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, <[email protected]> 12 * Alan Cox, <[email protected]> 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 *)); 168 169 struct ip_fraglist_iter { 170 struct sk_buff *frag_list; 171 struct sk_buff *frag; 172 struct iphdr *iph; 173 int offset; 174 unsigned int hlen; 175 }; 176 177 void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph, 178 unsigned int hlen, struct ip_fraglist_iter *iter); 179 void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter); 180 181 static inline struct sk_buff *ip_fraglist_next(struct ip_fraglist_iter *iter) 182 { 183 struct sk_buff *skb = iter->frag; 184 185 iter->frag = skb->next; 186 skb_mark_not_on_list(skb); 187 188 return skb; 189 } 190 191 struct ip_frag_state { 192 struct iphdr *iph; 193 unsigned int hlen; 194 unsigned int ll_rs; 195 unsigned int mtu; 196 unsigned int left; 197 int offset; 198 int ptr; 199 __be16 not_last_frag; 200 }; 201 202 void ip_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int ll_rs, 203 unsigned int mtu, struct ip_frag_state *state); 204 struct sk_buff *ip_frag_next(struct sk_buff *skb, 205 struct ip_frag_state *state); 206 207 void ip_send_check(struct iphdr *ip); 208 int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 209 int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 210 211 int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, 212 __u8 tos); 213 void ip_init(void); 214 int ip_append_data(struct sock *sk, struct flowi4 *fl4, 215 int getfrag(void *from, char *to, int offset, int len, 216 int odd, struct sk_buff *skb), 217 void *from, int len, int protolen, 218 struct ipcm_cookie *ipc, 219 struct rtable **rt, 220 unsigned int flags); 221 int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, 222 struct sk_buff *skb); 223 ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page, 224 int offset, size_t size, int flags); 225 struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4, 226 struct sk_buff_head *queue, 227 struct inet_cork *cork); 228 int ip_send_skb(struct net *net, struct sk_buff *skb); 229 int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4); 230 void ip_flush_pending_frames(struct sock *sk); 231 struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4, 232 int getfrag(void *from, char *to, int offset, 233 int len, int odd, struct sk_buff *skb), 234 void *from, int length, int transhdrlen, 235 struct ipcm_cookie *ipc, struct rtable **rtp, 236 struct inet_cork *cork, unsigned int flags); 237 238 static inline int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, 239 struct flowi *fl) 240 { 241 return __ip_queue_xmit(sk, skb, fl, inet_sk(sk)->tos); 242 } 243 244 static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4) 245 { 246 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base); 247 } 248 249 static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet) 250 { 251 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos); 252 } 253 254 static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk) 255 { 256 return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk); 257 } 258 259 /* datagram.c */ 260 int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); 261 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); 262 263 void ip4_datagram_release_cb(struct sock *sk); 264 265 struct ip_reply_arg { 266 struct kvec iov[1]; 267 int flags; 268 __wsum csum; 269 int csumoffset; /* u16 offset of csum in iov[0].iov_base */ 270 /* -1 if not needed */ 271 int bound_dev_if; 272 u8 tos; 273 kuid_t uid; 274 }; 275 276 #define IP_REPLY_ARG_NOSRCCHECK 1 277 278 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg) 279 { 280 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0; 281 } 282 283 void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb, 284 const struct ip_options *sopt, 285 __be32 daddr, __be32 saddr, 286 const struct ip_reply_arg *arg, 287 unsigned int len); 288 289 #define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field) 290 #define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field) 291 #define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val) 292 #define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val) 293 #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val) 294 #define __IP_UPD_PO_STATS(net, field, val) __SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val) 295 #define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field) 296 #define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field) 297 #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd) 298 #define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd) 299 300 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct); 301 unsigned long snmp_fold_field(void __percpu *mib, int offt); 302 #if BITS_PER_LONG==32 303 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct, 304 size_t syncp_offset); 305 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off); 306 #else 307 static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct, 308 size_t syncp_offset) 309 { 310 return snmp_get_cpu_field(mib, cpu, offct); 311 312 } 313 314 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off) 315 { 316 return snmp_fold_field(mib, offt); 317 } 318 #endif 319 320 #define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \ 321 { \ 322 int i, c; \ 323 for_each_possible_cpu(c) { \ 324 for (i = 0; stats_list[i].name; i++) \ 325 buff64[i] += snmp_get_cpu_field64( \ 326 mib_statistic, \ 327 c, stats_list[i].entry, \ 328 offset); \ 329 } \ 330 } 331 332 #define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \ 333 { \ 334 int i, c; \ 335 for_each_possible_cpu(c) { \ 336 for (i = 0; stats_list[i].name; i++) \ 337 buff[i] += snmp_get_cpu_field( \ 338 mib_statistic, \ 339 c, stats_list[i].entry); \ 340 } \ 341 } 342 343 void inet_get_local_port_range(struct net *net, int *low, int *high); 344 345 #ifdef CONFIG_SYSCTL 346 static inline int inet_is_local_reserved_port(struct net *net, int port) 347 { 348 if (!net->ipv4.sysctl_local_reserved_ports) 349 return 0; 350 return test_bit(port, net->ipv4.sysctl_local_reserved_ports); 351 } 352 353 static inline bool sysctl_dev_name_is_allowed(const char *name) 354 { 355 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0; 356 } 357 358 static inline int inet_prot_sock(struct net *net) 359 { 360 return net->ipv4.sysctl_ip_prot_sock; 361 } 362 363 #else 364 static inline int inet_is_local_reserved_port(struct net *net, int port) 365 { 366 return 0; 367 } 368 369 static inline int inet_prot_sock(struct net *net) 370 { 371 return PROT_SOCK; 372 } 373 #endif 374 375 __be32 inet_current_timestamp(void); 376 377 /* From inetpeer.c */ 378 extern int inet_peer_threshold; 379 extern int inet_peer_minttl; 380 extern int inet_peer_maxttl; 381 382 void ipfrag_init(void); 383 384 void ip_static_sysctl_init(void); 385 386 #define IP4_REPLY_MARK(net, mark) \ 387 ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0) 388 389 static inline bool ip_is_fragment(const struct iphdr *iph) 390 { 391 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0; 392 } 393 394 #ifdef CONFIG_INET 395 #include <net/dst.h> 396 397 /* The function in 2.2 was invalid, producing wrong result for 398 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */ 399 static inline 400 int ip_decrease_ttl(struct iphdr *iph) 401 { 402 u32 check = (__force u32)iph->check; 403 check += (__force u32)htons(0x0100); 404 iph->check = (__force __sum16)(check + (check>=0xFFFF)); 405 return --iph->ttl; 406 } 407 408 static inline int ip_mtu_locked(const struct dst_entry *dst) 409 { 410 const struct rtable *rt = (const struct rtable *)dst; 411 412 return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU); 413 } 414 415 static inline 416 int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst) 417 { 418 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc); 419 420 return pmtudisc == IP_PMTUDISC_DO || 421 (pmtudisc == IP_PMTUDISC_WANT && 422 !ip_mtu_locked(dst)); 423 } 424 425 static inline bool ip_sk_accept_pmtu(const struct sock *sk) 426 { 427 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE && 428 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT; 429 } 430 431 static inline bool ip_sk_use_pmtu(const struct sock *sk) 432 { 433 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE; 434 } 435 436 static inline bool ip_sk_ignore_df(const struct sock *sk) 437 { 438 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO || 439 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT; 440 } 441 442 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, 443 bool forwarding) 444 { 445 struct net *net = dev_net(dst->dev); 446 447 if (net->ipv4.sysctl_ip_fwd_use_pmtu || 448 ip_mtu_locked(dst) || 449 !forwarding) 450 return dst_mtu(dst); 451 452 return min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU); 453 } 454 455 static inline unsigned int ip_skb_dst_mtu(struct sock *sk, 456 const struct sk_buff *skb) 457 { 458 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) { 459 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED; 460 461 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding); 462 } 463 464 return min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU); 465 } 466 467 struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx, 468 int fc_mx_len, 469 struct netlink_ext_ack *extack); 470 static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics) 471 { 472 if (fib_metrics != &dst_default_metrics && 473 refcount_dec_and_test(&fib_metrics->refcnt)) 474 kfree(fib_metrics); 475 } 476 477 /* ipv4 and ipv6 both use refcounted metrics if it is not the default */ 478 static inline 479 void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics) 480 { 481 dst_init_metrics(dst, fib_metrics->metrics, true); 482 483 if (fib_metrics != &dst_default_metrics) { 484 dst->_metrics |= DST_METRICS_REFCOUNTED; 485 refcount_inc(&fib_metrics->refcnt); 486 } 487 } 488 489 static inline 490 void ip_dst_metrics_put(struct dst_entry *dst) 491 { 492 struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst); 493 494 if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt)) 495 kfree(p); 496 } 497 498 u32 ip_idents_reserve(u32 hash, int segs); 499 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs); 500 501 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb, 502 struct sock *sk, int segs) 503 { 504 struct iphdr *iph = ip_hdr(skb); 505 506 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) { 507 /* This is only to work around buggy Windows95/2000 508 * VJ compression implementations. If the ID field 509 * does not change, they drop every other packet in 510 * a TCP stream using header compression. 511 */ 512 if (sk && inet_sk(sk)->inet_daddr) { 513 iph->id = htons(inet_sk(sk)->inet_id); 514 inet_sk(sk)->inet_id += segs; 515 } else { 516 iph->id = 0; 517 } 518 } else { 519 __ip_select_ident(net, iph, segs); 520 } 521 } 522 523 static inline void ip_select_ident(struct net *net, struct sk_buff *skb, 524 struct sock *sk) 525 { 526 ip_select_ident_segs(net, skb, sk, 1); 527 } 528 529 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto) 530 { 531 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, 532 skb->len, proto, 0); 533 } 534 535 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store 536 * Equivalent to : flow->v4addrs.src = iph->saddr; 537 * flow->v4addrs.dst = iph->daddr; 538 */ 539 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow, 540 const struct iphdr *iph) 541 { 542 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) != 543 offsetof(typeof(flow->addrs), v4addrs.src) + 544 sizeof(flow->addrs.v4addrs.src)); 545 memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs)); 546 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; 547 } 548 549 static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto) 550 { 551 const struct iphdr *iph = skb_gro_network_header(skb); 552 553 return csum_tcpudp_nofold(iph->saddr, iph->daddr, 554 skb_gro_len(skb), proto, 0); 555 } 556 557 /* 558 * Map a multicast IP onto multicast MAC for type ethernet. 559 */ 560 561 static inline void ip_eth_mc_map(__be32 naddr, char *buf) 562 { 563 __u32 addr=ntohl(naddr); 564 buf[0]=0x01; 565 buf[1]=0x00; 566 buf[2]=0x5e; 567 buf[5]=addr&0xFF; 568 addr>>=8; 569 buf[4]=addr&0xFF; 570 addr>>=8; 571 buf[3]=addr&0x7F; 572 } 573 574 /* 575 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand. 576 * Leave P_Key as 0 to be filled in by driver. 577 */ 578 579 static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) 580 { 581 __u32 addr; 582 unsigned char scope = broadcast[5] & 0xF; 583 584 buf[0] = 0; /* Reserved */ 585 buf[1] = 0xff; /* Multicast QPN */ 586 buf[2] = 0xff; 587 buf[3] = 0xff; 588 addr = ntohl(naddr); 589 buf[4] = 0xff; 590 buf[5] = 0x10 | scope; /* scope from broadcast address */ 591 buf[6] = 0x40; /* IPv4 signature */ 592 buf[7] = 0x1b; 593 buf[8] = broadcast[8]; /* P_Key */ 594 buf[9] = broadcast[9]; 595 buf[10] = 0; 596 buf[11] = 0; 597 buf[12] = 0; 598 buf[13] = 0; 599 buf[14] = 0; 600 buf[15] = 0; 601 buf[19] = addr & 0xff; 602 addr >>= 8; 603 buf[18] = addr & 0xff; 604 addr >>= 8; 605 buf[17] = addr & 0xff; 606 addr >>= 8; 607 buf[16] = addr & 0x0f; 608 } 609 610 static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) 611 { 612 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0) 613 memcpy(buf, broadcast, 4); 614 else 615 memcpy(buf, &naddr, sizeof(naddr)); 616 } 617 618 #if IS_ENABLED(CONFIG_IPV6) 619 #include <linux/ipv6.h> 620 #endif 621 622 static __inline__ void inet_reset_saddr(struct sock *sk) 623 { 624 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0; 625 #if IS_ENABLED(CONFIG_IPV6) 626 if (sk->sk_family == PF_INET6) { 627 struct ipv6_pinfo *np = inet6_sk(sk); 628 629 memset(&np->saddr, 0, sizeof(np->saddr)); 630 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr)); 631 } 632 #endif 633 } 634 635 #endif 636 637 static inline unsigned int ipv4_addr_hash(__be32 ip) 638 { 639 return (__force unsigned int) ip; 640 } 641 642 static inline u32 ipv4_portaddr_hash(const struct net *net, 643 __be32 saddr, 644 unsigned int port) 645 { 646 return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port; 647 } 648 649 bool ip_call_ra_chain(struct sk_buff *skb); 650 651 /* 652 * Functions provided by ip_fragment.c 653 */ 654 655 enum ip_defrag_users { 656 IP_DEFRAG_LOCAL_DELIVER, 657 IP_DEFRAG_CALL_RA_CHAIN, 658 IP_DEFRAG_CONNTRACK_IN, 659 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX, 660 IP_DEFRAG_CONNTRACK_OUT, 661 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX, 662 IP_DEFRAG_CONNTRACK_BRIDGE_IN, 663 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX, 664 IP_DEFRAG_VS_IN, 665 IP_DEFRAG_VS_OUT, 666 IP_DEFRAG_VS_FWD, 667 IP_DEFRAG_AF_PACKET, 668 IP_DEFRAG_MACVLAN, 669 }; 670 671 /* Return true if the value of 'user' is between 'lower_bond' 672 * and 'upper_bond' inclusively. 673 */ 674 static inline bool ip_defrag_user_in_between(u32 user, 675 enum ip_defrag_users lower_bond, 676 enum ip_defrag_users upper_bond) 677 { 678 return user >= lower_bond && user <= upper_bond; 679 } 680 681 int ip_defrag(struct net *net, struct sk_buff *skb, u32 user); 682 #ifdef CONFIG_INET 683 struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user); 684 #else 685 static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user) 686 { 687 return skb; 688 } 689 #endif 690 691 /* 692 * Functions provided by ip_forward.c 693 */ 694 695 int ip_forward(struct sk_buff *skb); 696 697 /* 698 * Functions provided by ip_options.c 699 */ 700 701 void ip_options_build(struct sk_buff *skb, struct ip_options *opt, 702 __be32 daddr, struct rtable *rt, int is_frag); 703 704 int __ip_options_echo(struct net *net, struct ip_options *dopt, 705 struct sk_buff *skb, const struct ip_options *sopt); 706 static inline int ip_options_echo(struct net *net, struct ip_options *dopt, 707 struct sk_buff *skb) 708 { 709 return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt); 710 } 711 712 void ip_options_fragment(struct sk_buff *skb); 713 int __ip_options_compile(struct net *net, struct ip_options *opt, 714 struct sk_buff *skb, __be32 *info); 715 int ip_options_compile(struct net *net, struct ip_options *opt, 716 struct sk_buff *skb); 717 int ip_options_get(struct net *net, struct ip_options_rcu **optp, 718 unsigned char *data, int optlen); 719 int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp, 720 unsigned char __user *data, int optlen); 721 void ip_options_undo(struct ip_options *opt); 722 void ip_forward_options(struct sk_buff *skb); 723 int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev); 724 725 /* 726 * Functions provided by ip_sockglue.c 727 */ 728 729 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb); 730 void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk, 731 struct sk_buff *skb, int tlen, int offset); 732 int ip_cmsg_send(struct sock *sk, struct msghdr *msg, 733 struct ipcm_cookie *ipc, bool allow_ipv6); 734 int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, 735 unsigned int optlen); 736 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, 737 int __user *optlen); 738 int compat_ip_setsockopt(struct sock *sk, int level, int optname, 739 char __user *optval, unsigned int optlen); 740 int compat_ip_getsockopt(struct sock *sk, int level, int optname, 741 char __user *optval, int __user *optlen); 742 int ip_ra_control(struct sock *sk, unsigned char on, 743 void (*destructor)(struct sock *)); 744 745 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len); 746 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, 747 u32 info, u8 *payload); 748 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport, 749 u32 info); 750 751 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb) 752 { 753 ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0); 754 } 755 756 bool icmp_global_allow(void); 757 extern int sysctl_icmp_msgs_per_sec; 758 extern int sysctl_icmp_msgs_burst; 759 760 #ifdef CONFIG_PROC_FS 761 int ip_misc_proc_init(void); 762 #endif 763 764 int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family, 765 struct netlink_ext_ack *extack); 766 767 #endif /* _IP_H */ 768