1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* SCTP kernel implementation 3 * (C) Copyright Red Hat Inc. 2017 4 * 5 * This file is part of the SCTP kernel implementation 6 * 7 * These functions implement sctp diag support. 8 * 9 * Please send any bug reports or fixes you make to the 10 * email addresched(es): 11 * lksctp developers <linux-sctp@vger.kernel.org> 12 * 13 * Written or modified by: 14 * Xin Long <lucien.xin@gmail.com> 15 */ 16 17 #include <linux/module.h> 18 #include <linux/inet_diag.h> 19 #include <linux/sock_diag.h> 20 #include <net/sctp/sctp.h> 21 22 static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, 23 void *info); 24 25 /* define some functions to make asoc/ep fill look clean */ 26 static void inet_diag_msg_sctpasoc_fill(struct inet_diag_msg *r, 27 struct sock *sk, 28 struct sctp_association *asoc) 29 { 30 union sctp_addr laddr, paddr; 31 struct dst_entry *dst; 32 struct timer_list *t3_rtx = &asoc->peer.primary_path->T3_rtx_timer; 33 34 laddr = list_entry(asoc->base.bind_addr.address_list.next, 35 struct sctp_sockaddr_entry, list)->a; 36 paddr = asoc->peer.primary_path->ipaddr; 37 dst = asoc->peer.primary_path->dst; 38 39 r->idiag_family = sk->sk_family; 40 r->id.idiag_sport = htons(asoc->base.bind_addr.port); 41 r->id.idiag_dport = htons(asoc->peer.port); 42 r->id.idiag_if = dst ? dst->dev->ifindex : 0; 43 sock_diag_save_cookie(sk, r->id.idiag_cookie); 44 45 #if IS_ENABLED(CONFIG_IPV6) 46 if (sk->sk_family == AF_INET6) { 47 *(struct in6_addr *)r->id.idiag_src = laddr.v6.sin6_addr; 48 *(struct in6_addr *)r->id.idiag_dst = paddr.v6.sin6_addr; 49 } else 50 #endif 51 { 52 memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src)); 53 memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst)); 54 55 r->id.idiag_src[0] = laddr.v4.sin_addr.s_addr; 56 r->id.idiag_dst[0] = paddr.v4.sin_addr.s_addr; 57 } 58 59 r->idiag_state = asoc->state; 60 if (timer_pending(t3_rtx)) { 61 r->idiag_timer = SCTP_EVENT_TIMEOUT_T3_RTX; 62 r->idiag_retrans = asoc->rtx_data_chunks; 63 r->idiag_expires = jiffies_to_msecs(t3_rtx->expires - jiffies); 64 } else { 65 r->idiag_timer = 0; 66 r->idiag_retrans = 0; 67 r->idiag_expires = 0; 68 } 69 } 70 71 static int inet_diag_msg_sctpladdrs_fill(struct sk_buff *skb, 72 struct list_head *address_list) 73 { 74 struct sctp_sockaddr_entry *laddr; 75 int addrlen = sizeof(struct sockaddr_storage); 76 int addrcnt = 0; 77 struct nlattr *attr; 78 void *info = NULL; 79 80 list_for_each_entry_rcu(laddr, address_list, list) 81 addrcnt++; 82 83 attr = nla_reserve(skb, INET_DIAG_LOCALS, addrlen * addrcnt); 84 if (!attr) 85 return -EMSGSIZE; 86 87 info = nla_data(attr); 88 list_for_each_entry_rcu(laddr, address_list, list) { 89 memcpy(info, &laddr->a, sizeof(laddr->a)); 90 memset(info + sizeof(laddr->a), 0, addrlen - sizeof(laddr->a)); 91 info += addrlen; 92 } 93 94 return 0; 95 } 96 97 static int inet_diag_msg_sctpaddrs_fill(struct sk_buff *skb, 98 struct sctp_association *asoc) 99 { 100 int addrlen = sizeof(struct sockaddr_storage); 101 struct sctp_transport *from; 102 struct nlattr *attr; 103 void *info = NULL; 104 105 attr = nla_reserve(skb, INET_DIAG_PEERS, 106 addrlen * asoc->peer.transport_count); 107 if (!attr) 108 return -EMSGSIZE; 109 110 info = nla_data(attr); 111 list_for_each_entry(from, &asoc->peer.transport_addr_list, 112 transports) { 113 memcpy(info, &from->ipaddr, sizeof(from->ipaddr)); 114 memset(info + sizeof(from->ipaddr), 0, 115 addrlen - sizeof(from->ipaddr)); 116 info += addrlen; 117 } 118 119 return 0; 120 } 121 122 /* sctp asoc/ep fill*/ 123 static int inet_sctp_diag_fill(struct sock *sk, struct sctp_association *asoc, 124 struct sk_buff *skb, 125 const struct inet_diag_req_v2 *req, 126 struct user_namespace *user_ns, 127 int portid, u32 seq, u16 nlmsg_flags, 128 const struct nlmsghdr *unlh, 129 bool net_admin) 130 { 131 struct sctp_endpoint *ep = sctp_sk(sk)->ep; 132 struct list_head *addr_list; 133 struct inet_diag_msg *r; 134 struct nlmsghdr *nlh; 135 int ext = req->idiag_ext; 136 struct sctp_infox infox; 137 void *info = NULL; 138 139 nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r), 140 nlmsg_flags); 141 if (!nlh) 142 return -EMSGSIZE; 143 144 r = nlmsg_data(nlh); 145 BUG_ON(!sk_fullsock(sk)); 146 147 if (asoc) { 148 inet_diag_msg_sctpasoc_fill(r, sk, asoc); 149 } else { 150 inet_diag_msg_common_fill(r, sk); 151 r->idiag_state = sk->sk_state; 152 r->idiag_timer = 0; 153 r->idiag_retrans = 0; 154 } 155 156 if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns, net_admin)) 157 goto errout; 158 159 if (ext & (1 << (INET_DIAG_SKMEMINFO - 1))) { 160 u32 mem[SK_MEMINFO_VARS]; 161 int amt; 162 163 if (asoc && asoc->ep->sndbuf_policy) 164 amt = asoc->sndbuf_used; 165 else 166 amt = sk_wmem_alloc_get(sk); 167 mem[SK_MEMINFO_WMEM_ALLOC] = amt; 168 if (asoc && asoc->ep->rcvbuf_policy) 169 amt = atomic_read(&asoc->rmem_alloc); 170 else 171 amt = sk_rmem_alloc_get(sk); 172 mem[SK_MEMINFO_RMEM_ALLOC] = amt; 173 mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf; 174 mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf; 175 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc; 176 mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued; 177 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc); 178 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len); 179 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops); 180 181 if (nla_put(skb, INET_DIAG_SKMEMINFO, sizeof(mem), &mem) < 0) 182 goto errout; 183 } 184 185 if (ext & (1 << (INET_DIAG_INFO - 1))) { 186 struct nlattr *attr; 187 188 attr = nla_reserve_64bit(skb, INET_DIAG_INFO, 189 sizeof(struct sctp_info), 190 INET_DIAG_PAD); 191 if (!attr) 192 goto errout; 193 194 info = nla_data(attr); 195 } 196 infox.sctpinfo = (struct sctp_info *)info; 197 infox.asoc = asoc; 198 sctp_diag_get_info(sk, r, &infox); 199 200 addr_list = asoc ? &asoc->base.bind_addr.address_list 201 : &ep->base.bind_addr.address_list; 202 if (inet_diag_msg_sctpladdrs_fill(skb, addr_list)) 203 goto errout; 204 205 if (asoc && (ext & (1 << (INET_DIAG_CONG - 1)))) 206 if (nla_put_string(skb, INET_DIAG_CONG, "reno") < 0) 207 goto errout; 208 209 if (asoc && inet_diag_msg_sctpaddrs_fill(skb, asoc)) 210 goto errout; 211 212 nlmsg_end(skb, nlh); 213 return 0; 214 215 errout: 216 nlmsg_cancel(skb, nlh); 217 return -EMSGSIZE; 218 } 219 220 /* callback and param */ 221 struct sctp_comm_param { 222 struct sk_buff *skb; 223 struct netlink_callback *cb; 224 const struct inet_diag_req_v2 *r; 225 const struct nlmsghdr *nlh; 226 bool net_admin; 227 }; 228 229 static size_t inet_assoc_attr_size(struct sctp_association *asoc) 230 { 231 int addrlen = sizeof(struct sockaddr_storage); 232 int addrcnt = 0; 233 struct sctp_sockaddr_entry *laddr; 234 235 list_for_each_entry_rcu(laddr, &asoc->base.bind_addr.address_list, 236 list) 237 addrcnt++; 238 239 return nla_total_size(sizeof(struct sctp_info)) 240 + nla_total_size(1) /* INET_DIAG_SHUTDOWN */ 241 + nla_total_size(1) /* INET_DIAG_TOS */ 242 + nla_total_size(1) /* INET_DIAG_TCLASS */ 243 + nla_total_size(4) /* INET_DIAG_MARK */ 244 + nla_total_size(4) /* INET_DIAG_CLASS_ID */ 245 + nla_total_size(addrlen * asoc->peer.transport_count) 246 + nla_total_size(addrlen * addrcnt) 247 + nla_total_size(sizeof(struct inet_diag_meminfo)) 248 + nla_total_size(sizeof(struct inet_diag_msg)) 249 + 64; 250 } 251 252 static int sctp_tsp_dump_one(struct sctp_transport *tsp, void *p) 253 { 254 struct sctp_association *assoc = tsp->asoc; 255 struct sock *sk = tsp->asoc->base.sk; 256 struct sctp_comm_param *commp = p; 257 struct sk_buff *in_skb = commp->skb; 258 const struct inet_diag_req_v2 *req = commp->r; 259 const struct nlmsghdr *nlh = commp->nlh; 260 struct net *net = sock_net(in_skb->sk); 261 struct sk_buff *rep; 262 int err; 263 264 err = sock_diag_check_cookie(sk, req->id.idiag_cookie); 265 if (err) 266 goto out; 267 268 err = -ENOMEM; 269 rep = nlmsg_new(inet_assoc_attr_size(assoc), GFP_KERNEL); 270 if (!rep) 271 goto out; 272 273 lock_sock(sk); 274 if (sk != assoc->base.sk) { 275 release_sock(sk); 276 sk = assoc->base.sk; 277 lock_sock(sk); 278 } 279 err = inet_sctp_diag_fill(sk, assoc, rep, req, 280 sk_user_ns(NETLINK_CB(in_skb).sk), 281 NETLINK_CB(in_skb).portid, 282 nlh->nlmsg_seq, 0, nlh, 283 commp->net_admin); 284 release_sock(sk); 285 if (err < 0) { 286 WARN_ON(err == -EMSGSIZE); 287 kfree_skb(rep); 288 goto out; 289 } 290 291 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, 292 MSG_DONTWAIT); 293 if (err > 0) 294 err = 0; 295 out: 296 return err; 297 } 298 299 static int sctp_sock_dump(struct sctp_transport *tsp, void *p) 300 { 301 struct sctp_endpoint *ep = tsp->asoc->ep; 302 struct sctp_comm_param *commp = p; 303 struct sock *sk = ep->base.sk; 304 struct sk_buff *skb = commp->skb; 305 struct netlink_callback *cb = commp->cb; 306 const struct inet_diag_req_v2 *r = commp->r; 307 struct sctp_association *assoc; 308 int err = 0; 309 310 lock_sock(sk); 311 list_for_each_entry(assoc, &ep->asocs, asocs) { 312 if (cb->args[4] < cb->args[1]) 313 goto next; 314 315 if (r->id.idiag_sport != htons(assoc->base.bind_addr.port) && 316 r->id.idiag_sport) 317 goto next; 318 if (r->id.idiag_dport != htons(assoc->peer.port) && 319 r->id.idiag_dport) 320 goto next; 321 322 if (!cb->args[3] && 323 inet_sctp_diag_fill(sk, NULL, skb, r, 324 sk_user_ns(NETLINK_CB(cb->skb).sk), 325 NETLINK_CB(cb->skb).portid, 326 cb->nlh->nlmsg_seq, 327 NLM_F_MULTI, cb->nlh, 328 commp->net_admin) < 0) { 329 err = 1; 330 goto release; 331 } 332 cb->args[3] = 1; 333 334 if (inet_sctp_diag_fill(sk, assoc, skb, r, 335 sk_user_ns(NETLINK_CB(cb->skb).sk), 336 NETLINK_CB(cb->skb).portid, 337 cb->nlh->nlmsg_seq, 0, cb->nlh, 338 commp->net_admin) < 0) { 339 err = 1; 340 goto release; 341 } 342 next: 343 cb->args[4]++; 344 } 345 cb->args[1] = 0; 346 cb->args[3] = 0; 347 cb->args[4] = 0; 348 release: 349 release_sock(sk); 350 return err; 351 } 352 353 static int sctp_sock_filter(struct sctp_transport *tsp, void *p) 354 { 355 struct sctp_endpoint *ep = tsp->asoc->ep; 356 struct sctp_comm_param *commp = p; 357 struct sock *sk = ep->base.sk; 358 const struct inet_diag_req_v2 *r = commp->r; 359 struct sctp_association *assoc = 360 list_entry(ep->asocs.next, struct sctp_association, asocs); 361 362 /* find the ep only once through the transports by this condition */ 363 if (tsp->asoc != assoc) 364 return 0; 365 366 if (r->sdiag_family != AF_UNSPEC && sk->sk_family != r->sdiag_family) 367 return 0; 368 369 return 1; 370 } 371 372 static int sctp_ep_dump(struct sctp_endpoint *ep, void *p) 373 { 374 struct sctp_comm_param *commp = p; 375 struct sock *sk = ep->base.sk; 376 struct sk_buff *skb = commp->skb; 377 struct netlink_callback *cb = commp->cb; 378 const struct inet_diag_req_v2 *r = commp->r; 379 struct net *net = sock_net(skb->sk); 380 struct inet_sock *inet = inet_sk(sk); 381 int err = 0; 382 383 if (!net_eq(sock_net(sk), net)) 384 goto out; 385 386 if (cb->args[4] < cb->args[1]) 387 goto next; 388 389 if (!(r->idiag_states & TCPF_LISTEN) && !list_empty(&ep->asocs)) 390 goto next; 391 392 if (r->sdiag_family != AF_UNSPEC && 393 sk->sk_family != r->sdiag_family) 394 goto next; 395 396 if (r->id.idiag_sport != inet->inet_sport && 397 r->id.idiag_sport) 398 goto next; 399 400 if (r->id.idiag_dport != inet->inet_dport && 401 r->id.idiag_dport) 402 goto next; 403 404 if (inet_sctp_diag_fill(sk, NULL, skb, r, 405 sk_user_ns(NETLINK_CB(cb->skb).sk), 406 NETLINK_CB(cb->skb).portid, 407 cb->nlh->nlmsg_seq, NLM_F_MULTI, 408 cb->nlh, commp->net_admin) < 0) { 409 err = 2; 410 goto out; 411 } 412 next: 413 cb->args[4]++; 414 out: 415 return err; 416 } 417 418 /* define the functions for sctp_diag_handler*/ 419 static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, 420 void *info) 421 { 422 struct sctp_infox *infox = (struct sctp_infox *)info; 423 424 if (infox->asoc) { 425 r->idiag_rqueue = atomic_read(&infox->asoc->rmem_alloc); 426 r->idiag_wqueue = infox->asoc->sndbuf_used; 427 } else { 428 r->idiag_rqueue = READ_ONCE(sk->sk_ack_backlog); 429 r->idiag_wqueue = READ_ONCE(sk->sk_max_ack_backlog); 430 } 431 if (infox->sctpinfo) 432 sctp_get_sctp_info(sk, infox->asoc, infox->sctpinfo); 433 } 434 435 static int sctp_diag_dump_one(struct sk_buff *in_skb, 436 const struct nlmsghdr *nlh, 437 const struct inet_diag_req_v2 *req) 438 { 439 struct net *net = sock_net(in_skb->sk); 440 union sctp_addr laddr, paddr; 441 struct sctp_comm_param commp = { 442 .skb = in_skb, 443 .r = req, 444 .nlh = nlh, 445 .net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN), 446 }; 447 448 if (req->sdiag_family == AF_INET) { 449 laddr.v4.sin_port = req->id.idiag_sport; 450 laddr.v4.sin_addr.s_addr = req->id.idiag_src[0]; 451 laddr.v4.sin_family = AF_INET; 452 453 paddr.v4.sin_port = req->id.idiag_dport; 454 paddr.v4.sin_addr.s_addr = req->id.idiag_dst[0]; 455 paddr.v4.sin_family = AF_INET; 456 } else { 457 laddr.v6.sin6_port = req->id.idiag_sport; 458 memcpy(&laddr.v6.sin6_addr, req->id.idiag_src, 459 sizeof(laddr.v6.sin6_addr)); 460 laddr.v6.sin6_family = AF_INET6; 461 462 paddr.v6.sin6_port = req->id.idiag_dport; 463 memcpy(&paddr.v6.sin6_addr, req->id.idiag_dst, 464 sizeof(paddr.v6.sin6_addr)); 465 paddr.v6.sin6_family = AF_INET6; 466 } 467 468 return sctp_transport_lookup_process(sctp_tsp_dump_one, 469 net, &laddr, &paddr, &commp); 470 } 471 472 static void sctp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 473 const struct inet_diag_req_v2 *r, struct nlattr *bc) 474 { 475 u32 idiag_states = r->idiag_states; 476 struct net *net = sock_net(skb->sk); 477 struct sctp_comm_param commp = { 478 .skb = skb, 479 .cb = cb, 480 .r = r, 481 .net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN), 482 }; 483 int pos = cb->args[2]; 484 485 /* eps hashtable dumps 486 * args: 487 * 0 : if it will traversal listen sock 488 * 1 : to record the sock pos of this time's traversal 489 * 4 : to work as a temporary variable to traversal list 490 */ 491 if (cb->args[0] == 0) { 492 if (!(idiag_states & TCPF_LISTEN)) 493 goto skip; 494 if (sctp_for_each_endpoint(sctp_ep_dump, &commp)) 495 goto done; 496 skip: 497 cb->args[0] = 1; 498 cb->args[1] = 0; 499 cb->args[4] = 0; 500 } 501 502 /* asocs by transport hashtable dump 503 * args: 504 * 1 : to record the assoc pos of this time's traversal 505 * 2 : to record the transport pos of this time's traversal 506 * 3 : to mark if we have dumped the ep info of the current asoc 507 * 4 : to work as a temporary variable to traversal list 508 * 5 : to save the sk we get from travelsing the tsp list. 509 */ 510 if (!(idiag_states & ~(TCPF_LISTEN | TCPF_CLOSE))) 511 goto done; 512 513 sctp_for_each_transport(sctp_sock_filter, sctp_sock_dump, 514 net, &pos, &commp); 515 cb->args[2] = pos; 516 517 done: 518 cb->args[1] = cb->args[4]; 519 cb->args[4] = 0; 520 } 521 522 static const struct inet_diag_handler sctp_diag_handler = { 523 .dump = sctp_diag_dump, 524 .dump_one = sctp_diag_dump_one, 525 .idiag_get_info = sctp_diag_get_info, 526 .idiag_type = IPPROTO_SCTP, 527 .idiag_info_size = sizeof(struct sctp_info), 528 }; 529 530 static int __init sctp_diag_init(void) 531 { 532 return inet_diag_register(&sctp_diag_handler); 533 } 534 535 static void __exit sctp_diag_exit(void) 536 { 537 inet_diag_unregister(&sctp_diag_handler); 538 } 539 540 module_init(sctp_diag_init); 541 module_exit(sctp_diag_exit); 542 MODULE_LICENSE("GPL"); 543 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-132); 544