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 extern int ip6_mc_source(int add, int omode, struct sock *sk, 113 struct group_source_req *pgsr); 114 extern int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf); 115 extern int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, 116 struct group_filter __user *optval, int __user *optlen); 117 118 119 int ipv6_setsockopt(struct sock *sk, int level, int optname, 120 char __user *optval, int optlen) 121 { 122 struct ipv6_pinfo *np = inet6_sk(sk); 123 int val, valbool; 124 int retv = -ENOPROTOOPT; 125 126 if (level == SOL_IP && sk->sk_type != SOCK_RAW) 127 return udp_prot.setsockopt(sk, level, optname, optval, optlen); 128 129 if(level!=SOL_IPV6) 130 goto out; 131 132 if (optval == NULL) 133 val=0; 134 else if (get_user(val, (int __user *) optval)) 135 return -EFAULT; 136 137 valbool = (val!=0); 138 139 lock_sock(sk); 140 141 switch (optname) { 142 143 case IPV6_ADDRFORM: 144 if (val == PF_INET) { 145 struct ipv6_txoptions *opt; 146 struct sk_buff *pktopt; 147 148 if (sk->sk_protocol != IPPROTO_UDP && 149 sk->sk_protocol != IPPROTO_TCP) 150 break; 151 152 if (sk->sk_state != TCP_ESTABLISHED) { 153 retv = -ENOTCONN; 154 break; 155 } 156 157 if (ipv6_only_sock(sk) || 158 !(ipv6_addr_type(&np->daddr) & IPV6_ADDR_MAPPED)) { 159 retv = -EADDRNOTAVAIL; 160 break; 161 } 162 163 fl6_free_socklist(sk); 164 ipv6_sock_mc_close(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 #ifdef INET_REFCNT_DEBUG 196 atomic_dec(&inet6_sock_nr); 197 #endif 198 module_put(THIS_MODULE); 199 retv = 0; 200 break; 201 } 202 goto e_inval; 203 204 case IPV6_V6ONLY: 205 if (inet_sk(sk)->num) 206 goto e_inval; 207 np->ipv6only = valbool; 208 retv = 0; 209 break; 210 211 case IPV6_PKTINFO: 212 np->rxopt.bits.rxinfo = valbool; 213 retv = 0; 214 break; 215 216 case IPV6_HOPLIMIT: 217 np->rxopt.bits.rxhlim = valbool; 218 retv = 0; 219 break; 220 221 case IPV6_RTHDR: 222 if (val < 0 || val > 2) 223 goto e_inval; 224 np->rxopt.bits.srcrt = val; 225 retv = 0; 226 break; 227 228 case IPV6_HOPOPTS: 229 np->rxopt.bits.hopopts = valbool; 230 retv = 0; 231 break; 232 233 case IPV6_DSTOPTS: 234 np->rxopt.bits.dstopts = valbool; 235 retv = 0; 236 break; 237 238 case IPV6_FLOWINFO: 239 np->rxopt.bits.rxflow = valbool; 240 retv = 0; 241 break; 242 243 case IPV6_PKTOPTIONS: 244 { 245 struct ipv6_txoptions *opt = NULL; 246 struct msghdr msg; 247 struct flowi fl; 248 int junk; 249 250 fl.fl6_flowlabel = 0; 251 fl.oif = sk->sk_bound_dev_if; 252 253 if (optlen == 0) 254 goto update; 255 256 /* 1K is probably excessive 257 * 1K is surely not enough, 2K per standard header is 16K. 258 */ 259 retv = -EINVAL; 260 if (optlen > 64*1024) 261 break; 262 263 opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL); 264 retv = -ENOBUFS; 265 if (opt == NULL) 266 break; 267 268 memset(opt, 0, sizeof(*opt)); 269 opt->tot_len = sizeof(*opt) + optlen; 270 retv = -EFAULT; 271 if (copy_from_user(opt+1, optval, optlen)) 272 goto done; 273 274 msg.msg_controllen = optlen; 275 msg.msg_control = (void*)(opt+1); 276 277 retv = datagram_send_ctl(&msg, &fl, opt, &junk); 278 if (retv) 279 goto done; 280 update: 281 retv = 0; 282 if (sk->sk_type == SOCK_STREAM) { 283 if (opt) { 284 struct tcp_sock *tp = tcp_sk(sk); 285 if (!((1 << sk->sk_state) & 286 (TCPF_LISTEN | TCPF_CLOSE)) 287 && inet_sk(sk)->daddr != LOOPBACK4_IPV6) { 288 tp->ext_header_len = opt->opt_flen + opt->opt_nflen; 289 tcp_sync_mss(sk, tp->pmtu_cookie); 290 } 291 } 292 opt = xchg(&np->opt, opt); 293 sk_dst_reset(sk); 294 } else { 295 write_lock(&sk->sk_dst_lock); 296 opt = xchg(&np->opt, opt); 297 write_unlock(&sk->sk_dst_lock); 298 sk_dst_reset(sk); 299 } 300 301 done: 302 if (opt) 303 sock_kfree_s(sk, opt, opt->tot_len); 304 break; 305 } 306 case IPV6_UNICAST_HOPS: 307 if (val > 255 || val < -1) 308 goto e_inval; 309 np->hop_limit = val; 310 retv = 0; 311 break; 312 313 case IPV6_MULTICAST_HOPS: 314 if (sk->sk_type == SOCK_STREAM) 315 goto e_inval; 316 if (val > 255 || val < -1) 317 goto e_inval; 318 np->mcast_hops = val; 319 retv = 0; 320 break; 321 322 case IPV6_MULTICAST_LOOP: 323 np->mc_loop = valbool; 324 retv = 0; 325 break; 326 327 case IPV6_MULTICAST_IF: 328 if (sk->sk_type == SOCK_STREAM) 329 goto e_inval; 330 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != val) 331 goto e_inval; 332 333 if (__dev_get_by_index(val) == NULL) { 334 retv = -ENODEV; 335 break; 336 } 337 np->mcast_oif = val; 338 retv = 0; 339 break; 340 case IPV6_ADD_MEMBERSHIP: 341 case IPV6_DROP_MEMBERSHIP: 342 { 343 struct ipv6_mreq mreq; 344 345 retv = -EFAULT; 346 if (copy_from_user(&mreq, optval, sizeof(struct ipv6_mreq))) 347 break; 348 349 if (optname == IPV6_ADD_MEMBERSHIP) 350 retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr); 351 else 352 retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr); 353 break; 354 } 355 case IPV6_JOIN_ANYCAST: 356 case IPV6_LEAVE_ANYCAST: 357 { 358 struct ipv6_mreq mreq; 359 360 if (optlen != sizeof(struct ipv6_mreq)) 361 goto e_inval; 362 363 retv = -EFAULT; 364 if (copy_from_user(&mreq, optval, sizeof(struct ipv6_mreq))) 365 break; 366 367 if (optname == IPV6_JOIN_ANYCAST) 368 retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr); 369 else 370 retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr); 371 break; 372 } 373 case MCAST_JOIN_GROUP: 374 case MCAST_LEAVE_GROUP: 375 { 376 struct group_req greq; 377 struct sockaddr_in6 *psin6; 378 379 retv = -EFAULT; 380 if (copy_from_user(&greq, optval, sizeof(struct group_req))) 381 break; 382 if (greq.gr_group.ss_family != AF_INET6) { 383 retv = -EADDRNOTAVAIL; 384 break; 385 } 386 psin6 = (struct sockaddr_in6 *)&greq.gr_group; 387 if (optname == MCAST_JOIN_GROUP) 388 retv = ipv6_sock_mc_join(sk, greq.gr_interface, 389 &psin6->sin6_addr); 390 else 391 retv = ipv6_sock_mc_drop(sk, greq.gr_interface, 392 &psin6->sin6_addr); 393 break; 394 } 395 case MCAST_JOIN_SOURCE_GROUP: 396 case MCAST_LEAVE_SOURCE_GROUP: 397 case MCAST_BLOCK_SOURCE: 398 case MCAST_UNBLOCK_SOURCE: 399 { 400 struct group_source_req greqs; 401 int omode, add; 402 403 if (optlen != sizeof(struct group_source_req)) 404 goto e_inval; 405 if (copy_from_user(&greqs, optval, sizeof(greqs))) { 406 retv = -EFAULT; 407 break; 408 } 409 if (greqs.gsr_group.ss_family != AF_INET6 || 410 greqs.gsr_source.ss_family != AF_INET6) { 411 retv = -EADDRNOTAVAIL; 412 break; 413 } 414 if (optname == MCAST_BLOCK_SOURCE) { 415 omode = MCAST_EXCLUDE; 416 add = 1; 417 } else if (optname == MCAST_UNBLOCK_SOURCE) { 418 omode = MCAST_EXCLUDE; 419 add = 0; 420 } else if (optname == MCAST_JOIN_SOURCE_GROUP) { 421 struct sockaddr_in6 *psin6; 422 423 psin6 = (struct sockaddr_in6 *)&greqs.gsr_group; 424 retv = ipv6_sock_mc_join(sk, greqs.gsr_interface, 425 &psin6->sin6_addr); 426 /* prior join w/ different source is ok */ 427 if (retv && retv != -EADDRINUSE) 428 break; 429 omode = MCAST_INCLUDE; 430 add = 1; 431 } else /* MCAST_LEAVE_SOURCE_GROUP */ { 432 omode = MCAST_INCLUDE; 433 add = 0; 434 } 435 retv = ip6_mc_source(add, omode, sk, &greqs); 436 break; 437 } 438 case MCAST_MSFILTER: 439 { 440 extern int sysctl_optmem_max; 441 extern int sysctl_mld_max_msf; 442 struct group_filter *gsf; 443 444 if (optlen < GROUP_FILTER_SIZE(0)) 445 goto e_inval; 446 if (optlen > sysctl_optmem_max) { 447 retv = -ENOBUFS; 448 break; 449 } 450 gsf = (struct group_filter *)kmalloc(optlen,GFP_KERNEL); 451 if (gsf == 0) { 452 retv = -ENOBUFS; 453 break; 454 } 455 retv = -EFAULT; 456 if (copy_from_user(gsf, optval, optlen)) { 457 kfree(gsf); 458 break; 459 } 460 /* numsrc >= (4G-140)/128 overflow in 32 bits */ 461 if (gsf->gf_numsrc >= 0x1ffffffU || 462 gsf->gf_numsrc > sysctl_mld_max_msf) { 463 kfree(gsf); 464 retv = -ENOBUFS; 465 break; 466 } 467 if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) { 468 kfree(gsf); 469 retv = -EINVAL; 470 break; 471 } 472 retv = ip6_mc_msfilter(sk, gsf); 473 kfree(gsf); 474 475 break; 476 } 477 case IPV6_ROUTER_ALERT: 478 retv = ip6_ra_control(sk, val, NULL); 479 break; 480 case IPV6_MTU_DISCOVER: 481 if (val<0 || val>2) 482 goto e_inval; 483 np->pmtudisc = val; 484 retv = 0; 485 break; 486 case IPV6_MTU: 487 if (val && val < IPV6_MIN_MTU) 488 goto e_inval; 489 np->frag_size = val; 490 retv = 0; 491 break; 492 case IPV6_RECVERR: 493 np->recverr = valbool; 494 if (!val) 495 skb_queue_purge(&sk->sk_error_queue); 496 retv = 0; 497 break; 498 case IPV6_FLOWINFO_SEND: 499 np->sndflow = valbool; 500 retv = 0; 501 break; 502 case IPV6_FLOWLABEL_MGR: 503 retv = ipv6_flowlabel_opt(sk, optval, optlen); 504 break; 505 case IPV6_IPSEC_POLICY: 506 case IPV6_XFRM_POLICY: 507 retv = xfrm_user_policy(sk, optname, optval, optlen); 508 break; 509 510 #ifdef CONFIG_NETFILTER 511 default: 512 retv = nf_setsockopt(sk, PF_INET6, optname, optval, 513 optlen); 514 break; 515 #endif 516 517 } 518 release_sock(sk); 519 520 out: 521 return retv; 522 523 e_inval: 524 release_sock(sk); 525 return -EINVAL; 526 } 527 528 int ipv6_getsockopt(struct sock *sk, int level, int optname, 529 char __user *optval, int __user *optlen) 530 { 531 struct ipv6_pinfo *np = inet6_sk(sk); 532 int len; 533 int val; 534 535 if (level == SOL_IP && sk->sk_type != SOCK_RAW) 536 return udp_prot.getsockopt(sk, level, optname, optval, optlen); 537 if(level!=SOL_IPV6) 538 return -ENOPROTOOPT; 539 if (get_user(len, optlen)) 540 return -EFAULT; 541 switch (optname) { 542 case IPV6_ADDRFORM: 543 if (sk->sk_protocol != IPPROTO_UDP && 544 sk->sk_protocol != IPPROTO_TCP) 545 return -EINVAL; 546 if (sk->sk_state != TCP_ESTABLISHED) 547 return -ENOTCONN; 548 val = sk->sk_family; 549 break; 550 case MCAST_MSFILTER: 551 { 552 struct group_filter gsf; 553 int err; 554 555 if (len < GROUP_FILTER_SIZE(0)) 556 return -EINVAL; 557 if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) 558 return -EFAULT; 559 lock_sock(sk); 560 err = ip6_mc_msfget(sk, &gsf, 561 (struct group_filter __user *)optval, optlen); 562 release_sock(sk); 563 return err; 564 } 565 566 case IPV6_PKTOPTIONS: 567 { 568 struct msghdr msg; 569 struct sk_buff *skb; 570 571 if (sk->sk_type != SOCK_STREAM) 572 return -ENOPROTOOPT; 573 574 msg.msg_control = optval; 575 msg.msg_controllen = len; 576 msg.msg_flags = 0; 577 578 lock_sock(sk); 579 skb = np->pktoptions; 580 if (skb) 581 atomic_inc(&skb->users); 582 release_sock(sk); 583 584 if (skb) { 585 int err = datagram_recv_ctl(sk, &msg, skb); 586 kfree_skb(skb); 587 if (err) 588 return err; 589 } else { 590 if (np->rxopt.bits.rxinfo) { 591 struct in6_pktinfo src_info; 592 src_info.ipi6_ifindex = np->mcast_oif; 593 ipv6_addr_copy(&src_info.ipi6_addr, &np->daddr); 594 put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info); 595 } 596 if (np->rxopt.bits.rxhlim) { 597 int hlim = np->mcast_hops; 598 put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim); 599 } 600 } 601 len -= msg.msg_controllen; 602 return put_user(len, optlen); 603 } 604 case IPV6_MTU: 605 { 606 struct dst_entry *dst; 607 val = 0; 608 lock_sock(sk); 609 dst = sk_dst_get(sk); 610 if (dst) { 611 val = dst_mtu(dst); 612 dst_release(dst); 613 } 614 release_sock(sk); 615 if (!val) 616 return -ENOTCONN; 617 break; 618 } 619 620 case IPV6_V6ONLY: 621 val = np->ipv6only; 622 break; 623 624 case IPV6_PKTINFO: 625 val = np->rxopt.bits.rxinfo; 626 break; 627 628 case IPV6_HOPLIMIT: 629 val = np->rxopt.bits.rxhlim; 630 break; 631 632 case IPV6_RTHDR: 633 val = np->rxopt.bits.srcrt; 634 break; 635 636 case IPV6_HOPOPTS: 637 val = np->rxopt.bits.hopopts; 638 break; 639 640 case IPV6_DSTOPTS: 641 val = np->rxopt.bits.dstopts; 642 break; 643 644 case IPV6_FLOWINFO: 645 val = np->rxopt.bits.rxflow; 646 break; 647 648 case IPV6_UNICAST_HOPS: 649 val = np->hop_limit; 650 break; 651 652 case IPV6_MULTICAST_HOPS: 653 val = np->mcast_hops; 654 break; 655 656 case IPV6_MULTICAST_LOOP: 657 val = np->mc_loop; 658 break; 659 660 case IPV6_MULTICAST_IF: 661 val = np->mcast_oif; 662 break; 663 664 case IPV6_MTU_DISCOVER: 665 val = np->pmtudisc; 666 break; 667 668 case IPV6_RECVERR: 669 val = np->recverr; 670 break; 671 672 case IPV6_FLOWINFO_SEND: 673 val = np->sndflow; 674 break; 675 676 default: 677 #ifdef CONFIG_NETFILTER 678 lock_sock(sk); 679 val = nf_getsockopt(sk, PF_INET6, optname, optval, 680 &len); 681 release_sock(sk); 682 if (val >= 0) 683 val = put_user(len, optlen); 684 return val; 685 #else 686 return -EINVAL; 687 #endif 688 } 689 len = min_t(unsigned int, sizeof(int), len); 690 if(put_user(len, optlen)) 691 return -EFAULT; 692 if(copy_to_user(optval,&val,len)) 693 return -EFAULT; 694 return 0; 695 } 696 697 void __init ipv6_packet_init(void) 698 { 699 dev_add_pack(&ipv6_packet_type); 700 } 701 702 void ipv6_packet_cleanup(void) 703 { 704 dev_remove_pack(&ipv6_packet_type); 705 } 706