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
59 u16 frag_max_size;
60 };
61
ipv4_l3mdev_skb(u16 flags)62 static inline bool ipv4_l3mdev_skb(u16 flags)
63 {
64 return !!(flags & IPSKB_L3SLAVE);
65 }
66
ip_hdrlen(const struct sk_buff * skb)67 static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
68 {
69 return ip_hdr(skb)->ihl * 4;
70 }
71
72 struct ipcm_cookie {
73 struct sockcm_cookie sockc;
74 __be32 addr;
75 int oif;
76 struct ip_options_rcu *opt;
77 __u8 ttl;
78 __s16 tos;
79 char priority;
80 __u16 gso_size;
81 };
82
ipcm_init(struct ipcm_cookie * ipcm)83 static inline void ipcm_init(struct ipcm_cookie *ipcm)
84 {
85 *ipcm = (struct ipcm_cookie) { .tos = -1 };
86 }
87
ipcm_init_sk(struct ipcm_cookie * ipcm,const struct inet_sock * inet)88 static inline void ipcm_init_sk(struct ipcm_cookie *ipcm,
89 const struct inet_sock *inet)
90 {
91 ipcm_init(ipcm);
92
93 ipcm->sockc.mark = inet->sk.sk_mark;
94 ipcm->sockc.tsflags = inet->sk.sk_tsflags;
95 ipcm->oif = inet->sk.sk_bound_dev_if;
96 ipcm->addr = inet->inet_saddr;
97 }
98
99 #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
100 #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
101
102 /* return enslaved device index if relevant */
inet_sdif(const struct sk_buff * skb)103 static inline int inet_sdif(const struct sk_buff *skb)
104 {
105 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
106 if (skb && ipv4_l3mdev_skb(IPCB(skb)->flags))
107 return IPCB(skb)->iif;
108 #endif
109 return 0;
110 }
111
112 /* Special input handler for packets caught by router alert option.
113 They are selected only by protocol field, and then processed likely
114 local ones; but only if someone wants them! Otherwise, router
115 not running rsvpd will kill RSVP.
116
117 It is user level problem, what it will make with them.
118 I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
119 but receiver should be enough clever f.e. to forward mtrace requests,
120 sent to multicast group to reach destination designated router.
121 */
122
123 struct ip_ra_chain {
124 struct ip_ra_chain __rcu *next;
125 struct sock *sk;
126 union {
127 void (*destructor)(struct sock *);
128 struct sock *saved_sk;
129 };
130 struct rcu_head rcu;
131 };
132
133 /* IP flags. */
134 #define IP_CE 0x8000 /* Flag: "Congestion" */
135 #define IP_DF 0x4000 /* Flag: "Don't Fragment" */
136 #define IP_MF 0x2000 /* Flag: "More Fragments" */
137 #define IP_OFFSET 0x1FFF /* "Fragment Offset" part */
138
139 #define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */
140
141 struct msghdr;
142 struct net_device;
143 struct packet_type;
144 struct rtable;
145 struct sockaddr;
146
147 int igmp_mc_init(void);
148
149 /*
150 * Functions provided by ip.c
151 */
152
153 int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
154 __be32 saddr, __be32 daddr,
155 struct ip_options_rcu *opt, u8 tos);
156 int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
157 struct net_device *orig_dev);
158 void ip_list_rcv(struct list_head *head, struct packet_type *pt,
159 struct net_device *orig_dev);
160 int ip_local_deliver(struct sk_buff *skb);
161 void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int proto);
162 int ip_mr_input(struct sk_buff *skb);
163 int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb);
164 int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb);
165 int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
166 int (*output)(struct net *, struct sock *, struct sk_buff *));
167
168 struct ip_fraglist_iter {
169 struct sk_buff *frag;
170 struct iphdr *iph;
171 int offset;
172 unsigned int hlen;
173 };
174
175 void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph,
176 unsigned int hlen, struct ip_fraglist_iter *iter);
177 void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter);
178
ip_fraglist_next(struct ip_fraglist_iter * iter)179 static inline struct sk_buff *ip_fraglist_next(struct ip_fraglist_iter *iter)
180 {
181 struct sk_buff *skb = iter->frag;
182
183 iter->frag = skb->next;
184 skb_mark_not_on_list(skb);
185
186 return skb;
187 }
188
189 struct ip_frag_state {
190 bool DF;
191 unsigned int hlen;
192 unsigned int ll_rs;
193 unsigned int mtu;
194 unsigned int left;
195 int offset;
196 int ptr;
197 __be16 not_last_frag;
198 };
199
200 void ip_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int ll_rs,
201 unsigned int mtu, bool DF, struct ip_frag_state *state);
202 struct sk_buff *ip_frag_next(struct sk_buff *skb,
203 struct ip_frag_state *state);
204
205 void ip_send_check(struct iphdr *ip);
206 int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
207 int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
208
209 int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
210 __u8 tos);
211 void ip_init(void);
212 int ip_append_data(struct sock *sk, struct flowi4 *fl4,
213 int getfrag(void *from, char *to, int offset, int len,
214 int odd, struct sk_buff *skb),
215 void *from, int len, int protolen,
216 struct ipcm_cookie *ipc,
217 struct rtable **rt,
218 unsigned int flags);
219 int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
220 struct sk_buff *skb);
221 ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
222 int offset, size_t size, int flags);
223 struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
224 struct sk_buff_head *queue,
225 struct inet_cork *cork);
226 int ip_send_skb(struct net *net, struct sk_buff *skb);
227 int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
228 void ip_flush_pending_frames(struct sock *sk);
229 struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4,
230 int getfrag(void *from, char *to, int offset,
231 int len, int odd, struct sk_buff *skb),
232 void *from, int length, int transhdrlen,
233 struct ipcm_cookie *ipc, struct rtable **rtp,
234 struct inet_cork *cork, unsigned int flags);
235
236 int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
237
ip_finish_skb(struct sock * sk,struct flowi4 * fl4)238 static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
239 {
240 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
241 }
242
get_rttos(struct ipcm_cookie * ipc,struct inet_sock * inet)243 static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
244 {
245 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
246 }
247
get_rtconn_flags(struct ipcm_cookie * ipc,struct sock * sk)248 static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
249 {
250 return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
251 }
252
253 /* datagram.c */
254 int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
255 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
256
257 void ip4_datagram_release_cb(struct sock *sk);
258
259 struct ip_reply_arg {
260 struct kvec iov[1];
261 int flags;
262 __wsum csum;
263 int csumoffset; /* u16 offset of csum in iov[0].iov_base */
264 /* -1 if not needed */
265 int bound_dev_if;
266 u8 tos;
267 kuid_t uid;
268 };
269
270 #define IP_REPLY_ARG_NOSRCCHECK 1
271
ip_reply_arg_flowi_flags(const struct ip_reply_arg * arg)272 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
273 {
274 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
275 }
276
277 void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
278 const struct ip_options *sopt,
279 __be32 daddr, __be32 saddr,
280 const struct ip_reply_arg *arg,
281 unsigned int len, u64 transmit_time);
282
283 #define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field)
284 #define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field)
285 #define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
286 #define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
287 #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_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 NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field)
290 #define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field)
291 #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
292 #define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
293
294 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct);
295 unsigned long snmp_fold_field(void __percpu *mib, int offt);
296 #if BITS_PER_LONG==32
297 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
298 size_t syncp_offset);
299 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
300 #else
snmp_get_cpu_field64(void __percpu * mib,int cpu,int offct,size_t syncp_offset)301 static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
302 size_t syncp_offset)
303 {
304 return snmp_get_cpu_field(mib, cpu, offct);
305
306 }
307
snmp_fold_field64(void __percpu * mib,int offt,size_t syncp_off)308 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
309 {
310 return snmp_fold_field(mib, offt);
311 }
312 #endif
313
314 #define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \
315 { \
316 int i, c; \
317 for_each_possible_cpu(c) { \
318 for (i = 0; stats_list[i].name; i++) \
319 buff64[i] += snmp_get_cpu_field64( \
320 mib_statistic, \
321 c, stats_list[i].entry, \
322 offset); \
323 } \
324 }
325
326 #define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \
327 { \
328 int i, c; \
329 for_each_possible_cpu(c) { \
330 for (i = 0; stats_list[i].name; i++) \
331 buff[i] += snmp_get_cpu_field( \
332 mib_statistic, \
333 c, stats_list[i].entry); \
334 } \
335 }
336
337 void inet_get_local_port_range(struct net *net, int *low, int *high);
338
339 #ifdef CONFIG_SYSCTL
inet_is_local_reserved_port(struct net * net,unsigned short port)340 static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
341 {
342 if (!net->ipv4.sysctl_local_reserved_ports)
343 return false;
344 return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
345 }
346
sysctl_dev_name_is_allowed(const char * name)347 static inline bool sysctl_dev_name_is_allowed(const char *name)
348 {
349 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0;
350 }
351
inet_port_requires_bind_service(struct net * net,unsigned short port)352 static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
353 {
354 return port < net->ipv4.sysctl_ip_prot_sock;
355 }
356
357 #else
inet_is_local_reserved_port(struct net * net,unsigned short port)358 static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
359 {
360 return false;
361 }
362
inet_port_requires_bind_service(struct net * net,unsigned short port)363 static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
364 {
365 return port < PROT_SOCK;
366 }
367 #endif
368
369 __be32 inet_current_timestamp(void);
370
371 /* From inetpeer.c */
372 extern int inet_peer_threshold;
373 extern int inet_peer_minttl;
374 extern int inet_peer_maxttl;
375
376 void ipfrag_init(void);
377
378 void ip_static_sysctl_init(void);
379
380 #define IP4_REPLY_MARK(net, mark) \
381 ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0)
382
ip_is_fragment(const struct iphdr * iph)383 static inline bool ip_is_fragment(const struct iphdr *iph)
384 {
385 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
386 }
387
388 #ifdef CONFIG_INET
389 #include <net/dst.h>
390
391 /* The function in 2.2 was invalid, producing wrong result for
392 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
393 static inline
ip_decrease_ttl(struct iphdr * iph)394 int ip_decrease_ttl(struct iphdr *iph)
395 {
396 u32 check = (__force u32)iph->check;
397 check += (__force u32)htons(0x0100);
398 iph->check = (__force __sum16)(check + (check>=0xFFFF));
399 return --iph->ttl;
400 }
401
ip_mtu_locked(const struct dst_entry * dst)402 static inline int ip_mtu_locked(const struct dst_entry *dst)
403 {
404 const struct rtable *rt = (const struct rtable *)dst;
405
406 return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU);
407 }
408
409 static inline
ip_dont_fragment(const struct sock * sk,const struct dst_entry * dst)410 int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
411 {
412 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
413
414 return pmtudisc == IP_PMTUDISC_DO ||
415 (pmtudisc == IP_PMTUDISC_WANT &&
416 !ip_mtu_locked(dst));
417 }
418
ip_sk_accept_pmtu(const struct sock * sk)419 static inline bool ip_sk_accept_pmtu(const struct sock *sk)
420 {
421 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
422 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
423 }
424
ip_sk_use_pmtu(const struct sock * sk)425 static inline bool ip_sk_use_pmtu(const struct sock *sk)
426 {
427 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
428 }
429
ip_sk_ignore_df(const struct sock * sk)430 static inline bool ip_sk_ignore_df(const struct sock *sk)
431 {
432 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
433 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
434 }
435
ip_dst_mtu_maybe_forward(const struct dst_entry * dst,bool forwarding)436 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
437 bool forwarding)
438 {
439 const struct rtable *rt = container_of(dst, struct rtable, dst);
440 struct net *net = dev_net(dst->dev);
441 unsigned int mtu;
442
443 if (net->ipv4.sysctl_ip_fwd_use_pmtu ||
444 ip_mtu_locked(dst) ||
445 !forwarding) {
446 mtu = rt->rt_pmtu;
447 if (mtu && time_before(jiffies, rt->dst.expires))
448 goto out;
449 }
450
451 /* 'forwarding = true' case should always honour route mtu */
452 mtu = dst_metric_raw(dst, RTAX_MTU);
453 if (mtu)
454 goto out;
455
456 mtu = READ_ONCE(dst->dev->mtu);
457
458 if (unlikely(ip_mtu_locked(dst))) {
459 if (rt->rt_uses_gateway && mtu > 576)
460 mtu = 576;
461 }
462
463 out:
464 mtu = min_t(unsigned int, mtu, IP_MAX_MTU);
465
466 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
467 }
468
ip_skb_dst_mtu(struct sock * sk,const struct sk_buff * skb)469 static inline unsigned int ip_skb_dst_mtu(struct sock *sk,
470 const struct sk_buff *skb)
471 {
472 unsigned int mtu;
473
474 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
475 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
476
477 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
478 }
479
480 mtu = min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU);
481 return mtu - lwtunnel_headroom(skb_dst(skb)->lwtstate, mtu);
482 }
483
484 struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx,
485 int fc_mx_len,
486 struct netlink_ext_ack *extack);
ip_fib_metrics_put(struct dst_metrics * fib_metrics)487 static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics)
488 {
489 if (fib_metrics != &dst_default_metrics &&
490 refcount_dec_and_test(&fib_metrics->refcnt))
491 kfree(fib_metrics);
492 }
493
494 /* ipv4 and ipv6 both use refcounted metrics if it is not the default */
495 static inline
ip_dst_init_metrics(struct dst_entry * dst,struct dst_metrics * fib_metrics)496 void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics)
497 {
498 dst_init_metrics(dst, fib_metrics->metrics, true);
499
500 if (fib_metrics != &dst_default_metrics) {
501 dst->_metrics |= DST_METRICS_REFCOUNTED;
502 refcount_inc(&fib_metrics->refcnt);
503 }
504 }
505
506 static inline
ip_dst_metrics_put(struct dst_entry * dst)507 void ip_dst_metrics_put(struct dst_entry *dst)
508 {
509 struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst);
510
511 if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt))
512 kfree(p);
513 }
514
515 u32 ip_idents_reserve(u32 hash, int segs);
516 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
517
ip_select_ident_segs(struct net * net,struct sk_buff * skb,struct sock * sk,int segs)518 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
519 struct sock *sk, int segs)
520 {
521 struct iphdr *iph = ip_hdr(skb);
522
523 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
524 /* This is only to work around buggy Windows95/2000
525 * VJ compression implementations. If the ID field
526 * does not change, they drop every other packet in
527 * a TCP stream using header compression.
528 */
529 if (sk && inet_sk(sk)->inet_daddr) {
530 iph->id = htons(inet_sk(sk)->inet_id);
531 inet_sk(sk)->inet_id += segs;
532 } else {
533 iph->id = 0;
534 }
535 } else {
536 __ip_select_ident(net, iph, segs);
537 }
538 }
539
ip_select_ident(struct net * net,struct sk_buff * skb,struct sock * sk)540 static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
541 struct sock *sk)
542 {
543 ip_select_ident_segs(net, skb, sk, 1);
544 }
545
inet_compute_pseudo(struct sk_buff * skb,int proto)546 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
547 {
548 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
549 skb->len, proto, 0);
550 }
551
552 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
553 * Equivalent to : flow->v4addrs.src = iph->saddr;
554 * flow->v4addrs.dst = iph->daddr;
555 */
iph_to_flow_copy_v4addrs(struct flow_keys * flow,const struct iphdr * iph)556 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
557 const struct iphdr *iph)
558 {
559 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
560 offsetof(typeof(flow->addrs), v4addrs.src) +
561 sizeof(flow->addrs.v4addrs.src));
562 memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs));
563 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
564 }
565
inet_gro_compute_pseudo(struct sk_buff * skb,int proto)566 static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto)
567 {
568 const struct iphdr *iph = skb_gro_network_header(skb);
569
570 return csum_tcpudp_nofold(iph->saddr, iph->daddr,
571 skb_gro_len(skb), proto, 0);
572 }
573
574 /*
575 * Map a multicast IP onto multicast MAC for type ethernet.
576 */
577
ip_eth_mc_map(__be32 naddr,char * buf)578 static inline void ip_eth_mc_map(__be32 naddr, char *buf)
579 {
580 __u32 addr=ntohl(naddr);
581 buf[0]=0x01;
582 buf[1]=0x00;
583 buf[2]=0x5e;
584 buf[5]=addr&0xFF;
585 addr>>=8;
586 buf[4]=addr&0xFF;
587 addr>>=8;
588 buf[3]=addr&0x7F;
589 }
590
591 /*
592 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
593 * Leave P_Key as 0 to be filled in by driver.
594 */
595
ip_ib_mc_map(__be32 naddr,const unsigned char * broadcast,char * buf)596 static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
597 {
598 __u32 addr;
599 unsigned char scope = broadcast[5] & 0xF;
600
601 buf[0] = 0; /* Reserved */
602 buf[1] = 0xff; /* Multicast QPN */
603 buf[2] = 0xff;
604 buf[3] = 0xff;
605 addr = ntohl(naddr);
606 buf[4] = 0xff;
607 buf[5] = 0x10 | scope; /* scope from broadcast address */
608 buf[6] = 0x40; /* IPv4 signature */
609 buf[7] = 0x1b;
610 buf[8] = broadcast[8]; /* P_Key */
611 buf[9] = broadcast[9];
612 buf[10] = 0;
613 buf[11] = 0;
614 buf[12] = 0;
615 buf[13] = 0;
616 buf[14] = 0;
617 buf[15] = 0;
618 buf[19] = addr & 0xff;
619 addr >>= 8;
620 buf[18] = addr & 0xff;
621 addr >>= 8;
622 buf[17] = addr & 0xff;
623 addr >>= 8;
624 buf[16] = addr & 0x0f;
625 }
626
ip_ipgre_mc_map(__be32 naddr,const unsigned char * broadcast,char * buf)627 static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
628 {
629 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0)
630 memcpy(buf, broadcast, 4);
631 else
632 memcpy(buf, &naddr, sizeof(naddr));
633 }
634
635 #if IS_ENABLED(CONFIG_IPV6)
636 #include <linux/ipv6.h>
637 #endif
638
inet_reset_saddr(struct sock * sk)639 static __inline__ void inet_reset_saddr(struct sock *sk)
640 {
641 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
642 #if IS_ENABLED(CONFIG_IPV6)
643 if (sk->sk_family == PF_INET6) {
644 struct ipv6_pinfo *np = inet6_sk(sk);
645
646 memset(&np->saddr, 0, sizeof(np->saddr));
647 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
648 }
649 #endif
650 }
651
652 #endif
653
ipv4_addr_hash(__be32 ip)654 static inline unsigned int ipv4_addr_hash(__be32 ip)
655 {
656 return (__force unsigned int) ip;
657 }
658
ipv4_portaddr_hash(const struct net * net,__be32 saddr,unsigned int port)659 static inline u32 ipv4_portaddr_hash(const struct net *net,
660 __be32 saddr,
661 unsigned int port)
662 {
663 return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port;
664 }
665
666 bool ip_call_ra_chain(struct sk_buff *skb);
667
668 /*
669 * Functions provided by ip_fragment.c
670 */
671
672 enum ip_defrag_users {
673 IP_DEFRAG_LOCAL_DELIVER,
674 IP_DEFRAG_CALL_RA_CHAIN,
675 IP_DEFRAG_CONNTRACK_IN,
676 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
677 IP_DEFRAG_CONNTRACK_OUT,
678 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
679 IP_DEFRAG_CONNTRACK_BRIDGE_IN,
680 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
681 IP_DEFRAG_VS_IN,
682 IP_DEFRAG_VS_OUT,
683 IP_DEFRAG_VS_FWD,
684 IP_DEFRAG_AF_PACKET,
685 IP_DEFRAG_MACVLAN,
686 };
687
688 /* Return true if the value of 'user' is between 'lower_bond'
689 * and 'upper_bond' inclusively.
690 */
ip_defrag_user_in_between(u32 user,enum ip_defrag_users lower_bond,enum ip_defrag_users upper_bond)691 static inline bool ip_defrag_user_in_between(u32 user,
692 enum ip_defrag_users lower_bond,
693 enum ip_defrag_users upper_bond)
694 {
695 return user >= lower_bond && user <= upper_bond;
696 }
697
698 int ip_defrag(struct net *net, struct sk_buff *skb, u32 user);
699 #ifdef CONFIG_INET
700 struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user);
701 #else
ip_check_defrag(struct net * net,struct sk_buff * skb,u32 user)702 static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
703 {
704 return skb;
705 }
706 #endif
707
708 /*
709 * Functions provided by ip_forward.c
710 */
711
712 int ip_forward(struct sk_buff *skb);
713
714 /*
715 * Functions provided by ip_options.c
716 */
717
718 void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
719 __be32 daddr, struct rtable *rt, int is_frag);
720
721 int __ip_options_echo(struct net *net, struct ip_options *dopt,
722 struct sk_buff *skb, const struct ip_options *sopt);
ip_options_echo(struct net * net,struct ip_options * dopt,struct sk_buff * skb)723 static inline int ip_options_echo(struct net *net, struct ip_options *dopt,
724 struct sk_buff *skb)
725 {
726 return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt);
727 }
728
729 void ip_options_fragment(struct sk_buff *skb);
730 int __ip_options_compile(struct net *net, struct ip_options *opt,
731 struct sk_buff *skb, __be32 *info);
732 int ip_options_compile(struct net *net, struct ip_options *opt,
733 struct sk_buff *skb);
734 int ip_options_get(struct net *net, struct ip_options_rcu **optp,
735 sockptr_t data, int optlen);
736 void ip_options_undo(struct ip_options *opt);
737 void ip_forward_options(struct sk_buff *skb);
738 int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev);
739
740 /*
741 * Functions provided by ip_sockglue.c
742 */
743
744 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
745 void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
746 struct sk_buff *skb, int tlen, int offset);
747 int ip_cmsg_send(struct sock *sk, struct msghdr *msg,
748 struct ipcm_cookie *ipc, bool allow_ipv6);
749 int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
750 unsigned int optlen);
751 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
752 int __user *optlen);
753 int ip_ra_control(struct sock *sk, unsigned char on,
754 void (*destructor)(struct sock *));
755
756 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
757 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
758 u32 info, u8 *payload);
759 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
760 u32 info);
761
ip_cmsg_recv(struct msghdr * msg,struct sk_buff * skb)762 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
763 {
764 ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0);
765 }
766
767 bool icmp_global_allow(void);
768 extern int sysctl_icmp_msgs_per_sec;
769 extern int sysctl_icmp_msgs_burst;
770
771 #ifdef CONFIG_PROC_FS
772 int ip_misc_proc_init(void);
773 #endif
774
775 int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family,
776 struct netlink_ext_ack *extack);
777
inetdev_valid_mtu(unsigned int mtu)778 static inline bool inetdev_valid_mtu(unsigned int mtu)
779 {
780 return likely(mtu >= IPV4_MIN_MTU);
781 }
782
783 void ip_sock_set_freebind(struct sock *sk);
784 int ip_sock_set_mtu_discover(struct sock *sk, int val);
785 void ip_sock_set_pktinfo(struct sock *sk);
786 void ip_sock_set_recverr(struct sock *sk);
787 void ip_sock_set_tos(struct sock *sk, int val);
788
789 #endif /* _IP_H */
790
