1 /*
2 * Copyright (c) 2007-2017 Nicira, Inc.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of version 2 of the GNU General Public
6 * License as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
16 * 02110-1301, USA
17 */
18
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20
21 #include <linux/skbuff.h>
22 #include <linux/in.h>
23 #include <linux/ip.h>
24 #include <linux/openvswitch.h>
25 #include <linux/netfilter_ipv6.h>
26 #include <linux/sctp.h>
27 #include <linux/tcp.h>
28 #include <linux/udp.h>
29 #include <linux/in6.h>
30 #include <linux/if_arp.h>
31 #include <linux/if_vlan.h>
32
33 #include <net/dst.h>
34 #include <net/ip.h>
35 #include <net/ipv6.h>
36 #include <net/ip6_fib.h>
37 #include <net/checksum.h>
38 #include <net/dsfield.h>
39 #include <net/mpls.h>
40 #include <net/sctp/checksum.h>
41
42 #include "datapath.h"
43 #include "flow.h"
44 #include "conntrack.h"
45 #include "vport.h"
46
47 struct deferred_action {
48 struct sk_buff *skb;
49 const struct nlattr *actions;
50 int actions_len;
51
52 /* Store pkt_key clone when creating deferred action. */
53 struct sw_flow_key pkt_key;
54 };
55
56 #define MAX_L2_LEN (VLAN_ETH_HLEN + 3 * MPLS_HLEN)
57 struct ovs_frag_data {
58 unsigned long dst;
59 struct vport *vport;
60 struct ovs_skb_cb cb;
61 __be16 inner_protocol;
62 u16 network_offset; /* valid only for MPLS */
63 u16 vlan_tci;
64 __be16 vlan_proto;
65 unsigned int l2_len;
66 u8 mac_proto;
67 u8 l2_data[MAX_L2_LEN];
68 };
69
70 static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage);
71
72 #define DEFERRED_ACTION_FIFO_SIZE 10
73 #define OVS_RECURSION_LIMIT 5
74 #define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2)
75 struct action_fifo {
76 int head;
77 int tail;
78 /* Deferred action fifo queue storage. */
79 struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
80 };
81
82 struct action_flow_keys {
83 struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD];
84 };
85
86 static struct action_fifo __percpu *action_fifos;
87 static struct action_flow_keys __percpu *flow_keys;
88 static DEFINE_PER_CPU(int, exec_actions_level);
89
90 /* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys'
91 * space. Return NULL if out of key spaces.
92 */
clone_key(const struct sw_flow_key * key_)93 static struct sw_flow_key *clone_key(const struct sw_flow_key *key_)
94 {
95 struct action_flow_keys *keys = this_cpu_ptr(flow_keys);
96 int level = this_cpu_read(exec_actions_level);
97 struct sw_flow_key *key = NULL;
98
99 if (level <= OVS_DEFERRED_ACTION_THRESHOLD) {
100 key = &keys->key[level - 1];
101 *key = *key_;
102 }
103
104 return key;
105 }
106
action_fifo_init(struct action_fifo * fifo)107 static void action_fifo_init(struct action_fifo *fifo)
108 {
109 fifo->head = 0;
110 fifo->tail = 0;
111 }
112
action_fifo_is_empty(const struct action_fifo * fifo)113 static bool action_fifo_is_empty(const struct action_fifo *fifo)
114 {
115 return (fifo->head == fifo->tail);
116 }
117
action_fifo_get(struct action_fifo * fifo)118 static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
119 {
120 if (action_fifo_is_empty(fifo))
121 return NULL;
122
123 return &fifo->fifo[fifo->tail++];
124 }
125
action_fifo_put(struct action_fifo * fifo)126 static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
127 {
128 if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
129 return NULL;
130
131 return &fifo->fifo[fifo->head++];
132 }
133
134 /* Return true if fifo is not full */
add_deferred_actions(struct sk_buff * skb,const struct sw_flow_key * key,const struct nlattr * actions,const int actions_len)135 static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
136 const struct sw_flow_key *key,
137 const struct nlattr *actions,
138 const int actions_len)
139 {
140 struct action_fifo *fifo;
141 struct deferred_action *da;
142
143 fifo = this_cpu_ptr(action_fifos);
144 da = action_fifo_put(fifo);
145 if (da) {
146 da->skb = skb;
147 da->actions = actions;
148 da->actions_len = actions_len;
149 da->pkt_key = *key;
150 }
151
152 return da;
153 }
154
invalidate_flow_key(struct sw_flow_key * key)155 static void invalidate_flow_key(struct sw_flow_key *key)
156 {
157 key->mac_proto |= SW_FLOW_KEY_INVALID;
158 }
159
is_flow_key_valid(const struct sw_flow_key * key)160 static bool is_flow_key_valid(const struct sw_flow_key *key)
161 {
162 return !(key->mac_proto & SW_FLOW_KEY_INVALID);
163 }
164
165 static int clone_execute(struct datapath *dp, struct sk_buff *skb,
166 struct sw_flow_key *key,
167 u32 recirc_id,
168 const struct nlattr *actions, int len,
169 bool last, bool clone_flow_key);
170
update_ethertype(struct sk_buff * skb,struct ethhdr * hdr,__be16 ethertype)171 static void update_ethertype(struct sk_buff *skb, struct ethhdr *hdr,
172 __be16 ethertype)
173 {
174 if (skb->ip_summed == CHECKSUM_COMPLETE) {
175 __be16 diff[] = { ~(hdr->h_proto), ethertype };
176
177 skb->csum = csum_partial((char *)diff, sizeof(diff), skb->csum);
178 }
179
180 hdr->h_proto = ethertype;
181 }
182
push_mpls(struct sk_buff * skb,struct sw_flow_key * key,const struct ovs_action_push_mpls * mpls)183 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
184 const struct ovs_action_push_mpls *mpls)
185 {
186 struct mpls_shim_hdr *new_mpls_lse;
187
188 /* Networking stack do not allow simultaneous Tunnel and MPLS GSO. */
189 if (skb->encapsulation)
190 return -ENOTSUPP;
191
192 if (skb_cow_head(skb, MPLS_HLEN) < 0)
193 return -ENOMEM;
194
195 if (!skb->inner_protocol) {
196 skb_set_inner_network_header(skb, skb->mac_len);
197 skb_set_inner_protocol(skb, skb->protocol);
198 }
199
200 skb_push(skb, MPLS_HLEN);
201 memmove(skb_mac_header(skb) - MPLS_HLEN, skb_mac_header(skb),
202 skb->mac_len);
203 skb_reset_mac_header(skb);
204 skb_set_network_header(skb, skb->mac_len);
205
206 new_mpls_lse = mpls_hdr(skb);
207 new_mpls_lse->label_stack_entry = mpls->mpls_lse;
208
209 skb_postpush_rcsum(skb, new_mpls_lse, MPLS_HLEN);
210
211 if (ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET)
212 update_ethertype(skb, eth_hdr(skb), mpls->mpls_ethertype);
213 skb->protocol = mpls->mpls_ethertype;
214
215 invalidate_flow_key(key);
216 return 0;
217 }
218
pop_mpls(struct sk_buff * skb,struct sw_flow_key * key,const __be16 ethertype)219 static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
220 const __be16 ethertype)
221 {
222 int err;
223
224 err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
225 if (unlikely(err))
226 return err;
227
228 skb_postpull_rcsum(skb, mpls_hdr(skb), MPLS_HLEN);
229
230 memmove(skb_mac_header(skb) + MPLS_HLEN, skb_mac_header(skb),
231 skb->mac_len);
232
233 __skb_pull(skb, MPLS_HLEN);
234 skb_reset_mac_header(skb);
235 skb_set_network_header(skb, skb->mac_len);
236
237 if (ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET) {
238 struct ethhdr *hdr;
239
240 /* mpls_hdr() is used to locate the ethertype field correctly in the
241 * presence of VLAN tags.
242 */
243 hdr = (struct ethhdr *)((void *)mpls_hdr(skb) - ETH_HLEN);
244 update_ethertype(skb, hdr, ethertype);
245 }
246 if (eth_p_mpls(skb->protocol))
247 skb->protocol = ethertype;
248
249 invalidate_flow_key(key);
250 return 0;
251 }
252
set_mpls(struct sk_buff * skb,struct sw_flow_key * flow_key,const __be32 * mpls_lse,const __be32 * mask)253 static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
254 const __be32 *mpls_lse, const __be32 *mask)
255 {
256 struct mpls_shim_hdr *stack;
257 __be32 lse;
258 int err;
259
260 err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
261 if (unlikely(err))
262 return err;
263
264 stack = mpls_hdr(skb);
265 lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask);
266 if (skb->ip_summed == CHECKSUM_COMPLETE) {
267 __be32 diff[] = { ~(stack->label_stack_entry), lse };
268
269 skb->csum = csum_partial((char *)diff, sizeof(diff), skb->csum);
270 }
271
272 stack->label_stack_entry = lse;
273 flow_key->mpls.top_lse = lse;
274 return 0;
275 }
276
pop_vlan(struct sk_buff * skb,struct sw_flow_key * key)277 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
278 {
279 int err;
280
281 err = skb_vlan_pop(skb);
282 if (skb_vlan_tag_present(skb)) {
283 invalidate_flow_key(key);
284 } else {
285 key->eth.vlan.tci = 0;
286 key->eth.vlan.tpid = 0;
287 }
288 return err;
289 }
290
push_vlan(struct sk_buff * skb,struct sw_flow_key * key,const struct ovs_action_push_vlan * vlan)291 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
292 const struct ovs_action_push_vlan *vlan)
293 {
294 if (skb_vlan_tag_present(skb)) {
295 invalidate_flow_key(key);
296 } else {
297 key->eth.vlan.tci = vlan->vlan_tci;
298 key->eth.vlan.tpid = vlan->vlan_tpid;
299 }
300 return skb_vlan_push(skb, vlan->vlan_tpid,
301 ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
302 }
303
304 /* 'src' is already properly masked. */
ether_addr_copy_masked(u8 * dst_,const u8 * src_,const u8 * mask_)305 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
306 {
307 u16 *dst = (u16 *)dst_;
308 const u16 *src = (const u16 *)src_;
309 const u16 *mask = (const u16 *)mask_;
310
311 OVS_SET_MASKED(dst[0], src[0], mask[0]);
312 OVS_SET_MASKED(dst[1], src[1], mask[1]);
313 OVS_SET_MASKED(dst[2], src[2], mask[2]);
314 }
315
set_eth_addr(struct sk_buff * skb,struct sw_flow_key * flow_key,const struct ovs_key_ethernet * key,const struct ovs_key_ethernet * mask)316 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
317 const struct ovs_key_ethernet *key,
318 const struct ovs_key_ethernet *mask)
319 {
320 int err;
321
322 err = skb_ensure_writable(skb, ETH_HLEN);
323 if (unlikely(err))
324 return err;
325
326 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
327
328 ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
329 mask->eth_src);
330 ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
331 mask->eth_dst);
332
333 skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
334
335 ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
336 ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
337 return 0;
338 }
339
340 /* pop_eth does not support VLAN packets as this action is never called
341 * for them.
342 */
pop_eth(struct sk_buff * skb,struct sw_flow_key * key)343 static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key)
344 {
345 skb_pull_rcsum(skb, ETH_HLEN);
346 skb_reset_mac_header(skb);
347 skb_reset_mac_len(skb);
348
349 /* safe right before invalidate_flow_key */
350 key->mac_proto = MAC_PROTO_NONE;
351 invalidate_flow_key(key);
352 return 0;
353 }
354
push_eth(struct sk_buff * skb,struct sw_flow_key * key,const struct ovs_action_push_eth * ethh)355 static int push_eth(struct sk_buff *skb, struct sw_flow_key *key,
356 const struct ovs_action_push_eth *ethh)
357 {
358 struct ethhdr *hdr;
359
360 /* Add the new Ethernet header */
361 if (skb_cow_head(skb, ETH_HLEN) < 0)
362 return -ENOMEM;
363
364 skb_push(skb, ETH_HLEN);
365 skb_reset_mac_header(skb);
366 skb_reset_mac_len(skb);
367
368 hdr = eth_hdr(skb);
369 ether_addr_copy(hdr->h_source, ethh->addresses.eth_src);
370 ether_addr_copy(hdr->h_dest, ethh->addresses.eth_dst);
371 hdr->h_proto = skb->protocol;
372
373 skb_postpush_rcsum(skb, hdr, ETH_HLEN);
374
375 /* safe right before invalidate_flow_key */
376 key->mac_proto = MAC_PROTO_ETHERNET;
377 invalidate_flow_key(key);
378 return 0;
379 }
380
update_ip_l4_checksum(struct sk_buff * skb,struct iphdr * nh,__be32 addr,__be32 new_addr)381 static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
382 __be32 addr, __be32 new_addr)
383 {
384 int transport_len = skb->len - skb_transport_offset(skb);
385
386 if (nh->frag_off & htons(IP_OFFSET))
387 return;
388
389 if (nh->protocol == IPPROTO_TCP) {
390 if (likely(transport_len >= sizeof(struct tcphdr)))
391 inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
392 addr, new_addr, true);
393 } else if (nh->protocol == IPPROTO_UDP) {
394 if (likely(transport_len >= sizeof(struct udphdr))) {
395 struct udphdr *uh = udp_hdr(skb);
396
397 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
398 inet_proto_csum_replace4(&uh->check, skb,
399 addr, new_addr, true);
400 if (!uh->check)
401 uh->check = CSUM_MANGLED_0;
402 }
403 }
404 }
405 }
406
set_ip_addr(struct sk_buff * skb,struct iphdr * nh,__be32 * addr,__be32 new_addr)407 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
408 __be32 *addr, __be32 new_addr)
409 {
410 update_ip_l4_checksum(skb, nh, *addr, new_addr);
411 csum_replace4(&nh->check, *addr, new_addr);
412 skb_clear_hash(skb);
413 *addr = new_addr;
414 }
415
update_ipv6_checksum(struct sk_buff * skb,u8 l4_proto,__be32 addr[4],const __be32 new_addr[4])416 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
417 __be32 addr[4], const __be32 new_addr[4])
418 {
419 int transport_len = skb->len - skb_transport_offset(skb);
420
421 if (l4_proto == NEXTHDR_TCP) {
422 if (likely(transport_len >= sizeof(struct tcphdr)))
423 inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
424 addr, new_addr, true);
425 } else if (l4_proto == NEXTHDR_UDP) {
426 if (likely(transport_len >= sizeof(struct udphdr))) {
427 struct udphdr *uh = udp_hdr(skb);
428
429 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
430 inet_proto_csum_replace16(&uh->check, skb,
431 addr, new_addr, true);
432 if (!uh->check)
433 uh->check = CSUM_MANGLED_0;
434 }
435 }
436 } else if (l4_proto == NEXTHDR_ICMP) {
437 if (likely(transport_len >= sizeof(struct icmp6hdr)))
438 inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
439 skb, addr, new_addr, true);
440 }
441 }
442
mask_ipv6_addr(const __be32 old[4],const __be32 addr[4],const __be32 mask[4],__be32 masked[4])443 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
444 const __be32 mask[4], __be32 masked[4])
445 {
446 masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
447 masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
448 masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
449 masked[3] = OVS_MASKED(old[3], addr[3], mask[3]);
450 }
451
set_ipv6_addr(struct sk_buff * skb,u8 l4_proto,__be32 addr[4],const __be32 new_addr[4],bool recalculate_csum)452 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
453 __be32 addr[4], const __be32 new_addr[4],
454 bool recalculate_csum)
455 {
456 if (recalculate_csum)
457 update_ipv6_checksum(skb, l4_proto, addr, new_addr);
458
459 skb_clear_hash(skb);
460 memcpy(addr, new_addr, sizeof(__be32[4]));
461 }
462
set_ipv6_fl(struct ipv6hdr * nh,u32 fl,u32 mask)463 static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask)
464 {
465 /* Bits 21-24 are always unmasked, so this retains their values. */
466 OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16));
467 OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8));
468 OVS_SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask);
469 }
470
set_ip_ttl(struct sk_buff * skb,struct iphdr * nh,u8 new_ttl,u8 mask)471 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
472 u8 mask)
473 {
474 new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask);
475
476 csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
477 nh->ttl = new_ttl;
478 }
479
set_ipv4(struct sk_buff * skb,struct sw_flow_key * flow_key,const struct ovs_key_ipv4 * key,const struct ovs_key_ipv4 * mask)480 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
481 const struct ovs_key_ipv4 *key,
482 const struct ovs_key_ipv4 *mask)
483 {
484 struct iphdr *nh;
485 __be32 new_addr;
486 int err;
487
488 err = skb_ensure_writable(skb, skb_network_offset(skb) +
489 sizeof(struct iphdr));
490 if (unlikely(err))
491 return err;
492
493 nh = ip_hdr(skb);
494
495 /* Setting an IP addresses is typically only a side effect of
496 * matching on them in the current userspace implementation, so it
497 * makes sense to check if the value actually changed.
498 */
499 if (mask->ipv4_src) {
500 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
501
502 if (unlikely(new_addr != nh->saddr)) {
503 set_ip_addr(skb, nh, &nh->saddr, new_addr);
504 flow_key->ipv4.addr.src = new_addr;
505 }
506 }
507 if (mask->ipv4_dst) {
508 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
509
510 if (unlikely(new_addr != nh->daddr)) {
511 set_ip_addr(skb, nh, &nh->daddr, new_addr);
512 flow_key->ipv4.addr.dst = new_addr;
513 }
514 }
515 if (mask->ipv4_tos) {
516 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
517 flow_key->ip.tos = nh->tos;
518 }
519 if (mask->ipv4_ttl) {
520 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
521 flow_key->ip.ttl = nh->ttl;
522 }
523
524 return 0;
525 }
526
is_ipv6_mask_nonzero(const __be32 addr[4])527 static bool is_ipv6_mask_nonzero(const __be32 addr[4])
528 {
529 return !!(addr[0] | addr[1] | addr[2] | addr[3]);
530 }
531
set_ipv6(struct sk_buff * skb,struct sw_flow_key * flow_key,const struct ovs_key_ipv6 * key,const struct ovs_key_ipv6 * mask)532 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
533 const struct ovs_key_ipv6 *key,
534 const struct ovs_key_ipv6 *mask)
535 {
536 struct ipv6hdr *nh;
537 int err;
538
539 err = skb_ensure_writable(skb, skb_network_offset(skb) +
540 sizeof(struct ipv6hdr));
541 if (unlikely(err))
542 return err;
543
544 nh = ipv6_hdr(skb);
545
546 /* Setting an IP addresses is typically only a side effect of
547 * matching on them in the current userspace implementation, so it
548 * makes sense to check if the value actually changed.
549 */
550 if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
551 __be32 *saddr = (__be32 *)&nh->saddr;
552 __be32 masked[4];
553
554 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);
555
556 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
557 set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked,
558 true);
559 memcpy(&flow_key->ipv6.addr.src, masked,
560 sizeof(flow_key->ipv6.addr.src));
561 }
562 }
563 if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
564 unsigned int offset = 0;
565 int flags = IP6_FH_F_SKIP_RH;
566 bool recalc_csum = true;
567 __be32 *daddr = (__be32 *)&nh->daddr;
568 __be32 masked[4];
569
570 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);
571
572 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
573 if (ipv6_ext_hdr(nh->nexthdr))
574 recalc_csum = (ipv6_find_hdr(skb, &offset,
575 NEXTHDR_ROUTING,
576 NULL, &flags)
577 != NEXTHDR_ROUTING);
578
579 set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked,
580 recalc_csum);
581 memcpy(&flow_key->ipv6.addr.dst, masked,
582 sizeof(flow_key->ipv6.addr.dst));
583 }
584 }
585 if (mask->ipv6_tclass) {
586 ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass);
587 flow_key->ip.tos = ipv6_get_dsfield(nh);
588 }
589 if (mask->ipv6_label) {
590 set_ipv6_fl(nh, ntohl(key->ipv6_label),
591 ntohl(mask->ipv6_label));
592 flow_key->ipv6.label =
593 *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
594 }
595 if (mask->ipv6_hlimit) {
596 OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit,
597 mask->ipv6_hlimit);
598 flow_key->ip.ttl = nh->hop_limit;
599 }
600 return 0;
601 }
602
603 /* Must follow skb_ensure_writable() since that can move the skb data. */
set_tp_port(struct sk_buff * skb,__be16 * port,__be16 new_port,__sum16 * check)604 static void set_tp_port(struct sk_buff *skb, __be16 *port,
605 __be16 new_port, __sum16 *check)
606 {
607 inet_proto_csum_replace2(check, skb, *port, new_port, false);
608 *port = new_port;
609 }
610
set_udp(struct sk_buff * skb,struct sw_flow_key * flow_key,const struct ovs_key_udp * key,const struct ovs_key_udp * mask)611 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
612 const struct ovs_key_udp *key,
613 const struct ovs_key_udp *mask)
614 {
615 struct udphdr *uh;
616 __be16 src, dst;
617 int err;
618
619 err = skb_ensure_writable(skb, skb_transport_offset(skb) +
620 sizeof(struct udphdr));
621 if (unlikely(err))
622 return err;
623
624 uh = udp_hdr(skb);
625 /* Either of the masks is non-zero, so do not bother checking them. */
626 src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
627 dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst);
628
629 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
630 if (likely(src != uh->source)) {
631 set_tp_port(skb, &uh->source, src, &uh->check);
632 flow_key->tp.src = src;
633 }
634 if (likely(dst != uh->dest)) {
635 set_tp_port(skb, &uh->dest, dst, &uh->check);
636 flow_key->tp.dst = dst;
637 }
638
639 if (unlikely(!uh->check))
640 uh->check = CSUM_MANGLED_0;
641 } else {
642 uh->source = src;
643 uh->dest = dst;
644 flow_key->tp.src = src;
645 flow_key->tp.dst = dst;
646 }
647
648 skb_clear_hash(skb);
649
650 return 0;
651 }
652
set_tcp(struct sk_buff * skb,struct sw_flow_key * flow_key,const struct ovs_key_tcp * key,const struct ovs_key_tcp * mask)653 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
654 const struct ovs_key_tcp *key,
655 const struct ovs_key_tcp *mask)
656 {
657 struct tcphdr *th;
658 __be16 src, dst;
659 int err;
660
661 err = skb_ensure_writable(skb, skb_transport_offset(skb) +
662 sizeof(struct tcphdr));
663 if (unlikely(err))
664 return err;
665
666 th = tcp_hdr(skb);
667 src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src);
668 if (likely(src != th->source)) {
669 set_tp_port(skb, &th->source, src, &th->check);
670 flow_key->tp.src = src;
671 }
672 dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
673 if (likely(dst != th->dest)) {
674 set_tp_port(skb, &th->dest, dst, &th->check);
675 flow_key->tp.dst = dst;
676 }
677 skb_clear_hash(skb);
678
679 return 0;
680 }
681
set_sctp(struct sk_buff * skb,struct sw_flow_key * flow_key,const struct ovs_key_sctp * key,const struct ovs_key_sctp * mask)682 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
683 const struct ovs_key_sctp *key,
684 const struct ovs_key_sctp *mask)
685 {
686 unsigned int sctphoff = skb_transport_offset(skb);
687 struct sctphdr *sh;
688 __le32 old_correct_csum, new_csum, old_csum;
689 int err;
690
691 err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
692 if (unlikely(err))
693 return err;
694
695 sh = sctp_hdr(skb);
696 old_csum = sh->checksum;
697 old_correct_csum = sctp_compute_cksum(skb, sctphoff);
698
699 sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
700 sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
701
702 new_csum = sctp_compute_cksum(skb, sctphoff);
703
704 /* Carry any checksum errors through. */
705 sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
706
707 skb_clear_hash(skb);
708 flow_key->tp.src = sh->source;
709 flow_key->tp.dst = sh->dest;
710
711 return 0;
712 }
713
ovs_vport_output(struct net * net,struct sock * sk,struct sk_buff * skb)714 static int ovs_vport_output(struct net *net, struct sock *sk, struct sk_buff *skb)
715 {
716 struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
717 struct vport *vport = data->vport;
718
719 if (skb_cow_head(skb, data->l2_len) < 0) {
720 kfree_skb(skb);
721 return -ENOMEM;
722 }
723
724 __skb_dst_copy(skb, data->dst);
725 *OVS_CB(skb) = data->cb;
726 skb->inner_protocol = data->inner_protocol;
727 skb->vlan_tci = data->vlan_tci;
728 skb->vlan_proto = data->vlan_proto;
729
730 /* Reconstruct the MAC header. */
731 skb_push(skb, data->l2_len);
732 memcpy(skb->data, &data->l2_data, data->l2_len);
733 skb_postpush_rcsum(skb, skb->data, data->l2_len);
734 skb_reset_mac_header(skb);
735
736 if (eth_p_mpls(skb->protocol)) {
737 skb->inner_network_header = skb->network_header;
738 skb_set_network_header(skb, data->network_offset);
739 skb_reset_mac_len(skb);
740 }
741
742 ovs_vport_send(vport, skb, data->mac_proto);
743 return 0;
744 }
745
746 static unsigned int
ovs_dst_get_mtu(const struct dst_entry * dst)747 ovs_dst_get_mtu(const struct dst_entry *dst)
748 {
749 return dst->dev->mtu;
750 }
751
752 static struct dst_ops ovs_dst_ops = {
753 .family = AF_UNSPEC,
754 .mtu = ovs_dst_get_mtu,
755 };
756
757 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
758 * ovs_vport_output(), which is called once per fragmented packet.
759 */
prepare_frag(struct vport * vport,struct sk_buff * skb,u16 orig_network_offset,u8 mac_proto)760 static void prepare_frag(struct vport *vport, struct sk_buff *skb,
761 u16 orig_network_offset, u8 mac_proto)
762 {
763 unsigned int hlen = skb_network_offset(skb);
764 struct ovs_frag_data *data;
765
766 data = this_cpu_ptr(&ovs_frag_data_storage);
767 data->dst = skb->_skb_refdst;
768 data->vport = vport;
769 data->cb = *OVS_CB(skb);
770 data->inner_protocol = skb->inner_protocol;
771 data->network_offset = orig_network_offset;
772 data->vlan_tci = skb->vlan_tci;
773 data->vlan_proto = skb->vlan_proto;
774 data->mac_proto = mac_proto;
775 data->l2_len = hlen;
776 memcpy(&data->l2_data, skb->data, hlen);
777
778 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
779 skb_pull(skb, hlen);
780 }
781
ovs_fragment(struct net * net,struct vport * vport,struct sk_buff * skb,u16 mru,struct sw_flow_key * key)782 static void ovs_fragment(struct net *net, struct vport *vport,
783 struct sk_buff *skb, u16 mru,
784 struct sw_flow_key *key)
785 {
786 u16 orig_network_offset = 0;
787
788 if (eth_p_mpls(skb->protocol)) {
789 orig_network_offset = skb_network_offset(skb);
790 skb->network_header = skb->inner_network_header;
791 }
792
793 if (skb_network_offset(skb) > MAX_L2_LEN) {
794 OVS_NLERR(1, "L2 header too long to fragment");
795 goto err;
796 }
797
798 if (key->eth.type == htons(ETH_P_IP)) {
799 struct dst_entry ovs_dst;
800 unsigned long orig_dst;
801
802 prepare_frag(vport, skb, orig_network_offset,
803 ovs_key_mac_proto(key));
804 dst_init(&ovs_dst, &ovs_dst_ops, NULL, 1,
805 DST_OBSOLETE_NONE, DST_NOCOUNT);
806 ovs_dst.dev = vport->dev;
807
808 orig_dst = skb->_skb_refdst;
809 skb_dst_set_noref(skb, &ovs_dst);
810 IPCB(skb)->frag_max_size = mru;
811
812 ip_do_fragment(net, skb->sk, skb, ovs_vport_output);
813 refdst_drop(orig_dst);
814 } else if (key->eth.type == htons(ETH_P_IPV6)) {
815 const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
816 unsigned long orig_dst;
817 struct rt6_info ovs_rt;
818
819 if (!v6ops)
820 goto err;
821
822 prepare_frag(vport, skb, orig_network_offset,
823 ovs_key_mac_proto(key));
824 memset(&ovs_rt, 0, sizeof(ovs_rt));
825 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
826 DST_OBSOLETE_NONE, DST_NOCOUNT);
827 ovs_rt.dst.dev = vport->dev;
828
829 orig_dst = skb->_skb_refdst;
830 skb_dst_set_noref(skb, &ovs_rt.dst);
831 IP6CB(skb)->frag_max_size = mru;
832
833 v6ops->fragment(net, skb->sk, skb, ovs_vport_output);
834 refdst_drop(orig_dst);
835 } else {
836 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
837 ovs_vport_name(vport), ntohs(key->eth.type), mru,
838 vport->dev->mtu);
839 goto err;
840 }
841
842 return;
843 err:
844 kfree_skb(skb);
845 }
846
do_output(struct datapath * dp,struct sk_buff * skb,int out_port,struct sw_flow_key * key)847 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
848 struct sw_flow_key *key)
849 {
850 struct vport *vport = ovs_vport_rcu(dp, out_port);
851
852 if (likely(vport)) {
853 u16 mru = OVS_CB(skb)->mru;
854 u32 cutlen = OVS_CB(skb)->cutlen;
855
856 if (unlikely(cutlen > 0)) {
857 if (skb->len - cutlen > ovs_mac_header_len(key))
858 pskb_trim(skb, skb->len - cutlen);
859 else
860 pskb_trim(skb, ovs_mac_header_len(key));
861 }
862
863 if (likely(!mru ||
864 (skb->len <= mru + vport->dev->hard_header_len))) {
865 ovs_vport_send(vport, skb, ovs_key_mac_proto(key));
866 } else if (mru <= vport->dev->mtu) {
867 struct net *net = read_pnet(&dp->net);
868
869 ovs_fragment(net, vport, skb, mru, key);
870 } else {
871 kfree_skb(skb);
872 }
873 } else {
874 kfree_skb(skb);
875 }
876 }
877
output_userspace(struct datapath * dp,struct sk_buff * skb,struct sw_flow_key * key,const struct nlattr * attr,const struct nlattr * actions,int actions_len,uint32_t cutlen)878 static int output_userspace(struct datapath *dp, struct sk_buff *skb,
879 struct sw_flow_key *key, const struct nlattr *attr,
880 const struct nlattr *actions, int actions_len,
881 uint32_t cutlen)
882 {
883 struct dp_upcall_info upcall;
884 const struct nlattr *a;
885 int rem;
886
887 memset(&upcall, 0, sizeof(upcall));
888 upcall.cmd = OVS_PACKET_CMD_ACTION;
889 upcall.mru = OVS_CB(skb)->mru;
890
891 for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
892 a = nla_next(a, &rem)) {
893 switch (nla_type(a)) {
894 case OVS_USERSPACE_ATTR_USERDATA:
895 upcall.userdata = a;
896 break;
897
898 case OVS_USERSPACE_ATTR_PID:
899 upcall.portid = nla_get_u32(a);
900 break;
901
902 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
903 /* Get out tunnel info. */
904 struct vport *vport;
905
906 vport = ovs_vport_rcu(dp, nla_get_u32(a));
907 if (vport) {
908 int err;
909
910 err = dev_fill_metadata_dst(vport->dev, skb);
911 if (!err)
912 upcall.egress_tun_info = skb_tunnel_info(skb);
913 }
914
915 break;
916 }
917
918 case OVS_USERSPACE_ATTR_ACTIONS: {
919 /* Include actions. */
920 upcall.actions = actions;
921 upcall.actions_len = actions_len;
922 break;
923 }
924
925 } /* End of switch. */
926 }
927
928 return ovs_dp_upcall(dp, skb, key, &upcall, cutlen);
929 }
930
931 /* When 'last' is true, sample() should always consume the 'skb'.
932 * Otherwise, sample() should keep 'skb' intact regardless what
933 * actions are executed within sample().
934 */
sample(struct datapath * dp,struct sk_buff * skb,struct sw_flow_key * key,const struct nlattr * attr,bool last)935 static int sample(struct datapath *dp, struct sk_buff *skb,
936 struct sw_flow_key *key, const struct nlattr *attr,
937 bool last)
938 {
939 struct nlattr *actions;
940 struct nlattr *sample_arg;
941 int rem = nla_len(attr);
942 const struct sample_arg *arg;
943 bool clone_flow_key;
944
945 /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */
946 sample_arg = nla_data(attr);
947 arg = nla_data(sample_arg);
948 actions = nla_next(sample_arg, &rem);
949
950 if ((arg->probability != U32_MAX) &&
951 (!arg->probability || prandom_u32() > arg->probability)) {
952 if (last)
953 consume_skb(skb);
954 return 0;
955 }
956
957 clone_flow_key = !arg->exec;
958 return clone_execute(dp, skb, key, 0, actions, rem, last,
959 clone_flow_key);
960 }
961
execute_hash(struct sk_buff * skb,struct sw_flow_key * key,const struct nlattr * attr)962 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
963 const struct nlattr *attr)
964 {
965 struct ovs_action_hash *hash_act = nla_data(attr);
966 u32 hash = 0;
967
968 /* OVS_HASH_ALG_L4 is the only possible hash algorithm. */
969 hash = skb_get_hash(skb);
970 hash = jhash_1word(hash, hash_act->hash_basis);
971 if (!hash)
972 hash = 0x1;
973
974 key->ovs_flow_hash = hash;
975 }
976
execute_set_action(struct sk_buff * skb,struct sw_flow_key * flow_key,const struct nlattr * a)977 static int execute_set_action(struct sk_buff *skb,
978 struct sw_flow_key *flow_key,
979 const struct nlattr *a)
980 {
981 /* Only tunnel set execution is supported without a mask. */
982 if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
983 struct ovs_tunnel_info *tun = nla_data(a);
984
985 skb_dst_drop(skb);
986 dst_hold((struct dst_entry *)tun->tun_dst);
987 skb_dst_set(skb, (struct dst_entry *)tun->tun_dst);
988 return 0;
989 }
990
991 return -EINVAL;
992 }
993
994 /* Mask is at the midpoint of the data. */
995 #define get_mask(a, type) ((const type)nla_data(a) + 1)
996
execute_masked_set_action(struct sk_buff * skb,struct sw_flow_key * flow_key,const struct nlattr * a)997 static int execute_masked_set_action(struct sk_buff *skb,
998 struct sw_flow_key *flow_key,
999 const struct nlattr *a)
1000 {
1001 int err = 0;
1002
1003 switch (nla_type(a)) {
1004 case OVS_KEY_ATTR_PRIORITY:
1005 OVS_SET_MASKED(skb->priority, nla_get_u32(a),
1006 *get_mask(a, u32 *));
1007 flow_key->phy.priority = skb->priority;
1008 break;
1009
1010 case OVS_KEY_ATTR_SKB_MARK:
1011 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
1012 flow_key->phy.skb_mark = skb->mark;
1013 break;
1014
1015 case OVS_KEY_ATTR_TUNNEL_INFO:
1016 /* Masked data not supported for tunnel. */
1017 err = -EINVAL;
1018 break;
1019
1020 case OVS_KEY_ATTR_ETHERNET:
1021 err = set_eth_addr(skb, flow_key, nla_data(a),
1022 get_mask(a, struct ovs_key_ethernet *));
1023 break;
1024
1025 case OVS_KEY_ATTR_IPV4:
1026 err = set_ipv4(skb, flow_key, nla_data(a),
1027 get_mask(a, struct ovs_key_ipv4 *));
1028 break;
1029
1030 case OVS_KEY_ATTR_IPV6:
1031 err = set_ipv6(skb, flow_key, nla_data(a),
1032 get_mask(a, struct ovs_key_ipv6 *));
1033 break;
1034
1035 case OVS_KEY_ATTR_TCP:
1036 err = set_tcp(skb, flow_key, nla_data(a),
1037 get_mask(a, struct ovs_key_tcp *));
1038 break;
1039
1040 case OVS_KEY_ATTR_UDP:
1041 err = set_udp(skb, flow_key, nla_data(a),
1042 get_mask(a, struct ovs_key_udp *));
1043 break;
1044
1045 case OVS_KEY_ATTR_SCTP:
1046 err = set_sctp(skb, flow_key, nla_data(a),
1047 get_mask(a, struct ovs_key_sctp *));
1048 break;
1049
1050 case OVS_KEY_ATTR_MPLS:
1051 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
1052 __be32 *));
1053 break;
1054
1055 case OVS_KEY_ATTR_CT_STATE:
1056 case OVS_KEY_ATTR_CT_ZONE:
1057 case OVS_KEY_ATTR_CT_MARK:
1058 case OVS_KEY_ATTR_CT_LABELS:
1059 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4:
1060 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6:
1061 err = -EINVAL;
1062 break;
1063 }
1064
1065 return err;
1066 }
1067
execute_recirc(struct datapath * dp,struct sk_buff * skb,struct sw_flow_key * key,const struct nlattr * a,bool last)1068 static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
1069 struct sw_flow_key *key,
1070 const struct nlattr *a, bool last)
1071 {
1072 u32 recirc_id;
1073
1074 if (!is_flow_key_valid(key)) {
1075 int err;
1076
1077 err = ovs_flow_key_update(skb, key);
1078 if (err)
1079 return err;
1080 }
1081 BUG_ON(!is_flow_key_valid(key));
1082
1083 recirc_id = nla_get_u32(a);
1084 return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true);
1085 }
1086
1087 /* Execute a list of actions against 'skb'. */
do_execute_actions(struct datapath * dp,struct sk_buff * skb,struct sw_flow_key * key,const struct nlattr * attr,int len)1088 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
1089 struct sw_flow_key *key,
1090 const struct nlattr *attr, int len)
1091 {
1092 const struct nlattr *a;
1093 int rem;
1094
1095 for (a = attr, rem = len; rem > 0;
1096 a = nla_next(a, &rem)) {
1097 int err = 0;
1098
1099 switch (nla_type(a)) {
1100 case OVS_ACTION_ATTR_OUTPUT: {
1101 int port = nla_get_u32(a);
1102 struct sk_buff *clone;
1103
1104 /* Every output action needs a separate clone
1105 * of 'skb', In case the output action is the
1106 * last action, cloning can be avoided.
1107 */
1108 if (nla_is_last(a, rem)) {
1109 do_output(dp, skb, port, key);
1110 /* 'skb' has been used for output.
1111 */
1112 return 0;
1113 }
1114
1115 clone = skb_clone(skb, GFP_ATOMIC);
1116 if (clone)
1117 do_output(dp, clone, port, key);
1118 OVS_CB(skb)->cutlen = 0;
1119 break;
1120 }
1121
1122 case OVS_ACTION_ATTR_TRUNC: {
1123 struct ovs_action_trunc *trunc = nla_data(a);
1124
1125 if (skb->len > trunc->max_len)
1126 OVS_CB(skb)->cutlen = skb->len - trunc->max_len;
1127 break;
1128 }
1129
1130 case OVS_ACTION_ATTR_USERSPACE:
1131 output_userspace(dp, skb, key, a, attr,
1132 len, OVS_CB(skb)->cutlen);
1133 OVS_CB(skb)->cutlen = 0;
1134 break;
1135
1136 case OVS_ACTION_ATTR_HASH:
1137 execute_hash(skb, key, a);
1138 break;
1139
1140 case OVS_ACTION_ATTR_PUSH_MPLS:
1141 err = push_mpls(skb, key, nla_data(a));
1142 break;
1143
1144 case OVS_ACTION_ATTR_POP_MPLS:
1145 err = pop_mpls(skb, key, nla_get_be16(a));
1146 break;
1147
1148 case OVS_ACTION_ATTR_PUSH_VLAN:
1149 err = push_vlan(skb, key, nla_data(a));
1150 break;
1151
1152 case OVS_ACTION_ATTR_POP_VLAN:
1153 err = pop_vlan(skb, key);
1154 break;
1155
1156 case OVS_ACTION_ATTR_RECIRC: {
1157 bool last = nla_is_last(a, rem);
1158
1159 err = execute_recirc(dp, skb, key, a, last);
1160 if (last) {
1161 /* If this is the last action, the skb has
1162 * been consumed or freed.
1163 * Return immediately.
1164 */
1165 return err;
1166 }
1167 break;
1168 }
1169
1170 case OVS_ACTION_ATTR_SET:
1171 err = execute_set_action(skb, key, nla_data(a));
1172 break;
1173
1174 case OVS_ACTION_ATTR_SET_MASKED:
1175 case OVS_ACTION_ATTR_SET_TO_MASKED:
1176 err = execute_masked_set_action(skb, key, nla_data(a));
1177 break;
1178
1179 case OVS_ACTION_ATTR_SAMPLE: {
1180 bool last = nla_is_last(a, rem);
1181
1182 err = sample(dp, skb, key, a, last);
1183 if (last)
1184 return err;
1185
1186 break;
1187 }
1188
1189 case OVS_ACTION_ATTR_CT:
1190 if (!is_flow_key_valid(key)) {
1191 err = ovs_flow_key_update(skb, key);
1192 if (err)
1193 return err;
1194 }
1195
1196 err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
1197 nla_data(a));
1198
1199 /* Hide stolen IP fragments from user space. */
1200 if (err)
1201 return err == -EINPROGRESS ? 0 : err;
1202 break;
1203
1204 case OVS_ACTION_ATTR_PUSH_ETH:
1205 err = push_eth(skb, key, nla_data(a));
1206 break;
1207
1208 case OVS_ACTION_ATTR_POP_ETH:
1209 err = pop_eth(skb, key);
1210 break;
1211 }
1212
1213 if (unlikely(err)) {
1214 kfree_skb(skb);
1215 return err;
1216 }
1217 }
1218
1219 consume_skb(skb);
1220 return 0;
1221 }
1222
1223 /* Execute the actions on the clone of the packet. The effect of the
1224 * execution does not affect the original 'skb' nor the original 'key'.
1225 *
1226 * The execution may be deferred in case the actions can not be executed
1227 * immediately.
1228 */
clone_execute(struct datapath * dp,struct sk_buff * skb,struct sw_flow_key * key,u32 recirc_id,const struct nlattr * actions,int len,bool last,bool clone_flow_key)1229 static int clone_execute(struct datapath *dp, struct sk_buff *skb,
1230 struct sw_flow_key *key, u32 recirc_id,
1231 const struct nlattr *actions, int len,
1232 bool last, bool clone_flow_key)
1233 {
1234 struct deferred_action *da;
1235 struct sw_flow_key *clone;
1236
1237 skb = last ? skb : skb_clone(skb, GFP_ATOMIC);
1238 if (!skb) {
1239 /* Out of memory, skip this action.
1240 */
1241 return 0;
1242 }
1243
1244 /* When clone_flow_key is false, the 'key' will not be change
1245 * by the actions, then the 'key' can be used directly.
1246 * Otherwise, try to clone key from the next recursion level of
1247 * 'flow_keys'. If clone is successful, execute the actions
1248 * without deferring.
1249 */
1250 clone = clone_flow_key ? clone_key(key) : key;
1251 if (clone) {
1252 int err = 0;
1253
1254 if (actions) { /* Sample action */
1255 if (clone_flow_key)
1256 __this_cpu_inc(exec_actions_level);
1257
1258 err = do_execute_actions(dp, skb, clone,
1259 actions, len);
1260
1261 if (clone_flow_key)
1262 __this_cpu_dec(exec_actions_level);
1263 } else { /* Recirc action */
1264 clone->recirc_id = recirc_id;
1265 ovs_dp_process_packet(skb, clone);
1266 }
1267 return err;
1268 }
1269
1270 /* Out of 'flow_keys' space. Defer actions */
1271 da = add_deferred_actions(skb, key, actions, len);
1272 if (da) {
1273 if (!actions) { /* Recirc action */
1274 key = &da->pkt_key;
1275 key->recirc_id = recirc_id;
1276 }
1277 } else {
1278 /* Out of per CPU action FIFO space. Drop the 'skb' and
1279 * log an error.
1280 */
1281 kfree_skb(skb);
1282
1283 if (net_ratelimit()) {
1284 if (actions) { /* Sample action */
1285 pr_warn("%s: deferred action limit reached, drop sample action\n",
1286 ovs_dp_name(dp));
1287 } else { /* Recirc action */
1288 pr_warn("%s: deferred action limit reached, drop recirc action\n",
1289 ovs_dp_name(dp));
1290 }
1291 }
1292 }
1293 return 0;
1294 }
1295
process_deferred_actions(struct datapath * dp)1296 static void process_deferred_actions(struct datapath *dp)
1297 {
1298 struct action_fifo *fifo = this_cpu_ptr(action_fifos);
1299
1300 /* Do not touch the FIFO in case there is no deferred actions. */
1301 if (action_fifo_is_empty(fifo))
1302 return;
1303
1304 /* Finishing executing all deferred actions. */
1305 do {
1306 struct deferred_action *da = action_fifo_get(fifo);
1307 struct sk_buff *skb = da->skb;
1308 struct sw_flow_key *key = &da->pkt_key;
1309 const struct nlattr *actions = da->actions;
1310 int actions_len = da->actions_len;
1311
1312 if (actions)
1313 do_execute_actions(dp, skb, key, actions, actions_len);
1314 else
1315 ovs_dp_process_packet(skb, key);
1316 } while (!action_fifo_is_empty(fifo));
1317
1318 /* Reset FIFO for the next packet. */
1319 action_fifo_init(fifo);
1320 }
1321
1322 /* Execute a list of actions against 'skb'. */
ovs_execute_actions(struct datapath * dp,struct sk_buff * skb,const struct sw_flow_actions * acts,struct sw_flow_key * key)1323 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
1324 const struct sw_flow_actions *acts,
1325 struct sw_flow_key *key)
1326 {
1327 int err, level;
1328
1329 level = __this_cpu_inc_return(exec_actions_level);
1330 if (unlikely(level > OVS_RECURSION_LIMIT)) {
1331 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
1332 ovs_dp_name(dp));
1333 kfree_skb(skb);
1334 err = -ENETDOWN;
1335 goto out;
1336 }
1337
1338 OVS_CB(skb)->acts_origlen = acts->orig_len;
1339 err = do_execute_actions(dp, skb, key,
1340 acts->actions, acts->actions_len);
1341
1342 if (level == 1)
1343 process_deferred_actions(dp);
1344
1345 out:
1346 __this_cpu_dec(exec_actions_level);
1347 return err;
1348 }
1349
action_fifos_init(void)1350 int action_fifos_init(void)
1351 {
1352 action_fifos = alloc_percpu(struct action_fifo);
1353 if (!action_fifos)
1354 return -ENOMEM;
1355
1356 flow_keys = alloc_percpu(struct action_flow_keys);
1357 if (!flow_keys) {
1358 free_percpu(action_fifos);
1359 return -ENOMEM;
1360 }
1361
1362 return 0;
1363 }
1364
action_fifos_exit(void)1365 void action_fifos_exit(void)
1366 {
1367 free_percpu(action_fifos);
1368 free_percpu(flow_keys);
1369 }
1370