Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0-or-later */
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 *
11 * Authors: Ross Biro
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
17 */
18#ifndef _IP_H
19#define _IP_H
20
21#include <linux/types.h>
22#include <linux/ip.h>
23#include <linux/in.h>
24#include <linux/skbuff.h>
25#include <linux/jhash.h>
26#include <linux/sockptr.h>
27#include <linux/static_key.h>
28
29#include <net/inet_sock.h>
30#include <net/route.h>
31#include <net/snmp.h>
32#include <net/flow.h>
33#include <net/flow_dissector.h>
34#include <net/netns/hash.h>
35#include <net/lwtunnel.h>
36
37#define IPV4_MAX_PMTU 65535U /* RFC 2675, Section 5.1 */
38#define IPV4_MIN_MTU 68 /* RFC 791 */
39
40extern unsigned int sysctl_fib_sync_mem;
41extern unsigned int sysctl_fib_sync_mem_min;
42extern unsigned int sysctl_fib_sync_mem_max;
43
44struct sock;
45
46struct inet_skb_parm {
47 int iif;
48 struct ip_options opt; /* Compiled IP options */
49 u16 flags;
50
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)
57#define IPSKB_FRAG_PMTU BIT(6)
58#define IPSKB_L3SLAVE BIT(7)
59#define IPSKB_NOPOLICY BIT(8)
60
61 u16 frag_max_size;
62};
63
64static inline bool ipv4_l3mdev_skb(u16 flags)
65{
66 return !!(flags & IPSKB_L3SLAVE);
67}
68
69static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
70{
71 return ip_hdr(skb)->ihl * 4;
72}
73
74struct ipcm_cookie {
75 struct sockcm_cookie sockc;
76 __be32 addr;
77 int oif;
78 struct ip_options_rcu *opt;
79 __u8 protocol;
80 __u8 ttl;
81 __s16 tos;
82 char priority;
83 __u16 gso_size;
84};
85
86static inline void ipcm_init(struct ipcm_cookie *ipcm)
87{
88 *ipcm = (struct ipcm_cookie) { .tos = -1 };
89}
90
91static inline void ipcm_init_sk(struct ipcm_cookie *ipcm,
92 const struct inet_sock *inet)
93{
94 ipcm_init(ipcm);
95
96 ipcm->sockc.mark = READ_ONCE(inet->sk.sk_mark);
97 ipcm->sockc.tsflags = inet->sk.sk_tsflags;
98 ipcm->oif = READ_ONCE(inet->sk.sk_bound_dev_if);
99 ipcm->addr = inet->inet_saddr;
100 ipcm->protocol = inet->inet_num;
101}
102
103#define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
104#define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
105
106/* return enslaved device index if relevant */
107static inline int inet_sdif(const struct sk_buff *skb)
108{
109#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
110 if (skb && ipv4_l3mdev_skb(IPCB(skb)->flags))
111 return IPCB(skb)->iif;
112#endif
113 return 0;
114}
115
116/* Special input handler for packets caught by router alert option.
117 They are selected only by protocol field, and then processed likely
118 local ones; but only if someone wants them! Otherwise, router
119 not running rsvpd will kill RSVP.
120
121 It is user level problem, what it will make with them.
122 I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
123 but receiver should be enough clever f.e. to forward mtrace requests,
124 sent to multicast group to reach destination designated router.
125 */
126
127struct ip_ra_chain {
128 struct ip_ra_chain __rcu *next;
129 struct sock *sk;
130 union {
131 void (*destructor)(struct sock *);
132 struct sock *saved_sk;
133 };
134 struct rcu_head rcu;
135};
136
137/* IP flags. */
138#define IP_CE 0x8000 /* Flag: "Congestion" */
139#define IP_DF 0x4000 /* Flag: "Don't Fragment" */
140#define IP_MF 0x2000 /* Flag: "More Fragments" */
141#define IP_OFFSET 0x1FFF /* "Fragment Offset" part */
142
143#define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */
144
145struct msghdr;
146struct net_device;
147struct packet_type;
148struct rtable;
149struct sockaddr;
150
151int igmp_mc_init(void);
152
153/*
154 * Functions provided by ip.c
155 */
156
157int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
158 __be32 saddr, __be32 daddr,
159 struct ip_options_rcu *opt, u8 tos);
160int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
161 struct net_device *orig_dev);
162void ip_list_rcv(struct list_head *head, struct packet_type *pt,
163 struct net_device *orig_dev);
164int ip_local_deliver(struct sk_buff *skb);
165void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int proto);
166int ip_mr_input(struct sk_buff *skb);
167int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb);
168int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb);
169int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
170 int (*output)(struct net *, struct sock *, struct sk_buff *));
171
172struct ip_fraglist_iter {
173 struct sk_buff *frag;
174 struct iphdr *iph;
175 int offset;
176 unsigned int hlen;
177};
178
179void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph,
180 unsigned int hlen, struct ip_fraglist_iter *iter);
181void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter);
182
183static inline struct sk_buff *ip_fraglist_next(struct ip_fraglist_iter *iter)
184{
185 struct sk_buff *skb = iter->frag;
186
187 iter->frag = skb->next;
188 skb_mark_not_on_list(skb);
189
190 return skb;
191}
192
193struct ip_frag_state {
194 bool DF;
195 unsigned int hlen;
196 unsigned int ll_rs;
197 unsigned int mtu;
198 unsigned int left;
199 int offset;
200 int ptr;
201 __be16 not_last_frag;
202};
203
204void ip_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int ll_rs,
205 unsigned int mtu, bool DF, struct ip_frag_state *state);
206struct sk_buff *ip_frag_next(struct sk_buff *skb,
207 struct ip_frag_state *state);
208
209void ip_send_check(struct iphdr *ip);
210int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
211int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
212
213int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
214 __u8 tos);
215void ip_init(void);
216int ip_append_data(struct sock *sk, struct flowi4 *fl4,
217 int getfrag(void *from, char *to, int offset, int len,
218 int odd, struct sk_buff *skb),
219 void *from, int len, int protolen,
220 struct ipcm_cookie *ipc,
221 struct rtable **rt,
222 unsigned int flags);
223int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
224 struct sk_buff *skb);
225struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
226 struct sk_buff_head *queue,
227 struct inet_cork *cork);
228int ip_send_skb(struct net *net, struct sk_buff *skb);
229int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
230void ip_flush_pending_frames(struct sock *sk);
231struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4,
232 int getfrag(void *from, char *to, int offset,
233 int len, int odd, struct sk_buff *skb),
234 void *from, int length, int transhdrlen,
235 struct ipcm_cookie *ipc, struct rtable **rtp,
236 struct inet_cork *cork, unsigned int flags);
237
238int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
239
240static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
241{
242 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
243}
244
245/* Get the route scope that should be used when sending a packet. */
246static inline u8 ip_sendmsg_scope(const struct inet_sock *inet,
247 const struct ipcm_cookie *ipc,
248 const struct msghdr *msg)
249{
250 if (sock_flag(&inet->sk, SOCK_LOCALROUTE) ||
251 msg->msg_flags & MSG_DONTROUTE ||
252 (ipc->opt && ipc->opt->opt.is_strictroute))
253 return RT_SCOPE_LINK;
254
255 return RT_SCOPE_UNIVERSE;
256}
257
258static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
259{
260 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
261}
262
263/* datagram.c */
264int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
265int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
266
267void ip4_datagram_release_cb(struct sock *sk);
268
269struct ip_reply_arg {
270 struct kvec iov[1];
271 int flags;
272 __wsum csum;
273 int csumoffset; /* u16 offset of csum in iov[0].iov_base */
274 /* -1 if not needed */
275 int bound_dev_if;
276 u8 tos;
277 kuid_t uid;
278};
279
280#define IP_REPLY_ARG_NOSRCCHECK 1
281
282static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
283{
284 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
285}
286
287void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
288 const struct ip_options *sopt,
289 __be32 daddr, __be32 saddr,
290 const struct ip_reply_arg *arg,
291 unsigned int len, u64 transmit_time, u32 txhash);
292
293#define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field)
294#define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field)
295#define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
296#define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
297#define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
298#define __IP_UPD_PO_STATS(net, field, val) __SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
299#define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field)
300#define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field)
301#define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
302#define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
303
304static inline u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offt)
305{
306 return *(((unsigned long *)per_cpu_ptr(mib, cpu)) + offt);
307}
308
309unsigned long snmp_fold_field(void __percpu *mib, int offt);
310#if BITS_PER_LONG==32
311u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
312 size_t syncp_offset);
313u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
314#else
315static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
316 size_t syncp_offset)
317{
318 return snmp_get_cpu_field(mib, cpu, offct);
319
320}
321
322static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
323{
324 return snmp_fold_field(mib, offt);
325}
326#endif
327
328#define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \
329{ \
330 int i, c; \
331 for_each_possible_cpu(c) { \
332 for (i = 0; stats_list[i].name; i++) \
333 buff64[i] += snmp_get_cpu_field64( \
334 mib_statistic, \
335 c, stats_list[i].entry, \
336 offset); \
337 } \
338}
339
340#define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \
341{ \
342 int i, c; \
343 for_each_possible_cpu(c) { \
344 for (i = 0; stats_list[i].name; i++) \
345 buff[i] += snmp_get_cpu_field( \
346 mib_statistic, \
347 c, stats_list[i].entry); \
348 } \
349}
350
351void inet_get_local_port_range(const struct net *net, int *low, int *high);
352void inet_sk_get_local_port_range(const struct sock *sk, int *low, int *high);
353
354#ifdef CONFIG_SYSCTL
355static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
356{
357 if (!net->ipv4.sysctl_local_reserved_ports)
358 return false;
359 return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
360}
361
362static inline bool sysctl_dev_name_is_allowed(const char *name)
363{
364 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0;
365}
366
367static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
368{
369 return port < READ_ONCE(net->ipv4.sysctl_ip_prot_sock);
370}
371
372#else
373static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
374{
375 return false;
376}
377
378static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
379{
380 return port < PROT_SOCK;
381}
382#endif
383
384__be32 inet_current_timestamp(void);
385
386/* From inetpeer.c */
387extern int inet_peer_threshold;
388extern int inet_peer_minttl;
389extern int inet_peer_maxttl;
390
391void ipfrag_init(void);
392
393void ip_static_sysctl_init(void);
394
395#define IP4_REPLY_MARK(net, mark) \
396 (READ_ONCE((net)->ipv4.sysctl_fwmark_reflect) ? (mark) : 0)
397
398static inline bool ip_is_fragment(const struct iphdr *iph)
399{
400 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
401}
402
403#ifdef CONFIG_INET
404#include <net/dst.h>
405
406/* The function in 2.2 was invalid, producing wrong result for
407 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
408static inline
409int ip_decrease_ttl(struct iphdr *iph)
410{
411 u32 check = (__force u32)iph->check;
412 check += (__force u32)htons(0x0100);
413 iph->check = (__force __sum16)(check + (check>=0xFFFF));
414 return --iph->ttl;
415}
416
417static inline int ip_mtu_locked(const struct dst_entry *dst)
418{
419 const struct rtable *rt = (const struct rtable *)dst;
420
421 return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU);
422}
423
424static inline
425int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
426{
427 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
428
429 return pmtudisc == IP_PMTUDISC_DO ||
430 (pmtudisc == IP_PMTUDISC_WANT &&
431 !ip_mtu_locked(dst));
432}
433
434static inline bool ip_sk_accept_pmtu(const struct sock *sk)
435{
436 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
437 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
438}
439
440static inline bool ip_sk_use_pmtu(const struct sock *sk)
441{
442 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
443}
444
445static inline bool ip_sk_ignore_df(const struct sock *sk)
446{
447 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
448 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
449}
450
451static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
452 bool forwarding)
453{
454 const struct rtable *rt = container_of(dst, struct rtable, dst);
455 struct net *net = dev_net(dst->dev);
456 unsigned int mtu;
457
458 if (READ_ONCE(net->ipv4.sysctl_ip_fwd_use_pmtu) ||
459 ip_mtu_locked(dst) ||
460 !forwarding) {
461 mtu = rt->rt_pmtu;
462 if (mtu && time_before(jiffies, rt->dst.expires))
463 goto out;
464 }
465
466 /* 'forwarding = true' case should always honour route mtu */
467 mtu = dst_metric_raw(dst, RTAX_MTU);
468 if (mtu)
469 goto out;
470
471 mtu = READ_ONCE(dst->dev->mtu);
472
473 if (unlikely(ip_mtu_locked(dst))) {
474 if (rt->rt_uses_gateway && mtu > 576)
475 mtu = 576;
476 }
477
478out:
479 mtu = min_t(unsigned int, mtu, IP_MAX_MTU);
480
481 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
482}
483
484static inline unsigned int ip_skb_dst_mtu(struct sock *sk,
485 const struct sk_buff *skb)
486{
487 unsigned int mtu;
488
489 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
490 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
491
492 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
493 }
494
495 mtu = min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU);
496 return mtu - lwtunnel_headroom(skb_dst(skb)->lwtstate, mtu);
497}
498
499struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx,
500 int fc_mx_len,
501 struct netlink_ext_ack *extack);
502static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics)
503{
504 if (fib_metrics != &dst_default_metrics &&
505 refcount_dec_and_test(&fib_metrics->refcnt))
506 kfree(fib_metrics);
507}
508
509/* ipv4 and ipv6 both use refcounted metrics if it is not the default */
510static inline
511void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics)
512{
513 dst_init_metrics(dst, fib_metrics->metrics, true);
514
515 if (fib_metrics != &dst_default_metrics) {
516 dst->_metrics |= DST_METRICS_REFCOUNTED;
517 refcount_inc(&fib_metrics->refcnt);
518 }
519}
520
521static inline
522void ip_dst_metrics_put(struct dst_entry *dst)
523{
524 struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst);
525
526 if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt))
527 kfree(p);
528}
529
530void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
531
532static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
533 struct sock *sk, int segs)
534{
535 struct iphdr *iph = ip_hdr(skb);
536
537 /* We had many attacks based on IPID, use the private
538 * generator as much as we can.
539 */
540 if (sk && inet_sk(sk)->inet_daddr) {
541 int val;
542
543 /* avoid atomic operations for TCP,
544 * as we hold socket lock at this point.
545 */
546 if (sk_is_tcp(sk)) {
547 sock_owned_by_me(sk);
548 val = atomic_read(&inet_sk(sk)->inet_id);
549 atomic_set(&inet_sk(sk)->inet_id, val + segs);
550 } else {
551 val = atomic_add_return(segs, &inet_sk(sk)->inet_id);
552 }
553 iph->id = htons(val);
554 return;
555 }
556 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
557 iph->id = 0;
558 } else {
559 /* Unfortunately we need the big hammer to get a suitable IPID */
560 __ip_select_ident(net, iph, segs);
561 }
562}
563
564static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
565 struct sock *sk)
566{
567 ip_select_ident_segs(net, skb, sk, 1);
568}
569
570static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
571{
572 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
573 skb->len, proto, 0);
574}
575
576/* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
577 * Equivalent to : flow->v4addrs.src = iph->saddr;
578 * flow->v4addrs.dst = iph->daddr;
579 */
580static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
581 const struct iphdr *iph)
582{
583 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
584 offsetof(typeof(flow->addrs), v4addrs.src) +
585 sizeof(flow->addrs.v4addrs.src));
586 memcpy(&flow->addrs.v4addrs, &iph->addrs, sizeof(flow->addrs.v4addrs));
587 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
588}
589
590/*
591 * Map a multicast IP onto multicast MAC for type ethernet.
592 */
593
594static inline void ip_eth_mc_map(__be32 naddr, char *buf)
595{
596 __u32 addr=ntohl(naddr);
597 buf[0]=0x01;
598 buf[1]=0x00;
599 buf[2]=0x5e;
600 buf[5]=addr&0xFF;
601 addr>>=8;
602 buf[4]=addr&0xFF;
603 addr>>=8;
604 buf[3]=addr&0x7F;
605}
606
607/*
608 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
609 * Leave P_Key as 0 to be filled in by driver.
610 */
611
612static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
613{
614 __u32 addr;
615 unsigned char scope = broadcast[5] & 0xF;
616
617 buf[0] = 0; /* Reserved */
618 buf[1] = 0xff; /* Multicast QPN */
619 buf[2] = 0xff;
620 buf[3] = 0xff;
621 addr = ntohl(naddr);
622 buf[4] = 0xff;
623 buf[5] = 0x10 | scope; /* scope from broadcast address */
624 buf[6] = 0x40; /* IPv4 signature */
625 buf[7] = 0x1b;
626 buf[8] = broadcast[8]; /* P_Key */
627 buf[9] = broadcast[9];
628 buf[10] = 0;
629 buf[11] = 0;
630 buf[12] = 0;
631 buf[13] = 0;
632 buf[14] = 0;
633 buf[15] = 0;
634 buf[19] = addr & 0xff;
635 addr >>= 8;
636 buf[18] = addr & 0xff;
637 addr >>= 8;
638 buf[17] = addr & 0xff;
639 addr >>= 8;
640 buf[16] = addr & 0x0f;
641}
642
643static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
644{
645 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0)
646 memcpy(buf, broadcast, 4);
647 else
648 memcpy(buf, &naddr, sizeof(naddr));
649}
650
651#if IS_ENABLED(CONFIG_IPV6)
652#include <linux/ipv6.h>
653#endif
654
655static __inline__ void inet_reset_saddr(struct sock *sk)
656{
657 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
658#if IS_ENABLED(CONFIG_IPV6)
659 if (sk->sk_family == PF_INET6) {
660 struct ipv6_pinfo *np = inet6_sk(sk);
661
662 memset(&np->saddr, 0, sizeof(np->saddr));
663 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
664 }
665#endif
666}
667
668#endif
669
670static inline unsigned int ipv4_addr_hash(__be32 ip)
671{
672 return (__force unsigned int) ip;
673}
674
675static inline u32 ipv4_portaddr_hash(const struct net *net,
676 __be32 saddr,
677 unsigned int port)
678{
679 return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port;
680}
681
682bool ip_call_ra_chain(struct sk_buff *skb);
683
684/*
685 * Functions provided by ip_fragment.c
686 */
687
688enum ip_defrag_users {
689 IP_DEFRAG_LOCAL_DELIVER,
690 IP_DEFRAG_CALL_RA_CHAIN,
691 IP_DEFRAG_CONNTRACK_IN,
692 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
693 IP_DEFRAG_CONNTRACK_OUT,
694 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
695 IP_DEFRAG_CONNTRACK_BRIDGE_IN,
696 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
697 IP_DEFRAG_VS_IN,
698 IP_DEFRAG_VS_OUT,
699 IP_DEFRAG_VS_FWD,
700 IP_DEFRAG_AF_PACKET,
701 IP_DEFRAG_MACVLAN,
702};
703
704/* Return true if the value of 'user' is between 'lower_bond'
705 * and 'upper_bond' inclusively.
706 */
707static inline bool ip_defrag_user_in_between(u32 user,
708 enum ip_defrag_users lower_bond,
709 enum ip_defrag_users upper_bond)
710{
711 return user >= lower_bond && user <= upper_bond;
712}
713
714int ip_defrag(struct net *net, struct sk_buff *skb, u32 user);
715#ifdef CONFIG_INET
716struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user);
717#else
718static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
719{
720 return skb;
721}
722#endif
723
724/*
725 * Functions provided by ip_forward.c
726 */
727
728int ip_forward(struct sk_buff *skb);
729
730/*
731 * Functions provided by ip_options.c
732 */
733
734void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
735 __be32 daddr, struct rtable *rt);
736
737int __ip_options_echo(struct net *net, struct ip_options *dopt,
738 struct sk_buff *skb, const struct ip_options *sopt);
739static inline int ip_options_echo(struct net *net, struct ip_options *dopt,
740 struct sk_buff *skb)
741{
742 return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt);
743}
744
745void ip_options_fragment(struct sk_buff *skb);
746int __ip_options_compile(struct net *net, struct ip_options *opt,
747 struct sk_buff *skb, __be32 *info);
748int ip_options_compile(struct net *net, struct ip_options *opt,
749 struct sk_buff *skb);
750int ip_options_get(struct net *net, struct ip_options_rcu **optp,
751 sockptr_t data, int optlen);
752void ip_options_undo(struct ip_options *opt);
753void ip_forward_options(struct sk_buff *skb);
754int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev);
755
756/*
757 * Functions provided by ip_sockglue.c
758 */
759
760void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
761void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
762 struct sk_buff *skb, int tlen, int offset);
763int ip_cmsg_send(struct sock *sk, struct msghdr *msg,
764 struct ipcm_cookie *ipc, bool allow_ipv6);
765DECLARE_STATIC_KEY_FALSE(ip4_min_ttl);
766int do_ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
767 unsigned int optlen);
768int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
769 unsigned int optlen);
770int do_ip_getsockopt(struct sock *sk, int level, int optname,
771 sockptr_t optval, sockptr_t optlen);
772int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
773 int __user *optlen);
774int ip_ra_control(struct sock *sk, unsigned char on,
775 void (*destructor)(struct sock *));
776
777int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
778void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
779 u32 info, u8 *payload);
780void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
781 u32 info);
782
783static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
784{
785 ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0);
786}
787
788bool icmp_global_allow(void);
789extern int sysctl_icmp_msgs_per_sec;
790extern int sysctl_icmp_msgs_burst;
791
792#ifdef CONFIG_PROC_FS
793int ip_misc_proc_init(void);
794#endif
795
796int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family,
797 struct netlink_ext_ack *extack);
798
799static inline bool inetdev_valid_mtu(unsigned int mtu)
800{
801 return likely(mtu >= IPV4_MIN_MTU);
802}
803
804void ip_sock_set_freebind(struct sock *sk);
805int ip_sock_set_mtu_discover(struct sock *sk, int val);
806void ip_sock_set_pktinfo(struct sock *sk);
807void ip_sock_set_recverr(struct sock *sk);
808void ip_sock_set_tos(struct sock *sk, int val);
809void __ip_sock_set_tos(struct sock *sk, int val);
810
811#endif /* _IP_H */