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