Linux 4.8.3
[linux/fpc-iii.git] / include / net / ip.h
blob9742b92dc93386ea1e8cc86911feecd0f650fa9e
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.
6 * Definitions for the IP module.
8 * Version: @(#)ip.h 1.0.2 05/07/93
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Alan Cox, <gw4pts@gw4pts.ampr.org>
14 * Changes:
15 * Mike McLagan : Routing by source
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.
22 #ifndef _IP_H
23 #define _IP_H
25 #include <linux/types.h>
26 #include <linux/ip.h>
27 #include <linux/in.h>
28 #include <linux/skbuff.h>
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>
36 struct sock;
38 struct inet_skb_parm {
39 int iif;
40 struct ip_options opt; /* Compiled IP options */
41 unsigned char flags;
43 #define IPSKB_FORWARDED BIT(0)
44 #define IPSKB_XFRM_TUNNEL_SIZE BIT(1)
45 #define IPSKB_XFRM_TRANSFORMED BIT(2)
46 #define IPSKB_FRAG_COMPLETE BIT(3)
47 #define IPSKB_REROUTED BIT(4)
48 #define IPSKB_DOREDIRECT BIT(5)
49 #define IPSKB_FRAG_PMTU BIT(6)
50 #define IPSKB_FRAG_SEGS BIT(7)
52 u16 frag_max_size;
55 static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
57 return ip_hdr(skb)->ihl * 4;
60 struct ipcm_cookie {
61 struct sockcm_cookie sockc;
62 __be32 addr;
63 int oif;
64 struct ip_options_rcu *opt;
65 __u8 tx_flags;
66 __u8 ttl;
67 __s16 tos;
68 char priority;
71 #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
72 #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
74 struct ip_ra_chain {
75 struct ip_ra_chain __rcu *next;
76 struct sock *sk;
77 union {
78 void (*destructor)(struct sock *);
79 struct sock *saved_sk;
81 struct rcu_head rcu;
84 extern struct ip_ra_chain __rcu *ip_ra_chain;
86 /* IP flags. */
87 #define IP_CE 0x8000 /* Flag: "Congestion" */
88 #define IP_DF 0x4000 /* Flag: "Don't Fragment" */
89 #define IP_MF 0x2000 /* Flag: "More Fragments" */
90 #define IP_OFFSET 0x1FFF /* "Fragment Offset" part */
92 #define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */
94 struct msghdr;
95 struct net_device;
96 struct packet_type;
97 struct rtable;
98 struct sockaddr;
100 int igmp_mc_init(void);
103 * Functions provided by ip.c
106 int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
107 __be32 saddr, __be32 daddr,
108 struct ip_options_rcu *opt);
109 int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
110 struct net_device *orig_dev);
111 int ip_local_deliver(struct sk_buff *skb);
112 int ip_mr_input(struct sk_buff *skb);
113 int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb);
114 int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb);
115 int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
116 int (*output)(struct net *, struct sock *, struct sk_buff *));
117 void ip_send_check(struct iphdr *ip);
118 int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
119 int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
121 int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
122 void ip_init(void);
123 int ip_append_data(struct sock *sk, struct flowi4 *fl4,
124 int getfrag(void *from, char *to, int offset, int len,
125 int odd, struct sk_buff *skb),
126 void *from, int len, int protolen,
127 struct ipcm_cookie *ipc,
128 struct rtable **rt,
129 unsigned int flags);
130 int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
131 struct sk_buff *skb);
132 ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
133 int offset, size_t size, int flags);
134 struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
135 struct sk_buff_head *queue,
136 struct inet_cork *cork);
137 int ip_send_skb(struct net *net, struct sk_buff *skb);
138 int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
139 void ip_flush_pending_frames(struct sock *sk);
140 struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4,
141 int getfrag(void *from, char *to, int offset,
142 int len, int odd, struct sk_buff *skb),
143 void *from, int length, int transhdrlen,
144 struct ipcm_cookie *ipc, struct rtable **rtp,
145 unsigned int flags);
147 static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
149 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
152 static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
154 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
157 static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
159 return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
162 /* datagram.c */
163 int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
164 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
166 void ip4_datagram_release_cb(struct sock *sk);
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;
178 #define IP_REPLY_ARG_NOSRCCHECK 1
180 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
182 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
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);
191 #define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field)
192 #define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((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(net, field, val) __SNMP_ADD_STATS64((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(net, field, val) __SNMP_UPD_PO_STATS64((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(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field)
199 #define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
200 #define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
202 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct);
203 unsigned long snmp_fold_field(void __percpu *mib, int offt);
204 #if BITS_PER_LONG==32
205 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
206 size_t syncp_offset);
207 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
208 #else
209 static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
210 size_t syncp_offset)
212 return snmp_get_cpu_field(mib, cpu, offct);
216 static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
218 return snmp_fold_field(mib, offt);
220 #endif
222 void inet_get_local_port_range(struct net *net, int *low, int *high);
224 #ifdef CONFIG_SYSCTL
225 static inline int inet_is_local_reserved_port(struct net *net, int port)
227 if (!net->ipv4.sysctl_local_reserved_ports)
228 return 0;
229 return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
232 static inline bool sysctl_dev_name_is_allowed(const char *name)
234 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0;
237 #else
238 static inline int inet_is_local_reserved_port(struct net *net, int port)
240 return 0;
242 #endif
244 __be32 inet_current_timestamp(void);
246 /* From inetpeer.c */
247 extern int inet_peer_threshold;
248 extern int inet_peer_minttl;
249 extern int inet_peer_maxttl;
251 void ipfrag_init(void);
253 void ip_static_sysctl_init(void);
255 #define IP4_REPLY_MARK(net, mark) \
256 ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0)
258 static inline bool ip_is_fragment(const struct iphdr *iph)
260 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
263 #ifdef CONFIG_INET
264 #include <net/dst.h>
266 /* The function in 2.2 was invalid, producing wrong result for
267 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
268 static inline
269 int ip_decrease_ttl(struct iphdr *iph)
271 u32 check = (__force u32)iph->check;
272 check += (__force u32)htons(0x0100);
273 iph->check = (__force __sum16)(check + (check>=0xFFFF));
274 return --iph->ttl;
277 static inline
278 int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
280 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
282 return pmtudisc == IP_PMTUDISC_DO ||
283 (pmtudisc == IP_PMTUDISC_WANT &&
284 !(dst_metric_locked(dst, RTAX_MTU)));
287 static inline bool ip_sk_accept_pmtu(const struct sock *sk)
289 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
290 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
293 static inline bool ip_sk_use_pmtu(const struct sock *sk)
295 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
298 static inline bool ip_sk_ignore_df(const struct sock *sk)
300 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
301 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
304 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
305 bool forwarding)
307 struct net *net = dev_net(dst->dev);
309 if (net->ipv4.sysctl_ip_fwd_use_pmtu ||
310 dst_metric_locked(dst, RTAX_MTU) ||
311 !forwarding)
312 return dst_mtu(dst);
314 return min(dst->dev->mtu, IP_MAX_MTU);
317 static inline unsigned int ip_skb_dst_mtu(struct sock *sk,
318 const struct sk_buff *skb)
320 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
321 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
323 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
326 return min(skb_dst(skb)->dev->mtu, IP_MAX_MTU);
329 u32 ip_idents_reserve(u32 hash, int segs);
330 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
332 static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
333 struct sock *sk, int segs)
335 struct iphdr *iph = ip_hdr(skb);
337 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
338 /* This is only to work around buggy Windows95/2000
339 * VJ compression implementations. If the ID field
340 * does not change, they drop every other packet in
341 * a TCP stream using header compression.
343 if (sk && inet_sk(sk)->inet_daddr) {
344 iph->id = htons(inet_sk(sk)->inet_id);
345 inet_sk(sk)->inet_id += segs;
346 } else {
347 iph->id = 0;
349 } else {
350 __ip_select_ident(net, iph, segs);
354 static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
355 struct sock *sk)
357 ip_select_ident_segs(net, skb, sk, 1);
360 static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
362 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
363 skb->len, proto, 0);
366 /* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
367 * Equivalent to : flow->v4addrs.src = iph->saddr;
368 * flow->v4addrs.dst = iph->daddr;
370 static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
371 const struct iphdr *iph)
373 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
374 offsetof(typeof(flow->addrs), v4addrs.src) +
375 sizeof(flow->addrs.v4addrs.src));
376 memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs));
377 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
380 static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto)
382 const struct iphdr *iph = skb_gro_network_header(skb);
384 return csum_tcpudp_nofold(iph->saddr, iph->daddr,
385 skb_gro_len(skb), proto, 0);
389 * Map a multicast IP onto multicast MAC for type ethernet.
392 static inline void ip_eth_mc_map(__be32 naddr, char *buf)
394 __u32 addr=ntohl(naddr);
395 buf[0]=0x01;
396 buf[1]=0x00;
397 buf[2]=0x5e;
398 buf[5]=addr&0xFF;
399 addr>>=8;
400 buf[4]=addr&0xFF;
401 addr>>=8;
402 buf[3]=addr&0x7F;
406 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
407 * Leave P_Key as 0 to be filled in by driver.
410 static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
412 __u32 addr;
413 unsigned char scope = broadcast[5] & 0xF;
415 buf[0] = 0; /* Reserved */
416 buf[1] = 0xff; /* Multicast QPN */
417 buf[2] = 0xff;
418 buf[3] = 0xff;
419 addr = ntohl(naddr);
420 buf[4] = 0xff;
421 buf[5] = 0x10 | scope; /* scope from broadcast address */
422 buf[6] = 0x40; /* IPv4 signature */
423 buf[7] = 0x1b;
424 buf[8] = broadcast[8]; /* P_Key */
425 buf[9] = broadcast[9];
426 buf[10] = 0;
427 buf[11] = 0;
428 buf[12] = 0;
429 buf[13] = 0;
430 buf[14] = 0;
431 buf[15] = 0;
432 buf[19] = addr & 0xff;
433 addr >>= 8;
434 buf[18] = addr & 0xff;
435 addr >>= 8;
436 buf[17] = addr & 0xff;
437 addr >>= 8;
438 buf[16] = addr & 0x0f;
441 static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
443 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0)
444 memcpy(buf, broadcast, 4);
445 else
446 memcpy(buf, &naddr, sizeof(naddr));
449 #if IS_ENABLED(CONFIG_IPV6)
450 #include <linux/ipv6.h>
451 #endif
453 static __inline__ void inet_reset_saddr(struct sock *sk)
455 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
456 #if IS_ENABLED(CONFIG_IPV6)
457 if (sk->sk_family == PF_INET6) {
458 struct ipv6_pinfo *np = inet6_sk(sk);
460 memset(&np->saddr, 0, sizeof(np->saddr));
461 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
463 #endif
466 #endif
468 static inline unsigned int ipv4_addr_hash(__be32 ip)
470 return (__force unsigned int) ip;
473 bool ip_call_ra_chain(struct sk_buff *skb);
476 * Functions provided by ip_fragment.c
479 enum ip_defrag_users {
480 IP_DEFRAG_LOCAL_DELIVER,
481 IP_DEFRAG_CALL_RA_CHAIN,
482 IP_DEFRAG_CONNTRACK_IN,
483 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
484 IP_DEFRAG_CONNTRACK_OUT,
485 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
486 IP_DEFRAG_CONNTRACK_BRIDGE_IN,
487 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
488 IP_DEFRAG_VS_IN,
489 IP_DEFRAG_VS_OUT,
490 IP_DEFRAG_VS_FWD,
491 IP_DEFRAG_AF_PACKET,
492 IP_DEFRAG_MACVLAN,
495 /* Return true if the value of 'user' is between 'lower_bond'
496 * and 'upper_bond' inclusively.
498 static inline bool ip_defrag_user_in_between(u32 user,
499 enum ip_defrag_users lower_bond,
500 enum ip_defrag_users upper_bond)
502 return user >= lower_bond && user <= upper_bond;
505 int ip_defrag(struct net *net, struct sk_buff *skb, u32 user);
506 #ifdef CONFIG_INET
507 struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user);
508 #else
509 static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
511 return skb;
513 #endif
514 int ip_frag_mem(struct net *net);
517 * Functions provided by ip_forward.c
520 int ip_forward(struct sk_buff *skb);
523 * Functions provided by ip_options.c
526 void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
527 __be32 daddr, struct rtable *rt, int is_frag);
529 int __ip_options_echo(struct ip_options *dopt, struct sk_buff *skb,
530 const struct ip_options *sopt);
531 static inline int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb)
533 return __ip_options_echo(dopt, skb, &IPCB(skb)->opt);
536 void ip_options_fragment(struct sk_buff *skb);
537 int ip_options_compile(struct net *net, struct ip_options *opt,
538 struct sk_buff *skb);
539 int ip_options_get(struct net *net, struct ip_options_rcu **optp,
540 unsigned char *data, int optlen);
541 int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp,
542 unsigned char __user *data, int optlen);
543 void ip_options_undo(struct ip_options *opt);
544 void ip_forward_options(struct sk_buff *skb);
545 int ip_options_rcv_srr(struct sk_buff *skb);
548 * Functions provided by ip_sockglue.c
551 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
552 void ip_cmsg_recv_offset(struct msghdr *msg, struct sk_buff *skb, int offset);
553 int ip_cmsg_send(struct sock *sk, struct msghdr *msg,
554 struct ipcm_cookie *ipc, bool allow_ipv6);
555 int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
556 unsigned int optlen);
557 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
558 int __user *optlen);
559 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
560 char __user *optval, unsigned int optlen);
561 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
562 char __user *optval, int __user *optlen);
563 int ip_ra_control(struct sock *sk, unsigned char on,
564 void (*destructor)(struct sock *));
566 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
567 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
568 u32 info, u8 *payload);
569 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
570 u32 info);
572 static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
574 ip_cmsg_recv_offset(msg, skb, 0);
577 bool icmp_global_allow(void);
578 extern int sysctl_icmp_msgs_per_sec;
579 extern int sysctl_icmp_msgs_burst;
581 #ifdef CONFIG_PROC_FS
582 int ip_misc_proc_init(void);
583 #endif
585 #endif /* _IP_H */