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drm/amdgpu: add modifiers in amdgpu_vkms_plane_init()
[linux-2.6-block.git] / include / net / ip.h
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2874c5fd 1/* SPDX-License-Identifier: GPL-2.0-or-later */
1da177e4
LT		 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 *
02c30a84 11 * Authors: Ross Biro
1da177e4
LT		 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
1da177e4
LT		 17 */
18#ifndef _IP_H
19#define _IP_H
20
1da177e4 21#include <linux/types.h>
1da177e4
LT		 22#include <linux/ip.h>
23#include <linux/in.h>
c9bdd4b5 24#include <linux/skbuff.h>
f0b1e64c 25#include <linux/jhash.h>
de40a3e8 26#include <linux/sockptr.h>
020e71a3 27#include <linux/static_key.h>
14c85021
ACM		 28
29#include <net/inet_sock.h>
aa661581 30#include <net/route.h>
1da177e4 31#include <net/snmp.h>
86b08d86 32#include <net/flow.h>
1bd758eb 33#include <net/flow_dissector.h>
f0b1e64c 34#include <net/netns/hash.h>
fade5641 35#include <net/lwtunnel.h>
1da177e4 36
7ed14d97 37#define IPV4_MAX_PMTU 65535U /* RFC 2675, Section 5.1 */
b5476022 38#define IPV4_MIN_MTU 68 /* RFC 791 */
7ed14d97 39
9ab948a9
DA		 40extern unsigned int sysctl_fib_sync_mem;
41extern unsigned int sysctl_fib_sync_mem_min;
42extern unsigned int sysctl_fib_sync_mem_max;
43
1da177e4
LT		 44struct sock;
45
fd2c3ef7 46struct inet_skb_parm {
0b922b7a 47 int iif;
1da177e4 48 struct ip_options opt; /* Compiled IP options */
a04a480d 49 u16 flags;
1da177e4 50
df4d9254
HFS		 51#define IPSKB_FORWARDED BIT(0)
52#define IPSKB_XFRM_TUNNEL_SIZE BIT(1)
53#define IPSKB_XFRM_TRANSFORMED BIT(2)
54#define IPSKB_FRAG_COMPLETE BIT(3)
55#define IPSKB_REROUTED BIT(4)
56#define IPSKB_DOREDIRECT BIT(5)
d6b915e2 57#define IPSKB_FRAG_PMTU BIT(6)
9ee6c5dc 58#define IPSKB_L3SLAVE BIT(7)
5f2d04f1
PM		 59
60 u16 frag_max_size;
1da177e4
LT		 61};
62
a04a480d
DA		 63static inline bool ipv4_l3mdev_skb(u16 flags)
64{
65 return !!(flags & IPSKB_L3SLAVE);
66}
67
c9bdd4b5
ACM		 68static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
69{
eddc9ec5 70 return ip_hdr(skb)->ihl * 4;
c9bdd4b5
ACM		 71}
72
fd2c3ef7 73struct ipcm_cookie {
24025c46 74 struct sockcm_cookie sockc;
c1d18f9f 75 __be32 addr;
1da177e4 76 int oif;
f6d8bd05 77 struct ip_options_rcu *opt;
f02db315
FF		 78 __u8 ttl;
79 __s16 tos;
80 char priority;
bec1f6f6 81 __u16 gso_size;
1da177e4
LT		 82};
83
35178206
WB		 84static inline void ipcm_init(struct ipcm_cookie *ipcm)
85{
86 *ipcm = (struct ipcm_cookie) { .tos = -1 };
87}
88
89static inline void ipcm_init_sk(struct ipcm_cookie *ipcm,
90 const struct inet_sock *inet)
91{
92 ipcm_init(ipcm);
93
c6af0c22 94 ipcm->sockc.mark = inet->sk.sk_mark;
35178206
WB		 95 ipcm->sockc.tsflags = inet->sk.sk_tsflags;
96 ipcm->oif = inet->sk.sk_bound_dev_if;
97 ipcm->addr = inet->inet_saddr;
98}
99
1da177e4 100#define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
4b261c75 101#define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
1da177e4 102
fb74c277 103/* return enslaved device index if relevant */
d6bb2d1e 104static inline int inet_sdif(const struct sk_buff *skb)
fb74c277
DA		 105{
106#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
107 if (skb && ipv4_l3mdev_skb(IPCB(skb)->flags))
108 return IPCB(skb)->iif;
109#endif
110 return 0;
111}
112
5796ef75
KT		 113/* Special input handler for packets caught by router alert option.
114 They are selected only by protocol field, and then processed likely
115 local ones; but only if someone wants them! Otherwise, router
116 not running rsvpd will kill RSVP.
117
118 It is user level problem, what it will make with them.
119 I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
120 but receiver should be enough clever f.e. to forward mtrace requests,
121 sent to multicast group to reach destination designated router.
122 */
123
fd2c3ef7 124struct ip_ra_chain {
43a951e9 125 struct ip_ra_chain __rcu *next;
1da177e4 126 struct sock *sk;
592fcb9d
ED		 127 union {
128 void (*destructor)(struct sock *);
129 struct sock *saved_sk;
130 };
66018506 131 struct rcu_head rcu;
1da177e4
LT		 132};
133
1da177e4
LT		 134/* IP flags. */
135#define IP_CE 0x8000 /* Flag: "Congestion" */
136#define IP_DF 0x4000 /* Flag: "Don't Fragment" */
137#define IP_MF 0x2000 /* Flag: "More Fragments" */
138#define IP_OFFSET 0x1FFF /* "Fragment Offset" part */
139
140#define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */
141
14c85021
ACM		 142struct msghdr;
143struct net_device;
144struct packet_type;
145struct rtable;
14c85021
ACM		 146struct sockaddr;
147
72c1d3bd 148int igmp_mc_init(void);
1da177e4
LT		 149
150/*
151 * Functions provided by ip.c
152 */
153
cfe673b0 154int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
5c3a0fd7 155 __be32 saddr, __be32 daddr,
de033b7d 156 struct ip_options_rcu *opt, u8 tos);
5c3a0fd7
JP		 157int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
158 struct net_device *orig_dev);
17266ee9
EC		 159void ip_list_rcv(struct list_head *head, struct packet_type *pt,
160 struct net_device *orig_dev);
5c3a0fd7 161int ip_local_deliver(struct sk_buff *skb);
68cb7d53 162void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int proto);
5c3a0fd7 163int ip_mr_input(struct sk_buff *skb);
ede2059d
EB		 164int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb);
165int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb);
694869b3
EB		 166int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
167 int (*output)(struct net *, struct sock *, struct sk_buff *));
c8b17be0
PNA		 168
169struct ip_fraglist_iter {
c8b17be0
PNA		 170 struct sk_buff *frag;
171 struct iphdr *iph;
172 int offset;
173 unsigned int hlen;
174};
175
176void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph,
177 unsigned int hlen, struct ip_fraglist_iter *iter);
178void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter);
179
180static inline struct sk_buff *ip_fraglist_next(struct ip_fraglist_iter *iter)
181{
182 struct sk_buff *skb = iter->frag;
183
184 iter->frag = skb->next;
185 skb_mark_not_on_list(skb);
186
187 return skb;
188}
189
065ff79f 190struct ip_frag_state {
e7a409c3 191 bool DF;
065ff79f
PNA		 192 unsigned int hlen;
193 unsigned int ll_rs;
194 unsigned int mtu;
195 unsigned int left;
196 int offset;
197 int ptr;
198 __be16 not_last_frag;
199};
200
201void ip_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int ll_rs,
e7a409c3 202 unsigned int mtu, bool DF, struct ip_frag_state *state);
065ff79f
PNA		 203struct sk_buff *ip_frag_next(struct sk_buff *skb,
204 struct ip_frag_state *state);
205
5c3a0fd7 206void ip_send_check(struct iphdr *ip);
cf91a99d 207int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
33224b16 208int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
aad88724 209
69b9e1e0
XL		 210int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
211 __u8 tos);
5c3a0fd7
JP		 212void ip_init(void);
213int ip_append_data(struct sock *sk, struct flowi4 *fl4,
214 int getfrag(void *from, char *to, int offset, int len,
215 int odd, struct sk_buff *skb),
216 void *from, int len, int protolen,
217 struct ipcm_cookie *ipc,
218 struct rtable **rt,
219 unsigned int flags);
220int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
221 struct sk_buff *skb);
222ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
223 int offset, size_t size, int flags);
224struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
225 struct sk_buff_head *queue,
226 struct inet_cork *cork);
227int ip_send_skb(struct net *net, struct sk_buff *skb);
228int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
229void ip_flush_pending_frames(struct sock *sk);
230struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4,
231 int getfrag(void *from, char *to, int offset,
232 int len, int odd, struct sk_buff *skb),
233 void *from, int length, int transhdrlen,
234 struct ipcm_cookie *ipc, struct rtable **rtp,
1cd7884d 235 struct inet_cork *cork, unsigned int flags);
1c32c5ad 236
05e22e83 237int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
69b9e1e0 238
77968b78 239static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
1c32c5ad 240{
77968b78 241 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
1c32c5ad 242}
1da177e4 243
aa661581
FF		 244static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
245{
246 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
247}
248
249static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
250{
251 return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
252}
253
1da177e4 254/* datagram.c */
03645a11 255int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
5c3a0fd7 256int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
1da177e4 257
5c3a0fd7 258void ip4_datagram_release_cb(struct sock *sk);
8141ed9f 259
1da177e4 260struct ip_reply_arg {
82695b30 261 struct kvec iov[1];
88ef4a5a 262 int flags;
d6f5493c 263 __wsum csum;
1da177e4 264 int csumoffset; /* u16 offset of csum in iov[0].iov_base */
82695b30 265 /* -1 if not needed */
f0e48dbf 266 int bound_dev_if;
66b13d99 267 u8 tos;
e2d118a1 268 kuid_t uid;
82695b30 269};
1da177e4 270
88ef4a5a
KK		 271#define IP_REPLY_ARG_NOSRCCHECK 1
272
86b08d86
KK		 273static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
274{
275 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
276}
277
bdbbb852 278void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
24a2d43d
ED		 279 const struct ip_options *sopt,
280 __be32 daddr, __be32 saddr,
281 const struct ip_reply_arg *arg,
d6fb396c 282 unsigned int len, u64 transmit_time);
1da177e4 283
4ce3c183 284#define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field)
13415e46 285#define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field)
4ce3c183 286#define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
13415e46 287#define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
4ce3c183 288#define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
13415e46 289#define __IP_UPD_PO_STATS(net, field, val) __SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
61a7e260 290#define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field)
13415e46 291#define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field)
f7324acd 292#define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
13415e46 293#define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
1da177e4 294
59f09ae8
ED		 295static inline u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offt)
296{
297 return *(((unsigned long *)per_cpu_ptr(mib, cpu)) + offt);
298}
299
698365fa 300unsigned long snmp_fold_field(void __percpu *mib, int offt);
4ce3c183 301#if BITS_PER_LONG==32
c4c6bc31
R		 302u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
303 size_t syncp_offset);
698365fa 304u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
4ce3c183 305#else
c4c6bc31
R		 306static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
307 size_t syncp_offset)
308{
309 return snmp_get_cpu_field(mib, cpu, offct);
310
311}
312
698365fa 313static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
4ce3c183
ED		 314{
315 return snmp_fold_field(mib, offt);
316}
317#endif
33490170 318
6348ef2d
JH		 319#define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \
320{ \
321 int i, c; \
322 for_each_possible_cpu(c) { \
323 for (i = 0; stats_list[i].name; i++) \
324 buff64[i] += snmp_get_cpu_field64( \
325 mib_statistic, \
326 c, stats_list[i].entry, \
327 offset); \
328 } \
329}
330
331#define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \
332{ \
333 int i, c; \
334 for_each_possible_cpu(c) { \
335 for (i = 0; stats_list[i].name; i++) \
336 buff[i] += snmp_get_cpu_field( \
337 mib_statistic, \
338 c, stats_list[i].entry); \
339 } \
340}
341
0bbf87d8 342void inet_get_local_port_range(struct net *net, int *low, int *high);
227b60f5 343
fcd77db0 344#ifdef CONFIG_SYSCTL
66e2f5f7 345static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
e3826f1e 346{
122ff243 347 if (!net->ipv4.sysctl_local_reserved_ports)
30429fba 348 return false;
122ff243 349 return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
e3826f1e 350}
20e61da7
WC		 351
352static inline bool sysctl_dev_name_is_allowed(const char *name)
353{
354 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0;
355}
356
82f31ebf 357static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
4548b683 358{
82f31ebf 359 return port < net->ipv4.sysctl_ip_prot_sock;
4548b683
KJ		 360}
361
122ff243 362#else
66e2f5f7 363static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
122ff243 364{
30429fba 365 return false;
122ff243 366}
4548b683 367
82f31ebf 368static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
4548b683 369{
82f31ebf 370 return port < PROT_SOCK;
4548b683 371}
122ff243 372#endif
e3826f1e 373
822c8685
DD		 374__be32 inet_current_timestamp(void);
375
20380731
ACM		 376/* From inetpeer.c */
377extern int inet_peer_threshold;
378extern int inet_peer_minttl;
379extern int inet_peer_maxttl;
20380731 380
5c3a0fd7 381void ipfrag_init(void);
20380731 382
5c3a0fd7 383void ip_static_sysctl_init(void);
bd7b1533 384
e110861f
LC		 385#define IP4_REPLY_MARK(net, mark) \
386 ((net)->ipv4.sysctl_fwmark_reflect ? (mark) : 0)
387
d18cd551
DM		 388static inline bool ip_is_fragment(const struct iphdr *iph)
389{
390 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
391}
392
1da177e4 393#ifdef CONFIG_INET
14c85021
ACM		 394#include <net/dst.h>
395
1da177e4
LT		 396/* The function in 2.2 was invalid, producing wrong result for
397 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
398static inline
399int ip_decrease_ttl(struct iphdr *iph)
400{
5c78f275
AV		 401 u32 check = (__force u32)iph->check;
402 check += (__force u32)htons(0x0100);
403 iph->check = (__force __sum16)(check + (check>=0xFFFF));
1da177e4
LT		 404 return --iph->ttl;
405}
406
d52e5a7e
SD		 407static inline int ip_mtu_locked(const struct dst_entry *dst)
408{
409 const struct rtable *rt = (const struct rtable *)dst;
410
411 return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU);
412}
413
1da177e4 414static inline
4e3f5d72 415int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
1da177e4 416{
4e3f5d72
ED		 417 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
418
419 return pmtudisc == IP_PMTUDISC_DO ||
420 (pmtudisc == IP_PMTUDISC_WANT &&
d52e5a7e 421 !ip_mtu_locked(dst));
1da177e4
LT		 422}
423
f87c10a8
HFS		 424static inline bool ip_sk_accept_pmtu(const struct sock *sk)
425{
1b346576
HFS		 426 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
427 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
f87c10a8
HFS		 428}
429
430static inline bool ip_sk_use_pmtu(const struct sock *sk)
431{
432 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
433}
434
60ff7467 435static inline bool ip_sk_ignore_df(const struct sock *sk)
1b346576
HFS		 436{
437 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
438 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
439}
440
f87c10a8
HFS		 441static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
442 bool forwarding)
443{
ac6627a2 444 const struct rtable *rt = container_of(dst, struct rtable, dst);
f87c10a8 445 struct net *net = dev_net(dst->dev);
02a1b175 446 unsigned int mtu;
f87c10a8
HFS		 447
448 if (net->ipv4.sysctl_ip_fwd_use_pmtu ||
d52e5a7e 449 ip_mtu_locked(dst) ||
ac6627a2
VF		 450 !forwarding) {
451 mtu = rt->rt_pmtu;
452 if (mtu && time_before(jiffies, rt->dst.expires))
453 goto out;
454 }
f87c10a8 455
02a1b175
MÅ»		 456 /* 'forwarding = true' case should always honour route mtu */
457 mtu = dst_metric_raw(dst, RTAX_MTU);
ac6627a2
VF		 458 if (mtu)
459 goto out;
460
461 mtu = READ_ONCE(dst->dev->mtu);
462
463 if (unlikely(ip_mtu_locked(dst))) {
464 if (rt->rt_uses_gateway && mtu > 576)
465 mtu = 576;
466 }
467
468out:
469 mtu = min_t(unsigned int, mtu, IP_MAX_MTU);
02a1b175 470
fade5641 471 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
f87c10a8
HFS		 472}
473
fedbb6b4
SL		 474static inline unsigned int ip_skb_dst_mtu(struct sock *sk,
475 const struct sk_buff *skb)
f87c10a8 476{
fade5641
VF		 477 unsigned int mtu;
478
caf3f267 479 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
f87c10a8 480 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
caf3f267 481
f87c10a8 482 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
f87c10a8 483 }
caf3f267 484
fade5641
VF		 485 mtu = min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU);
486 return mtu - lwtunnel_headroom(skb_dst(skb)->lwtstate, mtu);
f87c10a8
HFS		 487}
488
767a2217 489struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx,
d7e774f3
DA		 490 int fc_mx_len,
491 struct netlink_ext_ack *extack);
cc5f0eb2
DA		 492static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics)
493{
494 if (fib_metrics != &dst_default_metrics &&
495 refcount_dec_and_test(&fib_metrics->refcnt))
496 kfree(fib_metrics);
497}
a919525a 498
e1255ed4
DA		 499/* ipv4 and ipv6 both use refcounted metrics if it is not the default */
500static inline
501void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics)
502{
503 dst_init_metrics(dst, fib_metrics->metrics, true);
504
505 if (fib_metrics != &dst_default_metrics) {
506 dst->_metrics |= DST_METRICS_REFCOUNTED;
507 refcount_inc(&fib_metrics->refcnt);
508 }
509}
510
1620a336
DA		 511static inline
512void ip_dst_metrics_put(struct dst_entry *dst)
513{
514 struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst);
515
516 if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt))
517 kfree(p);
518}
519
04ca6973 520u32 ip_idents_reserve(u32 hash, int segs);
b6a7719a 521void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
73f156a6 522
b6a7719a
HFS		 523static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
524 struct sock *sk, int segs)
1da177e4 525{
703133de
AA		 526 struct iphdr *iph = ip_hdr(skb);
527
60ff7467 528 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
1da177e4
LT		 529 /* This is only to work around buggy Windows95/2000
530 * VJ compression implementations. If the ID field
531 * does not change, they drop every other packet in
532 * a TCP stream using header compression.
533 */
c720c7e8
ED		 534 if (sk && inet_sk(sk)->inet_daddr) {
535 iph->id = htons(inet_sk(sk)->inet_id);
73f156a6
ED		 536 inet_sk(sk)->inet_id += segs;
537 } else {
1da177e4 538 iph->id = 0;
73f156a6
ED		 539 }
540 } else {
b6a7719a 541 __ip_select_ident(net, iph, segs);
73f156a6
ED		 542 }
543}
544
b6a7719a
HFS		 545static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
546 struct sock *sk)
73f156a6 547{
b6a7719a 548 ip_select_ident_segs(net, skb, sk, 1);
1da177e4
LT		 549}
550
ed70fcfc
TH		 551static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
552{
553 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
554 skb->len, proto, 0);
555}
556
c3f83241
TH		 557/* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
558 * Equivalent to : flow->v4addrs.src = iph->saddr;
559 * flow->v4addrs.dst = iph->daddr;
560 */
561static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
562 const struct iphdr *iph)
563{
564 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
565 offsetof(typeof(flow->addrs), v4addrs.src) +
566 sizeof(flow->addrs.v4addrs.src));
567 memcpy(&flow->addrs.v4addrs, &iph->saddr, sizeof(flow->addrs.v4addrs));
568 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
569}
570
1933a785
TH		 571static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto)
572{
573 const struct iphdr *iph = skb_gro_network_header(skb);
574
575 return csum_tcpudp_nofold(iph->saddr, iph->daddr,
576 skb_gro_len(skb), proto, 0);
577}
578
1da177e4
LT		 579/*
580 * Map a multicast IP onto multicast MAC for type ethernet.
581 */
582
714e85be 583static inline void ip_eth_mc_map(__be32 naddr, char *buf)
1da177e4 584{
714e85be 585 __u32 addr=ntohl(naddr);
1da177e4
LT		 586 buf[0]=0x01;
587 buf[1]=0x00;
588 buf[2]=0x5e;
589 buf[5]=addr&0xFF;
590 addr>>=8;
591 buf[4]=addr&0xFF;
592 addr>>=8;
593 buf[3]=addr&0x7F;
594}
595
596/*
597 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
598 * Leave P_Key as 0 to be filled in by driver.
599 */
600
a9e527e3 601static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
1da177e4 602{
714e85be 603 __u32 addr;
a9e527e3
RM		 604 unsigned char scope = broadcast[5] & 0xF;
605
1da177e4
LT		 606 buf[0] = 0; /* Reserved */
607 buf[1] = 0xff; /* Multicast QPN */
608 buf[2] = 0xff;
609 buf[3] = 0xff;
714e85be 610 addr = ntohl(naddr);
1da177e4 611 buf[4] = 0xff;
a9e527e3 612 buf[5] = 0x10 | scope; /* scope from broadcast address */
1da177e4
LT		 613 buf[6] = 0x40; /* IPv4 signature */
614 buf[7] = 0x1b;
a9e527e3
RM		 615 buf[8] = broadcast[8]; /* P_Key */
616 buf[9] = broadcast[9];
1da177e4
LT		 617 buf[10] = 0;
618 buf[11] = 0;
619 buf[12] = 0;
620 buf[13] = 0;
621 buf[14] = 0;
622 buf[15] = 0;
623 buf[19] = addr & 0xff;
624 addr >>= 8;
625 buf[18] = addr & 0xff;
626 addr >>= 8;
627 buf[17] = addr & 0xff;
628 addr >>= 8;
629 buf[16] = addr & 0x0f;
630}
631
93ca3bb5
TT		 632static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
633{
634 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0)
635 memcpy(buf, broadcast, 4);
636 else
637 memcpy(buf, &naddr, sizeof(naddr));
638}
639
dfd56b8b 640#if IS_ENABLED(CONFIG_IPV6)
1da177e4
LT		 641#include <linux/ipv6.h>
642#endif
643
644static __inline__ void inet_reset_saddr(struct sock *sk)
645{
c720c7e8 646 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
dfd56b8b 647#if IS_ENABLED(CONFIG_IPV6)
1da177e4
LT		 648 if (sk->sk_family == PF_INET6) {
649 struct ipv6_pinfo *np = inet6_sk(sk);
650
651 memset(&np->saddr, 0, sizeof(np->saddr));
efe4208f 652 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
1da177e4
LT		 653 }
654#endif
655}
656
657#endif
658
72afa352
DA		 659static inline unsigned int ipv4_addr_hash(__be32 ip)
660{
661 return (__force unsigned int) ip;
662}
663
f0b1e64c
MKL		 664static inline u32 ipv4_portaddr_hash(const struct net *net,
665 __be32 saddr,
666 unsigned int port)
667{
668 return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port;
669}
670
5c3a0fd7 671bool ip_call_ra_chain(struct sk_buff *skb);
1da177e4
LT		 672
673/*
b798232f 674 * Functions provided by ip_fragment.c
1da177e4
LT		 675 */
676
fd2c3ef7 677enum ip_defrag_users {
1da177e4
LT		 678 IP_DEFRAG_LOCAL_DELIVER,
679 IP_DEFRAG_CALL_RA_CHAIN,
680 IP_DEFRAG_CONNTRACK_IN,
4be929be 681 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
1da177e4 682 IP_DEFRAG_CONNTRACK_OUT,
4be929be 683 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
8fa9ff68 684 IP_DEFRAG_CONNTRACK_BRIDGE_IN,
4be929be 685 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
1da177e4
LT		 686 IP_DEFRAG_VS_IN,
687 IP_DEFRAG_VS_OUT,
595fc71b
DM		 688 IP_DEFRAG_VS_FWD,
689 IP_DEFRAG_AF_PACKET,
bc416d97 690 IP_DEFRAG_MACVLAN,
1da177e4
LT		 691};
692
5cf42280
AZ		 693/* Return true if the value of 'user' is between 'lower_bond'
694 * and 'upper_bond' inclusively.
695 */
696static inline bool ip_defrag_user_in_between(u32 user,
697 enum ip_defrag_users lower_bond,
698 enum ip_defrag_users upper_bond)
699{
700 return user >= lower_bond && user <= upper_bond;
701}
702
19bcf9f2 703int ip_defrag(struct net *net, struct sk_buff *skb, u32 user);
bc416d97 704#ifdef CONFIG_INET
19bcf9f2 705struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user);
bc416d97 706#else
19bcf9f2 707static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
bc416d97
ED		 708{
709 return skb;
710}
711#endif
1da177e4
LT		 712
713/*
714 * Functions provided by ip_forward.c
715 */
82695b30 716
5c3a0fd7 717int ip_forward(struct sk_buff *skb);
82695b30 718
1da177e4
LT		 719/*
720 * Functions provided by ip_options.c
721 */
82695b30 722
5c3a0fd7
JP		 723void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
724 __be32 daddr, struct rtable *rt, int is_frag);
24a2d43d 725
91ed1e66
PA		 726int __ip_options_echo(struct net *net, struct ip_options *dopt,
727 struct sk_buff *skb, const struct ip_options *sopt);
728static inline int ip_options_echo(struct net *net, struct ip_options *dopt,
729 struct sk_buff *skb)
24a2d43d 730{
91ed1e66 731 return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt);
24a2d43d
ED		 732}
733
5c3a0fd7 734void ip_options_fragment(struct sk_buff *skb);
3da1ed7a
NS		 735int __ip_options_compile(struct net *net, struct ip_options *opt,
736 struct sk_buff *skb, __be32 *info);
5c3a0fd7
JP		 737int ip_options_compile(struct net *net, struct ip_options *opt,
738 struct sk_buff *skb);
739int ip_options_get(struct net *net, struct ip_options_rcu **optp,
de40a3e8 740 sockptr_t data, int optlen);
5c3a0fd7
JP		 741void ip_options_undo(struct ip_options *opt);
742void ip_forward_options(struct sk_buff *skb);
8c83f2df 743int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev);
1da177e4
LT		 744
745/*
746 * Functions provided by ip_sockglue.c
747 */
748
fbf8866d 749void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
ad959036
PA		 750void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
751 struct sk_buff *skb, int tlen, int offset);
24025c46 752int ip_cmsg_send(struct sock *sk, struct msghdr *msg,
c8e6ad08 753 struct ipcm_cookie *ipc, bool allow_ipv6);
020e71a3 754DECLARE_STATIC_KEY_FALSE(ip4_min_ttl);
a7b75c5a 755int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
5c3a0fd7
JP		 756 unsigned int optlen);
757int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
758 int __user *optlen);
5c3a0fd7
JP		 759int ip_ra_control(struct sock *sk, unsigned char on,
760 void (*destructor)(struct sock *));
761
85fbaa75 762int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
5c3a0fd7
JP		 763void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
764 u32 info, u8 *payload);
765void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
766 u32 info);
1da177e4 767
5961de9f
TH		 768static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
769{
ad959036 770 ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0);
5961de9f
TH		 771}
772
4cdf507d
ED		 773bool icmp_global_allow(void);
774extern int sysctl_icmp_msgs_per_sec;
775extern int sysctl_icmp_msgs_burst;
776
20380731 777#ifdef CONFIG_PROC_FS
5c3a0fd7 778int ip_misc_proc_init(void);
20380731
ACM		 779#endif
780
5e1a99ea 781int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family,
404eb77e
RP		 782 struct netlink_ext_ack *extack);
783
501a90c9
ED		 784static inline bool inetdev_valid_mtu(unsigned int mtu)
785{
786 return likely(mtu >= IPV4_MIN_MTU);
787}
788
c4e446bf 789void ip_sock_set_freebind(struct sock *sk);
2de569bd 790int ip_sock_set_mtu_discover(struct sock *sk, int val);
c1f9ec57 791void ip_sock_set_pktinfo(struct sock *sk);
db45c0ef 792void ip_sock_set_recverr(struct sock *sk);
6ebf71ba
CH		 793void ip_sock_set_tos(struct sock *sk, int val);
794
1da177e4 795#endif /* _IP_H */
Linux 6.x block layer and io_uring tree(s)