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(addrlen * asoc->peer.transport_count) 241 + nla_total_size(addrlen * addrcnt) 242 + nla_total_size(sizeof(struct inet_diag_msg)) 243 + inet_diag_msg_attrs_size() 244 + nla_total_size(sizeof(struct inet_diag_meminfo)) 245 + 64; 246 } 247 248 static int sctp_tsp_dump_one(struct sctp_transport *tsp, void *p) 249 { 250 struct sctp_association *assoc = tsp->asoc; 251 struct sock *sk = tsp->asoc->base.sk; 252 struct sctp_comm_param *commp = p; 253 struct sk_buff *in_skb = commp->skb; 254 const struct inet_diag_req_v2 *req = commp->r; 255 const struct nlmsghdr *nlh = commp->nlh; 256 struct net *net = sock_net(in_skb->sk); 257 struct sk_buff *rep; 258 int err; 259 260 err = sock_diag_check_cookie(sk, req->id.idiag_cookie); 261 if (err) 262 goto out; 263 264 err = -ENOMEM; 265 rep = nlmsg_new(inet_assoc_attr_size(assoc), GFP_KERNEL); 266 if (!rep) 267 goto out; 268 269 lock_sock(sk); 270 if (sk != assoc->base.sk) { 271 release_sock(sk); 272 sk = assoc->base.sk; 273 lock_sock(sk); 274 } 275 err = inet_sctp_diag_fill(sk, assoc, rep, req, 276 sk_user_ns(NETLINK_CB(in_skb).sk), 277 NETLINK_CB(in_skb).portid, 278 nlh->nlmsg_seq, 0, nlh, 279 commp->net_admin); 280 release_sock(sk); 281 if (err < 0) { 282 WARN_ON(err == -EMSGSIZE); 283 kfree_skb(rep); 284 goto out; 285 } 286 287 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, 288 MSG_DONTWAIT); 289 if (err > 0) 290 err = 0; 291 out: 292 return err; 293 } 294 295 static int sctp_sock_dump(struct sctp_transport *tsp, void *p) 296 { 297 struct sctp_endpoint *ep = tsp->asoc->ep; 298 struct sctp_comm_param *commp = p; 299 struct sock *sk = ep->base.sk; 300 struct sk_buff *skb = commp->skb; 301 struct netlink_callback *cb = commp->cb; 302 const struct inet_diag_req_v2 *r = commp->r; 303 struct sctp_association *assoc; 304 int err = 0; 305 306 lock_sock(sk); 307 list_for_each_entry(assoc, &ep->asocs, asocs) { 308 if (cb->args[4] < cb->args[1]) 309 goto next; 310 311 if (r->id.idiag_sport != htons(assoc->base.bind_addr.port) && 312 r->id.idiag_sport) 313 goto next; 314 if (r->id.idiag_dport != htons(assoc->peer.port) && 315 r->id.idiag_dport) 316 goto next; 317 318 if (!cb->args[3] && 319 inet_sctp_diag_fill(sk, NULL, skb, r, 320 sk_user_ns(NETLINK_CB(cb->skb).sk), 321 NETLINK_CB(cb->skb).portid, 322 cb->nlh->nlmsg_seq, 323 NLM_F_MULTI, cb->nlh, 324 commp->net_admin) < 0) { 325 err = 1; 326 goto release; 327 } 328 cb->args[3] = 1; 329 330 if (inet_sctp_diag_fill(sk, assoc, skb, r, 331 sk_user_ns(NETLINK_CB(cb->skb).sk), 332 NETLINK_CB(cb->skb).portid, 333 cb->nlh->nlmsg_seq, 0, cb->nlh, 334 commp->net_admin) < 0) { 335 err = 1; 336 goto release; 337 } 338 next: 339 cb->args[4]++; 340 } 341 cb->args[1] = 0; 342 cb->args[3] = 0; 343 cb->args[4] = 0; 344 release: 345 release_sock(sk); 346 return err; 347 } 348 349 static int sctp_sock_filter(struct sctp_transport *tsp, void *p) 350 { 351 struct sctp_endpoint *ep = tsp->asoc->ep; 352 struct sctp_comm_param *commp = p; 353 struct sock *sk = ep->base.sk; 354 const struct inet_diag_req_v2 *r = commp->r; 355 struct sctp_association *assoc = 356 list_entry(ep->asocs.next, struct sctp_association, asocs); 357 358 /* find the ep only once through the transports by this condition */ 359 if (tsp->asoc != assoc) 360 return 0; 361 362 if (r->sdiag_family != AF_UNSPEC && sk->sk_family != r->sdiag_family) 363 return 0; 364 365 return 1; 366 } 367 368 static int sctp_ep_dump(struct sctp_endpoint *ep, void *p) 369 { 370 struct sctp_comm_param *commp = p; 371 struct sock *sk = ep->base.sk; 372 struct sk_buff *skb = commp->skb; 373 struct netlink_callback *cb = commp->cb; 374 const struct inet_diag_req_v2 *r = commp->r; 375 struct net *net = sock_net(skb->sk); 376 struct inet_sock *inet = inet_sk(sk); 377 int err = 0; 378 379 if (!net_eq(sock_net(sk), net)) 380 goto out; 381 382 if (cb->args[4] < cb->args[1]) 383 goto next; 384 385 if (!(r->idiag_states & TCPF_LISTEN) && !list_empty(&ep->asocs)) 386 goto next; 387 388 if (r->sdiag_family != AF_UNSPEC && 389 sk->sk_family != r->sdiag_family) 390 goto next; 391 392 if (r->id.idiag_sport != inet->inet_sport && 393 r->id.idiag_sport) 394 goto next; 395 396 if (r->id.idiag_dport != inet->inet_dport && 397 r->id.idiag_dport) 398 goto next; 399 400 if (inet_sctp_diag_fill(sk, NULL, skb, r, 401 sk_user_ns(NETLINK_CB(cb->skb).sk), 402 NETLINK_CB(cb->skb).portid, 403 cb->nlh->nlmsg_seq, NLM_F_MULTI, 404 cb->nlh, commp->net_admin) < 0) { 405 err = 2; 406 goto out; 407 } 408 next: 409 cb->args[4]++; 410 out: 411 return err; 412 } 413 414 /* define the functions for sctp_diag_handler*/ 415 static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, 416 void *info) 417 { 418 struct sctp_infox *infox = (struct sctp_infox *)info; 419 420 if (infox->asoc) { 421 r->idiag_rqueue = atomic_read(&infox->asoc->rmem_alloc); 422 r->idiag_wqueue = infox->asoc->sndbuf_used; 423 } else { 424 r->idiag_rqueue = READ_ONCE(sk->sk_ack_backlog); 425 r->idiag_wqueue = READ_ONCE(sk->sk_max_ack_backlog); 426 } 427 if (infox->sctpinfo) 428 sctp_get_sctp_info(sk, infox->asoc, infox->sctpinfo); 429 } 430 431 static int sctp_diag_dump_one(struct sk_buff *in_skb, 432 const struct nlmsghdr *nlh, 433 const struct inet_diag_req_v2 *req) 434 { 435 struct net *net = sock_net(in_skb->sk); 436 union sctp_addr laddr, paddr; 437 struct sctp_comm_param commp = { 438 .skb = in_skb, 439 .r = req, 440 .nlh = nlh, 441 .net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN), 442 }; 443 444 if (req->sdiag_family == AF_INET) { 445 laddr.v4.sin_port = req->id.idiag_sport; 446 laddr.v4.sin_addr.s_addr = req->id.idiag_src[0]; 447 laddr.v4.sin_family = AF_INET; 448 449 paddr.v4.sin_port = req->id.idiag_dport; 450 paddr.v4.sin_addr.s_addr = req->id.idiag_dst[0]; 451 paddr.v4.sin_family = AF_INET; 452 } else { 453 laddr.v6.sin6_port = req->id.idiag_sport; 454 memcpy(&laddr.v6.sin6_addr, req->id.idiag_src, 455 sizeof(laddr.v6.sin6_addr)); 456 laddr.v6.sin6_family = AF_INET6; 457 458 paddr.v6.sin6_port = req->id.idiag_dport; 459 memcpy(&paddr.v6.sin6_addr, req->id.idiag_dst, 460 sizeof(paddr.v6.sin6_addr)); 461 paddr.v6.sin6_family = AF_INET6; 462 } 463 464 return sctp_transport_lookup_process(sctp_tsp_dump_one, 465 net, &laddr, &paddr, &commp); 466 } 467 468 static void sctp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 469 const struct inet_diag_req_v2 *r, struct nlattr *bc) 470 { 471 u32 idiag_states = r->idiag_states; 472 struct net *net = sock_net(skb->sk); 473 struct sctp_comm_param commp = { 474 .skb = skb, 475 .cb = cb, 476 .r = r, 477 .net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN), 478 }; 479 int pos = cb->args[2]; 480 481 /* eps hashtable dumps 482 * args: 483 * 0 : if it will traversal listen sock 484 * 1 : to record the sock pos of this time's traversal 485 * 4 : to work as a temporary variable to traversal list 486 */ 487 if (cb->args[0] == 0) { 488 if (!(idiag_states & TCPF_LISTEN)) 489 goto skip; 490 if (sctp_for_each_endpoint(sctp_ep_dump, &commp)) 491 goto done; 492 skip: 493 cb->args[0] = 1; 494 cb->args[1] = 0; 495 cb->args[4] = 0; 496 } 497 498 /* asocs by transport hashtable dump 499 * args: 500 * 1 : to record the assoc pos of this time's traversal 501 * 2 : to record the transport pos of this time's traversal 502 * 3 : to mark if we have dumped the ep info of the current asoc 503 * 4 : to work as a temporary variable to traversal list 504 * 5 : to save the sk we get from travelsing the tsp list. 505 */ 506 if (!(idiag_states & ~(TCPF_LISTEN | TCPF_CLOSE))) 507 goto done; 508 509 sctp_for_each_transport(sctp_sock_filter, sctp_sock_dump, 510 net, &pos, &commp); 511 cb->args[2] = pos; 512 513 done: 514 cb->args[1] = cb->args[4]; 515 cb->args[4] = 0; 516 } 517 518 static const struct inet_diag_handler sctp_diag_handler = { 519 .dump = sctp_diag_dump, 520 .dump_one = sctp_diag_dump_one, 521 .idiag_get_info = sctp_diag_get_info, 522 .idiag_type = IPPROTO_SCTP, 523 .idiag_info_size = sizeof(struct sctp_info), 524 }; 525 526 static int __init sctp_diag_init(void) 527 { 528 return inet_diag_register(&sctp_diag_handler); 529 } 530 531 static void __exit sctp_diag_exit(void) 532 { 533 inet_diag_unregister(&sctp_diag_handler); 534 } 535 536 module_init(sctp_diag_init); 537 module_exit(sctp_diag_exit); 538 MODULE_LICENSE("GPL"); 539 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-132); 540