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