1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Definitions for the IP module.
7 *
8 * Version: @(#)ip.h 1.0.2 05/07/93
9 *
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Alan Cox, <gw4pts@gw4pts.ampr.org>
13 *
14 * Changes:
15 * Mike McLagan : Routing by source
16 *
17 * This program is free software; you can redistribute it and/or
18 * modify it under the terms of the GNU General Public License
19 * as published by the Free Software Foundation; either version
20 * 2 of the License, or (at your option) any later version.
21 */
22 #ifndef _IP_H
23 #define _IP_H
24
25 #include <linux/types.h>
26 #include <linux/ip.h>
27 #include <linux/in.h>
28 #include <linux/skbuff.h>
29
30 #include <net/inet_sock.h>
31 #include <net/route.h>
32 #include <net/snmp.h>
33 #include <net/flow.h>
34 #include <net/flow_dissector.h>
35
36 #define IPV4_MIN_MTU 68 /* RFC 791 */
37
38 struct sock;
39
40 struct inet_skb_parm {
41 int iif;
42 struct ip_options opt; /* Compiled IP options */
43 u16 flags;
44
45 #define IPSKB_FORWARDED BIT(0)
46 #define IPSKB_XFRM_TUNNEL_SIZE BIT(1)
47 #define IPSKB_XFRM_TRANSFORMED BIT(2)
48 #define IPSKB_FRAG_COMPLETE BIT(3)
49 #define IPSKB_REROUTED BIT(4)
50 #define IPSKB_DOREDIRECT BIT(5)
51 #define IPSKB_FRAG_PMTU BIT(6)
52 #define IPSKB_L3SLAVE BIT(7)
53
54 u16 frag_max_size;
55 };
56
ipv4_l3mdev_skb(u16 flags)57 static inline bool ipv4_l3mdev_skb(u16 flags)
58 {
59 return !!(flags & IPSKB_L3SLAVE);
60 }
61
ip_hdrlen(const struct sk_buff * skb)62 static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
63 {
64 return ip_hdr(skb)->ihl * 4;
65 }
66
67 struct ipcm_cookie {
68 struct sockcm_cookie sockc;
69 __be32 addr;
70 int oif;
71 struct ip_options_rcu *opt;
72 __u8 tx_flags;
73 __u8 ttl;
74 __s16 tos;
75 char priority;
76 };
77
78 #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
79 #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
80
81 struct ip_ra_chain {
82 struct ip_ra_chain __rcu *next;
83 struct sock *sk;
84 union {
85 void (*destructor)(struct sock *);
86 struct sock *saved_sk;
87 };
88 struct rcu_head rcu;
89 };
90
91 extern struct ip_ra_chain __rcu *ip_ra_chain;
92
93 /* IP flags. */
94 #define IP_CE 0x8000 /* Flag: "Congestion" */
95 #define IP_DF 0x4000 /* Flag: "Don't Fragment" */
96 #define IP_MF 0x2000 /* Flag: "More Fragments" */
97 #define IP_OFFSET 0x1FFF /* "Fragment Offset" part */
98
99 #define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */
100
101 struct msghdr;
102 struct net_device;
103 struct packet_type;
104 struct rtable;
105 struct sockaddr;
106
107 int igmp_mc_init(void);
108
109 /*
110 * Functions provided by ip.c
111 */
112
113 int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
114 __be32 saddr, __be32 daddr,
115 struct ip_options_rcu *opt);
116 int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
117 struct net_device *orig_dev);
118 int ip_local_deliver(struct sk_buff *skb);
119 int ip_mr_input(struct sk_buff *skb);
120 int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb);
121 int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb);
122 int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
123 int (*output)(struct net *, struct sock *, struct sk_buff *));
124 void ip_send_check(struct iphdr *ip);
125 int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
126 int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
127
128 int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
129 void ip_init(void);
130 int ip_append_data(struct sock *sk, struct flowi4 *fl4,
131 int getfrag(void *from, char *to, int offset, int len,
132 int odd, struct sk_buff *skb),
133 void *from, int len, int protolen,
134 struct ipcm_cookie *ipc,
135 struct rtable **rt,
136 unsigned int flags);
137 int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
138 struct sk_buff *skb);
139 ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
140 int offset, size_t size, int flags);
141 struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
142 struct sk_buff_head *queue,
143 struct inet_cork *cork);
144 int ip_send_skb(struct net *net, struct sk_buff *skb);
145 int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
146 void ip_flush_pending_frames(struct sock *sk);
147 struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4,
148 int getfrag(void *from, char *to, int offset,
149 int len, int odd, struct sk_buff *skb),
150 void *from, int length, int transhdrlen,
151 struct ipcm_cookie *ipc, struct rtable **rtp,
152 unsigned int flags);
153
ip_finish_skb(struct sock * sk,struct flowi4 * fl4)154 static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
155 {
156 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
157 }
158
get_rttos(struct ipcm_cookie * ipc,struct inet_sock * inet)159 static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
160 {
161 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
162 }
163
get_rtconn_flags(struct ipcm_cookie * ipc,struct sock * sk)164 static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
165 {
166 return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
167 }
168
169 /* datagram.c */
170 int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
171 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
172
173 void ip4_datagram_release_cb(struct sock *sk);
174
175 struct ip_reply_arg {
176 struct kvec iov[1];
177 int flags;
178 __wsum csum;
179 int csumoffset; /* u16 offset of csum in iov[0].iov_base */
180 /* -1 if not needed */
181 int bound_dev_if;
182 u8 tos;
183 kuid_t uid;
184 };
185
186 #define IP_REPLY_ARG_NOSRCCHECK 1
187
ip_reply_arg_flowi_flags(const struct ip_reply_arg * arg)188 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
189 {
190 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
191 }
192
193 void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
194 const struct ip_options *sopt,
195 __be32 daddr, __be32 saddr,
196 const struct ip_reply_arg *arg,
197 unsigned int len);
198
199 #define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field)
200 #define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field)
201 #define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
202 #define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
203 #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
204 #define __IP_UPD_PO_STATS(net, field, val) __SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
205 #define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field)
206 #define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field)
207 #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
208 #define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
209
210 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct);
211 unsigned long snmp_fold_field(void __percpu *mib, int offt);
212 #if BITS_PER_LONG==32
213 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
214 size_t syncp_offset);
215 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
216 #else
snmp_get_cpu_field64(void __percpu * mib,int cpu,int offct,size_t syncp_offset)217 static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
218 size_t syncp_offset)
219 {
220 return snmp_get_cpu_field(mib, cpu, offct);
221
222 }
223
snmp_fold_field64(void __percpu * mib,int offt,size_t syncp_off)224 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
225 {
226 return snmp_fold_field(mib, offt);
227 }
228 #endif
229
230 #define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \
231 { \
232 int i, c; \
233 for_each_possible_cpu(c) { \
234 for (i = 0; stats_list[i].name; i++) \
235 buff64[i] += snmp_get_cpu_field64( \
236 mib_statistic, \
237 c, stats_list[i].entry, \
238 offset); \
239 } \
240 }
241
242 #define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \
243 { \
244 int i, c; \
245 for_each_possible_cpu(c) { \
246 for (i = 0; stats_list[i].name; i++) \
247 buff[i] += snmp_get_cpu_field( \
248 mib_statistic, \
249 c, stats_list[i].entry); \
250 } \
251 }
252
253 void inet_get_local_port_range(struct net *net, int *low, int *high);
254
255 #ifdef CONFIG_SYSCTL
inet_is_local_reserved_port(struct net * net,int port)256 static inline int inet_is_local_reserved_port(struct net *net, int port)
257 {
258 if (!net->ipv4.sysctl_local_reserved_ports)
259 return 0;
260 return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
261 }
262
sysctl_dev_name_is_allowed(const char * name)263 static inline bool sysctl_dev_name_is_allowed(const char *name)
264 {
265 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0;
266 }
267
268 #else
inet_is_local_reserved_port(struct net * net,int port)269 static inline int inet_is_local_reserved_port(struct net *net, int port)
270 {
271 return 0;
272 }
273 #endif
274
275 __be32 inet_current_timestamp(void);
276
277 /* From inetpeer.c */
278 extern int inet_peer_threshold;
279 extern int inet_peer_minttl;
280 extern int inet_peer_maxttl;
281
282 void ipfrag_init(void);
283
284 void ip_static_sysctl_init(void);
285
286 #define IP4_REPLY_MARK(net, mark) \
287 ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0)
288
ip_is_fragment(const struct iphdr * iph)289 static inline bool ip_is_fragment(const struct iphdr *iph)
290 {
291 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
292 }
293
294 #ifdef CONFIG_INET
295 #include <net/dst.h>
296
297 /* The function in 2.2 was invalid, producing wrong result for
298 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
299 static inline
ip_decrease_ttl(struct iphdr * iph)300 int ip_decrease_ttl(struct iphdr *iph)
301 {
302 u32 check = (__force u32)iph->check;
303 check += (__force u32)htons(0x0100);
304 iph->check = (__force __sum16)(check + (check>=0xFFFF));
305 return --iph->ttl;
306 }
307
308 static inline
ip_dont_fragment(const struct sock * sk,const struct dst_entry * dst)309 int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
310 {
311 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
312
313 return pmtudisc == IP_PMTUDISC_DO ||
314 (pmtudisc == IP_PMTUDISC_WANT &&
315 !(dst_metric_locked(dst, RTAX_MTU)));
316 }
317
ip_sk_accept_pmtu(const struct sock * sk)318 static inline bool ip_sk_accept_pmtu(const struct sock *sk)
319 {
320 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
321 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
322 }
323
ip_sk_use_pmtu(const struct sock * sk)324 static inline bool ip_sk_use_pmtu(const struct sock *sk)
325 {
326 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
327 }
328
ip_sk_ignore_df(const struct sock * sk)329 static inline bool ip_sk_ignore_df(const struct sock *sk)
330 {
331 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
332 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
333 }
334
ip_dst_mtu_maybe_forward(const struct dst_entry * dst,bool forwarding)335 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
336 bool forwarding)
337 {
338 struct net *net = dev_net(dst->dev);
339
340 if (net->ipv4.sysctl_ip_fwd_use_pmtu ||
341 dst_metric_locked(dst, RTAX_MTU) ||
342 !forwarding)
343 return dst_mtu(dst);
344
345 return min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU);
346 }
347
ip_skb_dst_mtu(struct sock * sk,const struct sk_buff * skb)348 static inline unsigned int ip_skb_dst_mtu(struct sock *sk,
349 const struct sk_buff *skb)
350 {
351 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
352 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
353
354 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
355 }
356
357 return min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU);
358 }
359
360 u32 ip_idents_reserve(u32 hash, int segs);
361 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
362
ip_select_ident_segs(struct net * net,struct sk_buff * skb,struct sock * sk,int segs)363 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
364 struct sock *sk, int segs)
365 {
366 struct iphdr *iph = ip_hdr(skb);
367
368 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
369 /* This is only to work around buggy Windows95/2000
370 * VJ compression implementations. If the ID field
371 * does not change, they drop every other packet in
372 * a TCP stream using header compression.
373 */
374 if (sk && inet_sk(sk)->inet_daddr) {
375 iph->id = htons(inet_sk(sk)->inet_id);
376 inet_sk(sk)->inet_id += segs;
377 } else {
378 iph->id = 0;
379 }
380 } else {
381 __ip_select_ident(net, iph, segs);
382 }
383 }
384
ip_select_ident(struct net * net,struct sk_buff * skb,struct sock * sk)385 static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
386 struct sock *sk)
387 {
388 ip_select_ident_segs(net, skb, sk, 1);
389 }
390
inet_compute_pseudo(struct sk_buff * skb,int proto)391 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
392 {
393 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
394 skb->len, proto, 0);
395 }
396
397 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
398 * Equivalent to : flow->v4addrs.src = iph->saddr;
399 * flow->v4addrs.dst = iph->daddr;
400 */
iph_to_flow_copy_v4addrs(struct flow_keys * flow,const struct iphdr * iph)401 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
402 const struct iphdr *iph)
403 {
404 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
405 offsetof(typeof(flow->addrs), v4addrs.src) +
406 sizeof(flow->addrs.v4addrs.src));
407 memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs));
408 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
409 }
410
inet_gro_compute_pseudo(struct sk_buff * skb,int proto)411 static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto)
412 {
413 const struct iphdr *iph = skb_gro_network_header(skb);
414
415 return csum_tcpudp_nofold(iph->saddr, iph->daddr,
416 skb_gro_len(skb), proto, 0);
417 }
418
419 /*
420 * Map a multicast IP onto multicast MAC for type ethernet.
421 */
422
ip_eth_mc_map(__be32 naddr,char * buf)423 static inline void ip_eth_mc_map(__be32 naddr, char *buf)
424 {
425 __u32 addr=ntohl(naddr);
426 buf[0]=0x01;
427 buf[1]=0x00;
428 buf[2]=0x5e;
429 buf[5]=addr&0xFF;
430 addr>>=8;
431 buf[4]=addr&0xFF;
432 addr>>=8;
433 buf[3]=addr&0x7F;
434 }
435
436 /*
437 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
438 * Leave P_Key as 0 to be filled in by driver.
439 */
440
ip_ib_mc_map(__be32 naddr,const unsigned char * broadcast,char * buf)441 static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
442 {
443 __u32 addr;
444 unsigned char scope = broadcast[5] & 0xF;
445
446 buf[0] = 0; /* Reserved */
447 buf[1] = 0xff; /* Multicast QPN */
448 buf[2] = 0xff;
449 buf[3] = 0xff;
450 addr = ntohl(naddr);
451 buf[4] = 0xff;
452 buf[5] = 0x10 | scope; /* scope from broadcast address */
453 buf[6] = 0x40; /* IPv4 signature */
454 buf[7] = 0x1b;
455 buf[8] = broadcast[8]; /* P_Key */
456 buf[9] = broadcast[9];
457 buf[10] = 0;
458 buf[11] = 0;
459 buf[12] = 0;
460 buf[13] = 0;
461 buf[14] = 0;
462 buf[15] = 0;
463 buf[19] = addr & 0xff;
464 addr >>= 8;
465 buf[18] = addr & 0xff;
466 addr >>= 8;
467 buf[17] = addr & 0xff;
468 addr >>= 8;
469 buf[16] = addr & 0x0f;
470 }
471
ip_ipgre_mc_map(__be32 naddr,const unsigned char * broadcast,char * buf)472 static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
473 {
474 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0)
475 memcpy(buf, broadcast, 4);
476 else
477 memcpy(buf, &naddr, sizeof(naddr));
478 }
479
480 #if IS_ENABLED(CONFIG_IPV6)
481 #include <linux/ipv6.h>
482 #endif
483
inet_reset_saddr(struct sock * sk)484 static __inline__ void inet_reset_saddr(struct sock *sk)
485 {
486 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
487 #if IS_ENABLED(CONFIG_IPV6)
488 if (sk->sk_family == PF_INET6) {
489 struct ipv6_pinfo *np = inet6_sk(sk);
490
491 memset(&np->saddr, 0, sizeof(np->saddr));
492 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
493 }
494 #endif
495 }
496
497 #endif
498
ipv4_addr_hash(__be32 ip)499 static inline unsigned int ipv4_addr_hash(__be32 ip)
500 {
501 return (__force unsigned int) ip;
502 }
503
504 bool ip_call_ra_chain(struct sk_buff *skb);
505
506 /*
507 * Functions provided by ip_fragment.c
508 */
509
510 enum ip_defrag_users {
511 IP_DEFRAG_LOCAL_DELIVER,
512 IP_DEFRAG_CALL_RA_CHAIN,
513 IP_DEFRAG_CONNTRACK_IN,
514 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
515 IP_DEFRAG_CONNTRACK_OUT,
516 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
517 IP_DEFRAG_CONNTRACK_BRIDGE_IN,
518 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
519 IP_DEFRAG_VS_IN,
520 IP_DEFRAG_VS_OUT,
521 IP_DEFRAG_VS_FWD,
522 IP_DEFRAG_AF_PACKET,
523 IP_DEFRAG_MACVLAN,
524 };
525
526 /* Return true if the value of 'user' is between 'lower_bond'
527 * and 'upper_bond' inclusively.
528 */
ip_defrag_user_in_between(u32 user,enum ip_defrag_users lower_bond,enum ip_defrag_users upper_bond)529 static inline bool ip_defrag_user_in_between(u32 user,
530 enum ip_defrag_users lower_bond,
531 enum ip_defrag_users upper_bond)
532 {
533 return user >= lower_bond && user <= upper_bond;
534 }
535
536 int ip_defrag(struct net *net, struct sk_buff *skb, u32 user);
537 #ifdef CONFIG_INET
538 struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user);
539 #else
ip_check_defrag(struct net * net,struct sk_buff * skb,u32 user)540 static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
541 {
542 return skb;
543 }
544 #endif
545 int ip_frag_mem(struct net *net);
546
547 /*
548 * Functions provided by ip_forward.c
549 */
550
551 int ip_forward(struct sk_buff *skb);
552
553 /*
554 * Functions provided by ip_options.c
555 */
556
557 void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
558 __be32 daddr, struct rtable *rt, int is_frag);
559
560 int __ip_options_echo(struct ip_options *dopt, struct sk_buff *skb,
561 const struct ip_options *sopt);
ip_options_echo(struct ip_options * dopt,struct sk_buff * skb)562 static inline int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb)
563 {
564 return __ip_options_echo(dopt, skb, &IPCB(skb)->opt);
565 }
566
567 void ip_options_fragment(struct sk_buff *skb);
568 int ip_options_compile(struct net *net, struct ip_options *opt,
569 struct sk_buff *skb);
570 int ip_options_get(struct net *net, struct ip_options_rcu **optp,
571 unsigned char *data, int optlen);
572 int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp,
573 unsigned char __user *data, int optlen);
574 void ip_options_undo(struct ip_options *opt);
575 void ip_forward_options(struct sk_buff *skb);
576 int ip_options_rcv_srr(struct sk_buff *skb);
577
578 /*
579 * Functions provided by ip_sockglue.c
580 */
581
582 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
583 void ip_cmsg_recv_offset(struct msghdr *msg, struct sk_buff *skb, int tlen, int offset);
584 int ip_cmsg_send(struct sock *sk, struct msghdr *msg,
585 struct ipcm_cookie *ipc, bool allow_ipv6);
586 int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
587 unsigned int optlen);
588 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
589 int __user *optlen);
590 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
591 char __user *optval, unsigned int optlen);
592 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
593 char __user *optval, int __user *optlen);
594 int ip_ra_control(struct sock *sk, unsigned char on,
595 void (*destructor)(struct sock *));
596
597 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
598 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
599 u32 info, u8 *payload);
600 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
601 u32 info);
602
ip_cmsg_recv(struct msghdr * msg,struct sk_buff * skb)603 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
604 {
605 ip_cmsg_recv_offset(msg, skb, 0, 0);
606 }
607
608 bool icmp_global_allow(void);
609 extern int sysctl_icmp_msgs_per_sec;
610 extern int sysctl_icmp_msgs_burst;
611
612 #ifdef CONFIG_PROC_FS
613 int ip_misc_proc_init(void);
614 #endif
615
616 #endif /* _IP_H */
617