1 /* 2 * net/dccp/proto.c 3 * 4 * An implementation of the DCCP protocol 5 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 */ 11 12 #include <linux/dccp.h> 13 #include <linux/module.h> 14 #include <linux/types.h> 15 #include <linux/sched.h> 16 #include <linux/kernel.h> 17 #include <linux/skbuff.h> 18 #include <linux/netdevice.h> 19 #include <linux/in.h> 20 #include <linux/if_arp.h> 21 #include <linux/init.h> 22 #include <linux/random.h> 23 #include <linux/slab.h> 24 #include <net/checksum.h> 25 26 #include <net/inet_sock.h> 27 #include <net/inet_common.h> 28 #include <net/sock.h> 29 #include <net/xfrm.h> 30 31 #include <asm/ioctls.h> 32 #include <linux/spinlock.h> 33 #include <linux/timer.h> 34 #include <linux/delay.h> 35 #include <linux/poll.h> 36 37 #include "ccid.h" 38 #include "dccp.h" 39 #include "feat.h" 40 41 #define CREATE_TRACE_POINTS 42 #include "trace.h" 43 44 DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly; 45 46 EXPORT_SYMBOL_GPL(dccp_statistics); 47 48 struct percpu_counter dccp_orphan_count; 49 EXPORT_SYMBOL_GPL(dccp_orphan_count); 50 51 struct inet_hashinfo dccp_hashinfo; 52 EXPORT_SYMBOL_GPL(dccp_hashinfo); 53 54 /* the maximum queue length for tx in packets. 0 is no limit */ 55 int sysctl_dccp_tx_qlen __read_mostly = 5; 56 57 #ifdef CONFIG_IP_DCCP_DEBUG 58 static const char *dccp_state_name(const int state) 59 { 60 static const char *const dccp_state_names[] = { 61 [DCCP_OPEN] = "OPEN", 62 [DCCP_REQUESTING] = "REQUESTING", 63 [DCCP_PARTOPEN] = "PARTOPEN", 64 [DCCP_LISTEN] = "LISTEN", 65 [DCCP_RESPOND] = "RESPOND", 66 [DCCP_CLOSING] = "CLOSING", 67 [DCCP_ACTIVE_CLOSEREQ] = "CLOSEREQ", 68 [DCCP_PASSIVE_CLOSE] = "PASSIVE_CLOSE", 69 [DCCP_PASSIVE_CLOSEREQ] = "PASSIVE_CLOSEREQ", 70 [DCCP_TIME_WAIT] = "TIME_WAIT", 71 [DCCP_CLOSED] = "CLOSED", 72 }; 73 74 if (state >= DCCP_MAX_STATES) 75 return "INVALID STATE!"; 76 else 77 return dccp_state_names[state]; 78 } 79 #endif 80 81 void dccp_set_state(struct sock *sk, const int state) 82 { 83 const int oldstate = sk->sk_state; 84 85 dccp_pr_debug("%s(%p) %s --> %s\n", dccp_role(sk), sk, 86 dccp_state_name(oldstate), dccp_state_name(state)); 87 WARN_ON(state == oldstate); 88 89 switch (state) { 90 case DCCP_OPEN: 91 if (oldstate != DCCP_OPEN) 92 DCCP_INC_STATS(DCCP_MIB_CURRESTAB); 93 /* Client retransmits all Confirm options until entering OPEN */ 94 if (oldstate == DCCP_PARTOPEN) 95 dccp_feat_list_purge(&dccp_sk(sk)->dccps_featneg); 96 break; 97 98 case DCCP_CLOSED: 99 if (oldstate == DCCP_OPEN || oldstate == DCCP_ACTIVE_CLOSEREQ || 100 oldstate == DCCP_CLOSING) 101 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS); 102 103 sk->sk_prot->unhash(sk); 104 if (inet_csk(sk)->icsk_bind_hash != NULL && 105 !(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) 106 inet_put_port(sk); 107 /* fall through */ 108 default: 109 if (oldstate == DCCP_OPEN) 110 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB); 111 } 112 113 /* Change state AFTER socket is unhashed to avoid closed 114 * socket sitting in hash tables. 115 */ 116 inet_sk_set_state(sk, state); 117 } 118 119 EXPORT_SYMBOL_GPL(dccp_set_state); 120 121 static void dccp_finish_passive_close(struct sock *sk) 122 { 123 switch (sk->sk_state) { 124 case DCCP_PASSIVE_CLOSE: 125 /* Node (client or server) has received Close packet. */ 126 dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED); 127 dccp_set_state(sk, DCCP_CLOSED); 128 break; 129 case DCCP_PASSIVE_CLOSEREQ: 130 /* 131 * Client received CloseReq. We set the `active' flag so that 132 * dccp_send_close() retransmits the Close as per RFC 4340, 8.3. 133 */ 134 dccp_send_close(sk, 1); 135 dccp_set_state(sk, DCCP_CLOSING); 136 } 137 } 138 139 void dccp_done(struct sock *sk) 140 { 141 dccp_set_state(sk, DCCP_CLOSED); 142 dccp_clear_xmit_timers(sk); 143 144 sk->sk_shutdown = SHUTDOWN_MASK; 145 146 if (!sock_flag(sk, SOCK_DEAD)) 147 sk->sk_state_change(sk); 148 else 149 inet_csk_destroy_sock(sk); 150 } 151 152 EXPORT_SYMBOL_GPL(dccp_done); 153 154 const char *dccp_packet_name(const int type) 155 { 156 static const char *const dccp_packet_names[] = { 157 [DCCP_PKT_REQUEST] = "REQUEST", 158 [DCCP_PKT_RESPONSE] = "RESPONSE", 159 [DCCP_PKT_DATA] = "DATA", 160 [DCCP_PKT_ACK] = "ACK", 161 [DCCP_PKT_DATAACK] = "DATAACK", 162 [DCCP_PKT_CLOSEREQ] = "CLOSEREQ", 163 [DCCP_PKT_CLOSE] = "CLOSE", 164 [DCCP_PKT_RESET] = "RESET", 165 [DCCP_PKT_SYNC] = "SYNC", 166 [DCCP_PKT_SYNCACK] = "SYNCACK", 167 }; 168 169 if (type >= DCCP_NR_PKT_TYPES) 170 return "INVALID"; 171 else 172 return dccp_packet_names[type]; 173 } 174 175 EXPORT_SYMBOL_GPL(dccp_packet_name); 176 177 static void dccp_sk_destruct(struct sock *sk) 178 { 179 struct dccp_sock *dp = dccp_sk(sk); 180 181 ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk); 182 dp->dccps_hc_tx_ccid = NULL; 183 inet_sock_destruct(sk); 184 } 185 186 int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized) 187 { 188 struct dccp_sock *dp = dccp_sk(sk); 189 struct inet_connection_sock *icsk = inet_csk(sk); 190 191 icsk->icsk_rto = DCCP_TIMEOUT_INIT; 192 icsk->icsk_syn_retries = sysctl_dccp_request_retries; 193 sk->sk_state = DCCP_CLOSED; 194 sk->sk_write_space = dccp_write_space; 195 sk->sk_destruct = dccp_sk_destruct; 196 icsk->icsk_sync_mss = dccp_sync_mss; 197 dp->dccps_mss_cache = 536; 198 dp->dccps_rate_last = jiffies; 199 dp->dccps_role = DCCP_ROLE_UNDEFINED; 200 dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT; 201 dp->dccps_tx_qlen = sysctl_dccp_tx_qlen; 202 203 dccp_init_xmit_timers(sk); 204 205 INIT_LIST_HEAD(&dp->dccps_featneg); 206 /* control socket doesn't need feat nego */ 207 if (likely(ctl_sock_initialized)) 208 return dccp_feat_init(sk); 209 return 0; 210 } 211 212 EXPORT_SYMBOL_GPL(dccp_init_sock); 213 214 void dccp_destroy_sock(struct sock *sk) 215 { 216 struct dccp_sock *dp = dccp_sk(sk); 217 218 __skb_queue_purge(&sk->sk_write_queue); 219 if (sk->sk_send_head != NULL) { 220 kfree_skb(sk->sk_send_head); 221 sk->sk_send_head = NULL; 222 } 223 224 /* Clean up a referenced DCCP bind bucket. */ 225 if (inet_csk(sk)->icsk_bind_hash != NULL) 226 inet_put_port(sk); 227 228 kfree(dp->dccps_service_list); 229 dp->dccps_service_list = NULL; 230 231 if (dp->dccps_hc_rx_ackvec != NULL) { 232 dccp_ackvec_free(dp->dccps_hc_rx_ackvec); 233 dp->dccps_hc_rx_ackvec = NULL; 234 } 235 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk); 236 dp->dccps_hc_rx_ccid = NULL; 237 238 /* clean up feature negotiation state */ 239 dccp_feat_list_purge(&dp->dccps_featneg); 240 } 241 242 EXPORT_SYMBOL_GPL(dccp_destroy_sock); 243 244 static inline int dccp_listen_start(struct sock *sk, int backlog) 245 { 246 struct dccp_sock *dp = dccp_sk(sk); 247 248 dp->dccps_role = DCCP_ROLE_LISTEN; 249 /* do not start to listen if feature negotiation setup fails */ 250 if (dccp_feat_finalise_settings(dp)) 251 return -EPROTO; 252 return inet_csk_listen_start(sk, backlog); 253 } 254 255 static inline int dccp_need_reset(int state) 256 { 257 return state != DCCP_CLOSED && state != DCCP_LISTEN && 258 state != DCCP_REQUESTING; 259 } 260 261 int dccp_disconnect(struct sock *sk, int flags) 262 { 263 struct inet_connection_sock *icsk = inet_csk(sk); 264 struct inet_sock *inet = inet_sk(sk); 265 struct dccp_sock *dp = dccp_sk(sk); 266 const int old_state = sk->sk_state; 267 268 if (old_state != DCCP_CLOSED) 269 dccp_set_state(sk, DCCP_CLOSED); 270 271 /* 272 * This corresponds to the ABORT function of RFC793, sec. 3.8 273 * TCP uses a RST segment, DCCP a Reset packet with Code 2, "Aborted". 274 */ 275 if (old_state == DCCP_LISTEN) { 276 inet_csk_listen_stop(sk); 277 } else if (dccp_need_reset(old_state)) { 278 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED); 279 sk->sk_err = ECONNRESET; 280 } else if (old_state == DCCP_REQUESTING) 281 sk->sk_err = ECONNRESET; 282 283 dccp_clear_xmit_timers(sk); 284 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk); 285 dp->dccps_hc_rx_ccid = NULL; 286 287 __skb_queue_purge(&sk->sk_receive_queue); 288 __skb_queue_purge(&sk->sk_write_queue); 289 if (sk->sk_send_head != NULL) { 290 __kfree_skb(sk->sk_send_head); 291 sk->sk_send_head = NULL; 292 } 293 294 inet->inet_dport = 0; 295 296 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK)) 297 inet_reset_saddr(sk); 298 299 sk->sk_shutdown = 0; 300 sock_reset_flag(sk, SOCK_DONE); 301 302 icsk->icsk_backoff = 0; 303 inet_csk_delack_init(sk); 304 __sk_dst_reset(sk); 305 306 WARN_ON(inet->inet_num && !icsk->icsk_bind_hash); 307 308 sk->sk_error_report(sk); 309 return 0; 310 } 311 312 EXPORT_SYMBOL_GPL(dccp_disconnect); 313 314 /* 315 * Wait for a DCCP event. 316 * 317 * Note that we don't need to lock the socket, as the upper poll layers 318 * take care of normal races (between the test and the event) and we don't 319 * go look at any of the socket buffers directly. 320 */ 321 __poll_t dccp_poll(struct file *file, struct socket *sock, 322 poll_table *wait) 323 { 324 __poll_t mask; 325 struct sock *sk = sock->sk; 326 327 sock_poll_wait(file, sock, wait); 328 if (sk->sk_state == DCCP_LISTEN) 329 return inet_csk_listen_poll(sk); 330 331 /* Socket is not locked. We are protected from async events 332 by poll logic and correct handling of state changes 333 made by another threads is impossible in any case. 334 */ 335 336 mask = 0; 337 if (sk->sk_err) 338 mask = EPOLLERR; 339 340 if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == DCCP_CLOSED) 341 mask |= EPOLLHUP; 342 if (sk->sk_shutdown & RCV_SHUTDOWN) 343 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP; 344 345 /* Connected? */ 346 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) { 347 if (atomic_read(&sk->sk_rmem_alloc) > 0) 348 mask |= EPOLLIN | EPOLLRDNORM; 349 350 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 351 if (sk_stream_is_writeable(sk)) { 352 mask |= EPOLLOUT | EPOLLWRNORM; 353 } else { /* send SIGIO later */ 354 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); 355 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 356 357 /* Race breaker. If space is freed after 358 * wspace test but before the flags are set, 359 * IO signal will be lost. 360 */ 361 if (sk_stream_is_writeable(sk)) 362 mask |= EPOLLOUT | EPOLLWRNORM; 363 } 364 } 365 } 366 return mask; 367 } 368 369 EXPORT_SYMBOL_GPL(dccp_poll); 370 371 int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg) 372 { 373 int rc = -ENOTCONN; 374 375 lock_sock(sk); 376 377 if (sk->sk_state == DCCP_LISTEN) 378 goto out; 379 380 switch (cmd) { 381 case SIOCINQ: { 382 struct sk_buff *skb; 383 unsigned long amount = 0; 384 385 skb = skb_peek(&sk->sk_receive_queue); 386 if (skb != NULL) { 387 /* 388 * We will only return the amount of this packet since 389 * that is all that will be read. 390 */ 391 amount = skb->len; 392 } 393 rc = put_user(amount, (int __user *)arg); 394 } 395 break; 396 default: 397 rc = -ENOIOCTLCMD; 398 break; 399 } 400 out: 401 release_sock(sk); 402 return rc; 403 } 404 405 EXPORT_SYMBOL_GPL(dccp_ioctl); 406 407 static int dccp_setsockopt_service(struct sock *sk, const __be32 service, 408 char __user *optval, unsigned int optlen) 409 { 410 struct dccp_sock *dp = dccp_sk(sk); 411 struct dccp_service_list *sl = NULL; 412 413 if (service == DCCP_SERVICE_INVALID_VALUE || 414 optlen > DCCP_SERVICE_LIST_MAX_LEN * sizeof(u32)) 415 return -EINVAL; 416 417 if (optlen > sizeof(service)) { 418 sl = kmalloc(optlen, GFP_KERNEL); 419 if (sl == NULL) 420 return -ENOMEM; 421 422 sl->dccpsl_nr = optlen / sizeof(u32) - 1; 423 if (copy_from_user(sl->dccpsl_list, 424 optval + sizeof(service), 425 optlen - sizeof(service)) || 426 dccp_list_has_service(sl, DCCP_SERVICE_INVALID_VALUE)) { 427 kfree(sl); 428 return -EFAULT; 429 } 430 } 431 432 lock_sock(sk); 433 dp->dccps_service = service; 434 435 kfree(dp->dccps_service_list); 436 437 dp->dccps_service_list = sl; 438 release_sock(sk); 439 return 0; 440 } 441 442 static int dccp_setsockopt_cscov(struct sock *sk, int cscov, bool rx) 443 { 444 u8 *list, len; 445 int i, rc; 446 447 if (cscov < 0 || cscov > 15) 448 return -EINVAL; 449 /* 450 * Populate a list of permissible values, in the range cscov...15. This 451 * is necessary since feature negotiation of single values only works if 452 * both sides incidentally choose the same value. Since the list starts 453 * lowest-value first, negotiation will pick the smallest shared value. 454 */ 455 if (cscov == 0) 456 return 0; 457 len = 16 - cscov; 458 459 list = kmalloc(len, GFP_KERNEL); 460 if (list == NULL) 461 return -ENOBUFS; 462 463 for (i = 0; i < len; i++) 464 list[i] = cscov++; 465 466 rc = dccp_feat_register_sp(sk, DCCPF_MIN_CSUM_COVER, rx, list, len); 467 468 if (rc == 0) { 469 if (rx) 470 dccp_sk(sk)->dccps_pcrlen = cscov; 471 else 472 dccp_sk(sk)->dccps_pcslen = cscov; 473 } 474 kfree(list); 475 return rc; 476 } 477 478 static int dccp_setsockopt_ccid(struct sock *sk, int type, 479 char __user *optval, unsigned int optlen) 480 { 481 u8 *val; 482 int rc = 0; 483 484 if (optlen < 1 || optlen > DCCP_FEAT_MAX_SP_VALS) 485 return -EINVAL; 486 487 val = memdup_user(optval, optlen); 488 if (IS_ERR(val)) 489 return PTR_ERR(val); 490 491 lock_sock(sk); 492 if (type == DCCP_SOCKOPT_TX_CCID || type == DCCP_SOCKOPT_CCID) 493 rc = dccp_feat_register_sp(sk, DCCPF_CCID, 1, val, optlen); 494 495 if (!rc && (type == DCCP_SOCKOPT_RX_CCID || type == DCCP_SOCKOPT_CCID)) 496 rc = dccp_feat_register_sp(sk, DCCPF_CCID, 0, val, optlen); 497 release_sock(sk); 498 499 kfree(val); 500 return rc; 501 } 502 503 static int do_dccp_setsockopt(struct sock *sk, int level, int optname, 504 char __user *optval, unsigned int optlen) 505 { 506 struct dccp_sock *dp = dccp_sk(sk); 507 int val, err = 0; 508 509 switch (optname) { 510 case DCCP_SOCKOPT_PACKET_SIZE: 511 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n"); 512 return 0; 513 case DCCP_SOCKOPT_CHANGE_L: 514 case DCCP_SOCKOPT_CHANGE_R: 515 DCCP_WARN("sockopt(CHANGE_L/R) is deprecated: fix your app\n"); 516 return 0; 517 case DCCP_SOCKOPT_CCID: 518 case DCCP_SOCKOPT_RX_CCID: 519 case DCCP_SOCKOPT_TX_CCID: 520 return dccp_setsockopt_ccid(sk, optname, optval, optlen); 521 } 522 523 if (optlen < (int)sizeof(int)) 524 return -EINVAL; 525 526 if (get_user(val, (int __user *)optval)) 527 return -EFAULT; 528 529 if (optname == DCCP_SOCKOPT_SERVICE) 530 return dccp_setsockopt_service(sk, val, optval, optlen); 531 532 lock_sock(sk); 533 switch (optname) { 534 case DCCP_SOCKOPT_SERVER_TIMEWAIT: 535 if (dp->dccps_role != DCCP_ROLE_SERVER) 536 err = -EOPNOTSUPP; 537 else 538 dp->dccps_server_timewait = (val != 0); 539 break; 540 case DCCP_SOCKOPT_SEND_CSCOV: 541 err = dccp_setsockopt_cscov(sk, val, false); 542 break; 543 case DCCP_SOCKOPT_RECV_CSCOV: 544 err = dccp_setsockopt_cscov(sk, val, true); 545 break; 546 case DCCP_SOCKOPT_QPOLICY_ID: 547 if (sk->sk_state != DCCP_CLOSED) 548 err = -EISCONN; 549 else if (val < 0 || val >= DCCPQ_POLICY_MAX) 550 err = -EINVAL; 551 else 552 dp->dccps_qpolicy = val; 553 break; 554 case DCCP_SOCKOPT_QPOLICY_TXQLEN: 555 if (val < 0) 556 err = -EINVAL; 557 else 558 dp->dccps_tx_qlen = val; 559 break; 560 default: 561 err = -ENOPROTOOPT; 562 break; 563 } 564 release_sock(sk); 565 566 return err; 567 } 568 569 int dccp_setsockopt(struct sock *sk, int level, int optname, 570 char __user *optval, unsigned int optlen) 571 { 572 if (level != SOL_DCCP) 573 return inet_csk(sk)->icsk_af_ops->setsockopt(sk, level, 574 optname, optval, 575 optlen); 576 return do_dccp_setsockopt(sk, level, optname, optval, optlen); 577 } 578 579 EXPORT_SYMBOL_GPL(dccp_setsockopt); 580 581 #ifdef CONFIG_COMPAT 582 int compat_dccp_setsockopt(struct sock *sk, int level, int optname, 583 char __user *optval, unsigned int optlen) 584 { 585 if (level != SOL_DCCP) 586 return inet_csk_compat_setsockopt(sk, level, optname, 587 optval, optlen); 588 return do_dccp_setsockopt(sk, level, optname, optval, optlen); 589 } 590 591 EXPORT_SYMBOL_GPL(compat_dccp_setsockopt); 592 #endif 593 594 static int dccp_getsockopt_service(struct sock *sk, int len, 595 __be32 __user *optval, 596 int __user *optlen) 597 { 598 const struct dccp_sock *dp = dccp_sk(sk); 599 const struct dccp_service_list *sl; 600 int err = -ENOENT, slen = 0, total_len = sizeof(u32); 601 602 lock_sock(sk); 603 if ((sl = dp->dccps_service_list) != NULL) { 604 slen = sl->dccpsl_nr * sizeof(u32); 605 total_len += slen; 606 } 607 608 err = -EINVAL; 609 if (total_len > len) 610 goto out; 611 612 err = 0; 613 if (put_user(total_len, optlen) || 614 put_user(dp->dccps_service, optval) || 615 (sl != NULL && copy_to_user(optval + 1, sl->dccpsl_list, slen))) 616 err = -EFAULT; 617 out: 618 release_sock(sk); 619 return err; 620 } 621 622 static int do_dccp_getsockopt(struct sock *sk, int level, int optname, 623 char __user *optval, int __user *optlen) 624 { 625 struct dccp_sock *dp; 626 int val, len; 627 628 if (get_user(len, optlen)) 629 return -EFAULT; 630 631 if (len < (int)sizeof(int)) 632 return -EINVAL; 633 634 dp = dccp_sk(sk); 635 636 switch (optname) { 637 case DCCP_SOCKOPT_PACKET_SIZE: 638 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n"); 639 return 0; 640 case DCCP_SOCKOPT_SERVICE: 641 return dccp_getsockopt_service(sk, len, 642 (__be32 __user *)optval, optlen); 643 case DCCP_SOCKOPT_GET_CUR_MPS: 644 val = dp->dccps_mss_cache; 645 break; 646 case DCCP_SOCKOPT_AVAILABLE_CCIDS: 647 return ccid_getsockopt_builtin_ccids(sk, len, optval, optlen); 648 case DCCP_SOCKOPT_TX_CCID: 649 val = ccid_get_current_tx_ccid(dp); 650 if (val < 0) 651 return -ENOPROTOOPT; 652 break; 653 case DCCP_SOCKOPT_RX_CCID: 654 val = ccid_get_current_rx_ccid(dp); 655 if (val < 0) 656 return -ENOPROTOOPT; 657 break; 658 case DCCP_SOCKOPT_SERVER_TIMEWAIT: 659 val = dp->dccps_server_timewait; 660 break; 661 case DCCP_SOCKOPT_SEND_CSCOV: 662 val = dp->dccps_pcslen; 663 break; 664 case DCCP_SOCKOPT_RECV_CSCOV: 665 val = dp->dccps_pcrlen; 666 break; 667 case DCCP_SOCKOPT_QPOLICY_ID: 668 val = dp->dccps_qpolicy; 669 break; 670 case DCCP_SOCKOPT_QPOLICY_TXQLEN: 671 val = dp->dccps_tx_qlen; 672 break; 673 case 128 ... 191: 674 return ccid_hc_rx_getsockopt(dp->dccps_hc_rx_ccid, sk, optname, 675 len, (u32 __user *)optval, optlen); 676 case 192 ... 255: 677 return ccid_hc_tx_getsockopt(dp->dccps_hc_tx_ccid, sk, optname, 678 len, (u32 __user *)optval, optlen); 679 default: 680 return -ENOPROTOOPT; 681 } 682 683 len = sizeof(val); 684 if (put_user(len, optlen) || copy_to_user(optval, &val, len)) 685 return -EFAULT; 686 687 return 0; 688 } 689 690 int dccp_getsockopt(struct sock *sk, int level, int optname, 691 char __user *optval, int __user *optlen) 692 { 693 if (level != SOL_DCCP) 694 return inet_csk(sk)->icsk_af_ops->getsockopt(sk, level, 695 optname, optval, 696 optlen); 697 return do_dccp_getsockopt(sk, level, optname, optval, optlen); 698 } 699 700 EXPORT_SYMBOL_GPL(dccp_getsockopt); 701 702 #ifdef CONFIG_COMPAT 703 int compat_dccp_getsockopt(struct sock *sk, int level, int optname, 704 char __user *optval, int __user *optlen) 705 { 706 if (level != SOL_DCCP) 707 return inet_csk_compat_getsockopt(sk, level, optname, 708 optval, optlen); 709 return do_dccp_getsockopt(sk, level, optname, optval, optlen); 710 } 711 712 EXPORT_SYMBOL_GPL(compat_dccp_getsockopt); 713 #endif 714 715 static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb) 716 { 717 struct cmsghdr *cmsg; 718 719 /* 720 * Assign an (opaque) qpolicy priority value to skb->priority. 721 * 722 * We are overloading this skb field for use with the qpolicy subystem. 723 * The skb->priority is normally used for the SO_PRIORITY option, which 724 * is initialised from sk_priority. Since the assignment of sk_priority 725 * to skb->priority happens later (on layer 3), we overload this field 726 * for use with queueing priorities as long as the skb is on layer 4. 727 * The default priority value (if nothing is set) is 0. 728 */ 729 skb->priority = 0; 730 731 for_each_cmsghdr(cmsg, msg) { 732 if (!CMSG_OK(msg, cmsg)) 733 return -EINVAL; 734 735 if (cmsg->cmsg_level != SOL_DCCP) 736 continue; 737 738 if (cmsg->cmsg_type <= DCCP_SCM_QPOLICY_MAX && 739 !dccp_qpolicy_param_ok(skb->sk, cmsg->cmsg_type)) 740 return -EINVAL; 741 742 switch (cmsg->cmsg_type) { 743 case DCCP_SCM_PRIORITY: 744 if (cmsg->cmsg_len != CMSG_LEN(sizeof(__u32))) 745 return -EINVAL; 746 skb->priority = *(__u32 *)CMSG_DATA(cmsg); 747 break; 748 default: 749 return -EINVAL; 750 } 751 } 752 return 0; 753 } 754 755 int dccp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 756 { 757 const struct dccp_sock *dp = dccp_sk(sk); 758 const int flags = msg->msg_flags; 759 const int noblock = flags & MSG_DONTWAIT; 760 struct sk_buff *skb; 761 int rc, size; 762 long timeo; 763 764 trace_dccp_probe(sk, len); 765 766 if (len > dp->dccps_mss_cache) 767 return -EMSGSIZE; 768 769 lock_sock(sk); 770 771 if (dccp_qpolicy_full(sk)) { 772 rc = -EAGAIN; 773 goto out_release; 774 } 775 776 timeo = sock_sndtimeo(sk, noblock); 777 778 /* 779 * We have to use sk_stream_wait_connect here to set sk_write_pending, 780 * so that the trick in dccp_rcv_request_sent_state_process. 781 */ 782 /* Wait for a connection to finish. */ 783 if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN)) 784 if ((rc = sk_stream_wait_connect(sk, &timeo)) != 0) 785 goto out_release; 786 787 size = sk->sk_prot->max_header + len; 788 release_sock(sk); 789 skb = sock_alloc_send_skb(sk, size, noblock, &rc); 790 lock_sock(sk); 791 if (skb == NULL) 792 goto out_release; 793 794 if (sk->sk_state == DCCP_CLOSED) { 795 rc = -ENOTCONN; 796 goto out_discard; 797 } 798 799 skb_reserve(skb, sk->sk_prot->max_header); 800 rc = memcpy_from_msg(skb_put(skb, len), msg, len); 801 if (rc != 0) 802 goto out_discard; 803 804 rc = dccp_msghdr_parse(msg, skb); 805 if (rc != 0) 806 goto out_discard; 807 808 dccp_qpolicy_push(sk, skb); 809 /* 810 * The xmit_timer is set if the TX CCID is rate-based and will expire 811 * when congestion control permits to release further packets into the 812 * network. Window-based CCIDs do not use this timer. 813 */ 814 if (!timer_pending(&dp->dccps_xmit_timer)) 815 dccp_write_xmit(sk); 816 out_release: 817 release_sock(sk); 818 return rc ? : len; 819 out_discard: 820 kfree_skb(skb); 821 goto out_release; 822 } 823 824 EXPORT_SYMBOL_GPL(dccp_sendmsg); 825 826 int dccp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock, 827 int flags, int *addr_len) 828 { 829 const struct dccp_hdr *dh; 830 long timeo; 831 832 lock_sock(sk); 833 834 if (sk->sk_state == DCCP_LISTEN) { 835 len = -ENOTCONN; 836 goto out; 837 } 838 839 timeo = sock_rcvtimeo(sk, nonblock); 840 841 do { 842 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue); 843 844 if (skb == NULL) 845 goto verify_sock_status; 846 847 dh = dccp_hdr(skb); 848 849 switch (dh->dccph_type) { 850 case DCCP_PKT_DATA: 851 case DCCP_PKT_DATAACK: 852 goto found_ok_skb; 853 854 case DCCP_PKT_CLOSE: 855 case DCCP_PKT_CLOSEREQ: 856 if (!(flags & MSG_PEEK)) 857 dccp_finish_passive_close(sk); 858 /* fall through */ 859 case DCCP_PKT_RESET: 860 dccp_pr_debug("found fin (%s) ok!\n", 861 dccp_packet_name(dh->dccph_type)); 862 len = 0; 863 goto found_fin_ok; 864 default: 865 dccp_pr_debug("packet_type=%s\n", 866 dccp_packet_name(dh->dccph_type)); 867 sk_eat_skb(sk, skb); 868 } 869 verify_sock_status: 870 if (sock_flag(sk, SOCK_DONE)) { 871 len = 0; 872 break; 873 } 874 875 if (sk->sk_err) { 876 len = sock_error(sk); 877 break; 878 } 879 880 if (sk->sk_shutdown & RCV_SHUTDOWN) { 881 len = 0; 882 break; 883 } 884 885 if (sk->sk_state == DCCP_CLOSED) { 886 if (!sock_flag(sk, SOCK_DONE)) { 887 /* This occurs when user tries to read 888 * from never connected socket. 889 */ 890 len = -ENOTCONN; 891 break; 892 } 893 len = 0; 894 break; 895 } 896 897 if (!timeo) { 898 len = -EAGAIN; 899 break; 900 } 901 902 if (signal_pending(current)) { 903 len = sock_intr_errno(timeo); 904 break; 905 } 906 907 sk_wait_data(sk, &timeo, NULL); 908 continue; 909 found_ok_skb: 910 if (len > skb->len) 911 len = skb->len; 912 else if (len < skb->len) 913 msg->msg_flags |= MSG_TRUNC; 914 915 if (skb_copy_datagram_msg(skb, 0, msg, len)) { 916 /* Exception. Bailout! */ 917 len = -EFAULT; 918 break; 919 } 920 if (flags & MSG_TRUNC) 921 len = skb->len; 922 found_fin_ok: 923 if (!(flags & MSG_PEEK)) 924 sk_eat_skb(sk, skb); 925 break; 926 } while (1); 927 out: 928 release_sock(sk); 929 return len; 930 } 931 932 EXPORT_SYMBOL_GPL(dccp_recvmsg); 933 934 int inet_dccp_listen(struct socket *sock, int backlog) 935 { 936 struct sock *sk = sock->sk; 937 unsigned char old_state; 938 int err; 939 940 lock_sock(sk); 941 942 err = -EINVAL; 943 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_DCCP) 944 goto out; 945 946 old_state = sk->sk_state; 947 if (!((1 << old_state) & (DCCPF_CLOSED | DCCPF_LISTEN))) 948 goto out; 949 950 sk->sk_max_ack_backlog = backlog; 951 /* Really, if the socket is already in listen state 952 * we can only allow the backlog to be adjusted. 953 */ 954 if (old_state != DCCP_LISTEN) { 955 /* 956 * FIXME: here it probably should be sk->sk_prot->listen_start 957 * see tcp_listen_start 958 */ 959 err = dccp_listen_start(sk, backlog); 960 if (err) 961 goto out; 962 } 963 err = 0; 964 965 out: 966 release_sock(sk); 967 return err; 968 } 969 970 EXPORT_SYMBOL_GPL(inet_dccp_listen); 971 972 static void dccp_terminate_connection(struct sock *sk) 973 { 974 u8 next_state = DCCP_CLOSED; 975 976 switch (sk->sk_state) { 977 case DCCP_PASSIVE_CLOSE: 978 case DCCP_PASSIVE_CLOSEREQ: 979 dccp_finish_passive_close(sk); 980 break; 981 case DCCP_PARTOPEN: 982 dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk); 983 inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); 984 /* fall through */ 985 case DCCP_OPEN: 986 dccp_send_close(sk, 1); 987 988 if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER && 989 !dccp_sk(sk)->dccps_server_timewait) 990 next_state = DCCP_ACTIVE_CLOSEREQ; 991 else 992 next_state = DCCP_CLOSING; 993 /* fall through */ 994 default: 995 dccp_set_state(sk, next_state); 996 } 997 } 998 999 void dccp_close(struct sock *sk, long timeout) 1000 { 1001 struct dccp_sock *dp = dccp_sk(sk); 1002 struct sk_buff *skb; 1003 u32 data_was_unread = 0; 1004 int state; 1005 1006 lock_sock(sk); 1007 1008 sk->sk_shutdown = SHUTDOWN_MASK; 1009 1010 if (sk->sk_state == DCCP_LISTEN) { 1011 dccp_set_state(sk, DCCP_CLOSED); 1012 1013 /* Special case. */ 1014 inet_csk_listen_stop(sk); 1015 1016 goto adjudge_to_death; 1017 } 1018 1019 sk_stop_timer(sk, &dp->dccps_xmit_timer); 1020 1021 /* 1022 * We need to flush the recv. buffs. We do this only on the 1023 * descriptor close, not protocol-sourced closes, because the 1024 *reader process may not have drained the data yet! 1025 */ 1026 while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) { 1027 data_was_unread += skb->len; 1028 __kfree_skb(skb); 1029 } 1030 1031 /* If socket has been already reset kill it. */ 1032 if (sk->sk_state == DCCP_CLOSED) 1033 goto adjudge_to_death; 1034 1035 if (data_was_unread) { 1036 /* Unread data was tossed, send an appropriate Reset Code */ 1037 DCCP_WARN("ABORT with %u bytes unread\n", data_was_unread); 1038 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED); 1039 dccp_set_state(sk, DCCP_CLOSED); 1040 } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) { 1041 /* Check zero linger _after_ checking for unread data. */ 1042 sk->sk_prot->disconnect(sk, 0); 1043 } else if (sk->sk_state != DCCP_CLOSED) { 1044 /* 1045 * Normal connection termination. May need to wait if there are 1046 * still packets in the TX queue that are delayed by the CCID. 1047 */ 1048 dccp_flush_write_queue(sk, &timeout); 1049 dccp_terminate_connection(sk); 1050 } 1051 1052 /* 1053 * Flush write queue. This may be necessary in several cases: 1054 * - we have been closed by the peer but still have application data; 1055 * - abortive termination (unread data or zero linger time), 1056 * - normal termination but queue could not be flushed within time limit 1057 */ 1058 __skb_queue_purge(&sk->sk_write_queue); 1059 1060 sk_stream_wait_close(sk, timeout); 1061 1062 adjudge_to_death: 1063 state = sk->sk_state; 1064 sock_hold(sk); 1065 sock_orphan(sk); 1066 1067 /* 1068 * It is the last release_sock in its life. It will remove backlog. 1069 */ 1070 release_sock(sk); 1071 /* 1072 * Now socket is owned by kernel and we acquire BH lock 1073 * to finish close. No need to check for user refs. 1074 */ 1075 local_bh_disable(); 1076 bh_lock_sock(sk); 1077 WARN_ON(sock_owned_by_user(sk)); 1078 1079 percpu_counter_inc(sk->sk_prot->orphan_count); 1080 1081 /* Have we already been destroyed by a softirq or backlog? */ 1082 if (state != DCCP_CLOSED && sk->sk_state == DCCP_CLOSED) 1083 goto out; 1084 1085 if (sk->sk_state == DCCP_CLOSED) 1086 inet_csk_destroy_sock(sk); 1087 1088 /* Otherwise, socket is reprieved until protocol close. */ 1089 1090 out: 1091 bh_unlock_sock(sk); 1092 local_bh_enable(); 1093 sock_put(sk); 1094 } 1095 1096 EXPORT_SYMBOL_GPL(dccp_close); 1097 1098 void dccp_shutdown(struct sock *sk, int how) 1099 { 1100 dccp_pr_debug("called shutdown(%x)\n", how); 1101 } 1102 1103 EXPORT_SYMBOL_GPL(dccp_shutdown); 1104 1105 static inline int __init dccp_mib_init(void) 1106 { 1107 dccp_statistics = alloc_percpu(struct dccp_mib); 1108 if (!dccp_statistics) 1109 return -ENOMEM; 1110 return 0; 1111 } 1112 1113 static inline void dccp_mib_exit(void) 1114 { 1115 free_percpu(dccp_statistics); 1116 } 1117 1118 static int thash_entries; 1119 module_param(thash_entries, int, 0444); 1120 MODULE_PARM_DESC(thash_entries, "Number of ehash buckets"); 1121 1122 #ifdef CONFIG_IP_DCCP_DEBUG 1123 bool dccp_debug; 1124 module_param(dccp_debug, bool, 0644); 1125 MODULE_PARM_DESC(dccp_debug, "Enable debug messages"); 1126 1127 EXPORT_SYMBOL_GPL(dccp_debug); 1128 #endif 1129 1130 static int __init dccp_init(void) 1131 { 1132 unsigned long goal; 1133 unsigned long nr_pages = totalram_pages(); 1134 int ehash_order, bhash_order, i; 1135 int rc; 1136 1137 BUILD_BUG_ON(sizeof(struct dccp_skb_cb) > 1138 FIELD_SIZEOF(struct sk_buff, cb)); 1139 rc = percpu_counter_init(&dccp_orphan_count, 0, GFP_KERNEL); 1140 if (rc) 1141 goto out_fail; 1142 inet_hashinfo_init(&dccp_hashinfo); 1143 rc = inet_hashinfo2_init_mod(&dccp_hashinfo); 1144 if (rc) 1145 goto out_fail; 1146 rc = -ENOBUFS; 1147 dccp_hashinfo.bind_bucket_cachep = 1148 kmem_cache_create("dccp_bind_bucket", 1149 sizeof(struct inet_bind_bucket), 0, 1150 SLAB_HWCACHE_ALIGN, NULL); 1151 if (!dccp_hashinfo.bind_bucket_cachep) 1152 goto out_free_percpu; 1153 1154 /* 1155 * Size and allocate the main established and bind bucket 1156 * hash tables. 1157 * 1158 * The methodology is similar to that of the buffer cache. 1159 */ 1160 if (nr_pages >= (128 * 1024)) 1161 goal = nr_pages >> (21 - PAGE_SHIFT); 1162 else 1163 goal = nr_pages >> (23 - PAGE_SHIFT); 1164 1165 if (thash_entries) 1166 goal = (thash_entries * 1167 sizeof(struct inet_ehash_bucket)) >> PAGE_SHIFT; 1168 for (ehash_order = 0; (1UL << ehash_order) < goal; ehash_order++) 1169 ; 1170 do { 1171 unsigned long hash_size = (1UL << ehash_order) * PAGE_SIZE / 1172 sizeof(struct inet_ehash_bucket); 1173 1174 while (hash_size & (hash_size - 1)) 1175 hash_size--; 1176 dccp_hashinfo.ehash_mask = hash_size - 1; 1177 dccp_hashinfo.ehash = (struct inet_ehash_bucket *) 1178 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, ehash_order); 1179 } while (!dccp_hashinfo.ehash && --ehash_order > 0); 1180 1181 if (!dccp_hashinfo.ehash) { 1182 DCCP_CRIT("Failed to allocate DCCP established hash table"); 1183 goto out_free_bind_bucket_cachep; 1184 } 1185 1186 for (i = 0; i <= dccp_hashinfo.ehash_mask; i++) 1187 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo.ehash[i].chain, i); 1188 1189 if (inet_ehash_locks_alloc(&dccp_hashinfo)) 1190 goto out_free_dccp_ehash; 1191 1192 bhash_order = ehash_order; 1193 1194 do { 1195 dccp_hashinfo.bhash_size = (1UL << bhash_order) * PAGE_SIZE / 1196 sizeof(struct inet_bind_hashbucket); 1197 if ((dccp_hashinfo.bhash_size > (64 * 1024)) && 1198 bhash_order > 0) 1199 continue; 1200 dccp_hashinfo.bhash = (struct inet_bind_hashbucket *) 1201 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, bhash_order); 1202 } while (!dccp_hashinfo.bhash && --bhash_order >= 0); 1203 1204 if (!dccp_hashinfo.bhash) { 1205 DCCP_CRIT("Failed to allocate DCCP bind hash table"); 1206 goto out_free_dccp_locks; 1207 } 1208 1209 for (i = 0; i < dccp_hashinfo.bhash_size; i++) { 1210 spin_lock_init(&dccp_hashinfo.bhash[i].lock); 1211 INIT_HLIST_HEAD(&dccp_hashinfo.bhash[i].chain); 1212 } 1213 1214 rc = dccp_mib_init(); 1215 if (rc) 1216 goto out_free_dccp_bhash; 1217 1218 rc = dccp_ackvec_init(); 1219 if (rc) 1220 goto out_free_dccp_mib; 1221 1222 rc = dccp_sysctl_init(); 1223 if (rc) 1224 goto out_ackvec_exit; 1225 1226 rc = ccid_initialize_builtins(); 1227 if (rc) 1228 goto out_sysctl_exit; 1229 1230 dccp_timestamping_init(); 1231 1232 return 0; 1233 1234 out_sysctl_exit: 1235 dccp_sysctl_exit(); 1236 out_ackvec_exit: 1237 dccp_ackvec_exit(); 1238 out_free_dccp_mib: 1239 dccp_mib_exit(); 1240 out_free_dccp_bhash: 1241 free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order); 1242 out_free_dccp_locks: 1243 inet_ehash_locks_free(&dccp_hashinfo); 1244 out_free_dccp_ehash: 1245 free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order); 1246 out_free_bind_bucket_cachep: 1247 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep); 1248 out_free_percpu: 1249 percpu_counter_destroy(&dccp_orphan_count); 1250 out_fail: 1251 dccp_hashinfo.bhash = NULL; 1252 dccp_hashinfo.ehash = NULL; 1253 dccp_hashinfo.bind_bucket_cachep = NULL; 1254 return rc; 1255 } 1256 1257 static void __exit dccp_fini(void) 1258 { 1259 ccid_cleanup_builtins(); 1260 dccp_mib_exit(); 1261 free_pages((unsigned long)dccp_hashinfo.bhash, 1262 get_order(dccp_hashinfo.bhash_size * 1263 sizeof(struct inet_bind_hashbucket))); 1264 free_pages((unsigned long)dccp_hashinfo.ehash, 1265 get_order((dccp_hashinfo.ehash_mask + 1) * 1266 sizeof(struct inet_ehash_bucket))); 1267 inet_ehash_locks_free(&dccp_hashinfo); 1268 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep); 1269 dccp_ackvec_exit(); 1270 dccp_sysctl_exit(); 1271 percpu_counter_destroy(&dccp_orphan_count); 1272 } 1273 1274 module_init(dccp_init); 1275 module_exit(dccp_fini); 1276 1277 MODULE_LICENSE("GPL"); 1278 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>"); 1279 MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol"); 1280