1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * INET An implementation of the TCP/IP protocol suite for the LINUX 4 * operating system. INET is implemented using the BSD Socket 5 * interface as the means of communication with the user level. 6 * 7 * Definitions for the IP module. 8 * 9 * Version: @(#)ip.h 1.0.2 05/07/93 10 * 11 * Authors: Ross Biro 12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 13 * Alan Cox, <gw4pts@gw4pts.ampr.org> 14 * 15 * Changes: 16 * Mike McLagan : Routing by source 17 */ 18 #ifndef _IP_H 19 #define _IP_H 20 21 #include <linux/types.h> 22 #include <linux/ip.h> 23 #include <linux/in.h> 24 #include <linux/skbuff.h> 25 #include <linux/jhash.h> 26 27 #include <net/inet_sock.h> 28 #include <net/route.h> 29 #include <net/snmp.h> 30 #include <net/flow.h> 31 #include <net/flow_dissector.h> 32 #include <net/netns/hash.h> 33 34 #define IPV4_MAX_PMTU 65535U /* RFC 2675, Section 5.1 */ 35 #define IPV4_MIN_MTU 68 /* RFC 791 */ 36 37 extern unsigned int sysctl_fib_sync_mem; 38 extern unsigned int sysctl_fib_sync_mem_min; 39 extern unsigned int sysctl_fib_sync_mem_max; 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.mark = inet->sk.sk_mark; 92 ipcm->sockc.tsflags = inet->sk.sk_tsflags; 93 ipcm->oif = inet->sk.sk_bound_dev_if; 94 ipcm->addr = inet->inet_saddr; 95 } 96 97 #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb)) 98 #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb)) 99 100 /* return enslaved device index if relevant */ 101 static inline int inet_sdif(struct sk_buff *skb) 102 { 103 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV) 104 if (skb && ipv4_l3mdev_skb(IPCB(skb)->flags)) 105 return IPCB(skb)->iif; 106 #endif 107 return 0; 108 } 109 110 /* Special input handler for packets caught by router alert option. 111 They are selected only by protocol field, and then processed likely 112 local ones; but only if someone wants them! Otherwise, router 113 not running rsvpd will kill RSVP. 114 115 It is user level problem, what it will make with them. 116 I have no idea, how it will masquearde or NAT them (it is joke, joke :-)), 117 but receiver should be enough clever f.e. to forward mtrace requests, 118 sent to multicast group to reach destination designated router. 119 */ 120 121 struct ip_ra_chain { 122 struct ip_ra_chain __rcu *next; 123 struct sock *sk; 124 union { 125 void (*destructor)(struct sock *); 126 struct sock *saved_sk; 127 }; 128 struct rcu_head rcu; 129 }; 130 131 /* IP flags. */ 132 #define IP_CE 0x8000 /* Flag: "Congestion" */ 133 #define IP_DF 0x4000 /* Flag: "Don't Fragment" */ 134 #define IP_MF 0x2000 /* Flag: "More Fragments" */ 135 #define IP_OFFSET 0x1FFF /* "Fragment Offset" part */ 136 137 #define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */ 138 139 struct msghdr; 140 struct net_device; 141 struct packet_type; 142 struct rtable; 143 struct sockaddr; 144 145 int igmp_mc_init(void); 146 147 /* 148 * Functions provided by ip.c 149 */ 150 151 int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk, 152 __be32 saddr, __be32 daddr, 153 struct ip_options_rcu *opt); 154 int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, 155 struct net_device *orig_dev); 156 void ip_list_rcv(struct list_head *head, struct packet_type *pt, 157 struct net_device *orig_dev); 158 int ip_local_deliver(struct sk_buff *skb); 159 void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int proto); 160 int ip_mr_input(struct sk_buff *skb); 161 int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb); 162 int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb); 163 int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, 164 int (*output)(struct net *, struct sock *, struct sk_buff *)); 165 166 struct ip_fraglist_iter { 167 struct sk_buff *frag; 168 struct iphdr *iph; 169 int offset; 170 unsigned int hlen; 171 }; 172 173 void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph, 174 unsigned int hlen, struct ip_fraglist_iter *iter); 175 void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter); 176 177 static inline struct sk_buff *ip_fraglist_next(struct ip_fraglist_iter *iter) 178 { 179 struct sk_buff *skb = iter->frag; 180 181 iter->frag = skb->next; 182 skb_mark_not_on_list(skb); 183 184 return skb; 185 } 186 187 struct ip_frag_state { 188 bool DF; 189 unsigned int hlen; 190 unsigned int ll_rs; 191 unsigned int mtu; 192 unsigned int left; 193 int offset; 194 int ptr; 195 __be16 not_last_frag; 196 }; 197 198 void ip_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int ll_rs, 199 unsigned int mtu, bool DF, struct ip_frag_state *state); 200 struct sk_buff *ip_frag_next(struct sk_buff *skb, 201 struct ip_frag_state *state); 202 203 void ip_send_check(struct iphdr *ip); 204 int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 205 int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 206 207 int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, 208 __u8 tos); 209 void ip_init(void); 210 int ip_append_data(struct sock *sk, struct flowi4 *fl4, 211 int getfrag(void *from, char *to, int offset, int len, 212 int odd, struct sk_buff *skb), 213 void *from, int len, int protolen, 214 struct ipcm_cookie *ipc, 215 struct rtable **rt, 216 unsigned int flags); 217 int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, 218 struct sk_buff *skb); 219 ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page, 220 int offset, size_t size, int flags); 221 struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4, 222 struct sk_buff_head *queue, 223 struct inet_cork *cork); 224 int ip_send_skb(struct net *net, struct sk_buff *skb); 225 int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4); 226 void ip_flush_pending_frames(struct sock *sk); 227 struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4, 228 int getfrag(void *from, char *to, int offset, 229 int len, int odd, struct sk_buff *skb), 230 void *from, int length, int transhdrlen, 231 struct ipcm_cookie *ipc, struct rtable **rtp, 232 struct inet_cork *cork, unsigned int flags); 233 234 static inline int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, 235 struct flowi *fl) 236 { 237 return __ip_queue_xmit(sk, skb, fl, inet_sk(sk)->tos); 238 } 239 240 static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4) 241 { 242 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base); 243 } 244 245 static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet) 246 { 247 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos); 248 } 249 250 static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk) 251 { 252 return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk); 253 } 254 255 /* datagram.c */ 256 int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); 257 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); 258 259 void ip4_datagram_release_cb(struct sock *sk); 260 261 struct ip_reply_arg { 262 struct kvec iov[1]; 263 int flags; 264 __wsum csum; 265 int csumoffset; /* u16 offset of csum in iov[0].iov_base */ 266 /* -1 if not needed */ 267 int bound_dev_if; 268 u8 tos; 269 kuid_t uid; 270 }; 271 272 #define IP_REPLY_ARG_NOSRCCHECK 1 273 274 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg) 275 { 276 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0; 277 } 278 279 void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb, 280 const struct ip_options *sopt, 281 __be32 daddr, __be32 saddr, 282 const struct ip_reply_arg *arg, 283 unsigned int len, u64 transmit_time); 284 285 #define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field) 286 #define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field) 287 #define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val) 288 #define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val) 289 #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val) 290 #define __IP_UPD_PO_STATS(net, field, val) __SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val) 291 #define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field) 292 #define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field) 293 #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd) 294 #define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd) 295 296 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct); 297 unsigned long snmp_fold_field(void __percpu *mib, int offt); 298 #if BITS_PER_LONG==32 299 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct, 300 size_t syncp_offset); 301 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off); 302 #else 303 static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct, 304 size_t syncp_offset) 305 { 306 return snmp_get_cpu_field(mib, cpu, offct); 307 308 } 309 310 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off) 311 { 312 return snmp_fold_field(mib, offt); 313 } 314 #endif 315 316 #define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \ 317 { \ 318 int i, c; \ 319 for_each_possible_cpu(c) { \ 320 for (i = 0; stats_list[i].name; i++) \ 321 buff64[i] += snmp_get_cpu_field64( \ 322 mib_statistic, \ 323 c, stats_list[i].entry, \ 324 offset); \ 325 } \ 326 } 327 328 #define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \ 329 { \ 330 int i, c; \ 331 for_each_possible_cpu(c) { \ 332 for (i = 0; stats_list[i].name; i++) \ 333 buff[i] += snmp_get_cpu_field( \ 334 mib_statistic, \ 335 c, stats_list[i].entry); \ 336 } \ 337 } 338 339 void inet_get_local_port_range(struct net *net, int *low, int *high); 340 341 #ifdef CONFIG_SYSCTL 342 static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port) 343 { 344 if (!net->ipv4.sysctl_local_reserved_ports) 345 return false; 346 return test_bit(port, net->ipv4.sysctl_local_reserved_ports); 347 } 348 349 static inline bool sysctl_dev_name_is_allowed(const char *name) 350 { 351 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0; 352 } 353 354 static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port) 355 { 356 return port < net->ipv4.sysctl_ip_prot_sock; 357 } 358 359 #else 360 static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port) 361 { 362 return false; 363 } 364 365 static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port) 366 { 367 return port < PROT_SOCK; 368 } 369 #endif 370 371 __be32 inet_current_timestamp(void); 372 373 /* From inetpeer.c */ 374 extern int inet_peer_threshold; 375 extern int inet_peer_minttl; 376 extern int inet_peer_maxttl; 377 378 void ipfrag_init(void); 379 380 void ip_static_sysctl_init(void); 381 382 #define IP4_REPLY_MARK(net, mark) \ 383 ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0) 384 385 static inline bool ip_is_fragment(const struct iphdr *iph) 386 { 387 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0; 388 } 389 390 #ifdef CONFIG_INET 391 #include <net/dst.h> 392 393 /* The function in 2.2 was invalid, producing wrong result for 394 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */ 395 static inline 396 int ip_decrease_ttl(struct iphdr *iph) 397 { 398 u32 check = (__force u32)iph->check; 399 check += (__force u32)htons(0x0100); 400 iph->check = (__force __sum16)(check + (check>=0xFFFF)); 401 return --iph->ttl; 402 } 403 404 static inline int ip_mtu_locked(const struct dst_entry *dst) 405 { 406 const struct rtable *rt = (const struct rtable *)dst; 407 408 return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU); 409 } 410 411 static inline 412 int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst) 413 { 414 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc); 415 416 return pmtudisc == IP_PMTUDISC_DO || 417 (pmtudisc == IP_PMTUDISC_WANT && 418 !ip_mtu_locked(dst)); 419 } 420 421 static inline bool ip_sk_accept_pmtu(const struct sock *sk) 422 { 423 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE && 424 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT; 425 } 426 427 static inline bool ip_sk_use_pmtu(const struct sock *sk) 428 { 429 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE; 430 } 431 432 static inline bool ip_sk_ignore_df(const struct sock *sk) 433 { 434 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO || 435 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT; 436 } 437 438 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, 439 bool forwarding) 440 { 441 struct net *net = dev_net(dst->dev); 442 443 if (net->ipv4.sysctl_ip_fwd_use_pmtu || 444 ip_mtu_locked(dst) || 445 !forwarding) 446 return dst_mtu(dst); 447 448 return min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU); 449 } 450 451 static inline unsigned int ip_skb_dst_mtu(struct sock *sk, 452 const struct sk_buff *skb) 453 { 454 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) { 455 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED; 456 457 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding); 458 } 459 460 return min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU); 461 } 462 463 struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx, 464 int fc_mx_len, 465 struct netlink_ext_ack *extack); 466 static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics) 467 { 468 if (fib_metrics != &dst_default_metrics && 469 refcount_dec_and_test(&fib_metrics->refcnt)) 470 kfree(fib_metrics); 471 } 472 473 /* ipv4 and ipv6 both use refcounted metrics if it is not the default */ 474 static inline 475 void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics) 476 { 477 dst_init_metrics(dst, fib_metrics->metrics, true); 478 479 if (fib_metrics != &dst_default_metrics) { 480 dst->_metrics |= DST_METRICS_REFCOUNTED; 481 refcount_inc(&fib_metrics->refcnt); 482 } 483 } 484 485 static inline 486 void ip_dst_metrics_put(struct dst_entry *dst) 487 { 488 struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst); 489 490 if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt)) 491 kfree(p); 492 } 493 494 u32 ip_idents_reserve(u32 hash, int segs); 495 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs); 496 497 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb, 498 struct sock *sk, int segs) 499 { 500 struct iphdr *iph = ip_hdr(skb); 501 502 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) { 503 /* This is only to work around buggy Windows95/2000 504 * VJ compression implementations. If the ID field 505 * does not change, they drop every other packet in 506 * a TCP stream using header compression. 507 */ 508 if (sk && inet_sk(sk)->inet_daddr) { 509 iph->id = htons(inet_sk(sk)->inet_id); 510 inet_sk(sk)->inet_id += segs; 511 } else { 512 iph->id = 0; 513 } 514 } else { 515 __ip_select_ident(net, iph, segs); 516 } 517 } 518 519 static inline void ip_select_ident(struct net *net, struct sk_buff *skb, 520 struct sock *sk) 521 { 522 ip_select_ident_segs(net, skb, sk, 1); 523 } 524 525 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto) 526 { 527 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, 528 skb->len, proto, 0); 529 } 530 531 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store 532 * Equivalent to : flow->v4addrs.src = iph->saddr; 533 * flow->v4addrs.dst = iph->daddr; 534 */ 535 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow, 536 const struct iphdr *iph) 537 { 538 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) != 539 offsetof(typeof(flow->addrs), v4addrs.src) + 540 sizeof(flow->addrs.v4addrs.src)); 541 memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs)); 542 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; 543 } 544 545 static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto) 546 { 547 const struct iphdr *iph = skb_gro_network_header(skb); 548 549 return csum_tcpudp_nofold(iph->saddr, iph->daddr, 550 skb_gro_len(skb), proto, 0); 551 } 552 553 /* 554 * Map a multicast IP onto multicast MAC for type ethernet. 555 */ 556 557 static inline void ip_eth_mc_map(__be32 naddr, char *buf) 558 { 559 __u32 addr=ntohl(naddr); 560 buf[0]=0x01; 561 buf[1]=0x00; 562 buf[2]=0x5e; 563 buf[5]=addr&0xFF; 564 addr>>=8; 565 buf[4]=addr&0xFF; 566 addr>>=8; 567 buf[3]=addr&0x7F; 568 } 569 570 /* 571 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand. 572 * Leave P_Key as 0 to be filled in by driver. 573 */ 574 575 static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) 576 { 577 __u32 addr; 578 unsigned char scope = broadcast[5] & 0xF; 579 580 buf[0] = 0; /* Reserved */ 581 buf[1] = 0xff; /* Multicast QPN */ 582 buf[2] = 0xff; 583 buf[3] = 0xff; 584 addr = ntohl(naddr); 585 buf[4] = 0xff; 586 buf[5] = 0x10 | scope; /* scope from broadcast address */ 587 buf[6] = 0x40; /* IPv4 signature */ 588 buf[7] = 0x1b; 589 buf[8] = broadcast[8]; /* P_Key */ 590 buf[9] = broadcast[9]; 591 buf[10] = 0; 592 buf[11] = 0; 593 buf[12] = 0; 594 buf[13] = 0; 595 buf[14] = 0; 596 buf[15] = 0; 597 buf[19] = addr & 0xff; 598 addr >>= 8; 599 buf[18] = addr & 0xff; 600 addr >>= 8; 601 buf[17] = addr & 0xff; 602 addr >>= 8; 603 buf[16] = addr & 0x0f; 604 } 605 606 static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) 607 { 608 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0) 609 memcpy(buf, broadcast, 4); 610 else 611 memcpy(buf, &naddr, sizeof(naddr)); 612 } 613 614 #if IS_ENABLED(CONFIG_IPV6) 615 #include <linux/ipv6.h> 616 #endif 617 618 static __inline__ void inet_reset_saddr(struct sock *sk) 619 { 620 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0; 621 #if IS_ENABLED(CONFIG_IPV6) 622 if (sk->sk_family == PF_INET6) { 623 struct ipv6_pinfo *np = inet6_sk(sk); 624 625 memset(&np->saddr, 0, sizeof(np->saddr)); 626 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr)); 627 } 628 #endif 629 } 630 631 #endif 632 633 static inline unsigned int ipv4_addr_hash(__be32 ip) 634 { 635 return (__force unsigned int) ip; 636 } 637 638 static inline u32 ipv4_portaddr_hash(const struct net *net, 639 __be32 saddr, 640 unsigned int port) 641 { 642 return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port; 643 } 644 645 bool ip_call_ra_chain(struct sk_buff *skb); 646 647 /* 648 * Functions provided by ip_fragment.c 649 */ 650 651 enum ip_defrag_users { 652 IP_DEFRAG_LOCAL_DELIVER, 653 IP_DEFRAG_CALL_RA_CHAIN, 654 IP_DEFRAG_CONNTRACK_IN, 655 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX, 656 IP_DEFRAG_CONNTRACK_OUT, 657 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX, 658 IP_DEFRAG_CONNTRACK_BRIDGE_IN, 659 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX, 660 IP_DEFRAG_VS_IN, 661 IP_DEFRAG_VS_OUT, 662 IP_DEFRAG_VS_FWD, 663 IP_DEFRAG_AF_PACKET, 664 IP_DEFRAG_MACVLAN, 665 }; 666 667 /* Return true if the value of 'user' is between 'lower_bond' 668 * and 'upper_bond' inclusively. 669 */ 670 static inline bool ip_defrag_user_in_between(u32 user, 671 enum ip_defrag_users lower_bond, 672 enum ip_defrag_users upper_bond) 673 { 674 return user >= lower_bond && user <= upper_bond; 675 } 676 677 int ip_defrag(struct net *net, struct sk_buff *skb, u32 user); 678 #ifdef CONFIG_INET 679 struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user); 680 #else 681 static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user) 682 { 683 return skb; 684 } 685 #endif 686 687 /* 688 * Functions provided by ip_forward.c 689 */ 690 691 int ip_forward(struct sk_buff *skb); 692 693 /* 694 * Functions provided by ip_options.c 695 */ 696 697 void ip_options_build(struct sk_buff *skb, struct ip_options *opt, 698 __be32 daddr, struct rtable *rt, int is_frag); 699 700 int __ip_options_echo(struct net *net, struct ip_options *dopt, 701 struct sk_buff *skb, const struct ip_options *sopt); 702 static inline int ip_options_echo(struct net *net, struct ip_options *dopt, 703 struct sk_buff *skb) 704 { 705 return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt); 706 } 707 708 void ip_options_fragment(struct sk_buff *skb); 709 int __ip_options_compile(struct net *net, struct ip_options *opt, 710 struct sk_buff *skb, __be32 *info); 711 int ip_options_compile(struct net *net, struct ip_options *opt, 712 struct sk_buff *skb); 713 int ip_options_get(struct net *net, struct ip_options_rcu **optp, 714 unsigned char *data, int optlen); 715 int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp, 716 unsigned char __user *data, int optlen); 717 void ip_options_undo(struct ip_options *opt); 718 void ip_forward_options(struct sk_buff *skb); 719 int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev); 720 721 /* 722 * Functions provided by ip_sockglue.c 723 */ 724 725 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb); 726 void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk, 727 struct sk_buff *skb, int tlen, int offset); 728 int ip_cmsg_send(struct sock *sk, struct msghdr *msg, 729 struct ipcm_cookie *ipc, bool allow_ipv6); 730 int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, 731 unsigned int optlen); 732 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, 733 int __user *optlen); 734 int compat_ip_setsockopt(struct sock *sk, int level, int optname, 735 char __user *optval, unsigned int optlen); 736 int compat_ip_getsockopt(struct sock *sk, int level, int optname, 737 char __user *optval, int __user *optlen); 738 int ip_ra_control(struct sock *sk, unsigned char on, 739 void (*destructor)(struct sock *)); 740 741 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len); 742 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, 743 u32 info, u8 *payload); 744 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport, 745 u32 info); 746 747 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb) 748 { 749 ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0); 750 } 751 752 bool icmp_global_allow(void); 753 extern int sysctl_icmp_msgs_per_sec; 754 extern int sysctl_icmp_msgs_burst; 755 756 #ifdef CONFIG_PROC_FS 757 int ip_misc_proc_init(void); 758 #endif 759 760 int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family, 761 struct netlink_ext_ack *extack); 762 763 static inline bool inetdev_valid_mtu(unsigned int mtu) 764 { 765 return likely(mtu >= IPV4_MIN_MTU); 766 } 767 768 void ip_sock_set_freebind(struct sock *sk); 769 int ip_sock_set_mtu_discover(struct sock *sk, int val); 770 void ip_sock_set_pktinfo(struct sock *sk); 771 void ip_sock_set_recverr(struct sock *sk); 772 void ip_sock_set_tos(struct sock *sk, int val); 773 774 #endif /* _IP_H */ 775