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_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly; 42 43 EXPORT_SYMBOL_GPL(dccp_statistics); 44 45 struct percpu_counter dccp_orphan_count; 46 EXPORT_SYMBOL_GPL(dccp_orphan_count); 47 48 struct inet_hashinfo dccp_hashinfo; 49 EXPORT_SYMBOL_GPL(dccp_hashinfo); 50 51 /* the maximum queue length for tx in packets. 0 is no limit */ 52 int sysctl_dccp_tx_qlen __read_mostly = 5; 53 54 #ifdef CONFIG_IP_DCCP_DEBUG 55 static const char *dccp_state_name(const int state) 56 { 57 static const char *const dccp_state_names[] = { 58 [DCCP_OPEN] = "OPEN", 59 [DCCP_REQUESTING] = "REQUESTING", 60 [DCCP_PARTOPEN] = "PARTOPEN", 61 [DCCP_LISTEN] = "LISTEN", 62 [DCCP_RESPOND] = "RESPOND", 63 [DCCP_CLOSING] = "CLOSING", 64 [DCCP_ACTIVE_CLOSEREQ] = "CLOSEREQ", 65 [DCCP_PASSIVE_CLOSE] = "PASSIVE_CLOSE", 66 [DCCP_PASSIVE_CLOSEREQ] = "PASSIVE_CLOSEREQ", 67 [DCCP_TIME_WAIT] = "TIME_WAIT", 68 [DCCP_CLOSED] = "CLOSED", 69 }; 70 71 if (state >= DCCP_MAX_STATES) 72 return "INVALID STATE!"; 73 else 74 return dccp_state_names[state]; 75 } 76 #endif 77 78 void dccp_set_state(struct sock *sk, const int state) 79 { 80 const int oldstate = sk->sk_state; 81 82 dccp_pr_debug("%s(%p) %s --> %s\n", dccp_role(sk), sk, 83 dccp_state_name(oldstate), dccp_state_name(state)); 84 WARN_ON(state == oldstate); 85 86 switch (state) { 87 case DCCP_OPEN: 88 if (oldstate != DCCP_OPEN) 89 DCCP_INC_STATS(DCCP_MIB_CURRESTAB); 90 /* Client retransmits all Confirm options until entering OPEN */ 91 if (oldstate == DCCP_PARTOPEN) 92 dccp_feat_list_purge(&dccp_sk(sk)->dccps_featneg); 93 break; 94 95 case DCCP_CLOSED: 96 if (oldstate == DCCP_OPEN || oldstate == DCCP_ACTIVE_CLOSEREQ || 97 oldstate == DCCP_CLOSING) 98 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS); 99 100 sk->sk_prot->unhash(sk); 101 if (inet_csk(sk)->icsk_bind_hash != NULL && 102 !(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) 103 inet_put_port(sk); 104 /* fall through */ 105 default: 106 if (oldstate == DCCP_OPEN) 107 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB); 108 } 109 110 /* Change state AFTER socket is unhashed to avoid closed 111 * socket sitting in hash tables. 112 */ 113 sk->sk_state = state; 114 } 115 116 EXPORT_SYMBOL_GPL(dccp_set_state); 117 118 static void dccp_finish_passive_close(struct sock *sk) 119 { 120 switch (sk->sk_state) { 121 case DCCP_PASSIVE_CLOSE: 122 /* Node (client or server) has received Close packet. */ 123 dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED); 124 dccp_set_state(sk, DCCP_CLOSED); 125 break; 126 case DCCP_PASSIVE_CLOSEREQ: 127 /* 128 * Client received CloseReq. We set the `active' flag so that 129 * dccp_send_close() retransmits the Close as per RFC 4340, 8.3. 130 */ 131 dccp_send_close(sk, 1); 132 dccp_set_state(sk, DCCP_CLOSING); 133 } 134 } 135 136 void dccp_done(struct sock *sk) 137 { 138 dccp_set_state(sk, DCCP_CLOSED); 139 dccp_clear_xmit_timers(sk); 140 141 sk->sk_shutdown = SHUTDOWN_MASK; 142 143 if (!sock_flag(sk, SOCK_DEAD)) 144 sk->sk_state_change(sk); 145 else 146 inet_csk_destroy_sock(sk); 147 } 148 149 EXPORT_SYMBOL_GPL(dccp_done); 150 151 const char *dccp_packet_name(const int type) 152 { 153 static const char *const dccp_packet_names[] = { 154 [DCCP_PKT_REQUEST] = "REQUEST", 155 [DCCP_PKT_RESPONSE] = "RESPONSE", 156 [DCCP_PKT_DATA] = "DATA", 157 [DCCP_PKT_ACK] = "ACK", 158 [DCCP_PKT_DATAACK] = "DATAACK", 159 [DCCP_PKT_CLOSEREQ] = "CLOSEREQ", 160 [DCCP_PKT_CLOSE] = "CLOSE", 161 [DCCP_PKT_RESET] = "RESET", 162 [DCCP_PKT_SYNC] = "SYNC", 163 [DCCP_PKT_SYNCACK] = "SYNCACK", 164 }; 165 166 if (type >= DCCP_NR_PKT_TYPES) 167 return "INVALID"; 168 else 169 return dccp_packet_names[type]; 170 } 171 172 EXPORT_SYMBOL_GPL(dccp_packet_name); 173 174 static void dccp_sk_destruct(struct sock *sk) 175 { 176 struct dccp_sock *dp = dccp_sk(sk); 177 178 ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk); 179 dp->dccps_hc_tx_ccid = NULL; 180 inet_sock_destruct(sk); 181 } 182 183 int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized) 184 { 185 struct dccp_sock *dp = dccp_sk(sk); 186 struct inet_connection_sock *icsk = inet_csk(sk); 187 188 icsk->icsk_rto = DCCP_TIMEOUT_INIT; 189 icsk->icsk_syn_retries = sysctl_dccp_request_retries; 190 sk->sk_state = DCCP_CLOSED; 191 sk->sk_write_space = dccp_write_space; 192 sk->sk_destruct = dccp_sk_destruct; 193 icsk->icsk_sync_mss = dccp_sync_mss; 194 dp->dccps_mss_cache = 536; 195 dp->dccps_rate_last = jiffies; 196 dp->dccps_role = DCCP_ROLE_UNDEFINED; 197 dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT; 198 dp->dccps_tx_qlen = sysctl_dccp_tx_qlen; 199 200 dccp_init_xmit_timers(sk); 201 202 INIT_LIST_HEAD(&dp->dccps_featneg); 203 /* control socket doesn't need feat nego */ 204 if (likely(ctl_sock_initialized)) 205 return dccp_feat_init(sk); 206 return 0; 207 } 208 209 EXPORT_SYMBOL_GPL(dccp_init_sock); 210 211 void dccp_destroy_sock(struct sock *sk) 212 { 213 struct dccp_sock *dp = dccp_sk(sk); 214 215 __skb_queue_purge(&sk->sk_write_queue); 216 if (sk->sk_send_head != NULL) { 217 kfree_skb(sk->sk_send_head); 218 sk->sk_send_head = NULL; 219 } 220 221 /* Clean up a referenced DCCP bind bucket. */ 222 if (inet_csk(sk)->icsk_bind_hash != NULL) 223 inet_put_port(sk); 224 225 kfree(dp->dccps_service_list); 226 dp->dccps_service_list = NULL; 227 228 if (dp->dccps_hc_rx_ackvec != NULL) { 229 dccp_ackvec_free(dp->dccps_hc_rx_ackvec); 230 dp->dccps_hc_rx_ackvec = NULL; 231 } 232 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk); 233 dp->dccps_hc_rx_ccid = NULL; 234 235 /* clean up feature negotiation state */ 236 dccp_feat_list_purge(&dp->dccps_featneg); 237 } 238 239 EXPORT_SYMBOL_GPL(dccp_destroy_sock); 240 241 static inline int dccp_listen_start(struct sock *sk, int backlog) 242 { 243 struct dccp_sock *dp = dccp_sk(sk); 244 245 dp->dccps_role = DCCP_ROLE_LISTEN; 246 /* do not start to listen if feature negotiation setup fails */ 247 if (dccp_feat_finalise_settings(dp)) 248 return -EPROTO; 249 return inet_csk_listen_start(sk, backlog); 250 } 251 252 static inline int dccp_need_reset(int state) 253 { 254 return state != DCCP_CLOSED && state != DCCP_LISTEN && 255 state != DCCP_REQUESTING; 256 } 257 258 int dccp_disconnect(struct sock *sk, int flags) 259 { 260 struct inet_connection_sock *icsk = inet_csk(sk); 261 struct inet_sock *inet = inet_sk(sk); 262 struct dccp_sock *dp = dccp_sk(sk); 263 int err = 0; 264 const int old_state = sk->sk_state; 265 266 if (old_state != DCCP_CLOSED) 267 dccp_set_state(sk, DCCP_CLOSED); 268 269 /* 270 * This corresponds to the ABORT function of RFC793, sec. 3.8 271 * TCP uses a RST segment, DCCP a Reset packet with Code 2, "Aborted". 272 */ 273 if (old_state == DCCP_LISTEN) { 274 inet_csk_listen_stop(sk); 275 } else if (dccp_need_reset(old_state)) { 276 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED); 277 sk->sk_err = ECONNRESET; 278 } else if (old_state == DCCP_REQUESTING) 279 sk->sk_err = ECONNRESET; 280 281 dccp_clear_xmit_timers(sk); 282 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk); 283 ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk); 284 dp->dccps_hc_rx_ccid = NULL; 285 dp->dccps_hc_tx_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 err; 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 unsigned int dccp_poll(struct file *file, struct socket *sock, 322 poll_table *wait) 323 { 324 unsigned int mask; 325 struct sock *sk = sock->sk; 326 327 sock_poll_wait(file, sk_sleep(sk), 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 = POLLERR; 339 340 if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == DCCP_CLOSED) 341 mask |= POLLHUP; 342 if (sk->sk_shutdown & RCV_SHUTDOWN) 343 mask |= POLLIN | POLLRDNORM | POLLRDHUP; 344 345 /* Connected? */ 346 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) { 347 if (atomic_read(&sk->sk_rmem_alloc) > 0) 348 mask |= POLLIN | POLLRDNORM; 349 350 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 351 if (sk_stream_is_writeable(sk)) { 352 mask |= POLLOUT | POLLWRNORM; 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 |= POLLOUT | POLLWRNORM; 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 if (len > dp->dccps_mss_cache) 765 return -EMSGSIZE; 766 767 lock_sock(sk); 768 769 if (dccp_qpolicy_full(sk)) { 770 rc = -EAGAIN; 771 goto out_release; 772 } 773 774 timeo = sock_sndtimeo(sk, noblock); 775 776 /* 777 * We have to use sk_stream_wait_connect here to set sk_write_pending, 778 * so that the trick in dccp_rcv_request_sent_state_process. 779 */ 780 /* Wait for a connection to finish. */ 781 if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN)) 782 if ((rc = sk_stream_wait_connect(sk, &timeo)) != 0) 783 goto out_release; 784 785 size = sk->sk_prot->max_header + len; 786 release_sock(sk); 787 skb = sock_alloc_send_skb(sk, size, noblock, &rc); 788 lock_sock(sk); 789 if (skb == NULL) 790 goto out_release; 791 792 skb_reserve(skb, sk->sk_prot->max_header); 793 rc = memcpy_from_msg(skb_put(skb, len), msg, len); 794 if (rc != 0) 795 goto out_discard; 796 797 rc = dccp_msghdr_parse(msg, skb); 798 if (rc != 0) 799 goto out_discard; 800 801 dccp_qpolicy_push(sk, skb); 802 /* 803 * The xmit_timer is set if the TX CCID is rate-based and will expire 804 * when congestion control permits to release further packets into the 805 * network. Window-based CCIDs do not use this timer. 806 */ 807 if (!timer_pending(&dp->dccps_xmit_timer)) 808 dccp_write_xmit(sk); 809 out_release: 810 release_sock(sk); 811 return rc ? : len; 812 out_discard: 813 kfree_skb(skb); 814 goto out_release; 815 } 816 817 EXPORT_SYMBOL_GPL(dccp_sendmsg); 818 819 int dccp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock, 820 int flags, int *addr_len) 821 { 822 const struct dccp_hdr *dh; 823 long timeo; 824 825 lock_sock(sk); 826 827 if (sk->sk_state == DCCP_LISTEN) { 828 len = -ENOTCONN; 829 goto out; 830 } 831 832 timeo = sock_rcvtimeo(sk, nonblock); 833 834 do { 835 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue); 836 837 if (skb == NULL) 838 goto verify_sock_status; 839 840 dh = dccp_hdr(skb); 841 842 switch (dh->dccph_type) { 843 case DCCP_PKT_DATA: 844 case DCCP_PKT_DATAACK: 845 goto found_ok_skb; 846 847 case DCCP_PKT_CLOSE: 848 case DCCP_PKT_CLOSEREQ: 849 if (!(flags & MSG_PEEK)) 850 dccp_finish_passive_close(sk); 851 /* fall through */ 852 case DCCP_PKT_RESET: 853 dccp_pr_debug("found fin (%s) ok!\n", 854 dccp_packet_name(dh->dccph_type)); 855 len = 0; 856 goto found_fin_ok; 857 default: 858 dccp_pr_debug("packet_type=%s\n", 859 dccp_packet_name(dh->dccph_type)); 860 sk_eat_skb(sk, skb); 861 } 862 verify_sock_status: 863 if (sock_flag(sk, SOCK_DONE)) { 864 len = 0; 865 break; 866 } 867 868 if (sk->sk_err) { 869 len = sock_error(sk); 870 break; 871 } 872 873 if (sk->sk_shutdown & RCV_SHUTDOWN) { 874 len = 0; 875 break; 876 } 877 878 if (sk->sk_state == DCCP_CLOSED) { 879 if (!sock_flag(sk, SOCK_DONE)) { 880 /* This occurs when user tries to read 881 * from never connected socket. 882 */ 883 len = -ENOTCONN; 884 break; 885 } 886 len = 0; 887 break; 888 } 889 890 if (!timeo) { 891 len = -EAGAIN; 892 break; 893 } 894 895 if (signal_pending(current)) { 896 len = sock_intr_errno(timeo); 897 break; 898 } 899 900 sk_wait_data(sk, &timeo, NULL); 901 continue; 902 found_ok_skb: 903 if (len > skb->len) 904 len = skb->len; 905 else if (len < skb->len) 906 msg->msg_flags |= MSG_TRUNC; 907 908 if (skb_copy_datagram_msg(skb, 0, msg, len)) { 909 /* Exception. Bailout! */ 910 len = -EFAULT; 911 break; 912 } 913 if (flags & MSG_TRUNC) 914 len = skb->len; 915 found_fin_ok: 916 if (!(flags & MSG_PEEK)) 917 sk_eat_skb(sk, skb); 918 break; 919 } while (1); 920 out: 921 release_sock(sk); 922 return len; 923 } 924 925 EXPORT_SYMBOL_GPL(dccp_recvmsg); 926 927 int inet_dccp_listen(struct socket *sock, int backlog) 928 { 929 struct sock *sk = sock->sk; 930 unsigned char old_state; 931 int err; 932 933 lock_sock(sk); 934 935 err = -EINVAL; 936 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_DCCP) 937 goto out; 938 939 old_state = sk->sk_state; 940 if (!((1 << old_state) & (DCCPF_CLOSED | DCCPF_LISTEN))) 941 goto out; 942 943 /* Really, if the socket is already in listen state 944 * we can only allow the backlog to be adjusted. 945 */ 946 if (old_state != DCCP_LISTEN) { 947 /* 948 * FIXME: here it probably should be sk->sk_prot->listen_start 949 * see tcp_listen_start 950 */ 951 err = dccp_listen_start(sk, backlog); 952 if (err) 953 goto out; 954 } 955 sk->sk_max_ack_backlog = backlog; 956 err = 0; 957 958 out: 959 release_sock(sk); 960 return err; 961 } 962 963 EXPORT_SYMBOL_GPL(inet_dccp_listen); 964 965 static void dccp_terminate_connection(struct sock *sk) 966 { 967 u8 next_state = DCCP_CLOSED; 968 969 switch (sk->sk_state) { 970 case DCCP_PASSIVE_CLOSE: 971 case DCCP_PASSIVE_CLOSEREQ: 972 dccp_finish_passive_close(sk); 973 break; 974 case DCCP_PARTOPEN: 975 dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk); 976 inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); 977 /* fall through */ 978 case DCCP_OPEN: 979 dccp_send_close(sk, 1); 980 981 if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER && 982 !dccp_sk(sk)->dccps_server_timewait) 983 next_state = DCCP_ACTIVE_CLOSEREQ; 984 else 985 next_state = DCCP_CLOSING; 986 /* fall through */ 987 default: 988 dccp_set_state(sk, next_state); 989 } 990 } 991 992 void dccp_close(struct sock *sk, long timeout) 993 { 994 struct dccp_sock *dp = dccp_sk(sk); 995 struct sk_buff *skb; 996 u32 data_was_unread = 0; 997 int state; 998 999 lock_sock(sk); 1000 1001 sk->sk_shutdown = SHUTDOWN_MASK; 1002 1003 if (sk->sk_state == DCCP_LISTEN) { 1004 dccp_set_state(sk, DCCP_CLOSED); 1005 1006 /* Special case. */ 1007 inet_csk_listen_stop(sk); 1008 1009 goto adjudge_to_death; 1010 } 1011 1012 sk_stop_timer(sk, &dp->dccps_xmit_timer); 1013 1014 /* 1015 * We need to flush the recv. buffs. We do this only on the 1016 * descriptor close, not protocol-sourced closes, because the 1017 *reader process may not have drained the data yet! 1018 */ 1019 while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) { 1020 data_was_unread += skb->len; 1021 __kfree_skb(skb); 1022 } 1023 1024 /* If socket has been already reset kill it. */ 1025 if (sk->sk_state == DCCP_CLOSED) 1026 goto adjudge_to_death; 1027 1028 if (data_was_unread) { 1029 /* Unread data was tossed, send an appropriate Reset Code */ 1030 DCCP_WARN("ABORT with %u bytes unread\n", data_was_unread); 1031 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED); 1032 dccp_set_state(sk, DCCP_CLOSED); 1033 } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) { 1034 /* Check zero linger _after_ checking for unread data. */ 1035 sk->sk_prot->disconnect(sk, 0); 1036 } else if (sk->sk_state != DCCP_CLOSED) { 1037 /* 1038 * Normal connection termination. May need to wait if there are 1039 * still packets in the TX queue that are delayed by the CCID. 1040 */ 1041 dccp_flush_write_queue(sk, &timeout); 1042 dccp_terminate_connection(sk); 1043 } 1044 1045 /* 1046 * Flush write queue. This may be necessary in several cases: 1047 * - we have been closed by the peer but still have application data; 1048 * - abortive termination (unread data or zero linger time), 1049 * - normal termination but queue could not be flushed within time limit 1050 */ 1051 __skb_queue_purge(&sk->sk_write_queue); 1052 1053 sk_stream_wait_close(sk, timeout); 1054 1055 adjudge_to_death: 1056 state = sk->sk_state; 1057 sock_hold(sk); 1058 sock_orphan(sk); 1059 1060 /* 1061 * It is the last release_sock in its life. It will remove backlog. 1062 */ 1063 release_sock(sk); 1064 /* 1065 * Now socket is owned by kernel and we acquire BH lock 1066 * to finish close. No need to check for user refs. 1067 */ 1068 local_bh_disable(); 1069 bh_lock_sock(sk); 1070 WARN_ON(sock_owned_by_user(sk)); 1071 1072 percpu_counter_inc(sk->sk_prot->orphan_count); 1073 1074 /* Have we already been destroyed by a softirq or backlog? */ 1075 if (state != DCCP_CLOSED && sk->sk_state == DCCP_CLOSED) 1076 goto out; 1077 1078 if (sk->sk_state == DCCP_CLOSED) 1079 inet_csk_destroy_sock(sk); 1080 1081 /* Otherwise, socket is reprieved until protocol close. */ 1082 1083 out: 1084 bh_unlock_sock(sk); 1085 local_bh_enable(); 1086 sock_put(sk); 1087 } 1088 1089 EXPORT_SYMBOL_GPL(dccp_close); 1090 1091 void dccp_shutdown(struct sock *sk, int how) 1092 { 1093 dccp_pr_debug("called shutdown(%x)\n", how); 1094 } 1095 1096 EXPORT_SYMBOL_GPL(dccp_shutdown); 1097 1098 static inline int __init dccp_mib_init(void) 1099 { 1100 dccp_statistics = alloc_percpu(struct dccp_mib); 1101 if (!dccp_statistics) 1102 return -ENOMEM; 1103 return 0; 1104 } 1105 1106 static inline void dccp_mib_exit(void) 1107 { 1108 free_percpu(dccp_statistics); 1109 } 1110 1111 static int thash_entries; 1112 module_param(thash_entries, int, 0444); 1113 MODULE_PARM_DESC(thash_entries, "Number of ehash buckets"); 1114 1115 #ifdef CONFIG_IP_DCCP_DEBUG 1116 bool dccp_debug; 1117 module_param(dccp_debug, bool, 0644); 1118 MODULE_PARM_DESC(dccp_debug, "Enable debug messages"); 1119 1120 EXPORT_SYMBOL_GPL(dccp_debug); 1121 #endif 1122 1123 static int __init dccp_init(void) 1124 { 1125 unsigned long goal; 1126 int ehash_order, bhash_order, i; 1127 int rc; 1128 1129 BUILD_BUG_ON(sizeof(struct dccp_skb_cb) > 1130 FIELD_SIZEOF(struct sk_buff, cb)); 1131 rc = percpu_counter_init(&dccp_orphan_count, 0, GFP_KERNEL); 1132 if (rc) 1133 goto out_fail; 1134 rc = -ENOBUFS; 1135 inet_hashinfo_init(&dccp_hashinfo); 1136 dccp_hashinfo.bind_bucket_cachep = 1137 kmem_cache_create("dccp_bind_bucket", 1138 sizeof(struct inet_bind_bucket), 0, 1139 SLAB_HWCACHE_ALIGN, NULL); 1140 if (!dccp_hashinfo.bind_bucket_cachep) 1141 goto out_free_percpu; 1142 1143 /* 1144 * Size and allocate the main established and bind bucket 1145 * hash tables. 1146 * 1147 * The methodology is similar to that of the buffer cache. 1148 */ 1149 if (totalram_pages >= (128 * 1024)) 1150 goal = totalram_pages >> (21 - PAGE_SHIFT); 1151 else 1152 goal = totalram_pages >> (23 - PAGE_SHIFT); 1153 1154 if (thash_entries) 1155 goal = (thash_entries * 1156 sizeof(struct inet_ehash_bucket)) >> PAGE_SHIFT; 1157 for (ehash_order = 0; (1UL << ehash_order) < goal; ehash_order++) 1158 ; 1159 do { 1160 unsigned long hash_size = (1UL << ehash_order) * PAGE_SIZE / 1161 sizeof(struct inet_ehash_bucket); 1162 1163 while (hash_size & (hash_size - 1)) 1164 hash_size--; 1165 dccp_hashinfo.ehash_mask = hash_size - 1; 1166 dccp_hashinfo.ehash = (struct inet_ehash_bucket *) 1167 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, ehash_order); 1168 } while (!dccp_hashinfo.ehash && --ehash_order > 0); 1169 1170 if (!dccp_hashinfo.ehash) { 1171 DCCP_CRIT("Failed to allocate DCCP established hash table"); 1172 goto out_free_bind_bucket_cachep; 1173 } 1174 1175 for (i = 0; i <= dccp_hashinfo.ehash_mask; i++) 1176 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo.ehash[i].chain, i); 1177 1178 if (inet_ehash_locks_alloc(&dccp_hashinfo)) 1179 goto out_free_dccp_ehash; 1180 1181 bhash_order = ehash_order; 1182 1183 do { 1184 dccp_hashinfo.bhash_size = (1UL << bhash_order) * PAGE_SIZE / 1185 sizeof(struct inet_bind_hashbucket); 1186 if ((dccp_hashinfo.bhash_size > (64 * 1024)) && 1187 bhash_order > 0) 1188 continue; 1189 dccp_hashinfo.bhash = (struct inet_bind_hashbucket *) 1190 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, bhash_order); 1191 } while (!dccp_hashinfo.bhash && --bhash_order >= 0); 1192 1193 if (!dccp_hashinfo.bhash) { 1194 DCCP_CRIT("Failed to allocate DCCP bind hash table"); 1195 goto out_free_dccp_locks; 1196 } 1197 1198 for (i = 0; i < dccp_hashinfo.bhash_size; i++) { 1199 spin_lock_init(&dccp_hashinfo.bhash[i].lock); 1200 INIT_HLIST_HEAD(&dccp_hashinfo.bhash[i].chain); 1201 } 1202 1203 rc = dccp_mib_init(); 1204 if (rc) 1205 goto out_free_dccp_bhash; 1206 1207 rc = dccp_ackvec_init(); 1208 if (rc) 1209 goto out_free_dccp_mib; 1210 1211 rc = dccp_sysctl_init(); 1212 if (rc) 1213 goto out_ackvec_exit; 1214 1215 rc = ccid_initialize_builtins(); 1216 if (rc) 1217 goto out_sysctl_exit; 1218 1219 dccp_timestamping_init(); 1220 1221 return 0; 1222 1223 out_sysctl_exit: 1224 dccp_sysctl_exit(); 1225 out_ackvec_exit: 1226 dccp_ackvec_exit(); 1227 out_free_dccp_mib: 1228 dccp_mib_exit(); 1229 out_free_dccp_bhash: 1230 free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order); 1231 out_free_dccp_locks: 1232 inet_ehash_locks_free(&dccp_hashinfo); 1233 out_free_dccp_ehash: 1234 free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order); 1235 out_free_bind_bucket_cachep: 1236 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep); 1237 out_free_percpu: 1238 percpu_counter_destroy(&dccp_orphan_count); 1239 out_fail: 1240 dccp_hashinfo.bhash = NULL; 1241 dccp_hashinfo.ehash = NULL; 1242 dccp_hashinfo.bind_bucket_cachep = NULL; 1243 return rc; 1244 } 1245 1246 static void __exit dccp_fini(void) 1247 { 1248 ccid_cleanup_builtins(); 1249 dccp_mib_exit(); 1250 free_pages((unsigned long)dccp_hashinfo.bhash, 1251 get_order(dccp_hashinfo.bhash_size * 1252 sizeof(struct inet_bind_hashbucket))); 1253 free_pages((unsigned long)dccp_hashinfo.ehash, 1254 get_order((dccp_hashinfo.ehash_mask + 1) * 1255 sizeof(struct inet_ehash_bucket))); 1256 inet_ehash_locks_free(&dccp_hashinfo); 1257 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep); 1258 dccp_ackvec_exit(); 1259 dccp_sysctl_exit(); 1260 percpu_counter_destroy(&dccp_orphan_count); 1261 } 1262 1263 module_init(dccp_init); 1264 module_exit(dccp_fini); 1265 1266 MODULE_LICENSE("GPL"); 1267 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>"); 1268 MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol"); 1269