Line data Source code
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 :
35 : #define IPV4_MAX_PMTU 65535U /* RFC 2675, Section 5.1 */
36 : #define IPV4_MIN_MTU 68 /* RFC 791 */
37 :
38 : extern unsigned int sysctl_fib_sync_mem;
39 : extern unsigned int sysctl_fib_sync_mem_min;
40 : extern unsigned int sysctl_fib_sync_mem_max;
41 :
42 : struct sock;
43 :
44 : struct inet_skb_parm {
45 : int iif;
46 : struct ip_options opt; /* Compiled IP options */
47 : u16 flags;
48 :
49 : #define IPSKB_FORWARDED BIT(0)
50 : #define IPSKB_XFRM_TUNNEL_SIZE BIT(1)
51 : #define IPSKB_XFRM_TRANSFORMED BIT(2)
52 : #define IPSKB_FRAG_COMPLETE BIT(3)
53 : #define IPSKB_REROUTED BIT(4)
54 : #define IPSKB_DOREDIRECT BIT(5)
55 : #define IPSKB_FRAG_PMTU BIT(6)
56 : #define IPSKB_L3SLAVE BIT(7)
57 :
58 : u16 frag_max_size;
59 : };
60 :
61 0 : static inline bool ipv4_l3mdev_skb(u16 flags)
62 : {
63 0 : return !!(flags & IPSKB_L3SLAVE);
64 : }
65 :
66 0 : static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
67 : {
68 0 : return ip_hdr(skb)->ihl * 4;
69 : }
70 :
71 : struct ipcm_cookie {
72 : struct sockcm_cookie sockc;
73 : __be32 addr;
74 : int oif;
75 : struct ip_options_rcu *opt;
76 : __u8 ttl;
77 : __s16 tos;
78 : char priority;
79 : __u16 gso_size;
80 : };
81 :
82 14 : static inline void ipcm_init(struct ipcm_cookie *ipcm)
83 : {
84 14 : *ipcm = (struct ipcm_cookie) { .tos = -1 };
85 : }
86 :
87 14 : static inline void ipcm_init_sk(struct ipcm_cookie *ipcm,
88 : const struct inet_sock *inet)
89 : {
90 14 : ipcm_init(ipcm);
91 :
92 14 : ipcm->sockc.mark = inet->sk.sk_mark;
93 14 : ipcm->sockc.tsflags = inet->sk.sk_tsflags;
94 14 : ipcm->oif = inet->sk.sk_bound_dev_if;
95 14 : ipcm->addr = inet->inet_saddr;
96 : }
97 :
98 : #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
99 : #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
100 :
101 : /* return enslaved device index if relevant */
102 845 : static inline int inet_sdif(const struct sk_buff *skb)
103 : {
104 : #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
105 : if (skb && ipv4_l3mdev_skb(IPCB(skb)->flags))
106 : return IPCB(skb)->iif;
107 : #endif
108 845 : return 0;
109 : }
110 :
111 : /* Special input handler for packets caught by router alert option.
112 : They are selected only by protocol field, and then processed likely
113 : local ones; but only if someone wants them! Otherwise, router
114 : not running rsvpd will kill RSVP.
115 :
116 : It is user level problem, what it will make with them.
117 : I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
118 : but receiver should be enough clever f.e. to forward mtrace requests,
119 : sent to multicast group to reach destination designated router.
120 : */
121 :
122 : struct ip_ra_chain {
123 : struct ip_ra_chain __rcu *next;
124 : struct sock *sk;
125 : union {
126 : void (*destructor)(struct sock *);
127 : struct sock *saved_sk;
128 : };
129 : struct rcu_head rcu;
130 : };
131 :
132 : /* IP flags. */
133 : #define IP_CE 0x8000 /* Flag: "Congestion" */
134 : #define IP_DF 0x4000 /* Flag: "Don't Fragment" */
135 : #define IP_MF 0x2000 /* Flag: "More Fragments" */
136 : #define IP_OFFSET 0x1FFF /* "Fragment Offset" part */
137 :
138 : #define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */
139 :
140 : struct msghdr;
141 : struct net_device;
142 : struct packet_type;
143 : struct rtable;
144 : struct sockaddr;
145 :
146 : int igmp_mc_init(void);
147 :
148 : /*
149 : * Functions provided by ip.c
150 : */
151 :
152 : int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
153 : __be32 saddr, __be32 daddr,
154 : struct ip_options_rcu *opt, u8 tos);
155 : int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
156 : struct net_device *orig_dev);
157 : void ip_list_rcv(struct list_head *head, struct packet_type *pt,
158 : struct net_device *orig_dev);
159 : int ip_local_deliver(struct sk_buff *skb);
160 : void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int proto);
161 : int ip_mr_input(struct sk_buff *skb);
162 : int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb);
163 : int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb);
164 : int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
165 : int (*output)(struct net *, struct sock *, struct sk_buff *));
166 :
167 : struct ip_fraglist_iter {
168 : struct sk_buff *frag;
169 : struct iphdr *iph;
170 : int offset;
171 : unsigned int hlen;
172 : };
173 :
174 : void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph,
175 : unsigned int hlen, struct ip_fraglist_iter *iter);
176 : void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter);
177 :
178 0 : static inline struct sk_buff *ip_fraglist_next(struct ip_fraglist_iter *iter)
179 : {
180 0 : struct sk_buff *skb = iter->frag;
181 :
182 0 : iter->frag = skb->next;
183 0 : skb_mark_not_on_list(skb);
184 :
185 0 : return skb;
186 : }
187 :
188 : struct ip_frag_state {
189 : bool DF;
190 : unsigned int hlen;
191 : unsigned int ll_rs;
192 : unsigned int mtu;
193 : unsigned int left;
194 : int offset;
195 : int ptr;
196 : __be16 not_last_frag;
197 : };
198 :
199 : void ip_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int ll_rs,
200 : unsigned int mtu, bool DF, struct ip_frag_state *state);
201 : struct sk_buff *ip_frag_next(struct sk_buff *skb,
202 : struct ip_frag_state *state);
203 :
204 : void ip_send_check(struct iphdr *ip);
205 : int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
206 : int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
207 :
208 : int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
209 : __u8 tos);
210 : void ip_init(void);
211 : int ip_append_data(struct sock *sk, struct flowi4 *fl4,
212 : int getfrag(void *from, char *to, int offset, int len,
213 : int odd, struct sk_buff *skb),
214 : void *from, int len, int protolen,
215 : struct ipcm_cookie *ipc,
216 : struct rtable **rt,
217 : unsigned int flags);
218 : int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
219 : struct sk_buff *skb);
220 : ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
221 : int offset, size_t size, int flags);
222 : struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
223 : struct sk_buff_head *queue,
224 : struct inet_cork *cork);
225 : int ip_send_skb(struct net *net, struct sk_buff *skb);
226 : int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
227 : void ip_flush_pending_frames(struct sock *sk);
228 : struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4,
229 : int getfrag(void *from, char *to, int offset,
230 : int len, int odd, struct sk_buff *skb),
231 : void *from, int length, int transhdrlen,
232 : struct ipcm_cookie *ipc, struct rtable **rtp,
233 : struct inet_cork *cork, unsigned int flags);
234 :
235 : int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
236 :
237 0 : static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
238 : {
239 0 : return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
240 : }
241 :
242 14 : static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
243 : {
244 14 : return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
245 : }
246 :
247 0 : static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
248 : {
249 0 : return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
250 : }
251 :
252 : /* datagram.c */
253 : int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
254 : int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
255 :
256 : void ip4_datagram_release_cb(struct sock *sk);
257 :
258 : struct ip_reply_arg {
259 : struct kvec iov[1];
260 : int flags;
261 : __wsum csum;
262 : int csumoffset; /* u16 offset of csum in iov[0].iov_base */
263 : /* -1 if not needed */
264 : int bound_dev_if;
265 : u8 tos;
266 : kuid_t uid;
267 : };
268 :
269 : #define IP_REPLY_ARG_NOSRCCHECK 1
270 :
271 0 : static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
272 : {
273 0 : return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
274 : }
275 :
276 : void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
277 : const struct ip_options *sopt,
278 : __be32 daddr, __be32 saddr,
279 : const struct ip_reply_arg *arg,
280 : unsigned int len, u64 transmit_time);
281 :
282 : #define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field)
283 : #define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field)
284 : #define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
285 : #define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
286 : #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_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 NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field)
289 : #define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field)
290 : #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
291 : #define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
292 :
293 : u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct);
294 : unsigned long snmp_fold_field(void __percpu *mib, int offt);
295 : #if BITS_PER_LONG==32
296 : u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
297 : size_t syncp_offset);
298 : u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
299 : #else
300 0 : static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
301 : size_t syncp_offset)
302 : {
303 0 : return snmp_get_cpu_field(mib, cpu, offct);
304 :
305 : }
306 :
307 0 : static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
308 : {
309 0 : return snmp_fold_field(mib, offt);
310 : }
311 : #endif
312 :
313 : #define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \
314 : { \
315 : int i, c; \
316 : for_each_possible_cpu(c) { \
317 : for (i = 0; stats_list[i].name; i++) \
318 : buff64[i] += snmp_get_cpu_field64( \
319 : mib_statistic, \
320 : c, stats_list[i].entry, \
321 : offset); \
322 : } \
323 : }
324 :
325 : #define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \
326 : { \
327 : int i, c; \
328 : for_each_possible_cpu(c) { \
329 : for (i = 0; stats_list[i].name; i++) \
330 : buff[i] += snmp_get_cpu_field( \
331 : mib_statistic, \
332 : c, stats_list[i].entry); \
333 : } \
334 : }
335 :
336 : void inet_get_local_port_range(struct net *net, int *low, int *high);
337 :
338 : #ifdef CONFIG_SYSCTL
339 33 : static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
340 : {
341 33 : if (!net->ipv4.sysctl_local_reserved_ports)
342 : return false;
343 33 : return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
344 : }
345 :
346 2 : static inline bool sysctl_dev_name_is_allowed(const char *name)
347 : {
348 2 : return strcmp(name, "default") != 0 && strcmp(name, "all") != 0;
349 : }
350 :
351 5 : static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
352 : {
353 5 : return port < net->ipv4.sysctl_ip_prot_sock;
354 : }
355 :
356 : #else
357 : static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
358 : {
359 : return false;
360 : }
361 :
362 : static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
363 : {
364 : return port < PROT_SOCK;
365 : }
366 : #endif
367 :
368 : __be32 inet_current_timestamp(void);
369 :
370 : /* From inetpeer.c */
371 : extern int inet_peer_threshold;
372 : extern int inet_peer_minttl;
373 : extern int inet_peer_maxttl;
374 :
375 : void ipfrag_init(void);
376 :
377 : void ip_static_sysctl_init(void);
378 :
379 : #define IP4_REPLY_MARK(net, mark) \
380 : ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0)
381 :
382 1568 : static inline bool ip_is_fragment(const struct iphdr *iph)
383 : {
384 1568 : return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
385 : }
386 :
387 : #ifdef CONFIG_INET
388 : #include <net/dst.h>
389 :
390 : /* The function in 2.2 was invalid, producing wrong result for
391 : * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
392 : static inline
393 0 : int ip_decrease_ttl(struct iphdr *iph)
394 : {
395 0 : u32 check = (__force u32)iph->check;
396 0 : check += (__force u32)htons(0x0100);
397 0 : iph->check = (__force __sum16)(check + (check>=0xFFFF));
398 0 : return --iph->ttl;
399 : }
400 :
401 1868 : static inline int ip_mtu_locked(const struct dst_entry *dst)
402 : {
403 1868 : const struct rtable *rt = (const struct rtable *)dst;
404 :
405 3736 : return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU);
406 : }
407 :
408 : static inline
409 444 : int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
410 : {
411 444 : u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
412 :
413 444 : return pmtudisc == IP_PMTUDISC_DO ||
414 444 : (pmtudisc == IP_PMTUDISC_WANT &&
415 444 : !ip_mtu_locked(dst));
416 : }
417 :
418 0 : static inline bool ip_sk_accept_pmtu(const struct sock *sk)
419 : {
420 0 : return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
421 0 : inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
422 : }
423 :
424 454 : static inline bool ip_sk_use_pmtu(const struct sock *sk)
425 : {
426 454 : return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
427 : }
428 :
429 28 : static inline bool ip_sk_ignore_df(const struct sock *sk)
430 : {
431 28 : return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
432 0 : inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
433 : }
434 :
435 444 : static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
436 : bool forwarding)
437 : {
438 444 : struct net *net = dev_net(dst->dev);
439 444 : unsigned int mtu;
440 :
441 888 : if (net->ipv4.sysctl_ip_fwd_use_pmtu ||
442 888 : ip_mtu_locked(dst) ||
443 : !forwarding)
444 444 : return dst_mtu(dst);
445 :
446 : /* 'forwarding = true' case should always honour route mtu */
447 0 : mtu = dst_metric_raw(dst, RTAX_MTU);
448 0 : if (mtu)
449 : return mtu;
450 :
451 0 : return min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU);
452 : }
453 :
454 444 : static inline unsigned int ip_skb_dst_mtu(struct sock *sk,
455 : const struct sk_buff *skb)
456 : {
457 444 : if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
458 444 : bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
459 :
460 444 : return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
461 : }
462 :
463 0 : return min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU);
464 : }
465 :
466 : struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx,
467 : int fc_mx_len,
468 : struct netlink_ext_ack *extack);
469 5 : static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics)
470 : {
471 5 : if (fib_metrics != &dst_default_metrics &&
472 0 : refcount_dec_and_test(&fib_metrics->refcnt))
473 0 : kfree(fib_metrics);
474 5 : }
475 :
476 : /* ipv4 and ipv6 both use refcounted metrics if it is not the default */
477 : static inline
478 7 : void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics)
479 : {
480 7 : dst_init_metrics(dst, fib_metrics->metrics, true);
481 :
482 7 : if (fib_metrics != &dst_default_metrics) {
483 0 : dst->_metrics |= DST_METRICS_REFCOUNTED;
484 0 : refcount_inc(&fib_metrics->refcnt);
485 : }
486 7 : }
487 :
488 : static inline
489 8 : void ip_dst_metrics_put(struct dst_entry *dst)
490 : {
491 8 : struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst);
492 :
493 8 : if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt))
494 0 : kfree(p);
495 8 : }
496 :
497 : u32 ip_idents_reserve(u32 hash, int segs);
498 : void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
499 :
500 440 : static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
501 : struct sock *sk, int segs)
502 : {
503 440 : struct iphdr *iph = ip_hdr(skb);
504 :
505 440 : if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
506 : /* This is only to work around buggy Windows95/2000
507 : * VJ compression implementations. If the ID field
508 : * does not change, they drop every other packet in
509 : * a TCP stream using header compression.
510 : */
511 426 : if (sk && inet_sk(sk)->inet_daddr) {
512 426 : iph->id = htons(inet_sk(sk)->inet_id);
513 426 : inet_sk(sk)->inet_id += segs;
514 : } else {
515 0 : iph->id = 0;
516 : }
517 : } else {
518 14 : __ip_select_ident(net, iph, segs);
519 : }
520 440 : }
521 :
522 14 : static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
523 : struct sock *sk)
524 : {
525 14 : ip_select_ident_segs(net, skb, sk, 1);
526 0 : }
527 :
528 0 : static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
529 : {
530 0 : return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
531 : skb->len, proto, 0);
532 : }
533 :
534 : /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
535 : * Equivalent to : flow->v4addrs.src = iph->saddr;
536 : * flow->v4addrs.dst = iph->daddr;
537 : */
538 : static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
539 : const struct iphdr *iph)
540 : {
541 : BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
542 : offsetof(typeof(flow->addrs), v4addrs.src) +
543 : sizeof(flow->addrs.v4addrs.src));
544 : memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs));
545 : flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
546 : }
547 :
548 707 : static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto)
549 : {
550 707 : const struct iphdr *iph = skb_gro_network_header(skb);
551 :
552 707 : return csum_tcpudp_nofold(iph->saddr, iph->daddr,
553 : skb_gro_len(skb), proto, 0);
554 : }
555 :
556 : /*
557 : * Map a multicast IP onto multicast MAC for type ethernet.
558 : */
559 :
560 1 : static inline void ip_eth_mc_map(__be32 naddr, char *buf)
561 : {
562 1 : __u32 addr=ntohl(naddr);
563 1 : buf[0]=0x01;
564 1 : buf[1]=0x00;
565 1 : buf[2]=0x5e;
566 1 : buf[5]=addr&0xFF;
567 1 : addr>>=8;
568 1 : buf[4]=addr&0xFF;
569 1 : addr>>=8;
570 1 : buf[3]=addr&0x7F;
571 : }
572 :
573 : /*
574 : * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
575 : * Leave P_Key as 0 to be filled in by driver.
576 : */
577 :
578 0 : static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
579 : {
580 0 : __u32 addr;
581 0 : unsigned char scope = broadcast[5] & 0xF;
582 :
583 0 : buf[0] = 0; /* Reserved */
584 0 : buf[1] = 0xff; /* Multicast QPN */
585 0 : buf[2] = 0xff;
586 0 : buf[3] = 0xff;
587 0 : addr = ntohl(naddr);
588 0 : buf[4] = 0xff;
589 0 : buf[5] = 0x10 | scope; /* scope from broadcast address */
590 0 : buf[6] = 0x40; /* IPv4 signature */
591 0 : buf[7] = 0x1b;
592 0 : buf[8] = broadcast[8]; /* P_Key */
593 0 : buf[9] = broadcast[9];
594 0 : buf[10] = 0;
595 0 : buf[11] = 0;
596 0 : buf[12] = 0;
597 0 : buf[13] = 0;
598 0 : buf[14] = 0;
599 0 : buf[15] = 0;
600 0 : buf[19] = addr & 0xff;
601 0 : addr >>= 8;
602 0 : buf[18] = addr & 0xff;
603 0 : addr >>= 8;
604 0 : buf[17] = addr & 0xff;
605 0 : addr >>= 8;
606 0 : buf[16] = addr & 0x0f;
607 0 : }
608 :
609 0 : static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
610 : {
611 0 : if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0)
612 0 : memcpy(buf, broadcast, 4);
613 : else
614 0 : memcpy(buf, &naddr, sizeof(naddr));
615 : }
616 :
617 : #if IS_ENABLED(CONFIG_IPV6)
618 : #include <linux/ipv6.h>
619 : #endif
620 :
621 0 : static __inline__ void inet_reset_saddr(struct sock *sk)
622 : {
623 0 : inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
624 : #if IS_ENABLED(CONFIG_IPV6)
625 : if (sk->sk_family == PF_INET6) {
626 : struct ipv6_pinfo *np = inet6_sk(sk);
627 :
628 : memset(&np->saddr, 0, sizeof(np->saddr));
629 : memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
630 : }
631 : #endif
632 0 : }
633 :
634 : #endif
635 :
636 7 : static inline unsigned int ipv4_addr_hash(__be32 ip)
637 : {
638 7 : return (__force unsigned int) ip;
639 : }
640 :
641 109 : static inline u32 ipv4_portaddr_hash(const struct net *net,
642 : __be32 saddr,
643 : unsigned int port)
644 : {
645 109 : return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port;
646 : }
647 :
648 : bool ip_call_ra_chain(struct sk_buff *skb);
649 :
650 : /*
651 : * Functions provided by ip_fragment.c
652 : */
653 :
654 : enum ip_defrag_users {
655 : IP_DEFRAG_LOCAL_DELIVER,
656 : IP_DEFRAG_CALL_RA_CHAIN,
657 : IP_DEFRAG_CONNTRACK_IN,
658 : __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
659 : IP_DEFRAG_CONNTRACK_OUT,
660 : __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
661 : IP_DEFRAG_CONNTRACK_BRIDGE_IN,
662 : __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
663 : IP_DEFRAG_VS_IN,
664 : IP_DEFRAG_VS_OUT,
665 : IP_DEFRAG_VS_FWD,
666 : IP_DEFRAG_AF_PACKET,
667 : IP_DEFRAG_MACVLAN,
668 : };
669 :
670 : /* Return true if the value of 'user' is between 'lower_bond'
671 : * and 'upper_bond' inclusively.
672 : */
673 0 : static inline bool ip_defrag_user_in_between(u32 user,
674 : enum ip_defrag_users lower_bond,
675 : enum ip_defrag_users upper_bond)
676 : {
677 0 : return user >= lower_bond && user <= upper_bond;
678 : }
679 :
680 : int ip_defrag(struct net *net, struct sk_buff *skb, u32 user);
681 : #ifdef CONFIG_INET
682 : struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user);
683 : #else
684 : static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
685 : {
686 : return skb;
687 : }
688 : #endif
689 :
690 : /*
691 : * Functions provided by ip_forward.c
692 : */
693 :
694 : int ip_forward(struct sk_buff *skb);
695 :
696 : /*
697 : * Functions provided by ip_options.c
698 : */
699 :
700 : void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
701 : __be32 daddr, struct rtable *rt, int is_frag);
702 :
703 : int __ip_options_echo(struct net *net, struct ip_options *dopt,
704 : struct sk_buff *skb, const struct ip_options *sopt);
705 0 : static inline int ip_options_echo(struct net *net, struct ip_options *dopt,
706 : struct sk_buff *skb)
707 : {
708 0 : return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt);
709 : }
710 :
711 : void ip_options_fragment(struct sk_buff *skb);
712 : int __ip_options_compile(struct net *net, struct ip_options *opt,
713 : struct sk_buff *skb, __be32 *info);
714 : int ip_options_compile(struct net *net, struct ip_options *opt,
715 : struct sk_buff *skb);
716 : int ip_options_get(struct net *net, struct ip_options_rcu **optp,
717 : sockptr_t data, int optlen);
718 : void ip_options_undo(struct ip_options *opt);
719 : void ip_forward_options(struct sk_buff *skb);
720 : int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev);
721 :
722 : /*
723 : * Functions provided by ip_sockglue.c
724 : */
725 :
726 : void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
727 : void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
728 : struct sk_buff *skb, int tlen, int offset);
729 : int ip_cmsg_send(struct sock *sk, struct msghdr *msg,
730 : struct ipcm_cookie *ipc, bool allow_ipv6);
731 : int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
732 : unsigned int optlen);
733 : int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
734 : int __user *optlen);
735 : int ip_ra_control(struct sock *sk, unsigned char on,
736 : void (*destructor)(struct sock *));
737 :
738 : int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
739 : void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
740 : u32 info, u8 *payload);
741 : void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
742 : u32 info);
743 :
744 0 : static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
745 : {
746 0 : ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0);
747 0 : }
748 :
749 : bool icmp_global_allow(void);
750 : extern int sysctl_icmp_msgs_per_sec;
751 : extern int sysctl_icmp_msgs_burst;
752 :
753 : #ifdef CONFIG_PROC_FS
754 : int ip_misc_proc_init(void);
755 : #endif
756 :
757 : int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family,
758 : struct netlink_ext_ack *extack);
759 :
760 16 : static inline bool inetdev_valid_mtu(unsigned int mtu)
761 : {
762 16 : return likely(mtu >= IPV4_MIN_MTU);
763 : }
764 :
765 : void ip_sock_set_freebind(struct sock *sk);
766 : int ip_sock_set_mtu_discover(struct sock *sk, int val);
767 : void ip_sock_set_pktinfo(struct sock *sk);
768 : void ip_sock_set_recverr(struct sock *sk);
769 : void ip_sock_set_tos(struct sock *sk, int val);
770 :
771 : #endif /* _IP_H */
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