1 /* 2 * IPv6 BSD socket options interface 3 * Linux INET6 implementation 4 * 5 * Authors: 6 * Pedro Roque <roque@di.fc.ul.pt> 7 * 8 * Based on linux/net/ipv4/ip_sockglue.c 9 * 10 * $Id: ipv6_sockglue.c,v 1.41 2002/02/01 22:01:04 davem Exp $ 11 * 12 * This program is free software; you can redistribute it and/or 13 * modify it under the terms of the GNU General Public License 14 * as published by the Free Software Foundation; either version 15 * 2 of the License, or (at your option) any later version. 16 * 17 * FIXME: Make the setsockopt code POSIX compliant: That is 18 * 19 * o Return -EINVAL for setsockopt of short lengths 20 * o Truncate getsockopt returns 21 * o Return an optlen of the truncated length if need be 22 * 23 * Changes: 24 * David L Stevens <dlstevens@us.ibm.com>: 25 * - added multicast source filtering API for MLDv2 26 */ 27 28 #include <linux/module.h> 29 #include <linux/config.h> 30 #include <linux/errno.h> 31 #include <linux/types.h> 32 #include <linux/socket.h> 33 #include <linux/sockios.h> 34 #include <linux/sched.h> 35 #include <linux/net.h> 36 #include <linux/in6.h> 37 #include <linux/netdevice.h> 38 #include <linux/if_arp.h> 39 #include <linux/init.h> 40 #include <linux/sysctl.h> 41 #include <linux/netfilter.h> 42 43 #include <net/sock.h> 44 #include <net/snmp.h> 45 #include <net/ipv6.h> 46 #include <net/ndisc.h> 47 #include <net/protocol.h> 48 #include <net/transp_v6.h> 49 #include <net/ip6_route.h> 50 #include <net/addrconf.h> 51 #include <net/inet_common.h> 52 #include <net/tcp.h> 53 #include <net/udp.h> 54 #include <net/xfrm.h> 55 56 #include <asm/uaccess.h> 57 58 DEFINE_SNMP_STAT(struct ipstats_mib, ipv6_statistics); 59 60 static struct packet_type ipv6_packet_type = { 61 .type = __constant_htons(ETH_P_IPV6), 62 .func = ipv6_rcv, 63 }; 64 65 struct ip6_ra_chain *ip6_ra_chain; 66 DEFINE_RWLOCK(ip6_ra_lock); 67 68 int ip6_ra_control(struct sock *sk, int sel, void (*destructor)(struct sock *)) 69 { 70 struct ip6_ra_chain *ra, *new_ra, **rap; 71 72 /* RA packet may be delivered ONLY to IPPROTO_RAW socket */ 73 if (sk->sk_type != SOCK_RAW || inet_sk(sk)->num != IPPROTO_RAW) 74 return -EINVAL; 75 76 new_ra = (sel>=0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL; 77 78 write_lock_bh(&ip6_ra_lock); 79 for (rap = &ip6_ra_chain; (ra=*rap) != NULL; rap = &ra->next) { 80 if (ra->sk == sk) { 81 if (sel>=0) { 82 write_unlock_bh(&ip6_ra_lock); 83 if (new_ra) 84 kfree(new_ra); 85 return -EADDRINUSE; 86 } 87 88 *rap = ra->next; 89 write_unlock_bh(&ip6_ra_lock); 90 91 if (ra->destructor) 92 ra->destructor(sk); 93 sock_put(sk); 94 kfree(ra); 95 return 0; 96 } 97 } 98 if (new_ra == NULL) { 99 write_unlock_bh(&ip6_ra_lock); 100 return -ENOBUFS; 101 } 102 new_ra->sk = sk; 103 new_ra->sel = sel; 104 new_ra->destructor = destructor; 105 new_ra->next = ra; 106 *rap = new_ra; 107 sock_hold(sk); 108 write_unlock_bh(&ip6_ra_lock); 109 return 0; 110 } 111 112 int ipv6_setsockopt(struct sock *sk, int level, int optname, 113 char __user *optval, int optlen) 114 { 115 struct ipv6_pinfo *np = inet6_sk(sk); 116 int val, valbool; 117 int retv = -ENOPROTOOPT; 118 119 if (level == SOL_IP && sk->sk_type != SOCK_RAW) 120 return udp_prot.setsockopt(sk, level, optname, optval, optlen); 121 122 if(level!=SOL_IPV6) 123 goto out; 124 125 if (optval == NULL) 126 val=0; 127 else if (get_user(val, (int __user *) optval)) 128 return -EFAULT; 129 130 valbool = (val!=0); 131 132 lock_sock(sk); 133 134 switch (optname) { 135 136 case IPV6_ADDRFORM: 137 if (val == PF_INET) { 138 struct ipv6_txoptions *opt; 139 struct sk_buff *pktopt; 140 141 if (sk->sk_protocol != IPPROTO_UDP && 142 sk->sk_protocol != IPPROTO_TCP) 143 break; 144 145 if (sk->sk_state != TCP_ESTABLISHED) { 146 retv = -ENOTCONN; 147 break; 148 } 149 150 if (ipv6_only_sock(sk) || 151 !(ipv6_addr_type(&np->daddr) & IPV6_ADDR_MAPPED)) { 152 retv = -EADDRNOTAVAIL; 153 break; 154 } 155 156 fl6_free_socklist(sk); 157 ipv6_sock_mc_close(sk); 158 159 /* 160 * Sock is moving from IPv6 to IPv4 (sk_prot), so 161 * remove it from the refcnt debug socks count in the 162 * original family... 163 */ 164 sk_refcnt_debug_dec(sk); 165 166 if (sk->sk_protocol == IPPROTO_TCP) { 167 struct tcp_sock *tp = tcp_sk(sk); 168 169 local_bh_disable(); 170 sock_prot_dec_use(sk->sk_prot); 171 sock_prot_inc_use(&tcp_prot); 172 local_bh_enable(); 173 sk->sk_prot = &tcp_prot; 174 tp->af_specific = &ipv4_specific; 175 sk->sk_socket->ops = &inet_stream_ops; 176 sk->sk_family = PF_INET; 177 tcp_sync_mss(sk, tp->pmtu_cookie); 178 } else { 179 local_bh_disable(); 180 sock_prot_dec_use(sk->sk_prot); 181 sock_prot_inc_use(&udp_prot); 182 local_bh_enable(); 183 sk->sk_prot = &udp_prot; 184 sk->sk_socket->ops = &inet_dgram_ops; 185 sk->sk_family = PF_INET; 186 } 187 opt = xchg(&np->opt, NULL); 188 if (opt) 189 sock_kfree_s(sk, opt, opt->tot_len); 190 pktopt = xchg(&np->pktoptions, NULL); 191 if (pktopt) 192 kfree_skb(pktopt); 193 194 sk->sk_destruct = inet_sock_destruct; 195 /* 196 * ... and add it to the refcnt debug socks count 197 * in the new family. -acme 198 */ 199 sk_refcnt_debug_inc(sk); 200 module_put(THIS_MODULE); 201 retv = 0; 202 break; 203 } 204 goto e_inval; 205 206 case IPV6_V6ONLY: 207 if (inet_sk(sk)->num) 208 goto e_inval; 209 np->ipv6only = valbool; 210 retv = 0; 211 break; 212 213 case IPV6_PKTINFO: 214 np->rxopt.bits.rxinfo = valbool; 215 retv = 0; 216 break; 217 218 case IPV6_HOPLIMIT: 219 np->rxopt.bits.rxhlim = valbool; 220 retv = 0; 221 break; 222 223 case IPV6_RTHDR: 224 if (val < 0 || val > 2) 225 goto e_inval; 226 np->rxopt.bits.srcrt = val; 227 retv = 0; 228 break; 229 230 case IPV6_HOPOPTS: 231 np->rxopt.bits.hopopts = valbool; 232 retv = 0; 233 break; 234 235 case IPV6_DSTOPTS: 236 np->rxopt.bits.dstopts = valbool; 237 retv = 0; 238 break; 239 240 case IPV6_FLOWINFO: 241 np->rxopt.bits.rxflow = valbool; 242 retv = 0; 243 break; 244 245 case IPV6_PKTOPTIONS: 246 { 247 struct ipv6_txoptions *opt = NULL; 248 struct msghdr msg; 249 struct flowi fl; 250 int junk; 251 252 fl.fl6_flowlabel = 0; 253 fl.oif = sk->sk_bound_dev_if; 254 255 if (optlen == 0) 256 goto update; 257 258 /* 1K is probably excessive 259 * 1K is surely not enough, 2K per standard header is 16K. 260 */ 261 retv = -EINVAL; 262 if (optlen > 64*1024) 263 break; 264 265 opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL); 266 retv = -ENOBUFS; 267 if (opt == NULL) 268 break; 269 270 memset(opt, 0, sizeof(*opt)); 271 opt->tot_len = sizeof(*opt) + optlen; 272 retv = -EFAULT; 273 if (copy_from_user(opt+1, optval, optlen)) 274 goto done; 275 276 msg.msg_controllen = optlen; 277 msg.msg_control = (void*)(opt+1); 278 279 retv = datagram_send_ctl(&msg, &fl, opt, &junk); 280 if (retv) 281 goto done; 282 update: 283 retv = 0; 284 if (sk->sk_type == SOCK_STREAM) { 285 if (opt) { 286 struct tcp_sock *tp = tcp_sk(sk); 287 if (!((1 << sk->sk_state) & 288 (TCPF_LISTEN | TCPF_CLOSE)) 289 && inet_sk(sk)->daddr != LOOPBACK4_IPV6) { 290 tp->ext_header_len = opt->opt_flen + opt->opt_nflen; 291 tcp_sync_mss(sk, tp->pmtu_cookie); 292 } 293 } 294 opt = xchg(&np->opt, opt); 295 sk_dst_reset(sk); 296 } else { 297 write_lock(&sk->sk_dst_lock); 298 opt = xchg(&np->opt, opt); 299 write_unlock(&sk->sk_dst_lock); 300 sk_dst_reset(sk); 301 } 302 303 done: 304 if (opt) 305 sock_kfree_s(sk, opt, opt->tot_len); 306 break; 307 } 308 case IPV6_UNICAST_HOPS: 309 if (val > 255 || val < -1) 310 goto e_inval; 311 np->hop_limit = val; 312 retv = 0; 313 break; 314 315 case IPV6_MULTICAST_HOPS: 316 if (sk->sk_type == SOCK_STREAM) 317 goto e_inval; 318 if (val > 255 || val < -1) 319 goto e_inval; 320 np->mcast_hops = val; 321 retv = 0; 322 break; 323 324 case IPV6_MULTICAST_LOOP: 325 np->mc_loop = valbool; 326 retv = 0; 327 break; 328 329 case IPV6_MULTICAST_IF: 330 if (sk->sk_type == SOCK_STREAM) 331 goto e_inval; 332 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != val) 333 goto e_inval; 334 335 if (__dev_get_by_index(val) == NULL) { 336 retv = -ENODEV; 337 break; 338 } 339 np->mcast_oif = val; 340 retv = 0; 341 break; 342 case IPV6_ADD_MEMBERSHIP: 343 case IPV6_DROP_MEMBERSHIP: 344 { 345 struct ipv6_mreq mreq; 346 347 retv = -EFAULT; 348 if (copy_from_user(&mreq, optval, sizeof(struct ipv6_mreq))) 349 break; 350 351 if (optname == IPV6_ADD_MEMBERSHIP) 352 retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr); 353 else 354 retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr); 355 break; 356 } 357 case IPV6_JOIN_ANYCAST: 358 case IPV6_LEAVE_ANYCAST: 359 { 360 struct ipv6_mreq mreq; 361 362 if (optlen != sizeof(struct ipv6_mreq)) 363 goto e_inval; 364 365 retv = -EFAULT; 366 if (copy_from_user(&mreq, optval, sizeof(struct ipv6_mreq))) 367 break; 368 369 if (optname == IPV6_JOIN_ANYCAST) 370 retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr); 371 else 372 retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr); 373 break; 374 } 375 case MCAST_JOIN_GROUP: 376 case MCAST_LEAVE_GROUP: 377 { 378 struct group_req greq; 379 struct sockaddr_in6 *psin6; 380 381 retv = -EFAULT; 382 if (copy_from_user(&greq, optval, sizeof(struct group_req))) 383 break; 384 if (greq.gr_group.ss_family != AF_INET6) { 385 retv = -EADDRNOTAVAIL; 386 break; 387 } 388 psin6 = (struct sockaddr_in6 *)&greq.gr_group; 389 if (optname == MCAST_JOIN_GROUP) 390 retv = ipv6_sock_mc_join(sk, greq.gr_interface, 391 &psin6->sin6_addr); 392 else 393 retv = ipv6_sock_mc_drop(sk, greq.gr_interface, 394 &psin6->sin6_addr); 395 break; 396 } 397 case MCAST_JOIN_SOURCE_GROUP: 398 case MCAST_LEAVE_SOURCE_GROUP: 399 case MCAST_BLOCK_SOURCE: 400 case MCAST_UNBLOCK_SOURCE: 401 { 402 struct group_source_req greqs; 403 int omode, add; 404 405 if (optlen != sizeof(struct group_source_req)) 406 goto e_inval; 407 if (copy_from_user(&greqs, optval, sizeof(greqs))) { 408 retv = -EFAULT; 409 break; 410 } 411 if (greqs.gsr_group.ss_family != AF_INET6 || 412 greqs.gsr_source.ss_family != AF_INET6) { 413 retv = -EADDRNOTAVAIL; 414 break; 415 } 416 if (optname == MCAST_BLOCK_SOURCE) { 417 omode = MCAST_EXCLUDE; 418 add = 1; 419 } else if (optname == MCAST_UNBLOCK_SOURCE) { 420 omode = MCAST_EXCLUDE; 421 add = 0; 422 } else if (optname == MCAST_JOIN_SOURCE_GROUP) { 423 struct sockaddr_in6 *psin6; 424 425 psin6 = (struct sockaddr_in6 *)&greqs.gsr_group; 426 retv = ipv6_sock_mc_join(sk, greqs.gsr_interface, 427 &psin6->sin6_addr); 428 /* prior join w/ different source is ok */ 429 if (retv && retv != -EADDRINUSE) 430 break; 431 omode = MCAST_INCLUDE; 432 add = 1; 433 } else /* MCAST_LEAVE_SOURCE_GROUP */ { 434 omode = MCAST_INCLUDE; 435 add = 0; 436 } 437 retv = ip6_mc_source(add, omode, sk, &greqs); 438 break; 439 } 440 case MCAST_MSFILTER: 441 { 442 extern int sysctl_mld_max_msf; 443 struct group_filter *gsf; 444 445 if (optlen < GROUP_FILTER_SIZE(0)) 446 goto e_inval; 447 if (optlen > sysctl_optmem_max) { 448 retv = -ENOBUFS; 449 break; 450 } 451 gsf = (struct group_filter *)kmalloc(optlen,GFP_KERNEL); 452 if (gsf == 0) { 453 retv = -ENOBUFS; 454 break; 455 } 456 retv = -EFAULT; 457 if (copy_from_user(gsf, optval, optlen)) { 458 kfree(gsf); 459 break; 460 } 461 /* numsrc >= (4G-140)/128 overflow in 32 bits */ 462 if (gsf->gf_numsrc >= 0x1ffffffU || 463 gsf->gf_numsrc > sysctl_mld_max_msf) { 464 kfree(gsf); 465 retv = -ENOBUFS; 466 break; 467 } 468 if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) { 469 kfree(gsf); 470 retv = -EINVAL; 471 break; 472 } 473 retv = ip6_mc_msfilter(sk, gsf); 474 kfree(gsf); 475 476 break; 477 } 478 case IPV6_ROUTER_ALERT: 479 retv = ip6_ra_control(sk, val, NULL); 480 break; 481 case IPV6_MTU_DISCOVER: 482 if (val<0 || val>2) 483 goto e_inval; 484 np->pmtudisc = val; 485 retv = 0; 486 break; 487 case IPV6_MTU: 488 if (val && val < IPV6_MIN_MTU) 489 goto e_inval; 490 np->frag_size = val; 491 retv = 0; 492 break; 493 case IPV6_RECVERR: 494 np->recverr = valbool; 495 if (!val) 496 skb_queue_purge(&sk->sk_error_queue); 497 retv = 0; 498 break; 499 case IPV6_FLOWINFO_SEND: 500 np->sndflow = valbool; 501 retv = 0; 502 break; 503 case IPV6_FLOWLABEL_MGR: 504 retv = ipv6_flowlabel_opt(sk, optval, optlen); 505 break; 506 case IPV6_IPSEC_POLICY: 507 case IPV6_XFRM_POLICY: 508 retv = -EPERM; 509 if (!capable(CAP_NET_ADMIN)) 510 break; 511 retv = xfrm_user_policy(sk, optname, optval, optlen); 512 break; 513 514 #ifdef CONFIG_NETFILTER 515 default: 516 retv = nf_setsockopt(sk, PF_INET6, optname, optval, 517 optlen); 518 break; 519 #endif 520 521 } 522 release_sock(sk); 523 524 out: 525 return retv; 526 527 e_inval: 528 release_sock(sk); 529 return -EINVAL; 530 } 531 532 int ipv6_getsockopt(struct sock *sk, int level, int optname, 533 char __user *optval, int __user *optlen) 534 { 535 struct ipv6_pinfo *np = inet6_sk(sk); 536 int len; 537 int val; 538 539 if (level == SOL_IP && sk->sk_type != SOCK_RAW) 540 return udp_prot.getsockopt(sk, level, optname, optval, optlen); 541 if(level!=SOL_IPV6) 542 return -ENOPROTOOPT; 543 if (get_user(len, optlen)) 544 return -EFAULT; 545 switch (optname) { 546 case IPV6_ADDRFORM: 547 if (sk->sk_protocol != IPPROTO_UDP && 548 sk->sk_protocol != IPPROTO_TCP) 549 return -EINVAL; 550 if (sk->sk_state != TCP_ESTABLISHED) 551 return -ENOTCONN; 552 val = sk->sk_family; 553 break; 554 case MCAST_MSFILTER: 555 { 556 struct group_filter gsf; 557 int err; 558 559 if (len < GROUP_FILTER_SIZE(0)) 560 return -EINVAL; 561 if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) 562 return -EFAULT; 563 lock_sock(sk); 564 err = ip6_mc_msfget(sk, &gsf, 565 (struct group_filter __user *)optval, optlen); 566 release_sock(sk); 567 return err; 568 } 569 570 case IPV6_PKTOPTIONS: 571 { 572 struct msghdr msg; 573 struct sk_buff *skb; 574 575 if (sk->sk_type != SOCK_STREAM) 576 return -ENOPROTOOPT; 577 578 msg.msg_control = optval; 579 msg.msg_controllen = len; 580 msg.msg_flags = 0; 581 582 lock_sock(sk); 583 skb = np->pktoptions; 584 if (skb) 585 atomic_inc(&skb->users); 586 release_sock(sk); 587 588 if (skb) { 589 int err = datagram_recv_ctl(sk, &msg, skb); 590 kfree_skb(skb); 591 if (err) 592 return err; 593 } else { 594 if (np->rxopt.bits.rxinfo) { 595 struct in6_pktinfo src_info; 596 src_info.ipi6_ifindex = np->mcast_oif; 597 ipv6_addr_copy(&src_info.ipi6_addr, &np->daddr); 598 put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info); 599 } 600 if (np->rxopt.bits.rxhlim) { 601 int hlim = np->mcast_hops; 602 put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim); 603 } 604 } 605 len -= msg.msg_controllen; 606 return put_user(len, optlen); 607 } 608 case IPV6_MTU: 609 { 610 struct dst_entry *dst; 611 val = 0; 612 lock_sock(sk); 613 dst = sk_dst_get(sk); 614 if (dst) { 615 val = dst_mtu(dst); 616 dst_release(dst); 617 } 618 release_sock(sk); 619 if (!val) 620 return -ENOTCONN; 621 break; 622 } 623 624 case IPV6_V6ONLY: 625 val = np->ipv6only; 626 break; 627 628 case IPV6_PKTINFO: 629 val = np->rxopt.bits.rxinfo; 630 break; 631 632 case IPV6_HOPLIMIT: 633 val = np->rxopt.bits.rxhlim; 634 break; 635 636 case IPV6_RTHDR: 637 val = np->rxopt.bits.srcrt; 638 break; 639 640 case IPV6_HOPOPTS: 641 val = np->rxopt.bits.hopopts; 642 break; 643 644 case IPV6_DSTOPTS: 645 val = np->rxopt.bits.dstopts; 646 break; 647 648 case IPV6_FLOWINFO: 649 val = np->rxopt.bits.rxflow; 650 break; 651 652 case IPV6_UNICAST_HOPS: 653 val = np->hop_limit; 654 break; 655 656 case IPV6_MULTICAST_HOPS: 657 val = np->mcast_hops; 658 break; 659 660 case IPV6_MULTICAST_LOOP: 661 val = np->mc_loop; 662 break; 663 664 case IPV6_MULTICAST_IF: 665 val = np->mcast_oif; 666 break; 667 668 case IPV6_MTU_DISCOVER: 669 val = np->pmtudisc; 670 break; 671 672 case IPV6_RECVERR: 673 val = np->recverr; 674 break; 675 676 case IPV6_FLOWINFO_SEND: 677 val = np->sndflow; 678 break; 679 680 default: 681 #ifdef CONFIG_NETFILTER 682 lock_sock(sk); 683 val = nf_getsockopt(sk, PF_INET6, optname, optval, 684 &len); 685 release_sock(sk); 686 if (val >= 0) 687 val = put_user(len, optlen); 688 return val; 689 #else 690 return -EINVAL; 691 #endif 692 } 693 len = min_t(unsigned int, sizeof(int), len); 694 if(put_user(len, optlen)) 695 return -EFAULT; 696 if(copy_to_user(optval,&val,len)) 697 return -EFAULT; 698 return 0; 699 } 700 701 void __init ipv6_packet_init(void) 702 { 703 dev_add_pack(&ipv6_packet_type); 704 } 705 706 void ipv6_packet_cleanup(void) 707 { 708 dev_remove_pack(&ipv6_packet_type); 709 } 710