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 #include <linux/jhash.h> 30 31 #include <net/inet_sock.h> 32 #include <net/route.h> 33 #include <net/snmp.h> 34 #include <net/flow.h> 35 #include <net/flow_dissector.h> 36 #include <net/netns/hash.h> 37 38 #define IPV4_MAX_PMTU 65535U /* RFC 2675, Section 5.1 */ 39 #define IPV4_MIN_MTU 68 /* RFC 791 */ 40 41 struct sock; 42 43 struct inet_skb_parm { 44 int iif; 45 struct ip_options opt; /* Compiled IP options */ 46 u16 flags; 47 48 #define IPSKB_FORWARDED BIT(0) 49 #define IPSKB_XFRM_TUNNEL_SIZE BIT(1) 50 #define IPSKB_XFRM_TRANSFORMED BIT(2) 51 #define IPSKB_FRAG_COMPLETE BIT(3) 52 #define IPSKB_REROUTED BIT(4) 53 #define IPSKB_DOREDIRECT BIT(5) 54 #define IPSKB_FRAG_PMTU BIT(6) 55 #define IPSKB_L3SLAVE BIT(7) 56 57 u16 frag_max_size; 58 }; 59 60 static inline bool ipv4_l3mdev_skb(u16 flags) 61 { 62 return !!(flags & IPSKB_L3SLAVE); 63 } 64 65 static inline unsigned int ip_hdrlen(const struct sk_buff *skb) 66 { 67 return ip_hdr(skb)->ihl * 4; 68 } 69 70 struct ipcm_cookie { 71 struct sockcm_cookie sockc; 72 __be32 addr; 73 int oif; 74 struct ip_options_rcu *opt; 75 __u8 ttl; 76 __s16 tos; 77 char priority; 78 __u16 gso_size; 79 }; 80 81 static inline void ipcm_init(struct ipcm_cookie *ipcm) 82 { 83 *ipcm = (struct ipcm_cookie) { .tos = -1 }; 84 } 85 86 static inline void ipcm_init_sk(struct ipcm_cookie *ipcm, 87 const struct inet_sock *inet) 88 { 89 ipcm_init(ipcm); 90 91 ipcm->sockc.tsflags = inet->sk.sk_tsflags; 92 ipcm->oif = inet->sk.sk_bound_dev_if; 93 ipcm->addr = inet->inet_saddr; 94 } 95 96 #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb)) 97 #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb)) 98 99 /* return enslaved device index if relevant */ 100 static inline int inet_sdif(struct sk_buff *skb) 101 { 102 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV) 103 if (skb && ipv4_l3mdev_skb(IPCB(skb)->flags)) 104 return IPCB(skb)->iif; 105 #endif 106 return 0; 107 } 108 109 /* Special input handler for packets caught by router alert option. 110 They are selected only by protocol field, and then processed likely 111 local ones; but only if someone wants them! Otherwise, router 112 not running rsvpd will kill RSVP. 113 114 It is user level problem, what it will make with them. 115 I have no idea, how it will masquearde or NAT them (it is joke, joke :-)), 116 but receiver should be enough clever f.e. to forward mtrace requests, 117 sent to multicast group to reach destination designated router. 118 */ 119 120 struct ip_ra_chain { 121 struct ip_ra_chain __rcu *next; 122 struct sock *sk; 123 union { 124 void (*destructor)(struct sock *); 125 struct sock *saved_sk; 126 }; 127 struct rcu_head rcu; 128 }; 129 130 /* IP flags. */ 131 #define IP_CE 0x8000 /* Flag: "Congestion" */ 132 #define IP_DF 0x4000 /* Flag: "Don't Fragment" */ 133 #define IP_MF 0x2000 /* Flag: "More Fragments" */ 134 #define IP_OFFSET 0x1FFF /* "Fragment Offset" part */ 135 136 #define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */ 137 138 struct msghdr; 139 struct net_device; 140 struct packet_type; 141 struct rtable; 142 struct sockaddr; 143 144 int igmp_mc_init(void); 145 146 /* 147 * Functions provided by ip.c 148 */ 149 150 int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk, 151 __be32 saddr, __be32 daddr, 152 struct ip_options_rcu *opt); 153 int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, 154 struct net_device *orig_dev); 155 void ip_list_rcv(struct list_head *head, struct packet_type *pt, 156 struct net_device *orig_dev); 157 int ip_local_deliver(struct sk_buff *skb); 158 int ip_mr_input(struct sk_buff *skb); 159 int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb); 160 int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb); 161 int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, 162 int (*output)(struct net *, struct sock *, struct sk_buff *)); 163 void ip_send_check(struct iphdr *ip); 164 int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 165 int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 166 167 int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, 168 __u8 tos); 169 void ip_init(void); 170 int ip_append_data(struct sock *sk, struct flowi4 *fl4, 171 int getfrag(void *from, char *to, int offset, int len, 172 int odd, struct sk_buff *skb), 173 void *from, int len, int protolen, 174 struct ipcm_cookie *ipc, 175 struct rtable **rt, 176 unsigned int flags); 177 int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, 178 struct sk_buff *skb); 179 ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page, 180 int offset, size_t size, int flags); 181 struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4, 182 struct sk_buff_head *queue, 183 struct inet_cork *cork); 184 int ip_send_skb(struct net *net, struct sk_buff *skb); 185 int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4); 186 void ip_flush_pending_frames(struct sock *sk); 187 struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4, 188 int getfrag(void *from, char *to, int offset, 189 int len, int odd, struct sk_buff *skb), 190 void *from, int length, int transhdrlen, 191 struct ipcm_cookie *ipc, struct rtable **rtp, 192 struct inet_cork *cork, unsigned int flags); 193 194 static inline int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, 195 struct flowi *fl) 196 { 197 return __ip_queue_xmit(sk, skb, fl, inet_sk(sk)->tos); 198 } 199 200 static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4) 201 { 202 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base); 203 } 204 205 static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet) 206 { 207 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos); 208 } 209 210 static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk) 211 { 212 return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk); 213 } 214 215 /* datagram.c */ 216 int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); 217 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); 218 219 void ip4_datagram_release_cb(struct sock *sk); 220 221 struct ip_reply_arg { 222 struct kvec iov[1]; 223 int flags; 224 __wsum csum; 225 int csumoffset; /* u16 offset of csum in iov[0].iov_base */ 226 /* -1 if not needed */ 227 int bound_dev_if; 228 u8 tos; 229 kuid_t uid; 230 }; 231 232 #define IP_REPLY_ARG_NOSRCCHECK 1 233 234 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg) 235 { 236 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0; 237 } 238 239 void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb, 240 const struct ip_options *sopt, 241 __be32 daddr, __be32 saddr, 242 const struct ip_reply_arg *arg, 243 unsigned int len); 244 245 #define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field) 246 #define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field) 247 #define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val) 248 #define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val) 249 #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val) 250 #define __IP_UPD_PO_STATS(net, field, val) __SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val) 251 #define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field) 252 #define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field) 253 #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd) 254 #define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd) 255 256 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct); 257 unsigned long snmp_fold_field(void __percpu *mib, int offt); 258 #if BITS_PER_LONG==32 259 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct, 260 size_t syncp_offset); 261 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off); 262 #else 263 static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct, 264 size_t syncp_offset) 265 { 266 return snmp_get_cpu_field(mib, cpu, offct); 267 268 } 269 270 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off) 271 { 272 return snmp_fold_field(mib, offt); 273 } 274 #endif 275 276 #define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \ 277 { \ 278 int i, c; \ 279 for_each_possible_cpu(c) { \ 280 for (i = 0; stats_list[i].name; i++) \ 281 buff64[i] += snmp_get_cpu_field64( \ 282 mib_statistic, \ 283 c, stats_list[i].entry, \ 284 offset); \ 285 } \ 286 } 287 288 #define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \ 289 { \ 290 int i, c; \ 291 for_each_possible_cpu(c) { \ 292 for (i = 0; stats_list[i].name; i++) \ 293 buff[i] += snmp_get_cpu_field( \ 294 mib_statistic, \ 295 c, stats_list[i].entry); \ 296 } \ 297 } 298 299 void inet_get_local_port_range(struct net *net, int *low, int *high); 300 301 #ifdef CONFIG_SYSCTL 302 static inline int inet_is_local_reserved_port(struct net *net, int port) 303 { 304 if (!net->ipv4.sysctl_local_reserved_ports) 305 return 0; 306 return test_bit(port, net->ipv4.sysctl_local_reserved_ports); 307 } 308 309 static inline bool sysctl_dev_name_is_allowed(const char *name) 310 { 311 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0; 312 } 313 314 static inline int inet_prot_sock(struct net *net) 315 { 316 return net->ipv4.sysctl_ip_prot_sock; 317 } 318 319 #else 320 static inline int inet_is_local_reserved_port(struct net *net, int port) 321 { 322 return 0; 323 } 324 325 static inline int inet_prot_sock(struct net *net) 326 { 327 return PROT_SOCK; 328 } 329 #endif 330 331 __be32 inet_current_timestamp(void); 332 333 /* From inetpeer.c */ 334 extern int inet_peer_threshold; 335 extern int inet_peer_minttl; 336 extern int inet_peer_maxttl; 337 338 void ipfrag_init(void); 339 340 void ip_static_sysctl_init(void); 341 342 #define IP4_REPLY_MARK(net, mark) \ 343 ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0) 344 345 static inline bool ip_is_fragment(const struct iphdr *iph) 346 { 347 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0; 348 } 349 350 #ifdef CONFIG_INET 351 #include <net/dst.h> 352 353 /* The function in 2.2 was invalid, producing wrong result for 354 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */ 355 static inline 356 int ip_decrease_ttl(struct iphdr *iph) 357 { 358 u32 check = (__force u32)iph->check; 359 check += (__force u32)htons(0x0100); 360 iph->check = (__force __sum16)(check + (check>=0xFFFF)); 361 return --iph->ttl; 362 } 363 364 static inline int ip_mtu_locked(const struct dst_entry *dst) 365 { 366 const struct rtable *rt = (const struct rtable *)dst; 367 368 return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU); 369 } 370 371 static inline 372 int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst) 373 { 374 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc); 375 376 return pmtudisc == IP_PMTUDISC_DO || 377 (pmtudisc == IP_PMTUDISC_WANT && 378 !ip_mtu_locked(dst)); 379 } 380 381 static inline bool ip_sk_accept_pmtu(const struct sock *sk) 382 { 383 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE && 384 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT; 385 } 386 387 static inline bool ip_sk_use_pmtu(const struct sock *sk) 388 { 389 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE; 390 } 391 392 static inline bool ip_sk_ignore_df(const struct sock *sk) 393 { 394 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO || 395 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT; 396 } 397 398 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, 399 bool forwarding) 400 { 401 struct net *net = dev_net(dst->dev); 402 403 if (net->ipv4.sysctl_ip_fwd_use_pmtu || 404 ip_mtu_locked(dst) || 405 !forwarding) 406 return dst_mtu(dst); 407 408 return min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU); 409 } 410 411 static inline unsigned int ip_skb_dst_mtu(struct sock *sk, 412 const struct sk_buff *skb) 413 { 414 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) { 415 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED; 416 417 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding); 418 } 419 420 return min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU); 421 } 422 423 struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx, 424 int fc_mx_len); 425 static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics) 426 { 427 if (fib_metrics != &dst_default_metrics && 428 refcount_dec_and_test(&fib_metrics->refcnt)) 429 kfree(fib_metrics); 430 } 431 432 /* ipv4 and ipv6 both use refcounted metrics if it is not the default */ 433 static inline 434 void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics) 435 { 436 dst_init_metrics(dst, fib_metrics->metrics, true); 437 438 if (fib_metrics != &dst_default_metrics) { 439 dst->_metrics |= DST_METRICS_REFCOUNTED; 440 refcount_inc(&fib_metrics->refcnt); 441 } 442 } 443 444 static inline 445 void ip_dst_metrics_put(struct dst_entry *dst) 446 { 447 struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst); 448 449 if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt)) 450 kfree(p); 451 } 452 453 u32 ip_idents_reserve(u32 hash, int segs); 454 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs); 455 456 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb, 457 struct sock *sk, int segs) 458 { 459 struct iphdr *iph = ip_hdr(skb); 460 461 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) { 462 /* This is only to work around buggy Windows95/2000 463 * VJ compression implementations. If the ID field 464 * does not change, they drop every other packet in 465 * a TCP stream using header compression. 466 */ 467 if (sk && inet_sk(sk)->inet_daddr) { 468 iph->id = htons(inet_sk(sk)->inet_id); 469 inet_sk(sk)->inet_id += segs; 470 } else { 471 iph->id = 0; 472 } 473 } else { 474 __ip_select_ident(net, iph, segs); 475 } 476 } 477 478 static inline void ip_select_ident(struct net *net, struct sk_buff *skb, 479 struct sock *sk) 480 { 481 ip_select_ident_segs(net, skb, sk, 1); 482 } 483 484 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto) 485 { 486 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, 487 skb->len, proto, 0); 488 } 489 490 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store 491 * Equivalent to : flow->v4addrs.src = iph->saddr; 492 * flow->v4addrs.dst = iph->daddr; 493 */ 494 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow, 495 const struct iphdr *iph) 496 { 497 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) != 498 offsetof(typeof(flow->addrs), v4addrs.src) + 499 sizeof(flow->addrs.v4addrs.src)); 500 memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs)); 501 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; 502 } 503 504 static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto) 505 { 506 const struct iphdr *iph = skb_gro_network_header(skb); 507 508 return csum_tcpudp_nofold(iph->saddr, iph->daddr, 509 skb_gro_len(skb), proto, 0); 510 } 511 512 /* 513 * Map a multicast IP onto multicast MAC for type ethernet. 514 */ 515 516 static inline void ip_eth_mc_map(__be32 naddr, char *buf) 517 { 518 __u32 addr=ntohl(naddr); 519 buf[0]=0x01; 520 buf[1]=0x00; 521 buf[2]=0x5e; 522 buf[5]=addr&0xFF; 523 addr>>=8; 524 buf[4]=addr&0xFF; 525 addr>>=8; 526 buf[3]=addr&0x7F; 527 } 528 529 /* 530 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand. 531 * Leave P_Key as 0 to be filled in by driver. 532 */ 533 534 static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) 535 { 536 __u32 addr; 537 unsigned char scope = broadcast[5] & 0xF; 538 539 buf[0] = 0; /* Reserved */ 540 buf[1] = 0xff; /* Multicast QPN */ 541 buf[2] = 0xff; 542 buf[3] = 0xff; 543 addr = ntohl(naddr); 544 buf[4] = 0xff; 545 buf[5] = 0x10 | scope; /* scope from broadcast address */ 546 buf[6] = 0x40; /* IPv4 signature */ 547 buf[7] = 0x1b; 548 buf[8] = broadcast[8]; /* P_Key */ 549 buf[9] = broadcast[9]; 550 buf[10] = 0; 551 buf[11] = 0; 552 buf[12] = 0; 553 buf[13] = 0; 554 buf[14] = 0; 555 buf[15] = 0; 556 buf[19] = addr & 0xff; 557 addr >>= 8; 558 buf[18] = addr & 0xff; 559 addr >>= 8; 560 buf[17] = addr & 0xff; 561 addr >>= 8; 562 buf[16] = addr & 0x0f; 563 } 564 565 static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) 566 { 567 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0) 568 memcpy(buf, broadcast, 4); 569 else 570 memcpy(buf, &naddr, sizeof(naddr)); 571 } 572 573 #if IS_ENABLED(CONFIG_IPV6) 574 #include <linux/ipv6.h> 575 #endif 576 577 static __inline__ void inet_reset_saddr(struct sock *sk) 578 { 579 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0; 580 #if IS_ENABLED(CONFIG_IPV6) 581 if (sk->sk_family == PF_INET6) { 582 struct ipv6_pinfo *np = inet6_sk(sk); 583 584 memset(&np->saddr, 0, sizeof(np->saddr)); 585 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr)); 586 } 587 #endif 588 } 589 590 #endif 591 592 static inline unsigned int ipv4_addr_hash(__be32 ip) 593 { 594 return (__force unsigned int) ip; 595 } 596 597 static inline u32 ipv4_portaddr_hash(const struct net *net, 598 __be32 saddr, 599 unsigned int port) 600 { 601 return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port; 602 } 603 604 bool ip_call_ra_chain(struct sk_buff *skb); 605 606 /* 607 * Functions provided by ip_fragment.c 608 */ 609 610 enum ip_defrag_users { 611 IP_DEFRAG_LOCAL_DELIVER, 612 IP_DEFRAG_CALL_RA_CHAIN, 613 IP_DEFRAG_CONNTRACK_IN, 614 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX, 615 IP_DEFRAG_CONNTRACK_OUT, 616 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX, 617 IP_DEFRAG_CONNTRACK_BRIDGE_IN, 618 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX, 619 IP_DEFRAG_VS_IN, 620 IP_DEFRAG_VS_OUT, 621 IP_DEFRAG_VS_FWD, 622 IP_DEFRAG_AF_PACKET, 623 IP_DEFRAG_MACVLAN, 624 }; 625 626 /* Return true if the value of 'user' is between 'lower_bond' 627 * and 'upper_bond' inclusively. 628 */ 629 static inline bool ip_defrag_user_in_between(u32 user, 630 enum ip_defrag_users lower_bond, 631 enum ip_defrag_users upper_bond) 632 { 633 return user >= lower_bond && user <= upper_bond; 634 } 635 636 int ip_defrag(struct net *net, struct sk_buff *skb, u32 user); 637 #ifdef CONFIG_INET 638 struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user); 639 #else 640 static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user) 641 { 642 return skb; 643 } 644 #endif 645 646 /* 647 * Functions provided by ip_forward.c 648 */ 649 650 int ip_forward(struct sk_buff *skb); 651 652 /* 653 * Functions provided by ip_options.c 654 */ 655 656 void ip_options_build(struct sk_buff *skb, struct ip_options *opt, 657 __be32 daddr, struct rtable *rt, int is_frag); 658 659 int __ip_options_echo(struct net *net, struct ip_options *dopt, 660 struct sk_buff *skb, const struct ip_options *sopt); 661 static inline int ip_options_echo(struct net *net, struct ip_options *dopt, 662 struct sk_buff *skb) 663 { 664 return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt); 665 } 666 667 void ip_options_fragment(struct sk_buff *skb); 668 int ip_options_compile(struct net *net, struct ip_options *opt, 669 struct sk_buff *skb); 670 int ip_options_get(struct net *net, struct ip_options_rcu **optp, 671 unsigned char *data, int optlen); 672 int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp, 673 unsigned char __user *data, int optlen); 674 void ip_options_undo(struct ip_options *opt); 675 void ip_forward_options(struct sk_buff *skb); 676 int ip_options_rcv_srr(struct sk_buff *skb); 677 678 /* 679 * Functions provided by ip_sockglue.c 680 */ 681 682 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb); 683 void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk, 684 struct sk_buff *skb, int tlen, int offset); 685 int ip_cmsg_send(struct sock *sk, struct msghdr *msg, 686 struct ipcm_cookie *ipc, bool allow_ipv6); 687 int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, 688 unsigned int optlen); 689 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, 690 int __user *optlen); 691 int compat_ip_setsockopt(struct sock *sk, int level, int optname, 692 char __user *optval, unsigned int optlen); 693 int compat_ip_getsockopt(struct sock *sk, int level, int optname, 694 char __user *optval, int __user *optlen); 695 int ip_ra_control(struct sock *sk, unsigned char on, 696 void (*destructor)(struct sock *)); 697 698 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len); 699 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, 700 u32 info, u8 *payload); 701 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport, 702 u32 info); 703 704 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb) 705 { 706 ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0); 707 } 708 709 bool icmp_global_allow(void); 710 extern int sysctl_icmp_msgs_per_sec; 711 extern int sysctl_icmp_msgs_burst; 712 713 #ifdef CONFIG_PROC_FS 714 int ip_misc_proc_init(void); 715 #endif 716 717 int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, 718 struct netlink_ext_ack *extack); 719 720 #endif /* _IP_H */ 721