1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Definitions for the IP module.
8 *
9 * Version: @(#)ip.h 1.0.2 05/07/93
10 *
11 * Authors: Ross Biro
12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13 * Alan Cox, <gw4pts@gw4pts.ampr.org>
14 *
15 * Changes:
16 * Mike McLagan : Routing by source
17 */
18 #ifndef _IP_H
19 #define _IP_H
20
21 #include <linux/types.h>
22 #include <linux/ip.h>
23 #include <linux/in.h>
24 #include <linux/skbuff.h>
25 #include <linux/jhash.h>
26 #include <linux/sockptr.h>
27
28 #include <net/inet_sock.h>
29 #include <net/route.h>
30 #include <net/snmp.h>
31 #include <net/flow.h>
32 #include <net/flow_dissector.h>
33 #include <net/netns/hash.h>
34 #include <net/lwtunnel.h>
35
36 #define IPV4_MAX_PMTU 65535U /* RFC 2675, Section 5.1 */
37 #define IPV4_MIN_MTU 68 /* RFC 791 */
38
39 extern unsigned int sysctl_fib_sync_mem;
40 extern unsigned int sysctl_fib_sync_mem_min;
41 extern unsigned int sysctl_fib_sync_mem_max;
42
43 struct sock;
44
45 struct inet_skb_parm {
46 int iif;
47 struct ip_options opt; /* Compiled IP options */
48 u16 flags;
49
50 #define IPSKB_FORWARDED BIT(0)
51 #define IPSKB_XFRM_TUNNEL_SIZE BIT(1)
52 #define IPSKB_XFRM_TRANSFORMED BIT(2)
53 #define IPSKB_FRAG_COMPLETE BIT(3)
54 #define IPSKB_REROUTED BIT(4)
55 #define IPSKB_DOREDIRECT BIT(5)
56 #define IPSKB_FRAG_PMTU BIT(6)
57 #define IPSKB_L3SLAVE BIT(7)
58 #define IPSKB_NOPOLICY BIT(8)
59
60 u16 frag_max_size;
61 };
62
ipv4_l3mdev_skb(u16 flags)63 static inline bool ipv4_l3mdev_skb(u16 flags)
64 {
65 return !!(flags & IPSKB_L3SLAVE);
66 }
67
ip_hdrlen(const struct sk_buff * skb)68 static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
69 {
70 return ip_hdr(skb)->ihl * 4;
71 }
72
73 struct ipcm_cookie {
74 struct sockcm_cookie sockc;
75 __be32 addr;
76 int oif;
77 struct ip_options_rcu *opt;
78 __u8 ttl;
79 __s16 tos;
80 char priority;
81 __u16 gso_size;
82 };
83
ipcm_init(struct ipcm_cookie * ipcm)84 static inline void ipcm_init(struct ipcm_cookie *ipcm)
85 {
86 *ipcm = (struct ipcm_cookie) { .tos = -1 };
87 }
88
ipcm_init_sk(struct ipcm_cookie * ipcm,const struct inet_sock * inet)89 static inline void ipcm_init_sk(struct ipcm_cookie *ipcm,
90 const struct inet_sock *inet)
91 {
92 ipcm_init(ipcm);
93
94 ipcm->sockc.mark = inet->sk.sk_mark;
95 ipcm->sockc.tsflags = inet->sk.sk_tsflags;
96 ipcm->oif = inet->sk.sk_bound_dev_if;
97 ipcm->addr = inet->inet_saddr;
98 }
99
100 #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
101 #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
102
103 /* return enslaved device index if relevant */
inet_sdif(struct sk_buff * skb)104 static inline int inet_sdif(struct sk_buff *skb)
105 {
106 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
107 if (skb && ipv4_l3mdev_skb(IPCB(skb)->flags))
108 return IPCB(skb)->iif;
109 #endif
110 return 0;
111 }
112
113 /* Special input handler for packets caught by router alert option.
114 They are selected only by protocol field, and then processed likely
115 local ones; but only if someone wants them! Otherwise, router
116 not running rsvpd will kill RSVP.
117
118 It is user level problem, what it will make with them.
119 I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
120 but receiver should be enough clever f.e. to forward mtrace requests,
121 sent to multicast group to reach destination designated router.
122 */
123
124 struct ip_ra_chain {
125 struct ip_ra_chain __rcu *next;
126 struct sock *sk;
127 union {
128 void (*destructor)(struct sock *);
129 struct sock *saved_sk;
130 };
131 struct rcu_head rcu;
132 };
133
134 /* IP flags. */
135 #define IP_CE 0x8000 /* Flag: "Congestion" */
136 #define IP_DF 0x4000 /* Flag: "Don't Fragment" */
137 #define IP_MF 0x2000 /* Flag: "More Fragments" */
138 #define IP_OFFSET 0x1FFF /* "Fragment Offset" part */
139
140 #define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */
141
142 struct msghdr;
143 struct net_device;
144 struct packet_type;
145 struct rtable;
146 struct sockaddr;
147
148 int igmp_mc_init(void);
149
150 /*
151 * Functions provided by ip.c
152 */
153
154 int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
155 __be32 saddr, __be32 daddr,
156 struct ip_options_rcu *opt, u8 tos);
157 int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
158 struct net_device *orig_dev);
159 void ip_list_rcv(struct list_head *head, struct packet_type *pt,
160 struct net_device *orig_dev);
161 int ip_local_deliver(struct sk_buff *skb);
162 void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int proto);
163 int ip_mr_input(struct sk_buff *skb);
164 int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb);
165 int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb);
166 int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
167 int (*output)(struct net *, struct sock *, struct sk_buff *));
168
169 struct ip_fraglist_iter {
170 struct sk_buff *frag;
171 struct iphdr *iph;
172 int offset;
173 unsigned int hlen;
174 };
175
176 void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph,
177 unsigned int hlen, struct ip_fraglist_iter *iter);
178 void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter);
179
ip_fraglist_next(struct ip_fraglist_iter * iter)180 static inline struct sk_buff *ip_fraglist_next(struct ip_fraglist_iter *iter)
181 {
182 struct sk_buff *skb = iter->frag;
183
184 iter->frag = skb->next;
185 skb_mark_not_on_list(skb);
186
187 return skb;
188 }
189
190 struct ip_frag_state {
191 bool DF;
192 unsigned int hlen;
193 unsigned int ll_rs;
194 unsigned int mtu;
195 unsigned int left;
196 int offset;
197 int ptr;
198 __be16 not_last_frag;
199 };
200
201 void ip_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int ll_rs,
202 unsigned int mtu, bool DF, struct ip_frag_state *state);
203 struct sk_buff *ip_frag_next(struct sk_buff *skb,
204 struct ip_frag_state *state);
205
206 void ip_send_check(struct iphdr *ip);
207 int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
208 int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
209
210 int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
211 __u8 tos);
212 void ip_init(void);
213 int ip_append_data(struct sock *sk, struct flowi4 *fl4,
214 int getfrag(void *from, char *to, int offset, int len,
215 int odd, struct sk_buff *skb),
216 void *from, int len, int protolen,
217 struct ipcm_cookie *ipc,
218 struct rtable **rt,
219 unsigned int flags);
220 int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
221 struct sk_buff *skb);
222 ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
223 int offset, size_t size, int flags);
224 struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
225 struct sk_buff_head *queue,
226 struct inet_cork *cork);
227 int ip_send_skb(struct net *net, struct sk_buff *skb);
228 int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
229 void ip_flush_pending_frames(struct sock *sk);
230 struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4,
231 int getfrag(void *from, char *to, int offset,
232 int len, int odd, struct sk_buff *skb),
233 void *from, int length, int transhdrlen,
234 struct ipcm_cookie *ipc, struct rtable **rtp,
235 struct inet_cork *cork, unsigned int flags);
236
237 int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
238
ip_finish_skb(struct sock * sk,struct flowi4 * fl4)239 static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
240 {
241 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
242 }
243
get_rttos(struct ipcm_cookie * ipc,struct inet_sock * inet)244 static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
245 {
246 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
247 }
248
get_rtconn_flags(struct ipcm_cookie * ipc,struct sock * sk)249 static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
250 {
251 return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
252 }
253
254 /* datagram.c */
255 int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
256 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
257
258 void ip4_datagram_release_cb(struct sock *sk);
259
260 struct ip_reply_arg {
261 struct kvec iov[1];
262 int flags;
263 __wsum csum;
264 int csumoffset; /* u16 offset of csum in iov[0].iov_base */
265 /* -1 if not needed */
266 int bound_dev_if;
267 u8 tos;
268 kuid_t uid;
269 };
270
271 #define IP_REPLY_ARG_NOSRCCHECK 1
272
ip_reply_arg_flowi_flags(const struct ip_reply_arg * arg)273 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
274 {
275 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
276 }
277
278 void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
279 const struct ip_options *sopt,
280 __be32 daddr, __be32 saddr,
281 const struct ip_reply_arg *arg,
282 unsigned int len, u64 transmit_time);
283
284 #define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field)
285 #define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field)
286 #define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
287 #define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
288 #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
289 #define __IP_UPD_PO_STATS(net, field, val) __SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
290 #define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field)
291 #define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field)
292 #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
293 #define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
294
295 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct);
296 unsigned long snmp_fold_field(void __percpu *mib, int offt);
297 #if BITS_PER_LONG==32
298 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
299 size_t syncp_offset);
300 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
301 #else
snmp_get_cpu_field64(void __percpu * mib,int cpu,int offct,size_t syncp_offset)302 static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
303 size_t syncp_offset)
304 {
305 return snmp_get_cpu_field(mib, cpu, offct);
306
307 }
308
snmp_fold_field64(void __percpu * mib,int offt,size_t syncp_off)309 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
310 {
311 return snmp_fold_field(mib, offt);
312 }
313 #endif
314
315 #define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \
316 { \
317 int i, c; \
318 for_each_possible_cpu(c) { \
319 for (i = 0; stats_list[i].name; i++) \
320 buff64[i] += snmp_get_cpu_field64( \
321 mib_statistic, \
322 c, stats_list[i].entry, \
323 offset); \
324 } \
325 }
326
327 #define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \
328 { \
329 int i, c; \
330 for_each_possible_cpu(c) { \
331 for (i = 0; stats_list[i].name; i++) \
332 buff[i] += snmp_get_cpu_field( \
333 mib_statistic, \
334 c, stats_list[i].entry); \
335 } \
336 }
337
338 void inet_get_local_port_range(struct net *net, int *low, int *high);
339
340 #ifdef CONFIG_SYSCTL
inet_is_local_reserved_port(struct net * net,unsigned short port)341 static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
342 {
343 if (!net->ipv4.sysctl_local_reserved_ports)
344 return false;
345 return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
346 }
347
sysctl_dev_name_is_allowed(const char * name)348 static inline bool sysctl_dev_name_is_allowed(const char *name)
349 {
350 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0;
351 }
352
inet_port_requires_bind_service(struct net * net,unsigned short port)353 static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
354 {
355 return port < READ_ONCE(net->ipv4.sysctl_ip_prot_sock);
356 }
357
358 #else
inet_is_local_reserved_port(struct net * net,unsigned short port)359 static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
360 {
361 return false;
362 }
363
inet_port_requires_bind_service(struct net * net,unsigned short port)364 static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
365 {
366 return port < PROT_SOCK;
367 }
368 #endif
369
370 __be32 inet_current_timestamp(void);
371
372 /* From inetpeer.c */
373 extern int inet_peer_threshold;
374 extern int inet_peer_minttl;
375 extern int inet_peer_maxttl;
376
377 void ipfrag_init(void);
378
379 void ip_static_sysctl_init(void);
380
381 #define IP4_REPLY_MARK(net, mark) \
382 (READ_ONCE((net)->ipv4.sysctl_fwmark_reflect) ? (mark) : 0)
383
ip_is_fragment(const struct iphdr * iph)384 static inline bool ip_is_fragment(const struct iphdr *iph)
385 {
386 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
387 }
388
389 #ifdef CONFIG_INET
390 #include <net/dst.h>
391
392 /* The function in 2.2 was invalid, producing wrong result for
393 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
394 static inline
ip_decrease_ttl(struct iphdr * iph)395 int ip_decrease_ttl(struct iphdr *iph)
396 {
397 u32 check = (__force u32)iph->check;
398 check += (__force u32)htons(0x0100);
399 iph->check = (__force __sum16)(check + (check>=0xFFFF));
400 return --iph->ttl;
401 }
402
ip_mtu_locked(const struct dst_entry * dst)403 static inline int ip_mtu_locked(const struct dst_entry *dst)
404 {
405 const struct rtable *rt = (const struct rtable *)dst;
406
407 return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU);
408 }
409
410 static inline
ip_dont_fragment(const struct sock * sk,const struct dst_entry * dst)411 int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
412 {
413 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
414
415 return pmtudisc == IP_PMTUDISC_DO ||
416 (pmtudisc == IP_PMTUDISC_WANT &&
417 !ip_mtu_locked(dst));
418 }
419
ip_sk_accept_pmtu(const struct sock * sk)420 static inline bool ip_sk_accept_pmtu(const struct sock *sk)
421 {
422 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
423 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
424 }
425
ip_sk_use_pmtu(const struct sock * sk)426 static inline bool ip_sk_use_pmtu(const struct sock *sk)
427 {
428 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
429 }
430
ip_sk_ignore_df(const struct sock * sk)431 static inline bool ip_sk_ignore_df(const struct sock *sk)
432 {
433 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
434 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
435 }
436
ip_dst_mtu_maybe_forward(const struct dst_entry * dst,bool forwarding)437 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
438 bool forwarding)
439 {
440 struct net *net = dev_net(dst->dev);
441 unsigned int mtu;
442
443 if (READ_ONCE(net->ipv4.sysctl_ip_fwd_use_pmtu) ||
444 ip_mtu_locked(dst) ||
445 !forwarding)
446 return dst_mtu(dst);
447
448 /* 'forwarding = true' case should always honour route mtu */
449 mtu = dst_metric_raw(dst, RTAX_MTU);
450 if (!mtu)
451 mtu = min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU);
452
453 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
454 }
455
ip_skb_dst_mtu(struct sock * sk,const struct sk_buff * skb)456 static inline unsigned int ip_skb_dst_mtu(struct sock *sk,
457 const struct sk_buff *skb)
458 {
459 unsigned int mtu;
460
461 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
462 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
463
464 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
465 }
466
467 mtu = min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU);
468 return mtu - lwtunnel_headroom(skb_dst(skb)->lwtstate, mtu);
469 }
470
471 struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx,
472 int fc_mx_len,
473 struct netlink_ext_ack *extack);
ip_fib_metrics_put(struct dst_metrics * fib_metrics)474 static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics)
475 {
476 if (fib_metrics != &dst_default_metrics &&
477 refcount_dec_and_test(&fib_metrics->refcnt))
478 kfree(fib_metrics);
479 }
480
481 /* ipv4 and ipv6 both use refcounted metrics if it is not the default */
482 static inline
ip_dst_init_metrics(struct dst_entry * dst,struct dst_metrics * fib_metrics)483 void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics)
484 {
485 dst_init_metrics(dst, fib_metrics->metrics, true);
486
487 if (fib_metrics != &dst_default_metrics) {
488 dst->_metrics |= DST_METRICS_REFCOUNTED;
489 refcount_inc(&fib_metrics->refcnt);
490 }
491 }
492
493 static inline
ip_dst_metrics_put(struct dst_entry * dst)494 void ip_dst_metrics_put(struct dst_entry *dst)
495 {
496 struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst);
497
498 if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt))
499 kfree(p);
500 }
501
502 u32 ip_idents_reserve(u32 hash, int segs);
503 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
504
ip_select_ident_segs(struct net * net,struct sk_buff * skb,struct sock * sk,int segs)505 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
506 struct sock *sk, int segs)
507 {
508 struct iphdr *iph = ip_hdr(skb);
509
510 /* We had many attacks based on IPID, use the private
511 * generator as much as we can.
512 */
513 if (sk && inet_sk(sk)->inet_daddr) {
514 iph->id = htons(inet_sk(sk)->inet_id);
515 inet_sk(sk)->inet_id += segs;
516 return;
517 }
518 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
519 iph->id = 0;
520 } else {
521 /* Unfortunately we need the big hammer to get a suitable IPID */
522 __ip_select_ident(net, iph, segs);
523 }
524 }
525
ip_select_ident(struct net * net,struct sk_buff * skb,struct sock * sk)526 static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
527 struct sock *sk)
528 {
529 ip_select_ident_segs(net, skb, sk, 1);
530 }
531
inet_compute_pseudo(struct sk_buff * skb,int proto)532 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
533 {
534 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
535 skb->len, proto, 0);
536 }
537
538 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
539 * Equivalent to : flow->v4addrs.src = iph->saddr;
540 * flow->v4addrs.dst = iph->daddr;
541 */
iph_to_flow_copy_v4addrs(struct flow_keys * flow,const struct iphdr * iph)542 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
543 const struct iphdr *iph)
544 {
545 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
546 offsetof(typeof(flow->addrs), v4addrs.src) +
547 sizeof(flow->addrs.v4addrs.src));
548 memcpy(&flow->addrs.v4addrs, &iph->addrs, sizeof(flow->addrs.v4addrs));
549 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
550 }
551
inet_gro_compute_pseudo(struct sk_buff * skb,int proto)552 static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto)
553 {
554 const struct iphdr *iph = skb_gro_network_header(skb);
555
556 return csum_tcpudp_nofold(iph->saddr, iph->daddr,
557 skb_gro_len(skb), proto, 0);
558 }
559
560 /*
561 * Map a multicast IP onto multicast MAC for type ethernet.
562 */
563
ip_eth_mc_map(__be32 naddr,char * buf)564 static inline void ip_eth_mc_map(__be32 naddr, char *buf)
565 {
566 __u32 addr=ntohl(naddr);
567 buf[0]=0x01;
568 buf[1]=0x00;
569 buf[2]=0x5e;
570 buf[5]=addr&0xFF;
571 addr>>=8;
572 buf[4]=addr&0xFF;
573 addr>>=8;
574 buf[3]=addr&0x7F;
575 }
576
577 /*
578 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
579 * Leave P_Key as 0 to be filled in by driver.
580 */
581
ip_ib_mc_map(__be32 naddr,const unsigned char * broadcast,char * buf)582 static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
583 {
584 __u32 addr;
585 unsigned char scope = broadcast[5] & 0xF;
586
587 buf[0] = 0; /* Reserved */
588 buf[1] = 0xff; /* Multicast QPN */
589 buf[2] = 0xff;
590 buf[3] = 0xff;
591 addr = ntohl(naddr);
592 buf[4] = 0xff;
593 buf[5] = 0x10 | scope; /* scope from broadcast address */
594 buf[6] = 0x40; /* IPv4 signature */
595 buf[7] = 0x1b;
596 buf[8] = broadcast[8]; /* P_Key */
597 buf[9] = broadcast[9];
598 buf[10] = 0;
599 buf[11] = 0;
600 buf[12] = 0;
601 buf[13] = 0;
602 buf[14] = 0;
603 buf[15] = 0;
604 buf[19] = addr & 0xff;
605 addr >>= 8;
606 buf[18] = addr & 0xff;
607 addr >>= 8;
608 buf[17] = addr & 0xff;
609 addr >>= 8;
610 buf[16] = addr & 0x0f;
611 }
612
ip_ipgre_mc_map(__be32 naddr,const unsigned char * broadcast,char * buf)613 static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
614 {
615 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0)
616 memcpy(buf, broadcast, 4);
617 else
618 memcpy(buf, &naddr, sizeof(naddr));
619 }
620
621 #if IS_ENABLED(CONFIG_IPV6)
622 #include <linux/ipv6.h>
623 #endif
624
inet_reset_saddr(struct sock * sk)625 static __inline__ void inet_reset_saddr(struct sock *sk)
626 {
627 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
628 #if IS_ENABLED(CONFIG_IPV6)
629 if (sk->sk_family == PF_INET6) {
630 struct ipv6_pinfo *np = inet6_sk(sk);
631
632 memset(&np->saddr, 0, sizeof(np->saddr));
633 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
634 }
635 #endif
636 }
637
638 #endif
639
ipv4_addr_hash(__be32 ip)640 static inline unsigned int ipv4_addr_hash(__be32 ip)
641 {
642 return (__force unsigned int) ip;
643 }
644
ipv4_portaddr_hash(const struct net * net,__be32 saddr,unsigned int port)645 static inline u32 ipv4_portaddr_hash(const struct net *net,
646 __be32 saddr,
647 unsigned int port)
648 {
649 return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port;
650 }
651
652 bool ip_call_ra_chain(struct sk_buff *skb);
653
654 /*
655 * Functions provided by ip_fragment.c
656 */
657
658 enum ip_defrag_users {
659 IP_DEFRAG_LOCAL_DELIVER,
660 IP_DEFRAG_CALL_RA_CHAIN,
661 IP_DEFRAG_CONNTRACK_IN,
662 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
663 IP_DEFRAG_CONNTRACK_OUT,
664 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
665 IP_DEFRAG_CONNTRACK_BRIDGE_IN,
666 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
667 IP_DEFRAG_VS_IN,
668 IP_DEFRAG_VS_OUT,
669 IP_DEFRAG_VS_FWD,
670 IP_DEFRAG_AF_PACKET,
671 IP_DEFRAG_MACVLAN,
672 };
673
674 /* Return true if the value of 'user' is between 'lower_bond'
675 * and 'upper_bond' inclusively.
676 */
ip_defrag_user_in_between(u32 user,enum ip_defrag_users lower_bond,enum ip_defrag_users upper_bond)677 static inline bool ip_defrag_user_in_between(u32 user,
678 enum ip_defrag_users lower_bond,
679 enum ip_defrag_users upper_bond)
680 {
681 return user >= lower_bond && user <= upper_bond;
682 }
683
684 int ip_defrag(struct net *net, struct sk_buff *skb, u32 user);
685 #ifdef CONFIG_INET
686 struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user);
687 #else
ip_check_defrag(struct net * net,struct sk_buff * skb,u32 user)688 static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
689 {
690 return skb;
691 }
692 #endif
693
694 /*
695 * Functions provided by ip_forward.c
696 */
697
698 int ip_forward(struct sk_buff *skb);
699
700 /*
701 * Functions provided by ip_options.c
702 */
703
704 void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
705 __be32 daddr, struct rtable *rt, int is_frag);
706
707 int __ip_options_echo(struct net *net, struct ip_options *dopt,
708 struct sk_buff *skb, const struct ip_options *sopt);
ip_options_echo(struct net * net,struct ip_options * dopt,struct sk_buff * skb)709 static inline int ip_options_echo(struct net *net, struct ip_options *dopt,
710 struct sk_buff *skb)
711 {
712 return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt);
713 }
714
715 void ip_options_fragment(struct sk_buff *skb);
716 int __ip_options_compile(struct net *net, struct ip_options *opt,
717 struct sk_buff *skb, __be32 *info);
718 int ip_options_compile(struct net *net, struct ip_options *opt,
719 struct sk_buff *skb);
720 int ip_options_get(struct net *net, struct ip_options_rcu **optp,
721 sockptr_t data, int optlen);
722 void ip_options_undo(struct ip_options *opt);
723 void ip_forward_options(struct sk_buff *skb);
724 int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev);
725
726 /*
727 * Functions provided by ip_sockglue.c
728 */
729
730 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
731 void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
732 struct sk_buff *skb, int tlen, int offset);
733 int ip_cmsg_send(struct sock *sk, struct msghdr *msg,
734 struct ipcm_cookie *ipc, bool allow_ipv6);
735 int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
736 unsigned int optlen);
737 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
738 int __user *optlen);
739 int ip_ra_control(struct sock *sk, unsigned char on,
740 void (*destructor)(struct sock *));
741
742 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
743 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
744 u32 info, u8 *payload);
745 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
746 u32 info);
747
ip_cmsg_recv(struct msghdr * msg,struct sk_buff * skb)748 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
749 {
750 ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0);
751 }
752
753 bool icmp_global_allow(void);
754 extern int sysctl_icmp_msgs_per_sec;
755 extern int sysctl_icmp_msgs_burst;
756
757 #ifdef CONFIG_PROC_FS
758 int ip_misc_proc_init(void);
759 #endif
760
761 int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family,
762 struct netlink_ext_ack *extack);
763
inetdev_valid_mtu(unsigned int mtu)764 static inline bool inetdev_valid_mtu(unsigned int mtu)
765 {
766 return likely(mtu >= IPV4_MIN_MTU);
767 }
768
769 void ip_sock_set_freebind(struct sock *sk);
770 int ip_sock_set_mtu_discover(struct sock *sk, int val);
771 void ip_sock_set_pktinfo(struct sock *sk);
772 void ip_sock_set_recverr(struct sock *sk);
773 void ip_sock_set_tos(struct sock *sk, int val);
774
775 #endif /* _IP_H */
776