pep.c revision 2ddc1ac1b9f00096869a48b97c28de72386200d2
1/* 2 * File: pep.c 3 * 4 * Phonet pipe protocol end point socket 5 * 6 * Copyright (C) 2008 Nokia Corporation. 7 * 8 * Author: Rémi Denis-Courmont <remi.denis-courmont@nokia.com> 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License 12 * version 2 as published by the Free Software Foundation. 13 * 14 * This program is distributed in the hope that it will be useful, but 15 * WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 22 * 02110-1301 USA 23 */ 24 25#include <linux/kernel.h> 26#include <linux/socket.h> 27#include <net/sock.h> 28#include <net/tcp_states.h> 29#include <asm/ioctls.h> 30 31#include <linux/phonet.h> 32#include <net/phonet/phonet.h> 33#include <net/phonet/pep.h> 34#include <net/phonet/gprs.h> 35 36/* sk_state values: 37 * TCP_CLOSE sock not in use yet 38 * TCP_CLOSE_WAIT disconnected pipe 39 * TCP_LISTEN listening pipe endpoint 40 * TCP_SYN_RECV connected pipe in disabled state 41 * TCP_ESTABLISHED connected pipe in enabled state 42 * 43 * pep_sock locking: 44 * - sk_state, ackq, hlist: sock lock needed 45 * - listener: read only 46 * - pipe_handle: read only 47 */ 48 49#define CREDITS_MAX 10 50#define CREDITS_THR 7 51 52static const struct sockaddr_pn pipe_srv = { 53 .spn_family = AF_PHONET, 54 .spn_resource = 0xD9, /* pipe service */ 55}; 56 57#define pep_sb_size(s) (((s) + 5) & ~3) /* 2-bytes head, 32-bits aligned */ 58 59/* Get the next TLV sub-block. */ 60static unsigned char *pep_get_sb(struct sk_buff *skb, u8 *ptype, u8 *plen, 61 void *buf) 62{ 63 void *data = NULL; 64 struct { 65 u8 sb_type; 66 u8 sb_len; 67 } *ph, h; 68 int buflen = *plen; 69 70 ph = skb_header_pointer(skb, 0, 2, &h); 71 if (ph == NULL || ph->sb_len < 2 || !pskb_may_pull(skb, ph->sb_len)) 72 return NULL; 73 ph->sb_len -= 2; 74 *ptype = ph->sb_type; 75 *plen = ph->sb_len; 76 77 if (buflen > ph->sb_len) 78 buflen = ph->sb_len; 79 data = skb_header_pointer(skb, 2, buflen, buf); 80 __skb_pull(skb, 2 + ph->sb_len); 81 return data; 82} 83 84static int pep_reply(struct sock *sk, struct sk_buff *oskb, 85 u8 code, const void *data, int len, gfp_t priority) 86{ 87 const struct pnpipehdr *oph = pnp_hdr(oskb); 88 struct pnpipehdr *ph; 89 struct sk_buff *skb; 90 91 skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority); 92 if (!skb) 93 return -ENOMEM; 94 skb_set_owner_w(skb, sk); 95 96 skb_reserve(skb, MAX_PNPIPE_HEADER); 97 __skb_put(skb, len); 98 skb_copy_to_linear_data(skb, data, len); 99 __skb_push(skb, sizeof(*ph)); 100 skb_reset_transport_header(skb); 101 ph = pnp_hdr(skb); 102 ph->utid = oph->utid; 103 ph->message_id = oph->message_id + 1; /* REQ -> RESP */ 104 ph->pipe_handle = oph->pipe_handle; 105 ph->error_code = code; 106 107 return pn_skb_send(sk, skb, &pipe_srv); 108} 109 110#define PAD 0x00 111static int pep_accept_conn(struct sock *sk, struct sk_buff *skb) 112{ 113 static const u8 data[20] = { 114 PAD, PAD, PAD, 2 /* sub-blocks */, 115 PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD, 116 PN_MULTI_CREDIT_FLOW_CONTROL, 117 PN_ONE_CREDIT_FLOW_CONTROL, 118 PN_LEGACY_FLOW_CONTROL, 119 PAD, 120 PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD, 121 PN_MULTI_CREDIT_FLOW_CONTROL, 122 PN_ONE_CREDIT_FLOW_CONTROL, 123 PN_LEGACY_FLOW_CONTROL, 124 PAD, 125 }; 126 127 might_sleep(); 128 return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data), 129 GFP_KERNEL); 130} 131 132static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code) 133{ 134 static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ }; 135 WARN_ON(code == PN_PIPE_NO_ERROR); 136 return pep_reply(sk, skb, code, data, sizeof(data), GFP_ATOMIC); 137} 138 139/* Control requests are not sent by the pipe service and have a specific 140 * message format. */ 141static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code, 142 gfp_t priority) 143{ 144 const struct pnpipehdr *oph = pnp_hdr(oskb); 145 struct sk_buff *skb; 146 struct pnpipehdr *ph; 147 struct sockaddr_pn dst; 148 149 skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority); 150 if (!skb) 151 return -ENOMEM; 152 skb_set_owner_w(skb, sk); 153 154 skb_reserve(skb, MAX_PHONET_HEADER); 155 ph = (struct pnpipehdr *)skb_put(skb, sizeof(*ph) + 4); 156 157 ph->utid = oph->utid; 158 ph->message_id = PNS_PEP_CTRL_RESP; 159 ph->pipe_handle = oph->pipe_handle; 160 ph->data[0] = oph->data[1]; /* CTRL id */ 161 ph->data[1] = oph->data[0]; /* PEP type */ 162 ph->data[2] = code; /* error code, at an usual offset */ 163 ph->data[3] = PAD; 164 ph->data[4] = PAD; 165 166 pn_skb_get_src_sockaddr(oskb, &dst); 167 return pn_skb_send(sk, skb, &dst); 168} 169 170static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority) 171{ 172 struct pep_sock *pn = pep_sk(sk); 173 struct pnpipehdr *ph; 174 struct sk_buff *skb; 175 176 skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority); 177 if (!skb) 178 return -ENOMEM; 179 skb_set_owner_w(skb, sk); 180 181 skb_reserve(skb, MAX_PNPIPE_HEADER + 4); 182 __skb_push(skb, sizeof(*ph) + 4); 183 skb_reset_transport_header(skb); 184 ph = pnp_hdr(skb); 185 ph->utid = 0; 186 ph->message_id = PNS_PEP_STATUS_IND; 187 ph->pipe_handle = pn->pipe_handle; 188 ph->pep_type = PN_PEP_TYPE_COMMON; 189 ph->data[1] = type; 190 ph->data[2] = PAD; 191 ph->data[3] = PAD; 192 ph->data[4] = status; 193 194 return pn_skb_send(sk, skb, &pipe_srv); 195} 196 197/* Send our RX flow control information to the sender. 198 * Socket must be locked. */ 199static void pipe_grant_credits(struct sock *sk) 200{ 201 struct pep_sock *pn = pep_sk(sk); 202 203 BUG_ON(sk->sk_state != TCP_ESTABLISHED); 204 205 switch (pn->rx_fc) { 206 case PN_LEGACY_FLOW_CONTROL: /* TODO */ 207 break; 208 case PN_ONE_CREDIT_FLOW_CONTROL: 209 pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL, 210 PEP_IND_READY, GFP_ATOMIC); 211 pn->rx_credits = 1; 212 break; 213 case PN_MULTI_CREDIT_FLOW_CONTROL: 214 if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX) 215 break; 216 if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS, 217 CREDITS_MAX - pn->rx_credits, 218 GFP_ATOMIC) == 0) 219 pn->rx_credits = CREDITS_MAX; 220 break; 221 } 222} 223 224static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb) 225{ 226 struct pep_sock *pn = pep_sk(sk); 227 struct pnpipehdr *hdr = pnp_hdr(skb); 228 int wake = 0; 229 230 if (!pskb_may_pull(skb, sizeof(*hdr) + 4)) 231 return -EINVAL; 232 233 if (hdr->data[0] != PN_PEP_TYPE_COMMON) { 234 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP type: %u\n", 235 (unsigned)hdr->data[0]); 236 return -EOPNOTSUPP; 237 } 238 239 switch (hdr->data[1]) { 240 case PN_PEP_IND_FLOW_CONTROL: 241 switch (pn->tx_fc) { 242 case PN_LEGACY_FLOW_CONTROL: 243 switch (hdr->data[4]) { 244 case PEP_IND_BUSY: 245 atomic_set(&pn->tx_credits, 0); 246 break; 247 case PEP_IND_READY: 248 atomic_set(&pn->tx_credits, wake = 1); 249 break; 250 } 251 break; 252 case PN_ONE_CREDIT_FLOW_CONTROL: 253 if (hdr->data[4] == PEP_IND_READY) 254 atomic_set(&pn->tx_credits, wake = 1); 255 break; 256 } 257 break; 258 259 case PN_PEP_IND_ID_MCFC_GRANT_CREDITS: 260 if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL) 261 break; 262 atomic_add(wake = hdr->data[4], &pn->tx_credits); 263 break; 264 265 default: 266 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP indication: %u\n", 267 (unsigned)hdr->data[1]); 268 return -EOPNOTSUPP; 269 } 270 if (wake) 271 sk->sk_write_space(sk); 272 return 0; 273} 274 275static int pipe_rcv_created(struct sock *sk, struct sk_buff *skb) 276{ 277 struct pep_sock *pn = pep_sk(sk); 278 struct pnpipehdr *hdr = pnp_hdr(skb); 279 u8 n_sb = hdr->data[0]; 280 281 pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL; 282 __skb_pull(skb, sizeof(*hdr)); 283 while (n_sb > 0) { 284 u8 type, buf[2], len = sizeof(buf); 285 u8 *data = pep_get_sb(skb, &type, &len, buf); 286 287 if (data == NULL) 288 return -EINVAL; 289 switch (type) { 290 case PN_PIPE_SB_NEGOTIATED_FC: 291 if (len < 2 || (data[0] | data[1]) > 3) 292 break; 293 pn->tx_fc = data[0] & 3; 294 pn->rx_fc = data[1] & 3; 295 break; 296 } 297 n_sb--; 298 } 299 return 0; 300} 301 302/* Queue an skb to a connected sock. 303 * Socket lock must be held. */ 304static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb) 305{ 306 struct pep_sock *pn = pep_sk(sk); 307 struct pnpipehdr *hdr = pnp_hdr(skb); 308 struct sk_buff_head *queue; 309 int err = 0; 310 311 BUG_ON(sk->sk_state == TCP_CLOSE_WAIT); 312 313 switch (hdr->message_id) { 314 case PNS_PEP_CONNECT_REQ: 315 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE); 316 break; 317 318 case PNS_PEP_DISCONNECT_REQ: 319 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); 320 sk->sk_state = TCP_CLOSE_WAIT; 321 if (!sock_flag(sk, SOCK_DEAD)) 322 sk->sk_state_change(sk); 323 break; 324 325 case PNS_PEP_ENABLE_REQ: 326 /* Wait for PNS_PIPE_(ENABLED|REDIRECTED)_IND */ 327 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); 328 break; 329 330 case PNS_PEP_RESET_REQ: 331 switch (hdr->state_after_reset) { 332 case PN_PIPE_DISABLE: 333 pn->init_enable = 0; 334 break; 335 case PN_PIPE_ENABLE: 336 pn->init_enable = 1; 337 break; 338 default: /* not allowed to send an error here!? */ 339 err = -EINVAL; 340 goto out; 341 } 342 /* fall through */ 343 case PNS_PEP_DISABLE_REQ: 344 atomic_set(&pn->tx_credits, 0); 345 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); 346 break; 347 348 case PNS_PEP_CTRL_REQ: 349 if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) 350 break; 351 __skb_pull(skb, 4); 352 queue = &pn->ctrlreq_queue; 353 goto queue; 354 355 case PNS_PIPE_DATA: 356 __skb_pull(skb, 3); /* Pipe data header */ 357 if (!pn_flow_safe(pn->rx_fc)) { 358 err = sock_queue_rcv_skb(sk, skb); 359 if (!err) 360 return 0; 361 break; 362 } 363 364 if (pn->rx_credits == 0) { 365 err = -ENOBUFS; 366 break; 367 } 368 pn->rx_credits--; 369 queue = &sk->sk_receive_queue; 370 goto queue; 371 372 case PNS_PEP_STATUS_IND: 373 pipe_rcv_status(sk, skb); 374 break; 375 376 case PNS_PIPE_REDIRECTED_IND: 377 err = pipe_rcv_created(sk, skb); 378 break; 379 380 case PNS_PIPE_CREATED_IND: 381 err = pipe_rcv_created(sk, skb); 382 if (err) 383 break; 384 /* fall through */ 385 case PNS_PIPE_RESET_IND: 386 if (!pn->init_enable) 387 break; 388 /* fall through */ 389 case PNS_PIPE_ENABLED_IND: 390 if (!pn_flow_safe(pn->tx_fc)) { 391 atomic_set(&pn->tx_credits, 1); 392 sk->sk_write_space(sk); 393 } 394 if (sk->sk_state == TCP_ESTABLISHED) 395 break; /* Nothing to do */ 396 sk->sk_state = TCP_ESTABLISHED; 397 pipe_grant_credits(sk); 398 break; 399 400 case PNS_PIPE_DISABLED_IND: 401 sk->sk_state = TCP_SYN_RECV; 402 pn->rx_credits = 0; 403 break; 404 405 default: 406 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP message: %u\n", 407 hdr->message_id); 408 err = -EINVAL; 409 } 410out: 411 kfree_skb(skb); 412 return err; 413 414queue: 415 skb->dev = NULL; 416 skb_set_owner_r(skb, sk); 417 err = skb->len; 418 skb_queue_tail(queue, skb); 419 if (!sock_flag(sk, SOCK_DEAD)) 420 sk->sk_data_ready(sk, err); 421 return 0; 422} 423 424/* Destroy connected sock. */ 425static void pipe_destruct(struct sock *sk) 426{ 427 struct pep_sock *pn = pep_sk(sk); 428 429 skb_queue_purge(&sk->sk_receive_queue); 430 skb_queue_purge(&pn->ctrlreq_queue); 431} 432 433static int pep_connreq_rcv(struct sock *sk, struct sk_buff *skb) 434{ 435 struct sock *newsk; 436 struct pep_sock *newpn, *pn = pep_sk(sk); 437 struct pnpipehdr *hdr; 438 struct sockaddr_pn dst; 439 u16 peer_type; 440 u8 pipe_handle, enabled, n_sb; 441 442 if (!pskb_pull(skb, sizeof(*hdr) + 4)) 443 return -EINVAL; 444 445 hdr = pnp_hdr(skb); 446 pipe_handle = hdr->pipe_handle; 447 switch (hdr->state_after_connect) { 448 case PN_PIPE_DISABLE: 449 enabled = 0; 450 break; 451 case PN_PIPE_ENABLE: 452 enabled = 1; 453 break; 454 default: 455 pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM); 456 return -EINVAL; 457 } 458 peer_type = hdr->other_pep_type << 8; 459 460 if (unlikely(sk->sk_state != TCP_LISTEN) || sk_acceptq_is_full(sk)) { 461 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE); 462 return -ENOBUFS; 463 } 464 465 /* Parse sub-blocks (options) */ 466 n_sb = hdr->data[4]; 467 while (n_sb > 0) { 468 u8 type, buf[1], len = sizeof(buf); 469 const u8 *data = pep_get_sb(skb, &type, &len, buf); 470 471 if (data == NULL) 472 return -EINVAL; 473 switch (type) { 474 case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE: 475 if (len < 1) 476 return -EINVAL; 477 peer_type = (peer_type & 0xff00) | data[0]; 478 break; 479 } 480 n_sb--; 481 } 482 483 skb = skb_clone(skb, GFP_ATOMIC); 484 if (!skb) 485 return -ENOMEM; 486 487 /* Create a new to-be-accepted sock */ 488 newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_ATOMIC, sk->sk_prot); 489 if (!newsk) { 490 kfree_skb(skb); 491 return -ENOMEM; 492 } 493 sock_init_data(NULL, newsk); 494 newsk->sk_state = TCP_SYN_RECV; 495 newsk->sk_backlog_rcv = pipe_do_rcv; 496 newsk->sk_protocol = sk->sk_protocol; 497 newsk->sk_destruct = pipe_destruct; 498 499 newpn = pep_sk(newsk); 500 pn_skb_get_dst_sockaddr(skb, &dst); 501 newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst); 502 newpn->pn_sk.resource = pn->pn_sk.resource; 503 skb_queue_head_init(&newpn->ctrlreq_queue); 504 newpn->pipe_handle = pipe_handle; 505 atomic_set(&newpn->tx_credits, 0); 506 newpn->peer_type = peer_type; 507 newpn->rx_credits = 0; 508 newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL; 509 newpn->init_enable = enabled; 510 511 BUG_ON(!skb_queue_empty(&newsk->sk_receive_queue)); 512 skb_queue_head(&newsk->sk_receive_queue, skb); 513 if (!sock_flag(sk, SOCK_DEAD)) 514 sk->sk_data_ready(sk, 0); 515 516 sk_acceptq_added(sk); 517 sk_add_node(newsk, &pn->ackq); 518 return 0; 519} 520 521/* Listening sock must be locked */ 522static struct sock *pep_find_pipe(const struct hlist_head *hlist, 523 const struct sockaddr_pn *dst, 524 u8 pipe_handle) 525{ 526 struct hlist_node *node; 527 struct sock *sknode; 528 u16 dobj = pn_sockaddr_get_object(dst); 529 530 sk_for_each(sknode, node, hlist) { 531 struct pep_sock *pnnode = pep_sk(sknode); 532 533 /* Ports match, but addresses might not: */ 534 if (pnnode->pn_sk.sobject != dobj) 535 continue; 536 if (pnnode->pipe_handle != pipe_handle) 537 continue; 538 if (sknode->sk_state == TCP_CLOSE_WAIT) 539 continue; 540 541 sock_hold(sknode); 542 return sknode; 543 } 544 return NULL; 545} 546 547/* 548 * Deliver an skb to a listening sock. 549 * Socket lock must be held. 550 * We then queue the skb to the right connected sock (if any). 551 */ 552static int pep_do_rcv(struct sock *sk, struct sk_buff *skb) 553{ 554 struct pep_sock *pn = pep_sk(sk); 555 struct sock *sknode; 556 struct pnpipehdr *hdr; 557 struct sockaddr_pn dst; 558 int err = NET_RX_SUCCESS; 559 u8 pipe_handle; 560 561 if (!pskb_may_pull(skb, sizeof(*hdr))) 562 goto drop; 563 564 hdr = pnp_hdr(skb); 565 pipe_handle = hdr->pipe_handle; 566 if (pipe_handle == PN_PIPE_INVALID_HANDLE) 567 goto drop; 568 569 pn_skb_get_dst_sockaddr(skb, &dst); 570 571 /* Look for an existing pipe handle */ 572 sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle); 573 if (sknode) 574 return sk_receive_skb(sknode, skb, 1); 575 576 /* Look for a pipe handle pending accept */ 577 sknode = pep_find_pipe(&pn->ackq, &dst, pipe_handle); 578 if (sknode) { 579 sock_put(sknode); 580 if (net_ratelimit()) 581 printk(KERN_WARNING"Phonet unconnected PEP ignored"); 582 err = NET_RX_DROP; 583 goto drop; 584 } 585 586 switch (hdr->message_id) { 587 case PNS_PEP_CONNECT_REQ: 588 err = pep_connreq_rcv(sk, skb); 589 break; 590 591 case PNS_PEP_DISCONNECT_REQ: 592 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); 593 break; 594 595 case PNS_PEP_CTRL_REQ: 596 pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC); 597 break; 598 599 case PNS_PEP_RESET_REQ: 600 case PNS_PEP_ENABLE_REQ: 601 case PNS_PEP_DISABLE_REQ: 602 /* invalid handle is not even allowed here! */ 603 default: 604 err = NET_RX_DROP; 605 } 606drop: 607 kfree_skb(skb); 608 return err; 609} 610 611/* associated socket ceases to exist */ 612static void pep_sock_close(struct sock *sk, long timeout) 613{ 614 struct pep_sock *pn = pep_sk(sk); 615 int ifindex = 0; 616 617 sk_common_release(sk); 618 619 lock_sock(sk); 620 if (sk->sk_state == TCP_LISTEN) { 621 /* Destroy the listen queue */ 622 struct sock *sknode; 623 struct hlist_node *p, *n; 624 625 sk_for_each_safe(sknode, p, n, &pn->ackq) 626 sk_del_node_init(sknode); 627 sk->sk_state = TCP_CLOSE; 628 } 629 ifindex = pn->ifindex; 630 pn->ifindex = 0; 631 release_sock(sk); 632 633 if (ifindex) 634 gprs_detach(sk); 635} 636 637static int pep_wait_connreq(struct sock *sk, int noblock) 638{ 639 struct task_struct *tsk = current; 640 struct pep_sock *pn = pep_sk(sk); 641 long timeo = sock_rcvtimeo(sk, noblock); 642 643 for (;;) { 644 DEFINE_WAIT(wait); 645 646 if (sk->sk_state != TCP_LISTEN) 647 return -EINVAL; 648 if (!hlist_empty(&pn->ackq)) 649 break; 650 if (!timeo) 651 return -EWOULDBLOCK; 652 if (signal_pending(tsk)) 653 return sock_intr_errno(timeo); 654 655 prepare_to_wait_exclusive(&sk->sk_socket->wait, &wait, 656 TASK_INTERRUPTIBLE); 657 release_sock(sk); 658 timeo = schedule_timeout(timeo); 659 lock_sock(sk); 660 finish_wait(&sk->sk_socket->wait, &wait); 661 } 662 663 return 0; 664} 665 666static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp) 667{ 668 struct pep_sock *pn = pep_sk(sk); 669 struct sock *newsk = NULL; 670 struct sk_buff *oskb; 671 int err; 672 673 lock_sock(sk); 674 err = pep_wait_connreq(sk, flags & O_NONBLOCK); 675 if (err) 676 goto out; 677 678 newsk = __sk_head(&pn->ackq); 679 680 oskb = skb_dequeue(&newsk->sk_receive_queue); 681 err = pep_accept_conn(newsk, oskb); 682 if (err) { 683 skb_queue_head(&newsk->sk_receive_queue, oskb); 684 newsk = NULL; 685 goto out; 686 } 687 688 sock_hold(sk); 689 pep_sk(newsk)->listener = sk; 690 691 sock_hold(newsk); 692 sk_del_node_init(newsk); 693 sk_acceptq_removed(sk); 694 sk_add_node(newsk, &pn->hlist); 695 __sock_put(newsk); 696 697out: 698 release_sock(sk); 699 *errp = err; 700 return newsk; 701} 702 703static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg) 704{ 705 struct pep_sock *pn = pep_sk(sk); 706 int answ; 707 708 switch (cmd) { 709 case SIOCINQ: 710 if (sk->sk_state == TCP_LISTEN) 711 return -EINVAL; 712 713 lock_sock(sk); 714 if (sock_flag(sk, SOCK_URGINLINE) 715 && !skb_queue_empty(&pn->ctrlreq_queue)) 716 answ = skb_peek(&pn->ctrlreq_queue)->len; 717 else if (!skb_queue_empty(&sk->sk_receive_queue)) 718 answ = skb_peek(&sk->sk_receive_queue)->len; 719 else 720 answ = 0; 721 release_sock(sk); 722 return put_user(answ, (int __user *)arg); 723 } 724 725 return -ENOIOCTLCMD; 726} 727 728static int pep_init(struct sock *sk) 729{ 730 struct pep_sock *pn = pep_sk(sk); 731 732 INIT_HLIST_HEAD(&pn->ackq); 733 INIT_HLIST_HEAD(&pn->hlist); 734 skb_queue_head_init(&pn->ctrlreq_queue); 735 pn->pipe_handle = PN_PIPE_INVALID_HANDLE; 736 return 0; 737} 738 739static int pep_setsockopt(struct sock *sk, int level, int optname, 740 char __user *optval, int optlen) 741{ 742 struct pep_sock *pn = pep_sk(sk); 743 int val = 0, err = 0; 744 745 if (level != SOL_PNPIPE) 746 return -ENOPROTOOPT; 747 if (optlen >= sizeof(int)) { 748 if (get_user(val, (int __user *) optval)) 749 return -EFAULT; 750 } 751 752 lock_sock(sk); 753 switch (optname) { 754 case PNPIPE_ENCAP: 755 if (val && val != PNPIPE_ENCAP_IP) { 756 err = -EINVAL; 757 break; 758 } 759 if (!pn->ifindex == !val) 760 break; /* Nothing to do! */ 761 if (!capable(CAP_NET_ADMIN)) { 762 err = -EPERM; 763 break; 764 } 765 if (val) { 766 release_sock(sk); 767 err = gprs_attach(sk); 768 if (err > 0) { 769 pn->ifindex = err; 770 err = 0; 771 } 772 } else { 773 pn->ifindex = 0; 774 release_sock(sk); 775 gprs_detach(sk); 776 err = 0; 777 } 778 goto out_norel; 779 default: 780 err = -ENOPROTOOPT; 781 } 782 release_sock(sk); 783 784out_norel: 785 return err; 786} 787 788static int pep_getsockopt(struct sock *sk, int level, int optname, 789 char __user *optval, int __user *optlen) 790{ 791 struct pep_sock *pn = pep_sk(sk); 792 int len, val; 793 794 if (level != SOL_PNPIPE) 795 return -ENOPROTOOPT; 796 if (get_user(len, optlen)) 797 return -EFAULT; 798 799 switch (optname) { 800 case PNPIPE_ENCAP: 801 val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE; 802 break; 803 case PNPIPE_IFINDEX: 804 val = pn->ifindex; 805 break; 806 default: 807 return -ENOPROTOOPT; 808 } 809 810 len = min_t(unsigned int, sizeof(int), len); 811 if (put_user(len, optlen)) 812 return -EFAULT; 813 if (put_user(val, (int __user *) optval)) 814 return -EFAULT; 815 return 0; 816} 817 818static int pipe_skb_send(struct sock *sk, struct sk_buff *skb) 819{ 820 struct pep_sock *pn = pep_sk(sk); 821 struct pnpipehdr *ph; 822 823 if (pn_flow_safe(pn->tx_fc) && 824 !atomic_add_unless(&pn->tx_credits, -1, 0)) { 825 kfree_skb(skb); 826 return -ENOBUFS; 827 } 828 829 skb_push(skb, 3); 830 skb_reset_transport_header(skb); 831 ph = pnp_hdr(skb); 832 ph->utid = 0; 833 ph->message_id = PNS_PIPE_DATA; 834 ph->pipe_handle = pn->pipe_handle; 835 836 return pn_skb_send(sk, skb, &pipe_srv); 837} 838 839static int pep_sendmsg(struct kiocb *iocb, struct sock *sk, 840 struct msghdr *msg, size_t len) 841{ 842 struct pep_sock *pn = pep_sk(sk); 843 struct sk_buff *skb = NULL; 844 long timeo; 845 int flags = msg->msg_flags; 846 int err, done; 847 848 if (msg->msg_flags & MSG_OOB || !(msg->msg_flags & MSG_EOR)) 849 return -EOPNOTSUPP; 850 851 lock_sock(sk); 852 timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); 853 if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) { 854 err = -ENOTCONN; 855 goto out; 856 } 857 if (sk->sk_state != TCP_ESTABLISHED) { 858 /* Wait until the pipe gets to enabled state */ 859disabled: 860 err = sk_stream_wait_connect(sk, &timeo); 861 if (err) 862 goto out; 863 864 if (sk->sk_state == TCP_CLOSE_WAIT) { 865 err = -ECONNRESET; 866 goto out; 867 } 868 } 869 BUG_ON(sk->sk_state != TCP_ESTABLISHED); 870 871 /* Wait until flow control allows TX */ 872 done = atomic_read(&pn->tx_credits); 873 while (!done) { 874 DEFINE_WAIT(wait); 875 876 if (!timeo) { 877 err = -EAGAIN; 878 goto out; 879 } 880 if (signal_pending(current)) { 881 err = sock_intr_errno(timeo); 882 goto out; 883 } 884 885 prepare_to_wait(&sk->sk_socket->wait, &wait, 886 TASK_INTERRUPTIBLE); 887 done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits)); 888 finish_wait(&sk->sk_socket->wait, &wait); 889 890 if (sk->sk_state != TCP_ESTABLISHED) 891 goto disabled; 892 } 893 894 if (!skb) { 895 skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len, 896 flags & MSG_DONTWAIT, &err); 897 if (skb == NULL) 898 goto out; 899 skb_reserve(skb, MAX_PHONET_HEADER + 3); 900 901 if (sk->sk_state != TCP_ESTABLISHED || 902 !atomic_read(&pn->tx_credits)) 903 goto disabled; /* sock_alloc_send_skb might sleep */ 904 } 905 906 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); 907 if (err < 0) 908 goto out; 909 910 err = pipe_skb_send(sk, skb); 911 if (err >= 0) 912 err = len; /* success! */ 913 skb = NULL; 914out: 915 release_sock(sk); 916 kfree_skb(skb); 917 return err; 918} 919 920int pep_writeable(struct sock *sk) 921{ 922 struct pep_sock *pn = pep_sk(sk); 923 924 return atomic_read(&pn->tx_credits); 925} 926 927int pep_write(struct sock *sk, struct sk_buff *skb) 928{ 929 struct sk_buff *rskb, *fs; 930 int flen = 0; 931 932 rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC); 933 if (!rskb) { 934 kfree_skb(skb); 935 return -ENOMEM; 936 } 937 skb_shinfo(rskb)->frag_list = skb; 938 rskb->len += skb->len; 939 rskb->data_len += rskb->len; 940 rskb->truesize += rskb->len; 941 942 /* Avoid nested fragments */ 943 for (fs = skb_shinfo(skb)->frag_list; fs; fs = fs->next) 944 flen += fs->len; 945 skb->next = skb_shinfo(skb)->frag_list; 946 skb_shinfo(skb)->frag_list = NULL; 947 skb->len -= flen; 948 skb->data_len -= flen; 949 skb->truesize -= flen; 950 951 skb_reserve(rskb, MAX_PHONET_HEADER + 3); 952 return pipe_skb_send(sk, rskb); 953} 954 955struct sk_buff *pep_read(struct sock *sk) 956{ 957 struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue); 958 959 if (sk->sk_state == TCP_ESTABLISHED) 960 pipe_grant_credits(sk); 961 return skb; 962} 963 964static int pep_recvmsg(struct kiocb *iocb, struct sock *sk, 965 struct msghdr *msg, size_t len, int noblock, 966 int flags, int *addr_len) 967{ 968 struct sk_buff *skb; 969 int err; 970 971 if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE))) 972 return -ENOTCONN; 973 974 if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) { 975 /* Dequeue and acknowledge control request */ 976 struct pep_sock *pn = pep_sk(sk); 977 978 skb = skb_dequeue(&pn->ctrlreq_queue); 979 if (skb) { 980 pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR, 981 GFP_KERNEL); 982 msg->msg_flags |= MSG_OOB; 983 goto copy; 984 } 985 if (flags & MSG_OOB) 986 return -EINVAL; 987 } 988 989 skb = skb_recv_datagram(sk, flags, noblock, &err); 990 lock_sock(sk); 991 if (skb == NULL) { 992 if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT) 993 err = -ECONNRESET; 994 release_sock(sk); 995 return err; 996 } 997 998 if (sk->sk_state == TCP_ESTABLISHED) 999 pipe_grant_credits(sk); 1000 release_sock(sk); 1001copy: 1002 msg->msg_flags |= MSG_EOR; 1003 if (skb->len > len) 1004 msg->msg_flags |= MSG_TRUNC; 1005 else 1006 len = skb->len; 1007 1008 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len); 1009 if (!err) 1010 err = (flags & MSG_TRUNC) ? skb->len : len; 1011 1012 skb_free_datagram(sk, skb); 1013 return err; 1014} 1015 1016static void pep_sock_unhash(struct sock *sk) 1017{ 1018 struct pep_sock *pn = pep_sk(sk); 1019 struct sock *skparent = NULL; 1020 1021 lock_sock(sk); 1022 if ((1 << sk->sk_state) & ~(TCPF_CLOSE|TCPF_LISTEN)) { 1023 skparent = pn->listener; 1024 sk_del_node_init(sk); 1025 release_sock(sk); 1026 1027 sk = skparent; 1028 pn = pep_sk(skparent); 1029 lock_sock(sk); 1030 } 1031 /* Unhash a listening sock only when it is closed 1032 * and all of its active connected pipes are closed. */ 1033 if (hlist_empty(&pn->hlist)) 1034 pn_sock_unhash(&pn->pn_sk.sk); 1035 release_sock(sk); 1036 1037 if (skparent) 1038 sock_put(skparent); 1039} 1040 1041static struct proto pep_proto = { 1042 .close = pep_sock_close, 1043 .accept = pep_sock_accept, 1044 .ioctl = pep_ioctl, 1045 .init = pep_init, 1046 .setsockopt = pep_setsockopt, 1047 .getsockopt = pep_getsockopt, 1048 .sendmsg = pep_sendmsg, 1049 .recvmsg = pep_recvmsg, 1050 .backlog_rcv = pep_do_rcv, 1051 .hash = pn_sock_hash, 1052 .unhash = pep_sock_unhash, 1053 .get_port = pn_sock_get_port, 1054 .obj_size = sizeof(struct pep_sock), 1055 .owner = THIS_MODULE, 1056 .name = "PNPIPE", 1057}; 1058 1059static struct phonet_protocol pep_pn_proto = { 1060 .ops = &phonet_stream_ops, 1061 .prot = &pep_proto, 1062 .sock_type = SOCK_SEQPACKET, 1063}; 1064 1065static int __init pep_register(void) 1066{ 1067 return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto); 1068} 1069 1070static void __exit pep_unregister(void) 1071{ 1072 phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto); 1073} 1074 1075module_init(pep_register); 1076module_exit(pep_unregister); 1077MODULE_AUTHOR("Remi Denis-Courmont, Nokia"); 1078MODULE_DESCRIPTION("Phonet pipe protocol"); 1079MODULE_LICENSE("GPL"); 1080MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE); 1081