1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * PF_INET6 socket protocol family
4 * Linux INET6 implementation
5 *
6 * Authors:
7 * Pedro Roque <roque@di.fc.ul.pt>
8 *
9 * Adapted from linux/net/ipv4/af_inet.c
10 *
11 * Fixes:
12 * piggy, Karl Knutson : Socket protocol table
13 * Hideaki YOSHIFUJI : sin6_scope_id support
14 * Arnaldo Melo : check proc_net_create return, cleanups
15 */
16
17 #define pr_fmt(fmt) "IPv6: " fmt
18
19 #include <linux/module.h>
20 #include <linux/capability.h>
21 #include <linux/errno.h>
22 #include <linux/types.h>
23 #include <linux/socket.h>
24 #include <linux/in.h>
25 #include <linux/kernel.h>
26 #include <linux/timer.h>
27 #include <linux/string.h>
28 #include <linux/sockios.h>
29 #include <linux/net.h>
30 #include <linux/fcntl.h>
31 #include <linux/mm.h>
32 #include <linux/interrupt.h>
33 #include <linux/proc_fs.h>
34 #include <linux/stat.h>
35 #include <linux/init.h>
36 #include <linux/slab.h>
37
38 #include <linux/inet.h>
39 #include <linux/netdevice.h>
40 #include <linux/icmpv6.h>
41 #include <linux/netfilter_ipv6.h>
42
43 #include <net/ip.h>
44 #include <net/ipv6.h>
45 #include <net/udp.h>
46 #include <net/udplite.h>
47 #include <net/tcp.h>
48 #include <net/ping.h>
49 #include <net/protocol.h>
50 #include <net/inet_common.h>
51 #include <net/route.h>
52 #include <net/transp_v6.h>
53 #include <net/ip6_route.h>
54 #include <net/addrconf.h>
55 #include <net/ipv6_stubs.h>
56 #include <net/ndisc.h>
57 #ifdef CONFIG_IPV6_TUNNEL
58 #include <net/ip6_tunnel.h>
59 #endif
60 #include <net/calipso.h>
61 #include <net/seg6.h>
62
63 #include <linux/uaccess.h>
64 #include <linux/mroute6.h>
65
66 #include "ip6_offload.h"
67
68 MODULE_AUTHOR("Cast of dozens");
69 MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
70 MODULE_LICENSE("GPL");
71
72 /* The inetsw6 table contains everything that inet6_create needs to
73 * build a new socket.
74 */
75 static struct list_head inetsw6[SOCK_MAX];
76 static DEFINE_SPINLOCK(inetsw6_lock);
77
78 struct ipv6_params ipv6_defaults = {
79 .disable_ipv6 = 0,
80 .autoconf = 1,
81 };
82
83 static int disable_ipv6_mod;
84
85 module_param_named(disable, disable_ipv6_mod, int, 0444);
86 MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
87
88 module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
89 MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
90
91 module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
92 MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
93
ipv6_mod_enabled(void)94 bool ipv6_mod_enabled(void)
95 {
96 return disable_ipv6_mod == 0;
97 }
98 EXPORT_SYMBOL_GPL(ipv6_mod_enabled);
99
inet6_sk_generic(struct sock * sk)100 static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
101 {
102 const int offset = sk->sk_prot->obj_size - sizeof(struct ipv6_pinfo);
103
104 return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
105 }
106
inet6_create(struct net * net,struct socket * sock,int protocol,int kern)107 static int inet6_create(struct net *net, struct socket *sock, int protocol,
108 int kern)
109 {
110 struct inet_sock *inet;
111 struct ipv6_pinfo *np;
112 struct sock *sk;
113 struct inet_protosw *answer;
114 struct proto *answer_prot;
115 unsigned char answer_flags;
116 int try_loading_module = 0;
117 int err;
118
119 if (protocol < 0 || protocol >= IPPROTO_MAX)
120 return -EINVAL;
121
122 /* Look for the requested type/protocol pair. */
123 lookup_protocol:
124 err = -ESOCKTNOSUPPORT;
125 rcu_read_lock();
126 list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
127
128 err = 0;
129 /* Check the non-wild match. */
130 if (protocol == answer->protocol) {
131 if (protocol != IPPROTO_IP)
132 break;
133 } else {
134 /* Check for the two wild cases. */
135 if (IPPROTO_IP == protocol) {
136 protocol = answer->protocol;
137 break;
138 }
139 if (IPPROTO_IP == answer->protocol)
140 break;
141 }
142 err = -EPROTONOSUPPORT;
143 }
144
145 if (err) {
146 if (try_loading_module < 2) {
147 rcu_read_unlock();
148 /*
149 * Be more specific, e.g. net-pf-10-proto-132-type-1
150 * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
151 */
152 if (++try_loading_module == 1)
153 request_module("net-pf-%d-proto-%d-type-%d",
154 PF_INET6, protocol, sock->type);
155 /*
156 * Fall back to generic, e.g. net-pf-10-proto-132
157 * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
158 */
159 else
160 request_module("net-pf-%d-proto-%d",
161 PF_INET6, protocol);
162 goto lookup_protocol;
163 } else
164 goto out_rcu_unlock;
165 }
166
167 err = -EPERM;
168 if (sock->type == SOCK_RAW && !kern &&
169 !ns_capable(net->user_ns, CAP_NET_RAW))
170 goto out_rcu_unlock;
171
172 sock->ops = answer->ops;
173 answer_prot = answer->prot;
174 answer_flags = answer->flags;
175 rcu_read_unlock();
176
177 WARN_ON(!answer_prot->slab);
178
179 err = -ENOBUFS;
180 sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot, kern);
181 if (!sk)
182 goto out;
183
184 sock_init_data(sock, sk);
185
186 err = 0;
187 if (INET_PROTOSW_REUSE & answer_flags)
188 sk->sk_reuse = SK_CAN_REUSE;
189
190 inet = inet_sk(sk);
191 inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
192
193 if (SOCK_RAW == sock->type) {
194 inet->inet_num = protocol;
195 if (IPPROTO_RAW == protocol)
196 inet->hdrincl = 1;
197 }
198
199 sk->sk_destruct = inet_sock_destruct;
200 sk->sk_family = PF_INET6;
201 sk->sk_protocol = protocol;
202
203 sk->sk_backlog_rcv = answer->prot->backlog_rcv;
204
205 inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
206 np->hop_limit = -1;
207 np->mcast_hops = IPV6_DEFAULT_MCASTHOPS;
208 np->mc_loop = 1;
209 np->mc_all = 1;
210 np->pmtudisc = IPV6_PMTUDISC_WANT;
211 np->repflow = net->ipv6.sysctl.flowlabel_reflect & FLOWLABEL_REFLECT_ESTABLISHED;
212 sk->sk_ipv6only = net->ipv6.sysctl.bindv6only;
213
214 /* Init the ipv4 part of the socket since we can have sockets
215 * using v6 API for ipv4.
216 */
217 inet->uc_ttl = -1;
218
219 inet->mc_loop = 1;
220 inet->mc_ttl = 1;
221 inet->mc_index = 0;
222 inet->mc_list = NULL;
223 inet->rcv_tos = 0;
224
225 if (net->ipv4.sysctl_ip_no_pmtu_disc)
226 inet->pmtudisc = IP_PMTUDISC_DONT;
227 else
228 inet->pmtudisc = IP_PMTUDISC_WANT;
229 /*
230 * Increment only the relevant sk_prot->socks debug field, this changes
231 * the previous behaviour of incrementing both the equivalent to
232 * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
233 *
234 * This allows better debug granularity as we'll know exactly how many
235 * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
236 * transport protocol socks. -acme
237 */
238 sk_refcnt_debug_inc(sk);
239
240 if (inet->inet_num) {
241 /* It assumes that any protocol which allows
242 * the user to assign a number at socket
243 * creation time automatically shares.
244 */
245 inet->inet_sport = htons(inet->inet_num);
246 err = sk->sk_prot->hash(sk);
247 if (err) {
248 sk_common_release(sk);
249 goto out;
250 }
251 }
252 if (sk->sk_prot->init) {
253 err = sk->sk_prot->init(sk);
254 if (err) {
255 sk_common_release(sk);
256 goto out;
257 }
258 }
259
260 if (!kern) {
261 err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
262 if (err) {
263 sk_common_release(sk);
264 goto out;
265 }
266 }
267 out:
268 return err;
269 out_rcu_unlock:
270 rcu_read_unlock();
271 goto out;
272 }
273
__inet6_bind(struct sock * sk,struct sockaddr * uaddr,int addr_len,bool force_bind_address_no_port,bool with_lock)274 static int __inet6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len,
275 bool force_bind_address_no_port, bool with_lock)
276 {
277 struct sockaddr_in6 *addr = (struct sockaddr_in6 *)uaddr;
278 struct inet_sock *inet = inet_sk(sk);
279 struct ipv6_pinfo *np = inet6_sk(sk);
280 struct net *net = sock_net(sk);
281 __be32 v4addr = 0;
282 unsigned short snum;
283 bool saved_ipv6only;
284 int addr_type = 0;
285 int err = 0;
286
287 if (addr->sin6_family != AF_INET6)
288 return -EAFNOSUPPORT;
289
290 addr_type = ipv6_addr_type(&addr->sin6_addr);
291 if ((addr_type & IPV6_ADDR_MULTICAST) && sk->sk_type == SOCK_STREAM)
292 return -EINVAL;
293
294 snum = ntohs(addr->sin6_port);
295 if (snum && snum < inet_prot_sock(net) &&
296 !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
297 return -EACCES;
298
299 if (with_lock)
300 lock_sock(sk);
301
302 /* Check these errors (active socket, double bind). */
303 if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
304 err = -EINVAL;
305 goto out;
306 }
307
308 /* Check if the address belongs to the host. */
309 if (addr_type == IPV6_ADDR_MAPPED) {
310 struct net_device *dev = NULL;
311 int chk_addr_ret;
312
313 /* Binding to v4-mapped address on a v6-only socket
314 * makes no sense
315 */
316 if (sk->sk_ipv6only) {
317 err = -EINVAL;
318 goto out;
319 }
320
321 rcu_read_lock();
322 if (sk->sk_bound_dev_if) {
323 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
324 if (!dev) {
325 err = -ENODEV;
326 goto out_unlock;
327 }
328 }
329
330 /* Reproduce AF_INET checks to make the bindings consistent */
331 v4addr = addr->sin6_addr.s6_addr32[3];
332 chk_addr_ret = inet_addr_type_dev_table(net, dev, v4addr);
333 rcu_read_unlock();
334
335 if (!inet_can_nonlocal_bind(net, inet) &&
336 v4addr != htonl(INADDR_ANY) &&
337 chk_addr_ret != RTN_LOCAL &&
338 chk_addr_ret != RTN_MULTICAST &&
339 chk_addr_ret != RTN_BROADCAST) {
340 err = -EADDRNOTAVAIL;
341 goto out;
342 }
343 } else {
344 if (addr_type != IPV6_ADDR_ANY) {
345 struct net_device *dev = NULL;
346
347 rcu_read_lock();
348 if (__ipv6_addr_needs_scope_id(addr_type)) {
349 if (addr_len >= sizeof(struct sockaddr_in6) &&
350 addr->sin6_scope_id) {
351 /* Override any existing binding, if another one
352 * is supplied by user.
353 */
354 sk->sk_bound_dev_if = addr->sin6_scope_id;
355 }
356
357 /* Binding to link-local address requires an interface */
358 if (!sk->sk_bound_dev_if) {
359 err = -EINVAL;
360 goto out_unlock;
361 }
362 }
363
364 if (sk->sk_bound_dev_if) {
365 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
366 if (!dev) {
367 err = -ENODEV;
368 goto out_unlock;
369 }
370 }
371
372 /* ipv4 addr of the socket is invalid. Only the
373 * unspecified and mapped address have a v4 equivalent.
374 */
375 v4addr = LOOPBACK4_IPV6;
376 if (!(addr_type & IPV6_ADDR_MULTICAST)) {
377 if (!ipv6_can_nonlocal_bind(net, inet) &&
378 !ipv6_chk_addr(net, &addr->sin6_addr,
379 dev, 0)) {
380 err = -EADDRNOTAVAIL;
381 goto out_unlock;
382 }
383 }
384 rcu_read_unlock();
385 }
386 }
387
388 inet->inet_rcv_saddr = v4addr;
389 inet->inet_saddr = v4addr;
390
391 sk->sk_v6_rcv_saddr = addr->sin6_addr;
392
393 if (!(addr_type & IPV6_ADDR_MULTICAST))
394 np->saddr = addr->sin6_addr;
395
396 saved_ipv6only = sk->sk_ipv6only;
397 if (addr_type != IPV6_ADDR_ANY && addr_type != IPV6_ADDR_MAPPED)
398 sk->sk_ipv6only = 1;
399
400 /* Make sure we are allowed to bind here. */
401 if (snum || !(inet->bind_address_no_port ||
402 force_bind_address_no_port)) {
403 if (sk->sk_prot->get_port(sk, snum)) {
404 sk->sk_ipv6only = saved_ipv6only;
405 inet_reset_saddr(sk);
406 err = -EADDRINUSE;
407 goto out;
408 }
409 err = BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk);
410 if (err) {
411 sk->sk_ipv6only = saved_ipv6only;
412 inet_reset_saddr(sk);
413 goto out;
414 }
415 }
416
417 if (addr_type != IPV6_ADDR_ANY)
418 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
419 if (snum)
420 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
421 inet->inet_sport = htons(inet->inet_num);
422 inet->inet_dport = 0;
423 inet->inet_daddr = 0;
424 out:
425 if (with_lock)
426 release_sock(sk);
427 return err;
428 out_unlock:
429 rcu_read_unlock();
430 goto out;
431 }
432
433 /* bind for INET6 API */
inet6_bind(struct socket * sock,struct sockaddr * uaddr,int addr_len)434 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
435 {
436 struct sock *sk = sock->sk;
437 int err = 0;
438
439 /* If the socket has its own bind function then use it. */
440 if (sk->sk_prot->bind)
441 return sk->sk_prot->bind(sk, uaddr, addr_len);
442
443 if (addr_len < SIN6_LEN_RFC2133)
444 return -EINVAL;
445
446 /* BPF prog is run before any checks are done so that if the prog
447 * changes context in a wrong way it will be caught.
448 */
449 err = BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr);
450 if (err)
451 return err;
452
453 return __inet6_bind(sk, uaddr, addr_len, false, true);
454 }
455 EXPORT_SYMBOL(inet6_bind);
456
inet6_release(struct socket * sock)457 int inet6_release(struct socket *sock)
458 {
459 struct sock *sk = sock->sk;
460
461 if (!sk)
462 return -EINVAL;
463
464 /* Free mc lists */
465 ipv6_sock_mc_close(sk);
466
467 /* Free ac lists */
468 ipv6_sock_ac_close(sk);
469
470 return inet_release(sock);
471 }
472 EXPORT_SYMBOL(inet6_release);
473
inet6_destroy_sock(struct sock * sk)474 void inet6_destroy_sock(struct sock *sk)
475 {
476 struct ipv6_pinfo *np = inet6_sk(sk);
477 struct sk_buff *skb;
478 struct ipv6_txoptions *opt;
479
480 /* Release rx options */
481
482 skb = xchg(&np->pktoptions, NULL);
483 kfree_skb(skb);
484
485 skb = xchg(&np->rxpmtu, NULL);
486 kfree_skb(skb);
487
488 /* Free flowlabels */
489 fl6_free_socklist(sk);
490
491 /* Free tx options */
492
493 opt = xchg((__force struct ipv6_txoptions **)&np->opt, NULL);
494 if (opt) {
495 atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
496 txopt_put(opt);
497 }
498 }
499 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
500
501 /*
502 * This does both peername and sockname.
503 */
504
inet6_getname(struct socket * sock,struct sockaddr * uaddr,int peer)505 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
506 int peer)
507 {
508 struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr;
509 struct sock *sk = sock->sk;
510 struct inet_sock *inet = inet_sk(sk);
511 struct ipv6_pinfo *np = inet6_sk(sk);
512
513 sin->sin6_family = AF_INET6;
514 sin->sin6_flowinfo = 0;
515 sin->sin6_scope_id = 0;
516 if (peer) {
517 if (!inet->inet_dport)
518 return -ENOTCONN;
519 if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
520 peer == 1)
521 return -ENOTCONN;
522 sin->sin6_port = inet->inet_dport;
523 sin->sin6_addr = sk->sk_v6_daddr;
524 if (np->sndflow)
525 sin->sin6_flowinfo = np->flow_label;
526 } else {
527 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
528 sin->sin6_addr = np->saddr;
529 else
530 sin->sin6_addr = sk->sk_v6_rcv_saddr;
531
532 sin->sin6_port = inet->inet_sport;
533 }
534 sin->sin6_scope_id = ipv6_iface_scope_id(&sin->sin6_addr,
535 sk->sk_bound_dev_if);
536 return sizeof(*sin);
537 }
538 EXPORT_SYMBOL(inet6_getname);
539
inet6_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)540 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
541 {
542 struct sock *sk = sock->sk;
543 struct net *net = sock_net(sk);
544
545 switch (cmd) {
546 case SIOCADDRT:
547 case SIOCDELRT:
548
549 return ipv6_route_ioctl(net, cmd, (void __user *)arg);
550
551 case SIOCSIFADDR:
552 return addrconf_add_ifaddr(net, (void __user *) arg);
553 case SIOCDIFADDR:
554 return addrconf_del_ifaddr(net, (void __user *) arg);
555 case SIOCSIFDSTADDR:
556 return addrconf_set_dstaddr(net, (void __user *) arg);
557 default:
558 if (!sk->sk_prot->ioctl)
559 return -ENOIOCTLCMD;
560 return sk->sk_prot->ioctl(sk, cmd, arg);
561 }
562 /*NOTREACHED*/
563 return 0;
564 }
565 EXPORT_SYMBOL(inet6_ioctl);
566
567 INDIRECT_CALLABLE_DECLARE(int udpv6_sendmsg(struct sock *, struct msghdr *,
568 size_t));
inet6_sendmsg(struct socket * sock,struct msghdr * msg,size_t size)569 int inet6_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
570 {
571 struct sock *sk = sock->sk;
572
573 if (unlikely(inet_send_prepare(sk)))
574 return -EAGAIN;
575
576 return INDIRECT_CALL_2(sk->sk_prot->sendmsg, tcp_sendmsg, udpv6_sendmsg,
577 sk, msg, size);
578 }
579
580 INDIRECT_CALLABLE_DECLARE(int udpv6_recvmsg(struct sock *, struct msghdr *,
581 size_t, int, int, int *));
inet6_recvmsg(struct socket * sock,struct msghdr * msg,size_t size,int flags)582 int inet6_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
583 int flags)
584 {
585 struct sock *sk = sock->sk;
586 int addr_len = 0;
587 int err;
588
589 if (likely(!(flags & MSG_ERRQUEUE)))
590 sock_rps_record_flow(sk);
591
592 err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udpv6_recvmsg,
593 sk, msg, size, flags & MSG_DONTWAIT,
594 flags & ~MSG_DONTWAIT, &addr_len);
595 if (err >= 0)
596 msg->msg_namelen = addr_len;
597 return err;
598 }
599
600 const struct proto_ops inet6_stream_ops = {
601 .family = PF_INET6,
602 .owner = THIS_MODULE,
603 .release = inet6_release,
604 .bind = inet6_bind,
605 .connect = inet_stream_connect, /* ok */
606 .socketpair = sock_no_socketpair, /* a do nothing */
607 .accept = inet_accept, /* ok */
608 .getname = inet6_getname,
609 .poll = tcp_poll, /* ok */
610 .ioctl = inet6_ioctl, /* must change */
611 .gettstamp = sock_gettstamp,
612 .listen = inet_listen, /* ok */
613 .shutdown = inet_shutdown, /* ok */
614 .setsockopt = sock_common_setsockopt, /* ok */
615 .getsockopt = sock_common_getsockopt, /* ok */
616 .sendmsg = inet6_sendmsg, /* retpoline's sake */
617 .recvmsg = inet6_recvmsg, /* retpoline's sake */
618 #ifdef CONFIG_MMU
619 .mmap = tcp_mmap,
620 #endif
621 .sendpage = inet_sendpage,
622 .sendmsg_locked = tcp_sendmsg_locked,
623 .sendpage_locked = tcp_sendpage_locked,
624 .splice_read = tcp_splice_read,
625 .read_sock = tcp_read_sock,
626 .peek_len = tcp_peek_len,
627 #ifdef CONFIG_COMPAT
628 .compat_setsockopt = compat_sock_common_setsockopt,
629 .compat_getsockopt = compat_sock_common_getsockopt,
630 #endif
631 .set_rcvlowat = tcp_set_rcvlowat,
632 };
633
634 const struct proto_ops inet6_dgram_ops = {
635 .family = PF_INET6,
636 .owner = THIS_MODULE,
637 .release = inet6_release,
638 .bind = inet6_bind,
639 .connect = inet_dgram_connect, /* ok */
640 .socketpair = sock_no_socketpair, /* a do nothing */
641 .accept = sock_no_accept, /* a do nothing */
642 .getname = inet6_getname,
643 .poll = udp_poll, /* ok */
644 .ioctl = inet6_ioctl, /* must change */
645 .gettstamp = sock_gettstamp,
646 .listen = sock_no_listen, /* ok */
647 .shutdown = inet_shutdown, /* ok */
648 .setsockopt = sock_common_setsockopt, /* ok */
649 .getsockopt = sock_common_getsockopt, /* ok */
650 .sendmsg = inet6_sendmsg, /* retpoline's sake */
651 .recvmsg = inet6_recvmsg, /* retpoline's sake */
652 .mmap = sock_no_mmap,
653 .sendpage = sock_no_sendpage,
654 .set_peek_off = sk_set_peek_off,
655 #ifdef CONFIG_COMPAT
656 .compat_setsockopt = compat_sock_common_setsockopt,
657 .compat_getsockopt = compat_sock_common_getsockopt,
658 #endif
659 };
660
661 static const struct net_proto_family inet6_family_ops = {
662 .family = PF_INET6,
663 .create = inet6_create,
664 .owner = THIS_MODULE,
665 };
666
inet6_register_protosw(struct inet_protosw * p)667 int inet6_register_protosw(struct inet_protosw *p)
668 {
669 struct list_head *lh;
670 struct inet_protosw *answer;
671 struct list_head *last_perm;
672 int protocol = p->protocol;
673 int ret;
674
675 spin_lock_bh(&inetsw6_lock);
676
677 ret = -EINVAL;
678 if (p->type >= SOCK_MAX)
679 goto out_illegal;
680
681 /* If we are trying to override a permanent protocol, bail. */
682 answer = NULL;
683 ret = -EPERM;
684 last_perm = &inetsw6[p->type];
685 list_for_each(lh, &inetsw6[p->type]) {
686 answer = list_entry(lh, struct inet_protosw, list);
687
688 /* Check only the non-wild match. */
689 if (INET_PROTOSW_PERMANENT & answer->flags) {
690 if (protocol == answer->protocol)
691 break;
692 last_perm = lh;
693 }
694
695 answer = NULL;
696 }
697 if (answer)
698 goto out_permanent;
699
700 /* Add the new entry after the last permanent entry if any, so that
701 * the new entry does not override a permanent entry when matched with
702 * a wild-card protocol. But it is allowed to override any existing
703 * non-permanent entry. This means that when we remove this entry, the
704 * system automatically returns to the old behavior.
705 */
706 list_add_rcu(&p->list, last_perm);
707 ret = 0;
708 out:
709 spin_unlock_bh(&inetsw6_lock);
710 return ret;
711
712 out_permanent:
713 pr_err("Attempt to override permanent protocol %d\n", protocol);
714 goto out;
715
716 out_illegal:
717 pr_err("Ignoring attempt to register invalid socket type %d\n",
718 p->type);
719 goto out;
720 }
721 EXPORT_SYMBOL(inet6_register_protosw);
722
723 void
inet6_unregister_protosw(struct inet_protosw * p)724 inet6_unregister_protosw(struct inet_protosw *p)
725 {
726 if (INET_PROTOSW_PERMANENT & p->flags) {
727 pr_err("Attempt to unregister permanent protocol %d\n",
728 p->protocol);
729 } else {
730 spin_lock_bh(&inetsw6_lock);
731 list_del_rcu(&p->list);
732 spin_unlock_bh(&inetsw6_lock);
733
734 synchronize_net();
735 }
736 }
737 EXPORT_SYMBOL(inet6_unregister_protosw);
738
inet6_sk_rebuild_header(struct sock * sk)739 int inet6_sk_rebuild_header(struct sock *sk)
740 {
741 struct ipv6_pinfo *np = inet6_sk(sk);
742 struct dst_entry *dst;
743
744 dst = __sk_dst_check(sk, np->dst_cookie);
745
746 if (!dst) {
747 struct inet_sock *inet = inet_sk(sk);
748 struct in6_addr *final_p, final;
749 struct flowi6 fl6;
750
751 memset(&fl6, 0, sizeof(fl6));
752 fl6.flowi6_proto = sk->sk_protocol;
753 fl6.daddr = sk->sk_v6_daddr;
754 fl6.saddr = np->saddr;
755 fl6.flowlabel = np->flow_label;
756 fl6.flowi6_oif = sk->sk_bound_dev_if;
757 fl6.flowi6_mark = sk->sk_mark;
758 fl6.fl6_dport = inet->inet_dport;
759 fl6.fl6_sport = inet->inet_sport;
760 fl6.flowi6_uid = sk->sk_uid;
761 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
762
763 rcu_read_lock();
764 final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt),
765 &final);
766 rcu_read_unlock();
767
768 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
769 if (IS_ERR(dst)) {
770 sk->sk_route_caps = 0;
771 sk->sk_err_soft = -PTR_ERR(dst);
772 return PTR_ERR(dst);
773 }
774
775 ip6_dst_store(sk, dst, NULL, NULL);
776 }
777
778 return 0;
779 }
780 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
781
ipv6_opt_accepted(const struct sock * sk,const struct sk_buff * skb,const struct inet6_skb_parm * opt)782 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
783 const struct inet6_skb_parm *opt)
784 {
785 const struct ipv6_pinfo *np = inet6_sk(sk);
786
787 if (np->rxopt.all) {
788 if (((opt->flags & IP6SKB_HOPBYHOP) &&
789 (np->rxopt.bits.hopopts || np->rxopt.bits.ohopopts)) ||
790 (ip6_flowinfo((struct ipv6hdr *) skb_network_header(skb)) &&
791 np->rxopt.bits.rxflow) ||
792 (opt->srcrt && (np->rxopt.bits.srcrt ||
793 np->rxopt.bits.osrcrt)) ||
794 ((opt->dst1 || opt->dst0) &&
795 (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
796 return true;
797 }
798 return false;
799 }
800 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
801
802 static struct packet_type ipv6_packet_type __read_mostly = {
803 .type = cpu_to_be16(ETH_P_IPV6),
804 .func = ipv6_rcv,
805 .list_func = ipv6_list_rcv,
806 };
807
ipv6_packet_init(void)808 static int __init ipv6_packet_init(void)
809 {
810 dev_add_pack(&ipv6_packet_type);
811 return 0;
812 }
813
ipv6_packet_cleanup(void)814 static void ipv6_packet_cleanup(void)
815 {
816 dev_remove_pack(&ipv6_packet_type);
817 }
818
ipv6_init_mibs(struct net * net)819 static int __net_init ipv6_init_mibs(struct net *net)
820 {
821 int i;
822
823 net->mib.udp_stats_in6 = alloc_percpu(struct udp_mib);
824 if (!net->mib.udp_stats_in6)
825 return -ENOMEM;
826 net->mib.udplite_stats_in6 = alloc_percpu(struct udp_mib);
827 if (!net->mib.udplite_stats_in6)
828 goto err_udplite_mib;
829 net->mib.ipv6_statistics = alloc_percpu(struct ipstats_mib);
830 if (!net->mib.ipv6_statistics)
831 goto err_ip_mib;
832
833 for_each_possible_cpu(i) {
834 struct ipstats_mib *af_inet6_stats;
835 af_inet6_stats = per_cpu_ptr(net->mib.ipv6_statistics, i);
836 u64_stats_init(&af_inet6_stats->syncp);
837 }
838
839
840 net->mib.icmpv6_statistics = alloc_percpu(struct icmpv6_mib);
841 if (!net->mib.icmpv6_statistics)
842 goto err_icmp_mib;
843 net->mib.icmpv6msg_statistics = kzalloc(sizeof(struct icmpv6msg_mib),
844 GFP_KERNEL);
845 if (!net->mib.icmpv6msg_statistics)
846 goto err_icmpmsg_mib;
847 return 0;
848
849 err_icmpmsg_mib:
850 free_percpu(net->mib.icmpv6_statistics);
851 err_icmp_mib:
852 free_percpu(net->mib.ipv6_statistics);
853 err_ip_mib:
854 free_percpu(net->mib.udplite_stats_in6);
855 err_udplite_mib:
856 free_percpu(net->mib.udp_stats_in6);
857 return -ENOMEM;
858 }
859
ipv6_cleanup_mibs(struct net * net)860 static void ipv6_cleanup_mibs(struct net *net)
861 {
862 free_percpu(net->mib.udp_stats_in6);
863 free_percpu(net->mib.udplite_stats_in6);
864 free_percpu(net->mib.ipv6_statistics);
865 free_percpu(net->mib.icmpv6_statistics);
866 kfree(net->mib.icmpv6msg_statistics);
867 }
868
inet6_net_init(struct net * net)869 static int __net_init inet6_net_init(struct net *net)
870 {
871 int err = 0;
872
873 net->ipv6.sysctl.bindv6only = 0;
874 net->ipv6.sysctl.icmpv6_time = 1*HZ;
875 net->ipv6.sysctl.icmpv6_echo_ignore_all = 0;
876 net->ipv6.sysctl.icmpv6_echo_ignore_multicast = 0;
877 net->ipv6.sysctl.icmpv6_echo_ignore_anycast = 0;
878
879 /* By default, rate limit error messages.
880 * Except for pmtu discovery, it would break it.
881 * proc_do_large_bitmap needs pointer to the bitmap.
882 */
883 bitmap_set(net->ipv6.sysctl.icmpv6_ratemask, 0, ICMPV6_ERRMSG_MAX + 1);
884 bitmap_clear(net->ipv6.sysctl.icmpv6_ratemask, ICMPV6_PKT_TOOBIG, 1);
885 net->ipv6.sysctl.icmpv6_ratemask_ptr = net->ipv6.sysctl.icmpv6_ratemask;
886
887 net->ipv6.sysctl.flowlabel_consistency = 1;
888 net->ipv6.sysctl.auto_flowlabels = IP6_DEFAULT_AUTO_FLOW_LABELS;
889 net->ipv6.sysctl.idgen_retries = 3;
890 net->ipv6.sysctl.idgen_delay = 1 * HZ;
891 net->ipv6.sysctl.flowlabel_state_ranges = 0;
892 net->ipv6.sysctl.max_dst_opts_cnt = IP6_DEFAULT_MAX_DST_OPTS_CNT;
893 net->ipv6.sysctl.max_hbh_opts_cnt = IP6_DEFAULT_MAX_HBH_OPTS_CNT;
894 net->ipv6.sysctl.max_dst_opts_len = IP6_DEFAULT_MAX_DST_OPTS_LEN;
895 net->ipv6.sysctl.max_hbh_opts_len = IP6_DEFAULT_MAX_HBH_OPTS_LEN;
896 atomic_set(&net->ipv6.fib6_sernum, 1);
897
898 err = ipv6_init_mibs(net);
899 if (err)
900 return err;
901 #ifdef CONFIG_PROC_FS
902 err = udp6_proc_init(net);
903 if (err)
904 goto out;
905 err = tcp6_proc_init(net);
906 if (err)
907 goto proc_tcp6_fail;
908 err = ac6_proc_init(net);
909 if (err)
910 goto proc_ac6_fail;
911 #endif
912 return err;
913
914 #ifdef CONFIG_PROC_FS
915 proc_ac6_fail:
916 tcp6_proc_exit(net);
917 proc_tcp6_fail:
918 udp6_proc_exit(net);
919 out:
920 ipv6_cleanup_mibs(net);
921 return err;
922 #endif
923 }
924
inet6_net_exit(struct net * net)925 static void __net_exit inet6_net_exit(struct net *net)
926 {
927 #ifdef CONFIG_PROC_FS
928 udp6_proc_exit(net);
929 tcp6_proc_exit(net);
930 ac6_proc_exit(net);
931 #endif
932 ipv6_cleanup_mibs(net);
933 }
934
935 static struct pernet_operations inet6_net_ops = {
936 .init = inet6_net_init,
937 .exit = inet6_net_exit,
938 };
939
ipv6_route_input(struct sk_buff * skb)940 static int ipv6_route_input(struct sk_buff *skb)
941 {
942 ip6_route_input(skb);
943 return skb_dst(skb)->error;
944 }
945
946 static const struct ipv6_stub ipv6_stub_impl = {
947 .ipv6_sock_mc_join = ipv6_sock_mc_join,
948 .ipv6_sock_mc_drop = ipv6_sock_mc_drop,
949 .ipv6_dst_lookup = ip6_dst_lookup,
950 .ipv6_route_input = ipv6_route_input,
951 .fib6_get_table = fib6_get_table,
952 .fib6_table_lookup = fib6_table_lookup,
953 .fib6_lookup = fib6_lookup,
954 .fib6_select_path = fib6_select_path,
955 .ip6_mtu_from_fib6 = ip6_mtu_from_fib6,
956 .fib6_nh_init = fib6_nh_init,
957 .fib6_nh_release = fib6_nh_release,
958 .fib6_update_sernum = fib6_update_sernum_stub,
959 .fib6_rt_update = fib6_rt_update,
960 .ip6_del_rt = ip6_del_rt,
961 .udpv6_encap_enable = udpv6_encap_enable,
962 .ndisc_send_na = ndisc_send_na,
963 .nd_tbl = &nd_tbl,
964 };
965
966 static const struct ipv6_bpf_stub ipv6_bpf_stub_impl = {
967 .inet6_bind = __inet6_bind,
968 .udp6_lib_lookup = __udp6_lib_lookup,
969 };
970
inet6_init(void)971 static int __init inet6_init(void)
972 {
973 struct list_head *r;
974 int err = 0;
975
976 sock_skb_cb_check_size(sizeof(struct inet6_skb_parm));
977
978 /* Register the socket-side information for inet6_create. */
979 for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
980 INIT_LIST_HEAD(r);
981
982 if (disable_ipv6_mod) {
983 pr_info("Loaded, but administratively disabled, reboot required to enable\n");
984 goto out;
985 }
986
987 err = proto_register(&tcpv6_prot, 1);
988 if (err)
989 goto out;
990
991 err = proto_register(&udpv6_prot, 1);
992 if (err)
993 goto out_unregister_tcp_proto;
994
995 err = proto_register(&udplitev6_prot, 1);
996 if (err)
997 goto out_unregister_udp_proto;
998
999 err = proto_register(&rawv6_prot, 1);
1000 if (err)
1001 goto out_unregister_udplite_proto;
1002
1003 err = proto_register(&pingv6_prot, 1);
1004 if (err)
1005 goto out_unregister_raw_proto;
1006
1007 /* We MUST register RAW sockets before we create the ICMP6,
1008 * IGMP6, or NDISC control sockets.
1009 */
1010 err = rawv6_init();
1011 if (err)
1012 goto out_unregister_ping_proto;
1013
1014 /* Register the family here so that the init calls below will
1015 * be able to create sockets. (?? is this dangerous ??)
1016 */
1017 err = sock_register(&inet6_family_ops);
1018 if (err)
1019 goto out_sock_register_fail;
1020
1021 /*
1022 * ipngwg API draft makes clear that the correct semantics
1023 * for TCP and UDP is to consider one TCP and UDP instance
1024 * in a host available by both INET and INET6 APIs and
1025 * able to communicate via both network protocols.
1026 */
1027
1028 err = register_pernet_subsys(&inet6_net_ops);
1029 if (err)
1030 goto register_pernet_fail;
1031 err = ip6_mr_init();
1032 if (err)
1033 goto ipmr_fail;
1034 err = icmpv6_init();
1035 if (err)
1036 goto icmp_fail;
1037 err = ndisc_init();
1038 if (err)
1039 goto ndisc_fail;
1040 err = igmp6_init();
1041 if (err)
1042 goto igmp_fail;
1043
1044 err = ipv6_netfilter_init();
1045 if (err)
1046 goto netfilter_fail;
1047 /* Create /proc/foo6 entries. */
1048 #ifdef CONFIG_PROC_FS
1049 err = -ENOMEM;
1050 if (raw6_proc_init())
1051 goto proc_raw6_fail;
1052 if (udplite6_proc_init())
1053 goto proc_udplite6_fail;
1054 if (ipv6_misc_proc_init())
1055 goto proc_misc6_fail;
1056 if (if6_proc_init())
1057 goto proc_if6_fail;
1058 #endif
1059 err = ip6_route_init();
1060 if (err)
1061 goto ip6_route_fail;
1062 err = ndisc_late_init();
1063 if (err)
1064 goto ndisc_late_fail;
1065 err = ip6_flowlabel_init();
1066 if (err)
1067 goto ip6_flowlabel_fail;
1068 err = ipv6_anycast_init();
1069 if (err)
1070 goto ipv6_anycast_fail;
1071 err = addrconf_init();
1072 if (err)
1073 goto addrconf_fail;
1074
1075 /* Init v6 extension headers. */
1076 err = ipv6_exthdrs_init();
1077 if (err)
1078 goto ipv6_exthdrs_fail;
1079
1080 err = ipv6_frag_init();
1081 if (err)
1082 goto ipv6_frag_fail;
1083
1084 /* Init v6 transport protocols. */
1085 err = udpv6_init();
1086 if (err)
1087 goto udpv6_fail;
1088
1089 err = udplitev6_init();
1090 if (err)
1091 goto udplitev6_fail;
1092
1093 err = udpv6_offload_init();
1094 if (err)
1095 goto udpv6_offload_fail;
1096
1097 err = tcpv6_init();
1098 if (err)
1099 goto tcpv6_fail;
1100
1101 err = ipv6_packet_init();
1102 if (err)
1103 goto ipv6_packet_fail;
1104
1105 err = pingv6_init();
1106 if (err)
1107 goto pingv6_fail;
1108
1109 err = calipso_init();
1110 if (err)
1111 goto calipso_fail;
1112
1113 err = seg6_init();
1114 if (err)
1115 goto seg6_fail;
1116
1117 err = igmp6_late_init();
1118 if (err)
1119 goto igmp6_late_err;
1120
1121 #ifdef CONFIG_SYSCTL
1122 err = ipv6_sysctl_register();
1123 if (err)
1124 goto sysctl_fail;
1125 #endif
1126
1127 /* ensure that ipv6 stubs are visible only after ipv6 is ready */
1128 wmb();
1129 ipv6_stub = &ipv6_stub_impl;
1130 ipv6_bpf_stub = &ipv6_bpf_stub_impl;
1131 out:
1132 return err;
1133
1134 #ifdef CONFIG_SYSCTL
1135 sysctl_fail:
1136 igmp6_late_cleanup();
1137 #endif
1138 igmp6_late_err:
1139 seg6_exit();
1140 seg6_fail:
1141 calipso_exit();
1142 calipso_fail:
1143 pingv6_exit();
1144 pingv6_fail:
1145 ipv6_packet_cleanup();
1146 ipv6_packet_fail:
1147 tcpv6_exit();
1148 tcpv6_fail:
1149 udpv6_offload_exit();
1150 udpv6_offload_fail:
1151 udplitev6_exit();
1152 udplitev6_fail:
1153 udpv6_exit();
1154 udpv6_fail:
1155 ipv6_frag_exit();
1156 ipv6_frag_fail:
1157 ipv6_exthdrs_exit();
1158 ipv6_exthdrs_fail:
1159 addrconf_cleanup();
1160 addrconf_fail:
1161 ipv6_anycast_cleanup();
1162 ipv6_anycast_fail:
1163 ip6_flowlabel_cleanup();
1164 ip6_flowlabel_fail:
1165 ndisc_late_cleanup();
1166 ndisc_late_fail:
1167 ip6_route_cleanup();
1168 ip6_route_fail:
1169 #ifdef CONFIG_PROC_FS
1170 if6_proc_exit();
1171 proc_if6_fail:
1172 ipv6_misc_proc_exit();
1173 proc_misc6_fail:
1174 udplite6_proc_exit();
1175 proc_udplite6_fail:
1176 raw6_proc_exit();
1177 proc_raw6_fail:
1178 #endif
1179 ipv6_netfilter_fini();
1180 netfilter_fail:
1181 igmp6_cleanup();
1182 igmp_fail:
1183 ndisc_cleanup();
1184 ndisc_fail:
1185 icmpv6_cleanup();
1186 icmp_fail:
1187 ip6_mr_cleanup();
1188 ipmr_fail:
1189 unregister_pernet_subsys(&inet6_net_ops);
1190 register_pernet_fail:
1191 sock_unregister(PF_INET6);
1192 rtnl_unregister_all(PF_INET6);
1193 out_sock_register_fail:
1194 rawv6_exit();
1195 out_unregister_ping_proto:
1196 proto_unregister(&pingv6_prot);
1197 out_unregister_raw_proto:
1198 proto_unregister(&rawv6_prot);
1199 out_unregister_udplite_proto:
1200 proto_unregister(&udplitev6_prot);
1201 out_unregister_udp_proto:
1202 proto_unregister(&udpv6_prot);
1203 out_unregister_tcp_proto:
1204 proto_unregister(&tcpv6_prot);
1205 goto out;
1206 }
1207 module_init(inet6_init);
1208
1209 MODULE_ALIAS_NETPROTO(PF_INET6);
1210
