xref: /openbmc/linux/include/net/ip.h (revision 8c749ce9)
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 struct sock;
37 
38 struct inet_skb_parm {
39 	struct ip_options	opt;		/* Compiled IP options		*/
40 	unsigned char		flags;
41 
42 #define IPSKB_FORWARDED		BIT(0)
43 #define IPSKB_XFRM_TUNNEL_SIZE	BIT(1)
44 #define IPSKB_XFRM_TRANSFORMED	BIT(2)
45 #define IPSKB_FRAG_COMPLETE	BIT(3)
46 #define IPSKB_REROUTED		BIT(4)
47 #define IPSKB_DOREDIRECT	BIT(5)
48 #define IPSKB_FRAG_PMTU		BIT(6)
49 
50 	u16			frag_max_size;
51 };
52 
53 static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
54 {
55 	return ip_hdr(skb)->ihl * 4;
56 }
57 
58 struct ipcm_cookie {
59 	__be32			addr;
60 	int			oif;
61 	struct ip_options_rcu	*opt;
62 	__u8			tx_flags;
63 	__u8			ttl;
64 	__s16			tos;
65 	char			priority;
66 };
67 
68 #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
69 #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
70 
71 struct ip_ra_chain {
72 	struct ip_ra_chain __rcu *next;
73 	struct sock		*sk;
74 	union {
75 		void			(*destructor)(struct sock *);
76 		struct sock		*saved_sk;
77 	};
78 	struct rcu_head		rcu;
79 };
80 
81 extern struct ip_ra_chain __rcu *ip_ra_chain;
82 
83 /* IP flags. */
84 #define IP_CE		0x8000		/* Flag: "Congestion"		*/
85 #define IP_DF		0x4000		/* Flag: "Don't Fragment"	*/
86 #define IP_MF		0x2000		/* Flag: "More Fragments"	*/
87 #define IP_OFFSET	0x1FFF		/* "Fragment Offset" part	*/
88 
89 #define IP_FRAG_TIME	(30 * HZ)		/* fragment lifetime	*/
90 
91 struct msghdr;
92 struct net_device;
93 struct packet_type;
94 struct rtable;
95 struct sockaddr;
96 
97 int igmp_mc_init(void);
98 
99 /*
100  *	Functions provided by ip.c
101  */
102 
103 int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
104 			  __be32 saddr, __be32 daddr,
105 			  struct ip_options_rcu *opt);
106 int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
107 	   struct net_device *orig_dev);
108 int ip_local_deliver(struct sk_buff *skb);
109 int ip_mr_input(struct sk_buff *skb);
110 int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb);
111 int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb);
112 int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
113 		   int (*output)(struct net *, struct sock *, struct sk_buff *));
114 void ip_send_check(struct iphdr *ip);
115 int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
116 int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
117 
118 int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
119 void ip_init(void);
120 int ip_append_data(struct sock *sk, struct flowi4 *fl4,
121 		   int getfrag(void *from, char *to, int offset, int len,
122 			       int odd, struct sk_buff *skb),
123 		   void *from, int len, int protolen,
124 		   struct ipcm_cookie *ipc,
125 		   struct rtable **rt,
126 		   unsigned int flags);
127 int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
128 		       struct sk_buff *skb);
129 ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
130 		       int offset, size_t size, int flags);
131 struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
132 			      struct sk_buff_head *queue,
133 			      struct inet_cork *cork);
134 int ip_send_skb(struct net *net, struct sk_buff *skb);
135 int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
136 void ip_flush_pending_frames(struct sock *sk);
137 struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4,
138 			    int getfrag(void *from, char *to, int offset,
139 					int len, int odd, struct sk_buff *skb),
140 			    void *from, int length, int transhdrlen,
141 			    struct ipcm_cookie *ipc, struct rtable **rtp,
142 			    unsigned int flags);
143 
144 static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
145 {
146 	return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
147 }
148 
149 static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
150 {
151 	return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
152 }
153 
154 static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
155 {
156 	return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
157 }
158 
159 /* datagram.c */
160 int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
161 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
162 
163 void ip4_datagram_release_cb(struct sock *sk);
164 
165 struct ip_reply_arg {
166 	struct kvec iov[1];
167 	int	    flags;
168 	__wsum 	    csum;
169 	int	    csumoffset; /* u16 offset of csum in iov[0].iov_base */
170 				/* -1 if not needed */
171 	int	    bound_dev_if;
172 	u8  	    tos;
173 };
174 
175 #define IP_REPLY_ARG_NOSRCCHECK 1
176 
177 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
178 {
179 	return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
180 }
181 
182 void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
183 			   const struct ip_options *sopt,
184 			   __be32 daddr, __be32 saddr,
185 			   const struct ip_reply_arg *arg,
186 			   unsigned int len);
187 
188 #define IP_INC_STATS(net, field)	SNMP_INC_STATS64((net)->mib.ip_statistics, field)
189 #define IP_INC_STATS_BH(net, field)	SNMP_INC_STATS64_BH((net)->mib.ip_statistics, field)
190 #define IP_ADD_STATS(net, field, val)	SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
191 #define IP_ADD_STATS_BH(net, field, val) SNMP_ADD_STATS64_BH((net)->mib.ip_statistics, field, val)
192 #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
193 #define IP_UPD_PO_STATS_BH(net, field, val) SNMP_UPD_PO_STATS64_BH((net)->mib.ip_statistics, field, val)
194 #define NET_INC_STATS(net, field)	SNMP_INC_STATS((net)->mib.net_statistics, field)
195 #define NET_INC_STATS_BH(net, field)	SNMP_INC_STATS_BH((net)->mib.net_statistics, field)
196 #define NET_INC_STATS_USER(net, field) 	SNMP_INC_STATS_USER((net)->mib.net_statistics, field)
197 #define NET_ADD_STATS(net, field, adnd)	SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
198 #define NET_ADD_STATS_BH(net, field, adnd) SNMP_ADD_STATS_BH((net)->mib.net_statistics, field, adnd)
199 #define NET_ADD_STATS_USER(net, field, adnd) SNMP_ADD_STATS_USER((net)->mib.net_statistics, field, adnd)
200 
201 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct);
202 unsigned long snmp_fold_field(void __percpu *mib, int offt);
203 #if BITS_PER_LONG==32
204 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
205 			 size_t syncp_offset);
206 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
207 #else
208 static inline u64  snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
209 					size_t syncp_offset)
210 {
211 	return snmp_get_cpu_field(mib, cpu, offct);
212 
213 }
214 
215 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
216 {
217 	return snmp_fold_field(mib, offt);
218 }
219 #endif
220 
221 void inet_get_local_port_range(struct net *net, int *low, int *high);
222 
223 #ifdef CONFIG_SYSCTL
224 static inline int inet_is_local_reserved_port(struct net *net, int port)
225 {
226 	if (!net->ipv4.sysctl_local_reserved_ports)
227 		return 0;
228 	return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
229 }
230 
231 static inline bool sysctl_dev_name_is_allowed(const char *name)
232 {
233 	return strcmp(name, "default") != 0  && strcmp(name, "all") != 0;
234 }
235 
236 #else
237 static inline int inet_is_local_reserved_port(struct net *net, int port)
238 {
239 	return 0;
240 }
241 #endif
242 
243 /* From inetpeer.c */
244 extern int inet_peer_threshold;
245 extern int inet_peer_minttl;
246 extern int inet_peer_maxttl;
247 
248 /* From ip_input.c */
249 extern int sysctl_ip_early_demux;
250 
251 /* From ip_output.c */
252 extern int sysctl_ip_dynaddr;
253 
254 void ipfrag_init(void);
255 
256 void ip_static_sysctl_init(void);
257 
258 #define IP4_REPLY_MARK(net, mark) \
259 	((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0)
260 
261 static inline bool ip_is_fragment(const struct iphdr *iph)
262 {
263 	return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
264 }
265 
266 #ifdef CONFIG_INET
267 #include <net/dst.h>
268 
269 /* The function in 2.2 was invalid, producing wrong result for
270  * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
271 static inline
272 int ip_decrease_ttl(struct iphdr *iph)
273 {
274 	u32 check = (__force u32)iph->check;
275 	check += (__force u32)htons(0x0100);
276 	iph->check = (__force __sum16)(check + (check>=0xFFFF));
277 	return --iph->ttl;
278 }
279 
280 static inline
281 int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
282 {
283 	u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
284 
285 	return  pmtudisc == IP_PMTUDISC_DO ||
286 		(pmtudisc == IP_PMTUDISC_WANT &&
287 		 !(dst_metric_locked(dst, RTAX_MTU)));
288 }
289 
290 static inline bool ip_sk_accept_pmtu(const struct sock *sk)
291 {
292 	return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
293 	       inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
294 }
295 
296 static inline bool ip_sk_use_pmtu(const struct sock *sk)
297 {
298 	return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
299 }
300 
301 static inline bool ip_sk_ignore_df(const struct sock *sk)
302 {
303 	return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
304 	       inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
305 }
306 
307 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
308 						    bool forwarding)
309 {
310 	struct net *net = dev_net(dst->dev);
311 
312 	if (net->ipv4.sysctl_ip_fwd_use_pmtu ||
313 	    dst_metric_locked(dst, RTAX_MTU) ||
314 	    !forwarding)
315 		return dst_mtu(dst);
316 
317 	return min(dst->dev->mtu, IP_MAX_MTU);
318 }
319 
320 static inline unsigned int ip_skb_dst_mtu(const struct sk_buff *skb)
321 {
322 	struct sock *sk = skb->sk;
323 
324 	if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
325 		bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
326 
327 		return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
328 	}
329 
330 	return min(skb_dst(skb)->dev->mtu, IP_MAX_MTU);
331 }
332 
333 u32 ip_idents_reserve(u32 hash, int segs);
334 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
335 
336 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
337 					struct sock *sk, int segs)
338 {
339 	struct iphdr *iph = ip_hdr(skb);
340 
341 	if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
342 		/* This is only to work around buggy Windows95/2000
343 		 * VJ compression implementations.  If the ID field
344 		 * does not change, they drop every other packet in
345 		 * a TCP stream using header compression.
346 		 */
347 		if (sk && inet_sk(sk)->inet_daddr) {
348 			iph->id = htons(inet_sk(sk)->inet_id);
349 			inet_sk(sk)->inet_id += segs;
350 		} else {
351 			iph->id = 0;
352 		}
353 	} else {
354 		__ip_select_ident(net, iph, segs);
355 	}
356 }
357 
358 static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
359 				   struct sock *sk)
360 {
361 	ip_select_ident_segs(net, skb, sk, 1);
362 }
363 
364 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
365 {
366 	return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
367 				  skb->len, proto, 0);
368 }
369 
370 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
371  * Equivalent to :	flow->v4addrs.src = iph->saddr;
372  *			flow->v4addrs.dst = iph->daddr;
373  */
374 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
375 					    const struct iphdr *iph)
376 {
377 	BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
378 		     offsetof(typeof(flow->addrs), v4addrs.src) +
379 			      sizeof(flow->addrs.v4addrs.src));
380 	memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs));
381 	flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
382 }
383 
384 static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto)
385 {
386 	const struct iphdr *iph = skb_gro_network_header(skb);
387 
388 	return csum_tcpudp_nofold(iph->saddr, iph->daddr,
389 				  skb_gro_len(skb), proto, 0);
390 }
391 
392 /*
393  *	Map a multicast IP onto multicast MAC for type ethernet.
394  */
395 
396 static inline void ip_eth_mc_map(__be32 naddr, char *buf)
397 {
398 	__u32 addr=ntohl(naddr);
399 	buf[0]=0x01;
400 	buf[1]=0x00;
401 	buf[2]=0x5e;
402 	buf[5]=addr&0xFF;
403 	addr>>=8;
404 	buf[4]=addr&0xFF;
405 	addr>>=8;
406 	buf[3]=addr&0x7F;
407 }
408 
409 /*
410  *	Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
411  *	Leave P_Key as 0 to be filled in by driver.
412  */
413 
414 static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
415 {
416 	__u32 addr;
417 	unsigned char scope = broadcast[5] & 0xF;
418 
419 	buf[0]  = 0;		/* Reserved */
420 	buf[1]  = 0xff;		/* Multicast QPN */
421 	buf[2]  = 0xff;
422 	buf[3]  = 0xff;
423 	addr    = ntohl(naddr);
424 	buf[4]  = 0xff;
425 	buf[5]  = 0x10 | scope;	/* scope from broadcast address */
426 	buf[6]  = 0x40;		/* IPv4 signature */
427 	buf[7]  = 0x1b;
428 	buf[8]  = broadcast[8];		/* P_Key */
429 	buf[9]  = broadcast[9];
430 	buf[10] = 0;
431 	buf[11] = 0;
432 	buf[12] = 0;
433 	buf[13] = 0;
434 	buf[14] = 0;
435 	buf[15] = 0;
436 	buf[19] = addr & 0xff;
437 	addr  >>= 8;
438 	buf[18] = addr & 0xff;
439 	addr  >>= 8;
440 	buf[17] = addr & 0xff;
441 	addr  >>= 8;
442 	buf[16] = addr & 0x0f;
443 }
444 
445 static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
446 {
447 	if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0)
448 		memcpy(buf, broadcast, 4);
449 	else
450 		memcpy(buf, &naddr, sizeof(naddr));
451 }
452 
453 #if IS_ENABLED(CONFIG_IPV6)
454 #include <linux/ipv6.h>
455 #endif
456 
457 static __inline__ void inet_reset_saddr(struct sock *sk)
458 {
459 	inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
460 #if IS_ENABLED(CONFIG_IPV6)
461 	if (sk->sk_family == PF_INET6) {
462 		struct ipv6_pinfo *np = inet6_sk(sk);
463 
464 		memset(&np->saddr, 0, sizeof(np->saddr));
465 		memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
466 	}
467 #endif
468 }
469 
470 #endif
471 
472 static inline unsigned int ipv4_addr_hash(__be32 ip)
473 {
474 	return (__force unsigned int) ip;
475 }
476 
477 bool ip_call_ra_chain(struct sk_buff *skb);
478 
479 /*
480  *	Functions provided by ip_fragment.c
481  */
482 
483 enum ip_defrag_users {
484 	IP_DEFRAG_LOCAL_DELIVER,
485 	IP_DEFRAG_CALL_RA_CHAIN,
486 	IP_DEFRAG_CONNTRACK_IN,
487 	__IP_DEFRAG_CONNTRACK_IN_END	= IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
488 	IP_DEFRAG_CONNTRACK_OUT,
489 	__IP_DEFRAG_CONNTRACK_OUT_END	= IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
490 	IP_DEFRAG_CONNTRACK_BRIDGE_IN,
491 	__IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
492 	IP_DEFRAG_VS_IN,
493 	IP_DEFRAG_VS_OUT,
494 	IP_DEFRAG_VS_FWD,
495 	IP_DEFRAG_AF_PACKET,
496 	IP_DEFRAG_MACVLAN,
497 };
498 
499 /* Return true if the value of 'user' is between 'lower_bond'
500  * and 'upper_bond' inclusively.
501  */
502 static inline bool ip_defrag_user_in_between(u32 user,
503 					     enum ip_defrag_users lower_bond,
504 					     enum ip_defrag_users upper_bond)
505 {
506 	return user >= lower_bond && user <= upper_bond;
507 }
508 
509 int ip_defrag(struct net *net, struct sk_buff *skb, u32 user);
510 #ifdef CONFIG_INET
511 struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user);
512 #else
513 static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
514 {
515 	return skb;
516 }
517 #endif
518 int ip_frag_mem(struct net *net);
519 
520 /*
521  *	Functions provided by ip_forward.c
522  */
523 
524 int ip_forward(struct sk_buff *skb);
525 
526 /*
527  *	Functions provided by ip_options.c
528  */
529 
530 void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
531 		      __be32 daddr, struct rtable *rt, int is_frag);
532 
533 int __ip_options_echo(struct ip_options *dopt, struct sk_buff *skb,
534 		      const struct ip_options *sopt);
535 static inline int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb)
536 {
537 	return __ip_options_echo(dopt, skb, &IPCB(skb)->opt);
538 }
539 
540 void ip_options_fragment(struct sk_buff *skb);
541 int ip_options_compile(struct net *net, struct ip_options *opt,
542 		       struct sk_buff *skb);
543 int ip_options_get(struct net *net, struct ip_options_rcu **optp,
544 		   unsigned char *data, int optlen);
545 int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp,
546 			     unsigned char __user *data, int optlen);
547 void ip_options_undo(struct ip_options *opt);
548 void ip_forward_options(struct sk_buff *skb);
549 int ip_options_rcv_srr(struct sk_buff *skb);
550 
551 /*
552  *	Functions provided by ip_sockglue.c
553  */
554 
555 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
556 void ip_cmsg_recv_offset(struct msghdr *msg, struct sk_buff *skb, int offset);
557 int ip_cmsg_send(struct net *net, struct msghdr *msg,
558 		 struct ipcm_cookie *ipc, bool allow_ipv6);
559 int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
560 		  unsigned int optlen);
561 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
562 		  int __user *optlen);
563 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
564 			 char __user *optval, unsigned int optlen);
565 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
566 			 char __user *optval, int __user *optlen);
567 int ip_ra_control(struct sock *sk, unsigned char on,
568 		  void (*destructor)(struct sock *));
569 
570 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
571 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
572 		   u32 info, u8 *payload);
573 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
574 		    u32 info);
575 
576 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
577 {
578 	ip_cmsg_recv_offset(msg, skb, 0);
579 }
580 
581 bool icmp_global_allow(void);
582 extern int sysctl_icmp_msgs_per_sec;
583 extern int sysctl_icmp_msgs_burst;
584 
585 #ifdef CONFIG_PROC_FS
586 int ip_misc_proc_init(void);
587 #endif
588 
589 #endif	/* _IP_H */
590