include/net/ip.h

   1 /*
   2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3  *              operating system.  INET is implemented using the  BSD Socket
   4  *              interface as the means of communication with the user level.
   5  *
   6  *              Definitions for the IP module.
   7  *
   8  * Version:     @(#)ip.h        1.0.2   05/07/93
   9  *
  10  * Authors:     Ross Biro
  11  *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12  *              Alan Cox, <gw4pts@gw4pts.ampr.org>
  13  *
  14  * Changes:
  15  *              Mike McLagan    :       Routing by source
  16  *
  17  *              This program is free software; you can redistribute it and/or
  18  *              modify it under the terms of the GNU General Public License
  19  *              as published by the Free Software Foundation; either version
  20  *              2 of the License, or (at your option) any later version.
  21  */
  22 #ifndef _IP_H
  23 #define _IP_H
  24
  25 #include <linux/types.h>
  26 #include <linux/ip.h>
  27 #include <linux/in.h>
  28 #include <linux/skbuff.h>
  29
  30 #include <net/inet_sock.h>
  31 #include <net/route.h>
  32 #include <net/snmp.h>
  33 #include <net/flow.h>
  34 #include <net/flow_dissector.h>
  35
  36 struct sock;
  37
  38 struct inet_skb_parm {
  39         struct ip_options       opt;            /* Compiled IP options          */
  40         unsigned char           flags;
  41
  42 #define IPSKB_FORWARDED         BIT(0)
  43 #define IPSKB_XFRM_TUNNEL_SIZE  BIT(1)
  44 #define IPSKB_XFRM_TRANSFORMED  BIT(2)
  45 #define IPSKB_FRAG_COMPLETE     BIT(3)
  46 #define IPSKB_REROUTED          BIT(4)
  47 #define IPSKB_DOREDIRECT        BIT(5)
  48 #define IPSKB_FRAG_PMTU         BIT(6)
  49
  50         u16                     frag_max_size;
  51 };
  52
  53 static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
  54 {
  55         return ip_hdr(skb)->ihl * 4;
  56 }
  57
  58 struct ipcm_cookie {
  59         __be32                  addr;
  60         int                     oif;
  61         struct ip_options_rcu   *opt;
  62         __u8                    tx_flags;
  63         __u8                    ttl;
  64         __s16                   tos;
  65         char                    priority;
  66 };
  67
  68 #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
  69 #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
  70
  71 struct ip_ra_chain {
  72         struct ip_ra_chain __rcu *next;
  73         struct sock             *sk;
  74         union {
  75                 void                    (*destructor)(struct sock *);
  76                 struct sock             *saved_sk;
  77         };
  78         struct rcu_head         rcu;
  79 };
  80
  81 extern struct ip_ra_chain __rcu *ip_ra_chain;
  82
  83 /* IP flags. */
  84 #define IP_CE           0x8000          /* Flag: "Congestion"           */
  85 #define IP_DF           0x4000          /* Flag: "Don't Fragment"       */
  86 #define IP_MF           0x2000          /* Flag: "More Fragments"       */
  87 #define IP_OFFSET       0x1FFF          /* "Fragment Offset" part       */
  88
  89 #define IP_FRAG_TIME    (30 * HZ)               /* fragment lifetime    */
  90
  91 struct msghdr;
  92 struct net_device;
  93 struct packet_type;
  94 struct rtable;
  95 struct sockaddr;
  96
  97 int igmp_mc_init(void);
  98
  99 /*
 100  *      Functions provided by ip.c
 101  */
 102
 103 int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk,
 104                           __be32 saddr, __be32 daddr,
 105                           struct ip_options_rcu *opt);
 106 int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
 107            struct net_device *orig_dev);
 108 int ip_local_deliver(struct sk_buff *skb);
 109 int ip_mr_input(struct sk_buff *skb);
 110 int ip_output(struct sock *sk, struct sk_buff *skb);
 111 int ip_mc_output(struct sock *sk, struct sk_buff *skb);
 112 int ip_do_fragment(struct sock *sk, struct sk_buff *skb,
 113                    int (*output)(struct sock *, struct sk_buff *));
 114 void ip_send_check(struct iphdr *ip);
 115 int __ip_local_out(struct sk_buff *skb);
 116 int ip_local_out_sk(struct sock *sk, struct sk_buff *skb);
 117 static inline int ip_local_out(struct sk_buff *skb)
 118 {
 119         return ip_local_out_sk(skb->sk, skb);
 120 }
 121
 122 int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
 123 void ip_init(void);
 124 int ip_append_data(struct sock *sk, struct flowi4 *fl4,
 125                    int getfrag(void *from, char *to, int offset, int len,
 126                                int odd, struct sk_buff *skb),
 127                    void *from, int len, int protolen,
 128                    struct ipcm_cookie *ipc,
 129                    struct rtable **rt,
 130                    unsigned int flags);
 131 int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
 132                        struct sk_buff *skb);
 133 ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
 134                        int offset, size_t size, int flags);
 135 struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
 136                               struct sk_buff_head *queue,
 137                               struct inet_cork *cork);
 138 int ip_send_skb(struct net *net, struct sk_buff *skb);
 139 int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
 140 void ip_flush_pending_frames(struct sock *sk);
 141 struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4,
 142                             int getfrag(void *from, char *to, int offset,
 143                                         int len, int odd, struct sk_buff *skb),
 144                             void *from, int length, int transhdrlen,
 145                             struct ipcm_cookie *ipc, struct rtable **rtp,
 146                             unsigned int flags);
 147
 148 static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
 149 {
 150         return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
 151 }
 152
 153 static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
 154 {
 155         return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
 156 }
 157
 158 static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
 159 {
 160         return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
 161 }
 162
 163 /* datagram.c */
 164 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
 165
 166 void ip4_datagram_release_cb(struct sock *sk);
 167
 168 struct ip_reply_arg {
 169         struct kvec iov[1];
 170         int         flags;
 171         __wsum      csum;
 172         int         csumoffset; /* u16 offset of csum in iov[0].iov_base */
 173                                 /* -1 if not needed */
 174         int         bound_dev_if;
 175         u8          tos;
 176 };
 177
 178 #define IP_REPLY_ARG_NOSRCCHECK 1
 179
 180 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
 181 {
 182         return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
 183 }
 184
 185 void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
 186                            const struct ip_options *sopt,
 187                            __be32 daddr, __be32 saddr,
 188                            const struct ip_reply_arg *arg,
 189                            unsigned int len);
 190
 191 #define IP_INC_STATS(net, field)        SNMP_INC_STATS64((net)->mib.ip_statistics, field)
 192 #define IP_INC_STATS_BH(net, field)     SNMP_INC_STATS64_BH((net)->mib.ip_statistics, field)
 193 #define IP_ADD_STATS(net, field, val)   SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
 194 #define IP_ADD_STATS_BH(net, field, val) SNMP_ADD_STATS64_BH((net)->mib.ip_statistics, field, val)
 195 #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
 196 #define IP_UPD_PO_STATS_BH(net, field, val) SNMP_UPD_PO_STATS64_BH((net)->mib.ip_statistics, field, val)
 197 #define NET_INC_STATS(net, field)       SNMP_INC_STATS((net)->mib.net_statistics, field)
 198 #define NET_INC_STATS_BH(net, field)    SNMP_INC_STATS_BH((net)->mib.net_statistics, field)
 199 #define NET_INC_STATS_USER(net, field)  SNMP_INC_STATS_USER((net)->mib.net_statistics, field)
 200 #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
 201 #define NET_ADD_STATS_BH(net, field, adnd) SNMP_ADD_STATS_BH((net)->mib.net_statistics, field, adnd)
 202 #define NET_ADD_STATS_USER(net, field, adnd) SNMP_ADD_STATS_USER((net)->mib.net_statistics, field, adnd)
 203
 204 unsigned long snmp_fold_field(void __percpu *mib, int offt);
 205 #if BITS_PER_LONG==32
 206 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
 207 #else
 208 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
 209 {
 210         return snmp_fold_field(mib, offt);
 211 }
 212 #endif
 213
 214 void inet_get_local_port_range(struct net *net, int *low, int *high);
 215
 216 #ifdef CONFIG_SYSCTL
 217 static inline int inet_is_local_reserved_port(struct net *net, int port)
 218 {
 219         if (!net->ipv4.sysctl_local_reserved_ports)
 220                 return 0;
 221         return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
 222 }
 223
 224 static inline bool sysctl_dev_name_is_allowed(const char *name)
 225 {
 226         return strcmp(name, "default") != 0  && strcmp(name, "all") != 0;
 227 }
 228
 229 #else
 230 static inline int inet_is_local_reserved_port(struct net *net, int port)
 231 {
 232         return 0;
 233 }
 234 #endif
 235
 236 /* From inetpeer.c */
 237 extern int inet_peer_threshold;
 238 extern int inet_peer_minttl;
 239 extern int inet_peer_maxttl;
 240
 241 /* From ip_input.c */
 242 extern int sysctl_ip_early_demux;
 243
 244 /* From ip_output.c */
 245 extern int sysctl_ip_dynaddr;
 246
 247 void ipfrag_init(void);
 248
 249 void ip_static_sysctl_init(void);
 250
 251 #define IP4_REPLY_MARK(net, mark) \
 252         ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0)
 253
 254 static inline bool ip_is_fragment(const struct iphdr *iph)
 255 {
 256         return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
 257 }
 258
 259 #ifdef CONFIG_INET
 260 #include <net/dst.h>
 261
 262 /* The function in 2.2 was invalid, producing wrong result for
 263  * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
 264 static inline
 265 int ip_decrease_ttl(struct iphdr *iph)
 266 {
 267         u32 check = (__force u32)iph->check;
 268         check += (__force u32)htons(0x0100);
 269         iph->check = (__force __sum16)(check + (check>=0xFFFF));
 270         return --iph->ttl;
 271 }
 272
 273 static inline
 274 int ip_dont_fragment(struct sock *sk, struct dst_entry *dst)
 275 {
 276         return  inet_sk(sk)->pmtudisc == IP_PMTUDISC_DO ||
 277                 (inet_sk(sk)->pmtudisc == IP_PMTUDISC_WANT &&
 278                  !(dst_metric_locked(dst, RTAX_MTU)));
 279 }
 280
 281 static inline bool ip_sk_accept_pmtu(const struct sock *sk)
 282 {
 283         return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
 284                inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
 285 }
 286
 287 static inline bool ip_sk_use_pmtu(const struct sock *sk)
 288 {
 289         return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
 290 }
 291
 292 static inline bool ip_sk_ignore_df(const struct sock *sk)
 293 {
 294         return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
 295                inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
 296 }
 297
 298 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
 299                                                     bool forwarding)
 300 {
 301         struct net *net = dev_net(dst->dev);
 302
 303         if (net->ipv4.sysctl_ip_fwd_use_pmtu ||
 304             dst_metric_locked(dst, RTAX_MTU) ||
 305             !forwarding)
 306                 return dst_mtu(dst);
 307
 308         return min(dst->dev->mtu, IP_MAX_MTU);
 309 }
 310
 311 static inline unsigned int ip_skb_dst_mtu(const struct sk_buff *skb)
 312 {
 313         if (!skb->sk || ip_sk_use_pmtu(skb->sk)) {
 314                 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
 315                 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
 316         } else {
 317                 return min(skb_dst(skb)->dev->mtu, IP_MAX_MTU);
 318         }
 319 }
 320
 321 u32 ip_idents_reserve(u32 hash, int segs);
 322 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
 323
 324 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
 325                                         struct sock *sk, int segs)
 326 {
 327         struct iphdr *iph = ip_hdr(skb);
 328
 329         if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
 330                 /* This is only to work around buggy Windows95/2000
 331                  * VJ compression implementations.  If the ID field
 332                  * does not change, they drop every other packet in
 333                  * a TCP stream using header compression.
 334                  */
 335                 if (sk && inet_sk(sk)->inet_daddr) {
 336                         iph->id = htons(inet_sk(sk)->inet_id);
 337                         inet_sk(sk)->inet_id += segs;
 338                 } else {
 339                         iph->id = 0;
 340                 }
 341         } else {
 342                 __ip_select_ident(net, iph, segs);
 343         }
 344 }
 345
 346 static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
 347                                    struct sock *sk)
 348 {
 349         ip_select_ident_segs(net, skb, sk, 1);
 350 }
 351
 352 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
 353 {
 354         return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
 355                                   skb->len, proto, 0);
 356 }
 357
 358 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
 359  * Equivalent to :      flow->v4addrs.src = iph->saddr;
 360  *                      flow->v4addrs.dst = iph->daddr;
 361  */
 362 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
 363                                             const struct iphdr *iph)
 364 {
 365         BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
 366                      offsetof(typeof(flow->addrs), v4addrs.src) +
 367                               sizeof(flow->addrs.v4addrs.src));
 368         memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs));
 369         flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
 370 }
 371
 372 static inline void inet_set_txhash(struct sock *sk)
 373 {
 374         struct inet_sock *inet = inet_sk(sk);
 375         struct flow_keys keys;
 376
 377         memset(&keys, 0, sizeof(keys));
 378
 379         keys.addrs.v4addrs.src = inet->inet_saddr;
 380         keys.addrs.v4addrs.dst = inet->inet_daddr;
 381         keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
 382         keys.ports.src = inet->inet_sport;
 383         keys.ports.dst = inet->inet_dport;
 384
 385         sk->sk_txhash = flow_hash_from_keys(&keys);
 386 }
 387
 388 static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto)
 389 {
 390         const struct iphdr *iph = skb_gro_network_header(skb);
 391
 392         return csum_tcpudp_nofold(iph->saddr, iph->daddr,
 393                                   skb_gro_len(skb), proto, 0);
 394 }
 395
 396 /*
 397  *      Map a multicast IP onto multicast MAC for type ethernet.
 398  */
 399
 400 static inline void ip_eth_mc_map(__be32 naddr, char *buf)
 401 {
 402         __u32 addr=ntohl(naddr);
 403         buf[0]=0x01;
 404         buf[1]=0x00;
 405         buf[2]=0x5e;
 406         buf[5]=addr&0xFF;
 407         addr>>=8;
 408         buf[4]=addr&0xFF;
 409         addr>>=8;
 410         buf[3]=addr&0x7F;
 411 }
 412
 413 /*
 414  *      Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
 415  *      Leave P_Key as 0 to be filled in by driver.
 416  */
 417
 418 static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
 419 {
 420         __u32 addr;
 421         unsigned char scope = broadcast[5] & 0xF;
 422
 423         buf[0]  = 0;            /* Reserved */
 424         buf[1]  = 0xff;         /* Multicast QPN */
 425         buf[2]  = 0xff;
 426         buf[3]  = 0xff;
 427         addr    = ntohl(naddr);
 428         buf[4]  = 0xff;
 429         buf[5]  = 0x10 | scope; /* scope from broadcast address */
 430         buf[6]  = 0x40;         /* IPv4 signature */
 431         buf[7]  = 0x1b;
 432         buf[8]  = broadcast[8];         /* P_Key */
 433         buf[9]  = broadcast[9];
 434         buf[10] = 0;
 435         buf[11] = 0;
 436         buf[12] = 0;
 437         buf[13] = 0;
 438         buf[14] = 0;
 439         buf[15] = 0;
 440         buf[19] = addr & 0xff;
 441         addr  >>= 8;
 442         buf[18] = addr & 0xff;
 443         addr  >>= 8;
 444         buf[17] = addr & 0xff;
 445         addr  >>= 8;
 446         buf[16] = addr & 0x0f;
 447 }
 448
 449 static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
 450 {
 451         if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0)
 452                 memcpy(buf, broadcast, 4);
 453         else
 454                 memcpy(buf, &naddr, sizeof(naddr));
 455 }
 456
 457 #if IS_ENABLED(CONFIG_IPV6)
 458 #include <linux/ipv6.h>
 459 #endif
 460
 461 static __inline__ void inet_reset_saddr(struct sock *sk)
 462 {
 463         inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
 464 #if IS_ENABLED(CONFIG_IPV6)
 465         if (sk->sk_family == PF_INET6) {
 466                 struct ipv6_pinfo *np = inet6_sk(sk);
 467
 468                 memset(&np->saddr, 0, sizeof(np->saddr));
 469                 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
 470         }
 471 #endif
 472 }
 473
 474 #endif
 475
 476 bool ip_call_ra_chain(struct sk_buff *skb);
 477
 478 /*
 479  *      Functions provided by ip_fragment.c
 480  */
 481
 482 enum ip_defrag_users {
 483         IP_DEFRAG_LOCAL_DELIVER,
 484         IP_DEFRAG_CALL_RA_CHAIN,
 485         IP_DEFRAG_CONNTRACK_IN,
 486         __IP_DEFRAG_CONNTRACK_IN_END    = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
 487         IP_DEFRAG_CONNTRACK_OUT,
 488         __IP_DEFRAG_CONNTRACK_OUT_END   = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
 489         IP_DEFRAG_CONNTRACK_BRIDGE_IN,
 490         __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
 491         IP_DEFRAG_VS_IN,
 492         IP_DEFRAG_VS_OUT,
 493         IP_DEFRAG_VS_FWD,
 494         IP_DEFRAG_AF_PACKET,
 495         IP_DEFRAG_MACVLAN,
 496 };
 497
 498 /* Return true if the value of 'user' is between 'lower_bond'
 499  * and 'upper_bond' inclusively.
 500  */
 501 static inline bool ip_defrag_user_in_between(u32 user,
 502                                              enum ip_defrag_users lower_bond,
 503                                              enum ip_defrag_users upper_bond)
 504 {
 505         return user >= lower_bond && user <= upper_bond;
 506 }
 507
 508 int ip_defrag(struct sk_buff *skb, u32 user);
 509 #ifdef CONFIG_INET
 510 struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user);
 511 #else
 512 static inline struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user)
 513 {
 514         return skb;
 515 }
 516 #endif
 517 int ip_frag_mem(struct net *net);
 518
 519 /*
 520  *      Functions provided by ip_forward.c
 521  */
 522
 523 int ip_forward(struct sk_buff *skb);
 524
 525 /*
 526  *      Functions provided by ip_options.c
 527  */
 528
 529 void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
 530                       __be32 daddr, struct rtable *rt, int is_frag);
 531
 532 int __ip_options_echo(struct ip_options *dopt, struct sk_buff *skb,
 533                       const struct ip_options *sopt);
 534 static inline int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb)
 535 {
 536         return __ip_options_echo(dopt, skb, &IPCB(skb)->opt);
 537 }
 538
 539 void ip_options_fragment(struct sk_buff *skb);
 540 int ip_options_compile(struct net *net, struct ip_options *opt,
 541                        struct sk_buff *skb);
 542 int ip_options_get(struct net *net, struct ip_options_rcu **optp,
 543                    unsigned char *data, int optlen);
 544 int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp,
 545                              unsigned char __user *data, int optlen);
 546 void ip_options_undo(struct ip_options *opt);
 547 void ip_forward_options(struct sk_buff *skb);
 548 int ip_options_rcv_srr(struct sk_buff *skb);
 549
 550 /*
 551  *      Functions provided by ip_sockglue.c
 552  */
 553
 554 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
 555 void ip_cmsg_recv_offset(struct msghdr *msg, struct sk_buff *skb, int offset);
 556 int ip_cmsg_send(struct net *net, struct msghdr *msg,
 557                  struct ipcm_cookie *ipc, bool allow_ipv6);
 558 int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
 559                   unsigned int optlen);
 560 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
 561                   int __user *optlen);
 562 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
 563                          char __user *optval, unsigned int optlen);
 564 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
 565                          char __user *optval, int __user *optlen);
 566 int ip_ra_control(struct sock *sk, unsigned char on,
 567                   void (*destructor)(struct sock *));
 568
 569 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
 570 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
 571                    u32 info, u8 *payload);
 572 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
 573                     u32 info);
 574
 575 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
 576 {
 577         ip_cmsg_recv_offset(msg, skb, 0);
 578 }
 579
 580 bool icmp_global_allow(void);
 581 extern int sysctl_icmp_msgs_per_sec;
 582 extern int sysctl_icmp_msgs_burst;
 583
 584 #ifdef CONFIG_PROC_FS
 585 int ip_misc_proc_init(void);
 586 #endif
 587
 588 #endif  /* _IP_H */