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_MAX_PMTU 65535U /* RFC 2675, Section 5.1 */
37 #define IPV4_MIN_MTU 68 /* RFC 791 */
38
39 struct sock;
40
41 struct inet_skb_parm {
42 int iif;
43 struct ip_options opt; /* Compiled IP options */
44 u16 flags;
45
46 #define IPSKB_FORWARDED BIT(0)
47 #define IPSKB_XFRM_TUNNEL_SIZE BIT(1)
48 #define IPSKB_XFRM_TRANSFORMED BIT(2)
49 #define IPSKB_FRAG_COMPLETE BIT(3)
50 #define IPSKB_REROUTED BIT(4)
51 #define IPSKB_DOREDIRECT BIT(5)
52 #define IPSKB_FRAG_PMTU BIT(6)
53 #define IPSKB_L3SLAVE BIT(7)
54
55 u16 frag_max_size;
56 };
57
ipv4_l3mdev_skb(u16 flags)58 static inline bool ipv4_l3mdev_skb(u16 flags)
59 {
60 return !!(flags & IPSKB_L3SLAVE);
61 }
62
ip_hdrlen(const struct sk_buff * skb)63 static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
64 {
65 return ip_hdr(skb)->ihl * 4;
66 }
67
68 struct ipcm_cookie {
69 struct sockcm_cookie sockc;
70 __be32 addr;
71 int oif;
72 struct ip_options_rcu *opt;
73 __u8 tx_flags;
74 __u8 ttl;
75 __s16 tos;
76 char priority;
77 };
78
79 #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
80 #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
81
82 /* return enslaved device index if relevant */
inet_sdif(struct sk_buff * skb)83 static inline int inet_sdif(struct sk_buff *skb)
84 {
85 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
86 if (skb && ipv4_l3mdev_skb(IPCB(skb)->flags))
87 return IPCB(skb)->iif;
88 #endif
89 return 0;
90 }
91
92 struct ip_ra_chain {
93 struct ip_ra_chain __rcu *next;
94 struct sock *sk;
95 union {
96 void (*destructor)(struct sock *);
97 struct sock *saved_sk;
98 };
99 struct rcu_head rcu;
100 };
101
102 extern struct ip_ra_chain __rcu *ip_ra_chain;
103
104 /* IP flags. */
105 #define IP_CE 0x8000 /* Flag: "Congestion" */
106 #define IP_DF 0x4000 /* Flag: "Don't Fragment" */
107 #define IP_MF 0x2000 /* Flag: "More Fragments" */
108 #define IP_OFFSET 0x1FFF /* "Fragment Offset" part */
109
110 #define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */
111
112 struct msghdr;
113 struct net_device;
114 struct packet_type;
115 struct rtable;
116 struct sockaddr;
117
118 int igmp_mc_init(void);
119
120 /*
121 * Functions provided by ip.c
122 */
123
124 int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
125 __be32 saddr, __be32 daddr,
126 struct ip_options_rcu *opt);
127 int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
128 struct net_device *orig_dev);
129 int ip_local_deliver(struct sk_buff *skb);
130 int ip_mr_input(struct sk_buff *skb);
131 int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb);
132 int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb);
133 int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
134 int (*output)(struct net *, struct sock *, struct sk_buff *));
135 void ip_send_check(struct iphdr *ip);
136 int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
137 int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
138
139 int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
140 void ip_init(void);
141 int ip_append_data(struct sock *sk, struct flowi4 *fl4,
142 int getfrag(void *from, char *to, int offset, int len,
143 int odd, struct sk_buff *skb),
144 void *from, int len, int protolen,
145 struct ipcm_cookie *ipc,
146 struct rtable **rt,
147 unsigned int flags);
148 int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
149 struct sk_buff *skb);
150 ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
151 int offset, size_t size, int flags);
152 struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
153 struct sk_buff_head *queue,
154 struct inet_cork *cork);
155 int ip_send_skb(struct net *net, struct sk_buff *skb);
156 int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
157 void ip_flush_pending_frames(struct sock *sk);
158 struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4,
159 int getfrag(void *from, char *to, int offset,
160 int len, int odd, struct sk_buff *skb),
161 void *from, int length, int transhdrlen,
162 struct ipcm_cookie *ipc, struct rtable **rtp,
163 unsigned int flags);
164
ip_finish_skb(struct sock * sk,struct flowi4 * fl4)165 static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
166 {
167 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
168 }
169
get_rttos(struct ipcm_cookie * ipc,struct inet_sock * inet)170 static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
171 {
172 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
173 }
174
get_rtconn_flags(struct ipcm_cookie * ipc,struct sock * sk)175 static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
176 {
177 return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
178 }
179
180 /* datagram.c */
181 int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
182 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
183
184 void ip4_datagram_release_cb(struct sock *sk);
185
186 struct ip_reply_arg {
187 struct kvec iov[1];
188 int flags;
189 __wsum csum;
190 int csumoffset; /* u16 offset of csum in iov[0].iov_base */
191 /* -1 if not needed */
192 int bound_dev_if;
193 u8 tos;
194 kuid_t uid;
195 };
196
197 #define IP_REPLY_ARG_NOSRCCHECK 1
198
ip_reply_arg_flowi_flags(const struct ip_reply_arg * arg)199 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
200 {
201 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
202 }
203
204 void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
205 const struct ip_options *sopt,
206 __be32 daddr, __be32 saddr,
207 const struct ip_reply_arg *arg,
208 unsigned int len);
209
210 #define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field)
211 #define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field)
212 #define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
213 #define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
214 #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
215 #define __IP_UPD_PO_STATS(net, field, val) __SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
216 #define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field)
217 #define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field)
218 #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
219 #define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
220
221 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct);
222 unsigned long snmp_fold_field(void __percpu *mib, int offt);
223 #if BITS_PER_LONG==32
224 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
225 size_t syncp_offset);
226 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
227 #else
snmp_get_cpu_field64(void __percpu * mib,int cpu,int offct,size_t syncp_offset)228 static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
229 size_t syncp_offset)
230 {
231 return snmp_get_cpu_field(mib, cpu, offct);
232
233 }
234
snmp_fold_field64(void __percpu * mib,int offt,size_t syncp_off)235 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
236 {
237 return snmp_fold_field(mib, offt);
238 }
239 #endif
240
241 #define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \
242 { \
243 int i, c; \
244 for_each_possible_cpu(c) { \
245 for (i = 0; stats_list[i].name; i++) \
246 buff64[i] += snmp_get_cpu_field64( \
247 mib_statistic, \
248 c, stats_list[i].entry, \
249 offset); \
250 } \
251 }
252
253 #define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \
254 { \
255 int i, c; \
256 for_each_possible_cpu(c) { \
257 for (i = 0; stats_list[i].name; i++) \
258 buff[i] += snmp_get_cpu_field( \
259 mib_statistic, \
260 c, stats_list[i].entry); \
261 } \
262 }
263
264 void inet_get_local_port_range(struct net *net, int *low, int *high);
265
266 #ifdef CONFIG_SYSCTL
inet_is_local_reserved_port(struct net * net,int port)267 static inline int inet_is_local_reserved_port(struct net *net, int port)
268 {
269 if (!net->ipv4.sysctl_local_reserved_ports)
270 return 0;
271 return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
272 }
273
sysctl_dev_name_is_allowed(const char * name)274 static inline bool sysctl_dev_name_is_allowed(const char *name)
275 {
276 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0;
277 }
278
inet_prot_sock(struct net * net)279 static inline int inet_prot_sock(struct net *net)
280 {
281 return net->ipv4.sysctl_ip_prot_sock;
282 }
283
284 #else
inet_is_local_reserved_port(struct net * net,int port)285 static inline int inet_is_local_reserved_port(struct net *net, int port)
286 {
287 return 0;
288 }
289
inet_prot_sock(struct net * net)290 static inline int inet_prot_sock(struct net *net)
291 {
292 return PROT_SOCK;
293 }
294 #endif
295
296 __be32 inet_current_timestamp(void);
297
298 /* From inetpeer.c */
299 extern int inet_peer_threshold;
300 extern int inet_peer_minttl;
301 extern int inet_peer_maxttl;
302
303 void ipfrag_init(void);
304
305 void ip_static_sysctl_init(void);
306
307 #define IP4_REPLY_MARK(net, mark) \
308 ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0)
309
ip_is_fragment(const struct iphdr * iph)310 static inline bool ip_is_fragment(const struct iphdr *iph)
311 {
312 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
313 }
314
315 #ifdef CONFIG_INET
316 #include <net/dst.h>
317
318 /* The function in 2.2 was invalid, producing wrong result for
319 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
320 static inline
ip_decrease_ttl(struct iphdr * iph)321 int ip_decrease_ttl(struct iphdr *iph)
322 {
323 u32 check = (__force u32)iph->check;
324 check += (__force u32)htons(0x0100);
325 iph->check = (__force __sum16)(check + (check>=0xFFFF));
326 return --iph->ttl;
327 }
328
ip_mtu_locked(const struct dst_entry * dst)329 static inline int ip_mtu_locked(const struct dst_entry *dst)
330 {
331 const struct rtable *rt = (const struct rtable *)dst;
332
333 return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU);
334 }
335
336 static inline
ip_dont_fragment(const struct sock * sk,const struct dst_entry * dst)337 int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
338 {
339 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
340
341 return pmtudisc == IP_PMTUDISC_DO ||
342 (pmtudisc == IP_PMTUDISC_WANT &&
343 !ip_mtu_locked(dst));
344 }
345
ip_sk_accept_pmtu(const struct sock * sk)346 static inline bool ip_sk_accept_pmtu(const struct sock *sk)
347 {
348 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
349 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
350 }
351
ip_sk_use_pmtu(const struct sock * sk)352 static inline bool ip_sk_use_pmtu(const struct sock *sk)
353 {
354 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
355 }
356
ip_sk_ignore_df(const struct sock * sk)357 static inline bool ip_sk_ignore_df(const struct sock *sk)
358 {
359 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
360 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
361 }
362
ip_dst_mtu_maybe_forward(const struct dst_entry * dst,bool forwarding)363 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
364 bool forwarding)
365 {
366 struct net *net = dev_net(dst->dev);
367
368 if (net->ipv4.sysctl_ip_fwd_use_pmtu ||
369 ip_mtu_locked(dst) ||
370 !forwarding)
371 return dst_mtu(dst);
372
373 return min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU);
374 }
375
ip_skb_dst_mtu(struct sock * sk,const struct sk_buff * skb)376 static inline unsigned int ip_skb_dst_mtu(struct sock *sk,
377 const struct sk_buff *skb)
378 {
379 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
380 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
381
382 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
383 }
384
385 return min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU);
386 }
387
388 u32 ip_idents_reserve(u32 hash, int segs);
389 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
390
ip_select_ident_segs(struct net * net,struct sk_buff * skb,struct sock * sk,int segs)391 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
392 struct sock *sk, int segs)
393 {
394 struct iphdr *iph = ip_hdr(skb);
395
396 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
397 /* This is only to work around buggy Windows95/2000
398 * VJ compression implementations. If the ID field
399 * does not change, they drop every other packet in
400 * a TCP stream using header compression.
401 */
402 if (sk && inet_sk(sk)->inet_daddr) {
403 iph->id = htons(inet_sk(sk)->inet_id);
404 inet_sk(sk)->inet_id += segs;
405 } else {
406 iph->id = 0;
407 }
408 } else {
409 __ip_select_ident(net, iph, segs);
410 }
411 }
412
ip_select_ident(struct net * net,struct sk_buff * skb,struct sock * sk)413 static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
414 struct sock *sk)
415 {
416 ip_select_ident_segs(net, skb, sk, 1);
417 }
418
inet_compute_pseudo(struct sk_buff * skb,int proto)419 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
420 {
421 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
422 skb->len, proto, 0);
423 }
424
425 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
426 * Equivalent to : flow->v4addrs.src = iph->saddr;
427 * flow->v4addrs.dst = iph->daddr;
428 */
iph_to_flow_copy_v4addrs(struct flow_keys * flow,const struct iphdr * iph)429 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
430 const struct iphdr *iph)
431 {
432 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
433 offsetof(typeof(flow->addrs), v4addrs.src) +
434 sizeof(flow->addrs.v4addrs.src));
435 memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs));
436 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
437 }
438
inet_gro_compute_pseudo(struct sk_buff * skb,int proto)439 static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto)
440 {
441 const struct iphdr *iph = skb_gro_network_header(skb);
442
443 return csum_tcpudp_nofold(iph->saddr, iph->daddr,
444 skb_gro_len(skb), proto, 0);
445 }
446
447 /*
448 * Map a multicast IP onto multicast MAC for type ethernet.
449 */
450
ip_eth_mc_map(__be32 naddr,char * buf)451 static inline void ip_eth_mc_map(__be32 naddr, char *buf)
452 {
453 __u32 addr=ntohl(naddr);
454 buf[0]=0x01;
455 buf[1]=0x00;
456 buf[2]=0x5e;
457 buf[5]=addr&0xFF;
458 addr>>=8;
459 buf[4]=addr&0xFF;
460 addr>>=8;
461 buf[3]=addr&0x7F;
462 }
463
464 /*
465 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
466 * Leave P_Key as 0 to be filled in by driver.
467 */
468
ip_ib_mc_map(__be32 naddr,const unsigned char * broadcast,char * buf)469 static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
470 {
471 __u32 addr;
472 unsigned char scope = broadcast[5] & 0xF;
473
474 buf[0] = 0; /* Reserved */
475 buf[1] = 0xff; /* Multicast QPN */
476 buf[2] = 0xff;
477 buf[3] = 0xff;
478 addr = ntohl(naddr);
479 buf[4] = 0xff;
480 buf[5] = 0x10 | scope; /* scope from broadcast address */
481 buf[6] = 0x40; /* IPv4 signature */
482 buf[7] = 0x1b;
483 buf[8] = broadcast[8]; /* P_Key */
484 buf[9] = broadcast[9];
485 buf[10] = 0;
486 buf[11] = 0;
487 buf[12] = 0;
488 buf[13] = 0;
489 buf[14] = 0;
490 buf[15] = 0;
491 buf[19] = addr & 0xff;
492 addr >>= 8;
493 buf[18] = addr & 0xff;
494 addr >>= 8;
495 buf[17] = addr & 0xff;
496 addr >>= 8;
497 buf[16] = addr & 0x0f;
498 }
499
ip_ipgre_mc_map(__be32 naddr,const unsigned char * broadcast,char * buf)500 static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
501 {
502 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0)
503 memcpy(buf, broadcast, 4);
504 else
505 memcpy(buf, &naddr, sizeof(naddr));
506 }
507
508 #if IS_ENABLED(CONFIG_IPV6)
509 #include <linux/ipv6.h>
510 #endif
511
inet_reset_saddr(struct sock * sk)512 static __inline__ void inet_reset_saddr(struct sock *sk)
513 {
514 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
515 #if IS_ENABLED(CONFIG_IPV6)
516 if (sk->sk_family == PF_INET6) {
517 struct ipv6_pinfo *np = inet6_sk(sk);
518
519 memset(&np->saddr, 0, sizeof(np->saddr));
520 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
521 }
522 #endif
523 }
524
525 #endif
526
ipv4_addr_hash(__be32 ip)527 static inline unsigned int ipv4_addr_hash(__be32 ip)
528 {
529 return (__force unsigned int) ip;
530 }
531
532 bool ip_call_ra_chain(struct sk_buff *skb);
533
534 /*
535 * Functions provided by ip_fragment.c
536 */
537
538 enum ip_defrag_users {
539 IP_DEFRAG_LOCAL_DELIVER,
540 IP_DEFRAG_CALL_RA_CHAIN,
541 IP_DEFRAG_CONNTRACK_IN,
542 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
543 IP_DEFRAG_CONNTRACK_OUT,
544 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
545 IP_DEFRAG_CONNTRACK_BRIDGE_IN,
546 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
547 IP_DEFRAG_VS_IN,
548 IP_DEFRAG_VS_OUT,
549 IP_DEFRAG_VS_FWD,
550 IP_DEFRAG_AF_PACKET,
551 IP_DEFRAG_MACVLAN,
552 };
553
554 /* Return true if the value of 'user' is between 'lower_bond'
555 * and 'upper_bond' inclusively.
556 */
ip_defrag_user_in_between(u32 user,enum ip_defrag_users lower_bond,enum ip_defrag_users upper_bond)557 static inline bool ip_defrag_user_in_between(u32 user,
558 enum ip_defrag_users lower_bond,
559 enum ip_defrag_users upper_bond)
560 {
561 return user >= lower_bond && user <= upper_bond;
562 }
563
564 int ip_defrag(struct net *net, struct sk_buff *skb, u32 user);
565 #ifdef CONFIG_INET
566 struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user);
567 #else
ip_check_defrag(struct net * net,struct sk_buff * skb,u32 user)568 static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
569 {
570 return skb;
571 }
572 #endif
573
574 /*
575 * Functions provided by ip_forward.c
576 */
577
578 int ip_forward(struct sk_buff *skb);
579
580 /*
581 * Functions provided by ip_options.c
582 */
583
584 void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
585 __be32 daddr, struct rtable *rt, int is_frag);
586
587 int __ip_options_echo(struct net *net, struct ip_options *dopt,
588 struct sk_buff *skb, const struct ip_options *sopt);
ip_options_echo(struct net * net,struct ip_options * dopt,struct sk_buff * skb)589 static inline int ip_options_echo(struct net *net, struct ip_options *dopt,
590 struct sk_buff *skb)
591 {
592 return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt);
593 }
594
595 void ip_options_fragment(struct sk_buff *skb);
596 int __ip_options_compile(struct net *net, struct ip_options *opt,
597 struct sk_buff *skb, __be32 *info);
598 int ip_options_compile(struct net *net, struct ip_options *opt,
599 struct sk_buff *skb);
600 int ip_options_get(struct net *net, struct ip_options_rcu **optp,
601 unsigned char *data, int optlen);
602 int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp,
603 unsigned char __user *data, int optlen);
604 void ip_options_undo(struct ip_options *opt);
605 void ip_forward_options(struct sk_buff *skb);
606 int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev);
607
608 /*
609 * Functions provided by ip_sockglue.c
610 */
611
612 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
613 void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
614 struct sk_buff *skb, int tlen, int offset);
615 int ip_cmsg_send(struct sock *sk, struct msghdr *msg,
616 struct ipcm_cookie *ipc, bool allow_ipv6);
617 int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
618 unsigned int optlen);
619 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
620 int __user *optlen);
621 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
622 char __user *optval, unsigned int optlen);
623 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
624 char __user *optval, int __user *optlen);
625 int ip_ra_control(struct sock *sk, unsigned char on,
626 void (*destructor)(struct sock *));
627
628 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
629 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
630 u32 info, u8 *payload);
631 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
632 u32 info);
633
ip_cmsg_recv(struct msghdr * msg,struct sk_buff * skb)634 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
635 {
636 ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0);
637 }
638
639 bool icmp_global_allow(void);
640 extern int sysctl_icmp_msgs_per_sec;
641 extern int sysctl_icmp_msgs_burst;
642
643 #ifdef CONFIG_PROC_FS
644 int ip_misc_proc_init(void);
645 #endif
646
inetdev_valid_mtu(unsigned int mtu)647 static inline bool inetdev_valid_mtu(unsigned int mtu)
648 {
649 return likely(mtu >= IPV4_MIN_MTU);
650 }
651
652 #endif /* _IP_H */
653