1 // SPDX-License-Identifier: GPL-2.0 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 * The IP to API glue. 8 * 9 * Authors: see ip.c 10 * 11 * Fixes: 12 * Many : Split from ip.c , see ip.c for history. 13 * Martin Mares : TOS setting fixed. 14 * Alan Cox : Fixed a couple of oopses in Martin's 15 * TOS tweaks. 16 * Mike McLagan : Routing by source 17 */ 18 19 #include <linux/module.h> 20 #include <linux/types.h> 21 #include <linux/mm.h> 22 #include <linux/skbuff.h> 23 #include <linux/ip.h> 24 #include <linux/icmp.h> 25 #include <linux/inetdevice.h> 26 #include <linux/netdevice.h> 27 #include <linux/slab.h> 28 #include <net/sock.h> 29 #include <net/ip.h> 30 #include <net/icmp.h> 31 #include <net/tcp_states.h> 32 #include <linux/udp.h> 33 #include <linux/igmp.h> 34 #include <linux/netfilter.h> 35 #include <linux/route.h> 36 #include <linux/mroute.h> 37 #include <net/inet_ecn.h> 38 #include <net/route.h> 39 #include <net/xfrm.h> 40 #include <net/compat.h> 41 #include <net/checksum.h> 42 #if IS_ENABLED(CONFIG_IPV6) 43 #include <net/transp_v6.h> 44 #endif 45 #include <net/ip_fib.h> 46 47 #include <linux/errqueue.h> 48 #include <linux/uaccess.h> 49 50 #include <linux/bpfilter.h> 51 52 /* 53 * SOL_IP control messages. 54 */ 55 56 static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb) 57 { 58 struct in_pktinfo info = *PKTINFO_SKB_CB(skb); 59 60 info.ipi_addr.s_addr = ip_hdr(skb)->daddr; 61 62 put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info); 63 } 64 65 static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb) 66 { 67 int ttl = ip_hdr(skb)->ttl; 68 put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl); 69 } 70 71 static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb) 72 { 73 put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos); 74 } 75 76 static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb) 77 { 78 if (IPCB(skb)->opt.optlen == 0) 79 return; 80 81 put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen, 82 ip_hdr(skb) + 1); 83 } 84 85 86 static void ip_cmsg_recv_retopts(struct net *net, struct msghdr *msg, 87 struct sk_buff *skb) 88 { 89 unsigned char optbuf[sizeof(struct ip_options) + 40]; 90 struct ip_options *opt = (struct ip_options *)optbuf; 91 92 if (IPCB(skb)->opt.optlen == 0) 93 return; 94 95 if (ip_options_echo(net, opt, skb)) { 96 msg->msg_flags |= MSG_CTRUNC; 97 return; 98 } 99 ip_options_undo(opt); 100 101 put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data); 102 } 103 104 static void ip_cmsg_recv_fragsize(struct msghdr *msg, struct sk_buff *skb) 105 { 106 int val; 107 108 if (IPCB(skb)->frag_max_size == 0) 109 return; 110 111 val = IPCB(skb)->frag_max_size; 112 put_cmsg(msg, SOL_IP, IP_RECVFRAGSIZE, sizeof(val), &val); 113 } 114 115 static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb, 116 int tlen, int offset) 117 { 118 __wsum csum = skb->csum; 119 120 if (skb->ip_summed != CHECKSUM_COMPLETE) 121 return; 122 123 if (offset != 0) { 124 int tend_off = skb_transport_offset(skb) + tlen; 125 csum = csum_sub(csum, skb_checksum(skb, tend_off, offset, 0)); 126 } 127 128 put_cmsg(msg, SOL_IP, IP_CHECKSUM, sizeof(__wsum), &csum); 129 } 130 131 static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb) 132 { 133 char *secdata; 134 u32 seclen, secid; 135 int err; 136 137 err = security_socket_getpeersec_dgram(NULL, skb, &secid); 138 if (err) 139 return; 140 141 err = security_secid_to_secctx(secid, &secdata, &seclen); 142 if (err) 143 return; 144 145 put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata); 146 security_release_secctx(secdata, seclen); 147 } 148 149 static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb) 150 { 151 __be16 _ports[2], *ports; 152 struct sockaddr_in sin; 153 154 /* All current transport protocols have the port numbers in the 155 * first four bytes of the transport header and this function is 156 * written with this assumption in mind. 157 */ 158 ports = skb_header_pointer(skb, skb_transport_offset(skb), 159 sizeof(_ports), &_ports); 160 if (!ports) 161 return; 162 163 sin.sin_family = AF_INET; 164 sin.sin_addr.s_addr = ip_hdr(skb)->daddr; 165 sin.sin_port = ports[1]; 166 memset(sin.sin_zero, 0, sizeof(sin.sin_zero)); 167 168 put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, sizeof(sin), &sin); 169 } 170 171 void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk, 172 struct sk_buff *skb, int tlen, int offset) 173 { 174 struct inet_sock *inet = inet_sk(sk); 175 unsigned int flags = inet->cmsg_flags; 176 177 /* Ordered by supposed usage frequency */ 178 if (flags & IP_CMSG_PKTINFO) { 179 ip_cmsg_recv_pktinfo(msg, skb); 180 181 flags &= ~IP_CMSG_PKTINFO; 182 if (!flags) 183 return; 184 } 185 186 if (flags & IP_CMSG_TTL) { 187 ip_cmsg_recv_ttl(msg, skb); 188 189 flags &= ~IP_CMSG_TTL; 190 if (!flags) 191 return; 192 } 193 194 if (flags & IP_CMSG_TOS) { 195 ip_cmsg_recv_tos(msg, skb); 196 197 flags &= ~IP_CMSG_TOS; 198 if (!flags) 199 return; 200 } 201 202 if (flags & IP_CMSG_RECVOPTS) { 203 ip_cmsg_recv_opts(msg, skb); 204 205 flags &= ~IP_CMSG_RECVOPTS; 206 if (!flags) 207 return; 208 } 209 210 if (flags & IP_CMSG_RETOPTS) { 211 ip_cmsg_recv_retopts(sock_net(sk), msg, skb); 212 213 flags &= ~IP_CMSG_RETOPTS; 214 if (!flags) 215 return; 216 } 217 218 if (flags & IP_CMSG_PASSSEC) { 219 ip_cmsg_recv_security(msg, skb); 220 221 flags &= ~IP_CMSG_PASSSEC; 222 if (!flags) 223 return; 224 } 225 226 if (flags & IP_CMSG_ORIGDSTADDR) { 227 ip_cmsg_recv_dstaddr(msg, skb); 228 229 flags &= ~IP_CMSG_ORIGDSTADDR; 230 if (!flags) 231 return; 232 } 233 234 if (flags & IP_CMSG_CHECKSUM) 235 ip_cmsg_recv_checksum(msg, skb, tlen, offset); 236 237 if (flags & IP_CMSG_RECVFRAGSIZE) 238 ip_cmsg_recv_fragsize(msg, skb); 239 } 240 EXPORT_SYMBOL(ip_cmsg_recv_offset); 241 242 int ip_cmsg_send(struct sock *sk, struct msghdr *msg, struct ipcm_cookie *ipc, 243 bool allow_ipv6) 244 { 245 int err, val; 246 struct cmsghdr *cmsg; 247 struct net *net = sock_net(sk); 248 249 for_each_cmsghdr(cmsg, msg) { 250 if (!CMSG_OK(msg, cmsg)) 251 return -EINVAL; 252 #if IS_ENABLED(CONFIG_IPV6) 253 if (allow_ipv6 && 254 cmsg->cmsg_level == SOL_IPV6 && 255 cmsg->cmsg_type == IPV6_PKTINFO) { 256 struct in6_pktinfo *src_info; 257 258 if (cmsg->cmsg_len < CMSG_LEN(sizeof(*src_info))) 259 return -EINVAL; 260 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg); 261 if (!ipv6_addr_v4mapped(&src_info->ipi6_addr)) 262 return -EINVAL; 263 if (src_info->ipi6_ifindex) 264 ipc->oif = src_info->ipi6_ifindex; 265 ipc->addr = src_info->ipi6_addr.s6_addr32[3]; 266 continue; 267 } 268 #endif 269 if (cmsg->cmsg_level == SOL_SOCKET) { 270 err = __sock_cmsg_send(sk, msg, cmsg, &ipc->sockc); 271 if (err) 272 return err; 273 continue; 274 } 275 276 if (cmsg->cmsg_level != SOL_IP) 277 continue; 278 switch (cmsg->cmsg_type) { 279 case IP_RETOPTS: 280 err = cmsg->cmsg_len - sizeof(struct cmsghdr); 281 282 /* Our caller is responsible for freeing ipc->opt */ 283 err = ip_options_get(net, &ipc->opt, 284 KERNEL_SOCKPTR(CMSG_DATA(cmsg)), 285 err < 40 ? err : 40); 286 if (err) 287 return err; 288 break; 289 case IP_PKTINFO: 290 { 291 struct in_pktinfo *info; 292 if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo))) 293 return -EINVAL; 294 info = (struct in_pktinfo *)CMSG_DATA(cmsg); 295 if (info->ipi_ifindex) 296 ipc->oif = info->ipi_ifindex; 297 ipc->addr = info->ipi_spec_dst.s_addr; 298 break; 299 } 300 case IP_TTL: 301 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 302 return -EINVAL; 303 val = *(int *)CMSG_DATA(cmsg); 304 if (val < 1 || val > 255) 305 return -EINVAL; 306 ipc->ttl = val; 307 break; 308 case IP_TOS: 309 if (cmsg->cmsg_len == CMSG_LEN(sizeof(int))) 310 val = *(int *)CMSG_DATA(cmsg); 311 else if (cmsg->cmsg_len == CMSG_LEN(sizeof(u8))) 312 val = *(u8 *)CMSG_DATA(cmsg); 313 else 314 return -EINVAL; 315 if (val < 0 || val > 255) 316 return -EINVAL; 317 ipc->tos = val; 318 ipc->priority = rt_tos2priority(ipc->tos); 319 break; 320 321 default: 322 return -EINVAL; 323 } 324 } 325 return 0; 326 } 327 328 static void ip_ra_destroy_rcu(struct rcu_head *head) 329 { 330 struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu); 331 332 sock_put(ra->saved_sk); 333 kfree(ra); 334 } 335 336 int ip_ra_control(struct sock *sk, unsigned char on, 337 void (*destructor)(struct sock *)) 338 { 339 struct ip_ra_chain *ra, *new_ra; 340 struct ip_ra_chain __rcu **rap; 341 struct net *net = sock_net(sk); 342 343 if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW) 344 return -EINVAL; 345 346 new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL; 347 if (on && !new_ra) 348 return -ENOMEM; 349 350 mutex_lock(&net->ipv4.ra_mutex); 351 for (rap = &net->ipv4.ra_chain; 352 (ra = rcu_dereference_protected(*rap, 353 lockdep_is_held(&net->ipv4.ra_mutex))) != NULL; 354 rap = &ra->next) { 355 if (ra->sk == sk) { 356 if (on) { 357 mutex_unlock(&net->ipv4.ra_mutex); 358 kfree(new_ra); 359 return -EADDRINUSE; 360 } 361 /* dont let ip_call_ra_chain() use sk again */ 362 ra->sk = NULL; 363 RCU_INIT_POINTER(*rap, ra->next); 364 mutex_unlock(&net->ipv4.ra_mutex); 365 366 if (ra->destructor) 367 ra->destructor(sk); 368 /* 369 * Delay sock_put(sk) and kfree(ra) after one rcu grace 370 * period. This guarantee ip_call_ra_chain() dont need 371 * to mess with socket refcounts. 372 */ 373 ra->saved_sk = sk; 374 call_rcu(&ra->rcu, ip_ra_destroy_rcu); 375 return 0; 376 } 377 } 378 if (!new_ra) { 379 mutex_unlock(&net->ipv4.ra_mutex); 380 return -ENOBUFS; 381 } 382 new_ra->sk = sk; 383 new_ra->destructor = destructor; 384 385 RCU_INIT_POINTER(new_ra->next, ra); 386 rcu_assign_pointer(*rap, new_ra); 387 sock_hold(sk); 388 mutex_unlock(&net->ipv4.ra_mutex); 389 390 return 0; 391 } 392 393 static void ipv4_icmp_error_rfc4884(const struct sk_buff *skb, 394 struct sock_ee_data_rfc4884 *out) 395 { 396 switch (icmp_hdr(skb)->type) { 397 case ICMP_DEST_UNREACH: 398 case ICMP_TIME_EXCEEDED: 399 case ICMP_PARAMETERPROB: 400 ip_icmp_error_rfc4884(skb, out, sizeof(struct icmphdr), 401 icmp_hdr(skb)->un.reserved[1] * 4); 402 } 403 } 404 405 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, 406 __be16 port, u32 info, u8 *payload) 407 { 408 struct sock_exterr_skb *serr; 409 410 skb = skb_clone(skb, GFP_ATOMIC); 411 if (!skb) 412 return; 413 414 serr = SKB_EXT_ERR(skb); 415 serr->ee.ee_errno = err; 416 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP; 417 serr->ee.ee_type = icmp_hdr(skb)->type; 418 serr->ee.ee_code = icmp_hdr(skb)->code; 419 serr->ee.ee_pad = 0; 420 serr->ee.ee_info = info; 421 serr->ee.ee_data = 0; 422 serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) - 423 skb_network_header(skb); 424 serr->port = port; 425 426 if (skb_pull(skb, payload - skb->data)) { 427 if (inet_sk(sk)->recverr_rfc4884) 428 ipv4_icmp_error_rfc4884(skb, &serr->ee.ee_rfc4884); 429 430 skb_reset_transport_header(skb); 431 if (sock_queue_err_skb(sk, skb) == 0) 432 return; 433 } 434 kfree_skb(skb); 435 } 436 437 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info) 438 { 439 struct inet_sock *inet = inet_sk(sk); 440 struct sock_exterr_skb *serr; 441 struct iphdr *iph; 442 struct sk_buff *skb; 443 444 if (!inet->recverr) 445 return; 446 447 skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC); 448 if (!skb) 449 return; 450 451 skb_put(skb, sizeof(struct iphdr)); 452 skb_reset_network_header(skb); 453 iph = ip_hdr(skb); 454 iph->daddr = daddr; 455 456 serr = SKB_EXT_ERR(skb); 457 serr->ee.ee_errno = err; 458 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; 459 serr->ee.ee_type = 0; 460 serr->ee.ee_code = 0; 461 serr->ee.ee_pad = 0; 462 serr->ee.ee_info = info; 463 serr->ee.ee_data = 0; 464 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb); 465 serr->port = port; 466 467 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 468 skb_reset_transport_header(skb); 469 470 if (sock_queue_err_skb(sk, skb)) 471 kfree_skb(skb); 472 } 473 474 /* For some errors we have valid addr_offset even with zero payload and 475 * zero port. Also, addr_offset should be supported if port is set. 476 */ 477 static inline bool ipv4_datagram_support_addr(struct sock_exterr_skb *serr) 478 { 479 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP || 480 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port; 481 } 482 483 /* IPv4 supports cmsg on all imcp errors and some timestamps 484 * 485 * Timestamp code paths do not initialize the fields expected by cmsg: 486 * the PKTINFO fields in skb->cb[]. Fill those in here. 487 */ 488 static bool ipv4_datagram_support_cmsg(const struct sock *sk, 489 struct sk_buff *skb, 490 int ee_origin) 491 { 492 struct in_pktinfo *info; 493 494 if (ee_origin == SO_EE_ORIGIN_ICMP) 495 return true; 496 497 if (ee_origin == SO_EE_ORIGIN_LOCAL) 498 return false; 499 500 /* Support IP_PKTINFO on tstamp packets if requested, to correlate 501 * timestamp with egress dev. Not possible for packets without iif 502 * or without payload (SOF_TIMESTAMPING_OPT_TSONLY). 503 */ 504 info = PKTINFO_SKB_CB(skb); 505 if (!(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_CMSG) || 506 !info->ipi_ifindex) 507 return false; 508 509 info->ipi_spec_dst.s_addr = ip_hdr(skb)->saddr; 510 return true; 511 } 512 513 /* 514 * Handle MSG_ERRQUEUE 515 */ 516 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) 517 { 518 struct sock_exterr_skb *serr; 519 struct sk_buff *skb; 520 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name); 521 struct { 522 struct sock_extended_err ee; 523 struct sockaddr_in offender; 524 } errhdr; 525 int err; 526 int copied; 527 528 err = -EAGAIN; 529 skb = sock_dequeue_err_skb(sk); 530 if (!skb) 531 goto out; 532 533 copied = skb->len; 534 if (copied > len) { 535 msg->msg_flags |= MSG_TRUNC; 536 copied = len; 537 } 538 err = skb_copy_datagram_msg(skb, 0, msg, copied); 539 if (unlikely(err)) { 540 kfree_skb(skb); 541 return err; 542 } 543 sock_recv_timestamp(msg, sk, skb); 544 545 serr = SKB_EXT_ERR(skb); 546 547 if (sin && ipv4_datagram_support_addr(serr)) { 548 sin->sin_family = AF_INET; 549 sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) + 550 serr->addr_offset); 551 sin->sin_port = serr->port; 552 memset(&sin->sin_zero, 0, sizeof(sin->sin_zero)); 553 *addr_len = sizeof(*sin); 554 } 555 556 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err)); 557 sin = &errhdr.offender; 558 memset(sin, 0, sizeof(*sin)); 559 560 if (ipv4_datagram_support_cmsg(sk, skb, serr->ee.ee_origin)) { 561 sin->sin_family = AF_INET; 562 sin->sin_addr.s_addr = ip_hdr(skb)->saddr; 563 if (inet_sk(sk)->cmsg_flags) 564 ip_cmsg_recv(msg, skb); 565 } 566 567 put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr); 568 569 /* Now we could try to dump offended packet options */ 570 571 msg->msg_flags |= MSG_ERRQUEUE; 572 err = copied; 573 574 consume_skb(skb); 575 out: 576 return err; 577 } 578 579 void __ip_sock_set_tos(struct sock *sk, int val) 580 { 581 if (sk->sk_type == SOCK_STREAM) { 582 val &= ~INET_ECN_MASK; 583 val |= inet_sk(sk)->tos & INET_ECN_MASK; 584 } 585 if (inet_sk(sk)->tos != val) { 586 inet_sk(sk)->tos = val; 587 sk->sk_priority = rt_tos2priority(val); 588 sk_dst_reset(sk); 589 } 590 } 591 592 void ip_sock_set_tos(struct sock *sk, int val) 593 { 594 lock_sock(sk); 595 __ip_sock_set_tos(sk, val); 596 release_sock(sk); 597 } 598 EXPORT_SYMBOL(ip_sock_set_tos); 599 600 void ip_sock_set_freebind(struct sock *sk) 601 { 602 lock_sock(sk); 603 inet_sk(sk)->freebind = true; 604 release_sock(sk); 605 } 606 EXPORT_SYMBOL(ip_sock_set_freebind); 607 608 void ip_sock_set_recverr(struct sock *sk) 609 { 610 lock_sock(sk); 611 inet_sk(sk)->recverr = true; 612 release_sock(sk); 613 } 614 EXPORT_SYMBOL(ip_sock_set_recverr); 615 616 int ip_sock_set_mtu_discover(struct sock *sk, int val) 617 { 618 if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT) 619 return -EINVAL; 620 lock_sock(sk); 621 inet_sk(sk)->pmtudisc = val; 622 release_sock(sk); 623 return 0; 624 } 625 EXPORT_SYMBOL(ip_sock_set_mtu_discover); 626 627 void ip_sock_set_pktinfo(struct sock *sk) 628 { 629 lock_sock(sk); 630 inet_sk(sk)->cmsg_flags |= IP_CMSG_PKTINFO; 631 release_sock(sk); 632 } 633 EXPORT_SYMBOL(ip_sock_set_pktinfo); 634 635 /* 636 * Socket option code for IP. This is the end of the line after any 637 * TCP,UDP etc options on an IP socket. 638 */ 639 static bool setsockopt_needs_rtnl(int optname) 640 { 641 switch (optname) { 642 case IP_ADD_MEMBERSHIP: 643 case IP_ADD_SOURCE_MEMBERSHIP: 644 case IP_BLOCK_SOURCE: 645 case IP_DROP_MEMBERSHIP: 646 case IP_DROP_SOURCE_MEMBERSHIP: 647 case IP_MSFILTER: 648 case IP_UNBLOCK_SOURCE: 649 case MCAST_BLOCK_SOURCE: 650 case MCAST_MSFILTER: 651 case MCAST_JOIN_GROUP: 652 case MCAST_JOIN_SOURCE_GROUP: 653 case MCAST_LEAVE_GROUP: 654 case MCAST_LEAVE_SOURCE_GROUP: 655 case MCAST_UNBLOCK_SOURCE: 656 return true; 657 } 658 return false; 659 } 660 661 static int set_mcast_msfilter(struct sock *sk, int ifindex, 662 int numsrc, int fmode, 663 struct sockaddr_storage *group, 664 struct sockaddr_storage *list) 665 { 666 struct ip_msfilter *msf; 667 struct sockaddr_in *psin; 668 int err, i; 669 670 msf = kmalloc(IP_MSFILTER_SIZE(numsrc), GFP_KERNEL); 671 if (!msf) 672 return -ENOBUFS; 673 674 psin = (struct sockaddr_in *)group; 675 if (psin->sin_family != AF_INET) 676 goto Eaddrnotavail; 677 msf->imsf_multiaddr = psin->sin_addr.s_addr; 678 msf->imsf_interface = 0; 679 msf->imsf_fmode = fmode; 680 msf->imsf_numsrc = numsrc; 681 for (i = 0; i < numsrc; ++i) { 682 psin = (struct sockaddr_in *)&list[i]; 683 684 if (psin->sin_family != AF_INET) 685 goto Eaddrnotavail; 686 msf->imsf_slist_flex[i] = psin->sin_addr.s_addr; 687 } 688 err = ip_mc_msfilter(sk, msf, ifindex); 689 kfree(msf); 690 return err; 691 692 Eaddrnotavail: 693 kfree(msf); 694 return -EADDRNOTAVAIL; 695 } 696 697 static int copy_group_source_from_sockptr(struct group_source_req *greqs, 698 sockptr_t optval, int optlen) 699 { 700 if (in_compat_syscall()) { 701 struct compat_group_source_req gr32; 702 703 if (optlen != sizeof(gr32)) 704 return -EINVAL; 705 if (copy_from_sockptr(&gr32, optval, sizeof(gr32))) 706 return -EFAULT; 707 greqs->gsr_interface = gr32.gsr_interface; 708 greqs->gsr_group = gr32.gsr_group; 709 greqs->gsr_source = gr32.gsr_source; 710 } else { 711 if (optlen != sizeof(*greqs)) 712 return -EINVAL; 713 if (copy_from_sockptr(greqs, optval, sizeof(*greqs))) 714 return -EFAULT; 715 } 716 717 return 0; 718 } 719 720 static int do_mcast_group_source(struct sock *sk, int optname, 721 sockptr_t optval, int optlen) 722 { 723 struct group_source_req greqs; 724 struct ip_mreq_source mreqs; 725 struct sockaddr_in *psin; 726 int omode, add, err; 727 728 err = copy_group_source_from_sockptr(&greqs, optval, optlen); 729 if (err) 730 return err; 731 732 if (greqs.gsr_group.ss_family != AF_INET || 733 greqs.gsr_source.ss_family != AF_INET) 734 return -EADDRNOTAVAIL; 735 736 psin = (struct sockaddr_in *)&greqs.gsr_group; 737 mreqs.imr_multiaddr = psin->sin_addr.s_addr; 738 psin = (struct sockaddr_in *)&greqs.gsr_source; 739 mreqs.imr_sourceaddr = psin->sin_addr.s_addr; 740 mreqs.imr_interface = 0; /* use index for mc_source */ 741 742 if (optname == MCAST_BLOCK_SOURCE) { 743 omode = MCAST_EXCLUDE; 744 add = 1; 745 } else if (optname == MCAST_UNBLOCK_SOURCE) { 746 omode = MCAST_EXCLUDE; 747 add = 0; 748 } else if (optname == MCAST_JOIN_SOURCE_GROUP) { 749 struct ip_mreqn mreq; 750 751 psin = (struct sockaddr_in *)&greqs.gsr_group; 752 mreq.imr_multiaddr = psin->sin_addr; 753 mreq.imr_address.s_addr = 0; 754 mreq.imr_ifindex = greqs.gsr_interface; 755 err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE); 756 if (err && err != -EADDRINUSE) 757 return err; 758 greqs.gsr_interface = mreq.imr_ifindex; 759 omode = MCAST_INCLUDE; 760 add = 1; 761 } else /* MCAST_LEAVE_SOURCE_GROUP */ { 762 omode = MCAST_INCLUDE; 763 add = 0; 764 } 765 return ip_mc_source(add, omode, sk, &mreqs, greqs.gsr_interface); 766 } 767 768 static int ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval, int optlen) 769 { 770 struct group_filter *gsf = NULL; 771 int err; 772 773 if (optlen < GROUP_FILTER_SIZE(0)) 774 return -EINVAL; 775 if (optlen > sysctl_optmem_max) 776 return -ENOBUFS; 777 778 gsf = memdup_sockptr(optval, optlen); 779 if (IS_ERR(gsf)) 780 return PTR_ERR(gsf); 781 782 /* numsrc >= (4G-140)/128 overflow in 32 bits */ 783 err = -ENOBUFS; 784 if (gsf->gf_numsrc >= 0x1ffffff || 785 gsf->gf_numsrc > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf)) 786 goto out_free_gsf; 787 788 err = -EINVAL; 789 if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) 790 goto out_free_gsf; 791 792 err = set_mcast_msfilter(sk, gsf->gf_interface, gsf->gf_numsrc, 793 gsf->gf_fmode, &gsf->gf_group, 794 gsf->gf_slist_flex); 795 out_free_gsf: 796 kfree(gsf); 797 return err; 798 } 799 800 static int compat_ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval, 801 int optlen) 802 { 803 const int size0 = offsetof(struct compat_group_filter, gf_slist_flex); 804 struct compat_group_filter *gf32; 805 unsigned int n; 806 void *p; 807 int err; 808 809 if (optlen < size0) 810 return -EINVAL; 811 if (optlen > sysctl_optmem_max - 4) 812 return -ENOBUFS; 813 814 p = kmalloc(optlen + 4, GFP_KERNEL); 815 if (!p) 816 return -ENOMEM; 817 gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */ 818 819 err = -EFAULT; 820 if (copy_from_sockptr(gf32, optval, optlen)) 821 goto out_free_gsf; 822 823 /* numsrc >= (4G-140)/128 overflow in 32 bits */ 824 n = gf32->gf_numsrc; 825 err = -ENOBUFS; 826 if (n >= 0x1ffffff) 827 goto out_free_gsf; 828 829 err = -EINVAL; 830 if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen) 831 goto out_free_gsf; 832 833 /* numsrc >= (4G-140)/128 overflow in 32 bits */ 834 err = -ENOBUFS; 835 if (n > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf)) 836 goto out_free_gsf; 837 err = set_mcast_msfilter(sk, gf32->gf_interface, n, gf32->gf_fmode, 838 &gf32->gf_group, gf32->gf_slist_flex); 839 out_free_gsf: 840 kfree(p); 841 return err; 842 } 843 844 static int ip_mcast_join_leave(struct sock *sk, int optname, 845 sockptr_t optval, int optlen) 846 { 847 struct ip_mreqn mreq = { }; 848 struct sockaddr_in *psin; 849 struct group_req greq; 850 851 if (optlen < sizeof(struct group_req)) 852 return -EINVAL; 853 if (copy_from_sockptr(&greq, optval, sizeof(greq))) 854 return -EFAULT; 855 856 psin = (struct sockaddr_in *)&greq.gr_group; 857 if (psin->sin_family != AF_INET) 858 return -EINVAL; 859 mreq.imr_multiaddr = psin->sin_addr; 860 mreq.imr_ifindex = greq.gr_interface; 861 if (optname == MCAST_JOIN_GROUP) 862 return ip_mc_join_group(sk, &mreq); 863 return ip_mc_leave_group(sk, &mreq); 864 } 865 866 static int compat_ip_mcast_join_leave(struct sock *sk, int optname, 867 sockptr_t optval, int optlen) 868 { 869 struct compat_group_req greq; 870 struct ip_mreqn mreq = { }; 871 struct sockaddr_in *psin; 872 873 if (optlen < sizeof(struct compat_group_req)) 874 return -EINVAL; 875 if (copy_from_sockptr(&greq, optval, sizeof(greq))) 876 return -EFAULT; 877 878 psin = (struct sockaddr_in *)&greq.gr_group; 879 if (psin->sin_family != AF_INET) 880 return -EINVAL; 881 mreq.imr_multiaddr = psin->sin_addr; 882 mreq.imr_ifindex = greq.gr_interface; 883 884 if (optname == MCAST_JOIN_GROUP) 885 return ip_mc_join_group(sk, &mreq); 886 return ip_mc_leave_group(sk, &mreq); 887 } 888 889 DEFINE_STATIC_KEY_FALSE(ip4_min_ttl); 890 891 static int do_ip_setsockopt(struct sock *sk, int level, int optname, 892 sockptr_t optval, unsigned int optlen) 893 { 894 struct inet_sock *inet = inet_sk(sk); 895 struct net *net = sock_net(sk); 896 int val = 0, err; 897 bool needs_rtnl = setsockopt_needs_rtnl(optname); 898 899 switch (optname) { 900 case IP_PKTINFO: 901 case IP_RECVTTL: 902 case IP_RECVOPTS: 903 case IP_RECVTOS: 904 case IP_RETOPTS: 905 case IP_TOS: 906 case IP_TTL: 907 case IP_HDRINCL: 908 case IP_MTU_DISCOVER: 909 case IP_RECVERR: 910 case IP_ROUTER_ALERT: 911 case IP_FREEBIND: 912 case IP_PASSSEC: 913 case IP_TRANSPARENT: 914 case IP_MINTTL: 915 case IP_NODEFRAG: 916 case IP_BIND_ADDRESS_NO_PORT: 917 case IP_UNICAST_IF: 918 case IP_MULTICAST_TTL: 919 case IP_MULTICAST_ALL: 920 case IP_MULTICAST_LOOP: 921 case IP_RECVORIGDSTADDR: 922 case IP_CHECKSUM: 923 case IP_RECVFRAGSIZE: 924 case IP_RECVERR_RFC4884: 925 if (optlen >= sizeof(int)) { 926 if (copy_from_sockptr(&val, optval, sizeof(val))) 927 return -EFAULT; 928 } else if (optlen >= sizeof(char)) { 929 unsigned char ucval; 930 931 if (copy_from_sockptr(&ucval, optval, sizeof(ucval))) 932 return -EFAULT; 933 val = (int) ucval; 934 } 935 } 936 937 /* If optlen==0, it is equivalent to val == 0 */ 938 939 if (optname == IP_ROUTER_ALERT) 940 return ip_ra_control(sk, val ? 1 : 0, NULL); 941 if (ip_mroute_opt(optname)) 942 return ip_mroute_setsockopt(sk, optname, optval, optlen); 943 944 err = 0; 945 if (needs_rtnl) 946 rtnl_lock(); 947 lock_sock(sk); 948 949 switch (optname) { 950 case IP_OPTIONS: 951 { 952 struct ip_options_rcu *old, *opt = NULL; 953 954 if (optlen > 40) 955 goto e_inval; 956 err = ip_options_get(sock_net(sk), &opt, optval, optlen); 957 if (err) 958 break; 959 old = rcu_dereference_protected(inet->inet_opt, 960 lockdep_sock_is_held(sk)); 961 if (inet->is_icsk) { 962 struct inet_connection_sock *icsk = inet_csk(sk); 963 #if IS_ENABLED(CONFIG_IPV6) 964 if (sk->sk_family == PF_INET || 965 (!((1 << sk->sk_state) & 966 (TCPF_LISTEN | TCPF_CLOSE)) && 967 inet->inet_daddr != LOOPBACK4_IPV6)) { 968 #endif 969 if (old) 970 icsk->icsk_ext_hdr_len -= old->opt.optlen; 971 if (opt) 972 icsk->icsk_ext_hdr_len += opt->opt.optlen; 973 icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie); 974 #if IS_ENABLED(CONFIG_IPV6) 975 } 976 #endif 977 } 978 rcu_assign_pointer(inet->inet_opt, opt); 979 if (old) 980 kfree_rcu(old, rcu); 981 break; 982 } 983 case IP_PKTINFO: 984 if (val) 985 inet->cmsg_flags |= IP_CMSG_PKTINFO; 986 else 987 inet->cmsg_flags &= ~IP_CMSG_PKTINFO; 988 break; 989 case IP_RECVTTL: 990 if (val) 991 inet->cmsg_flags |= IP_CMSG_TTL; 992 else 993 inet->cmsg_flags &= ~IP_CMSG_TTL; 994 break; 995 case IP_RECVTOS: 996 if (val) 997 inet->cmsg_flags |= IP_CMSG_TOS; 998 else 999 inet->cmsg_flags &= ~IP_CMSG_TOS; 1000 break; 1001 case IP_RECVOPTS: 1002 if (val) 1003 inet->cmsg_flags |= IP_CMSG_RECVOPTS; 1004 else 1005 inet->cmsg_flags &= ~IP_CMSG_RECVOPTS; 1006 break; 1007 case IP_RETOPTS: 1008 if (val) 1009 inet->cmsg_flags |= IP_CMSG_RETOPTS; 1010 else 1011 inet->cmsg_flags &= ~IP_CMSG_RETOPTS; 1012 break; 1013 case IP_PASSSEC: 1014 if (val) 1015 inet->cmsg_flags |= IP_CMSG_PASSSEC; 1016 else 1017 inet->cmsg_flags &= ~IP_CMSG_PASSSEC; 1018 break; 1019 case IP_RECVORIGDSTADDR: 1020 if (val) 1021 inet->cmsg_flags |= IP_CMSG_ORIGDSTADDR; 1022 else 1023 inet->cmsg_flags &= ~IP_CMSG_ORIGDSTADDR; 1024 break; 1025 case IP_CHECKSUM: 1026 if (val) { 1027 if (!(inet->cmsg_flags & IP_CMSG_CHECKSUM)) { 1028 inet_inc_convert_csum(sk); 1029 inet->cmsg_flags |= IP_CMSG_CHECKSUM; 1030 } 1031 } else { 1032 if (inet->cmsg_flags & IP_CMSG_CHECKSUM) { 1033 inet_dec_convert_csum(sk); 1034 inet->cmsg_flags &= ~IP_CMSG_CHECKSUM; 1035 } 1036 } 1037 break; 1038 case IP_RECVFRAGSIZE: 1039 if (sk->sk_type != SOCK_RAW && sk->sk_type != SOCK_DGRAM) 1040 goto e_inval; 1041 if (val) 1042 inet->cmsg_flags |= IP_CMSG_RECVFRAGSIZE; 1043 else 1044 inet->cmsg_flags &= ~IP_CMSG_RECVFRAGSIZE; 1045 break; 1046 case IP_TOS: /* This sets both TOS and Precedence */ 1047 __ip_sock_set_tos(sk, val); 1048 break; 1049 case IP_TTL: 1050 if (optlen < 1) 1051 goto e_inval; 1052 if (val != -1 && (val < 1 || val > 255)) 1053 goto e_inval; 1054 inet->uc_ttl = val; 1055 break; 1056 case IP_HDRINCL: 1057 if (sk->sk_type != SOCK_RAW) { 1058 err = -ENOPROTOOPT; 1059 break; 1060 } 1061 inet->hdrincl = val ? 1 : 0; 1062 break; 1063 case IP_NODEFRAG: 1064 if (sk->sk_type != SOCK_RAW) { 1065 err = -ENOPROTOOPT; 1066 break; 1067 } 1068 inet->nodefrag = val ? 1 : 0; 1069 break; 1070 case IP_BIND_ADDRESS_NO_PORT: 1071 inet->bind_address_no_port = val ? 1 : 0; 1072 break; 1073 case IP_MTU_DISCOVER: 1074 if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT) 1075 goto e_inval; 1076 inet->pmtudisc = val; 1077 break; 1078 case IP_RECVERR: 1079 inet->recverr = !!val; 1080 if (!val) 1081 skb_queue_purge(&sk->sk_error_queue); 1082 break; 1083 case IP_RECVERR_RFC4884: 1084 if (val < 0 || val > 1) 1085 goto e_inval; 1086 inet->recverr_rfc4884 = !!val; 1087 break; 1088 case IP_MULTICAST_TTL: 1089 if (sk->sk_type == SOCK_STREAM) 1090 goto e_inval; 1091 if (optlen < 1) 1092 goto e_inval; 1093 if (val == -1) 1094 val = 1; 1095 if (val < 0 || val > 255) 1096 goto e_inval; 1097 inet->mc_ttl = val; 1098 break; 1099 case IP_MULTICAST_LOOP: 1100 if (optlen < 1) 1101 goto e_inval; 1102 inet->mc_loop = !!val; 1103 break; 1104 case IP_UNICAST_IF: 1105 { 1106 struct net_device *dev = NULL; 1107 int ifindex; 1108 int midx; 1109 1110 if (optlen != sizeof(int)) 1111 goto e_inval; 1112 1113 ifindex = (__force int)ntohl((__force __be32)val); 1114 if (ifindex == 0) { 1115 inet->uc_index = 0; 1116 err = 0; 1117 break; 1118 } 1119 1120 dev = dev_get_by_index(sock_net(sk), ifindex); 1121 err = -EADDRNOTAVAIL; 1122 if (!dev) 1123 break; 1124 1125 midx = l3mdev_master_ifindex(dev); 1126 dev_put(dev); 1127 1128 err = -EINVAL; 1129 if (sk->sk_bound_dev_if && midx != sk->sk_bound_dev_if) 1130 break; 1131 1132 inet->uc_index = ifindex; 1133 err = 0; 1134 break; 1135 } 1136 case IP_MULTICAST_IF: 1137 { 1138 struct ip_mreqn mreq; 1139 struct net_device *dev = NULL; 1140 int midx; 1141 1142 if (sk->sk_type == SOCK_STREAM) 1143 goto e_inval; 1144 /* 1145 * Check the arguments are allowable 1146 */ 1147 1148 if (optlen < sizeof(struct in_addr)) 1149 goto e_inval; 1150 1151 err = -EFAULT; 1152 if (optlen >= sizeof(struct ip_mreqn)) { 1153 if (copy_from_sockptr(&mreq, optval, sizeof(mreq))) 1154 break; 1155 } else { 1156 memset(&mreq, 0, sizeof(mreq)); 1157 if (optlen >= sizeof(struct ip_mreq)) { 1158 if (copy_from_sockptr(&mreq, optval, 1159 sizeof(struct ip_mreq))) 1160 break; 1161 } else if (optlen >= sizeof(struct in_addr)) { 1162 if (copy_from_sockptr(&mreq.imr_address, optval, 1163 sizeof(struct in_addr))) 1164 break; 1165 } 1166 } 1167 1168 if (!mreq.imr_ifindex) { 1169 if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) { 1170 inet->mc_index = 0; 1171 inet->mc_addr = 0; 1172 err = 0; 1173 break; 1174 } 1175 dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr); 1176 if (dev) 1177 mreq.imr_ifindex = dev->ifindex; 1178 } else 1179 dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex); 1180 1181 1182 err = -EADDRNOTAVAIL; 1183 if (!dev) 1184 break; 1185 1186 midx = l3mdev_master_ifindex(dev); 1187 1188 dev_put(dev); 1189 1190 err = -EINVAL; 1191 if (sk->sk_bound_dev_if && 1192 mreq.imr_ifindex != sk->sk_bound_dev_if && 1193 midx != sk->sk_bound_dev_if) 1194 break; 1195 1196 inet->mc_index = mreq.imr_ifindex; 1197 inet->mc_addr = mreq.imr_address.s_addr; 1198 err = 0; 1199 break; 1200 } 1201 1202 case IP_ADD_MEMBERSHIP: 1203 case IP_DROP_MEMBERSHIP: 1204 { 1205 struct ip_mreqn mreq; 1206 1207 err = -EPROTO; 1208 if (inet_sk(sk)->is_icsk) 1209 break; 1210 1211 if (optlen < sizeof(struct ip_mreq)) 1212 goto e_inval; 1213 err = -EFAULT; 1214 if (optlen >= sizeof(struct ip_mreqn)) { 1215 if (copy_from_sockptr(&mreq, optval, sizeof(mreq))) 1216 break; 1217 } else { 1218 memset(&mreq, 0, sizeof(mreq)); 1219 if (copy_from_sockptr(&mreq, optval, 1220 sizeof(struct ip_mreq))) 1221 break; 1222 } 1223 1224 if (optname == IP_ADD_MEMBERSHIP) 1225 err = ip_mc_join_group(sk, &mreq); 1226 else 1227 err = ip_mc_leave_group(sk, &mreq); 1228 break; 1229 } 1230 case IP_MSFILTER: 1231 { 1232 struct ip_msfilter *msf; 1233 1234 if (optlen < IP_MSFILTER_SIZE(0)) 1235 goto e_inval; 1236 if (optlen > sysctl_optmem_max) { 1237 err = -ENOBUFS; 1238 break; 1239 } 1240 msf = memdup_sockptr(optval, optlen); 1241 if (IS_ERR(msf)) { 1242 err = PTR_ERR(msf); 1243 break; 1244 } 1245 /* numsrc >= (1G-4) overflow in 32 bits */ 1246 if (msf->imsf_numsrc >= 0x3ffffffcU || 1247 msf->imsf_numsrc > READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) { 1248 kfree(msf); 1249 err = -ENOBUFS; 1250 break; 1251 } 1252 if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) { 1253 kfree(msf); 1254 err = -EINVAL; 1255 break; 1256 } 1257 err = ip_mc_msfilter(sk, msf, 0); 1258 kfree(msf); 1259 break; 1260 } 1261 case IP_BLOCK_SOURCE: 1262 case IP_UNBLOCK_SOURCE: 1263 case IP_ADD_SOURCE_MEMBERSHIP: 1264 case IP_DROP_SOURCE_MEMBERSHIP: 1265 { 1266 struct ip_mreq_source mreqs; 1267 int omode, add; 1268 1269 if (optlen != sizeof(struct ip_mreq_source)) 1270 goto e_inval; 1271 if (copy_from_sockptr(&mreqs, optval, sizeof(mreqs))) { 1272 err = -EFAULT; 1273 break; 1274 } 1275 if (optname == IP_BLOCK_SOURCE) { 1276 omode = MCAST_EXCLUDE; 1277 add = 1; 1278 } else if (optname == IP_UNBLOCK_SOURCE) { 1279 omode = MCAST_EXCLUDE; 1280 add = 0; 1281 } else if (optname == IP_ADD_SOURCE_MEMBERSHIP) { 1282 struct ip_mreqn mreq; 1283 1284 mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr; 1285 mreq.imr_address.s_addr = mreqs.imr_interface; 1286 mreq.imr_ifindex = 0; 1287 err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE); 1288 if (err && err != -EADDRINUSE) 1289 break; 1290 omode = MCAST_INCLUDE; 1291 add = 1; 1292 } else /* IP_DROP_SOURCE_MEMBERSHIP */ { 1293 omode = MCAST_INCLUDE; 1294 add = 0; 1295 } 1296 err = ip_mc_source(add, omode, sk, &mreqs, 0); 1297 break; 1298 } 1299 case MCAST_JOIN_GROUP: 1300 case MCAST_LEAVE_GROUP: 1301 if (in_compat_syscall()) 1302 err = compat_ip_mcast_join_leave(sk, optname, optval, 1303 optlen); 1304 else 1305 err = ip_mcast_join_leave(sk, optname, optval, optlen); 1306 break; 1307 case MCAST_JOIN_SOURCE_GROUP: 1308 case MCAST_LEAVE_SOURCE_GROUP: 1309 case MCAST_BLOCK_SOURCE: 1310 case MCAST_UNBLOCK_SOURCE: 1311 err = do_mcast_group_source(sk, optname, optval, optlen); 1312 break; 1313 case MCAST_MSFILTER: 1314 if (in_compat_syscall()) 1315 err = compat_ip_set_mcast_msfilter(sk, optval, optlen); 1316 else 1317 err = ip_set_mcast_msfilter(sk, optval, optlen); 1318 break; 1319 case IP_MULTICAST_ALL: 1320 if (optlen < 1) 1321 goto e_inval; 1322 if (val != 0 && val != 1) 1323 goto e_inval; 1324 inet->mc_all = val; 1325 break; 1326 1327 case IP_FREEBIND: 1328 if (optlen < 1) 1329 goto e_inval; 1330 inet->freebind = !!val; 1331 break; 1332 1333 case IP_IPSEC_POLICY: 1334 case IP_XFRM_POLICY: 1335 err = -EPERM; 1336 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 1337 break; 1338 err = xfrm_user_policy(sk, optname, optval, optlen); 1339 break; 1340 1341 case IP_TRANSPARENT: 1342 if (!!val && !ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) && 1343 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1344 err = -EPERM; 1345 break; 1346 } 1347 if (optlen < 1) 1348 goto e_inval; 1349 inet->transparent = !!val; 1350 break; 1351 1352 case IP_MINTTL: 1353 if (optlen < 1) 1354 goto e_inval; 1355 if (val < 0 || val > 255) 1356 goto e_inval; 1357 1358 if (val) 1359 static_branch_enable(&ip4_min_ttl); 1360 1361 /* tcp_v4_err() and tcp_v4_rcv() might read min_ttl 1362 * while we are changint it. 1363 */ 1364 WRITE_ONCE(inet->min_ttl, val); 1365 break; 1366 1367 default: 1368 err = -ENOPROTOOPT; 1369 break; 1370 } 1371 release_sock(sk); 1372 if (needs_rtnl) 1373 rtnl_unlock(); 1374 return err; 1375 1376 e_inval: 1377 release_sock(sk); 1378 if (needs_rtnl) 1379 rtnl_unlock(); 1380 return -EINVAL; 1381 } 1382 1383 /** 1384 * ipv4_pktinfo_prepare - transfer some info from rtable to skb 1385 * @sk: socket 1386 * @skb: buffer 1387 * 1388 * To support IP_CMSG_PKTINFO option, we store rt_iif and specific 1389 * destination in skb->cb[] before dst drop. 1390 * This way, receiver doesn't make cache line misses to read rtable. 1391 */ 1392 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb) 1393 { 1394 struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb); 1395 bool prepare = (inet_sk(sk)->cmsg_flags & IP_CMSG_PKTINFO) || 1396 ipv6_sk_rxinfo(sk); 1397 1398 if (prepare && skb_rtable(skb)) { 1399 /* skb->cb is overloaded: prior to this point it is IP{6}CB 1400 * which has interface index (iif) as the first member of the 1401 * underlying inet{6}_skb_parm struct. This code then overlays 1402 * PKTINFO_SKB_CB and in_pktinfo also has iif as the first 1403 * element so the iif is picked up from the prior IPCB. If iif 1404 * is the loopback interface, then return the sending interface 1405 * (e.g., process binds socket to eth0 for Tx which is 1406 * redirected to loopback in the rtable/dst). 1407 */ 1408 struct rtable *rt = skb_rtable(skb); 1409 bool l3slave = ipv4_l3mdev_skb(IPCB(skb)->flags); 1410 1411 if (pktinfo->ipi_ifindex == LOOPBACK_IFINDEX) 1412 pktinfo->ipi_ifindex = inet_iif(skb); 1413 else if (l3slave && rt && rt->rt_iif) 1414 pktinfo->ipi_ifindex = rt->rt_iif; 1415 1416 pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb); 1417 } else { 1418 pktinfo->ipi_ifindex = 0; 1419 pktinfo->ipi_spec_dst.s_addr = 0; 1420 } 1421 skb_dst_drop(skb); 1422 } 1423 1424 int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, 1425 unsigned int optlen) 1426 { 1427 int err; 1428 1429 if (level != SOL_IP) 1430 return -ENOPROTOOPT; 1431 1432 err = do_ip_setsockopt(sk, level, optname, optval, optlen); 1433 #if IS_ENABLED(CONFIG_BPFILTER_UMH) 1434 if (optname >= BPFILTER_IPT_SO_SET_REPLACE && 1435 optname < BPFILTER_IPT_SET_MAX) 1436 err = bpfilter_ip_set_sockopt(sk, optname, optval, optlen); 1437 #endif 1438 #ifdef CONFIG_NETFILTER 1439 /* we need to exclude all possible ENOPROTOOPTs except default case */ 1440 if (err == -ENOPROTOOPT && optname != IP_HDRINCL && 1441 optname != IP_IPSEC_POLICY && 1442 optname != IP_XFRM_POLICY && 1443 !ip_mroute_opt(optname)) 1444 err = nf_setsockopt(sk, PF_INET, optname, optval, optlen); 1445 #endif 1446 return err; 1447 } 1448 EXPORT_SYMBOL(ip_setsockopt); 1449 1450 /* 1451 * Get the options. Note for future reference. The GET of IP options gets 1452 * the _received_ ones. The set sets the _sent_ ones. 1453 */ 1454 1455 static bool getsockopt_needs_rtnl(int optname) 1456 { 1457 switch (optname) { 1458 case IP_MSFILTER: 1459 case MCAST_MSFILTER: 1460 return true; 1461 } 1462 return false; 1463 } 1464 1465 static int ip_get_mcast_msfilter(struct sock *sk, void __user *optval, 1466 int __user *optlen, int len) 1467 { 1468 const int size0 = offsetof(struct group_filter, gf_slist_flex); 1469 struct group_filter __user *p = optval; 1470 struct group_filter gsf; 1471 int num; 1472 int err; 1473 1474 if (len < size0) 1475 return -EINVAL; 1476 if (copy_from_user(&gsf, p, size0)) 1477 return -EFAULT; 1478 1479 num = gsf.gf_numsrc; 1480 err = ip_mc_gsfget(sk, &gsf, p->gf_slist_flex); 1481 if (err) 1482 return err; 1483 if (gsf.gf_numsrc < num) 1484 num = gsf.gf_numsrc; 1485 if (put_user(GROUP_FILTER_SIZE(num), optlen) || 1486 copy_to_user(p, &gsf, size0)) 1487 return -EFAULT; 1488 return 0; 1489 } 1490 1491 static int compat_ip_get_mcast_msfilter(struct sock *sk, void __user *optval, 1492 int __user *optlen, int len) 1493 { 1494 const int size0 = offsetof(struct compat_group_filter, gf_slist_flex); 1495 struct compat_group_filter __user *p = optval; 1496 struct compat_group_filter gf32; 1497 struct group_filter gf; 1498 int num; 1499 int err; 1500 1501 if (len < size0) 1502 return -EINVAL; 1503 if (copy_from_user(&gf32, p, size0)) 1504 return -EFAULT; 1505 1506 gf.gf_interface = gf32.gf_interface; 1507 gf.gf_fmode = gf32.gf_fmode; 1508 num = gf.gf_numsrc = gf32.gf_numsrc; 1509 gf.gf_group = gf32.gf_group; 1510 1511 err = ip_mc_gsfget(sk, &gf, p->gf_slist_flex); 1512 if (err) 1513 return err; 1514 if (gf.gf_numsrc < num) 1515 num = gf.gf_numsrc; 1516 len = GROUP_FILTER_SIZE(num) - (sizeof(gf) - sizeof(gf32)); 1517 if (put_user(len, optlen) || 1518 put_user(gf.gf_fmode, &p->gf_fmode) || 1519 put_user(gf.gf_numsrc, &p->gf_numsrc)) 1520 return -EFAULT; 1521 return 0; 1522 } 1523 1524 static int do_ip_getsockopt(struct sock *sk, int level, int optname, 1525 char __user *optval, int __user *optlen) 1526 { 1527 struct inet_sock *inet = inet_sk(sk); 1528 bool needs_rtnl = getsockopt_needs_rtnl(optname); 1529 int val, err = 0; 1530 int len; 1531 1532 if (level != SOL_IP) 1533 return -EOPNOTSUPP; 1534 1535 if (ip_mroute_opt(optname)) 1536 return ip_mroute_getsockopt(sk, optname, optval, optlen); 1537 1538 if (get_user(len, optlen)) 1539 return -EFAULT; 1540 if (len < 0) 1541 return -EINVAL; 1542 1543 if (needs_rtnl) 1544 rtnl_lock(); 1545 lock_sock(sk); 1546 1547 switch (optname) { 1548 case IP_OPTIONS: 1549 { 1550 unsigned char optbuf[sizeof(struct ip_options)+40]; 1551 struct ip_options *opt = (struct ip_options *)optbuf; 1552 struct ip_options_rcu *inet_opt; 1553 1554 inet_opt = rcu_dereference_protected(inet->inet_opt, 1555 lockdep_sock_is_held(sk)); 1556 opt->optlen = 0; 1557 if (inet_opt) 1558 memcpy(optbuf, &inet_opt->opt, 1559 sizeof(struct ip_options) + 1560 inet_opt->opt.optlen); 1561 release_sock(sk); 1562 1563 if (opt->optlen == 0) 1564 return put_user(0, optlen); 1565 1566 ip_options_undo(opt); 1567 1568 len = min_t(unsigned int, len, opt->optlen); 1569 if (put_user(len, optlen)) 1570 return -EFAULT; 1571 if (copy_to_user(optval, opt->__data, len)) 1572 return -EFAULT; 1573 return 0; 1574 } 1575 case IP_PKTINFO: 1576 val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0; 1577 break; 1578 case IP_RECVTTL: 1579 val = (inet->cmsg_flags & IP_CMSG_TTL) != 0; 1580 break; 1581 case IP_RECVTOS: 1582 val = (inet->cmsg_flags & IP_CMSG_TOS) != 0; 1583 break; 1584 case IP_RECVOPTS: 1585 val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0; 1586 break; 1587 case IP_RETOPTS: 1588 val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0; 1589 break; 1590 case IP_PASSSEC: 1591 val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0; 1592 break; 1593 case IP_RECVORIGDSTADDR: 1594 val = (inet->cmsg_flags & IP_CMSG_ORIGDSTADDR) != 0; 1595 break; 1596 case IP_CHECKSUM: 1597 val = (inet->cmsg_flags & IP_CMSG_CHECKSUM) != 0; 1598 break; 1599 case IP_RECVFRAGSIZE: 1600 val = (inet->cmsg_flags & IP_CMSG_RECVFRAGSIZE) != 0; 1601 break; 1602 case IP_TOS: 1603 val = inet->tos; 1604 break; 1605 case IP_TTL: 1606 { 1607 struct net *net = sock_net(sk); 1608 val = (inet->uc_ttl == -1 ? 1609 READ_ONCE(net->ipv4.sysctl_ip_default_ttl) : 1610 inet->uc_ttl); 1611 break; 1612 } 1613 case IP_HDRINCL: 1614 val = inet->hdrincl; 1615 break; 1616 case IP_NODEFRAG: 1617 val = inet->nodefrag; 1618 break; 1619 case IP_BIND_ADDRESS_NO_PORT: 1620 val = inet->bind_address_no_port; 1621 break; 1622 case IP_MTU_DISCOVER: 1623 val = inet->pmtudisc; 1624 break; 1625 case IP_MTU: 1626 { 1627 struct dst_entry *dst; 1628 val = 0; 1629 dst = sk_dst_get(sk); 1630 if (dst) { 1631 val = dst_mtu(dst); 1632 dst_release(dst); 1633 } 1634 if (!val) { 1635 release_sock(sk); 1636 return -ENOTCONN; 1637 } 1638 break; 1639 } 1640 case IP_RECVERR: 1641 val = inet->recverr; 1642 break; 1643 case IP_RECVERR_RFC4884: 1644 val = inet->recverr_rfc4884; 1645 break; 1646 case IP_MULTICAST_TTL: 1647 val = inet->mc_ttl; 1648 break; 1649 case IP_MULTICAST_LOOP: 1650 val = inet->mc_loop; 1651 break; 1652 case IP_UNICAST_IF: 1653 val = (__force int)htonl((__u32) inet->uc_index); 1654 break; 1655 case IP_MULTICAST_IF: 1656 { 1657 struct in_addr addr; 1658 len = min_t(unsigned int, len, sizeof(struct in_addr)); 1659 addr.s_addr = inet->mc_addr; 1660 release_sock(sk); 1661 1662 if (put_user(len, optlen)) 1663 return -EFAULT; 1664 if (copy_to_user(optval, &addr, len)) 1665 return -EFAULT; 1666 return 0; 1667 } 1668 case IP_MSFILTER: 1669 { 1670 struct ip_msfilter msf; 1671 1672 if (len < IP_MSFILTER_SIZE(0)) { 1673 err = -EINVAL; 1674 goto out; 1675 } 1676 if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) { 1677 err = -EFAULT; 1678 goto out; 1679 } 1680 err = ip_mc_msfget(sk, &msf, 1681 (struct ip_msfilter __user *)optval, optlen); 1682 goto out; 1683 } 1684 case MCAST_MSFILTER: 1685 if (in_compat_syscall()) 1686 err = compat_ip_get_mcast_msfilter(sk, optval, optlen, 1687 len); 1688 else 1689 err = ip_get_mcast_msfilter(sk, optval, optlen, len); 1690 goto out; 1691 case IP_MULTICAST_ALL: 1692 val = inet->mc_all; 1693 break; 1694 case IP_PKTOPTIONS: 1695 { 1696 struct msghdr msg; 1697 1698 release_sock(sk); 1699 1700 if (sk->sk_type != SOCK_STREAM) 1701 return -ENOPROTOOPT; 1702 1703 msg.msg_control_is_user = true; 1704 msg.msg_control_user = optval; 1705 msg.msg_controllen = len; 1706 msg.msg_flags = in_compat_syscall() ? MSG_CMSG_COMPAT : 0; 1707 1708 if (inet->cmsg_flags & IP_CMSG_PKTINFO) { 1709 struct in_pktinfo info; 1710 1711 info.ipi_addr.s_addr = inet->inet_rcv_saddr; 1712 info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr; 1713 info.ipi_ifindex = inet->mc_index; 1714 put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info); 1715 } 1716 if (inet->cmsg_flags & IP_CMSG_TTL) { 1717 int hlim = inet->mc_ttl; 1718 put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim); 1719 } 1720 if (inet->cmsg_flags & IP_CMSG_TOS) { 1721 int tos = inet->rcv_tos; 1722 put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos); 1723 } 1724 len -= msg.msg_controllen; 1725 return put_user(len, optlen); 1726 } 1727 case IP_FREEBIND: 1728 val = inet->freebind; 1729 break; 1730 case IP_TRANSPARENT: 1731 val = inet->transparent; 1732 break; 1733 case IP_MINTTL: 1734 val = inet->min_ttl; 1735 break; 1736 default: 1737 release_sock(sk); 1738 return -ENOPROTOOPT; 1739 } 1740 release_sock(sk); 1741 1742 if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) { 1743 unsigned char ucval = (unsigned char)val; 1744 len = 1; 1745 if (put_user(len, optlen)) 1746 return -EFAULT; 1747 if (copy_to_user(optval, &ucval, 1)) 1748 return -EFAULT; 1749 } else { 1750 len = min_t(unsigned int, sizeof(int), len); 1751 if (put_user(len, optlen)) 1752 return -EFAULT; 1753 if (copy_to_user(optval, &val, len)) 1754 return -EFAULT; 1755 } 1756 return 0; 1757 1758 out: 1759 release_sock(sk); 1760 if (needs_rtnl) 1761 rtnl_unlock(); 1762 return err; 1763 } 1764 1765 int ip_getsockopt(struct sock *sk, int level, 1766 int optname, char __user *optval, int __user *optlen) 1767 { 1768 int err; 1769 1770 err = do_ip_getsockopt(sk, level, optname, optval, optlen); 1771 1772 #if IS_ENABLED(CONFIG_BPFILTER_UMH) 1773 if (optname >= BPFILTER_IPT_SO_GET_INFO && 1774 optname < BPFILTER_IPT_GET_MAX) 1775 err = bpfilter_ip_get_sockopt(sk, optname, optval, optlen); 1776 #endif 1777 #ifdef CONFIG_NETFILTER 1778 /* we need to exclude all possible ENOPROTOOPTs except default case */ 1779 if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS && 1780 !ip_mroute_opt(optname)) { 1781 int len; 1782 1783 if (get_user(len, optlen)) 1784 return -EFAULT; 1785 1786 err = nf_getsockopt(sk, PF_INET, optname, optval, &len); 1787 if (err >= 0) 1788 err = put_user(len, optlen); 1789 return err; 1790 } 1791 #endif 1792 return err; 1793 } 1794 EXPORT_SYMBOL(ip_getsockopt); 1795