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, const 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 net *net, struct sock *sk, struct sk_buff *skb,
 113                    int (*output)(struct net *, 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 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
 166
 167 void ip4_datagram_release_cb(struct sock *sk);
 168
 169 struct ip_reply_arg {
 170         struct kvec iov[1];
 171         int         flags;
 172         __wsum      csum;
 173         int         csumoffset; /* u16 offset of csum in iov[0].iov_base */
 174                                 /* -1 if not needed */
 175         int         bound_dev_if;
 176         u8          tos;
 177 };
 178
 179 #define IP_REPLY_ARG_NOSRCCHECK 1
 180
 181 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
 182 {
 183         return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
 184 }
 185
 186 void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
 187                            const struct ip_options *sopt,
 188                            __be32 daddr, __be32 saddr,
 189                            const struct ip_reply_arg *arg,
 190                            unsigned int len);
 191
 192 #define IP_INC_STATS(net, field)        SNMP_INC_STATS64((net)->mib.ip_statistics, field)
 193 #define IP_INC_STATS_BH(net, field)     SNMP_INC_STATS64_BH((net)->mib.ip_statistics, field)
 194 #define IP_ADD_STATS(net, field, val)   SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
 195 #define IP_ADD_STATS_BH(net, field, val) SNMP_ADD_STATS64_BH((net)->mib.ip_statistics, field, val)
 196 #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
 197 #define IP_UPD_PO_STATS_BH(net, field, val) SNMP_UPD_PO_STATS64_BH((net)->mib.ip_statistics, field, val)
 198 #define NET_INC_STATS(net, field)       SNMP_INC_STATS((net)->mib.net_statistics, field)
 199 #define NET_INC_STATS_BH(net, field)    SNMP_INC_STATS_BH((net)->mib.net_statistics, field)
 200 #define NET_INC_STATS_USER(net, field)  SNMP_INC_STATS_USER((net)->mib.net_statistics, field)
 201 #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
 202 #define NET_ADD_STATS_BH(net, field, adnd) SNMP_ADD_STATS_BH((net)->mib.net_statistics, field, adnd)
 203 #define NET_ADD_STATS_USER(net, field, adnd) SNMP_ADD_STATS_USER((net)->mib.net_statistics, field, adnd)
 204
 205 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct);
 206 unsigned long snmp_fold_field(void __percpu *mib, int offt);
 207 #if BITS_PER_LONG==32
 208 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
 209                          size_t syncp_offset);
 210 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
 211 #else
 212 static inline u64  snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
 213                                         size_t syncp_offset)
 214 {
 215         return snmp_get_cpu_field(mib, cpu, offct);
 216
 217 }
 218
 219 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
 220 {
 221         return snmp_fold_field(mib, offt);
 222 }
 223 #endif
 224
 225 void inet_get_local_port_range(struct net *net, int *low, int *high);
 226
 227 #ifdef CONFIG_SYSCTL
 228 static inline int inet_is_local_reserved_port(struct net *net, int port)
 229 {
 230         if (!net->ipv4.sysctl_local_reserved_ports)
 231                 return 0;
 232         return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
 233 }
 234
 235 static inline bool sysctl_dev_name_is_allowed(const char *name)
 236 {
 237         return strcmp(name, "default") != 0  && strcmp(name, "all") != 0;
 238 }
 239
 240 #else
 241 static inline int inet_is_local_reserved_port(struct net *net, int port)
 242 {
 243         return 0;
 244 }
 245 #endif
 246
 247 /* From inetpeer.c */
 248 extern int inet_peer_threshold;
 249 extern int inet_peer_minttl;
 250 extern int inet_peer_maxttl;
 251
 252 /* From ip_input.c */
 253 extern int sysctl_ip_early_demux;
 254
 255 /* From ip_output.c */
 256 extern int sysctl_ip_dynaddr;
 257
 258 void ipfrag_init(void);
 259
 260 void ip_static_sysctl_init(void);
 261
 262 #define IP4_REPLY_MARK(net, mark) \
 263         ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0)
 264
 265 static inline bool ip_is_fragment(const struct iphdr *iph)
 266 {
 267         return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
 268 }
 269
 270 #ifdef CONFIG_INET
 271 #include <net/dst.h>
 272
 273 /* The function in 2.2 was invalid, producing wrong result for
 274  * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
 275 static inline
 276 int ip_decrease_ttl(struct iphdr *iph)
 277 {
 278         u32 check = (__force u32)iph->check;
 279         check += (__force u32)htons(0x0100);
 280         iph->check = (__force __sum16)(check + (check>=0xFFFF));
 281         return --iph->ttl;
 282 }
 283
 284 static inline
 285 int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
 286 {
 287         u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
 288
 289         return  pmtudisc == IP_PMTUDISC_DO ||
 290                 (pmtudisc == IP_PMTUDISC_WANT &&
 291                  !(dst_metric_locked(dst, RTAX_MTU)));
 292 }
 293
 294 static inline bool ip_sk_accept_pmtu(const struct sock *sk)
 295 {
 296         return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
 297                inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
 298 }
 299
 300 static inline bool ip_sk_use_pmtu(const struct sock *sk)
 301 {
 302         return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
 303 }
 304
 305 static inline bool ip_sk_ignore_df(const struct sock *sk)
 306 {
 307         return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
 308                inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
 309 }
 310
 311 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
 312                                                     bool forwarding)
 313 {
 314         struct net *net = dev_net(dst->dev);
 315
 316         if (net->ipv4.sysctl_ip_fwd_use_pmtu ||
 317             dst_metric_locked(dst, RTAX_MTU) ||
 318             !forwarding)
 319                 return dst_mtu(dst);
 320
 321         return min(dst->dev->mtu, IP_MAX_MTU);
 322 }
 323
 324 static inline unsigned int ip_skb_dst_mtu(const struct sk_buff *skb)
 325 {
 326         struct sock *sk = skb->sk;
 327
 328         if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
 329                 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
 330
 331                 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
 332         }
 333
 334         return min(skb_dst(skb)->dev->mtu, IP_MAX_MTU);
 335 }
 336
 337 u32 ip_idents_reserve(u32 hash, int segs);
 338 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
 339
 340 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
 341                                         struct sock *sk, int segs)
 342 {
 343         struct iphdr *iph = ip_hdr(skb);
 344
 345         if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
 346                 /* This is only to work around buggy Windows95/2000
 347                  * VJ compression implementations.  If the ID field
 348                  * does not change, they drop every other packet in
 349                  * a TCP stream using header compression.
 350                  */
 351                 if (sk && inet_sk(sk)->inet_daddr) {
 352                         iph->id = htons(inet_sk(sk)->inet_id);
 353                         inet_sk(sk)->inet_id += segs;
 354                 } else {
 355                         iph->id = 0;
 356                 }
 357         } else {
 358                 __ip_select_ident(net, iph, segs);
 359         }
 360 }
 361
 362 static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
 363                                    struct sock *sk)
 364 {
 365         ip_select_ident_segs(net, skb, sk, 1);
 366 }
 367
 368 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
 369 {
 370         return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
 371                                   skb->len, proto, 0);
 372 }
 373
 374 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
 375  * Equivalent to :      flow->v4addrs.src = iph->saddr;
 376  *                      flow->v4addrs.dst = iph->daddr;
 377  */
 378 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
 379                                             const struct iphdr *iph)
 380 {
 381         BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
 382                      offsetof(typeof(flow->addrs), v4addrs.src) +
 383                               sizeof(flow->addrs.v4addrs.src));
 384         memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs));
 385         flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
 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 static inline unsigned int ipv4_addr_hash(__be32 ip)
 477 {
 478         return (__force unsigned int) ip;
 479 }
 480
 481 bool ip_call_ra_chain(struct sk_buff *skb);
 482
 483 /*
 484  *      Functions provided by ip_fragment.c
 485  */
 486
 487 enum ip_defrag_users {
 488         IP_DEFRAG_LOCAL_DELIVER,
 489         IP_DEFRAG_CALL_RA_CHAIN,
 490         IP_DEFRAG_CONNTRACK_IN,
 491         __IP_DEFRAG_CONNTRACK_IN_END    = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
 492         IP_DEFRAG_CONNTRACK_OUT,
 493         __IP_DEFRAG_CONNTRACK_OUT_END   = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
 494         IP_DEFRAG_CONNTRACK_BRIDGE_IN,
 495         __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
 496         IP_DEFRAG_VS_IN,
 497         IP_DEFRAG_VS_OUT,
 498         IP_DEFRAG_VS_FWD,
 499         IP_DEFRAG_AF_PACKET,
 500         IP_DEFRAG_MACVLAN,
 501 };
 502
 503 /* Return true if the value of 'user' is between 'lower_bond'
 504  * and 'upper_bond' inclusively.
 505  */
 506 static inline bool ip_defrag_user_in_between(u32 user,
 507                                              enum ip_defrag_users lower_bond,
 508                                              enum ip_defrag_users upper_bond)
 509 {
 510         return user >= lower_bond && user <= upper_bond;
 511 }
 512
 513 int ip_defrag(struct sk_buff *skb, u32 user);
 514 #ifdef CONFIG_INET
 515 struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user);
 516 #else
 517 static inline struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user)
 518 {
 519         return skb;
 520 }
 521 #endif
 522 int ip_frag_mem(struct net *net);
 523
 524 /*
 525  *      Functions provided by ip_forward.c
 526  */
 527
 528 int ip_forward(struct sk_buff *skb);
 529
 530 /*
 531  *      Functions provided by ip_options.c
 532  */
 533
 534 void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
 535                       __be32 daddr, struct rtable *rt, int is_frag);
 536
 537 int __ip_options_echo(struct ip_options *dopt, struct sk_buff *skb,
 538                       const struct ip_options *sopt);
 539 static inline int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb)
 540 {
 541         return __ip_options_echo(dopt, skb, &IPCB(skb)->opt);
 542 }
 543
 544 void ip_options_fragment(struct sk_buff *skb);
 545 int ip_options_compile(struct net *net, struct ip_options *opt,
 546                        struct sk_buff *skb);
 547 int ip_options_get(struct net *net, struct ip_options_rcu **optp,
 548                    unsigned char *data, int optlen);
 549 int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp,
 550                              unsigned char __user *data, int optlen);
 551 void ip_options_undo(struct ip_options *opt);
 552 void ip_forward_options(struct sk_buff *skb);
 553 int ip_options_rcv_srr(struct sk_buff *skb);
 554
 555 /*
 556  *      Functions provided by ip_sockglue.c
 557  */
 558
 559 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
 560 void ip_cmsg_recv_offset(struct msghdr *msg, struct sk_buff *skb, int offset);
 561 int ip_cmsg_send(struct net *net, struct msghdr *msg,
 562                  struct ipcm_cookie *ipc, bool allow_ipv6);
 563 int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
 564                   unsigned int optlen);
 565 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
 566                   int __user *optlen);
 567 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
 568                          char __user *optval, unsigned int optlen);
 569 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
 570                          char __user *optval, int __user *optlen);
 571 int ip_ra_control(struct sock *sk, unsigned char on,
 572                   void (*destructor)(struct sock *));
 573
 574 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
 575 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
 576                    u32 info, u8 *payload);
 577 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
 578                     u32 info);
 579
 580 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
 581 {
 582         ip_cmsg_recv_offset(msg, skb, 0);
 583 }
 584
 585 bool icmp_global_allow(void);
 586 extern int sysctl_icmp_msgs_per_sec;
 587 extern int sysctl_icmp_msgs_burst;
 588
 589 #ifdef CONFIG_PROC_FS
 590 int ip_misc_proc_init(void);
 591 #endif
 592
 593 #endif  /* _IP_H */