| 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/snmp.h> |
| 32 | #include <net/flow.h> |
| 33 | |
| 34 | struct sock; |
| 35 | |
| 36 | struct inet_skb_parm |
| 37 | { |
| 38 | struct ip_options opt; /* Compiled IP options */ |
| 39 | unsigned char flags; |
| 40 | |
| 41 | #define IPSKB_FORWARDED 1 |
| 42 | #define IPSKB_XFRM_TUNNEL_SIZE 2 |
| 43 | #define IPSKB_XFRM_TRANSFORMED 4 |
| 44 | #define IPSKB_FRAG_COMPLETE 8 |
| 45 | #define IPSKB_REROUTED 16 |
| 46 | }; |
| 47 | |
| 48 | static inline unsigned int ip_hdrlen(const struct sk_buff *skb) |
| 49 | { |
| 50 | return ip_hdr(skb)->ihl * 4; |
| 51 | } |
| 52 | |
| 53 | struct ipcm_cookie |
| 54 | { |
| 55 | __be32 addr; |
| 56 | int oif; |
| 57 | struct ip_options *opt; |
| 58 | }; |
| 59 | |
| 60 | #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb)) |
| 61 | |
| 62 | struct ip_ra_chain |
| 63 | { |
| 64 | struct ip_ra_chain *next; |
| 65 | struct sock *sk; |
| 66 | void (*destructor)(struct sock *); |
| 67 | }; |
| 68 | |
| 69 | extern struct ip_ra_chain *ip_ra_chain; |
| 70 | extern rwlock_t ip_ra_lock; |
| 71 | |
| 72 | /* IP flags. */ |
| 73 | #define IP_CE 0x8000 /* Flag: "Congestion" */ |
| 74 | #define IP_DF 0x4000 /* Flag: "Don't Fragment" */ |
| 75 | #define IP_MF 0x2000 /* Flag: "More Fragments" */ |
| 76 | #define IP_OFFSET 0x1FFF /* "Fragment Offset" part */ |
| 77 | |
| 78 | #define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */ |
| 79 | |
| 80 | struct msghdr; |
| 81 | struct net_device; |
| 82 | struct packet_type; |
| 83 | struct rtable; |
| 84 | struct sockaddr; |
| 85 | |
| 86 | extern int igmp_mc_proc_init(void); |
| 87 | |
| 88 | /* |
| 89 | * Functions provided by ip.c |
| 90 | */ |
| 91 | |
| 92 | extern int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, |
| 93 | __be32 saddr, __be32 daddr, |
| 94 | struct ip_options *opt); |
| 95 | extern int ip_rcv(struct sk_buff *skb, struct net_device *dev, |
| 96 | struct packet_type *pt, struct net_device *orig_dev); |
| 97 | extern int ip_local_deliver(struct sk_buff *skb); |
| 98 | extern int ip_mr_input(struct sk_buff *skb); |
| 99 | extern int ip_output(struct sk_buff *skb); |
| 100 | extern int ip_mc_output(struct sk_buff *skb); |
| 101 | extern int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)); |
| 102 | extern int ip_do_nat(struct sk_buff *skb); |
| 103 | extern void ip_send_check(struct iphdr *ip); |
| 104 | extern int __ip_local_out(struct sk_buff *skb); |
| 105 | extern int ip_local_out(struct sk_buff *skb); |
| 106 | extern int ip_queue_xmit(struct sk_buff *skb, int ipfragok); |
| 107 | extern void ip_init(void); |
| 108 | extern int ip_append_data(struct sock *sk, |
| 109 | int getfrag(void *from, char *to, int offset, int len, |
| 110 | int odd, struct sk_buff *skb), |
| 111 | void *from, int len, int protolen, |
| 112 | struct ipcm_cookie *ipc, |
| 113 | struct rtable **rt, |
| 114 | unsigned int flags); |
| 115 | extern int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb); |
| 116 | extern ssize_t ip_append_page(struct sock *sk, struct page *page, |
| 117 | int offset, size_t size, int flags); |
| 118 | extern int ip_push_pending_frames(struct sock *sk); |
| 119 | extern void ip_flush_pending_frames(struct sock *sk); |
| 120 | |
| 121 | /* datagram.c */ |
| 122 | extern int ip4_datagram_connect(struct sock *sk, |
| 123 | struct sockaddr *uaddr, int addr_len); |
| 124 | |
| 125 | /* |
| 126 | * Map a multicast IP onto multicast MAC for type Token Ring. |
| 127 | * This conforms to RFC1469 Option 2 Multicasting i.e. |
| 128 | * using a functional address to transmit / receive |
| 129 | * multicast packets. |
| 130 | */ |
| 131 | |
| 132 | static inline void ip_tr_mc_map(__be32 addr, char *buf) |
| 133 | { |
| 134 | buf[0]=0xC0; |
| 135 | buf[1]=0x00; |
| 136 | buf[2]=0x00; |
| 137 | buf[3]=0x04; |
| 138 | buf[4]=0x00; |
| 139 | buf[5]=0x00; |
| 140 | } |
| 141 | |
| 142 | struct ip_reply_arg { |
| 143 | struct kvec iov[1]; |
| 144 | int flags; |
| 145 | __wsum csum; |
| 146 | int csumoffset; /* u16 offset of csum in iov[0].iov_base */ |
| 147 | /* -1 if not needed */ |
| 148 | int bound_dev_if; |
| 149 | }; |
| 150 | |
| 151 | #define IP_REPLY_ARG_NOSRCCHECK 1 |
| 152 | |
| 153 | static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg) |
| 154 | { |
| 155 | return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0; |
| 156 | } |
| 157 | |
| 158 | void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *arg, |
| 159 | unsigned int len); |
| 160 | |
| 161 | struct ipv4_config |
| 162 | { |
| 163 | int log_martians; |
| 164 | int no_pmtu_disc; |
| 165 | }; |
| 166 | |
| 167 | extern struct ipv4_config ipv4_config; |
| 168 | #define IP_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.ip_statistics, field) |
| 169 | #define IP_INC_STATS_BH(net, field) SNMP_INC_STATS_BH((net)->mib.ip_statistics, field) |
| 170 | #define IP_ADD_STATS_BH(net, field, val) SNMP_ADD_STATS_BH((net)->mib.ip_statistics, field, val) |
| 171 | #define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field) |
| 172 | #define NET_INC_STATS_BH(net, field) SNMP_INC_STATS_BH((net)->mib.net_statistics, field) |
| 173 | #define NET_INC_STATS_USER(net, field) SNMP_INC_STATS_USER((net)->mib.net_statistics, field) |
| 174 | #define NET_ADD_STATS_BH(net, field, adnd) SNMP_ADD_STATS_BH((net)->mib.net_statistics, field, adnd) |
| 175 | #define NET_ADD_STATS_USER(net, field, adnd) SNMP_ADD_STATS_USER((net)->mib.net_statistics, field, adnd) |
| 176 | |
| 177 | extern unsigned long snmp_fold_field(void *mib[], int offt); |
| 178 | extern int snmp_mib_init(void *ptr[2], size_t mibsize); |
| 179 | extern void snmp_mib_free(void *ptr[2]); |
| 180 | |
| 181 | extern struct local_ports { |
| 182 | seqlock_t lock; |
| 183 | int range[2]; |
| 184 | } sysctl_local_ports; |
| 185 | extern void inet_get_local_port_range(int *low, int *high); |
| 186 | |
| 187 | extern int sysctl_ip_default_ttl; |
| 188 | extern int sysctl_ip_nonlocal_bind; |
| 189 | |
| 190 | extern struct ctl_path net_ipv4_ctl_path[]; |
| 191 | |
| 192 | /* From inetpeer.c */ |
| 193 | extern int inet_peer_threshold; |
| 194 | extern int inet_peer_minttl; |
| 195 | extern int inet_peer_maxttl; |
| 196 | extern int inet_peer_gc_mintime; |
| 197 | extern int inet_peer_gc_maxtime; |
| 198 | |
| 199 | /* From ip_output.c */ |
| 200 | extern int sysctl_ip_dynaddr; |
| 201 | |
| 202 | extern void ipfrag_init(void); |
| 203 | |
| 204 | extern void ip_static_sysctl_init(void); |
| 205 | |
| 206 | #ifdef CONFIG_INET |
| 207 | #include <net/dst.h> |
| 208 | |
| 209 | /* The function in 2.2 was invalid, producing wrong result for |
| 210 | * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */ |
| 211 | static inline |
| 212 | int ip_decrease_ttl(struct iphdr *iph) |
| 213 | { |
| 214 | u32 check = (__force u32)iph->check; |
| 215 | check += (__force u32)htons(0x0100); |
| 216 | iph->check = (__force __sum16)(check + (check>=0xFFFF)); |
| 217 | return --iph->ttl; |
| 218 | } |
| 219 | |
| 220 | static inline |
| 221 | int ip_dont_fragment(struct sock *sk, struct dst_entry *dst) |
| 222 | { |
| 223 | return (inet_sk(sk)->pmtudisc == IP_PMTUDISC_DO || |
| 224 | (inet_sk(sk)->pmtudisc == IP_PMTUDISC_WANT && |
| 225 | !(dst_metric_locked(dst, RTAX_MTU)))); |
| 226 | } |
| 227 | |
| 228 | extern void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more); |
| 229 | |
| 230 | static inline void ip_select_ident(struct iphdr *iph, struct dst_entry *dst, struct sock *sk) |
| 231 | { |
| 232 | if (iph->frag_off & htons(IP_DF)) { |
| 233 | /* This is only to work around buggy Windows95/2000 |
| 234 | * VJ compression implementations. If the ID field |
| 235 | * does not change, they drop every other packet in |
| 236 | * a TCP stream using header compression. |
| 237 | */ |
| 238 | iph->id = (sk && inet_sk(sk)->daddr) ? |
| 239 | htons(inet_sk(sk)->id++) : 0; |
| 240 | } else |
| 241 | __ip_select_ident(iph, dst, 0); |
| 242 | } |
| 243 | |
| 244 | static inline void ip_select_ident_more(struct iphdr *iph, struct dst_entry *dst, struct sock *sk, int more) |
| 245 | { |
| 246 | if (iph->frag_off & htons(IP_DF)) { |
| 247 | if (sk && inet_sk(sk)->daddr) { |
| 248 | iph->id = htons(inet_sk(sk)->id); |
| 249 | inet_sk(sk)->id += 1 + more; |
| 250 | } else |
| 251 | iph->id = 0; |
| 252 | } else |
| 253 | __ip_select_ident(iph, dst, more); |
| 254 | } |
| 255 | |
| 256 | /* |
| 257 | * Map a multicast IP onto multicast MAC for type ethernet. |
| 258 | */ |
| 259 | |
| 260 | static inline void ip_eth_mc_map(__be32 naddr, char *buf) |
| 261 | { |
| 262 | __u32 addr=ntohl(naddr); |
| 263 | buf[0]=0x01; |
| 264 | buf[1]=0x00; |
| 265 | buf[2]=0x5e; |
| 266 | buf[5]=addr&0xFF; |
| 267 | addr>>=8; |
| 268 | buf[4]=addr&0xFF; |
| 269 | addr>>=8; |
| 270 | buf[3]=addr&0x7F; |
| 271 | } |
| 272 | |
| 273 | /* |
| 274 | * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand. |
| 275 | * Leave P_Key as 0 to be filled in by driver. |
| 276 | */ |
| 277 | |
| 278 | static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) |
| 279 | { |
| 280 | __u32 addr; |
| 281 | unsigned char scope = broadcast[5] & 0xF; |
| 282 | |
| 283 | buf[0] = 0; /* Reserved */ |
| 284 | buf[1] = 0xff; /* Multicast QPN */ |
| 285 | buf[2] = 0xff; |
| 286 | buf[3] = 0xff; |
| 287 | addr = ntohl(naddr); |
| 288 | buf[4] = 0xff; |
| 289 | buf[5] = 0x10 | scope; /* scope from broadcast address */ |
| 290 | buf[6] = 0x40; /* IPv4 signature */ |
| 291 | buf[7] = 0x1b; |
| 292 | buf[8] = broadcast[8]; /* P_Key */ |
| 293 | buf[9] = broadcast[9]; |
| 294 | buf[10] = 0; |
| 295 | buf[11] = 0; |
| 296 | buf[12] = 0; |
| 297 | buf[13] = 0; |
| 298 | buf[14] = 0; |
| 299 | buf[15] = 0; |
| 300 | buf[19] = addr & 0xff; |
| 301 | addr >>= 8; |
| 302 | buf[18] = addr & 0xff; |
| 303 | addr >>= 8; |
| 304 | buf[17] = addr & 0xff; |
| 305 | addr >>= 8; |
| 306 | buf[16] = addr & 0x0f; |
| 307 | } |
| 308 | |
| 309 | #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| 310 | #include <linux/ipv6.h> |
| 311 | #endif |
| 312 | |
| 313 | static __inline__ void inet_reset_saddr(struct sock *sk) |
| 314 | { |
| 315 | inet_sk(sk)->rcv_saddr = inet_sk(sk)->saddr = 0; |
| 316 | #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| 317 | if (sk->sk_family == PF_INET6) { |
| 318 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 319 | |
| 320 | memset(&np->saddr, 0, sizeof(np->saddr)); |
| 321 | memset(&np->rcv_saddr, 0, sizeof(np->rcv_saddr)); |
| 322 | } |
| 323 | #endif |
| 324 | } |
| 325 | |
| 326 | #endif |
| 327 | |
| 328 | extern int ip_call_ra_chain(struct sk_buff *skb); |
| 329 | |
| 330 | /* |
| 331 | * Functions provided by ip_fragment.c |
| 332 | */ |
| 333 | |
| 334 | enum ip_defrag_users |
| 335 | { |
| 336 | IP_DEFRAG_LOCAL_DELIVER, |
| 337 | IP_DEFRAG_CALL_RA_CHAIN, |
| 338 | IP_DEFRAG_CONNTRACK_IN, |
| 339 | IP_DEFRAG_CONNTRACK_OUT, |
| 340 | IP_DEFRAG_VS_IN, |
| 341 | IP_DEFRAG_VS_OUT, |
| 342 | IP_DEFRAG_VS_FWD |
| 343 | }; |
| 344 | |
| 345 | int ip_defrag(struct sk_buff *skb, u32 user); |
| 346 | int ip_frag_mem(struct net *net); |
| 347 | int ip_frag_nqueues(struct net *net); |
| 348 | |
| 349 | /* |
| 350 | * Functions provided by ip_forward.c |
| 351 | */ |
| 352 | |
| 353 | extern int ip_forward(struct sk_buff *skb); |
| 354 | |
| 355 | /* |
| 356 | * Functions provided by ip_options.c |
| 357 | */ |
| 358 | |
| 359 | extern void ip_options_build(struct sk_buff *skb, struct ip_options *opt, __be32 daddr, struct rtable *rt, int is_frag); |
| 360 | extern int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb); |
| 361 | extern void ip_options_fragment(struct sk_buff *skb); |
| 362 | extern int ip_options_compile(struct net *net, |
| 363 | struct ip_options *opt, struct sk_buff *skb); |
| 364 | extern int ip_options_get(struct net *net, struct ip_options **optp, |
| 365 | unsigned char *data, int optlen); |
| 366 | extern int ip_options_get_from_user(struct net *net, struct ip_options **optp, |
| 367 | unsigned char __user *data, int optlen); |
| 368 | extern void ip_options_undo(struct ip_options * opt); |
| 369 | extern void ip_forward_options(struct sk_buff *skb); |
| 370 | extern int ip_options_rcv_srr(struct sk_buff *skb); |
| 371 | |
| 372 | /* |
| 373 | * Functions provided by ip_sockglue.c |
| 374 | */ |
| 375 | |
| 376 | extern void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb); |
| 377 | extern int ip_cmsg_send(struct net *net, |
| 378 | struct msghdr *msg, struct ipcm_cookie *ipc); |
| 379 | extern int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, int optlen); |
| 380 | extern int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen); |
| 381 | extern int compat_ip_setsockopt(struct sock *sk, int level, |
| 382 | int optname, char __user *optval, int optlen); |
| 383 | extern int compat_ip_getsockopt(struct sock *sk, int level, |
| 384 | int optname, char __user *optval, int __user *optlen); |
| 385 | extern int ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *)); |
| 386 | |
| 387 | extern int ip_recv_error(struct sock *sk, struct msghdr *msg, int len); |
| 388 | extern void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, |
| 389 | __be16 port, u32 info, u8 *payload); |
| 390 | extern void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport, |
| 391 | u32 info); |
| 392 | |
| 393 | /* sysctl helpers - any sysctl which holds a value that ends up being |
| 394 | * fed into the routing cache should use these handlers. |
| 395 | */ |
| 396 | int ipv4_doint_and_flush(ctl_table *ctl, int write, |
| 397 | struct file* filp, void __user *buffer, |
| 398 | size_t *lenp, loff_t *ppos); |
| 399 | int ipv4_doint_and_flush_strategy(ctl_table *table, |
| 400 | void __user *oldval, size_t __user *oldlenp, |
| 401 | void __user *newval, size_t newlen); |
| 402 | #ifdef CONFIG_PROC_FS |
| 403 | extern int ip_misc_proc_init(void); |
| 404 | #endif |
| 405 | |
| 406 | #endif /* _IP_H */ |