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 extern unsigned int sysctl_fib_sync_mem; 42 extern unsigned int sysctl_fib_sync_mem_min; 43 extern unsigned int sysctl_fib_sync_mem_max; 44 45 struct sock; 46 47 struct inet_skb_parm { 48 int iif; 49 struct ip_options opt; /* Compiled IP options */ 50 u16 flags; 51 52 #define IPSKB_FORWARDED BIT(0) 53 #define IPSKB_XFRM_TUNNEL_SIZE BIT(1) 54 #define IPSKB_XFRM_TRANSFORMED BIT(2) 55 #define IPSKB_FRAG_COMPLETE BIT(3) 56 #define IPSKB_REROUTED BIT(4) 57 #define IPSKB_DOREDIRECT BIT(5) 58 #define IPSKB_FRAG_PMTU BIT(6) 59 #define IPSKB_L3SLAVE BIT(7) 60 61 u16 frag_max_size; 62 }; 63 64 static inline bool ipv4_l3mdev_skb(u16 flags) 65 { 66 return !!(flags & IPSKB_L3SLAVE); 67 } 68 69 static inline unsigned int ip_hdrlen(const struct sk_buff *skb) 70 { 71 return ip_hdr(skb)->ihl * 4; 72 } 73 74 struct ipcm_cookie { 75 struct sockcm_cookie sockc; 76 __be32 addr; 77 int oif; 78 struct ip_options_rcu *opt; 79 __u8 ttl; 80 __s16 tos; 81 char priority; 82 __u16 gso_size; 83 }; 84 85 static inline void ipcm_init(struct ipcm_cookie *ipcm) 86 { 87 *ipcm = (struct ipcm_cookie) { .tos = -1 }; 88 } 89 90 static inline void ipcm_init_sk(struct ipcm_cookie *ipcm, 91 const struct inet_sock *inet) 92 { 93 ipcm_init(ipcm); 94 95 ipcm->sockc.tsflags = inet->sk.sk_tsflags; 96 ipcm->oif = inet->sk.sk_bound_dev_if; 97 ipcm->addr = inet->inet_saddr; 98 } 99 100 #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb)) 101 #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb)) 102 103 /* return enslaved device index if relevant */ 104 static inline int inet_sdif(struct sk_buff *skb) 105 { 106 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV) 107 if (skb && ipv4_l3mdev_skb(IPCB(skb)->flags)) 108 return IPCB(skb)->iif; 109 #endif 110 return 0; 111 } 112 113 /* Special input handler for packets caught by router alert option. 114 They are selected only by protocol field, and then processed likely 115 local ones; but only if someone wants them! Otherwise, router 116 not running rsvpd will kill RSVP. 117 118 It is user level problem, what it will make with them. 119 I have no idea, how it will masquearde or NAT them (it is joke, joke :-)), 120 but receiver should be enough clever f.e. to forward mtrace requests, 121 sent to multicast group to reach destination designated router. 122 */ 123 124 struct ip_ra_chain { 125 struct ip_ra_chain __rcu *next; 126 struct sock *sk; 127 union { 128 void (*destructor)(struct sock *); 129 struct sock *saved_sk; 130 }; 131 struct rcu_head rcu; 132 }; 133 134 /* IP flags. */ 135 #define IP_CE 0x8000 /* Flag: "Congestion" */ 136 #define IP_DF 0x4000 /* Flag: "Don't Fragment" */ 137 #define IP_MF 0x2000 /* Flag: "More Fragments" */ 138 #define IP_OFFSET 0x1FFF /* "Fragment Offset" part */ 139 140 #define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */ 141 142 struct msghdr; 143 struct net_device; 144 struct packet_type; 145 struct rtable; 146 struct sockaddr; 147 148 int igmp_mc_init(void); 149 150 /* 151 * Functions provided by ip.c 152 */ 153 154 int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk, 155 __be32 saddr, __be32 daddr, 156 struct ip_options_rcu *opt); 157 int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, 158 struct net_device *orig_dev); 159 void ip_list_rcv(struct list_head *head, struct packet_type *pt, 160 struct net_device *orig_dev); 161 int ip_local_deliver(struct sk_buff *skb); 162 void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int proto); 163 int ip_mr_input(struct sk_buff *skb); 164 int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb); 165 int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb); 166 int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, 167 int (*output)(struct net *, struct sock *, struct sk_buff *)); 168 void ip_send_check(struct iphdr *ip); 169 int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 170 int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 171 172 int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, 173 __u8 tos); 174 void ip_init(void); 175 int ip_append_data(struct sock *sk, struct flowi4 *fl4, 176 int getfrag(void *from, char *to, int offset, int len, 177 int odd, struct sk_buff *skb), 178 void *from, int len, int protolen, 179 struct ipcm_cookie *ipc, 180 struct rtable **rt, 181 unsigned int flags); 182 int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, 183 struct sk_buff *skb); 184 ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page, 185 int offset, size_t size, int flags); 186 struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4, 187 struct sk_buff_head *queue, 188 struct inet_cork *cork); 189 int ip_send_skb(struct net *net, struct sk_buff *skb); 190 int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4); 191 void ip_flush_pending_frames(struct sock *sk); 192 struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4, 193 int getfrag(void *from, char *to, int offset, 194 int len, int odd, struct sk_buff *skb), 195 void *from, int length, int transhdrlen, 196 struct ipcm_cookie *ipc, struct rtable **rtp, 197 struct inet_cork *cork, unsigned int flags); 198 199 static inline int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, 200 struct flowi *fl) 201 { 202 return __ip_queue_xmit(sk, skb, fl, inet_sk(sk)->tos); 203 } 204 205 static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4) 206 { 207 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base); 208 } 209 210 static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet) 211 { 212 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos); 213 } 214 215 static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk) 216 { 217 return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk); 218 } 219 220 /* datagram.c */ 221 int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); 222 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); 223 224 void ip4_datagram_release_cb(struct sock *sk); 225 226 struct ip_reply_arg { 227 struct kvec iov[1]; 228 int flags; 229 __wsum csum; 230 int csumoffset; /* u16 offset of csum in iov[0].iov_base */ 231 /* -1 if not needed */ 232 int bound_dev_if; 233 u8 tos; 234 kuid_t uid; 235 }; 236 237 #define IP_REPLY_ARG_NOSRCCHECK 1 238 239 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg) 240 { 241 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0; 242 } 243 244 void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb, 245 const struct ip_options *sopt, 246 __be32 daddr, __be32 saddr, 247 const struct ip_reply_arg *arg, 248 unsigned int len); 249 250 #define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field) 251 #define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field) 252 #define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val) 253 #define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val) 254 #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val) 255 #define __IP_UPD_PO_STATS(net, field, val) __SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val) 256 #define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field) 257 #define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field) 258 #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd) 259 #define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd) 260 261 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct); 262 unsigned long snmp_fold_field(void __percpu *mib, int offt); 263 #if BITS_PER_LONG==32 264 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct, 265 size_t syncp_offset); 266 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off); 267 #else 268 static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct, 269 size_t syncp_offset) 270 { 271 return snmp_get_cpu_field(mib, cpu, offct); 272 273 } 274 275 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off) 276 { 277 return snmp_fold_field(mib, offt); 278 } 279 #endif 280 281 #define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \ 282 { \ 283 int i, c; \ 284 for_each_possible_cpu(c) { \ 285 for (i = 0; stats_list[i].name; i++) \ 286 buff64[i] += snmp_get_cpu_field64( \ 287 mib_statistic, \ 288 c, stats_list[i].entry, \ 289 offset); \ 290 } \ 291 } 292 293 #define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \ 294 { \ 295 int i, c; \ 296 for_each_possible_cpu(c) { \ 297 for (i = 0; stats_list[i].name; i++) \ 298 buff[i] += snmp_get_cpu_field( \ 299 mib_statistic, \ 300 c, stats_list[i].entry); \ 301 } \ 302 } 303 304 void inet_get_local_port_range(struct net *net, int *low, int *high); 305 306 #ifdef CONFIG_SYSCTL 307 static inline int inet_is_local_reserved_port(struct net *net, int port) 308 { 309 if (!net->ipv4.sysctl_local_reserved_ports) 310 return 0; 311 return test_bit(port, net->ipv4.sysctl_local_reserved_ports); 312 } 313 314 static inline bool sysctl_dev_name_is_allowed(const char *name) 315 { 316 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0; 317 } 318 319 static inline int inet_prot_sock(struct net *net) 320 { 321 return net->ipv4.sysctl_ip_prot_sock; 322 } 323 324 #else 325 static inline int inet_is_local_reserved_port(struct net *net, int port) 326 { 327 return 0; 328 } 329 330 static inline int inet_prot_sock(struct net *net) 331 { 332 return PROT_SOCK; 333 } 334 #endif 335 336 __be32 inet_current_timestamp(void); 337 338 /* From inetpeer.c */ 339 extern int inet_peer_threshold; 340 extern int inet_peer_minttl; 341 extern int inet_peer_maxttl; 342 343 void ipfrag_init(void); 344 345 void ip_static_sysctl_init(void); 346 347 #define IP4_REPLY_MARK(net, mark) \ 348 ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0) 349 350 static inline bool ip_is_fragment(const struct iphdr *iph) 351 { 352 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0; 353 } 354 355 #ifdef CONFIG_INET 356 #include <net/dst.h> 357 358 /* The function in 2.2 was invalid, producing wrong result for 359 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */ 360 static inline 361 int ip_decrease_ttl(struct iphdr *iph) 362 { 363 u32 check = (__force u32)iph->check; 364 check += (__force u32)htons(0x0100); 365 iph->check = (__force __sum16)(check + (check>=0xFFFF)); 366 return --iph->ttl; 367 } 368 369 static inline int ip_mtu_locked(const struct dst_entry *dst) 370 { 371 const struct rtable *rt = (const struct rtable *)dst; 372 373 return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU); 374 } 375 376 static inline 377 int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst) 378 { 379 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc); 380 381 return pmtudisc == IP_PMTUDISC_DO || 382 (pmtudisc == IP_PMTUDISC_WANT && 383 !ip_mtu_locked(dst)); 384 } 385 386 static inline bool ip_sk_accept_pmtu(const struct sock *sk) 387 { 388 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE && 389 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT; 390 } 391 392 static inline bool ip_sk_use_pmtu(const struct sock *sk) 393 { 394 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE; 395 } 396 397 static inline bool ip_sk_ignore_df(const struct sock *sk) 398 { 399 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO || 400 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT; 401 } 402 403 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, 404 bool forwarding) 405 { 406 struct net *net = dev_net(dst->dev); 407 408 if (net->ipv4.sysctl_ip_fwd_use_pmtu || 409 ip_mtu_locked(dst) || 410 !forwarding) 411 return dst_mtu(dst); 412 413 return min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU); 414 } 415 416 static inline unsigned int ip_skb_dst_mtu(struct sock *sk, 417 const struct sk_buff *skb) 418 { 419 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) { 420 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED; 421 422 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding); 423 } 424 425 return min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU); 426 } 427 428 struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx, 429 int fc_mx_len, 430 struct netlink_ext_ack *extack); 431 static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics) 432 { 433 if (fib_metrics != &dst_default_metrics && 434 refcount_dec_and_test(&fib_metrics->refcnt)) 435 kfree(fib_metrics); 436 } 437 438 /* ipv4 and ipv6 both use refcounted metrics if it is not the default */ 439 static inline 440 void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics) 441 { 442 dst_init_metrics(dst, fib_metrics->metrics, true); 443 444 if (fib_metrics != &dst_default_metrics) { 445 dst->_metrics |= DST_METRICS_REFCOUNTED; 446 refcount_inc(&fib_metrics->refcnt); 447 } 448 } 449 450 static inline 451 void ip_dst_metrics_put(struct dst_entry *dst) 452 { 453 struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst); 454 455 if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt)) 456 kfree(p); 457 } 458 459 u32 ip_idents_reserve(u32 hash, int segs); 460 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs); 461 462 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb, 463 struct sock *sk, int segs) 464 { 465 struct iphdr *iph = ip_hdr(skb); 466 467 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) { 468 /* This is only to work around buggy Windows95/2000 469 * VJ compression implementations. If the ID field 470 * does not change, they drop every other packet in 471 * a TCP stream using header compression. 472 */ 473 if (sk && inet_sk(sk)->inet_daddr) { 474 iph->id = htons(inet_sk(sk)->inet_id); 475 inet_sk(sk)->inet_id += segs; 476 } else { 477 iph->id = 0; 478 } 479 } else { 480 __ip_select_ident(net, iph, segs); 481 } 482 } 483 484 static inline void ip_select_ident(struct net *net, struct sk_buff *skb, 485 struct sock *sk) 486 { 487 ip_select_ident_segs(net, skb, sk, 1); 488 } 489 490 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto) 491 { 492 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, 493 skb->len, proto, 0); 494 } 495 496 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store 497 * Equivalent to : flow->v4addrs.src = iph->saddr; 498 * flow->v4addrs.dst = iph->daddr; 499 */ 500 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow, 501 const struct iphdr *iph) 502 { 503 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) != 504 offsetof(typeof(flow->addrs), v4addrs.src) + 505 sizeof(flow->addrs.v4addrs.src)); 506 memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs)); 507 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; 508 } 509 510 static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto) 511 { 512 const struct iphdr *iph = skb_gro_network_header(skb); 513 514 return csum_tcpudp_nofold(iph->saddr, iph->daddr, 515 skb_gro_len(skb), proto, 0); 516 } 517 518 /* 519 * Map a multicast IP onto multicast MAC for type ethernet. 520 */ 521 522 static inline void ip_eth_mc_map(__be32 naddr, char *buf) 523 { 524 __u32 addr=ntohl(naddr); 525 buf[0]=0x01; 526 buf[1]=0x00; 527 buf[2]=0x5e; 528 buf[5]=addr&0xFF; 529 addr>>=8; 530 buf[4]=addr&0xFF; 531 addr>>=8; 532 buf[3]=addr&0x7F; 533 } 534 535 /* 536 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand. 537 * Leave P_Key as 0 to be filled in by driver. 538 */ 539 540 static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) 541 { 542 __u32 addr; 543 unsigned char scope = broadcast[5] & 0xF; 544 545 buf[0] = 0; /* Reserved */ 546 buf[1] = 0xff; /* Multicast QPN */ 547 buf[2] = 0xff; 548 buf[3] = 0xff; 549 addr = ntohl(naddr); 550 buf[4] = 0xff; 551 buf[5] = 0x10 | scope; /* scope from broadcast address */ 552 buf[6] = 0x40; /* IPv4 signature */ 553 buf[7] = 0x1b; 554 buf[8] = broadcast[8]; /* P_Key */ 555 buf[9] = broadcast[9]; 556 buf[10] = 0; 557 buf[11] = 0; 558 buf[12] = 0; 559 buf[13] = 0; 560 buf[14] = 0; 561 buf[15] = 0; 562 buf[19] = addr & 0xff; 563 addr >>= 8; 564 buf[18] = addr & 0xff; 565 addr >>= 8; 566 buf[17] = addr & 0xff; 567 addr >>= 8; 568 buf[16] = addr & 0x0f; 569 } 570 571 static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) 572 { 573 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0) 574 memcpy(buf, broadcast, 4); 575 else 576 memcpy(buf, &naddr, sizeof(naddr)); 577 } 578 579 #if IS_ENABLED(CONFIG_IPV6) 580 #include <linux/ipv6.h> 581 #endif 582 583 static __inline__ void inet_reset_saddr(struct sock *sk) 584 { 585 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0; 586 #if IS_ENABLED(CONFIG_IPV6) 587 if (sk->sk_family == PF_INET6) { 588 struct ipv6_pinfo *np = inet6_sk(sk); 589 590 memset(&np->saddr, 0, sizeof(np->saddr)); 591 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr)); 592 } 593 #endif 594 } 595 596 #endif 597 598 static inline unsigned int ipv4_addr_hash(__be32 ip) 599 { 600 return (__force unsigned int) ip; 601 } 602 603 static inline u32 ipv4_portaddr_hash(const struct net *net, 604 __be32 saddr, 605 unsigned int port) 606 { 607 return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port; 608 } 609 610 bool ip_call_ra_chain(struct sk_buff *skb); 611 612 /* 613 * Functions provided by ip_fragment.c 614 */ 615 616 enum ip_defrag_users { 617 IP_DEFRAG_LOCAL_DELIVER, 618 IP_DEFRAG_CALL_RA_CHAIN, 619 IP_DEFRAG_CONNTRACK_IN, 620 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX, 621 IP_DEFRAG_CONNTRACK_OUT, 622 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX, 623 IP_DEFRAG_CONNTRACK_BRIDGE_IN, 624 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX, 625 IP_DEFRAG_VS_IN, 626 IP_DEFRAG_VS_OUT, 627 IP_DEFRAG_VS_FWD, 628 IP_DEFRAG_AF_PACKET, 629 IP_DEFRAG_MACVLAN, 630 }; 631 632 /* Return true if the value of 'user' is between 'lower_bond' 633 * and 'upper_bond' inclusively. 634 */ 635 static inline bool ip_defrag_user_in_between(u32 user, 636 enum ip_defrag_users lower_bond, 637 enum ip_defrag_users upper_bond) 638 { 639 return user >= lower_bond && user <= upper_bond; 640 } 641 642 int ip_defrag(struct net *net, struct sk_buff *skb, u32 user); 643 #ifdef CONFIG_INET 644 struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user); 645 #else 646 static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user) 647 { 648 return skb; 649 } 650 #endif 651 652 /* 653 * Functions provided by ip_forward.c 654 */ 655 656 int ip_forward(struct sk_buff *skb); 657 658 /* 659 * Functions provided by ip_options.c 660 */ 661 662 void ip_options_build(struct sk_buff *skb, struct ip_options *opt, 663 __be32 daddr, struct rtable *rt, int is_frag); 664 665 int __ip_options_echo(struct net *net, struct ip_options *dopt, 666 struct sk_buff *skb, const struct ip_options *sopt); 667 static inline int ip_options_echo(struct net *net, struct ip_options *dopt, 668 struct sk_buff *skb) 669 { 670 return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt); 671 } 672 673 void ip_options_fragment(struct sk_buff *skb); 674 int __ip_options_compile(struct net *net, struct ip_options *opt, 675 struct sk_buff *skb, __be32 *info); 676 int ip_options_compile(struct net *net, struct ip_options *opt, 677 struct sk_buff *skb); 678 int ip_options_get(struct net *net, struct ip_options_rcu **optp, 679 unsigned char *data, int optlen); 680 int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp, 681 unsigned char __user *data, int optlen); 682 void ip_options_undo(struct ip_options *opt); 683 void ip_forward_options(struct sk_buff *skb); 684 int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev); 685 686 /* 687 * Functions provided by ip_sockglue.c 688 */ 689 690 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb); 691 void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk, 692 struct sk_buff *skb, int tlen, int offset); 693 int ip_cmsg_send(struct sock *sk, struct msghdr *msg, 694 struct ipcm_cookie *ipc, bool allow_ipv6); 695 int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, 696 unsigned int optlen); 697 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, 698 int __user *optlen); 699 int compat_ip_setsockopt(struct sock *sk, int level, int optname, 700 char __user *optval, unsigned int optlen); 701 int compat_ip_getsockopt(struct sock *sk, int level, int optname, 702 char __user *optval, int __user *optlen); 703 int ip_ra_control(struct sock *sk, unsigned char on, 704 void (*destructor)(struct sock *)); 705 706 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len); 707 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, 708 u32 info, u8 *payload); 709 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport, 710 u32 info); 711 712 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb) 713 { 714 ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0); 715 } 716 717 bool icmp_global_allow(void); 718 extern int sysctl_icmp_msgs_per_sec; 719 extern int sysctl_icmp_msgs_burst; 720 721 #ifdef CONFIG_PROC_FS 722 int ip_misc_proc_init(void); 723 #endif 724 725 int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family, 726 struct netlink_ext_ack *extack); 727 728 #endif /* _IP_H */ 729