reg_type = PTR_TO_PACKET_END;
6711 break;
6712 }
6713
6714 return bpf_skb_is_valid_access(off, size, type, prog, info);
6715 }
6716
6717 /* Attach type specific accesses */
__sock_filter_check_attach_type(int off,enum bpf_access_type access_type,enum bpf_attach_type attach_type)6718 static bool __sock_filter_check_attach_type(int off,
6719 enum bpf_access_type access_type,
6720 enum bpf_attach_type attach_type)
6721 {
6722 switch (off) {
6723 case offsetof(struct bpf_sock, bound_dev_if):
6724 case offsetof(struct bpf_sock, mark):
6725 case offsetof(struct bpf_sock, priority):
6726 switch (attach_type) {
6727 case BPF_CGROUP_INET_SOCK_CREATE:
6728 goto full_access;
6729 default:
6730 return false;
6731 }
6732 case bpf_ctx_range(struct bpf_sock, src_ip4):
6733 switch (attach_type) {
6734 case BPF_CGROUP_INET4_POST_BIND:
6735 goto read_only;
6736 default:
6737 return false;
6738 }
6739 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
6740 switch (attach_type) {
6741 case BPF_CGROUP_INET6_POST_BIND:
6742 goto read_only;
6743 default:
6744 return false;
6745 }
6746 case bpf_ctx_range(struct bpf_sock, src_port):
6747 switch (attach_type) {
6748 case BPF_CGROUP_INET4_POST_BIND:
6749 case BPF_CGROUP_INET6_POST_BIND:
6750 goto read_only;
6751 default:
6752 return false;
6753 }
6754 }
6755 read_only:
6756 return access_type == BPF_READ;
6757 full_access:
6758 return true;
6759 }
6760
bpf_sock_common_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)6761 bool bpf_sock_common_is_valid_access(int off, int size,
6762 enum bpf_access_type type,
6763 struct bpf_insn_access_aux *info)
6764 {
6765 switch (off) {
6766 case bpf_ctx_range_till(struct bpf_sock, type, priority):
6767 return false;
6768 default:
6769 return bpf_sock_is_valid_access(off, size, type, info);
6770 }
6771 }
6772
bpf_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)6773 bool bpf_sock_is_valid_access(int off, int size, enum bpf_access_type type,
6774 struct bpf_insn_access_aux *info)
6775 {
6776 const int size_default = sizeof(__u32);
6777 int field_size;
6778
6779 if (off < 0 || off >= sizeof(struct bpf_sock))
6780 return false;
6781 if (off % size != 0)
6782 return false;
6783
6784 switch (off) {
6785 case offsetof(struct bpf_sock, state):
6786 case offsetof(struct bpf_sock, family):
6787 case offsetof(struct bpf_sock, type):
6788 case offsetof(struct bpf_sock, protocol):
6789 case offsetof(struct bpf_sock, src_port):
6790 case bpf_ctx_range(struct bpf_sock, src_ip4):
6791 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
6792 case bpf_ctx_range(struct bpf_sock, dst_ip4):
6793 case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
6794 bpf_ctx_record_field_size(info, size_default);
6795 return bpf_ctx_narrow_access_ok(off, size, size_default);
6796 case bpf_ctx_range(struct bpf_sock, dst_port):
6797 field_size = size == size_default ?
6798 size_default : sizeof_field(struct bpf_sock, dst_port);
6799 bpf_ctx_record_field_size(info, field_size);
6800 return bpf_ctx_narrow_access_ok(off, size, field_size);
6801 case offsetofend(struct bpf_sock, dst_port) ...
6802 offsetof(struct bpf_sock, dst_ip4) - 1:
6803 return false;
6804 }
6805
6806 return size == size_default;
6807 }
6808
sock_filter_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)6809 static bool sock_filter_is_valid_access(int off, int size,
6810 enum bpf_access_type type,
6811 const struct bpf_prog *prog,
6812 struct bpf_insn_access_aux *info)
6813 {
6814 if (!bpf_sock_is_valid_access(off, size, type, info))
6815 return false;
6816 return __sock_filter_check_attach_type(off, type,
6817 prog->expected_attach_type);
6818 }
6819
bpf_noop_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)6820 static int bpf_noop_prologue(struct bpf_insn *insn_buf, bool direct_write,
6821 const struct bpf_prog *prog)
6822 {
6823 /* Neither direct read nor direct write requires any preliminary
6824 * action.
6825 */
6826 return 0;
6827 }
6828
bpf_unclone_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog,int drop_verdict)6829 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
6830 const struct bpf_prog *prog, int drop_verdict)
6831 {
6832 struct bpf_insn *insn = insn_buf;
6833
6834 if (!direct_write)
6835 return 0;
6836
6837 /* if (!skb->cloned)
6838 * goto start;
6839 *
6840 * (Fast-path, otherwise approximation that we might be
6841 * a clone, do the rest in helper.)
6842 */
6843 *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET());
6844 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
6845 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
6846
6847 /* ret = bpf_skb_pull_data(skb, 0); */
6848 *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
6849 *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
6850 *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
6851 BPF_FUNC_skb_pull_data);
6852 /* if (!ret)
6853 * goto restore;
6854 * return TC_ACT_SHOT;
6855 */
6856 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
6857 *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
6858 *insn++ = BPF_EXIT_INSN();
6859
6860 /* restore: */
6861 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
6862 /* start: */
6863 *insn++ = prog->insnsi[0];
6864
6865 return insn - insn_buf;
6866 }
6867
bpf_gen_ld_abs(const struct bpf_insn * orig,struct bpf_insn * insn_buf)6868 static int bpf_gen_ld_abs(const struct bpf_insn *orig,
6869 struct bpf_insn *insn_buf)
6870 {
6871 bool indirect = BPF_MODE(orig->code) == BPF_IND;
6872 struct bpf_insn *insn = insn_buf;
6873
6874 if (!indirect) {
6875 *insn++ = BPF_MOV64_IMM(BPF_REG_2, orig->imm);
6876 } else {
6877 *insn++ = BPF_MOV64_REG(BPF_REG_2, orig->src_reg);
6878 if (orig->imm)
6879 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, orig->imm);
6880 }
6881 /* We're guaranteed here that CTX is in R6. */
6882 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_CTX);
6883
6884 switch (BPF_SIZE(orig->code)) {
6885 case BPF_B:
6886 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8_no_cache);
6887 break;
6888 case BPF_H:
6889 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16_no_cache);
6890 break;
6891 case BPF_W:
6892 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32_no_cache);
6893 break;
6894 }
6895
6896 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 2);
6897 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_0, BPF_REG_0);
6898 *insn++ = BPF_EXIT_INSN();
6899
6900 return insn - insn_buf;
6901 }
6902
tc_cls_act_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)6903 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
6904 const struct bpf_prog *prog)
6905 {
6906 return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
6907 }
6908
tc_cls_act_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)6909 static bool tc_cls_act_is_valid_access(int off, int size,
6910 enum bpf_access_type type,
6911 const struct bpf_prog *prog,
6912 struct bpf_insn_access_aux *info)
6913 {
6914 if (type == BPF_WRITE) {
6915 switch (off) {
6916 case bpf_ctx_range(struct __sk_buff, mark):
6917 case bpf_ctx_range(struct __sk_buff, tc_index):
6918 case bpf_ctx_range(struct __sk_buff, priority):
6919 case bpf_ctx_range(struct __sk_buff, tc_classid):
6920 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
6921 case bpf_ctx_range(struct __sk_buff, tstamp):
6922 case bpf_ctx_range(struct __sk_buff, queue_mapping):
6923 break;
6924 default:
6925 return false;
6926 }
6927 }
6928
6929 switch (off) {
6930 case bpf_ctx_range(struct __sk_buff, data):
6931 info->reg_type = PTR_TO_PACKET;
6932 break;
6933 case bpf_ctx_range(struct __sk_buff, data_meta):
6934 info->reg_type = PTR_TO_PACKET_META;
6935 break;
6936 case bpf_ctx_range(struct __sk_buff, data_end):
6937 info->reg_type = PTR_TO_PACKET_END;
6938 break;
6939 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
6940 return false;
6941 }
6942
6943 return bpf_skb_is_valid_access(off, size, type, prog, info);
6944 }
6945
__is_valid_xdp_access(int off,int size)6946 static bool __is_valid_xdp_access(int off, int size)
6947 {
6948 if (off < 0 || off >= sizeof(struct xdp_md))
6949 return false;
6950 if (off % size != 0)
6951 return false;
6952 if (size != sizeof(__u32))
6953 return false;
6954
6955 return true;
6956 }
6957
xdp_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)6958 static bool xdp_is_valid_access(int off, int size,
6959 enum bpf_access_type type,
6960 const struct bpf_prog *prog,
6961 struct bpf_insn_access_aux *info)
6962 {
6963 if (type == BPF_WRITE) {
6964 if (bpf_prog_is_dev_bound(prog->aux)) {
6965 switch (off) {
6966 case offsetof(struct xdp_md, rx_queue_index):
6967 return __is_valid_xdp_access(off, size);
6968 }
6969 }
6970 return false;
6971 }
6972
6973 switch (off) {
6974 case offsetof(struct xdp_md, data):
6975 info->reg_type = PTR_TO_PACKET;
6976 break;
6977 case offsetof(struct xdp_md, data_meta):
6978 info->reg_type = PTR_TO_PACKET_META;
6979 break;
6980 case offsetof(struct xdp_md, data_end):
6981 info->reg_type = PTR_TO_PACKET_END;
6982 break;
6983 }
6984
6985 return __is_valid_xdp_access(off, size);
6986 }
6987
bpf_warn_invalid_xdp_action(u32 act)6988 void bpf_warn_invalid_xdp_action(u32 act)
6989 {
6990 const u32 act_max = XDP_REDIRECT;
6991
6992 pr_warn_once("%s XDP return value %u, expect packet loss!\n",
6993 act > act_max ? "Illegal" : "Driver unsupported",
6994 act);
6995 }
6996 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
6997
sock_addr_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)6998 static bool sock_addr_is_valid_access(int off, int size,
6999 enum bpf_access_type type,
7000 const struct bpf_prog *prog,
7001 struct bpf_insn_access_aux *info)
7002 {
7003 const int size_default = sizeof(__u32);
7004
7005 if (off < 0 || off >= sizeof(struct bpf_sock_addr))
7006 return false;
7007 if (off % size != 0)
7008 return false;
7009
7010 /* Disallow access to IPv6 fields from IPv4 contex and vise
7011 * versa.
7012 */
7013 switch (off) {
7014 case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
7015 switch (prog->expected_attach_type) {
7016 case BPF_CGROUP_INET4_BIND:
7017 case BPF_CGROUP_INET4_CONNECT:
7018 case BPF_CGROUP_UDP4_SENDMSG:
7019 case BPF_CGROUP_UDP4_RECVMSG:
7020 break;
7021 default:
7022 return false;
7023 }
7024 break;
7025 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
7026 switch (prog->expected_attach_type) {
7027 case BPF_CGROUP_INET6_BIND:
7028 case BPF_CGROUP_INET6_CONNECT:
7029 case BPF_CGROUP_UDP6_SENDMSG:
7030 case BPF_CGROUP_UDP6_RECVMSG:
7031 break;
7032 default:
7033 return false;
7034 }
7035 break;
7036 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
7037 switch (prog->expected_attach_type) {
7038 case BPF_CGROUP_UDP4_SENDMSG:
7039 break;
7040 default:
7041 return false;
7042 }
7043 break;
7044 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
7045 msg_src_ip6[3]):
7046 switch (prog->expected_attach_type) {
7047 case BPF_CGROUP_UDP6_SENDMSG:
7048 break;
7049 default:
7050 return false;
7051 }
7052 break;
7053 }
7054
7055 switch (off) {
7056 case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
7057 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
7058 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
7059 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
7060 msg_src_ip6[3]):
7061 if (type == BPF_READ) {
7062 bpf_ctx_record_field_size(info, size_default);
7063
7064 if (bpf_ctx_wide_access_ok(off, size,
7065 struct bpf_sock_addr,
7066 user_ip6))
7067 return true;
7068
7069 if (bpf_ctx_wide_access_ok(off, size,
7070 struct bpf_sock_addr,
7071 msg_src_ip6))
7072 return true;
7073
7074 if (!bpf_ctx_narrow_access_ok(off, size, size_default))
7075 return false;
7076 } else {
7077 if (bpf_ctx_wide_access_ok(off, size,
7078 struct bpf_sock_addr,
7079 user_ip6))
7080 return true;
7081
7082 if (bpf_ctx_wide_access_ok(off, size,
7083 struct bpf_sock_addr,
7084 msg_src_ip6))
7085 return true;
7086
7087 if (size != size_default)
7088 return false;
7089 }
7090 break;
7091 case bpf_ctx_range(struct bpf_sock_addr, user_port):
7092 if (size != size_default)
7093 return false;
7094 break;
7095 case offsetof(struct bpf_sock_addr, sk):
7096 if (type != BPF_READ)
7097 return false;
7098 if (size != sizeof(__u64))
7099 return false;
7100 info->reg_type = PTR_TO_SOCKET;
7101 break;
7102 default:
7103 if (type == BPF_READ) {
7104 if (size != size_default)
7105 return false;
7106 } else {
7107 return false;
7108 }
7109 }
7110
7111 return true;
7112 }
7113
sock_ops_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)7114 static bool sock_ops_is_valid_access(int off, int size,
7115 enum bpf_access_type type,
7116 const struct bpf_prog *prog,
7117 struct bpf_insn_access_aux *info)
7118 {
7119 const int size_default = sizeof(__u32);
7120
7121 if (off < 0 || off >= sizeof(struct bpf_sock_ops))
7122 return false;
7123
7124 /* The verifier guarantees that size > 0. */
7125 if (off % size != 0)
7126 return false;
7127
7128 if (type == BPF_WRITE) {
7129 switch (off) {
7130 case offsetof(struct bpf_sock_ops, reply):
7131 case offsetof(struct bpf_sock_ops, sk_txhash):
7132 if (size != size_default)
7133 return false;
7134 break;
7135 default:
7136 return false;
7137 }
7138 } else {
7139 switch (off) {
7140 case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received,
7141 bytes_acked):
7142 if (size != sizeof(__u64))
7143 return false;
7144 break;
7145 case offsetof(struct bpf_sock_ops, sk):
7146 if (size != sizeof(__u64))
7147 return false;
7148 info->reg_type = PTR_TO_SOCKET_OR_NULL;
7149 break;
7150 default:
7151 if (size != size_default)
7152 return false;
7153 break;
7154 }
7155 }
7156
7157 return true;
7158 }
7159
sk_skb_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)7160 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
7161 const struct bpf_prog *prog)
7162 {
7163 return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
7164 }
7165
sk_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)7166 static bool sk_skb_is_valid_access(int off, int size,
7167 enum bpf_access_type type,
7168 const struct bpf_prog *prog,
7169 struct bpf_insn_access_aux *info)
7170 {
7171 switch (off) {
7172 case bpf_ctx_range(struct __sk_buff, tc_classid):
7173 case bpf_ctx_range(struct __sk_buff, data_meta):
7174 case bpf_ctx_range(struct __sk_buff, tstamp):
7175 case bpf_ctx_range(struct __sk_buff, wire_len):
7176 return false;
7177 }
7178
7179 if (type == BPF_WRITE) {
7180 switch (off) {
7181 case bpf_ctx_range(struct __sk_buff, tc_index):
7182 case bpf_ctx_range(struct __sk_buff, priority):
7183 break;
7184 default:
7185 return false;
7186 }
7187 }
7188
7189 switch (off) {
7190 case bpf_ctx_range(struct __sk_buff, mark):
7191 return false;
7192 case bpf_ctx_range(struct __sk_buff, data):
7193 info->reg_type = PTR_TO_PACKET;
7194 break;
7195 case bpf_ctx_range(struct __sk_buff, data_end):
7196 info->reg_type = PTR_TO_PACKET_END;
7197 break;
7198 }
7199
7200 return bpf_skb_is_valid_access(off, size, type, prog, info);
7201 }
7202
sk_msg_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)7203 static bool sk_msg_is_valid_access(int off, int size,
7204 enum bpf_access_type type,
7205 const struct bpf_prog *prog,
7206 struct bpf_insn_access_aux *info)
7207 {
7208 if (type == BPF_WRITE)
7209 return false;
7210
7211 if (off % size != 0)
7212 return false;
7213
7214 switch (off) {
7215 case offsetof(struct sk_msg_md, data):
7216 info->reg_type = PTR_TO_PACKET;
7217 if (size != sizeof(__u64))
7218 return false;
7219 break;
7220 case offsetof(struct sk_msg_md, data_end):
7221 info->reg_type = PTR_TO_PACKET_END;
7222 if (size != sizeof(__u64))
7223 return false;
7224 break;
7225 case bpf_ctx_range(struct sk_msg_md, family):
7226 case bpf_ctx_range(struct sk_msg_md, remote_ip4):
7227 case bpf_ctx_range(struct sk_msg_md, local_ip4):
7228 case bpf_ctx_range_till(struct sk_msg_md, remote_ip6[0], remote_ip6[3]):
7229 case bpf_ctx_range_till(struct sk_msg_md, local_ip6[0], local_ip6[3]):
7230 case bpf_ctx_range(struct sk_msg_md, remote_port):
7231 case bpf_ctx_range(struct sk_msg_md, local_port):
7232 case bpf_ctx_range(struct sk_msg_md, size):
7233 if (size != sizeof(__u32))
7234 return false;
7235 break;
7236 default:
7237 return false;
7238 }
7239 return true;
7240 }
7241
flow_dissector_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)7242 static bool flow_dissector_is_valid_access(int off, int size,
7243 enum bpf_access_type type,
7244 const struct bpf_prog *prog,
7245 struct bpf_insn_access_aux *info)
7246 {
7247 const int size_default = sizeof(__u32);
7248
7249 if (off < 0 || off >= sizeof(struct __sk_buff))
7250 return false;
7251
7252 if (type == BPF_WRITE)
7253 return false;
7254
7255 switch (off) {
7256 case bpf_ctx_range(struct __sk_buff, data):
7257 if (size != size_default)
7258 return false;
7259 info->reg_type = PTR_TO_PACKET;
7260 return true;
7261 case bpf_ctx_range(struct __sk_buff, data_end):
7262 if (size != size_default)
7263 return false;
7264 info->reg_type = PTR_TO_PACKET_END;
7265 return true;
7266 case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
7267 if (size != sizeof(__u64))
7268 return false;
7269 info->reg_type = PTR_TO_FLOW_KEYS;
7270 return true;
7271 default:
7272 return false;
7273 }
7274 }
7275
flow_dissector_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)7276 static u32 flow_dissector_convert_ctx_access(enum bpf_access_type type,
7277 const struct bpf_insn *si,
7278 struct bpf_insn *insn_buf,
7279 struct bpf_prog *prog,
7280 u32 *target_size)
7281
7282 {
7283 struct bpf_insn *insn = insn_buf;
7284
7285 switch (si->off) {
7286 case offsetof(struct __sk_buff, data):
7287 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data),
7288 si->dst_reg, si->src_reg,
7289 offsetof(struct bpf_flow_dissector, data));
7290 break;
7291
7292 case offsetof(struct __sk_buff, data_end):
7293 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data_end),
7294 si->dst_reg, si->src_reg,
7295 offsetof(struct bpf_flow_dissector, data_end));
7296 break;
7297
7298 case offsetof(struct __sk_buff, flow_keys):
7299 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, flow_keys),
7300 si->dst_reg, si->src_reg,
7301 offsetof(struct bpf_flow_dissector, flow_keys));
7302 break;
7303 }
7304
7305 return insn - insn_buf;
7306 }
7307
bpf_convert_shinfo_access(const struct bpf_insn * si,struct bpf_insn * insn)7308 static struct bpf_insn *bpf_convert_shinfo_access(const struct bpf_insn *si,
7309 struct bpf_insn *insn)
7310 {
7311 /* si->dst_reg = skb_shinfo(SKB); */
7312 #ifdef NET_SKBUFF_DATA_USES_OFFSET
7313 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
7314 BPF_REG_AX, si->src_reg,
7315 offsetof(struct sk_buff, end));
7316 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, head),
7317 si->dst_reg, si->src_reg,
7318 offsetof(struct sk_buff, head));
7319 *insn++ = BPF_ALU64_REG(BPF_ADD, si->dst_reg, BPF_REG_AX);
7320 #else
7321 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
7322 si->dst_reg, si->src_reg,
7323 offsetof(struct sk_buff, end));
7324 #endif
7325
7326 return insn;
7327 }
7328
bpf_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)7329 static u32 bpf_convert_ctx_access(enum bpf_access_type type,
7330 const struct bpf_insn *si,
7331 struct bpf_insn *insn_buf,
7332 struct bpf_prog *prog, u32 *target_size)
7333 {
7334 struct bpf_insn *insn = insn_buf;
7335 int off;
7336
7337 switch (si->off) {
7338 case offsetof(struct __sk_buff, len):
7339 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7340 bpf_target_off(struct sk_buff, len, 4,
7341 target_size));
7342 break;
7343
7344 case offsetof(struct __sk_buff, protocol):
7345 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
7346 bpf_target_off(struct sk_buff, protocol, 2,
7347 target_size));
7348 break;
7349
7350 case offsetof(struct __sk_buff, vlan_proto):
7351 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
7352 bpf_target_off(struct sk_buff, vlan_proto, 2,
7353 target_size));
7354 break;
7355
7356 case offsetof(struct __sk_buff, priority):
7357 if (type == BPF_WRITE)
7358 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
7359 bpf_target_off(struct sk_buff, priority, 4,
7360 target_size));
7361 else
7362 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7363 bpf_target_off(struct sk_buff, priority, 4,
7364 target_size));
7365 break;
7366
7367 case offsetof(struct __sk_buff, ingress_ifindex):
7368 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7369 bpf_target_off(struct sk_buff, skb_iif, 4,
7370 target_size));
7371 break;
7372
7373 case offsetof(struct __sk_buff, ifindex):
7374 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
7375 si->dst_reg, si->src_reg,
7376 offsetof(struct sk_buff, dev));
7377 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
7378 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
7379 bpf_target_off(struct net_device, ifindex, 4,
7380 target_size));
7381 break;
7382
7383 case offsetof(struct __sk_buff, hash):
7384 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7385 bpf_target_off(struct sk_buff, hash, 4,
7386 target_size));
7387 break;
7388
7389 case offsetof(struct __sk_buff, mark):
7390 if (type == BPF_WRITE)
7391 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
7392 bpf_target_off(struct sk_buff, mark, 4,
7393 target_size));
7394 else
7395 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7396 bpf_target_off(struct sk_buff, mark, 4,
7397 target_size));
7398 break;
7399
7400 case offsetof(struct __sk_buff, pkt_type):
7401 *target_size = 1;
7402 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
7403 PKT_TYPE_OFFSET());
7404 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
7405 #ifdef __BIG_ENDIAN_BITFIELD
7406 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
7407 #endif
7408 break;
7409
7410 case offsetof(struct __sk_buff, queue_mapping):
7411 if (type == BPF_WRITE) {
7412 *insn++ = BPF_JMP_IMM(BPF_JGE, si->src_reg, NO_QUEUE_MAPPING, 1);
7413 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
7414 bpf_target_off(struct sk_buff,
7415 queue_mapping,
7416 2, target_size));
7417 } else {
7418 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
7419 bpf_target_off(struct sk_buff,
7420 queue_mapping,
7421 2, target_size));
7422 }
7423 break;
7424
7425 case offsetof(struct __sk_buff, vlan_present):
7426 *target_size = 1;
7427 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
7428 PKT_VLAN_PRESENT_OFFSET());
7429 if (PKT_VLAN_PRESENT_BIT)
7430 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, PKT_VLAN_PRESENT_BIT);
7431 if (PKT_VLAN_PRESENT_BIT < 7)
7432 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
7433 break;
7434
7435 case offsetof(struct __sk_buff, vlan_tci):
7436 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
7437 bpf_target_off(struct sk_buff, vlan_tci, 2,
7438 target_size));
7439 break;
7440
7441 case offsetof(struct __sk_buff, cb[0]) ...
7442 offsetofend(struct __sk_buff, cb[4]) - 1:
7443 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20);
7444 BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
7445 offsetof(struct qdisc_skb_cb, data)) %
7446 sizeof(__u64));
7447
7448 prog->cb_access = 1;
7449 off = si->off;
7450 off -= offsetof(struct __sk_buff, cb[0]);
7451 off += offsetof(struct sk_buff, cb);
7452 off += offsetof(struct qdisc_skb_cb, data);
7453 if (type == BPF_WRITE)
7454 *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
7455 si->src_reg, off);
7456 else
7457 *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
7458 si->src_reg, off);
7459 break;
7460
7461 case offsetof(struct __sk_buff, tc_classid):
7462 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, tc_classid) != 2);
7463
7464 off = si->off;
7465 off -= offsetof(struct __sk_buff, tc_classid);
7466 off += offsetof(struct sk_buff, cb);
7467 off += offsetof(struct qdisc_skb_cb, tc_classid);
7468 *target_size = 2;
7469 if (type == BPF_WRITE)
7470 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg,
7471 si->src_reg, off);
7472 else
7473 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
7474 si->src_reg, off);
7475 break;
7476
7477 case offsetof(struct __sk_buff, data):
7478 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
7479 si->dst_reg, si->src_reg,
7480 offsetof(struct sk_buff, data));
7481 break;
7482
7483 case offsetof(struct __sk_buff, data_meta):
7484 off = si->off;
7485 off -= offsetof(struct __sk_buff, data_meta);
7486 off += offsetof(struct sk_buff, cb);
7487 off += offsetof(struct bpf_skb_data_end, data_meta);
7488 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
7489 si->src_reg, off);
7490 break;
7491
7492 case offsetof(struct __sk_buff, data_end):
7493 off = si->off;
7494 off -= offsetof(struct __sk_buff, data_end);
7495 off += offsetof(struct sk_buff, cb);
7496 off += offsetof(struct bpf_skb_data_end, data_end);
7497 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
7498 si->src_reg, off);
7499 break;
7500
7501 case offsetof(struct __sk_buff, tc_index):
7502 #ifdef CONFIG_NET_SCHED
7503 if (type == BPF_WRITE)
7504 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
7505 bpf_target_off(struct sk_buff, tc_index, 2,
7506 target_size));
7507 else
7508 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
7509 bpf_target_off(struct sk_buff, tc_index, 2,
7510 target_size));
7511 #else
7512 *target_size = 2;
7513 if (type == BPF_WRITE)
7514 *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
7515 else
7516 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
7517 #endif
7518 break;
7519
7520 case offsetof(struct __sk_buff, napi_id):
7521 #if defined(CONFIG_NET_RX_BUSY_POLL)
7522 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7523 bpf_target_off(struct sk_buff, napi_id, 4,
7524 target_size));
7525 *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
7526 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
7527 #else
7528 *target_size = 4;
7529 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
7530 #endif
7531 break;
7532 case offsetof(struct __sk_buff, family):
7533 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
7534
7535 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
7536 si->dst_reg, si->src_reg,
7537 offsetof(struct sk_buff, sk));
7538 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
7539 bpf_target_off(struct sock_common,
7540 skc_family,
7541 2, target_size));
7542 break;
7543 case offsetof(struct __sk_buff, remote_ip4):
7544 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
7545
7546 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
7547 si->dst_reg, si->src_reg,
7548 offsetof(struct sk_buff, sk));
7549 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
7550 bpf_target_off(struct sock_common,
7551 skc_daddr,
7552 4, target_size));
7553 break;
7554 case offsetof(struct __sk_buff, local_ip4):
7555 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
7556 skc_rcv_saddr) != 4);
7557
7558 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
7559 si->dst_reg, si->src_reg,
7560 offsetof(struct sk_buff, sk));
7561 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
7562 bpf_target_off(struct sock_common,
7563 skc_rcv_saddr,
7564 4, target_size));
7565 break;
7566 case offsetof(struct __sk_buff, remote_ip6[0]) ...
7567 offsetof(struct __sk_buff, remote_ip6[3]):
7568 #if IS_ENABLED(CONFIG_IPV6)
7569 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
7570 skc_v6_daddr.s6_addr32[0]) != 4);
7571
7572 off = si->off;
7573 off -= offsetof(struct __sk_buff, remote_ip6[0]);
7574
7575 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
7576 si->dst_reg, si->src_reg,
7577 offsetof(struct sk_buff, sk));
7578 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
7579 offsetof(struct sock_common,
7580 skc_v6_daddr.s6_addr32[0]) +
7581 off);
7582 #else
7583 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
7584 #endif
7585 break;
7586 case offsetof(struct __sk_buff, local_ip6[0]) ...
7587 offsetof(struct __sk_buff, local_ip6[3]):
7588 #if IS_ENABLED(CONFIG_IPV6)
7589 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
7590 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
7591
7592 off = si->off;
7593 off -= offsetof(struct __sk_buff, local_ip6[0]);
7594
7595 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
7596 si->dst_reg, si->src_reg,
7597 offsetof(struct sk_buff, sk));
7598 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
7599 offsetof(struct sock_common,
7600 skc_v6_rcv_saddr.s6_addr32[0]) +
7601 off);
7602 #else
7603 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
7604 #endif
7605 break;
7606
7607 case offsetof(struct __sk_buff, remote_port):
7608 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
7609
7610 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
7611 si->dst_reg, si->src_reg,
7612 offsetof(struct sk_buff, sk));
7613 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
7614 bpf_target_off(struct sock_common,
7615 skc_dport,
7616 2, target_size));
7617 #ifndef __BIG_ENDIAN_BITFIELD
7618 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
7619 #endif
7620 break;
7621
7622 case offsetof(struct __sk_buff, local_port):
7623 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
7624
7625 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
7626 si->dst_reg, si->src_reg,
7627 offsetof(struct sk_buff, sk));
7628 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
7629 bpf_target_off(struct sock_common,
7630 skc_num, 2, target_size));
7631 break;
7632
7633 case offsetof(struct __sk_buff, tstamp):
7634 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, tstamp) != 8);
7635
7636 if (type == BPF_WRITE)
7637 *insn++ = BPF_STX_MEM(BPF_DW,
7638 si->dst_reg, si->src_reg,
7639 bpf_target_off(struct sk_buff,
7640 tstamp, 8,
7641 target_size));
7642 else
7643 *insn++ = BPF_LDX_MEM(BPF_DW,
7644 si->dst_reg, si->src_reg,
7645 bpf_target_off(struct sk_buff,
7646 tstamp, 8,
7647 target_size));
7648 break;
7649
7650 case offsetof(struct __sk_buff, gso_segs):
7651 insn = bpf_convert_shinfo_access(si, insn);
7652 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_segs),
7653 si->dst_reg, si->dst_reg,
7654 bpf_target_off(struct skb_shared_info,
7655 gso_segs, 2,
7656 target_size));
7657 break;
7658 case offsetof(struct __sk_buff, gso_size):
7659 insn = bpf_convert_shinfo_access(si, insn);
7660 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_size),
7661 si->dst_reg, si->dst_reg,
7662 bpf_target_off(struct skb_shared_info,
7663 gso_size, 2,
7664 target_size));
7665 break;
7666 case offsetof(struct __sk_buff, wire_len):
7667 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, pkt_len) != 4);
7668
7669 off = si->off;
7670 off -= offsetof(struct __sk_buff, wire_len);
7671 off += offsetof(struct sk_buff, cb);
7672 off += offsetof(struct qdisc_skb_cb, pkt_len);
7673 *target_size = 4;
7674 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, off);
7675 break;
7676
7677 case offsetof(struct __sk_buff, sk):
7678 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
7679 si->dst_reg, si->src_reg,
7680 offsetof(struct sk_buff, sk));
7681 break;
7682 }
7683
7684 return insn - insn_buf;
7685 }
7686
bpf_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)7687 u32 bpf_sock_convert_ctx_access(enum bpf_access_type type,
7688 const struct bpf_insn *si,
7689 struct bpf_insn *insn_buf,
7690 struct bpf_prog *prog, u32 *target_size)
7691 {
7692 struct bpf_insn *insn = insn_buf;
7693 int off;
7694
7695 switch (si->off) {
7696 case offsetof(struct bpf_sock, bound_dev_if):
7697 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_bound_dev_if) != 4);
7698
7699 if (type == BPF_WRITE)
7700 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
7701 offsetof(struct sock, sk_bound_dev_if));
7702 else
7703 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7704 offsetof(struct sock, sk_bound_dev_if));
7705 break;
7706
7707 case offsetof(struct bpf_sock, mark):
7708 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_mark) != 4);
7709
7710 if (type == BPF_WRITE)
7711 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
7712 offsetof(struct sock, sk_mark));
7713 else
7714 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7715 offsetof(struct sock, sk_mark));
7716 break;
7717
7718 case offsetof(struct bpf_sock, priority):
7719 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_priority) != 4);
7720
7721 if (type == BPF_WRITE)
7722 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
7723 offsetof(struct sock, sk_priority));
7724 else
7725 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7726 offsetof(struct sock, sk_priority));
7727 break;
7728
7729 case offsetof(struct bpf_sock, family):
7730 *insn++ = BPF_LDX_MEM(
7731 BPF_FIELD_SIZEOF(struct sock_common, skc_family),
7732 si->dst_reg, si->src_reg,
7733 bpf_target_off(struct sock_common,
7734 skc_family,
7735 FIELD_SIZEOF(struct sock_common,
7736 skc_family),
7737 target_size));
7738 break;
7739
7740 case offsetof(struct bpf_sock, type):
7741 BUILD_BUG_ON(HWEIGHT32(SK_FL_TYPE_MASK) != BITS_PER_BYTE * 2);
7742 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7743 offsetof(struct sock, __sk_flags_offset));
7744 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK);
7745 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT);
7746 *target_size = 2;
7747 break;
7748
7749 case offsetof(struct bpf_sock, protocol):
7750 BUILD_BUG_ON(HWEIGHT32(SK_FL_PROTO_MASK) != BITS_PER_BYTE);
7751 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7752 offsetof(struct sock, __sk_flags_offset));
7753 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
7754 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_PROTO_SHIFT);
7755 *target_size = 1;
7756 break;
7757
7758 case offsetof(struct bpf_sock, src_ip4):
7759 *insn++ = BPF_LDX_MEM(
7760 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
7761 bpf_target_off(struct sock_common, skc_rcv_saddr,
7762 FIELD_SIZEOF(struct sock_common,
7763 skc_rcv_saddr),
7764 target_size));
7765 break;
7766
7767 case offsetof(struct bpf_sock, dst_ip4):
7768 *insn++ = BPF_LDX_MEM(
7769 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
7770 bpf_target_off(struct sock_common, skc_daddr,
7771 FIELD_SIZEOF(struct sock_common,
7772 skc_daddr),
7773 target_size));
7774 break;
7775
7776 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
7777 #if IS_ENABLED(CONFIG_IPV6)
7778 off = si->off;
7779 off -= offsetof(struct bpf_sock, src_ip6[0]);
7780 *insn++ = BPF_LDX_MEM(
7781 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
7782 bpf_target_off(
7783 struct sock_common,
7784 skc_v6_rcv_saddr.s6_addr32[0],
7785 FIELD_SIZEOF(struct sock_common,
7786 skc_v6_rcv_saddr.s6_addr32[0]),
7787 target_size) + off);
7788 #else
7789 (void)off;
7790 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
7791 #endif
7792 break;
7793
7794 case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
7795 #if IS_ENABLED(CONFIG_IPV6)
7796 off = si->off;
7797 off -= offsetof(struct bpf_sock, dst_ip6[0]);
7798 *insn++ = BPF_LDX_MEM(
7799 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
7800 bpf_target_off(struct sock_common,
7801 skc_v6_daddr.s6_addr32[0],
7802 FIELD_SIZEOF(struct sock_common,
7803 skc_v6_daddr.s6_addr32[0]),
7804 target_size) + off);
7805 #else
7806 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
7807 *target_size = 4;
7808 #endif
7809 break;
7810
7811 case offsetof(struct bpf_sock, src_port):
7812 *insn++ = BPF_LDX_MEM(
7813 BPF_FIELD_SIZEOF(struct sock_common, skc_num),
7814 si->dst_reg, si->src_reg,
7815 bpf_target_off(struct sock_common, skc_num,
7816 FIELD_SIZEOF(struct sock_common,
7817 skc_num),
7818 target_size));
7819 break;
7820
7821 case offsetof(struct bpf_sock, dst_port):
7822 *insn++ = BPF_LDX_MEM(
7823 BPF_FIELD_SIZEOF(struct sock_common, skc_dport),
7824 si->dst_reg, si->src_reg,
7825 bpf_target_off(struct sock_common, skc_dport,
7826 FIELD_SIZEOF(struct sock_common,
7827 skc_dport),
7828 target_size));
7829 break;
7830
7831 case offsetof(struct bpf_sock, state):
7832 *insn++ = BPF_LDX_MEM(
7833 BPF_FIELD_SIZEOF(struct sock_common, skc_state),
7834 si->dst_reg, si->src_reg,
7835 bpf_target_off(struct sock_common, skc_state,
7836 FIELD_SIZEOF(struct sock_common,
7837 skc_state),
7838 target_size));
7839 break;
7840 }
7841
7842 return insn - insn_buf;
7843 }
7844
tc_cls_act_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)7845 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
7846 const struct bpf_insn *si,
7847 struct bpf_insn *insn_buf,
7848 struct bpf_prog *prog, u32 *target_size)
7849 {
7850 struct bpf_insn *insn = insn_buf;
7851
7852 switch (si->off) {
7853 case offsetof(struct __sk_buff, ifindex):
7854 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
7855 si->dst_reg, si->src_reg,
7856 offsetof(struct sk_buff, dev));
7857 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
7858 bpf_target_off(struct net_device, ifindex, 4,
7859 target_size));
7860 break;
7861 default:
7862 return bpf_convert_ctx_access(type, si, insn_buf, prog,
7863 target_size);
7864 }
7865
7866 return insn - insn_buf;
7867 }
7868
xdp_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)7869 static u32 xdp_convert_ctx_access(enum bpf_access_type type,
7870 const struct bpf_insn *si,
7871 struct bpf_insn *insn_buf,
7872 struct bpf_prog *prog, u32 *target_size)
7873 {
7874 struct bpf_insn *insn = insn_buf;
7875
7876 switch (si->off) {
7877 case offsetof(struct xdp_md, data):
7878 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
7879 si->dst_reg, si->src_reg,
7880 offsetof(struct xdp_buff, data));
7881 break;
7882 case offsetof(struct xdp_md, data_meta):
7883 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
7884 si->dst_reg, si->src_reg,
7885 offsetof(struct xdp_buff, data_meta));
7886 break;
7887 case offsetof(struct xdp_md, data_end):
7888 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
7889 si->dst_reg, si->src_reg,
7890 offsetof(struct xdp_buff, data_end));
7891 break;
7892 case offsetof(struct xdp_md, ingress_ifindex):
7893 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
7894 si->dst_reg, si->src_reg,
7895 offsetof(struct xdp_buff, rxq));
7896 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev),
7897 si->dst_reg, si->dst_reg,
7898 offsetof(struct xdp_rxq_info, dev));
7899 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
7900 offsetof(struct net_device, ifindex));
7901 break;
7902 case offsetof(struct xdp_md, rx_queue_index):
7903 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
7904 si->dst_reg, si->src_reg,
7905 offsetof(struct xdp_buff, rxq));
7906 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
7907 offsetof(struct xdp_rxq_info,
7908 queue_index));
7909 break;
7910 }
7911
7912 return insn - insn_buf;
7913 }
7914
7915 /* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of
7916 * context Structure, F is Field in context structure that contains a pointer
7917 * to Nested Structure of type NS that has the field NF.
7918 *
7919 * SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make
7920 * sure that SIZE is not greater than actual size of S.F.NF.
7921 *
7922 * If offset OFF is provided, the load happens from that offset relative to
7923 * offset of NF.
7924 */
7925 #define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF) \
7926 do { \
7927 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg, \
7928 si->src_reg, offsetof(S, F)); \
7929 *insn++ = BPF_LDX_MEM( \
7930 SIZE, si->dst_reg, si->dst_reg, \
7931 bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF), \
7932 target_size) \
7933 + OFF); \
7934 } while (0)
7935
7936 #define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF) \
7937 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, \
7938 BPF_FIELD_SIZEOF(NS, NF), 0)
7939
7940 /* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to
7941 * SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation.
7942 *
7943 * In addition it uses Temporary Field TF (member of struct S) as the 3rd
7944 * "register" since two registers available in convert_ctx_access are not
7945 * enough: we can't override neither SRC, since it contains value to store, nor
7946 * DST since it contains pointer to context that may be used by later
7947 * instructions. But we need a temporary place to save pointer to nested
7948 * structure whose field we want to store to.
7949 */
7950 #define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE, OFF, TF) \
7951 do { \
7952 int tmp_reg = BPF_REG_9; \
7953 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \
7954 --tmp_reg; \
7955 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \
7956 --tmp_reg; \
7957 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg, \
7958 offsetof(S, TF)); \
7959 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg, \
7960 si->dst_reg, offsetof(S, F)); \
7961 *insn++ = BPF_STX_MEM(SIZE, tmp_reg, si->src_reg, \
7962 bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF), \
7963 target_size) \
7964 + OFF); \
7965 *insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg, \
7966 offsetof(S, TF)); \
7967 } while (0)
7968
7969 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \
7970 TF) \
7971 do { \
7972 if (type == BPF_WRITE) { \
7973 SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE, \
7974 OFF, TF); \
7975 } else { \
7976 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( \
7977 S, NS, F, NF, SIZE, OFF); \
7978 } \
7979 } while (0)
7980
7981 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(S, NS, F, NF, TF) \
7982 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( \
7983 S, NS, F, NF, BPF_FIELD_SIZEOF(NS, NF), 0, TF)
7984
sock_addr_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)7985 static u32 sock_addr_convert_ctx_access(enum bpf_access_type type,
7986 const struct bpf_insn *si,
7987 struct bpf_insn *insn_buf,
7988 struct bpf_prog *prog, u32 *target_size)
7989 {
7990 struct bpf_insn *insn = insn_buf;
7991 int off;
7992
7993 switch (si->off) {
7994 case offsetof(struct bpf_sock_addr, user_family):
7995 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
7996 struct sockaddr, uaddr, sa_family);
7997 break;
7998
7999 case offsetof(struct bpf_sock_addr, user_ip4):
8000 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
8001 struct bpf_sock_addr_kern, struct sockaddr_in, uaddr,
8002 sin_addr, BPF_SIZE(si->code), 0, tmp_reg);
8003 break;
8004
8005 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
8006 off = si->off;
8007 off -= offsetof(struct bpf_sock_addr, user_ip6[0]);
8008 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
8009 struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
8010 sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off,
8011 tmp_reg);
8012 break;
8013
8014 case offsetof(struct bpf_sock_addr, user_port):
8015 /* To get port we need to know sa_family first and then treat
8016 * sockaddr as either sockaddr_in or sockaddr_in6.
8017 * Though we can simplify since port field has same offset and
8018 * size in both structures.
8019 * Here we check this invariant and use just one of the
8020 * structures if it's true.
8021 */
8022 BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) !=
8023 offsetof(struct sockaddr_in6, sin6_port));
8024 BUILD_BUG_ON(FIELD_SIZEOF(struct sockaddr_in, sin_port) !=
8025 FIELD_SIZEOF(struct sockaddr_in6, sin6_port));
8026 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(struct bpf_sock_addr_kern,
8027 struct sockaddr_in6, uaddr,
8028 sin6_port, tmp_reg);
8029 break;
8030
8031 case offsetof(struct bpf_sock_addr, family):
8032 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
8033 struct sock, sk, sk_family);
8034 break;
8035
8036 case offsetof(struct bpf_sock_addr, type):
8037 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(
8038 struct bpf_sock_addr_kern, struct sock, sk,
8039 __sk_flags_offset, BPF_W, 0);
8040 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK);
8041 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT);
8042 break;
8043
8044 case offsetof(struct bpf_sock_addr, protocol):
8045 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(
8046 struct bpf_sock_addr_kern, struct sock, sk,
8047 __sk_flags_offset, BPF_W, 0);
8048 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
8049 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg,
8050 SK_FL_PROTO_SHIFT);
8051 break;
8052
8053 case offsetof(struct bpf_sock_addr, msg_src_ip4):
8054 /* Treat t_ctx as struct in_addr for msg_src_ip4. */
8055 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
8056 struct bpf_sock_addr_kern, struct in_addr, t_ctx,
8057 s_addr, BPF_SIZE(si->code), 0, tmp_reg);
8058 break;
8059
8060 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
8061 msg_src_ip6[3]):
8062 off = si->off;
8063 off -= offsetof(struct bpf_sock_addr, msg_src_ip6[0]);
8064 /* Treat t_ctx as struct in6_addr for msg_src_ip6. */
8065 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
8066 struct bpf_sock_addr_kern, struct in6_addr, t_ctx,
8067 s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg);
8068 break;
8069 case offsetof(struct bpf_sock_addr, sk):
8070 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_addr_kern, sk),
8071 si->dst_reg, si->src_reg,
8072 offsetof(struct bpf_sock_addr_kern, sk));
8073 break;
8074 }
8075
8076 return insn - insn_buf;
8077 }
8078
sock_ops_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)8079 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
8080 const struct bpf_insn *si,
8081 struct bpf_insn *insn_buf,
8082 struct bpf_prog *prog,
8083 u32 *target_size)
8084 {
8085 struct bpf_insn *insn = insn_buf;
8086 int off;
8087
8088 /* Helper macro for adding read access to tcp_sock or sock fields. */
8089 #define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \
8090 do { \
8091 BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) > \
8092 FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD)); \
8093 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
8094 struct bpf_sock_ops_kern, \
8095 is_fullsock), \
8096 si->dst_reg, si->src_reg, \
8097 offsetof(struct bpf_sock_ops_kern, \
8098 is_fullsock)); \
8099 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 2); \
8100 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
8101 struct bpf_sock_ops_kern, sk),\
8102 si->dst_reg, si->src_reg, \
8103 offsetof(struct bpf_sock_ops_kern, sk));\
8104 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ, \
8105 OBJ_FIELD), \
8106 si->dst_reg, si->dst_reg, \
8107 offsetof(OBJ, OBJ_FIELD)); \
8108 } while (0)
8109
8110 #define SOCK_OPS_GET_SK() \
8111 do { \
8112 int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 1; \
8113 if (si->dst_reg == reg || si->src_reg == reg) \
8114 reg--; \
8115 if (si->dst_reg == reg || si->src_reg == reg) \
8116 reg--; \
8117 if (si->dst_reg == si->src_reg) { \
8118 *insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg, \
8119 offsetof(struct bpf_sock_ops_kern, \
8120 temp)); \
8121 fullsock_reg = reg; \
8122 jmp += 2; \
8123 } \
8124 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
8125 struct bpf_sock_ops_kern, \
8126 is_fullsock), \
8127 fullsock_reg, si->src_reg, \
8128 offsetof(struct bpf_sock_ops_kern, \
8129 is_fullsock)); \
8130 *insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp); \
8131 if (si->dst_reg == si->src_reg) \
8132 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg, \
8133 offsetof(struct bpf_sock_ops_kern, \
8134 temp)); \
8135 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
8136 struct bpf_sock_ops_kern, sk),\
8137 si->dst_reg, si->src_reg, \
8138 offsetof(struct bpf_sock_ops_kern, sk));\
8139 if (si->dst_reg == si->src_reg) { \
8140 *insn++ = BPF_JMP_A(1); \
8141 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg, \
8142 offsetof(struct bpf_sock_ops_kern, \
8143 temp)); \
8144 } \
8145 } while (0)
8146
8147 #define SOCK_OPS_GET_TCP_SOCK_FIELD(FIELD) \
8148 SOCK_OPS_GET_FIELD(FIELD, FIELD, struct tcp_sock)
8149
8150 /* Helper macro for adding write access to tcp_sock or sock fields.
8151 * The macro is called with two registers, dst_reg which contains a pointer
8152 * to ctx (context) and src_reg which contains the value that should be
8153 * stored. However, we need an additional register since we cannot overwrite
8154 * dst_reg because it may be used later in the program.
8155 * Instead we "borrow" one of the other register. We first save its value
8156 * into a new (temp) field in bpf_sock_ops_kern, use it, and then restore
8157 * it at the end of the macro.
8158 */
8159 #define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \
8160 do { \
8161 int reg = BPF_REG_9; \
8162 BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) > \
8163 FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD)); \
8164 if (si->dst_reg == reg || si->src_reg == reg) \
8165 reg--; \
8166 if (si->dst_reg == reg || si->src_reg == reg) \
8167 reg--; \
8168 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg, \
8169 offsetof(struct bpf_sock_ops_kern, \
8170 temp)); \
8171 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
8172 struct bpf_sock_ops_kern, \
8173 is_fullsock), \
8174 reg, si->dst_reg, \
8175 offsetof(struct bpf_sock_ops_kern, \
8176 is_fullsock)); \
8177 *insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2); \
8178 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
8179 struct bpf_sock_ops_kern, sk),\
8180 reg, si->dst_reg, \
8181 offsetof(struct bpf_sock_ops_kern, sk));\
8182 *insn++ = BPF_STX_MEM(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD), \
8183 reg, si->src_reg, \
8184 offsetof(OBJ, OBJ_FIELD)); \
8185 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg, \
8186 offsetof(struct bpf_sock_ops_kern, \
8187 temp)); \
8188 } while (0)
8189
8190 #define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE) \
8191 do { \
8192 if (TYPE == BPF_WRITE) \
8193 SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \
8194 else \
8195 SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \
8196 } while (0)
8197
8198 if (insn > insn_buf)
8199 return insn - insn_buf;
8200
8201 switch (si->off) {
8202 case offsetof(struct bpf_sock_ops, op) ...
8203 offsetof(struct bpf_sock_ops, replylong[3]):
8204 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, op) !=
8205 FIELD_SIZEOF(struct bpf_sock_ops_kern, op));
8206 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, reply) !=
8207 FIELD_SIZEOF(struct bpf_sock_ops_kern, reply));
8208 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, replylong) !=
8209 FIELD_SIZEOF(struct bpf_sock_ops_kern, replylong));
8210 off = si->off;
8211 off -= offsetof(struct bpf_sock_ops, op);
8212 off += offsetof(struct bpf_sock_ops_kern, op);
8213 if (type == BPF_WRITE)
8214 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
8215 off);
8216 else
8217 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
8218 off);
8219 break;
8220
8221 case offsetof(struct bpf_sock_ops, family):
8222 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
8223
8224 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8225 struct bpf_sock_ops_kern, sk),
8226 si->dst_reg, si->src_reg,
8227 offsetof(struct bpf_sock_ops_kern, sk));
8228 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
8229 offsetof(struct sock_common, skc_family));
8230 break;
8231
8232 case offsetof(struct bpf_sock_ops, remote_ip4):
8233 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
8234
8235 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8236 struct bpf_sock_ops_kern, sk),
8237 si->dst_reg, si->src_reg,
8238 offsetof(struct bpf_sock_ops_kern, sk));
8239 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8240 offsetof(struct sock_common, skc_daddr));
8241 break;
8242
8243 case offsetof(struct bpf_sock_ops, local_ip4):
8244 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
8245 skc_rcv_saddr) != 4);
8246
8247 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8248 struct bpf_sock_ops_kern, sk),
8249 si->dst_reg, si->src_reg,
8250 offsetof(struct bpf_sock_ops_kern, sk));
8251 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8252 offsetof(struct sock_common,
8253 skc_rcv_saddr));
8254 break;
8255
8256 case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
8257 offsetof(struct bpf_sock_ops, remote_ip6[3]):
8258 #if IS_ENABLED(CONFIG_IPV6)
8259 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
8260 skc_v6_daddr.s6_addr32[0]) != 4);
8261
8262 off = si->off;
8263 off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
8264 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8265 struct bpf_sock_ops_kern, sk),
8266 si->dst_reg, si->src_reg,
8267 offsetof(struct bpf_sock_ops_kern, sk));
8268 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8269 offsetof(struct sock_common,
8270 skc_v6_daddr.s6_addr32[0]) +
8271 off);
8272 #else
8273 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
8274 #endif
8275 break;
8276
8277 case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
8278 offsetof(struct bpf_sock_ops, local_ip6[3]):
8279 #if IS_ENABLED(CONFIG_IPV6)
8280 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
8281 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
8282
8283 off = si->off;
8284 off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
8285 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8286 struct bpf_sock_ops_kern, sk),
8287 si->dst_reg, si->src_reg,
8288 offsetof(struct bpf_sock_ops_kern, sk));
8289 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8290 offsetof(struct sock_common,
8291 skc_v6_rcv_saddr.s6_addr32[0]) +
8292 off);
8293 #else
8294 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
8295 #endif
8296 break;
8297
8298 case offsetof(struct bpf_sock_ops, remote_port):
8299 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
8300
8301 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8302 struct bpf_sock_ops_kern, sk),
8303 si->dst_reg, si->src_reg,
8304 offsetof(struct bpf_sock_ops_kern, sk));
8305 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
8306 offsetof(struct sock_common, skc_dport));
8307 #ifndef __BIG_ENDIAN_BITFIELD
8308 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
8309 #endif
8310 break;
8311
8312 case offsetof(struct bpf_sock_ops, local_port):
8313 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
8314
8315 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8316 struct bpf_sock_ops_kern, sk),
8317 si->dst_reg, si->src_reg,
8318 offsetof(struct bpf_sock_ops_kern, sk));
8319 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
8320 offsetof(struct sock_common, skc_num));
8321 break;
8322
8323 case offsetof(struct bpf_sock_ops, is_fullsock):
8324 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8325 struct bpf_sock_ops_kern,
8326 is_fullsock),
8327 si->dst_reg, si->src_reg,
8328 offsetof(struct bpf_sock_ops_kern,
8329 is_fullsock));
8330 break;
8331
8332 case offsetof(struct bpf_sock_ops, state):
8333 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_state) != 1);
8334
8335 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8336 struct bpf_sock_ops_kern, sk),
8337 si->dst_reg, si->src_reg,
8338 offsetof(struct bpf_sock_ops_kern, sk));
8339 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg,
8340 offsetof(struct sock_common, skc_state));
8341 break;
8342
8343 case offsetof(struct bpf_sock_ops, rtt_min):
8344 BUILD_BUG_ON(FIELD_SIZEOF(struct tcp_sock, rtt_min) !=
8345 sizeof(struct minmax));
8346 BUILD_BUG_ON(sizeof(struct minmax) <
8347 sizeof(struct minmax_sample));
8348
8349 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8350 struct bpf_sock_ops_kern, sk),
8351 si->dst_reg, si->src_reg,
8352 offsetof(struct bpf_sock_ops_kern, sk));
8353 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8354 offsetof(struct tcp_sock, rtt_min) +
8355 FIELD_SIZEOF(struct minmax_sample, t));
8356 break;
8357
8358 case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags):
8359 SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags,
8360 struct tcp_sock);
8361 break;
8362
8363 case offsetof(struct bpf_sock_ops, sk_txhash):
8364 SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash,
8365 struct sock, type);
8366 break;
8367 case offsetof(struct bpf_sock_ops, snd_cwnd):
8368 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_cwnd);
8369 break;
8370 case offsetof(struct bpf_sock_ops, srtt_us):
8371 SOCK_OPS_GET_TCP_SOCK_FIELD(srtt_us);
8372 break;
8373 case offsetof(struct bpf_sock_ops, snd_ssthresh):
8374 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_ssthresh);
8375 break;
8376 case offsetof(struct bpf_sock_ops, rcv_nxt):
8377 SOCK_OPS_GET_TCP_SOCK_FIELD(rcv_nxt);
8378 break;
8379 case offsetof(struct bpf_sock_ops, snd_nxt):
8380 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_nxt);
8381 break;
8382 case offsetof(struct bpf_sock_ops, snd_una):
8383 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_una);
8384 break;
8385 case offsetof(struct bpf_sock_ops, mss_cache):
8386 SOCK_OPS_GET_TCP_SOCK_FIELD(mss_cache);
8387 break;
8388 case offsetof(struct bpf_sock_ops, ecn_flags):
8389 SOCK_OPS_GET_TCP_SOCK_FIELD(ecn_flags);
8390 break;
8391 case offsetof(struct bpf_sock_ops, rate_delivered):
8392 SOCK_OPS_GET_TCP_SOCK_FIELD(rate_delivered);
8393 break;
8394 case offsetof(struct bpf_sock_ops, rate_interval_us):
8395 SOCK_OPS_GET_TCP_SOCK_FIELD(rate_interval_us);
8396 break;
8397 case offsetof(struct bpf_sock_ops, packets_out):
8398 SOCK_OPS_GET_TCP_SOCK_FIELD(packets_out);
8399 break;
8400 case offsetof(struct bpf_sock_ops, retrans_out):
8401 SOCK_OPS_GET_TCP_SOCK_FIELD(retrans_out);
8402 break;
8403 case offsetof(struct bpf_sock_ops, total_retrans):
8404 SOCK_OPS_GET_TCP_SOCK_FIELD(total_retrans);
8405 break;
8406 case offsetof(struct bpf_sock_ops, segs_in):
8407 SOCK_OPS_GET_TCP_SOCK_FIELD(segs_in);
8408 break;
8409 case offsetof(struct bpf_sock_ops, data_segs_in):
8410 SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_in);
8411 break;
8412 case offsetof(struct bpf_sock_ops, segs_out):
8413 SOCK_OPS_GET_TCP_SOCK_FIELD(segs_out);
8414 break;
8415 case offsetof(struct bpf_sock_ops, data_segs_out):
8416 SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_out);
8417 break;
8418 case offsetof(struct bpf_sock_ops, lost_out):
8419 SOCK_OPS_GET_TCP_SOCK_FIELD(lost_out);
8420 break;
8421 case offsetof(struct bpf_sock_ops, sacked_out):
8422 SOCK_OPS_GET_TCP_SOCK_FIELD(sacked_out);
8423 break;
8424 case offsetof(struct bpf_sock_ops, bytes_received):
8425 SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_received);
8426 break;
8427 case offsetof(struct bpf_sock_ops, bytes_acked):
8428 SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_acked);
8429 break;
8430 case offsetof(struct bpf_sock_ops, sk):
8431 SOCK_OPS_GET_SK();
8432 break;
8433 }
8434 return insn - insn_buf;
8435 }
8436
sk_skb_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)8437 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
8438 const struct bpf_insn *si,
8439 struct bpf_insn *insn_buf,
8440 struct bpf_prog *prog, u32 *target_size)
8441 {
8442 struct bpf_insn *insn = insn_buf;
8443 int off;
8444
8445 switch (si->off) {
8446 case offsetof(struct __sk_buff, data_end):
8447 off = si->off;
8448 off -= offsetof(struct __sk_buff, data_end);
8449 off += offsetof(struct sk_buff, cb);
8450 off += offsetof(struct tcp_skb_cb, bpf.data_end);
8451 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
8452 si->src_reg, off);
8453 break;
8454 case offsetof(struct __sk_buff, cb[0]) ...
8455 offsetofend(struct __sk_buff, cb[4]) - 1:
8456 BUILD_BUG_ON(sizeof_field(struct sk_skb_cb, data) < 20);
8457 BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
8458 offsetof(struct sk_skb_cb, data)) %
8459 sizeof(__u64));
8460
8461 prog->cb_access = 1;
8462 off = si->off;
8463 off -= offsetof(struct __sk_buff, cb[0]);
8464 off += offsetof(struct sk_buff, cb);
8465 off += offsetof(struct sk_skb_cb, data);
8466 if (type == BPF_WRITE)
8467 *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
8468 si->src_reg, off);
8469 else
8470 *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
8471 si->src_reg, off);
8472 break;
8473
8474
8475 default:
8476 return bpf_convert_ctx_access(type, si, insn_buf, prog,
8477 target_size);
8478 }
8479
8480 return insn - insn_buf;
8481 }
8482
sk_msg_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)8483 static u32 sk_msg_convert_ctx_access(enum bpf_access_type type,
8484 const struct bpf_insn *si,
8485 struct bpf_insn *insn_buf,
8486 struct bpf_prog *prog, u32 *target_size)
8487 {
8488 struct bpf_insn *insn = insn_buf;
8489 #if IS_ENABLED(CONFIG_IPV6)
8490 int off;
8491 #endif
8492
8493 /* convert ctx uses the fact sg element is first in struct */
8494 BUILD_BUG_ON(offsetof(struct sk_msg, sg) != 0);
8495
8496 switch (si->off) {
8497 case offsetof(struct sk_msg_md, data):
8498 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data),
8499 si->dst_reg, si->src_reg,
8500 offsetof(struct sk_msg, data));
8501 break;
8502 case offsetof(struct sk_msg_md, data_end):
8503 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data_end),
8504 si->dst_reg, si->src_reg,
8505 offsetof(struct sk_msg, data_end));
8506 break;
8507 case offsetof(struct sk_msg_md, family):
8508 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
8509
8510 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8511 struct sk_msg, sk),
8512 si->dst_reg, si->src_reg,
8513 offsetof(struct sk_msg, sk));
8514 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
8515 offsetof(struct sock_common, skc_family));
8516 break;
8517
8518 case offsetof(struct sk_msg_md, remote_ip4):
8519 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
8520
8521 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8522 struct sk_msg, sk),
8523 si->dst_reg, si->src_reg,
8524 offsetof(struct sk_msg, sk));
8525 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8526 offsetof(struct sock_common, skc_daddr));
8527 break;
8528
8529 case offsetof(struct sk_msg_md, local_ip4):
8530 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
8531 skc_rcv_saddr) != 4);
8532
8533 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8534 struct sk_msg, sk),
8535 si->dst_reg, si->src_reg,
8536 offsetof(struct sk_msg, sk));
8537 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8538 offsetof(struct sock_common,
8539 skc_rcv_saddr));
8540 break;
8541
8542 case offsetof(struct sk_msg_md, remote_ip6[0]) ...
8543 offsetof(struct sk_msg_md, remote_ip6[3]):
8544 #if IS_ENABLED(CONFIG_IPV6)
8545 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
8546 skc_v6_daddr.s6_addr32[0]) != 4);
8547
8548 off = si->off;
8549 off -= offsetof(struct sk_msg_md, remote_ip6[0]);
8550 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8551 struct sk_msg, sk),
8552 si->dst_reg, si->src_reg,
8553 offsetof(struct sk_msg, sk));
8554 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8555 offsetof(struct sock_common,
8556 skc_v6_daddr.s6_addr32[0]) +
8557 off);
8558 #else
8559 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
8560 #endif
8561 break;
8562
8563 case offsetof(struct sk_msg_md, local_ip6[0]) ...
8564 offsetof(struct sk_msg_md, local_ip6[3]):
8565 #if IS_ENABLED(CONFIG_IPV6)
8566 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
8567 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
8568
8569 off = si->off;
8570 off -= offsetof(struct sk_msg_md, local_ip6[0]);
8571 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8572 struct sk_msg, sk),
8573 si->dst_reg, si->src_reg,
8574 offsetof(struct sk_msg, sk));
8575 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8576 offsetof(struct sock_common,
8577 skc_v6_rcv_saddr.s6_addr32[0]) +
8578 off);
8579 #else
8580 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
8581 #endif
8582 break;
8583
8584 case offsetof(struct sk_msg_md, remote_port):
8585 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
8586
8587 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8588 struct sk_msg, sk),
8589 si->dst_reg, si->src_reg,
8590 offsetof(struct sk_msg, sk));
8591 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
8592 offsetof(struct sock_common, skc_dport));
8593 #ifndef __BIG_ENDIAN_BITFIELD
8594 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
8595 #endif
8596 break;
8597
8598 case offsetof(struct sk_msg_md, local_port):
8599 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
8600
8601 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
8602 struct sk_msg, sk),
8603 si->dst_reg, si->src_reg,
8604 offsetof(struct sk_msg, sk));
8605 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
8606 offsetof(struct sock_common, skc_num));
8607 break;
8608
8609 case offsetof(struct sk_msg_md, size):
8610 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_sg, size),
8611 si->dst_reg, si->src_reg,
8612 offsetof(struct sk_msg_sg, size));
8613 break;
8614 }
8615
8616 return insn - insn_buf;
8617 }
8618
8619 const struct bpf_verifier_ops sk_filter_verifier_ops = {
8620 .get_func_proto = sk_filter_func_proto,
8621 .is_valid_access = sk_filter_is_valid_access,
8622 .convert_ctx_access = bpf_convert_ctx_access,
8623 .gen_ld_abs = bpf_gen_ld_abs,
8624 };
8625
8626 const struct bpf_prog_ops sk_filter_prog_ops = {
8627 .test_run = bpf_prog_test_run_skb,
8628 };
8629
8630 const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
8631 .get_func_proto = tc_cls_act_func_proto,
8632 .is_valid_access = tc_cls_act_is_valid_access,
8633 .convert_ctx_access = tc_cls_act_convert_ctx_access,
8634 .gen_prologue = tc_cls_act_prologue,
8635 .gen_ld_abs = bpf_gen_ld_abs,
8636 };
8637
8638 const struct bpf_prog_ops tc_cls_act_prog_ops = {
8639 .test_run = bpf_prog_test_run_skb,
8640 };
8641
8642 const struct bpf_verifier_ops xdp_verifier_ops = {
8643 .get_func_proto = xdp_func_proto,
8644 .is_valid_access = xdp_is_valid_access,
8645 .convert_ctx_access = xdp_convert_ctx_access,
8646 .gen_prologue = bpf_noop_prologue,
8647 };
8648
8649 const struct bpf_prog_ops xdp_prog_ops = {
8650 .test_run = bpf_prog_test_run_xdp,
8651 };
8652
8653 const struct bpf_verifier_ops cg_skb_verifier_ops = {
8654 .get_func_proto = cg_skb_func_proto,
8655 .is_valid_access = cg_skb_is_valid_access,
8656 .convert_ctx_access = bpf_convert_ctx_access,
8657 };
8658
8659 const struct bpf_prog_ops cg_skb_prog_ops = {
8660 .test_run = bpf_prog_test_run_skb,
8661 };
8662
8663 const struct bpf_verifier_ops lwt_in_verifier_ops = {
8664 .get_func_proto = lwt_in_func_proto,
8665 .is_valid_access = lwt_is_valid_access,
8666 .convert_ctx_access = bpf_convert_ctx_access,
8667 };
8668
8669 const struct bpf_prog_ops lwt_in_prog_ops = {
8670 .test_run = bpf_prog_test_run_skb,
8671 };
8672
8673 const struct bpf_verifier_ops lwt_out_verifier_ops = {
8674 .get_func_proto = lwt_out_func_proto,
8675 .is_valid_access = lwt_is_valid_access,
8676 .convert_ctx_access = bpf_convert_ctx_access,
8677 };
8678
8679 const struct bpf_prog_ops lwt_out_prog_ops = {
8680 .test_run = bpf_prog_test_run_skb,
8681 };
8682
8683 const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
8684 .get_func_proto = lwt_xmit_func_proto,
8685 .is_valid_access = lwt_is_valid_access,
8686 .convert_ctx_access = bpf_convert_ctx_access,
8687 .gen_prologue = tc_cls_act_prologue,
8688 };
8689
8690 const struct bpf_prog_ops lwt_xmit_prog_ops = {
8691 .test_run = bpf_prog_test_run_skb,
8692 };
8693
8694 const struct bpf_verifier_ops lwt_seg6local_verifier_ops = {
8695 .get_func_proto = lwt_seg6local_func_proto,
8696 .is_valid_access = lwt_is_valid_access,
8697 .convert_ctx_access = bpf_convert_ctx_access,
8698 };
8699
8700 const struct bpf_prog_ops lwt_seg6local_prog_ops = {
8701 .test_run = bpf_prog_test_run_skb,
8702 };
8703
8704 const struct bpf_verifier_ops cg_sock_verifier_ops = {
8705 .get_func_proto = sock_filter_func_proto,
8706 .is_valid_access = sock_filter_is_valid_access,
8707 .convert_ctx_access = bpf_sock_convert_ctx_access,
8708 };
8709
8710 const struct bpf_prog_ops cg_sock_prog_ops = {
8711 };
8712
8713 const struct bpf_verifier_ops cg_sock_addr_verifier_ops = {
8714 .get_func_proto = sock_addr_func_proto,
8715 .is_valid_access = sock_addr_is_valid_access,
8716 .convert_ctx_access = sock_addr_convert_ctx_access,
8717 };
8718
8719 const struct bpf_prog_ops cg_sock_addr_prog_ops = {
8720 };
8721
8722 const struct bpf_verifier_ops sock_ops_verifier_ops = {
8723 .get_func_proto = sock_ops_func_proto,
8724 .is_valid_access = sock_ops_is_valid_access,
8725 .convert_ctx_access = sock_ops_convert_ctx_access,
8726 };
8727
8728 const struct bpf_prog_ops sock_ops_prog_ops = {
8729 };
8730
8731 const struct bpf_verifier_ops sk_skb_verifier_ops = {
8732 .get_func_proto = sk_skb_func_proto,
8733 .is_valid_access = sk_skb_is_valid_access,
8734 .convert_ctx_access = sk_skb_convert_ctx_access,
8735 .gen_prologue = sk_skb_prologue,
8736 };
8737
8738 const struct bpf_prog_ops sk_skb_prog_ops = {
8739 };
8740
8741 const struct bpf_verifier_ops sk_msg_verifier_ops = {
8742 .get_func_proto = sk_msg_func_proto,
8743 .is_valid_access = sk_msg_is_valid_access,
8744 .convert_ctx_access = sk_msg_convert_ctx_access,
8745 .gen_prologue = bpf_noop_prologue,
8746 };
8747
8748 const struct bpf_prog_ops sk_msg_prog_ops = {
8749 };
8750
8751 const struct bpf_verifier_ops flow_dissector_verifier_ops = {
8752 .get_func_proto = flow_dissector_func_proto,
8753 .is_valid_access = flow_dissector_is_valid_access,
8754 .convert_ctx_access = flow_dissector_convert_ctx_access,
8755 };
8756
8757 const struct bpf_prog_ops flow_dissector_prog_ops = {
8758 .test_run = bpf_prog_test_run_flow_dissector,
8759 };
8760
sk_detach_filter(struct sock * sk)8761 int sk_detach_filter(struct sock *sk)
8762 {
8763 int ret = -ENOENT;
8764 struct sk_filter *filter;
8765
8766 if (sock_flag(sk, SOCK_FILTER_LOCKED))
8767 return -EPERM;
8768
8769 filter = rcu_dereference_protected(sk->sk_filter,
8770 lockdep_sock_is_held(sk));
8771 if (filter) {
8772 RCU_INIT_POINTER(sk->sk_filter, NULL);
8773 sk_filter_uncharge(sk, filter);
8774 ret = 0;
8775 }
8776
8777 return ret;
8778 }
8779 EXPORT_SYMBOL_GPL(sk_detach_filter);
8780
sk_get_filter(struct sock * sk,struct sock_filter __user * ubuf,unsigned int len)8781 int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf,
8782 unsigned int len)
8783 {
8784 struct sock_fprog_kern *fprog;
8785 struct sk_filter *filter;
8786 int ret = 0;
8787
8788 lock_sock(sk);
8789 filter = rcu_dereference_protected(sk->sk_filter,
8790 lockdep_sock_is_held(sk));
8791 if (!filter)
8792 goto out;
8793
8794 /* We're copying the filter that has been originally attached,
8795 * so no conversion/decode needed anymore. eBPF programs that
8796 * have no original program cannot be dumped through this.
8797 */
8798 ret = -EACCES;
8799 fprog = filter->prog->orig_prog;
8800 if (!fprog)
8801 goto out;
8802
8803 ret = fprog->len;
8804 if (!len)
8805 /* User space only enquires number of filter blocks. */
8806 goto out;
8807
8808 ret = -EINVAL;
8809 if (len < fprog->len)
8810 goto out;
8811
8812 ret = -EFAULT;
8813 if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog)))
8814 goto out;
8815
8816 /* Instead of bytes, the API requests to return the number
8817 * of filter blocks.
8818 */
8819 ret = fprog->len;
8820 out:
8821 release_sock(sk);
8822 return ret;
8823 }
8824
8825 #ifdef CONFIG_INET
8826 struct sk_reuseport_kern {
8827 struct sk_buff *skb;
8828 struct sock *sk;
8829 struct sock *selected_sk;
8830 void *data_end;
8831 u32 hash;
8832 u32 reuseport_id;
8833 bool bind_inany;
8834 };
8835
bpf_init_reuseport_kern(struct sk_reuseport_kern * reuse_kern,struct sock_reuseport * reuse,struct sock * sk,struct sk_buff * skb,u32 hash)8836 static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern,
8837 struct sock_reuseport *reuse,
8838 struct sock *sk, struct sk_buff *skb,
8839 u32 hash)
8840 {
8841 reuse_kern->skb = skb;
8842 reuse_kern->sk = sk;
8843 reuse_kern->selected_sk = NULL;
8844 reuse_kern->data_end = skb->data + skb_headlen(skb);
8845 reuse_kern->hash = hash;
8846 reuse_kern->reuseport_id = reuse->reuseport_id;
8847 reuse_kern->bind_inany = reuse->bind_inany;
8848 }
8849
bpf_run_sk_reuseport(struct sock_reuseport * reuse,struct sock * sk,struct bpf_prog * prog,struct sk_buff * skb,u32 hash)8850 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
8851 struct bpf_prog *prog, struct sk_buff *skb,
8852 u32 hash)
8853 {
8854 struct sk_reuseport_kern reuse_kern;
8855 enum sk_action action;
8856
8857 bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, hash);
8858 action = BPF_PROG_RUN(prog, &reuse_kern);
8859
8860 if (action == SK_PASS)
8861 return reuse_kern.selected_sk;
8862 else
8863 return ERR_PTR(-ECONNREFUSED);
8864 }
8865
BPF_CALL_4(sk_select_reuseport,struct sk_reuseport_kern *,reuse_kern,struct bpf_map *,map,void *,key,u32,flags)8866 BPF_CALL_4(sk_select_reuseport, struct sk_reuseport_kern *, reuse_kern,
8867 struct bpf_map *, map, void *, key, u32, flags)
8868 {
8869 struct sock_reuseport *reuse;
8870 struct sock *selected_sk;
8871
8872 selected_sk = map->ops->map_lookup_elem(map, key);
8873 if (!selected_sk)
8874 return -ENOENT;
8875
8876 reuse = rcu_dereference(selected_sk->sk_reuseport_cb);
8877 if (!reuse)
8878 /* selected_sk is unhashed (e.g. by close()) after the
8879 * above map_lookup_elem(). Treat selected_sk has already
8880 * been removed from the map.
8881 */
8882 return -ENOENT;
8883
8884 if (unlikely(reuse->reuseport_id != reuse_kern->reuseport_id)) {
8885 struct sock *sk;
8886
8887 if (unlikely(!reuse_kern->reuseport_id))
8888 /* There is a small race between adding the
8889 * sk to the map and setting the
8890 * reuse_kern->reuseport_id.
8891 * Treat it as the sk has not been added to
8892 * the bpf map yet.
8893 */
8894 return -ENOENT;
8895
8896 sk = reuse_kern->sk;
8897 if (sk->sk_protocol != selected_sk->sk_protocol)
8898 return -EPROTOTYPE;
8899 else if (sk->sk_family != selected_sk->sk_family)
8900 return -EAFNOSUPPORT;
8901
8902 /* Catch all. Likely bound to a different sockaddr. */
8903 return -EBADFD;
8904 }
8905
8906 reuse_kern->selected_sk = selected_sk;
8907
8908 return 0;
8909 }
8910
8911 static const struct bpf_func_proto sk_select_reuseport_proto = {
8912 .func = sk_select_reuseport,
8913 .gpl_only = false,
8914 .ret_type = RET_INTEGER,
8915 .arg1_type = ARG_PTR_TO_CTX,
8916 .arg2_type = ARG_CONST_MAP_PTR,
8917 .arg3_type = ARG_PTR_TO_MAP_KEY,
8918 .arg4_type = ARG_ANYTHING,
8919 };
8920
BPF_CALL_4(sk_reuseport_load_bytes,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len)8921 BPF_CALL_4(sk_reuseport_load_bytes,
8922 const struct sk_reuseport_kern *, reuse_kern, u32, offset,
8923 void *, to, u32, len)
8924 {
8925 return ____bpf_skb_load_bytes(reuse_kern->skb, offset, to, len);
8926 }
8927
8928 static const struct bpf_func_proto sk_reuseport_load_bytes_proto = {
8929 .func = sk_reuseport_load_bytes,
8930 .gpl_only = false,
8931 .ret_type = RET_INTEGER,
8932 .arg1_type = ARG_PTR_TO_CTX,
8933 .arg2_type = ARG_ANYTHING,
8934 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
8935 .arg4_type = ARG_CONST_SIZE,
8936 };
8937
BPF_CALL_5(sk_reuseport_load_bytes_relative,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len,u32,start_header)8938 BPF_CALL_5(sk_reuseport_load_bytes_relative,
8939 const struct sk_reuseport_kern *, reuse_kern, u32, offset,
8940 void *, to, u32, len, u32, start_header)
8941 {
8942 return ____bpf_skb_load_bytes_relative(reuse_kern->skb, offset, to,
8943 len, start_header);
8944 }
8945
8946 static const struct bpf_func_proto sk_reuseport_load_bytes_relative_proto = {
8947 .func = sk_reuseport_load_bytes_relative,
8948 .gpl_only = false,
8949 .ret_type = RET_INTEGER,
8950 .arg1_type = ARG_PTR_TO_CTX,
8951 .arg2_type = ARG_ANYTHING,
8952 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
8953 .arg4_type = ARG_CONST_SIZE,
8954 .arg5_type = ARG_ANYTHING,
8955 };
8956
8957 static const struct bpf_func_proto *
sk_reuseport_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8958 sk_reuseport_func_proto(enum bpf_func_id func_id,
8959 const struct bpf_prog *prog)
8960 {
8961 switch (func_id) {
8962 case BPF_FUNC_sk_select_reuseport:
8963 return &sk_select_reuseport_proto;
8964 case BPF_FUNC_skb_load_bytes:
8965 return &sk_reuseport_load_bytes_proto;
8966 case BPF_FUNC_skb_load_bytes_relative:
8967 return &sk_reuseport_load_bytes_relative_proto;
8968 default:
8969 return bpf_base_func_proto(func_id);
8970 }
8971 }
8972
8973 static bool
sk_reuseport_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8974 sk_reuseport_is_valid_access(int off, int size,
8975 enum bpf_access_type type,
8976 const struct bpf_prog *prog,
8977 struct bpf_insn_access_aux *info)
8978 {
8979 const u32 size_default = sizeof(__u32);
8980
8981 if (off < 0 || off >= sizeof(struct sk_reuseport_md) ||
8982 off % size || type != BPF_READ)
8983 return false;
8984
8985 switch (off) {
8986 case offsetof(struct sk_reuseport_md, data):
8987 info->reg_type = PTR_TO_PACKET;
8988 return size == sizeof(__u64);
8989
8990 case offsetof(struct sk_reuseport_md, data_end):
8991 info->reg_type = PTR_TO_PACKET_END;
8992 return size == sizeof(__u64);
8993
8994 case offsetof(struct sk_reuseport_md, hash):
8995 return size == size_default;
8996
8997 /* Fields that allow narrowing */
8998 case bpf_ctx_range(struct sk_reuseport_md, eth_protocol):
8999 if (size < FIELD_SIZEOF(struct sk_buff, protocol))
9000 return false;
9001 /* fall through */
9002 case bpf_ctx_range(struct sk_reuseport_md, ip_protocol):
9003 case bpf_ctx_range(struct sk_reuseport_md, bind_inany):
9004 case bpf_ctx_range(struct sk_reuseport_md, len):
9005 bpf_ctx_record_field_size(info, size_default);
9006 return bpf_ctx_narrow_access_ok(off, size, size_default);
9007
9008 default:
9009 return false;
9010 }
9011 }
9012
9013 #define SK_REUSEPORT_LOAD_FIELD(F) ({ \
9014 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_reuseport_kern, F), \
9015 si->dst_reg, si->src_reg, \
9016 bpf_target_off(struct sk_reuseport_kern, F, \
9017 FIELD_SIZEOF(struct sk_reuseport_kern, F), \
9018 target_size)); \
9019 })
9020
9021 #define SK_REUSEPORT_LOAD_SKB_FIELD(SKB_FIELD) \
9022 SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern, \
9023 struct sk_buff, \
9024 skb, \
9025 SKB_FIELD)
9026
9027 #define SK_REUSEPORT_LOAD_SK_FIELD_SIZE_OFF(SK_FIELD, BPF_SIZE, EXTRA_OFF) \
9028 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(struct sk_reuseport_kern, \
9029 struct sock, \
9030 sk, \
9031 SK_FIELD, BPF_SIZE, EXTRA_OFF)
9032
sk_reuseport_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9033 static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type,
9034 const struct bpf_insn *si,
9035 struct bpf_insn *insn_buf,
9036 struct bpf_prog *prog,
9037 u32 *target_size)
9038 {
9039 struct bpf_insn *insn = insn_buf;
9040
9041 switch (si->off) {
9042 case offsetof(struct sk_reuseport_md, data):
9043 SK_REUSEPORT_LOAD_SKB_FIELD(data);
9044 break;
9045
9046 case offsetof(struct sk_reuseport_md, len):
9047 SK_REUSEPORT_LOAD_SKB_FIELD(len);
9048 break;
9049
9050 case offsetof(struct sk_reuseport_md, eth_protocol):
9051 SK_REUSEPORT_LOAD_SKB_FIELD(protocol);
9052 break;
9053
9054 case offsetof(struct sk_reuseport_md, ip_protocol):
9055 BUILD_BUG_ON(HWEIGHT32(SK_FL_PROTO_MASK) != BITS_PER_BYTE);
9056 SK_REUSEPORT_LOAD_SK_FIELD_SIZE_OFF(__sk_flags_offset,
9057 BPF_W, 0);
9058 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
9059 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg,
9060 SK_FL_PROTO_SHIFT);
9061 /* SK_FL_PROTO_MASK and SK_FL_PROTO_SHIFT are endian
9062 * aware. No further narrowing or masking is needed.
9063 */
9064 *target_size = 1;
9065 break;
9066
9067 case offsetof(struct sk_reuseport_md, data_end):
9068 SK_REUSEPORT_LOAD_FIELD(data_end);
9069 break;
9070
9071 case offsetof(struct sk_reuseport_md, hash):
9072 SK_REUSEPORT_LOAD_FIELD(hash);
9073 break;
9074
9075 case offsetof(struct sk_reuseport_md, bind_inany):
9076 SK_REUSEPORT_LOAD_FIELD(bind_inany);
9077 break;
9078 }
9079
9080 return insn - insn_buf;
9081 }
9082
9083 const struct bpf_verifier_ops sk_reuseport_verifier_ops = {
9084 .get_func_proto = sk_reuseport_func_proto,
9085 .is_valid_access = sk_reuseport_is_valid_access,
9086 .convert_ctx_access = sk_reuseport_convert_ctx_access,
9087 };
9088
9089 const struct bpf_prog_ops sk_reuseport_prog_ops = {
9090 };
9091 #endif /* CONFIG_INET */
9092