1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * inet_diag.c Module for monitoring INET transport protocols sockets. 4 * 5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/module.h> 10 #include <linux/types.h> 11 #include <linux/fcntl.h> 12 #include <linux/random.h> 13 #include <linux/slab.h> 14 #include <linux/cache.h> 15 #include <linux/init.h> 16 #include <linux/time.h> 17 18 #include <net/icmp.h> 19 #include <net/tcp.h> 20 #include <net/ipv6.h> 21 #include <net/inet_common.h> 22 #include <net/inet_connection_sock.h> 23 #include <net/bpf_sk_storage.h> 24 #include <net/netlink.h> 25 26 #include <linux/inet.h> 27 #include <linux/stddef.h> 28 29 #include <linux/inet_diag.h> 30 #include <linux/sock_diag.h> 31 32 static const struct inet_diag_handler __rcu **inet_diag_table; 33 34 struct inet_diag_entry { 35 const __be32 *saddr; 36 const __be32 *daddr; 37 u16 sport; 38 u16 dport; 39 u16 family; 40 u16 userlocks; 41 u32 ifindex; 42 u32 mark; 43 #ifdef CONFIG_SOCK_CGROUP_DATA 44 u64 cgroup_id; 45 #endif 46 }; 47 48 static const struct inet_diag_handler *inet_diag_lock_handler(int proto) 49 { 50 const struct inet_diag_handler *handler; 51 52 if (proto < 0 || proto >= IPPROTO_MAX) 53 return NULL; 54 55 if (!READ_ONCE(inet_diag_table[proto])) 56 sock_load_diag_module(AF_INET, proto); 57 58 rcu_read_lock(); 59 handler = rcu_dereference(inet_diag_table[proto]); 60 if (handler && !try_module_get(handler->owner)) 61 handler = NULL; 62 rcu_read_unlock(); 63 64 return handler; 65 } 66 67 static void inet_diag_unlock_handler(const struct inet_diag_handler *handler) 68 { 69 module_put(handler->owner); 70 } 71 72 void inet_diag_msg_common_fill(struct inet_diag_msg *r, struct sock *sk) 73 { 74 r->idiag_family = READ_ONCE(sk->sk_family); 75 76 r->id.idiag_sport = htons(READ_ONCE(sk->sk_num)); 77 r->id.idiag_dport = READ_ONCE(sk->sk_dport); 78 r->id.idiag_if = READ_ONCE(sk->sk_bound_dev_if); 79 sock_diag_save_cookie(sk, r->id.idiag_cookie); 80 81 #if IS_ENABLED(CONFIG_IPV6) 82 if (r->idiag_family == AF_INET6) { 83 data_race(*(struct in6_addr *)r->id.idiag_src = sk->sk_v6_rcv_saddr); 84 data_race(*(struct in6_addr *)r->id.idiag_dst = sk->sk_v6_daddr); 85 } else 86 #endif 87 { 88 memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src)); 89 memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst)); 90 91 r->id.idiag_src[0] = READ_ONCE(sk->sk_rcv_saddr); 92 r->id.idiag_dst[0] = READ_ONCE(sk->sk_daddr); 93 } 94 } 95 EXPORT_SYMBOL_GPL(inet_diag_msg_common_fill); 96 97 int inet_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb, 98 struct inet_diag_msg *r, int ext, 99 struct user_namespace *user_ns, 100 bool net_admin) 101 { 102 const struct inet_sock *inet = inet_sk(sk); 103 struct inet_diag_sockopt inet_sockopt; 104 105 if (nla_put_u8(skb, INET_DIAG_SHUTDOWN, sk->sk_shutdown)) 106 goto errout; 107 108 /* IPv6 dual-stack sockets use inet->tos for IPv4 connections, 109 * hence this needs to be included regardless of socket family. 110 */ 111 if (ext & (1 << (INET_DIAG_TOS - 1))) 112 if (nla_put_u8(skb, INET_DIAG_TOS, READ_ONCE(inet->tos)) < 0) 113 goto errout; 114 115 #if IS_ENABLED(CONFIG_IPV6) 116 if (r->idiag_family == AF_INET6) { 117 if (ext & (1 << (INET_DIAG_TCLASS - 1))) 118 if (nla_put_u8(skb, INET_DIAG_TCLASS, 119 inet6_sk(sk)->tclass) < 0) 120 goto errout; 121 122 if (((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) && 123 nla_put_u8(skb, INET_DIAG_SKV6ONLY, ipv6_only_sock(sk))) 124 goto errout; 125 } 126 #endif 127 128 if (net_admin && nla_put_u32(skb, INET_DIAG_MARK, READ_ONCE(sk->sk_mark))) 129 goto errout; 130 131 if (ext & (1 << (INET_DIAG_CLASS_ID - 1)) || 132 ext & (1 << (INET_DIAG_TCLASS - 1))) { 133 u32 classid = 0; 134 135 #ifdef CONFIG_CGROUP_NET_CLASSID 136 classid = sock_cgroup_classid(&sk->sk_cgrp_data); 137 #endif 138 /* Fallback to socket priority if class id isn't set. 139 * Classful qdiscs use it as direct reference to class. 140 * For cgroup2 classid is always zero. 141 */ 142 if (!classid) 143 classid = READ_ONCE(sk->sk_priority); 144 145 if (nla_put_u32(skb, INET_DIAG_CLASS_ID, classid)) 146 goto errout; 147 } 148 149 #ifdef CONFIG_SOCK_CGROUP_DATA 150 if (nla_put_u64_64bit(skb, INET_DIAG_CGROUP_ID, 151 cgroup_id(sock_cgroup_ptr(&sk->sk_cgrp_data)), 152 INET_DIAG_PAD)) 153 goto errout; 154 #endif 155 156 r->idiag_uid = from_kuid_munged(user_ns, sk_uid(sk)); 157 r->idiag_inode = sock_i_ino(sk); 158 159 memset(&inet_sockopt, 0, sizeof(inet_sockopt)); 160 inet_sockopt.recverr = inet_test_bit(RECVERR, sk); 161 inet_sockopt.is_icsk = inet_test_bit(IS_ICSK, sk); 162 inet_sockopt.freebind = inet_test_bit(FREEBIND, sk); 163 inet_sockopt.hdrincl = inet_test_bit(HDRINCL, sk); 164 inet_sockopt.mc_loop = inet_test_bit(MC_LOOP, sk); 165 inet_sockopt.transparent = inet_test_bit(TRANSPARENT, sk); 166 inet_sockopt.mc_all = inet_test_bit(MC_ALL, sk); 167 inet_sockopt.nodefrag = inet_test_bit(NODEFRAG, sk); 168 inet_sockopt.bind_address_no_port = inet_test_bit(BIND_ADDRESS_NO_PORT, sk); 169 inet_sockopt.recverr_rfc4884 = inet_test_bit(RECVERR_RFC4884, sk); 170 inet_sockopt.defer_connect = inet_test_bit(DEFER_CONNECT, sk); 171 if (nla_put(skb, INET_DIAG_SOCKOPT, sizeof(inet_sockopt), 172 &inet_sockopt)) 173 goto errout; 174 175 return 0; 176 errout: 177 return 1; 178 } 179 EXPORT_SYMBOL_GPL(inet_diag_msg_attrs_fill); 180 181 static int inet_diag_parse_attrs(const struct nlmsghdr *nlh, int hdrlen, 182 struct nlattr **req_nlas) 183 { 184 struct nlattr *nla; 185 int remaining; 186 187 nlmsg_for_each_attr(nla, nlh, hdrlen, remaining) { 188 int type = nla_type(nla); 189 190 if (type == INET_DIAG_REQ_PROTOCOL && nla_len(nla) != sizeof(u32)) 191 return -EINVAL; 192 193 if (type < __INET_DIAG_REQ_MAX) 194 req_nlas[type] = nla; 195 } 196 return 0; 197 } 198 199 static int inet_diag_get_protocol(const struct inet_diag_req_v2 *req, 200 const struct inet_diag_dump_data *data) 201 { 202 if (data->req_nlas[INET_DIAG_REQ_PROTOCOL]) 203 return nla_get_u32(data->req_nlas[INET_DIAG_REQ_PROTOCOL]); 204 return req->sdiag_protocol; 205 } 206 207 #define MAX_DUMP_ALLOC_SIZE (KMALLOC_MAX_SIZE - SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) 208 209 int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, 210 struct sk_buff *skb, struct netlink_callback *cb, 211 const struct inet_diag_req_v2 *req, 212 u16 nlmsg_flags, bool net_admin) 213 { 214 const struct tcp_congestion_ops *ca_ops; 215 const struct inet_diag_handler *handler; 216 struct inet_diag_dump_data *cb_data; 217 int ext = req->idiag_ext; 218 struct inet_diag_msg *r; 219 struct nlmsghdr *nlh; 220 struct nlattr *attr; 221 void *info = NULL; 222 u8 icsk_pending; 223 int protocol; 224 225 cb_data = cb->data; 226 protocol = inet_diag_get_protocol(req, cb_data); 227 228 /* inet_diag_lock_handler() made sure inet_diag_table[] is stable. */ 229 handler = rcu_dereference_protected(inet_diag_table[protocol], 1); 230 DEBUG_NET_WARN_ON_ONCE(!handler); 231 if (!handler) 232 return -ENXIO; 233 234 nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, 235 cb->nlh->nlmsg_type, sizeof(*r), nlmsg_flags); 236 if (!nlh) 237 return -EMSGSIZE; 238 239 r = nlmsg_data(nlh); 240 BUG_ON(!sk_fullsock(sk)); 241 242 inet_diag_msg_common_fill(r, sk); 243 r->idiag_state = sk->sk_state; 244 r->idiag_timer = IDIAG_TIMER_OFF; 245 r->idiag_retrans = 0; 246 r->idiag_expires = 0; 247 248 if (inet_diag_msg_attrs_fill(sk, skb, r, ext, 249 sk_user_ns(NETLINK_CB(cb->skb).sk), 250 net_admin)) 251 goto errout; 252 253 if (ext & (1 << (INET_DIAG_MEMINFO - 1))) { 254 struct inet_diag_meminfo minfo = { 255 .idiag_rmem = sk_rmem_alloc_get(sk), 256 .idiag_wmem = READ_ONCE(sk->sk_wmem_queued), 257 .idiag_fmem = READ_ONCE(sk->sk_forward_alloc), 258 .idiag_tmem = sk_wmem_alloc_get(sk), 259 }; 260 261 if (nla_put(skb, INET_DIAG_MEMINFO, sizeof(minfo), &minfo) < 0) 262 goto errout; 263 } 264 265 if (ext & (1 << (INET_DIAG_SKMEMINFO - 1))) 266 if (sock_diag_put_meminfo(sk, skb, INET_DIAG_SKMEMINFO)) 267 goto errout; 268 269 /* 270 * RAW sockets might have user-defined protocols assigned, 271 * so report the one supplied on socket creation. 272 */ 273 if (sk->sk_type == SOCK_RAW) { 274 if (nla_put_u8(skb, INET_DIAG_PROTOCOL, sk->sk_protocol)) 275 goto errout; 276 } 277 278 if (!icsk) { 279 handler->idiag_get_info(sk, r, NULL); 280 goto out; 281 } 282 283 icsk_pending = smp_load_acquire(&icsk->icsk_pending); 284 if (icsk_pending == ICSK_TIME_RETRANS || 285 icsk_pending == ICSK_TIME_REO_TIMEOUT || 286 icsk_pending == ICSK_TIME_LOSS_PROBE) { 287 r->idiag_timer = IDIAG_TIMER_ON; 288 r->idiag_retrans = READ_ONCE(icsk->icsk_retransmits); 289 r->idiag_expires = 290 jiffies_delta_to_msecs(tcp_timeout_expires(sk) - jiffies); 291 } else if (icsk_pending == ICSK_TIME_PROBE0) { 292 r->idiag_timer = IDIAG_TIMER_PROBE0; 293 r->idiag_retrans = READ_ONCE(icsk->icsk_probes_out); 294 r->idiag_expires = 295 jiffies_delta_to_msecs(tcp_timeout_expires(sk) - jiffies); 296 } else if (timer_pending(&icsk->icsk_keepalive_timer)) { 297 r->idiag_timer = IDIAG_TIMER_KEEPALIVE; 298 r->idiag_retrans = READ_ONCE(icsk->icsk_probes_out); 299 r->idiag_expires = 300 jiffies_delta_to_msecs(icsk->icsk_keepalive_timer.expires - jiffies); 301 } else if ((READ_ONCE(icsk->icsk_ack.pending) & ICSK_ACK_TIMER) && 302 timer_pending(&icsk->icsk_delack_timer)) { 303 r->idiag_timer = IDIAG_TIMER_DELACK; 304 r->idiag_expires = 305 jiffies_delta_to_msecs(icsk_delack_timeout(icsk) - jiffies); 306 } 307 308 if ((ext & (1 << (INET_DIAG_INFO - 1))) && handler->idiag_info_size) { 309 attr = nla_reserve_64bit(skb, INET_DIAG_INFO, 310 handler->idiag_info_size, 311 INET_DIAG_PAD); 312 if (!attr) 313 goto errout; 314 315 info = nla_data(attr); 316 } 317 318 if (ext & (1 << (INET_DIAG_CONG - 1))) { 319 int err = 0; 320 321 rcu_read_lock(); 322 ca_ops = READ_ONCE(icsk->icsk_ca_ops); 323 if (ca_ops) 324 err = nla_put_string(skb, INET_DIAG_CONG, ca_ops->name); 325 rcu_read_unlock(); 326 if (err < 0) 327 goto errout; 328 } 329 330 handler->idiag_get_info(sk, r, info); 331 332 if (ext & (1 << (INET_DIAG_INFO - 1)) && handler->idiag_get_aux) 333 if (handler->idiag_get_aux(sk, net_admin, skb) < 0) 334 goto errout; 335 336 if (sk->sk_state < TCP_TIME_WAIT) { 337 union tcp_cc_info info; 338 size_t sz = 0; 339 int attr; 340 341 rcu_read_lock(); 342 ca_ops = READ_ONCE(icsk->icsk_ca_ops); 343 if (ca_ops && ca_ops->get_info) 344 sz = ca_ops->get_info(sk, ext, &attr, &info); 345 rcu_read_unlock(); 346 if (sz && nla_put(skb, attr, sz, &info) < 0) 347 goto errout; 348 } 349 350 /* Keep it at the end for potential retry with a larger skb, 351 * or else do best-effort fitting, which is only done for the 352 * first_nlmsg. 353 */ 354 if (cb_data->bpf_stg_diag) { 355 bool first_nlmsg = ((unsigned char *)nlh == skb->data); 356 unsigned int prev_min_dump_alloc; 357 unsigned int total_nla_size = 0; 358 unsigned int msg_len; 359 int err; 360 361 msg_len = skb_tail_pointer(skb) - (unsigned char *)nlh; 362 err = bpf_sk_storage_diag_put(cb_data->bpf_stg_diag, sk, skb, 363 INET_DIAG_SK_BPF_STORAGES, 364 &total_nla_size); 365 366 if (!err) 367 goto out; 368 369 total_nla_size += msg_len; 370 prev_min_dump_alloc = cb->min_dump_alloc; 371 if (total_nla_size > prev_min_dump_alloc) 372 cb->min_dump_alloc = min_t(u32, total_nla_size, 373 MAX_DUMP_ALLOC_SIZE); 374 375 if (!first_nlmsg) 376 goto errout; 377 378 if (cb->min_dump_alloc > prev_min_dump_alloc) 379 /* Retry with pskb_expand_head() with 380 * __GFP_DIRECT_RECLAIM 381 */ 382 goto errout; 383 384 WARN_ON_ONCE(total_nla_size <= prev_min_dump_alloc); 385 386 /* Send what we have for this sk 387 * and move on to the next sk in the following 388 * dump() 389 */ 390 } 391 392 out: 393 nlmsg_end(skb, nlh); 394 return 0; 395 396 errout: 397 nlmsg_cancel(skb, nlh); 398 return -EMSGSIZE; 399 } 400 EXPORT_SYMBOL_GPL(inet_sk_diag_fill); 401 402 static int inet_diag_cmd_exact(int cmd, struct sk_buff *in_skb, 403 const struct nlmsghdr *nlh, 404 int hdrlen, 405 const struct inet_diag_req_v2 *req) 406 { 407 const struct inet_diag_handler *handler; 408 struct inet_diag_dump_data dump_data; 409 int err, protocol; 410 411 memset(&dump_data, 0, sizeof(dump_data)); 412 err = inet_diag_parse_attrs(nlh, hdrlen, dump_data.req_nlas); 413 if (err) 414 return err; 415 416 protocol = inet_diag_get_protocol(req, &dump_data); 417 418 handler = inet_diag_lock_handler(protocol); 419 if (!handler) 420 return -ENOENT; 421 422 if (cmd == SOCK_DIAG_BY_FAMILY) { 423 struct netlink_callback cb = { 424 .nlh = nlh, 425 .skb = in_skb, 426 .data = &dump_data, 427 }; 428 err = handler->dump_one(&cb, req); 429 } else if (cmd == SOCK_DESTROY && handler->destroy) { 430 err = handler->destroy(in_skb, req); 431 } else { 432 err = -EOPNOTSUPP; 433 } 434 inet_diag_unlock_handler(handler); 435 436 return err; 437 } 438 439 static int bitstring_match(const __be32 *a1, const __be32 *a2, int bits) 440 { 441 int words = bits >> 5; 442 443 bits &= 0x1f; 444 445 if (words) { 446 if (memcmp(a1, a2, words << 2)) 447 return 0; 448 } 449 if (bits) { 450 __be32 w1, w2; 451 __be32 mask; 452 453 w1 = a1[words]; 454 w2 = a2[words]; 455 456 mask = htonl((0xffffffff) << (32 - bits)); 457 458 if ((w1 ^ w2) & mask) 459 return 0; 460 } 461 462 return 1; 463 } 464 465 static int inet_diag_bc_run(const struct nlattr *_bc, 466 const struct inet_diag_entry *entry) 467 { 468 const void *bc = nla_data(_bc); 469 int len = nla_len(_bc); 470 471 while (len > 0) { 472 int yes = 1; 473 const struct inet_diag_bc_op *op = bc; 474 475 switch (op->code) { 476 case INET_DIAG_BC_NOP: 477 break; 478 case INET_DIAG_BC_JMP: 479 yes = 0; 480 break; 481 case INET_DIAG_BC_S_EQ: 482 yes = entry->sport == op[1].no; 483 break; 484 case INET_DIAG_BC_S_GE: 485 yes = entry->sport >= op[1].no; 486 break; 487 case INET_DIAG_BC_S_LE: 488 yes = entry->sport <= op[1].no; 489 break; 490 case INET_DIAG_BC_D_EQ: 491 yes = entry->dport == op[1].no; 492 break; 493 case INET_DIAG_BC_D_GE: 494 yes = entry->dport >= op[1].no; 495 break; 496 case INET_DIAG_BC_D_LE: 497 yes = entry->dport <= op[1].no; 498 break; 499 case INET_DIAG_BC_AUTO: 500 yes = !(entry->userlocks & SOCK_BINDPORT_LOCK); 501 break; 502 case INET_DIAG_BC_S_COND: 503 case INET_DIAG_BC_D_COND: { 504 const struct inet_diag_hostcond *cond; 505 const __be32 *addr; 506 507 cond = (const struct inet_diag_hostcond *)(op + 1); 508 if (cond->port != -1 && 509 cond->port != (op->code == INET_DIAG_BC_S_COND ? 510 entry->sport : entry->dport)) { 511 yes = 0; 512 break; 513 } 514 515 if (op->code == INET_DIAG_BC_S_COND) 516 addr = entry->saddr; 517 else 518 addr = entry->daddr; 519 520 if (cond->family != AF_UNSPEC && 521 cond->family != entry->family) { 522 if (entry->family == AF_INET6 && 523 cond->family == AF_INET) { 524 if (addr[0] == 0 && addr[1] == 0 && 525 addr[2] == htonl(0xffff) && 526 bitstring_match(addr + 3, 527 cond->addr, 528 cond->prefix_len)) 529 break; 530 } 531 yes = 0; 532 break; 533 } 534 535 if (cond->prefix_len == 0) 536 break; 537 if (bitstring_match(addr, cond->addr, 538 cond->prefix_len)) 539 break; 540 yes = 0; 541 break; 542 } 543 case INET_DIAG_BC_DEV_COND: { 544 u32 ifindex; 545 546 ifindex = *((const u32 *)(op + 1)); 547 if (ifindex != entry->ifindex) 548 yes = 0; 549 break; 550 } 551 case INET_DIAG_BC_MARK_COND: { 552 struct inet_diag_markcond *cond; 553 554 cond = (struct inet_diag_markcond *)(op + 1); 555 if ((entry->mark & cond->mask) != cond->mark) 556 yes = 0; 557 break; 558 } 559 #ifdef CONFIG_SOCK_CGROUP_DATA 560 case INET_DIAG_BC_CGROUP_COND: { 561 u64 cgroup_id; 562 563 cgroup_id = get_unaligned((const u64 *)(op + 1)); 564 if (cgroup_id != entry->cgroup_id) 565 yes = 0; 566 break; 567 } 568 #endif 569 } 570 571 if (yes) { 572 len -= op->yes; 573 bc += op->yes; 574 } else { 575 len -= op->no; 576 bc += op->no; 577 } 578 } 579 return len == 0; 580 } 581 582 /* This helper is available for all sockets (ESTABLISH, TIMEWAIT, SYN_RECV) 583 */ 584 static void entry_fill_addrs(struct inet_diag_entry *entry, 585 const struct sock *sk) 586 { 587 #if IS_ENABLED(CONFIG_IPV6) 588 if (entry->family == AF_INET6) { 589 entry->saddr = sk->sk_v6_rcv_saddr.s6_addr32; 590 entry->daddr = sk->sk_v6_daddr.s6_addr32; 591 } else 592 #endif 593 { 594 entry->saddr = &sk->sk_rcv_saddr; 595 entry->daddr = &sk->sk_daddr; 596 } 597 } 598 599 int inet_diag_bc_sk(const struct inet_diag_dump_data *cb_data, struct sock *sk) 600 { 601 const struct nlattr *bc = cb_data->inet_diag_nla_bc; 602 const struct inet_sock *inet = inet_sk(sk); 603 struct inet_diag_entry entry; 604 605 if (!bc) 606 return 1; 607 608 entry.family = READ_ONCE(sk->sk_family); 609 entry_fill_addrs(&entry, sk); 610 entry.sport = READ_ONCE(inet->inet_num); 611 entry.dport = ntohs(READ_ONCE(inet->inet_dport)); 612 entry.ifindex = READ_ONCE(sk->sk_bound_dev_if); 613 if (cb_data->userlocks_needed) 614 entry.userlocks = sk_fullsock(sk) ? READ_ONCE(sk->sk_userlocks) : 0; 615 if (cb_data->mark_needed) { 616 if (sk_fullsock(sk)) 617 entry.mark = READ_ONCE(sk->sk_mark); 618 else if (sk->sk_state == TCP_NEW_SYN_RECV) 619 entry.mark = inet_rsk(inet_reqsk(sk))->ir_mark; 620 else if (sk->sk_state == TCP_TIME_WAIT) 621 entry.mark = inet_twsk(sk)->tw_mark; 622 else 623 entry.mark = 0; 624 } 625 #ifdef CONFIG_SOCK_CGROUP_DATA 626 if (cb_data->cgroup_needed) 627 entry.cgroup_id = sk_fullsock(sk) ? 628 cgroup_id(sock_cgroup_ptr(&sk->sk_cgrp_data)) : 0; 629 #endif 630 631 return inet_diag_bc_run(bc, &entry); 632 } 633 EXPORT_SYMBOL_GPL(inet_diag_bc_sk); 634 635 static int valid_cc(const void *bc, int len, int cc) 636 { 637 while (len >= 0) { 638 const struct inet_diag_bc_op *op = bc; 639 640 if (cc > len) 641 return 0; 642 if (cc == len) 643 return 1; 644 if (op->yes < 4 || op->yes & 3) 645 return 0; 646 len -= op->yes; 647 bc += op->yes; 648 } 649 return 0; 650 } 651 652 /* data is u32 ifindex */ 653 static bool valid_devcond(const struct inet_diag_bc_op *op, int len, 654 int *min_len) 655 { 656 /* Check ifindex space. */ 657 *min_len += sizeof(u32); 658 if (len < *min_len) 659 return false; 660 661 return true; 662 } 663 /* Validate an inet_diag_hostcond. */ 664 static bool valid_hostcond(const struct inet_diag_bc_op *op, int len, 665 int *min_len) 666 { 667 struct inet_diag_hostcond *cond; 668 int addr_len; 669 670 /* Check hostcond space. */ 671 *min_len += sizeof(struct inet_diag_hostcond); 672 if (len < *min_len) 673 return false; 674 cond = (struct inet_diag_hostcond *)(op + 1); 675 676 /* Check address family and address length. */ 677 switch (cond->family) { 678 case AF_UNSPEC: 679 addr_len = 0; 680 break; 681 case AF_INET: 682 addr_len = sizeof(struct in_addr); 683 break; 684 case AF_INET6: 685 addr_len = sizeof(struct in6_addr); 686 break; 687 default: 688 return false; 689 } 690 *min_len += addr_len; 691 if (len < *min_len) 692 return false; 693 694 /* Check prefix length (in bits) vs address length (in bytes). */ 695 if (cond->prefix_len > 8 * addr_len) 696 return false; 697 698 return true; 699 } 700 701 /* Validate a port comparison operator. */ 702 static bool valid_port_comparison(const struct inet_diag_bc_op *op, 703 int len, int *min_len) 704 { 705 /* Port comparisons put the port in a follow-on inet_diag_bc_op. */ 706 *min_len += sizeof(struct inet_diag_bc_op); 707 if (len < *min_len) 708 return false; 709 return true; 710 } 711 712 static bool valid_markcond(const struct inet_diag_bc_op *op, int len, 713 int *min_len) 714 { 715 *min_len += sizeof(struct inet_diag_markcond); 716 return len >= *min_len; 717 } 718 719 #ifdef CONFIG_SOCK_CGROUP_DATA 720 static bool valid_cgroupcond(const struct inet_diag_bc_op *op, int len, 721 int *min_len) 722 { 723 *min_len += sizeof(u64); 724 return len >= *min_len; 725 } 726 #endif 727 728 static int inet_diag_bc_audit(struct inet_diag_dump_data *cb_data, 729 const struct sk_buff *skb) 730 { 731 const struct nlattr *attr = cb_data->inet_diag_nla_bc; 732 const void *bytecode, *bc; 733 int bytecode_len, len; 734 bool net_admin; 735 736 if (!attr) 737 return 0; 738 739 if (nla_len(attr) < sizeof(struct inet_diag_bc_op)) 740 return -EINVAL; 741 742 net_admin = netlink_net_capable(skb, CAP_NET_ADMIN); 743 bytecode = bc = nla_data(attr); 744 len = bytecode_len = nla_len(attr); 745 746 while (len > 0) { 747 int min_len = sizeof(struct inet_diag_bc_op); 748 const struct inet_diag_bc_op *op = bc; 749 750 switch (op->code) { 751 case INET_DIAG_BC_S_COND: 752 case INET_DIAG_BC_D_COND: 753 if (!valid_hostcond(bc, len, &min_len)) 754 return -EINVAL; 755 break; 756 case INET_DIAG_BC_DEV_COND: 757 if (!valid_devcond(bc, len, &min_len)) 758 return -EINVAL; 759 break; 760 case INET_DIAG_BC_S_EQ: 761 case INET_DIAG_BC_S_GE: 762 case INET_DIAG_BC_S_LE: 763 case INET_DIAG_BC_D_EQ: 764 case INET_DIAG_BC_D_GE: 765 case INET_DIAG_BC_D_LE: 766 if (!valid_port_comparison(bc, len, &min_len)) 767 return -EINVAL; 768 break; 769 case INET_DIAG_BC_MARK_COND: 770 if (!net_admin) 771 return -EPERM; 772 if (!valid_markcond(bc, len, &min_len)) 773 return -EINVAL; 774 cb_data->mark_needed = true; 775 break; 776 #ifdef CONFIG_SOCK_CGROUP_DATA 777 case INET_DIAG_BC_CGROUP_COND: 778 if (!valid_cgroupcond(bc, len, &min_len)) 779 return -EINVAL; 780 cb_data->cgroup_needed = true; 781 break; 782 #endif 783 case INET_DIAG_BC_AUTO: 784 cb_data->userlocks_needed = true; 785 fallthrough; 786 case INET_DIAG_BC_JMP: 787 case INET_DIAG_BC_NOP: 788 break; 789 default: 790 return -EINVAL; 791 } 792 793 if (op->code != INET_DIAG_BC_NOP) { 794 if (op->no < min_len || op->no > len + 4 || op->no & 3) 795 return -EINVAL; 796 if (op->no < len && 797 !valid_cc(bytecode, bytecode_len, len - op->no)) 798 return -EINVAL; 799 } 800 801 if (op->yes < min_len || op->yes > len + 4 || op->yes & 3) 802 return -EINVAL; 803 bc += op->yes; 804 len -= op->yes; 805 } 806 return len == 0 ? 0 : -EINVAL; 807 } 808 809 static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 810 const struct inet_diag_req_v2 *r) 811 { 812 struct inet_diag_dump_data *cb_data = cb->data; 813 const struct inet_diag_handler *handler; 814 u32 prev_min_dump_alloc; 815 int protocol, err = 0; 816 817 protocol = inet_diag_get_protocol(r, cb_data); 818 819 again: 820 prev_min_dump_alloc = cb->min_dump_alloc; 821 handler = inet_diag_lock_handler(protocol); 822 if (handler) { 823 handler->dump(skb, cb, r); 824 inet_diag_unlock_handler(handler); 825 } else { 826 err = -ENOENT; 827 } 828 /* The skb is not large enough to fit one sk info and 829 * inet_sk_diag_fill() has requested for a larger skb. 830 */ 831 if (!skb->len && cb->min_dump_alloc > prev_min_dump_alloc) { 832 err = pskb_expand_head(skb, 0, cb->min_dump_alloc, GFP_KERNEL); 833 if (!err) 834 goto again; 835 } 836 837 return err ? : skb->len; 838 } 839 840 static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) 841 { 842 return __inet_diag_dump(skb, cb, nlmsg_data(cb->nlh)); 843 } 844 845 static int __inet_diag_dump_start(struct netlink_callback *cb, int hdrlen) 846 { 847 const struct nlmsghdr *nlh = cb->nlh; 848 struct inet_diag_dump_data *cb_data; 849 struct sk_buff *skb = cb->skb; 850 struct nlattr *nla; 851 int err; 852 853 cb_data = kzalloc_obj(*cb_data); 854 if (!cb_data) 855 return -ENOMEM; 856 857 err = inet_diag_parse_attrs(nlh, hdrlen, cb_data->req_nlas); 858 if (err) { 859 kfree(cb_data); 860 return err; 861 } 862 err = inet_diag_bc_audit(cb_data, skb); 863 if (err) { 864 kfree(cb_data); 865 return err; 866 } 867 868 nla = cb_data->inet_diag_nla_bpf_stgs; 869 if (nla) { 870 struct bpf_sk_storage_diag *bpf_stg_diag; 871 872 bpf_stg_diag = bpf_sk_storage_diag_alloc(nla); 873 if (IS_ERR(bpf_stg_diag)) { 874 kfree(cb_data); 875 return PTR_ERR(bpf_stg_diag); 876 } 877 cb_data->bpf_stg_diag = bpf_stg_diag; 878 } 879 880 cb->data = cb_data; 881 return 0; 882 } 883 884 static int inet_diag_dump_start(struct netlink_callback *cb) 885 { 886 return __inet_diag_dump_start(cb, sizeof(struct inet_diag_req_v2)); 887 } 888 889 static int inet_diag_dump_start_compat(struct netlink_callback *cb) 890 { 891 return __inet_diag_dump_start(cb, sizeof(struct inet_diag_req)); 892 } 893 894 static int inet_diag_dump_done(struct netlink_callback *cb) 895 { 896 struct inet_diag_dump_data *cb_data = cb->data; 897 898 bpf_sk_storage_diag_free(cb_data->bpf_stg_diag); 899 kfree(cb->data); 900 901 return 0; 902 } 903 904 static int inet_diag_type2proto(int type) 905 { 906 switch (type) { 907 case TCPDIAG_GETSOCK: 908 return IPPROTO_TCP; 909 default: 910 return 0; 911 } 912 } 913 914 static int inet_diag_dump_compat(struct sk_buff *skb, 915 struct netlink_callback *cb) 916 { 917 struct inet_diag_req *rc = nlmsg_data(cb->nlh); 918 struct inet_diag_req_v2 req; 919 920 req.sdiag_family = AF_UNSPEC; /* compatibility */ 921 req.sdiag_protocol = inet_diag_type2proto(cb->nlh->nlmsg_type); 922 req.idiag_ext = rc->idiag_ext; 923 req.pad = 0; 924 req.idiag_states = rc->idiag_states; 925 req.id = rc->id; 926 927 return __inet_diag_dump(skb, cb, &req); 928 } 929 930 static int inet_diag_get_exact_compat(struct sk_buff *in_skb, 931 const struct nlmsghdr *nlh) 932 { 933 struct inet_diag_req *rc = nlmsg_data(nlh); 934 struct inet_diag_req_v2 req; 935 936 req.sdiag_family = rc->idiag_family; 937 req.sdiag_protocol = inet_diag_type2proto(nlh->nlmsg_type); 938 req.idiag_ext = rc->idiag_ext; 939 req.pad = 0; 940 req.idiag_states = rc->idiag_states; 941 req.id = rc->id; 942 943 return inet_diag_cmd_exact(SOCK_DIAG_BY_FAMILY, in_skb, nlh, 944 sizeof(struct inet_diag_req), &req); 945 } 946 947 static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh) 948 { 949 int hdrlen = sizeof(struct inet_diag_req); 950 struct net *net = sock_net(skb->sk); 951 952 if (nlh->nlmsg_type >= INET_DIAG_GETSOCK_MAX || 953 nlmsg_len(nlh) < hdrlen) 954 return -EINVAL; 955 956 if (nlh->nlmsg_flags & NLM_F_DUMP) { 957 struct netlink_dump_control c = { 958 .start = inet_diag_dump_start_compat, 959 .done = inet_diag_dump_done, 960 .dump = inet_diag_dump_compat, 961 }; 962 return netlink_dump_start(net->diag_nlsk, skb, nlh, &c); 963 } 964 965 return inet_diag_get_exact_compat(skb, nlh); 966 } 967 968 static int inet_diag_handler_cmd(struct sk_buff *skb, struct nlmsghdr *h) 969 { 970 int hdrlen = sizeof(struct inet_diag_req_v2); 971 struct net *net = sock_net(skb->sk); 972 973 if (nlmsg_len(h) < hdrlen) 974 return -EINVAL; 975 976 if (h->nlmsg_type == SOCK_DIAG_BY_FAMILY && 977 h->nlmsg_flags & NLM_F_DUMP) { 978 struct netlink_dump_control c = { 979 .start = inet_diag_dump_start, 980 .done = inet_diag_dump_done, 981 .dump = inet_diag_dump, 982 }; 983 return netlink_dump_start(net->diag_nlsk, skb, h, &c); 984 } 985 986 return inet_diag_cmd_exact(h->nlmsg_type, skb, h, hdrlen, 987 nlmsg_data(h)); 988 } 989 990 static 991 int inet_diag_handler_get_info(struct sk_buff *skb, struct sock *sk) 992 { 993 const struct inet_diag_handler *handler; 994 struct nlmsghdr *nlh; 995 struct nlattr *attr; 996 struct inet_diag_msg *r; 997 void *info = NULL; 998 int err = 0; 999 1000 nlh = nlmsg_put(skb, 0, 0, SOCK_DIAG_BY_FAMILY, sizeof(*r), 0); 1001 if (!nlh) 1002 return -ENOMEM; 1003 1004 r = nlmsg_data(nlh); 1005 memset(r, 0, sizeof(*r)); 1006 inet_diag_msg_common_fill(r, sk); 1007 if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_STREAM) 1008 r->id.idiag_sport = inet_sk(sk)->inet_sport; 1009 r->idiag_state = sk->sk_state; 1010 1011 if ((err = nla_put_u8(skb, INET_DIAG_PROTOCOL, sk->sk_protocol))) { 1012 nlmsg_cancel(skb, nlh); 1013 return err; 1014 } 1015 1016 handler = inet_diag_lock_handler(sk->sk_protocol); 1017 if (!handler) { 1018 nlmsg_cancel(skb, nlh); 1019 return -ENOENT; 1020 } 1021 1022 attr = handler->idiag_info_size 1023 ? nla_reserve_64bit(skb, INET_DIAG_INFO, 1024 handler->idiag_info_size, 1025 INET_DIAG_PAD) 1026 : NULL; 1027 if (attr) 1028 info = nla_data(attr); 1029 1030 handler->idiag_get_info(sk, r, info); 1031 inet_diag_unlock_handler(handler); 1032 1033 nlmsg_end(skb, nlh); 1034 return 0; 1035 } 1036 1037 static const struct sock_diag_handler inet_diag_handler = { 1038 .owner = THIS_MODULE, 1039 .family = AF_INET, 1040 .dump = inet_diag_handler_cmd, 1041 .get_info = inet_diag_handler_get_info, 1042 .destroy = inet_diag_handler_cmd, 1043 }; 1044 1045 static const struct sock_diag_handler inet6_diag_handler = { 1046 .owner = THIS_MODULE, 1047 .family = AF_INET6, 1048 .dump = inet_diag_handler_cmd, 1049 .get_info = inet_diag_handler_get_info, 1050 .destroy = inet_diag_handler_cmd, 1051 }; 1052 1053 int inet_diag_register(const struct inet_diag_handler *h) 1054 { 1055 const __u16 type = h->idiag_type; 1056 1057 if (type >= IPPROTO_MAX) 1058 return -EINVAL; 1059 1060 return !cmpxchg((const struct inet_diag_handler **)&inet_diag_table[type], 1061 NULL, h) ? 0 : -EEXIST; 1062 } 1063 EXPORT_SYMBOL_GPL(inet_diag_register); 1064 1065 void inet_diag_unregister(const struct inet_diag_handler *h) 1066 { 1067 const __u16 type = h->idiag_type; 1068 1069 if (type >= IPPROTO_MAX) 1070 return; 1071 1072 xchg((const struct inet_diag_handler **)&inet_diag_table[type], 1073 NULL); 1074 } 1075 EXPORT_SYMBOL_GPL(inet_diag_unregister); 1076 1077 static const struct sock_diag_inet_compat inet_diag_compat = { 1078 .owner = THIS_MODULE, 1079 .fn = inet_diag_rcv_msg_compat, 1080 }; 1081 1082 static int __init inet_diag_init(void) 1083 { 1084 const int inet_diag_table_size = (IPPROTO_MAX * 1085 sizeof(struct inet_diag_handler *)); 1086 int err = -ENOMEM; 1087 1088 inet_diag_table = kzalloc(inet_diag_table_size, GFP_KERNEL); 1089 if (!inet_diag_table) 1090 goto out; 1091 1092 err = sock_diag_register(&inet_diag_handler); 1093 if (err) 1094 goto out_free_nl; 1095 1096 err = sock_diag_register(&inet6_diag_handler); 1097 if (err) 1098 goto out_free_inet; 1099 1100 sock_diag_register_inet_compat(&inet_diag_compat); 1101 out: 1102 return err; 1103 1104 out_free_inet: 1105 sock_diag_unregister(&inet_diag_handler); 1106 out_free_nl: 1107 kfree(inet_diag_table); 1108 goto out; 1109 } 1110 1111 static void __exit inet_diag_exit(void) 1112 { 1113 sock_diag_unregister(&inet6_diag_handler); 1114 sock_diag_unregister(&inet_diag_handler); 1115 sock_diag_unregister_inet_compat(&inet_diag_compat); 1116 kfree(inet_diag_table); 1117 } 1118 1119 module_init(inet_diag_init); 1120 module_exit(inet_diag_exit); 1121 MODULE_LICENSE("GPL"); 1122 MODULE_DESCRIPTION("INET/INET6: socket monitoring via SOCK_DIAG"); 1123 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2 /* AF_INET */); 1124 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10 /* AF_INET6 */); 1125