net/phonet/pep.c

   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
   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/slab.h>
  27 #include <linux/socket.h>
  28 #include <net/sock.h>
  29 #include <net/tcp_states.h>
  30 #include <asm/ioctls.h>
  31
  32 #include <linux/phonet.h>
  33 #include <linux/module.h>
  34 #include <net/phonet/phonet.h>
  35 #include <net/phonet/pep.h>
  36 #include <net/phonet/gprs.h>
  37
  38 /* sk_state values:
  39  * TCP_CLOSE            sock not in use yet
  40  * TCP_CLOSE_WAIT       disconnected pipe
  41  * TCP_LISTEN           listening pipe endpoint
  42  * TCP_SYN_RECV         connected pipe in disabled state
  43  * TCP_ESTABLISHED      connected pipe in enabled state
  44  *
  45  * pep_sock locking:
  46  *  - sk_state, hlist: sock lock needed
  47  *  - listener: read only
  48  *  - pipe_handle: read only
  49  */
  50
  51 #define CREDITS_MAX     10
  52 #define CREDITS_THR     7
  53
  54 #define pep_sb_size(s) (((s) + 5) & ~3) /* 2-bytes head, 32-bits aligned */
  55
  56 /* Get the next TLV sub-block. */
  57 static unsigned char *pep_get_sb(struct sk_buff *skb, u8 *ptype, u8 *plen,
  58                                         void *buf)
  59 {
  60         void *data = NULL;
  61         struct {
  62                 u8 sb_type;
  63                 u8 sb_len;
  64         } *ph, h;
  65         int buflen = *plen;
  66
  67         ph = skb_header_pointer(skb, 0, 2, &h);
  68         if (ph == NULL || ph->sb_len < 2 || !pskb_may_pull(skb, ph->sb_len))
  69                 return NULL;
  70         ph->sb_len -= 2;
  71         *ptype = ph->sb_type;
  72         *plen = ph->sb_len;
  73
  74         if (buflen > ph->sb_len)
  75                 buflen = ph->sb_len;
  76         data = skb_header_pointer(skb, 2, buflen, buf);
  77         __skb_pull(skb, 2 + ph->sb_len);
  78         return data;
  79 }
  80
  81 static struct sk_buff *pep_alloc_skb(struct sock *sk, const void *payload,
  82                                         int len, gfp_t priority)
  83 {
  84         struct sk_buff *skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority);
  85         if (!skb)
  86                 return NULL;
  87         skb_set_owner_w(skb, sk);
  88
  89         skb_reserve(skb, MAX_PNPIPE_HEADER);
  90         __skb_put(skb, len);
  91         skb_copy_to_linear_data(skb, payload, len);
  92         __skb_push(skb, sizeof(struct pnpipehdr));
  93         skb_reset_transport_header(skb);
  94         return skb;
  95 }
  96
  97 static int pep_reply(struct sock *sk, struct sk_buff *oskb, u8 code,
  98                         const void *data, int len, gfp_t priority)
  99 {
 100         const struct pnpipehdr *oph = pnp_hdr(oskb);
 101         struct pnpipehdr *ph;
 102         struct sk_buff *skb;
 103         struct sockaddr_pn peer;
 104
 105         skb = pep_alloc_skb(sk, data, len, priority);
 106         if (!skb)
 107                 return -ENOMEM;
 108
 109         ph = pnp_hdr(skb);
 110         ph->utid = oph->utid;
 111         ph->message_id = oph->message_id + 1; /* REQ -> RESP */
 112         ph->pipe_handle = oph->pipe_handle;
 113         ph->error_code = code;
 114
 115         pn_skb_get_src_sockaddr(oskb, &peer);
 116         return pn_skb_send(sk, skb, &peer);
 117 }
 118
 119 static int pep_indicate(struct sock *sk, u8 id, u8 code,
 120                         const void *data, int len, gfp_t priority)
 121 {
 122         struct pep_sock *pn = pep_sk(sk);
 123         struct pnpipehdr *ph;
 124         struct sk_buff *skb;
 125
 126         skb = pep_alloc_skb(sk, data, len, priority);
 127         if (!skb)
 128                 return -ENOMEM;
 129
 130         ph = pnp_hdr(skb);
 131         ph->utid = 0;
 132         ph->message_id = id;
 133         ph->pipe_handle = pn->pipe_handle;
 134         ph->data[0] = code;
 135         return pn_skb_send(sk, skb, NULL);
 136 }
 137
 138 #define PAD 0x00
 139
 140 static int pipe_handler_request(struct sock *sk, u8 id, u8 code,
 141                                 const void *data, int len)
 142 {
 143         struct pep_sock *pn = pep_sk(sk);
 144         struct pnpipehdr *ph;
 145         struct sk_buff *skb;
 146
 147         skb = pep_alloc_skb(sk, data, len, GFP_KERNEL);
 148         if (!skb)
 149                 return -ENOMEM;
 150
 151         ph = pnp_hdr(skb);
 152         ph->utid = id; /* whatever */
 153         ph->message_id = id;
 154         ph->pipe_handle = pn->pipe_handle;
 155         ph->data[0] = code;
 156         return pn_skb_send(sk, skb, NULL);
 157 }
 158
 159 static int pipe_handler_send_created_ind(struct sock *sk)
 160 {
 161         struct pep_sock *pn = pep_sk(sk);
 162         u8 data[4] = {
 163                 PN_PIPE_SB_NEGOTIATED_FC, pep_sb_size(2),
 164                 pn->tx_fc, pn->rx_fc,
 165         };
 166
 167         return pep_indicate(sk, PNS_PIPE_CREATED_IND, 1 /* sub-blocks */,
 168                                 data, 4, GFP_ATOMIC);
 169 }
 170
 171 static int pep_accept_conn(struct sock *sk, struct sk_buff *skb)
 172 {
 173         static const u8 data[20] = {
 174                 PAD, PAD, PAD, 2 /* sub-blocks */,
 175                 PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD,
 176                         PN_MULTI_CREDIT_FLOW_CONTROL,
 177                         PN_ONE_CREDIT_FLOW_CONTROL,
 178                         PN_LEGACY_FLOW_CONTROL,
 179                         PAD,
 180                 PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD,
 181                         PN_MULTI_CREDIT_FLOW_CONTROL,
 182                         PN_ONE_CREDIT_FLOW_CONTROL,
 183                         PN_LEGACY_FLOW_CONTROL,
 184                         PAD,
 185         };
 186
 187         might_sleep();
 188         return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data),
 189                                 GFP_KERNEL);
 190 }
 191
 192 static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code,
 193                                 gfp_t priority)
 194 {
 195         static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ };
 196         WARN_ON(code == PN_PIPE_NO_ERROR);
 197         return pep_reply(sk, skb, code, data, sizeof(data), priority);
 198 }
 199
 200 /* Control requests are not sent by the pipe service and have a specific
 201  * message format. */
 202 static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code,
 203                                 gfp_t priority)
 204 {
 205         const struct pnpipehdr *oph = pnp_hdr(oskb);
 206         struct sk_buff *skb;
 207         struct pnpipehdr *ph;
 208         struct sockaddr_pn dst;
 209         u8 data[4] = {
 210                 oph->data[0], /* PEP type */
 211                 code, /* error code, at an unusual offset */
 212                 PAD, PAD,
 213         };
 214
 215         skb = pep_alloc_skb(sk, data, 4, priority);
 216         if (!skb)
 217                 return -ENOMEM;
 218
 219         ph = pnp_hdr(skb);
 220         ph->utid = oph->utid;
 221         ph->message_id = PNS_PEP_CTRL_RESP;
 222         ph->pipe_handle = oph->pipe_handle;
 223         ph->data[0] = oph->data[1]; /* CTRL id */
 224
 225         pn_skb_get_src_sockaddr(oskb, &dst);
 226         return pn_skb_send(sk, skb, &dst);
 227 }
 228
 229 static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority)
 230 {
 231         u8 data[4] = { type, PAD, PAD, status };
 232
 233         return pep_indicate(sk, PNS_PEP_STATUS_IND, PN_PEP_TYPE_COMMON,
 234                                 data, 4, priority);
 235 }
 236
 237 /* Send our RX flow control information to the sender.
 238  * Socket must be locked. */
 239 static void pipe_grant_credits(struct sock *sk, gfp_t priority)
 240 {
 241         struct pep_sock *pn = pep_sk(sk);
 242
 243         BUG_ON(sk->sk_state != TCP_ESTABLISHED);
 244
 245         switch (pn->rx_fc) {
 246         case PN_LEGACY_FLOW_CONTROL: /* TODO */
 247                 break;
 248         case PN_ONE_CREDIT_FLOW_CONTROL:
 249                 if (pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL,
 250                                         PEP_IND_READY, priority) == 0)
 251                         pn->rx_credits = 1;
 252                 break;
 253         case PN_MULTI_CREDIT_FLOW_CONTROL:
 254                 if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX)
 255                         break;
 256                 if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS,
 257                                         CREDITS_MAX - pn->rx_credits,
 258                                         priority) == 0)
 259                         pn->rx_credits = CREDITS_MAX;
 260                 break;
 261         }
 262 }
 263
 264 static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb)
 265 {
 266         struct pep_sock *pn = pep_sk(sk);
 267         struct pnpipehdr *hdr;
 268         int wake = 0;
 269
 270         if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
 271                 return -EINVAL;
 272
 273         hdr = pnp_hdr(skb);
 274         if (hdr->data[0] != PN_PEP_TYPE_COMMON) {
 275                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP type: %u\n",
 276                                 (unsigned int)hdr->data[0]);
 277                 return -EOPNOTSUPP;
 278         }
 279
 280         switch (hdr->data[1]) {
 281         case PN_PEP_IND_FLOW_CONTROL:
 282                 switch (pn->tx_fc) {
 283                 case PN_LEGACY_FLOW_CONTROL:
 284                         switch (hdr->data[4]) {
 285                         case PEP_IND_BUSY:
 286                                 atomic_set(&pn->tx_credits, 0);
 287                                 break;
 288                         case PEP_IND_READY:
 289                                 atomic_set(&pn->tx_credits, wake = 1);
 290                                 break;
 291                         }
 292                         break;
 293                 case PN_ONE_CREDIT_FLOW_CONTROL:
 294                         if (hdr->data[4] == PEP_IND_READY)
 295                                 atomic_set(&pn->tx_credits, wake = 1);
 296                         break;
 297                 }
 298                 break;
 299
 300         case PN_PEP_IND_ID_MCFC_GRANT_CREDITS:
 301                 if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL)
 302                         break;
 303                 atomic_add(wake = hdr->data[4], &pn->tx_credits);
 304                 break;
 305
 306         default:
 307                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP indication: %u\n",
 308                                 (unsigned int)hdr->data[1]);
 309                 return -EOPNOTSUPP;
 310         }
 311         if (wake)
 312                 sk->sk_write_space(sk);
 313         return 0;
 314 }
 315
 316 static int pipe_rcv_created(struct sock *sk, struct sk_buff *skb)
 317 {
 318         struct pep_sock *pn = pep_sk(sk);
 319         struct pnpipehdr *hdr = pnp_hdr(skb);
 320         u8 n_sb = hdr->data[0];
 321
 322         pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
 323         __skb_pull(skb, sizeof(*hdr));
 324         while (n_sb > 0) {
 325                 u8 type, buf[2], len = sizeof(buf);
 326                 u8 *data = pep_get_sb(skb, &type, &len, buf);
 327
 328                 if (data == NULL)
 329                         return -EINVAL;
 330                 switch (type) {
 331                 case PN_PIPE_SB_NEGOTIATED_FC:
 332                         if (len < 2 || (data[0] | data[1]) > 3)
 333                                 break;
 334                         pn->tx_fc = data[0] & 3;
 335                         pn->rx_fc = data[1] & 3;
 336                         break;
 337                 }
 338                 n_sb--;
 339         }
 340         return 0;
 341 }
 342
 343 /* Queue an skb to a connected sock.
 344  * Socket lock must be held. */
 345 static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
 346 {
 347         struct pep_sock *pn = pep_sk(sk);
 348         struct pnpipehdr *hdr = pnp_hdr(skb);
 349         struct sk_buff_head *queue;
 350         int err = 0;
 351
 352         BUG_ON(sk->sk_state == TCP_CLOSE_WAIT);
 353
 354         switch (hdr->message_id) {
 355         case PNS_PEP_CONNECT_REQ:
 356                 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_ATOMIC);
 357                 break;
 358
 359         case PNS_PEP_DISCONNECT_REQ:
 360                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 361                 sk->sk_state = TCP_CLOSE_WAIT;
 362                 if (!sock_flag(sk, SOCK_DEAD))
 363                         sk->sk_state_change(sk);
 364                 break;
 365
 366         case PNS_PEP_ENABLE_REQ:
 367                 /* Wait for PNS_PIPE_(ENABLED|REDIRECTED)_IND */
 368                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 369                 break;
 370
 371         case PNS_PEP_RESET_REQ:
 372                 switch (hdr->state_after_reset) {
 373                 case PN_PIPE_DISABLE:
 374                         pn->init_enable = 0;
 375                         break;
 376                 case PN_PIPE_ENABLE:
 377                         pn->init_enable = 1;
 378                         break;
 379                 default: /* not allowed to send an error here!? */
 380                         err = -EINVAL;
 381                         goto out;
 382                 }
 383                 /* fall through */
 384         case PNS_PEP_DISABLE_REQ:
 385                 atomic_set(&pn->tx_credits, 0);
 386                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 387                 break;
 388
 389         case PNS_PEP_CTRL_REQ:
 390                 if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) {
 391                         atomic_inc(&sk->sk_drops);
 392                         break;
 393                 }
 394                 __skb_pull(skb, 4);
 395                 queue = &pn->ctrlreq_queue;
 396                 goto queue;
 397
 398         case PNS_PIPE_ALIGNED_DATA:
 399                 __skb_pull(skb, 1);
 400                 /* fall through */
 401         case PNS_PIPE_DATA:
 402                 __skb_pull(skb, 3); /* Pipe data header */
 403                 if (!pn_flow_safe(pn->rx_fc)) {
 404                         err = sock_queue_rcv_skb(sk, skb);
 405                         if (!err)
 406                                 return NET_RX_SUCCESS;
 407                         err = -ENOBUFS;
 408                         break;
 409                 }
 410
 411                 if (pn->rx_credits == 0) {
 412                         atomic_inc(&sk->sk_drops);
 413                         err = -ENOBUFS;
 414                         break;
 415                 }
 416                 pn->rx_credits--;
 417                 queue = &sk->sk_receive_queue;
 418                 goto queue;
 419
 420         case PNS_PEP_STATUS_IND:
 421                 pipe_rcv_status(sk, skb);
 422                 break;
 423
 424         case PNS_PIPE_REDIRECTED_IND:
 425                 err = pipe_rcv_created(sk, skb);
 426                 break;
 427
 428         case PNS_PIPE_CREATED_IND:
 429                 err = pipe_rcv_created(sk, skb);
 430                 if (err)
 431                         break;
 432                 /* fall through */
 433         case PNS_PIPE_RESET_IND:
 434                 if (!pn->init_enable)
 435                         break;
 436                 /* fall through */
 437         case PNS_PIPE_ENABLED_IND:
 438                 if (!pn_flow_safe(pn->tx_fc)) {
 439                         atomic_set(&pn->tx_credits, 1);
 440                         sk->sk_write_space(sk);
 441                 }
 442                 if (sk->sk_state == TCP_ESTABLISHED)
 443                         break; /* Nothing to do */
 444                 sk->sk_state = TCP_ESTABLISHED;
 445                 pipe_grant_credits(sk, GFP_ATOMIC);
 446                 break;
 447
 448         case PNS_PIPE_DISABLED_IND:
 449                 sk->sk_state = TCP_SYN_RECV;
 450                 pn->rx_credits = 0;
 451                 break;
 452
 453         default:
 454                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP message: %u\n",
 455                                 hdr->message_id);
 456                 err = -EINVAL;
 457         }
 458 out:
 459         kfree_skb(skb);
 460         return (err == -ENOBUFS) ? NET_RX_DROP : NET_RX_SUCCESS;
 461
 462 queue:
 463         skb->dev = NULL;
 464         skb_set_owner_r(skb, sk);
 465         err = skb->len;
 466         skb_queue_tail(queue, skb);
 467         if (!sock_flag(sk, SOCK_DEAD))
 468                 sk->sk_data_ready(sk, err);
 469         return NET_RX_SUCCESS;
 470 }
 471
 472 /* Destroy connected sock. */
 473 static void pipe_destruct(struct sock *sk)
 474 {
 475         struct pep_sock *pn = pep_sk(sk);
 476
 477         skb_queue_purge(&sk->sk_receive_queue);
 478         skb_queue_purge(&pn->ctrlreq_queue);
 479 }
 480
 481 static u8 pipe_negotiate_fc(const u8 *fcs, unsigned int n)
 482 {
 483         unsigned int i;
 484         u8 final_fc = PN_NO_FLOW_CONTROL;
 485
 486         for (i = 0; i < n; i++) {
 487                 u8 fc = fcs[i];
 488
 489                 if (fc > final_fc && fc < PN_MAX_FLOW_CONTROL)
 490                         final_fc = fc;
 491         }
 492         return final_fc;
 493 }
 494
 495 static int pep_connresp_rcv(struct sock *sk, struct sk_buff *skb)
 496 {
 497         struct pep_sock *pn = pep_sk(sk);
 498         struct pnpipehdr *hdr;
 499         u8 n_sb;
 500
 501         if (!pskb_pull(skb, sizeof(*hdr) + 4))
 502                 return -EINVAL;
 503
 504         hdr = pnp_hdr(skb);
 505         if (hdr->error_code != PN_PIPE_NO_ERROR)
 506                 return -ECONNREFUSED;
 507
 508         /* Parse sub-blocks */
 509         n_sb = hdr->data[4];
 510         while (n_sb > 0) {
 511                 u8 type, buf[6], len = sizeof(buf);
 512                 const u8 *data = pep_get_sb(skb, &type, &len, buf);
 513
 514                 if (data == NULL)
 515                         return -EINVAL;
 516
 517                 switch (type) {
 518                 case PN_PIPE_SB_REQUIRED_FC_TX:
 519                         if (len < 2 || len < data[0])
 520                                 break;
 521                         pn->tx_fc = pipe_negotiate_fc(data + 2, len - 2);
 522                         break;
 523
 524                 case PN_PIPE_SB_PREFERRED_FC_RX:
 525                         if (len < 2 || len < data[0])
 526                                 break;
 527                         pn->rx_fc = pipe_negotiate_fc(data + 2, len - 2);
 528                         break;
 529
 530                 }
 531                 n_sb--;
 532         }
 533
 534         return pipe_handler_send_created_ind(sk);
 535 }
 536
 537 static int pep_enableresp_rcv(struct sock *sk, struct sk_buff *skb)
 538 {
 539         struct pnpipehdr *hdr = pnp_hdr(skb);
 540
 541         if (hdr->error_code != PN_PIPE_NO_ERROR)
 542                 return -ECONNREFUSED;
 543
 544         return pep_indicate(sk, PNS_PIPE_ENABLED_IND, 0 /* sub-blocks */,
 545                 NULL, 0, GFP_ATOMIC);
 546
 547 }
 548
 549 static void pipe_start_flow_control(struct sock *sk)
 550 {
 551         struct pep_sock *pn = pep_sk(sk);
 552
 553         if (!pn_flow_safe(pn->tx_fc)) {
 554                 atomic_set(&pn->tx_credits, 1);
 555                 sk->sk_write_space(sk);
 556         }
 557         pipe_grant_credits(sk, GFP_ATOMIC);
 558 }
 559
 560 /* Queue an skb to an actively connected sock.
 561  * Socket lock must be held. */
 562 static int pipe_handler_do_rcv(struct sock *sk, struct sk_buff *skb)
 563 {
 564         struct pep_sock *pn = pep_sk(sk);
 565         struct pnpipehdr *hdr = pnp_hdr(skb);
 566         int err = NET_RX_SUCCESS;
 567
 568         switch (hdr->message_id) {
 569         case PNS_PIPE_ALIGNED_DATA:
 570                 __skb_pull(skb, 1);
 571                 /* fall through */
 572         case PNS_PIPE_DATA:
 573                 __skb_pull(skb, 3); /* Pipe data header */
 574                 if (!pn_flow_safe(pn->rx_fc)) {
 575                         err = sock_queue_rcv_skb(sk, skb);
 576                         if (!err)
 577                                 return NET_RX_SUCCESS;
 578                         err = NET_RX_DROP;
 579                         break;
 580                 }
 581
 582                 if (pn->rx_credits == 0) {
 583                         atomic_inc(&sk->sk_drops);
 584                         err = NET_RX_DROP;
 585                         break;
 586                 }
 587                 pn->rx_credits--;
 588                 skb->dev = NULL;
 589                 skb_set_owner_r(skb, sk);
 590                 err = skb->len;
 591                 skb_queue_tail(&sk->sk_receive_queue, skb);
 592                 if (!sock_flag(sk, SOCK_DEAD))
 593                         sk->sk_data_ready(sk, err);
 594                 return NET_RX_SUCCESS;
 595
 596         case PNS_PEP_CONNECT_RESP:
 597                 if (sk->sk_state != TCP_SYN_SENT)
 598                         break;
 599                 if (!sock_flag(sk, SOCK_DEAD))
 600                         sk->sk_state_change(sk);
 601                 if (pep_connresp_rcv(sk, skb)) {
 602                         sk->sk_state = TCP_CLOSE_WAIT;
 603                         break;
 604                 }
 605                 if (pn->init_enable == PN_PIPE_DISABLE)
 606                         sk->sk_state = TCP_SYN_RECV;
 607                 else {
 608                         sk->sk_state = TCP_ESTABLISHED;
 609                         pipe_start_flow_control(sk);
 610                 }
 611                 break;
 612
 613         case PNS_PEP_ENABLE_RESP:
 614                 if (sk->sk_state != TCP_SYN_SENT)
 615                         break;
 616
 617                 if (pep_enableresp_rcv(sk, skb)) {
 618                         sk->sk_state = TCP_CLOSE_WAIT;
 619                         break;
 620                 }
 621
 622                 sk->sk_state = TCP_ESTABLISHED;
 623                 pipe_start_flow_control(sk);
 624                 break;
 625
 626         case PNS_PEP_DISCONNECT_RESP:
 627                 /* sock should already be dead, nothing to do */
 628                 break;
 629
 630         case PNS_PEP_STATUS_IND:
 631                 pipe_rcv_status(sk, skb);
 632                 break;
 633         }
 634         kfree_skb(skb);
 635         return err;
 636 }
 637
 638 /* Listening sock must be locked */
 639 static struct sock *pep_find_pipe(const struct hlist_head *hlist,
 640                                         const struct sockaddr_pn *dst,
 641                                         u8 pipe_handle)
 642 {
 643         struct sock *sknode;
 644         u16 dobj = pn_sockaddr_get_object(dst);
 645
 646         sk_for_each(sknode, hlist) {
 647                 struct pep_sock *pnnode = pep_sk(sknode);
 648
 649                 /* Ports match, but addresses might not: */
 650                 if (pnnode->pn_sk.sobject != dobj)
 651                         continue;
 652                 if (pnnode->pipe_handle != pipe_handle)
 653                         continue;
 654                 if (sknode->sk_state == TCP_CLOSE_WAIT)
 655                         continue;
 656
 657                 sock_hold(sknode);
 658                 return sknode;
 659         }
 660         return NULL;
 661 }
 662
 663 /*
 664  * Deliver an skb to a listening sock.
 665  * Socket lock must be held.
 666  * We then queue the skb to the right connected sock (if any).
 667  */
 668 static int pep_do_rcv(struct sock *sk, struct sk_buff *skb)
 669 {
 670         struct pep_sock *pn = pep_sk(sk);
 671         struct sock *sknode;
 672         struct pnpipehdr *hdr;
 673         struct sockaddr_pn dst;
 674         u8 pipe_handle;
 675
 676         if (!pskb_may_pull(skb, sizeof(*hdr)))
 677                 goto drop;
 678
 679         hdr = pnp_hdr(skb);
 680         pipe_handle = hdr->pipe_handle;
 681         if (pipe_handle == PN_PIPE_INVALID_HANDLE)
 682                 goto drop;
 683
 684         pn_skb_get_dst_sockaddr(skb, &dst);
 685
 686         /* Look for an existing pipe handle */
 687         sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
 688         if (sknode)
 689                 return sk_receive_skb(sknode, skb, 1);
 690
 691         switch (hdr->message_id) {
 692         case PNS_PEP_CONNECT_REQ:
 693                 if (sk->sk_state != TCP_LISTEN || sk_acceptq_is_full(sk)) {
 694                         pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE,
 695                                         GFP_ATOMIC);
 696                         break;
 697                 }
 698                 skb_queue_head(&sk->sk_receive_queue, skb);
 699                 sk_acceptq_added(sk);
 700                 if (!sock_flag(sk, SOCK_DEAD))
 701                         sk->sk_data_ready(sk, 0);
 702                 return NET_RX_SUCCESS;
 703
 704         case PNS_PEP_DISCONNECT_REQ:
 705                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 706                 break;
 707
 708         case PNS_PEP_CTRL_REQ:
 709                 pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC);
 710                 break;
 711
 712         case PNS_PEP_RESET_REQ:
 713         case PNS_PEP_ENABLE_REQ:
 714         case PNS_PEP_DISABLE_REQ:
 715                 /* invalid handle is not even allowed here! */
 716                 break;
 717
 718         default:
 719                 if ((1 << sk->sk_state)
 720                                 & ~(TCPF_CLOSE|TCPF_LISTEN|TCPF_CLOSE_WAIT))
 721                         /* actively connected socket */
 722                         return pipe_handler_do_rcv(sk, skb);
 723         }
 724 drop:
 725         kfree_skb(skb);
 726         return NET_RX_SUCCESS;
 727 }
 728
 729 static int pipe_do_remove(struct sock *sk)
 730 {
 731         struct pep_sock *pn = pep_sk(sk);
 732         struct pnpipehdr *ph;
 733         struct sk_buff *skb;
 734
 735         skb = pep_alloc_skb(sk, NULL, 0, GFP_KERNEL);
 736         if (!skb)
 737                 return -ENOMEM;
 738
 739         ph = pnp_hdr(skb);
 740         ph->utid = 0;
 741         ph->message_id = PNS_PIPE_REMOVE_REQ;
 742         ph->pipe_handle = pn->pipe_handle;
 743         ph->data[0] = PAD;
 744         return pn_skb_send(sk, skb, NULL);
 745 }
 746
 747 /* associated socket ceases to exist */
 748 static void pep_sock_close(struct sock *sk, long timeout)
 749 {
 750         struct pep_sock *pn = pep_sk(sk);
 751         int ifindex = 0;
 752
 753         sock_hold(sk); /* keep a reference after sk_common_release() */
 754         sk_common_release(sk);
 755
 756         lock_sock(sk);
 757         if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED)) {
 758                 if (sk->sk_backlog_rcv == pipe_do_rcv)
 759                         /* Forcefully remove dangling Phonet pipe */
 760                         pipe_do_remove(sk);
 761                 else
 762                         pipe_handler_request(sk, PNS_PEP_DISCONNECT_REQ, PAD,
 763                                                 NULL, 0);
 764         }
 765         sk->sk_state = TCP_CLOSE;
 766
 767         ifindex = pn->ifindex;
 768         pn->ifindex = 0;
 769         release_sock(sk);
 770
 771         if (ifindex)
 772                 gprs_detach(sk);
 773         sock_put(sk);
 774 }
 775
 776 static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp)
 777 {
 778         struct pep_sock *pn = pep_sk(sk), *newpn;
 779         struct sock *newsk = NULL;
 780         struct sk_buff *skb;
 781         struct pnpipehdr *hdr;
 782         struct sockaddr_pn dst, src;
 783         int err;
 784         u16 peer_type;
 785         u8 pipe_handle, enabled, n_sb;
 786         u8 aligned = 0;
 787
 788         skb = skb_recv_datagram(sk, 0, flags & O_NONBLOCK, errp);
 789         if (!skb)
 790                 return NULL;
 791
 792         lock_sock(sk);
 793         if (sk->sk_state != TCP_LISTEN) {
 794                 err = -EINVAL;
 795                 goto drop;
 796         }
 797         sk_acceptq_removed(sk);
 798
 799         err = -EPROTO;
 800         if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
 801                 goto drop;
 802
 803         hdr = pnp_hdr(skb);
 804         pipe_handle = hdr->pipe_handle;
 805         switch (hdr->state_after_connect) {
 806         case PN_PIPE_DISABLE:
 807                 enabled = 0;
 808                 break;
 809         case PN_PIPE_ENABLE:
 810                 enabled = 1;
 811                 break;
 812         default:
 813                 pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM,
 814                                 GFP_KERNEL);
 815                 goto drop;
 816         }
 817         peer_type = hdr->other_pep_type << 8;
 818
 819         /* Parse sub-blocks (options) */
 820         n_sb = hdr->data[4];
 821         while (n_sb > 0) {
 822                 u8 type, buf[1], len = sizeof(buf);
 823                 const u8 *data = pep_get_sb(skb, &type, &len, buf);
 824
 825                 if (data == NULL)
 826                         goto drop;
 827                 switch (type) {
 828                 case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE:
 829                         if (len < 1)
 830                                 goto drop;
 831                         peer_type = (peer_type & 0xff00) | data[0];
 832                         break;
 833                 case PN_PIPE_SB_ALIGNED_DATA:
 834                         aligned = data[0] != 0;
 835                         break;
 836                 }
 837                 n_sb--;
 838         }
 839
 840         /* Check for duplicate pipe handle */
 841         newsk = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
 842         if (unlikely(newsk)) {
 843                 __sock_put(newsk);
 844                 newsk = NULL;
 845                 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_KERNEL);
 846                 goto drop;
 847         }
 848
 849         /* Create a new to-be-accepted sock */
 850         newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_KERNEL, sk->sk_prot);
 851         if (!newsk) {
 852                 pep_reject_conn(sk, skb, PN_PIPE_ERR_OVERLOAD, GFP_KERNEL);
 853                 err = -ENOBUFS;
 854                 goto drop;
 855         }
 856
 857         sock_init_data(NULL, newsk);
 858         newsk->sk_state = TCP_SYN_RECV;
 859         newsk->sk_backlog_rcv = pipe_do_rcv;
 860         newsk->sk_protocol = sk->sk_protocol;
 861         newsk->sk_destruct = pipe_destruct;
 862
 863         newpn = pep_sk(newsk);
 864         pn_skb_get_dst_sockaddr(skb, &dst);
 865         pn_skb_get_src_sockaddr(skb, &src);
 866         newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst);
 867         newpn->pn_sk.dobject = pn_sockaddr_get_object(&src);
 868         newpn->pn_sk.resource = pn_sockaddr_get_resource(&dst);
 869         sock_hold(sk);
 870         newpn->listener = sk;
 871         skb_queue_head_init(&newpn->ctrlreq_queue);
 872         newpn->pipe_handle = pipe_handle;
 873         atomic_set(&newpn->tx_credits, 0);
 874         newpn->ifindex = 0;
 875         newpn->peer_type = peer_type;
 876         newpn->rx_credits = 0;
 877         newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL;
 878         newpn->init_enable = enabled;
 879         newpn->aligned = aligned;
 880
 881         err = pep_accept_conn(newsk, skb);
 882         if (err) {
 883                 sock_put(newsk);
 884                 newsk = NULL;
 885                 goto drop;
 886         }
 887         sk_add_node(newsk, &pn->hlist);
 888 drop:
 889         release_sock(sk);
 890         kfree_skb(skb);
 891         *errp = err;
 892         return newsk;
 893 }
 894
 895 static int pep_sock_connect(struct sock *sk, struct sockaddr *addr, int len)
 896 {
 897         struct pep_sock *pn = pep_sk(sk);
 898         int err;
 899         u8 data[4] = { 0 /* sub-blocks */, PAD, PAD, PAD };
 900
 901         if (pn->pipe_handle == PN_PIPE_INVALID_HANDLE)
 902                 pn->pipe_handle = 1; /* anything but INVALID_HANDLE */
 903
 904         err = pipe_handler_request(sk, PNS_PEP_CONNECT_REQ,
 905                                 pn->init_enable, data, 4);
 906         if (err) {
 907                 pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
 908                 return err;
 909         }
 910
 911         sk->sk_state = TCP_SYN_SENT;
 912
 913         return 0;
 914 }
 915
 916 static int pep_sock_enable(struct sock *sk, struct sockaddr *addr, int len)
 917 {
 918         int err;
 919
 920         err = pipe_handler_request(sk, PNS_PEP_ENABLE_REQ, PAD,
 921                                 NULL, 0);
 922         if (err)
 923                 return err;
 924
 925         sk->sk_state = TCP_SYN_SENT;
 926
 927         return 0;
 928 }
 929
 930 static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg)
 931 {
 932         struct pep_sock *pn = pep_sk(sk);
 933         int answ;
 934         int ret = -ENOIOCTLCMD;
 935
 936         switch (cmd) {
 937         case SIOCINQ:
 938                 if (sk->sk_state == TCP_LISTEN) {
 939                         ret = -EINVAL;
 940                         break;
 941                 }
 942
 943                 lock_sock(sk);
 944                 if (sock_flag(sk, SOCK_URGINLINE) &&
 945                     !skb_queue_empty(&pn->ctrlreq_queue))
 946                         answ = skb_peek(&pn->ctrlreq_queue)->len;
 947                 else if (!skb_queue_empty(&sk->sk_receive_queue))
 948                         answ = skb_peek(&sk->sk_receive_queue)->len;
 949                 else
 950                         answ = 0;
 951                 release_sock(sk);
 952                 ret = put_user(answ, (int __user *)arg);
 953                 break;
 954
 955         case SIOCPNENABLEPIPE:
 956                 lock_sock(sk);
 957                 if (sk->sk_state == TCP_SYN_SENT)
 958                         ret =  -EBUSY;
 959                 else if (sk->sk_state == TCP_ESTABLISHED)
 960                         ret = -EISCONN;
 961                 else
 962                         ret = pep_sock_enable(sk, NULL, 0);
 963                 release_sock(sk);
 964                 break;
 965         }
 966
 967         return ret;
 968 }
 969
 970 static int pep_init(struct sock *sk)
 971 {
 972         struct pep_sock *pn = pep_sk(sk);
 973
 974         sk->sk_destruct = pipe_destruct;
 975         INIT_HLIST_HEAD(&pn->hlist);
 976         pn->listener = NULL;
 977         skb_queue_head_init(&pn->ctrlreq_queue);
 978         atomic_set(&pn->tx_credits, 0);
 979         pn->ifindex = 0;
 980         pn->peer_type = 0;
 981         pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
 982         pn->rx_credits = 0;
 983         pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
 984         pn->init_enable = 1;
 985         pn->aligned = 0;
 986         return 0;
 987 }
 988
 989 static int pep_setsockopt(struct sock *sk, int level, int optname,
 990                                 char __user *optval, unsigned int optlen)
 991 {
 992         struct pep_sock *pn = pep_sk(sk);
 993         int val = 0, err = 0;
 994
 995         if (level != SOL_PNPIPE)
 996                 return -ENOPROTOOPT;
 997         if (optlen >= sizeof(int)) {
 998                 if (get_user(val, (int __user *) optval))
 999                         return -EFAULT;
1000         }
1001
1002         lock_sock(sk);
1003         switch (optname) {
1004         case PNPIPE_ENCAP:
1005                 if (val && val != PNPIPE_ENCAP_IP) {
1006                         err = -EINVAL;
1007                         break;
1008                 }
1009                 if (!pn->ifindex == !val)
1010                         break; /* Nothing to do! */
1011                 if (!capable(CAP_NET_ADMIN)) {
1012                         err = -EPERM;
1013                         break;
1014                 }
1015                 if (val) {
1016                         release_sock(sk);
1017                         err = gprs_attach(sk);
1018                         if (err > 0) {
1019                                 pn->ifindex = err;
1020                                 err = 0;
1021                         }
1022                 } else {
1023                         pn->ifindex = 0;
1024                         release_sock(sk);
1025                         gprs_detach(sk);
1026                         err = 0;
1027                 }
1028                 goto out_norel;
1029
1030         case PNPIPE_HANDLE:
1031                 if ((sk->sk_state == TCP_CLOSE) &&
1032                         (val >= 0) && (val < PN_PIPE_INVALID_HANDLE))
1033                         pn->pipe_handle = val;
1034                 else
1035                         err = -EINVAL;
1036                 break;
1037
1038         case PNPIPE_INITSTATE:
1039                 pn->init_enable = !!val;
1040                 break;
1041
1042         default:
1043                 err = -ENOPROTOOPT;
1044         }
1045         release_sock(sk);
1046
1047 out_norel:
1048         return err;
1049 }
1050
1051 static int pep_getsockopt(struct sock *sk, int level, int optname,
1052                                 char __user *optval, int __user *optlen)
1053 {
1054         struct pep_sock *pn = pep_sk(sk);
1055         int len, val;
1056
1057         if (level != SOL_PNPIPE)
1058                 return -ENOPROTOOPT;
1059         if (get_user(len, optlen))
1060                 return -EFAULT;
1061
1062         switch (optname) {
1063         case PNPIPE_ENCAP:
1064                 val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE;
1065                 break;
1066
1067         case PNPIPE_IFINDEX:
1068                 val = pn->ifindex;
1069                 break;
1070
1071         case PNPIPE_HANDLE:
1072                 val = pn->pipe_handle;
1073                 if (val == PN_PIPE_INVALID_HANDLE)
1074                         return -EINVAL;
1075                 break;
1076
1077         case PNPIPE_INITSTATE:
1078                 val = pn->init_enable;
1079                 break;
1080
1081         default:
1082                 return -ENOPROTOOPT;
1083         }
1084
1085         len = min_t(unsigned int, sizeof(int), len);
1086         if (put_user(len, optlen))
1087                 return -EFAULT;
1088         if (put_user(val, (int __user *) optval))
1089                 return -EFAULT;
1090         return 0;
1091 }
1092
1093 static int pipe_skb_send(struct sock *sk, struct sk_buff *skb)
1094 {
1095         struct pep_sock *pn = pep_sk(sk);
1096         struct pnpipehdr *ph;
1097         int err;
1098
1099         if (pn_flow_safe(pn->tx_fc) &&
1100             !atomic_add_unless(&pn->tx_credits, -1, 0)) {
1101                 kfree_skb(skb);
1102                 return -ENOBUFS;
1103         }
1104
1105         skb_push(skb, 3 + pn->aligned);
1106         skb_reset_transport_header(skb);
1107         ph = pnp_hdr(skb);
1108         ph->utid = 0;
1109         if (pn->aligned) {
1110                 ph->message_id = PNS_PIPE_ALIGNED_DATA;
1111                 ph->data[0] = 0; /* padding */
1112         } else
1113                 ph->message_id = PNS_PIPE_DATA;
1114         ph->pipe_handle = pn->pipe_handle;
1115         err = pn_skb_send(sk, skb, NULL);
1116
1117         if (err && pn_flow_safe(pn->tx_fc))
1118                 atomic_inc(&pn->tx_credits);
1119         return err;
1120
1121 }
1122
1123 static int pep_sendmsg(struct kiocb *iocb, struct sock *sk,
1124                         struct msghdr *msg, size_t len)
1125 {
1126         struct pep_sock *pn = pep_sk(sk);
1127         struct sk_buff *skb;
1128         long timeo;
1129         int flags = msg->msg_flags;
1130         int err, done;
1131
1132         if (len > USHRT_MAX)
1133                 return -EMSGSIZE;
1134
1135         if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|
1136                                 MSG_CMSG_COMPAT)) ||
1137                         !(msg->msg_flags & MSG_EOR))
1138                 return -EOPNOTSUPP;
1139
1140         skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len,
1141                                         flags & MSG_DONTWAIT, &err);
1142         if (!skb)
1143                 return err;
1144
1145         skb_reserve(skb, MAX_PHONET_HEADER + 3 + pn->aligned);
1146         err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1147         if (err < 0)
1148                 goto outfree;
1149
1150         lock_sock(sk);
1151         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1152         if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) {
1153                 err = -ENOTCONN;
1154                 goto out;
1155         }
1156         if (sk->sk_state != TCP_ESTABLISHED) {
1157                 /* Wait until the pipe gets to enabled state */
1158 disabled:
1159                 err = sk_stream_wait_connect(sk, &timeo);
1160                 if (err)
1161                         goto out;
1162
1163                 if (sk->sk_state == TCP_CLOSE_WAIT) {
1164                         err = -ECONNRESET;
1165                         goto out;
1166                 }
1167         }
1168         BUG_ON(sk->sk_state != TCP_ESTABLISHED);
1169
1170         /* Wait until flow control allows TX */
1171         done = atomic_read(&pn->tx_credits);
1172         while (!done) {
1173                 DEFINE_WAIT(wait);
1174
1175                 if (!timeo) {
1176                         err = -EAGAIN;
1177                         goto out;
1178                 }
1179                 if (signal_pending(current)) {
1180                         err = sock_intr_errno(timeo);
1181                         goto out;
1182                 }
1183
1184                 prepare_to_wait(sk_sleep(sk), &wait,
1185                                 TASK_INTERRUPTIBLE);
1186                 done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits));
1187                 finish_wait(sk_sleep(sk), &wait);
1188
1189                 if (sk->sk_state != TCP_ESTABLISHED)
1190                         goto disabled;
1191         }
1192
1193         err = pipe_skb_send(sk, skb);
1194         if (err >= 0)
1195                 err = len; /* success! */
1196         skb = NULL;
1197 out:
1198         release_sock(sk);
1199 outfree:
1200         kfree_skb(skb);
1201         return err;
1202 }
1203
1204 int pep_writeable(struct sock *sk)
1205 {
1206         struct pep_sock *pn = pep_sk(sk);
1207
1208         return atomic_read(&pn->tx_credits);
1209 }
1210
1211 int pep_write(struct sock *sk, struct sk_buff *skb)
1212 {
1213         struct sk_buff *rskb, *fs;
1214         int flen = 0;
1215
1216         if (pep_sk(sk)->aligned)
1217                 return pipe_skb_send(sk, skb);
1218
1219         rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC);
1220         if (!rskb) {
1221                 kfree_skb(skb);
1222                 return -ENOMEM;
1223         }
1224         skb_shinfo(rskb)->frag_list = skb;
1225         rskb->len += skb->len;
1226         rskb->data_len += rskb->len;
1227         rskb->truesize += rskb->len;
1228
1229         /* Avoid nested fragments */
1230         skb_walk_frags(skb, fs)
1231                 flen += fs->len;
1232         skb->next = skb_shinfo(skb)->frag_list;
1233         skb_frag_list_init(skb);
1234         skb->len -= flen;
1235         skb->data_len -= flen;
1236         skb->truesize -= flen;
1237
1238         skb_reserve(rskb, MAX_PHONET_HEADER + 3);
1239         return pipe_skb_send(sk, rskb);
1240 }
1241
1242 struct sk_buff *pep_read(struct sock *sk)
1243 {
1244         struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue);
1245
1246         if (sk->sk_state == TCP_ESTABLISHED)
1247                 pipe_grant_credits(sk, GFP_ATOMIC);
1248         return skb;
1249 }
1250
1251 static int pep_recvmsg(struct kiocb *iocb, struct sock *sk,
1252                         struct msghdr *msg, size_t len, int noblock,
1253                         int flags, int *addr_len)
1254 {
1255         struct sk_buff *skb;
1256         int err;
1257
1258         if (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL|
1259                         MSG_NOSIGNAL|MSG_CMSG_COMPAT))
1260                 return -EOPNOTSUPP;
1261
1262         if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE)))
1263                 return -ENOTCONN;
1264
1265         if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) {
1266                 /* Dequeue and acknowledge control request */
1267                 struct pep_sock *pn = pep_sk(sk);
1268
1269                 if (flags & MSG_PEEK)
1270                         return -EOPNOTSUPP;
1271                 skb = skb_dequeue(&pn->ctrlreq_queue);
1272                 if (skb) {
1273                         pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR,
1274                                                 GFP_KERNEL);
1275                         msg->msg_flags |= MSG_OOB;
1276                         goto copy;
1277                 }
1278                 if (flags & MSG_OOB)
1279                         return -EINVAL;
1280         }
1281
1282         skb = skb_recv_datagram(sk, flags, noblock, &err);
1283         lock_sock(sk);
1284         if (skb == NULL) {
1285                 if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT)
1286                         err = -ECONNRESET;
1287                 release_sock(sk);
1288                 return err;
1289         }
1290
1291         if (sk->sk_state == TCP_ESTABLISHED)
1292                 pipe_grant_credits(sk, GFP_KERNEL);
1293         release_sock(sk);
1294 copy:
1295         msg->msg_flags |= MSG_EOR;
1296         if (skb->len > len)
1297                 msg->msg_flags |= MSG_TRUNC;
1298         else
1299                 len = skb->len;
1300
1301         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len);
1302         if (!err)
1303                 err = (flags & MSG_TRUNC) ? skb->len : len;
1304
1305         skb_free_datagram(sk, skb);
1306         return err;
1307 }
1308
1309 static void pep_sock_unhash(struct sock *sk)
1310 {
1311         struct pep_sock *pn = pep_sk(sk);
1312         struct sock *skparent = NULL;
1313
1314         lock_sock(sk);
1315
1316         if (pn->listener != NULL) {
1317                 skparent = pn->listener;
1318                 pn->listener = NULL;
1319                 release_sock(sk);
1320
1321                 pn = pep_sk(skparent);
1322                 lock_sock(skparent);
1323                 sk_del_node_init(sk);
1324                 sk = skparent;
1325         }
1326
1327         /* Unhash a listening sock only when it is closed
1328          * and all of its active connected pipes are closed. */
1329         if (hlist_empty(&pn->hlist))
1330                 pn_sock_unhash(&pn->pn_sk.sk);
1331         release_sock(sk);
1332
1333         if (skparent)
1334                 sock_put(skparent);
1335 }
1336
1337 static struct proto pep_proto = {
1338         .close          = pep_sock_close,
1339         .accept         = pep_sock_accept,
1340         .connect        = pep_sock_connect,
1341         .ioctl          = pep_ioctl,
1342         .init           = pep_init,
1343         .setsockopt     = pep_setsockopt,
1344         .getsockopt     = pep_getsockopt,
1345         .sendmsg        = pep_sendmsg,
1346         .recvmsg        = pep_recvmsg,
1347         .backlog_rcv    = pep_do_rcv,
1348         .hash           = pn_sock_hash,
1349         .unhash         = pep_sock_unhash,
1350         .get_port       = pn_sock_get_port,
1351         .obj_size       = sizeof(struct pep_sock),
1352         .owner          = THIS_MODULE,
1353         .name           = "PNPIPE",
1354 };
1355
1356 static struct phonet_protocol pep_pn_proto = {
1357         .ops            = &phonet_stream_ops,
1358         .prot           = &pep_proto,
1359         .sock_type      = SOCK_SEQPACKET,
1360 };
1361
1362 static int __init pep_register(void)
1363 {
1364         return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto);
1365 }
1366
1367 static void __exit pep_unregister(void)
1368 {
1369         phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto);
1370 }
1371
1372 module_init(pep_register);
1373 module_exit(pep_unregister);
1374 MODULE_AUTHOR("Remi Denis-Courmont, Nokia");
1375 MODULE_DESCRIPTION("Phonet pipe protocol");
1376 MODULE_LICENSE("GPL");
1377 MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE);