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, 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 EXPORT_SYMBOL_GPL(ip_icmp_error); 437 438 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info) 439 { 440 struct inet_sock *inet = inet_sk(sk); 441 struct sock_exterr_skb *serr; 442 struct iphdr *iph; 443 struct sk_buff *skb; 444 445 if (!inet->recverr) 446 return; 447 448 skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC); 449 if (!skb) 450 return; 451 452 skb_put(skb, sizeof(struct iphdr)); 453 skb_reset_network_header(skb); 454 iph = ip_hdr(skb); 455 iph->daddr = daddr; 456 457 serr = SKB_EXT_ERR(skb); 458 serr->ee.ee_errno = err; 459 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; 460 serr->ee.ee_type = 0; 461 serr->ee.ee_code = 0; 462 serr->ee.ee_pad = 0; 463 serr->ee.ee_info = info; 464 serr->ee.ee_data = 0; 465 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb); 466 serr->port = port; 467 468 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 469 skb_reset_transport_header(skb); 470 471 if (sock_queue_err_skb(sk, skb)) 472 kfree_skb(skb); 473 } 474 475 /* For some errors we have valid addr_offset even with zero payload and 476 * zero port. Also, addr_offset should be supported if port is set. 477 */ 478 static inline bool ipv4_datagram_support_addr(struct sock_exterr_skb *serr) 479 { 480 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP || 481 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port; 482 } 483 484 /* IPv4 supports cmsg on all imcp errors and some timestamps 485 * 486 * Timestamp code paths do not initialize the fields expected by cmsg: 487 * the PKTINFO fields in skb->cb[]. Fill those in here. 488 */ 489 static bool ipv4_datagram_support_cmsg(const struct sock *sk, 490 struct sk_buff *skb, 491 int ee_origin) 492 { 493 struct in_pktinfo *info; 494 495 if (ee_origin == SO_EE_ORIGIN_ICMP) 496 return true; 497 498 if (ee_origin == SO_EE_ORIGIN_LOCAL) 499 return false; 500 501 /* Support IP_PKTINFO on tstamp packets if requested, to correlate 502 * timestamp with egress dev. Not possible for packets without iif 503 * or without payload (SOF_TIMESTAMPING_OPT_TSONLY). 504 */ 505 info = PKTINFO_SKB_CB(skb); 506 if (!(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_CMSG) || 507 !info->ipi_ifindex) 508 return false; 509 510 info->ipi_spec_dst.s_addr = ip_hdr(skb)->saddr; 511 return true; 512 } 513 514 /* 515 * Handle MSG_ERRQUEUE 516 */ 517 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) 518 { 519 struct sock_exterr_skb *serr; 520 struct sk_buff *skb; 521 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name); 522 struct { 523 struct sock_extended_err ee; 524 struct sockaddr_in offender; 525 } errhdr; 526 int err; 527 int copied; 528 529 err = -EAGAIN; 530 skb = sock_dequeue_err_skb(sk); 531 if (!skb) 532 goto out; 533 534 copied = skb->len; 535 if (copied > len) { 536 msg->msg_flags |= MSG_TRUNC; 537 copied = len; 538 } 539 err = skb_copy_datagram_msg(skb, 0, msg, copied); 540 if (unlikely(err)) { 541 kfree_skb(skb); 542 return err; 543 } 544 sock_recv_timestamp(msg, sk, skb); 545 546 serr = SKB_EXT_ERR(skb); 547 548 if (sin && ipv4_datagram_support_addr(serr)) { 549 sin->sin_family = AF_INET; 550 sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) + 551 serr->addr_offset); 552 sin->sin_port = serr->port; 553 memset(&sin->sin_zero, 0, sizeof(sin->sin_zero)); 554 *addr_len = sizeof(*sin); 555 } 556 557 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err)); 558 sin = &errhdr.offender; 559 memset(sin, 0, sizeof(*sin)); 560 561 if (ipv4_datagram_support_cmsg(sk, skb, serr->ee.ee_origin)) { 562 sin->sin_family = AF_INET; 563 sin->sin_addr.s_addr = ip_hdr(skb)->saddr; 564 if (inet_sk(sk)->cmsg_flags) 565 ip_cmsg_recv(msg, skb); 566 } 567 568 put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr); 569 570 /* Now we could try to dump offended packet options */ 571 572 msg->msg_flags |= MSG_ERRQUEUE; 573 err = copied; 574 575 consume_skb(skb); 576 out: 577 return err; 578 } 579 580 void __ip_sock_set_tos(struct sock *sk, int val) 581 { 582 if (sk->sk_type == SOCK_STREAM) { 583 val &= ~INET_ECN_MASK; 584 val |= inet_sk(sk)->tos & INET_ECN_MASK; 585 } 586 if (inet_sk(sk)->tos != val) { 587 inet_sk(sk)->tos = val; 588 sk->sk_priority = rt_tos2priority(val); 589 sk_dst_reset(sk); 590 } 591 } 592 593 void ip_sock_set_tos(struct sock *sk, int val) 594 { 595 lock_sock(sk); 596 __ip_sock_set_tos(sk, val); 597 release_sock(sk); 598 } 599 EXPORT_SYMBOL(ip_sock_set_tos); 600 601 void ip_sock_set_freebind(struct sock *sk) 602 { 603 lock_sock(sk); 604 inet_sk(sk)->freebind = true; 605 release_sock(sk); 606 } 607 EXPORT_SYMBOL(ip_sock_set_freebind); 608 609 void ip_sock_set_recverr(struct sock *sk) 610 { 611 lock_sock(sk); 612 inet_sk(sk)->recverr = true; 613 release_sock(sk); 614 } 615 EXPORT_SYMBOL(ip_sock_set_recverr); 616 617 int ip_sock_set_mtu_discover(struct sock *sk, int val) 618 { 619 if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT) 620 return -EINVAL; 621 lock_sock(sk); 622 inet_sk(sk)->pmtudisc = val; 623 release_sock(sk); 624 return 0; 625 } 626 EXPORT_SYMBOL(ip_sock_set_mtu_discover); 627 628 void ip_sock_set_pktinfo(struct sock *sk) 629 { 630 lock_sock(sk); 631 inet_sk(sk)->cmsg_flags |= IP_CMSG_PKTINFO; 632 release_sock(sk); 633 } 634 EXPORT_SYMBOL(ip_sock_set_pktinfo); 635 636 /* 637 * Socket option code for IP. This is the end of the line after any 638 * TCP,UDP etc options on an IP socket. 639 */ 640 static bool setsockopt_needs_rtnl(int optname) 641 { 642 switch (optname) { 643 case IP_ADD_MEMBERSHIP: 644 case IP_ADD_SOURCE_MEMBERSHIP: 645 case IP_BLOCK_SOURCE: 646 case IP_DROP_MEMBERSHIP: 647 case IP_DROP_SOURCE_MEMBERSHIP: 648 case IP_MSFILTER: 649 case IP_UNBLOCK_SOURCE: 650 case MCAST_BLOCK_SOURCE: 651 case MCAST_MSFILTER: 652 case MCAST_JOIN_GROUP: 653 case MCAST_JOIN_SOURCE_GROUP: 654 case MCAST_LEAVE_GROUP: 655 case MCAST_LEAVE_SOURCE_GROUP: 656 case MCAST_UNBLOCK_SOURCE: 657 return true; 658 } 659 return false; 660 } 661 662 static int set_mcast_msfilter(struct sock *sk, int ifindex, 663 int numsrc, int fmode, 664 struct sockaddr_storage *group, 665 struct sockaddr_storage *list) 666 { 667 struct ip_msfilter *msf; 668 struct sockaddr_in *psin; 669 int err, i; 670 671 msf = kmalloc(IP_MSFILTER_SIZE(numsrc), GFP_KERNEL); 672 if (!msf) 673 return -ENOBUFS; 674 675 psin = (struct sockaddr_in *)group; 676 if (psin->sin_family != AF_INET) 677 goto Eaddrnotavail; 678 msf->imsf_multiaddr = psin->sin_addr.s_addr; 679 msf->imsf_interface = 0; 680 msf->imsf_fmode = fmode; 681 msf->imsf_numsrc = numsrc; 682 for (i = 0; i < numsrc; ++i) { 683 psin = (struct sockaddr_in *)&list[i]; 684 685 if (psin->sin_family != AF_INET) 686 goto Eaddrnotavail; 687 msf->imsf_slist_flex[i] = psin->sin_addr.s_addr; 688 } 689 err = ip_mc_msfilter(sk, msf, ifindex); 690 kfree(msf); 691 return err; 692 693 Eaddrnotavail: 694 kfree(msf); 695 return -EADDRNOTAVAIL; 696 } 697 698 static int copy_group_source_from_sockptr(struct group_source_req *greqs, 699 sockptr_t optval, int optlen) 700 { 701 if (in_compat_syscall()) { 702 struct compat_group_source_req gr32; 703 704 if (optlen != sizeof(gr32)) 705 return -EINVAL; 706 if (copy_from_sockptr(&gr32, optval, sizeof(gr32))) 707 return -EFAULT; 708 greqs->gsr_interface = gr32.gsr_interface; 709 greqs->gsr_group = gr32.gsr_group; 710 greqs->gsr_source = gr32.gsr_source; 711 } else { 712 if (optlen != sizeof(*greqs)) 713 return -EINVAL; 714 if (copy_from_sockptr(greqs, optval, sizeof(*greqs))) 715 return -EFAULT; 716 } 717 718 return 0; 719 } 720 721 static int do_mcast_group_source(struct sock *sk, int optname, 722 sockptr_t optval, int optlen) 723 { 724 struct group_source_req greqs; 725 struct ip_mreq_source mreqs; 726 struct sockaddr_in *psin; 727 int omode, add, err; 728 729 err = copy_group_source_from_sockptr(&greqs, optval, optlen); 730 if (err) 731 return err; 732 733 if (greqs.gsr_group.ss_family != AF_INET || 734 greqs.gsr_source.ss_family != AF_INET) 735 return -EADDRNOTAVAIL; 736 737 psin = (struct sockaddr_in *)&greqs.gsr_group; 738 mreqs.imr_multiaddr = psin->sin_addr.s_addr; 739 psin = (struct sockaddr_in *)&greqs.gsr_source; 740 mreqs.imr_sourceaddr = psin->sin_addr.s_addr; 741 mreqs.imr_interface = 0; /* use index for mc_source */ 742 743 if (optname == MCAST_BLOCK_SOURCE) { 744 omode = MCAST_EXCLUDE; 745 add = 1; 746 } else if (optname == MCAST_UNBLOCK_SOURCE) { 747 omode = MCAST_EXCLUDE; 748 add = 0; 749 } else if (optname == MCAST_JOIN_SOURCE_GROUP) { 750 struct ip_mreqn mreq; 751 752 psin = (struct sockaddr_in *)&greqs.gsr_group; 753 mreq.imr_multiaddr = psin->sin_addr; 754 mreq.imr_address.s_addr = 0; 755 mreq.imr_ifindex = greqs.gsr_interface; 756 err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE); 757 if (err && err != -EADDRINUSE) 758 return err; 759 greqs.gsr_interface = mreq.imr_ifindex; 760 omode = MCAST_INCLUDE; 761 add = 1; 762 } else /* MCAST_LEAVE_SOURCE_GROUP */ { 763 omode = MCAST_INCLUDE; 764 add = 0; 765 } 766 return ip_mc_source(add, omode, sk, &mreqs, greqs.gsr_interface); 767 } 768 769 static int ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval, int optlen) 770 { 771 struct group_filter *gsf = NULL; 772 int err; 773 774 if (optlen < GROUP_FILTER_SIZE(0)) 775 return -EINVAL; 776 if (optlen > READ_ONCE(sysctl_optmem_max)) 777 return -ENOBUFS; 778 779 gsf = memdup_sockptr(optval, optlen); 780 if (IS_ERR(gsf)) 781 return PTR_ERR(gsf); 782 783 /* numsrc >= (4G-140)/128 overflow in 32 bits */ 784 err = -ENOBUFS; 785 if (gsf->gf_numsrc >= 0x1ffffff || 786 gsf->gf_numsrc > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf)) 787 goto out_free_gsf; 788 789 err = -EINVAL; 790 if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) 791 goto out_free_gsf; 792 793 err = set_mcast_msfilter(sk, gsf->gf_interface, gsf->gf_numsrc, 794 gsf->gf_fmode, &gsf->gf_group, 795 gsf->gf_slist_flex); 796 out_free_gsf: 797 kfree(gsf); 798 return err; 799 } 800 801 static int compat_ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval, 802 int optlen) 803 { 804 const int size0 = offsetof(struct compat_group_filter, gf_slist_flex); 805 struct compat_group_filter *gf32; 806 unsigned int n; 807 void *p; 808 int err; 809 810 if (optlen < size0) 811 return -EINVAL; 812 if (optlen > READ_ONCE(sysctl_optmem_max) - 4) 813 return -ENOBUFS; 814 815 p = kmalloc(optlen + 4, GFP_KERNEL); 816 if (!p) 817 return -ENOMEM; 818 gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */ 819 820 err = -EFAULT; 821 if (copy_from_sockptr(gf32, optval, optlen)) 822 goto out_free_gsf; 823 824 /* numsrc >= (4G-140)/128 overflow in 32 bits */ 825 n = gf32->gf_numsrc; 826 err = -ENOBUFS; 827 if (n >= 0x1ffffff) 828 goto out_free_gsf; 829 830 err = -EINVAL; 831 if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen) 832 goto out_free_gsf; 833 834 /* numsrc >= (4G-140)/128 overflow in 32 bits */ 835 err = -ENOBUFS; 836 if (n > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf)) 837 goto out_free_gsf; 838 err = set_mcast_msfilter(sk, gf32->gf_interface, n, gf32->gf_fmode, 839 &gf32->gf_group, gf32->gf_slist_flex); 840 out_free_gsf: 841 kfree(p); 842 return err; 843 } 844 845 static int ip_mcast_join_leave(struct sock *sk, int optname, 846 sockptr_t optval, int optlen) 847 { 848 struct ip_mreqn mreq = { }; 849 struct sockaddr_in *psin; 850 struct group_req greq; 851 852 if (optlen < sizeof(struct group_req)) 853 return -EINVAL; 854 if (copy_from_sockptr(&greq, optval, sizeof(greq))) 855 return -EFAULT; 856 857 psin = (struct sockaddr_in *)&greq.gr_group; 858 if (psin->sin_family != AF_INET) 859 return -EINVAL; 860 mreq.imr_multiaddr = psin->sin_addr; 861 mreq.imr_ifindex = greq.gr_interface; 862 if (optname == MCAST_JOIN_GROUP) 863 return ip_mc_join_group(sk, &mreq); 864 return ip_mc_leave_group(sk, &mreq); 865 } 866 867 static int compat_ip_mcast_join_leave(struct sock *sk, int optname, 868 sockptr_t optval, int optlen) 869 { 870 struct compat_group_req greq; 871 struct ip_mreqn mreq = { }; 872 struct sockaddr_in *psin; 873 874 if (optlen < sizeof(struct compat_group_req)) 875 return -EINVAL; 876 if (copy_from_sockptr(&greq, optval, sizeof(greq))) 877 return -EFAULT; 878 879 psin = (struct sockaddr_in *)&greq.gr_group; 880 if (psin->sin_family != AF_INET) 881 return -EINVAL; 882 mreq.imr_multiaddr = psin->sin_addr; 883 mreq.imr_ifindex = greq.gr_interface; 884 885 if (optname == MCAST_JOIN_GROUP) 886 return ip_mc_join_group(sk, &mreq); 887 return ip_mc_leave_group(sk, &mreq); 888 } 889 890 DEFINE_STATIC_KEY_FALSE(ip4_min_ttl); 891 892 int do_ip_setsockopt(struct sock *sk, int level, int optname, 893 sockptr_t optval, unsigned int optlen) 894 { 895 struct inet_sock *inet = inet_sk(sk); 896 struct net *net = sock_net(sk); 897 int val = 0, err; 898 bool needs_rtnl = setsockopt_needs_rtnl(optname); 899 900 switch (optname) { 901 case IP_PKTINFO: 902 case IP_RECVTTL: 903 case IP_RECVOPTS: 904 case IP_RECVTOS: 905 case IP_RETOPTS: 906 case IP_TOS: 907 case IP_TTL: 908 case IP_HDRINCL: 909 case IP_MTU_DISCOVER: 910 case IP_RECVERR: 911 case IP_ROUTER_ALERT: 912 case IP_FREEBIND: 913 case IP_PASSSEC: 914 case IP_TRANSPARENT: 915 case IP_MINTTL: 916 case IP_NODEFRAG: 917 case IP_BIND_ADDRESS_NO_PORT: 918 case IP_UNICAST_IF: 919 case IP_MULTICAST_TTL: 920 case IP_MULTICAST_ALL: 921 case IP_MULTICAST_LOOP: 922 case IP_RECVORIGDSTADDR: 923 case IP_CHECKSUM: 924 case IP_RECVFRAGSIZE: 925 case IP_RECVERR_RFC4884: 926 if (optlen >= sizeof(int)) { 927 if (copy_from_sockptr(&val, optval, sizeof(val))) 928 return -EFAULT; 929 } else if (optlen >= sizeof(char)) { 930 unsigned char ucval; 931 932 if (copy_from_sockptr(&ucval, optval, sizeof(ucval))) 933 return -EFAULT; 934 val = (int) ucval; 935 } 936 } 937 938 /* If optlen==0, it is equivalent to val == 0 */ 939 940 if (optname == IP_ROUTER_ALERT) 941 return ip_ra_control(sk, val ? 1 : 0, NULL); 942 if (ip_mroute_opt(optname)) 943 return ip_mroute_setsockopt(sk, optname, optval, optlen); 944 945 err = 0; 946 if (needs_rtnl) 947 rtnl_lock(); 948 sockopt_lock_sock(sk); 949 950 switch (optname) { 951 case IP_OPTIONS: 952 { 953 struct ip_options_rcu *old, *opt = NULL; 954 955 if (optlen > 40) 956 goto e_inval; 957 err = ip_options_get(sock_net(sk), &opt, optval, optlen); 958 if (err) 959 break; 960 old = rcu_dereference_protected(inet->inet_opt, 961 lockdep_sock_is_held(sk)); 962 if (inet->is_icsk) { 963 struct inet_connection_sock *icsk = inet_csk(sk); 964 #if IS_ENABLED(CONFIG_IPV6) 965 if (sk->sk_family == PF_INET || 966 (!((1 << sk->sk_state) & 967 (TCPF_LISTEN | TCPF_CLOSE)) && 968 inet->inet_daddr != LOOPBACK4_IPV6)) { 969 #endif 970 if (old) 971 icsk->icsk_ext_hdr_len -= old->opt.optlen; 972 if (opt) 973 icsk->icsk_ext_hdr_len += opt->opt.optlen; 974 icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie); 975 #if IS_ENABLED(CONFIG_IPV6) 976 } 977 #endif 978 } 979 rcu_assign_pointer(inet->inet_opt, opt); 980 if (old) 981 kfree_rcu(old, rcu); 982 break; 983 } 984 case IP_PKTINFO: 985 if (val) 986 inet->cmsg_flags |= IP_CMSG_PKTINFO; 987 else 988 inet->cmsg_flags &= ~IP_CMSG_PKTINFO; 989 break; 990 case IP_RECVTTL: 991 if (val) 992 inet->cmsg_flags |= IP_CMSG_TTL; 993 else 994 inet->cmsg_flags &= ~IP_CMSG_TTL; 995 break; 996 case IP_RECVTOS: 997 if (val) 998 inet->cmsg_flags |= IP_CMSG_TOS; 999 else 1000 inet->cmsg_flags &= ~IP_CMSG_TOS; 1001 break; 1002 case IP_RECVOPTS: 1003 if (val) 1004 inet->cmsg_flags |= IP_CMSG_RECVOPTS; 1005 else 1006 inet->cmsg_flags &= ~IP_CMSG_RECVOPTS; 1007 break; 1008 case IP_RETOPTS: 1009 if (val) 1010 inet->cmsg_flags |= IP_CMSG_RETOPTS; 1011 else 1012 inet->cmsg_flags &= ~IP_CMSG_RETOPTS; 1013 break; 1014 case IP_PASSSEC: 1015 if (val) 1016 inet->cmsg_flags |= IP_CMSG_PASSSEC; 1017 else 1018 inet->cmsg_flags &= ~IP_CMSG_PASSSEC; 1019 break; 1020 case IP_RECVORIGDSTADDR: 1021 if (val) 1022 inet->cmsg_flags |= IP_CMSG_ORIGDSTADDR; 1023 else 1024 inet->cmsg_flags &= ~IP_CMSG_ORIGDSTADDR; 1025 break; 1026 case IP_CHECKSUM: 1027 if (val) { 1028 if (!(inet->cmsg_flags & IP_CMSG_CHECKSUM)) { 1029 inet_inc_convert_csum(sk); 1030 inet->cmsg_flags |= IP_CMSG_CHECKSUM; 1031 } 1032 } else { 1033 if (inet->cmsg_flags & IP_CMSG_CHECKSUM) { 1034 inet_dec_convert_csum(sk); 1035 inet->cmsg_flags &= ~IP_CMSG_CHECKSUM; 1036 } 1037 } 1038 break; 1039 case IP_RECVFRAGSIZE: 1040 if (sk->sk_type != SOCK_RAW && sk->sk_type != SOCK_DGRAM) 1041 goto e_inval; 1042 if (val) 1043 inet->cmsg_flags |= IP_CMSG_RECVFRAGSIZE; 1044 else 1045 inet->cmsg_flags &= ~IP_CMSG_RECVFRAGSIZE; 1046 break; 1047 case IP_TOS: /* This sets both TOS and Precedence */ 1048 __ip_sock_set_tos(sk, val); 1049 break; 1050 case IP_TTL: 1051 if (optlen < 1) 1052 goto e_inval; 1053 if (val != -1 && (val < 1 || val > 255)) 1054 goto e_inval; 1055 inet->uc_ttl = val; 1056 break; 1057 case IP_HDRINCL: 1058 if (sk->sk_type != SOCK_RAW) { 1059 err = -ENOPROTOOPT; 1060 break; 1061 } 1062 inet->hdrincl = val ? 1 : 0; 1063 break; 1064 case IP_NODEFRAG: 1065 if (sk->sk_type != SOCK_RAW) { 1066 err = -ENOPROTOOPT; 1067 break; 1068 } 1069 inet->nodefrag = val ? 1 : 0; 1070 break; 1071 case IP_BIND_ADDRESS_NO_PORT: 1072 inet->bind_address_no_port = val ? 1 : 0; 1073 break; 1074 case IP_MTU_DISCOVER: 1075 if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT) 1076 goto e_inval; 1077 inet->pmtudisc = val; 1078 break; 1079 case IP_RECVERR: 1080 inet->recverr = !!val; 1081 if (!val) 1082 skb_queue_purge(&sk->sk_error_queue); 1083 break; 1084 case IP_RECVERR_RFC4884: 1085 if (val < 0 || val > 1) 1086 goto e_inval; 1087 inet->recverr_rfc4884 = !!val; 1088 break; 1089 case IP_MULTICAST_TTL: 1090 if (sk->sk_type == SOCK_STREAM) 1091 goto e_inval; 1092 if (optlen < 1) 1093 goto e_inval; 1094 if (val == -1) 1095 val = 1; 1096 if (val < 0 || val > 255) 1097 goto e_inval; 1098 inet->mc_ttl = val; 1099 break; 1100 case IP_MULTICAST_LOOP: 1101 if (optlen < 1) 1102 goto e_inval; 1103 inet->mc_loop = !!val; 1104 break; 1105 case IP_UNICAST_IF: 1106 { 1107 struct net_device *dev = NULL; 1108 int ifindex; 1109 int midx; 1110 1111 if (optlen != sizeof(int)) 1112 goto e_inval; 1113 1114 ifindex = (__force int)ntohl((__force __be32)val); 1115 if (ifindex == 0) { 1116 inet->uc_index = 0; 1117 err = 0; 1118 break; 1119 } 1120 1121 dev = dev_get_by_index(sock_net(sk), ifindex); 1122 err = -EADDRNOTAVAIL; 1123 if (!dev) 1124 break; 1125 1126 midx = l3mdev_master_ifindex(dev); 1127 dev_put(dev); 1128 1129 err = -EINVAL; 1130 if (sk->sk_bound_dev_if && midx != sk->sk_bound_dev_if) 1131 break; 1132 1133 inet->uc_index = ifindex; 1134 err = 0; 1135 break; 1136 } 1137 case IP_MULTICAST_IF: 1138 { 1139 struct ip_mreqn mreq; 1140 struct net_device *dev = NULL; 1141 int midx; 1142 1143 if (sk->sk_type == SOCK_STREAM) 1144 goto e_inval; 1145 /* 1146 * Check the arguments are allowable 1147 */ 1148 1149 if (optlen < sizeof(struct in_addr)) 1150 goto e_inval; 1151 1152 err = -EFAULT; 1153 if (optlen >= sizeof(struct ip_mreqn)) { 1154 if (copy_from_sockptr(&mreq, optval, sizeof(mreq))) 1155 break; 1156 } else { 1157 memset(&mreq, 0, sizeof(mreq)); 1158 if (optlen >= sizeof(struct ip_mreq)) { 1159 if (copy_from_sockptr(&mreq, optval, 1160 sizeof(struct ip_mreq))) 1161 break; 1162 } else if (optlen >= sizeof(struct in_addr)) { 1163 if (copy_from_sockptr(&mreq.imr_address, optval, 1164 sizeof(struct in_addr))) 1165 break; 1166 } 1167 } 1168 1169 if (!mreq.imr_ifindex) { 1170 if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) { 1171 inet->mc_index = 0; 1172 inet->mc_addr = 0; 1173 err = 0; 1174 break; 1175 } 1176 dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr); 1177 if (dev) 1178 mreq.imr_ifindex = dev->ifindex; 1179 } else 1180 dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex); 1181 1182 1183 err = -EADDRNOTAVAIL; 1184 if (!dev) 1185 break; 1186 1187 midx = l3mdev_master_ifindex(dev); 1188 1189 dev_put(dev); 1190 1191 err = -EINVAL; 1192 if (sk->sk_bound_dev_if && 1193 mreq.imr_ifindex != sk->sk_bound_dev_if && 1194 midx != sk->sk_bound_dev_if) 1195 break; 1196 1197 inet->mc_index = mreq.imr_ifindex; 1198 inet->mc_addr = mreq.imr_address.s_addr; 1199 err = 0; 1200 break; 1201 } 1202 1203 case IP_ADD_MEMBERSHIP: 1204 case IP_DROP_MEMBERSHIP: 1205 { 1206 struct ip_mreqn mreq; 1207 1208 err = -EPROTO; 1209 if (inet_sk(sk)->is_icsk) 1210 break; 1211 1212 if (optlen < sizeof(struct ip_mreq)) 1213 goto e_inval; 1214 err = -EFAULT; 1215 if (optlen >= sizeof(struct ip_mreqn)) { 1216 if (copy_from_sockptr(&mreq, optval, sizeof(mreq))) 1217 break; 1218 } else { 1219 memset(&mreq, 0, sizeof(mreq)); 1220 if (copy_from_sockptr(&mreq, optval, 1221 sizeof(struct ip_mreq))) 1222 break; 1223 } 1224 1225 if (optname == IP_ADD_MEMBERSHIP) 1226 err = ip_mc_join_group(sk, &mreq); 1227 else 1228 err = ip_mc_leave_group(sk, &mreq); 1229 break; 1230 } 1231 case IP_MSFILTER: 1232 { 1233 struct ip_msfilter *msf; 1234 1235 if (optlen < IP_MSFILTER_SIZE(0)) 1236 goto e_inval; 1237 if (optlen > READ_ONCE(sysctl_optmem_max)) { 1238 err = -ENOBUFS; 1239 break; 1240 } 1241 msf = memdup_sockptr(optval, optlen); 1242 if (IS_ERR(msf)) { 1243 err = PTR_ERR(msf); 1244 break; 1245 } 1246 /* numsrc >= (1G-4) overflow in 32 bits */ 1247 if (msf->imsf_numsrc >= 0x3ffffffcU || 1248 msf->imsf_numsrc > READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) { 1249 kfree(msf); 1250 err = -ENOBUFS; 1251 break; 1252 } 1253 if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) { 1254 kfree(msf); 1255 err = -EINVAL; 1256 break; 1257 } 1258 err = ip_mc_msfilter(sk, msf, 0); 1259 kfree(msf); 1260 break; 1261 } 1262 case IP_BLOCK_SOURCE: 1263 case IP_UNBLOCK_SOURCE: 1264 case IP_ADD_SOURCE_MEMBERSHIP: 1265 case IP_DROP_SOURCE_MEMBERSHIP: 1266 { 1267 struct ip_mreq_source mreqs; 1268 int omode, add; 1269 1270 if (optlen != sizeof(struct ip_mreq_source)) 1271 goto e_inval; 1272 if (copy_from_sockptr(&mreqs, optval, sizeof(mreqs))) { 1273 err = -EFAULT; 1274 break; 1275 } 1276 if (optname == IP_BLOCK_SOURCE) { 1277 omode = MCAST_EXCLUDE; 1278 add = 1; 1279 } else if (optname == IP_UNBLOCK_SOURCE) { 1280 omode = MCAST_EXCLUDE; 1281 add = 0; 1282 } else if (optname == IP_ADD_SOURCE_MEMBERSHIP) { 1283 struct ip_mreqn mreq; 1284 1285 mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr; 1286 mreq.imr_address.s_addr = mreqs.imr_interface; 1287 mreq.imr_ifindex = 0; 1288 err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE); 1289 if (err && err != -EADDRINUSE) 1290 break; 1291 omode = MCAST_INCLUDE; 1292 add = 1; 1293 } else /* IP_DROP_SOURCE_MEMBERSHIP */ { 1294 omode = MCAST_INCLUDE; 1295 add = 0; 1296 } 1297 err = ip_mc_source(add, omode, sk, &mreqs, 0); 1298 break; 1299 } 1300 case MCAST_JOIN_GROUP: 1301 case MCAST_LEAVE_GROUP: 1302 if (in_compat_syscall()) 1303 err = compat_ip_mcast_join_leave(sk, optname, optval, 1304 optlen); 1305 else 1306 err = ip_mcast_join_leave(sk, optname, optval, optlen); 1307 break; 1308 case MCAST_JOIN_SOURCE_GROUP: 1309 case MCAST_LEAVE_SOURCE_GROUP: 1310 case MCAST_BLOCK_SOURCE: 1311 case MCAST_UNBLOCK_SOURCE: 1312 err = do_mcast_group_source(sk, optname, optval, optlen); 1313 break; 1314 case MCAST_MSFILTER: 1315 if (in_compat_syscall()) 1316 err = compat_ip_set_mcast_msfilter(sk, optval, optlen); 1317 else 1318 err = ip_set_mcast_msfilter(sk, optval, optlen); 1319 break; 1320 case IP_MULTICAST_ALL: 1321 if (optlen < 1) 1322 goto e_inval; 1323 if (val != 0 && val != 1) 1324 goto e_inval; 1325 inet->mc_all = val; 1326 break; 1327 1328 case IP_FREEBIND: 1329 if (optlen < 1) 1330 goto e_inval; 1331 inet->freebind = !!val; 1332 break; 1333 1334 case IP_IPSEC_POLICY: 1335 case IP_XFRM_POLICY: 1336 err = -EPERM; 1337 if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 1338 break; 1339 err = xfrm_user_policy(sk, optname, optval, optlen); 1340 break; 1341 1342 case IP_TRANSPARENT: 1343 if (!!val && !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) && 1344 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1345 err = -EPERM; 1346 break; 1347 } 1348 if (optlen < 1) 1349 goto e_inval; 1350 inet->transparent = !!val; 1351 break; 1352 1353 case IP_MINTTL: 1354 if (optlen < 1) 1355 goto e_inval; 1356 if (val < 0 || val > 255) 1357 goto e_inval; 1358 1359 if (val) 1360 static_branch_enable(&ip4_min_ttl); 1361 1362 /* tcp_v4_err() and tcp_v4_rcv() might read min_ttl 1363 * while we are changint it. 1364 */ 1365 WRITE_ONCE(inet->min_ttl, val); 1366 break; 1367 1368 default: 1369 err = -ENOPROTOOPT; 1370 break; 1371 } 1372 sockopt_release_sock(sk); 1373 if (needs_rtnl) 1374 rtnl_unlock(); 1375 return err; 1376 1377 e_inval: 1378 sockopt_release_sock(sk); 1379 if (needs_rtnl) 1380 rtnl_unlock(); 1381 return -EINVAL; 1382 } 1383 1384 /** 1385 * ipv4_pktinfo_prepare - transfer some info from rtable to skb 1386 * @sk: socket 1387 * @skb: buffer 1388 * 1389 * To support IP_CMSG_PKTINFO option, we store rt_iif and specific 1390 * destination in skb->cb[] before dst drop. 1391 * This way, receiver doesn't make cache line misses to read rtable. 1392 */ 1393 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb) 1394 { 1395 struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb); 1396 bool prepare = (inet_sk(sk)->cmsg_flags & IP_CMSG_PKTINFO) || 1397 ipv6_sk_rxinfo(sk); 1398 1399 if (prepare && skb_rtable(skb)) { 1400 /* skb->cb is overloaded: prior to this point it is IP{6}CB 1401 * which has interface index (iif) as the first member of the 1402 * underlying inet{6}_skb_parm struct. This code then overlays 1403 * PKTINFO_SKB_CB and in_pktinfo also has iif as the first 1404 * element so the iif is picked up from the prior IPCB. If iif 1405 * is the loopback interface, then return the sending interface 1406 * (e.g., process binds socket to eth0 for Tx which is 1407 * redirected to loopback in the rtable/dst). 1408 */ 1409 struct rtable *rt = skb_rtable(skb); 1410 bool l3slave = ipv4_l3mdev_skb(IPCB(skb)->flags); 1411 1412 if (pktinfo->ipi_ifindex == LOOPBACK_IFINDEX) 1413 pktinfo->ipi_ifindex = inet_iif(skb); 1414 else if (l3slave && rt && rt->rt_iif) 1415 pktinfo->ipi_ifindex = rt->rt_iif; 1416 1417 pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb); 1418 } else { 1419 pktinfo->ipi_ifindex = 0; 1420 pktinfo->ipi_spec_dst.s_addr = 0; 1421 } 1422 skb_dst_drop(skb); 1423 } 1424 1425 int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, 1426 unsigned int optlen) 1427 { 1428 int err; 1429 1430 if (level != SOL_IP) 1431 return -ENOPROTOOPT; 1432 1433 err = do_ip_setsockopt(sk, level, optname, optval, optlen); 1434 #if IS_ENABLED(CONFIG_BPFILTER_UMH) 1435 if (optname >= BPFILTER_IPT_SO_SET_REPLACE && 1436 optname < BPFILTER_IPT_SET_MAX) 1437 err = bpfilter_ip_set_sockopt(sk, optname, optval, optlen); 1438 #endif 1439 #ifdef CONFIG_NETFILTER 1440 /* we need to exclude all possible ENOPROTOOPTs except default case */ 1441 if (err == -ENOPROTOOPT && optname != IP_HDRINCL && 1442 optname != IP_IPSEC_POLICY && 1443 optname != IP_XFRM_POLICY && 1444 !ip_mroute_opt(optname)) 1445 err = nf_setsockopt(sk, PF_INET, optname, optval, optlen); 1446 #endif 1447 return err; 1448 } 1449 EXPORT_SYMBOL(ip_setsockopt); 1450 1451 /* 1452 * Get the options. Note for future reference. The GET of IP options gets 1453 * the _received_ ones. The set sets the _sent_ ones. 1454 */ 1455 1456 static bool getsockopt_needs_rtnl(int optname) 1457 { 1458 switch (optname) { 1459 case IP_MSFILTER: 1460 case MCAST_MSFILTER: 1461 return true; 1462 } 1463 return false; 1464 } 1465 1466 static int ip_get_mcast_msfilter(struct sock *sk, sockptr_t optval, 1467 sockptr_t optlen, int len) 1468 { 1469 const int size0 = offsetof(struct group_filter, gf_slist_flex); 1470 struct group_filter gsf; 1471 int num, gsf_size; 1472 int err; 1473 1474 if (len < size0) 1475 return -EINVAL; 1476 if (copy_from_sockptr(&gsf, optval, size0)) 1477 return -EFAULT; 1478 1479 num = gsf.gf_numsrc; 1480 err = ip_mc_gsfget(sk, &gsf, optval, 1481 offsetof(struct group_filter, gf_slist_flex)); 1482 if (err) 1483 return err; 1484 if (gsf.gf_numsrc < num) 1485 num = gsf.gf_numsrc; 1486 gsf_size = GROUP_FILTER_SIZE(num); 1487 if (copy_to_sockptr(optlen, &gsf_size, sizeof(int)) || 1488 copy_to_sockptr(optval, &gsf, size0)) 1489 return -EFAULT; 1490 return 0; 1491 } 1492 1493 static int compat_ip_get_mcast_msfilter(struct sock *sk, sockptr_t optval, 1494 sockptr_t optlen, int len) 1495 { 1496 const int size0 = offsetof(struct compat_group_filter, gf_slist_flex); 1497 struct compat_group_filter gf32; 1498 struct group_filter gf; 1499 int num; 1500 int err; 1501 1502 if (len < size0) 1503 return -EINVAL; 1504 if (copy_from_sockptr(&gf32, optval, size0)) 1505 return -EFAULT; 1506 1507 gf.gf_interface = gf32.gf_interface; 1508 gf.gf_fmode = gf32.gf_fmode; 1509 num = gf.gf_numsrc = gf32.gf_numsrc; 1510 gf.gf_group = gf32.gf_group; 1511 1512 err = ip_mc_gsfget(sk, &gf, optval, 1513 offsetof(struct compat_group_filter, gf_slist_flex)); 1514 if (err) 1515 return err; 1516 if (gf.gf_numsrc < num) 1517 num = gf.gf_numsrc; 1518 len = GROUP_FILTER_SIZE(num) - (sizeof(gf) - sizeof(gf32)); 1519 if (copy_to_sockptr(optlen, &len, sizeof(int)) || 1520 copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode), 1521 &gf.gf_fmode, sizeof(gf.gf_fmode)) || 1522 copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc), 1523 &gf.gf_numsrc, sizeof(gf.gf_numsrc))) 1524 return -EFAULT; 1525 return 0; 1526 } 1527 1528 int do_ip_getsockopt(struct sock *sk, int level, int optname, 1529 sockptr_t optval, sockptr_t optlen) 1530 { 1531 struct inet_sock *inet = inet_sk(sk); 1532 bool needs_rtnl = getsockopt_needs_rtnl(optname); 1533 int val, err = 0; 1534 int len; 1535 1536 if (level != SOL_IP) 1537 return -EOPNOTSUPP; 1538 1539 if (ip_mroute_opt(optname)) 1540 return ip_mroute_getsockopt(sk, optname, optval, optlen); 1541 1542 if (copy_from_sockptr(&len, optlen, sizeof(int))) 1543 return -EFAULT; 1544 if (len < 0) 1545 return -EINVAL; 1546 1547 if (needs_rtnl) 1548 rtnl_lock(); 1549 sockopt_lock_sock(sk); 1550 1551 switch (optname) { 1552 case IP_OPTIONS: 1553 { 1554 unsigned char optbuf[sizeof(struct ip_options)+40]; 1555 struct ip_options *opt = (struct ip_options *)optbuf; 1556 struct ip_options_rcu *inet_opt; 1557 1558 inet_opt = rcu_dereference_protected(inet->inet_opt, 1559 lockdep_sock_is_held(sk)); 1560 opt->optlen = 0; 1561 if (inet_opt) 1562 memcpy(optbuf, &inet_opt->opt, 1563 sizeof(struct ip_options) + 1564 inet_opt->opt.optlen); 1565 sockopt_release_sock(sk); 1566 1567 if (opt->optlen == 0) { 1568 len = 0; 1569 return copy_to_sockptr(optlen, &len, sizeof(int)); 1570 } 1571 1572 ip_options_undo(opt); 1573 1574 len = min_t(unsigned int, len, opt->optlen); 1575 if (copy_to_sockptr(optlen, &len, sizeof(int))) 1576 return -EFAULT; 1577 if (copy_to_sockptr(optval, opt->__data, len)) 1578 return -EFAULT; 1579 return 0; 1580 } 1581 case IP_PKTINFO: 1582 val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0; 1583 break; 1584 case IP_RECVTTL: 1585 val = (inet->cmsg_flags & IP_CMSG_TTL) != 0; 1586 break; 1587 case IP_RECVTOS: 1588 val = (inet->cmsg_flags & IP_CMSG_TOS) != 0; 1589 break; 1590 case IP_RECVOPTS: 1591 val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0; 1592 break; 1593 case IP_RETOPTS: 1594 val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0; 1595 break; 1596 case IP_PASSSEC: 1597 val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0; 1598 break; 1599 case IP_RECVORIGDSTADDR: 1600 val = (inet->cmsg_flags & IP_CMSG_ORIGDSTADDR) != 0; 1601 break; 1602 case IP_CHECKSUM: 1603 val = (inet->cmsg_flags & IP_CMSG_CHECKSUM) != 0; 1604 break; 1605 case IP_RECVFRAGSIZE: 1606 val = (inet->cmsg_flags & IP_CMSG_RECVFRAGSIZE) != 0; 1607 break; 1608 case IP_TOS: 1609 val = inet->tos; 1610 break; 1611 case IP_TTL: 1612 { 1613 struct net *net = sock_net(sk); 1614 val = (inet->uc_ttl == -1 ? 1615 READ_ONCE(net->ipv4.sysctl_ip_default_ttl) : 1616 inet->uc_ttl); 1617 break; 1618 } 1619 case IP_HDRINCL: 1620 val = inet->hdrincl; 1621 break; 1622 case IP_NODEFRAG: 1623 val = inet->nodefrag; 1624 break; 1625 case IP_BIND_ADDRESS_NO_PORT: 1626 val = inet->bind_address_no_port; 1627 break; 1628 case IP_MTU_DISCOVER: 1629 val = inet->pmtudisc; 1630 break; 1631 case IP_MTU: 1632 { 1633 struct dst_entry *dst; 1634 val = 0; 1635 dst = sk_dst_get(sk); 1636 if (dst) { 1637 val = dst_mtu(dst); 1638 dst_release(dst); 1639 } 1640 if (!val) { 1641 sockopt_release_sock(sk); 1642 return -ENOTCONN; 1643 } 1644 break; 1645 } 1646 case IP_RECVERR: 1647 val = inet->recverr; 1648 break; 1649 case IP_RECVERR_RFC4884: 1650 val = inet->recverr_rfc4884; 1651 break; 1652 case IP_MULTICAST_TTL: 1653 val = inet->mc_ttl; 1654 break; 1655 case IP_MULTICAST_LOOP: 1656 val = inet->mc_loop; 1657 break; 1658 case IP_UNICAST_IF: 1659 val = (__force int)htonl((__u32) inet->uc_index); 1660 break; 1661 case IP_MULTICAST_IF: 1662 { 1663 struct in_addr addr; 1664 len = min_t(unsigned int, len, sizeof(struct in_addr)); 1665 addr.s_addr = inet->mc_addr; 1666 sockopt_release_sock(sk); 1667 1668 if (copy_to_sockptr(optlen, &len, sizeof(int))) 1669 return -EFAULT; 1670 if (copy_to_sockptr(optval, &addr, len)) 1671 return -EFAULT; 1672 return 0; 1673 } 1674 case IP_MSFILTER: 1675 { 1676 struct ip_msfilter msf; 1677 1678 if (len < IP_MSFILTER_SIZE(0)) { 1679 err = -EINVAL; 1680 goto out; 1681 } 1682 if (copy_from_sockptr(&msf, optval, IP_MSFILTER_SIZE(0))) { 1683 err = -EFAULT; 1684 goto out; 1685 } 1686 err = ip_mc_msfget(sk, &msf, optval, optlen); 1687 goto out; 1688 } 1689 case MCAST_MSFILTER: 1690 if (in_compat_syscall()) 1691 err = compat_ip_get_mcast_msfilter(sk, optval, optlen, 1692 len); 1693 else 1694 err = ip_get_mcast_msfilter(sk, optval, optlen, len); 1695 goto out; 1696 case IP_MULTICAST_ALL: 1697 val = inet->mc_all; 1698 break; 1699 case IP_PKTOPTIONS: 1700 { 1701 struct msghdr msg; 1702 1703 sockopt_release_sock(sk); 1704 1705 if (sk->sk_type != SOCK_STREAM) 1706 return -ENOPROTOOPT; 1707 1708 if (optval.is_kernel) { 1709 msg.msg_control_is_user = false; 1710 msg.msg_control = optval.kernel; 1711 } else { 1712 msg.msg_control_is_user = true; 1713 msg.msg_control_user = optval.user; 1714 } 1715 msg.msg_controllen = len; 1716 msg.msg_flags = in_compat_syscall() ? MSG_CMSG_COMPAT : 0; 1717 1718 if (inet->cmsg_flags & IP_CMSG_PKTINFO) { 1719 struct in_pktinfo info; 1720 1721 info.ipi_addr.s_addr = inet->inet_rcv_saddr; 1722 info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr; 1723 info.ipi_ifindex = inet->mc_index; 1724 put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info); 1725 } 1726 if (inet->cmsg_flags & IP_CMSG_TTL) { 1727 int hlim = inet->mc_ttl; 1728 put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim); 1729 } 1730 if (inet->cmsg_flags & IP_CMSG_TOS) { 1731 int tos = inet->rcv_tos; 1732 put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos); 1733 } 1734 len -= msg.msg_controllen; 1735 return copy_to_sockptr(optlen, &len, sizeof(int)); 1736 } 1737 case IP_FREEBIND: 1738 val = inet->freebind; 1739 break; 1740 case IP_TRANSPARENT: 1741 val = inet->transparent; 1742 break; 1743 case IP_MINTTL: 1744 val = inet->min_ttl; 1745 break; 1746 default: 1747 sockopt_release_sock(sk); 1748 return -ENOPROTOOPT; 1749 } 1750 sockopt_release_sock(sk); 1751 1752 if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) { 1753 unsigned char ucval = (unsigned char)val; 1754 len = 1; 1755 if (copy_to_sockptr(optlen, &len, sizeof(int))) 1756 return -EFAULT; 1757 if (copy_to_sockptr(optval, &ucval, 1)) 1758 return -EFAULT; 1759 } else { 1760 len = min_t(unsigned int, sizeof(int), len); 1761 if (copy_to_sockptr(optlen, &len, sizeof(int))) 1762 return -EFAULT; 1763 if (copy_to_sockptr(optval, &val, len)) 1764 return -EFAULT; 1765 } 1766 return 0; 1767 1768 out: 1769 sockopt_release_sock(sk); 1770 if (needs_rtnl) 1771 rtnl_unlock(); 1772 return err; 1773 } 1774 1775 int ip_getsockopt(struct sock *sk, int level, 1776 int optname, char __user *optval, int __user *optlen) 1777 { 1778 int err; 1779 1780 err = do_ip_getsockopt(sk, level, optname, 1781 USER_SOCKPTR(optval), USER_SOCKPTR(optlen)); 1782 1783 #if IS_ENABLED(CONFIG_BPFILTER_UMH) 1784 if (optname >= BPFILTER_IPT_SO_GET_INFO && 1785 optname < BPFILTER_IPT_GET_MAX) 1786 err = bpfilter_ip_get_sockopt(sk, optname, optval, optlen); 1787 #endif 1788 #ifdef CONFIG_NETFILTER 1789 /* we need to exclude all possible ENOPROTOOPTs except default case */ 1790 if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS && 1791 !ip_mroute_opt(optname)) { 1792 int len; 1793 1794 if (get_user(len, optlen)) 1795 return -EFAULT; 1796 1797 err = nf_getsockopt(sk, PF_INET, optname, optval, &len); 1798 if (err >= 0) 1799 err = put_user(len, optlen); 1800 return err; 1801 } 1802 #endif 1803 return err; 1804 } 1805 EXPORT_SYMBOL(ip_getsockopt); 1806