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 <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/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 <net/phonet/phonet.h>
  34 #include <net/phonet/pep.h>
  35 #include <net/phonet/gprs.h>
  36
  37 /* sk_state values:
  38  * TCP_CLOSE            sock not in use yet
  39  * TCP_CLOSE_WAIT       disconnected pipe
  40  * TCP_LISTEN           listening pipe endpoint
  41  * TCP_SYN_RECV         connected pipe in disabled state
  42  * TCP_ESTABLISHED      connected pipe in enabled state
  43  *
  44  * pep_sock locking:
  45  *  - sk_state, ackq, hlist: sock lock needed
  46  *  - listener: read only
  47  *  - pipe_handle: read only
  48  */
  49
  50 #define CREDITS_MAX     10
  51 #define CREDITS_THR     7
  52
  53 static const struct sockaddr_pn pipe_srv = {
  54         .spn_family = AF_PHONET,
  55         .spn_resource = 0xD9, /* pipe service */
  56 };
  57
  58 #define pep_sb_size(s) (((s) + 5) & ~3) /* 2-bytes head, 32-bits aligned */
  59
  60 /* Get the next TLV sub-block. */
  61 static unsigned char *pep_get_sb(struct sk_buff *skb, u8 *ptype, u8 *plen,
  62                                         void *buf)
  63 {
  64         void *data = NULL;
  65         struct {
  66                 u8 sb_type;
  67                 u8 sb_len;
  68         } *ph, h;
  69         int buflen = *plen;
  70
  71         ph = skb_header_pointer(skb, 0, 2, &h);
  72         if (ph == NULL || ph->sb_len < 2 || !pskb_may_pull(skb, ph->sb_len))
  73                 return NULL;
  74         ph->sb_len -= 2;
  75         *ptype = ph->sb_type;
  76         *plen = ph->sb_len;
  77
  78         if (buflen > ph->sb_len)
  79                 buflen = ph->sb_len;
  80         data = skb_header_pointer(skb, 2, buflen, buf);
  81         __skb_pull(skb, 2 + ph->sb_len);
  82         return data;
  83 }
  84
  85 static int pep_reply(struct sock *sk, struct sk_buff *oskb,
  86                         u8 code, const void *data, int len, gfp_t priority)
  87 {
  88         const struct pnpipehdr *oph = pnp_hdr(oskb);
  89         struct pnpipehdr *ph;
  90         struct sk_buff *skb;
  91
  92         skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority);
  93         if (!skb)
  94                 return -ENOMEM;
  95         skb_set_owner_w(skb, sk);
  96
  97         skb_reserve(skb, MAX_PNPIPE_HEADER);
  98         __skb_put(skb, len);
  99         skb_copy_to_linear_data(skb, data, len);
 100         __skb_push(skb, sizeof(*ph));
 101         skb_reset_transport_header(skb);
 102         ph = pnp_hdr(skb);
 103         ph->utid = oph->utid;
 104         ph->message_id = oph->message_id + 1; /* REQ -> RESP */
 105         ph->pipe_handle = oph->pipe_handle;
 106         ph->error_code = code;
 107
 108         return pn_skb_send(sk, skb, &pipe_srv);
 109 }
 110
 111 #define PAD 0x00
 112
 113 #ifdef CONFIG_PHONET_PIPECTRLR
 114 static u8 pipe_negotiate_fc(u8 *host_fc, u8 *remote_fc, int len)
 115 {
 116         int i, j;
 117         u8 base_fc, final_fc;
 118
 119         for (i = 0; i < len; i++) {
 120                 base_fc = host_fc[i];
 121                 for (j = 0; j < len; j++) {
 122                         if (remote_fc[j] == base_fc) {
 123                                 final_fc = base_fc;
 124                                 goto done;
 125                         }
 126                 }
 127         }
 128         return -EINVAL;
 129
 130 done:
 131         return final_fc;
 132
 133 }
 134
 135 static int pipe_get_flow_info(struct sock *sk, struct sk_buff *skb,
 136                 u8 *pref_rx_fc, u8 *req_tx_fc)
 137 {
 138         struct pnpipehdr *hdr;
 139         u8 n_sb;
 140
 141         if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
 142                 return -EINVAL;
 143
 144         hdr = pnp_hdr(skb);
 145         n_sb = hdr->data[4];
 146
 147         __skb_pull(skb, sizeof(*hdr) + 4);
 148         while (n_sb > 0) {
 149                 u8 type, buf[3], len = sizeof(buf);
 150                 u8 *data = pep_get_sb(skb, &type, &len, buf);
 151
 152                 if (data == NULL)
 153                         return -EINVAL;
 154
 155                 switch (type) {
 156                 case PN_PIPE_SB_REQUIRED_FC_TX:
 157                         if (len < 3 || (data[2] | data[3] | data[4]) > 3)
 158                                 break;
 159                         req_tx_fc[0] = data[2];
 160                         req_tx_fc[1] = data[3];
 161                         req_tx_fc[2] = data[4];
 162                         break;
 163
 164                 case PN_PIPE_SB_PREFERRED_FC_RX:
 165                         if (len < 3 || (data[2] | data[3] | data[4]) > 3)
 166                                 break;
 167                         pref_rx_fc[0] = data[2];
 168                         pref_rx_fc[1] = data[3];
 169                         pref_rx_fc[2] = data[4];
 170                         break;
 171
 172                 }
 173                 n_sb--;
 174         }
 175         return 0;
 176 }
 177
 178 static int pipe_handler_send_req(struct sock *sk, u8 utid,
 179                 u8 msg_id, gfp_t priority)
 180 {
 181         int len;
 182         struct pnpipehdr *ph;
 183         struct sk_buff *skb;
 184         struct pep_sock *pn = pep_sk(sk);
 185
 186         static const u8 data[4] = {
 187                 PAD, PAD, PAD, PAD,
 188         };
 189
 190         switch (msg_id) {
 191         case PNS_PEP_CONNECT_REQ:
 192                 len = sizeof(data);
 193                 break;
 194
 195         case PNS_PEP_DISCONNECT_REQ:
 196         case PNS_PEP_ENABLE_REQ:
 197         case PNS_PEP_DISABLE_REQ:
 198                 len = 0;
 199                 break;
 200
 201         default:
 202                 return -EINVAL;
 203         }
 204
 205         skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority);
 206         if (!skb)
 207                 return -ENOMEM;
 208         skb_set_owner_w(skb, sk);
 209
 210         skb_reserve(skb, MAX_PNPIPE_HEADER);
 211         if (len) {
 212                 __skb_put(skb, len);
 213                 skb_copy_to_linear_data(skb, data, len);
 214         }
 215         __skb_push(skb, sizeof(*ph));
 216         skb_reset_transport_header(skb);
 217         ph = pnp_hdr(skb);
 218         ph->utid = utid;
 219         ph->message_id = msg_id;
 220         ph->pipe_handle = pn->pipe_handle;
 221         ph->error_code = PN_PIPE_NO_ERROR;
 222
 223         return pn_skb_send(sk, skb, &pn->remote_pep);
 224 }
 225
 226 static int pipe_handler_send_created_ind(struct sock *sk,
 227                 u8 utid, u8 msg_id)
 228 {
 229         int err_code;
 230         struct pnpipehdr *ph;
 231         struct sk_buff *skb;
 232
 233         struct pep_sock *pn = pep_sk(sk);
 234         static u8 data[4] = {
 235                 0x03, 0x04,
 236         };
 237         data[2] = pn->tx_fc;
 238         data[3] = pn->rx_fc;
 239
 240         /*
 241          * actually, below is number of sub-blocks and not error code.
 242          * Pipe_created_ind message format does not have any
 243          * error code field. However, the Phonet stack will always send
 244          * an error code as part of pnpipehdr. So, use that err_code to
 245          * specify the number of sub-blocks.
 246          */
 247         err_code = 0x01;
 248
 249         skb = alloc_skb(MAX_PNPIPE_HEADER + sizeof(data), GFP_ATOMIC);
 250         if (!skb)
 251                 return -ENOMEM;
 252         skb_set_owner_w(skb, sk);
 253
 254         skb_reserve(skb, MAX_PNPIPE_HEADER);
 255         __skb_put(skb, sizeof(data));
 256         skb_copy_to_linear_data(skb, data, sizeof(data));
 257         __skb_push(skb, sizeof(*ph));
 258         skb_reset_transport_header(skb);
 259         ph = pnp_hdr(skb);
 260         ph->utid = utid;
 261         ph->message_id = msg_id;
 262         ph->pipe_handle = pn->pipe_handle;
 263         ph->error_code = err_code;
 264
 265         return pn_skb_send(sk, skb, &pn->remote_pep);
 266 }
 267
 268 static int pipe_handler_send_ind(struct sock *sk, u8 utid, u8 msg_id)
 269 {
 270         int err_code;
 271         struct pnpipehdr *ph;
 272         struct sk_buff *skb;
 273         struct pep_sock *pn = pep_sk(sk);
 274
 275         /*
 276          * actually, below is a filler.
 277          * Pipe_enabled/disabled_ind message format does not have any
 278          * error code field. However, the Phonet stack will always send
 279          * an error code as part of pnpipehdr. So, use that err_code to
 280          * specify the filler value.
 281          */
 282         err_code = 0x0;
 283
 284         skb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC);
 285         if (!skb)
 286                 return -ENOMEM;
 287         skb_set_owner_w(skb, sk);
 288
 289         skb_reserve(skb, MAX_PNPIPE_HEADER);
 290         __skb_push(skb, sizeof(*ph));
 291         skb_reset_transport_header(skb);
 292         ph = pnp_hdr(skb);
 293         ph->utid = utid;
 294         ph->message_id = msg_id;
 295         ph->pipe_handle = pn->pipe_handle;
 296         ph->error_code = err_code;
 297
 298         return pn_skb_send(sk, skb, &pn->remote_pep);
 299 }
 300
 301 static int pipe_handler_enable_pipe(struct sock *sk, int enable)
 302 {
 303         int utid, req;
 304
 305         if (enable) {
 306                 utid = PNS_PIPE_ENABLE_UTID;
 307                 req = PNS_PEP_ENABLE_REQ;
 308         } else {
 309                 utid = PNS_PIPE_DISABLE_UTID;
 310                 req = PNS_PEP_DISABLE_REQ;
 311         }
 312         return pipe_handler_send_req(sk, utid, req, GFP_ATOMIC);
 313 }
 314 #endif
 315
 316 static int pep_accept_conn(struct sock *sk, struct sk_buff *skb)
 317 {
 318         static const u8 data[20] = {
 319                 PAD, PAD, PAD, 2 /* sub-blocks */,
 320                 PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD,
 321                         PN_MULTI_CREDIT_FLOW_CONTROL,
 322                         PN_ONE_CREDIT_FLOW_CONTROL,
 323                         PN_LEGACY_FLOW_CONTROL,
 324                         PAD,
 325                 PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD,
 326                         PN_MULTI_CREDIT_FLOW_CONTROL,
 327                         PN_ONE_CREDIT_FLOW_CONTROL,
 328                         PN_LEGACY_FLOW_CONTROL,
 329                         PAD,
 330         };
 331
 332         might_sleep();
 333         return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data),
 334                                 GFP_KERNEL);
 335 }
 336
 337 static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code)
 338 {
 339         static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ };
 340         WARN_ON(code == PN_PIPE_NO_ERROR);
 341         return pep_reply(sk, skb, code, data, sizeof(data), GFP_ATOMIC);
 342 }
 343
 344 /* Control requests are not sent by the pipe service and have a specific
 345  * message format. */
 346 static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code,
 347                                 gfp_t priority)
 348 {
 349         const struct pnpipehdr *oph = pnp_hdr(oskb);
 350         struct sk_buff *skb;
 351         struct pnpipehdr *ph;
 352         struct sockaddr_pn dst;
 353
 354         skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority);
 355         if (!skb)
 356                 return -ENOMEM;
 357         skb_set_owner_w(skb, sk);
 358
 359         skb_reserve(skb, MAX_PHONET_HEADER);
 360         ph = (struct pnpipehdr *)skb_put(skb, sizeof(*ph) + 4);
 361
 362         ph->utid = oph->utid;
 363         ph->message_id = PNS_PEP_CTRL_RESP;
 364         ph->pipe_handle = oph->pipe_handle;
 365         ph->data[0] = oph->data[1]; /* CTRL id */
 366         ph->data[1] = oph->data[0]; /* PEP type */
 367         ph->data[2] = code; /* error code, at an usual offset */
 368         ph->data[3] = PAD;
 369         ph->data[4] = PAD;
 370
 371         pn_skb_get_src_sockaddr(oskb, &dst);
 372         return pn_skb_send(sk, skb, &dst);
 373 }
 374
 375 static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority)
 376 {
 377         struct pep_sock *pn = pep_sk(sk);
 378         struct pnpipehdr *ph;
 379         struct sk_buff *skb;
 380
 381         skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority);
 382         if (!skb)
 383                 return -ENOMEM;
 384         skb_set_owner_w(skb, sk);
 385
 386         skb_reserve(skb, MAX_PNPIPE_HEADER + 4);
 387         __skb_push(skb, sizeof(*ph) + 4);
 388         skb_reset_transport_header(skb);
 389         ph = pnp_hdr(skb);
 390         ph->utid = 0;
 391         ph->message_id = PNS_PEP_STATUS_IND;
 392         ph->pipe_handle = pn->pipe_handle;
 393         ph->pep_type = PN_PEP_TYPE_COMMON;
 394         ph->data[1] = type;
 395         ph->data[2] = PAD;
 396         ph->data[3] = PAD;
 397         ph->data[4] = status;
 398
 399 #ifdef CONFIG_PHONET_PIPECTRLR
 400         return pn_skb_send(sk, skb, &pn->remote_pep);
 401 #else
 402         return pn_skb_send(sk, skb, &pipe_srv);
 403 #endif
 404 }
 405
 406 /* Send our RX flow control information to the sender.
 407  * Socket must be locked. */
 408 static void pipe_grant_credits(struct sock *sk)
 409 {
 410         struct pep_sock *pn = pep_sk(sk);
 411
 412         BUG_ON(sk->sk_state != TCP_ESTABLISHED);
 413
 414         switch (pn->rx_fc) {
 415         case PN_LEGACY_FLOW_CONTROL: /* TODO */
 416                 break;
 417         case PN_ONE_CREDIT_FLOW_CONTROL:
 418                 pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL,
 419                                 PEP_IND_READY, GFP_ATOMIC);
 420                 pn->rx_credits = 1;
 421                 break;
 422         case PN_MULTI_CREDIT_FLOW_CONTROL:
 423                 if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX)
 424                         break;
 425                 if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS,
 426                                         CREDITS_MAX - pn->rx_credits,
 427                                         GFP_ATOMIC) == 0)
 428                         pn->rx_credits = CREDITS_MAX;
 429                 break;
 430         }
 431 }
 432
 433 static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb)
 434 {
 435         struct pep_sock *pn = pep_sk(sk);
 436         struct pnpipehdr *hdr;
 437         int wake = 0;
 438
 439         if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
 440                 return -EINVAL;
 441
 442         hdr = pnp_hdr(skb);
 443         if (hdr->data[0] != PN_PEP_TYPE_COMMON) {
 444                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP type: %u\n",
 445                                 (unsigned)hdr->data[0]);
 446                 return -EOPNOTSUPP;
 447         }
 448
 449         switch (hdr->data[1]) {
 450         case PN_PEP_IND_FLOW_CONTROL:
 451                 switch (pn->tx_fc) {
 452                 case PN_LEGACY_FLOW_CONTROL:
 453                         switch (hdr->data[4]) {
 454                         case PEP_IND_BUSY:
 455                                 atomic_set(&pn->tx_credits, 0);
 456                                 break;
 457                         case PEP_IND_READY:
 458                                 atomic_set(&pn->tx_credits, wake = 1);
 459                                 break;
 460                         }
 461                         break;
 462                 case PN_ONE_CREDIT_FLOW_CONTROL:
 463                         if (hdr->data[4] == PEP_IND_READY)
 464                                 atomic_set(&pn->tx_credits, wake = 1);
 465                         break;
 466                 }
 467                 break;
 468
 469         case PN_PEP_IND_ID_MCFC_GRANT_CREDITS:
 470                 if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL)
 471                         break;
 472                 atomic_add(wake = hdr->data[4], &pn->tx_credits);
 473                 break;
 474
 475         default:
 476                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP indication: %u\n",
 477                                 (unsigned)hdr->data[1]);
 478                 return -EOPNOTSUPP;
 479         }
 480         if (wake)
 481                 sk->sk_write_space(sk);
 482         return 0;
 483 }
 484
 485 static int pipe_rcv_created(struct sock *sk, struct sk_buff *skb)
 486 {
 487         struct pep_sock *pn = pep_sk(sk);
 488         struct pnpipehdr *hdr = pnp_hdr(skb);
 489         u8 n_sb = hdr->data[0];
 490
 491         pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
 492         __skb_pull(skb, sizeof(*hdr));
 493         while (n_sb > 0) {
 494                 u8 type, buf[2], len = sizeof(buf);
 495                 u8 *data = pep_get_sb(skb, &type, &len, buf);
 496
 497                 if (data == NULL)
 498                         return -EINVAL;
 499                 switch (type) {
 500                 case PN_PIPE_SB_NEGOTIATED_FC:
 501                         if (len < 2 || (data[0] | data[1]) > 3)
 502                                 break;
 503                         pn->tx_fc = data[0] & 3;
 504                         pn->rx_fc = data[1] & 3;
 505                         break;
 506                 }
 507                 n_sb--;
 508         }
 509         return 0;
 510 }
 511
 512 /* Queue an skb to a connected sock.
 513  * Socket lock must be held. */
 514 static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
 515 {
 516         struct pep_sock *pn = pep_sk(sk);
 517         struct pnpipehdr *hdr = pnp_hdr(skb);
 518         struct sk_buff_head *queue;
 519         int err = 0;
 520
 521         BUG_ON(sk->sk_state == TCP_CLOSE_WAIT);
 522
 523         switch (hdr->message_id) {
 524         case PNS_PEP_CONNECT_REQ:
 525                 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE);
 526                 break;
 527
 528         case PNS_PEP_DISCONNECT_REQ:
 529                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 530                 sk->sk_state = TCP_CLOSE_WAIT;
 531                 if (!sock_flag(sk, SOCK_DEAD))
 532                         sk->sk_state_change(sk);
 533                 break;
 534
 535 #ifdef CONFIG_PHONET_PIPECTRLR
 536         case PNS_PEP_DISCONNECT_RESP:
 537                 pn->pipe_state = PIPE_IDLE;
 538                 sk->sk_state = TCP_CLOSE;
 539                 break;
 540 #endif
 541
 542         case PNS_PEP_ENABLE_REQ:
 543                 /* Wait for PNS_PIPE_(ENABLED|REDIRECTED)_IND */
 544                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 545                 break;
 546
 547 #ifdef CONFIG_PHONET_PIPECTRLR
 548         case PNS_PEP_ENABLE_RESP:
 549                 pn->pipe_state = PIPE_ENABLED;
 550                 pipe_handler_send_ind(sk, PNS_PIPE_ENABLED_IND_UTID,
 551                                 PNS_PIPE_ENABLED_IND);
 552
 553                 if (!pn_flow_safe(pn->tx_fc)) {
 554                         atomic_set(&pn->tx_credits, 1);
 555                         sk->sk_write_space(sk);
 556                 }
 557                 if (sk->sk_state == TCP_ESTABLISHED)
 558                         break; /* Nothing to do */
 559                 sk->sk_state = TCP_ESTABLISHED;
 560                 pipe_grant_credits(sk);
 561                 break;
 562 #endif
 563
 564         case PNS_PEP_RESET_REQ:
 565                 switch (hdr->state_after_reset) {
 566                 case PN_PIPE_DISABLE:
 567                         pn->init_enable = 0;
 568                         break;
 569                 case PN_PIPE_ENABLE:
 570                         pn->init_enable = 1;
 571                         break;
 572                 default: /* not allowed to send an error here!? */
 573                         err = -EINVAL;
 574                         goto out;
 575                 }
 576                 /* fall through */
 577         case PNS_PEP_DISABLE_REQ:
 578                 atomic_set(&pn->tx_credits, 0);
 579                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 580                 break;
 581
 582 #ifdef CONFIG_PHONET_PIPECTRLR
 583         case PNS_PEP_DISABLE_RESP:
 584                 pn->pipe_state = PIPE_DISABLED;
 585                 atomic_set(&pn->tx_credits, 0);
 586                 pipe_handler_send_ind(sk, PNS_PIPE_DISABLED_IND_UTID,
 587                                 PNS_PIPE_DISABLED_IND);
 588                 sk->sk_state = TCP_SYN_RECV;
 589                 pn->rx_credits = 0;
 590                 break;
 591 #endif
 592
 593         case PNS_PEP_CTRL_REQ:
 594                 if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) {
 595                         atomic_inc(&sk->sk_drops);
 596                         break;
 597                 }
 598                 __skb_pull(skb, 4);
 599                 queue = &pn->ctrlreq_queue;
 600                 goto queue;
 601
 602         case PNS_PIPE_ALIGNED_DATA:
 603                 __skb_pull(skb, 1);
 604                 /* fall through */
 605         case PNS_PIPE_DATA:
 606                 __skb_pull(skb, 3); /* Pipe data header */
 607                 if (!pn_flow_safe(pn->rx_fc)) {
 608                         err = sock_queue_rcv_skb(sk, skb);
 609                         if (!err)
 610                                 return 0;
 611                         break;
 612                 }
 613
 614                 if (pn->rx_credits == 0) {
 615                         atomic_inc(&sk->sk_drops);
 616                         err = -ENOBUFS;
 617                         break;
 618                 }
 619                 pn->rx_credits--;
 620                 queue = &sk->sk_receive_queue;
 621                 goto queue;
 622
 623         case PNS_PEP_STATUS_IND:
 624                 pipe_rcv_status(sk, skb);
 625                 break;
 626
 627         case PNS_PIPE_REDIRECTED_IND:
 628                 err = pipe_rcv_created(sk, skb);
 629                 break;
 630
 631         case PNS_PIPE_CREATED_IND:
 632                 err = pipe_rcv_created(sk, skb);
 633                 if (err)
 634                         break;
 635                 /* fall through */
 636         case PNS_PIPE_RESET_IND:
 637                 if (!pn->init_enable)
 638                         break;
 639                 /* fall through */
 640         case PNS_PIPE_ENABLED_IND:
 641                 if (!pn_flow_safe(pn->tx_fc)) {
 642                         atomic_set(&pn->tx_credits, 1);
 643                         sk->sk_write_space(sk);
 644                 }
 645                 if (sk->sk_state == TCP_ESTABLISHED)
 646                         break; /* Nothing to do */
 647                 sk->sk_state = TCP_ESTABLISHED;
 648                 pipe_grant_credits(sk);
 649                 break;
 650
 651         case PNS_PIPE_DISABLED_IND:
 652                 sk->sk_state = TCP_SYN_RECV;
 653                 pn->rx_credits = 0;
 654                 break;
 655
 656         default:
 657                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP message: %u\n",
 658                                 hdr->message_id);
 659                 err = -EINVAL;
 660         }
 661 out:
 662         kfree_skb(skb);
 663         return err;
 664
 665 queue:
 666         skb->dev = NULL;
 667         skb_set_owner_r(skb, sk);
 668         err = skb->len;
 669         skb_queue_tail(queue, skb);
 670         if (!sock_flag(sk, SOCK_DEAD))
 671                 sk->sk_data_ready(sk, err);
 672         return 0;
 673 }
 674
 675 /* Destroy connected sock. */
 676 static void pipe_destruct(struct sock *sk)
 677 {
 678         struct pep_sock *pn = pep_sk(sk);
 679
 680         skb_queue_purge(&sk->sk_receive_queue);
 681         skb_queue_purge(&pn->ctrlreq_queue);
 682 }
 683
 684 #ifdef CONFIG_PHONET_PIPECTRLR
 685 static int pep_connresp_rcv(struct sock *sk, struct sk_buff *skb)
 686 {
 687         struct pep_sock *pn = pep_sk(sk);
 688         u8 host_pref_rx_fc[3] = {3, 2, 1}, host_req_tx_fc[3] = {3, 2, 1};
 689         u8 remote_pref_rx_fc[3], remote_req_tx_fc[3];
 690         u8 negotiated_rx_fc, negotiated_tx_fc;
 691         int ret;
 692
 693         pipe_get_flow_info(sk, skb, remote_pref_rx_fc,
 694                         remote_req_tx_fc);
 695         negotiated_tx_fc = pipe_negotiate_fc(remote_req_tx_fc,
 696                         host_pref_rx_fc,
 697                         sizeof(host_pref_rx_fc));
 698         negotiated_rx_fc = pipe_negotiate_fc(host_req_tx_fc,
 699                         remote_pref_rx_fc,
 700                         sizeof(host_pref_rx_fc));
 701
 702         pn->pipe_state = PIPE_DISABLED;
 703         sk->sk_state = TCP_SYN_RECV;
 704         sk->sk_backlog_rcv = pipe_do_rcv;
 705         sk->sk_destruct = pipe_destruct;
 706         pn->rx_credits = 0;
 707         pn->rx_fc = negotiated_rx_fc;
 708         pn->tx_fc = negotiated_tx_fc;
 709         sk->sk_state_change(sk);
 710
 711         ret = pipe_handler_send_created_ind(sk,
 712                         PNS_PIPE_CREATED_IND_UTID,
 713                         PNS_PIPE_CREATED_IND
 714                         );
 715
 716         return ret;
 717 }
 718 #endif
 719
 720 static int pep_connreq_rcv(struct sock *sk, struct sk_buff *skb)
 721 {
 722         struct sock *newsk;
 723         struct pep_sock *newpn, *pn = pep_sk(sk);
 724         struct pnpipehdr *hdr;
 725         struct sockaddr_pn dst;
 726         u16 peer_type;
 727         u8 pipe_handle, enabled, n_sb;
 728         u8 aligned = 0;
 729
 730         if (!pskb_pull(skb, sizeof(*hdr) + 4))
 731                 return -EINVAL;
 732
 733         hdr = pnp_hdr(skb);
 734         pipe_handle = hdr->pipe_handle;
 735         switch (hdr->state_after_connect) {
 736         case PN_PIPE_DISABLE:
 737                 enabled = 0;
 738                 break;
 739         case PN_PIPE_ENABLE:
 740                 enabled = 1;
 741                 break;
 742         default:
 743                 pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM);
 744                 return -EINVAL;
 745         }
 746         peer_type = hdr->other_pep_type << 8;
 747
 748         if (unlikely(sk->sk_state != TCP_LISTEN) || sk_acceptq_is_full(sk)) {
 749                 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE);
 750                 return -ENOBUFS;
 751         }
 752
 753         /* Parse sub-blocks (options) */
 754         n_sb = hdr->data[4];
 755         while (n_sb > 0) {
 756                 u8 type, buf[1], len = sizeof(buf);
 757                 const u8 *data = pep_get_sb(skb, &type, &len, buf);
 758
 759                 if (data == NULL)
 760                         return -EINVAL;
 761                 switch (type) {
 762                 case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE:
 763                         if (len < 1)
 764                                 return -EINVAL;
 765                         peer_type = (peer_type & 0xff00) | data[0];
 766                         break;
 767                 case PN_PIPE_SB_ALIGNED_DATA:
 768                         aligned = data[0] != 0;
 769                         break;
 770                 }
 771                 n_sb--;
 772         }
 773
 774         skb = skb_clone(skb, GFP_ATOMIC);
 775         if (!skb)
 776                 return -ENOMEM;
 777
 778         /* Create a new to-be-accepted sock */
 779         newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_ATOMIC, sk->sk_prot);
 780         if (!newsk) {
 781                 kfree_skb(skb);
 782                 return -ENOMEM;
 783         }
 784         sock_init_data(NULL, newsk);
 785         newsk->sk_state = TCP_SYN_RECV;
 786         newsk->sk_backlog_rcv = pipe_do_rcv;
 787         newsk->sk_protocol = sk->sk_protocol;
 788         newsk->sk_destruct = pipe_destruct;
 789
 790         newpn = pep_sk(newsk);
 791         pn_skb_get_dst_sockaddr(skb, &dst);
 792         newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst);
 793         newpn->pn_sk.resource = pn->pn_sk.resource;
 794         skb_queue_head_init(&newpn->ctrlreq_queue);
 795         newpn->pipe_handle = pipe_handle;
 796         atomic_set(&newpn->tx_credits, 0);
 797         newpn->peer_type = peer_type;
 798         newpn->rx_credits = 0;
 799         newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL;
 800         newpn->init_enable = enabled;
 801         newpn->aligned = aligned;
 802
 803         BUG_ON(!skb_queue_empty(&newsk->sk_receive_queue));
 804         skb_queue_head(&newsk->sk_receive_queue, skb);
 805         if (!sock_flag(sk, SOCK_DEAD))
 806                 sk->sk_data_ready(sk, 0);
 807
 808         sk_acceptq_added(sk);
 809         sk_add_node(newsk, &pn->ackq);
 810         return 0;
 811 }
 812
 813 /* Listening sock must be locked */
 814 static struct sock *pep_find_pipe(const struct hlist_head *hlist,
 815                                         const struct sockaddr_pn *dst,
 816                                         u8 pipe_handle)
 817 {
 818         struct hlist_node *node;
 819         struct sock *sknode;
 820         u16 dobj = pn_sockaddr_get_object(dst);
 821
 822         sk_for_each(sknode, node, hlist) {
 823                 struct pep_sock *pnnode = pep_sk(sknode);
 824
 825                 /* Ports match, but addresses might not: */
 826                 if (pnnode->pn_sk.sobject != dobj)
 827                         continue;
 828                 if (pnnode->pipe_handle != pipe_handle)
 829                         continue;
 830                 if (sknode->sk_state == TCP_CLOSE_WAIT)
 831                         continue;
 832
 833                 sock_hold(sknode);
 834                 return sknode;
 835         }
 836         return NULL;
 837 }
 838
 839 /*
 840  * Deliver an skb to a listening sock.
 841  * Socket lock must be held.
 842  * We then queue the skb to the right connected sock (if any).
 843  */
 844 static int pep_do_rcv(struct sock *sk, struct sk_buff *skb)
 845 {
 846         struct pep_sock *pn = pep_sk(sk);
 847         struct sock *sknode;
 848         struct pnpipehdr *hdr;
 849         struct sockaddr_pn dst;
 850         int err = NET_RX_SUCCESS;
 851         u8 pipe_handle;
 852
 853         if (!pskb_may_pull(skb, sizeof(*hdr)))
 854                 goto drop;
 855
 856         hdr = pnp_hdr(skb);
 857         pipe_handle = hdr->pipe_handle;
 858         if (pipe_handle == PN_PIPE_INVALID_HANDLE)
 859                 goto drop;
 860
 861         pn_skb_get_dst_sockaddr(skb, &dst);
 862
 863         /* Look for an existing pipe handle */
 864         sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
 865         if (sknode)
 866                 return sk_receive_skb(sknode, skb, 1);
 867
 868         /* Look for a pipe handle pending accept */
 869         sknode = pep_find_pipe(&pn->ackq, &dst, pipe_handle);
 870         if (sknode) {
 871                 sock_put(sknode);
 872                 if (net_ratelimit())
 873                         printk(KERN_WARNING"Phonet unconnected PEP ignored");
 874                 err = NET_RX_DROP;
 875                 goto drop;
 876         }
 877
 878         switch (hdr->message_id) {
 879         case PNS_PEP_CONNECT_REQ:
 880                 err = pep_connreq_rcv(sk, skb);
 881                 break;
 882
 883 #ifdef CONFIG_PHONET_PIPECTRLR
 884         case PNS_PEP_CONNECT_RESP:
 885                 err = pep_connresp_rcv(sk, skb);
 886                 break;
 887 #endif
 888
 889         case PNS_PEP_DISCONNECT_REQ:
 890                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 891                 break;
 892
 893         case PNS_PEP_CTRL_REQ:
 894                 pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC);
 895                 break;
 896
 897         case PNS_PEP_RESET_REQ:
 898         case PNS_PEP_ENABLE_REQ:
 899         case PNS_PEP_DISABLE_REQ:
 900                 /* invalid handle is not even allowed here! */
 901         default:
 902                 err = NET_RX_DROP;
 903         }
 904 drop:
 905         kfree_skb(skb);
 906         return err;
 907 }
 908
 909 static int pipe_do_remove(struct sock *sk)
 910 {
 911         struct pep_sock *pn = pep_sk(sk);
 912         struct pnpipehdr *ph;
 913         struct sk_buff *skb;
 914
 915         skb = alloc_skb(MAX_PNPIPE_HEADER, GFP_KERNEL);
 916         if (!skb)
 917                 return -ENOMEM;
 918
 919         skb_reserve(skb, MAX_PNPIPE_HEADER);
 920         __skb_push(skb, sizeof(*ph));
 921         skb_reset_transport_header(skb);
 922         ph = pnp_hdr(skb);
 923         ph->utid = 0;
 924         ph->message_id = PNS_PIPE_REMOVE_REQ;
 925         ph->pipe_handle = pn->pipe_handle;
 926         ph->data[0] = PAD;
 927
 928         return pn_skb_send(sk, skb, &pipe_srv);
 929 }
 930
 931 /* associated socket ceases to exist */
 932 static void pep_sock_close(struct sock *sk, long timeout)
 933 {
 934         struct pep_sock *pn = pep_sk(sk);
 935         int ifindex = 0;
 936
 937         sock_hold(sk); /* keep a reference after sk_common_release() */
 938         sk_common_release(sk);
 939
 940         lock_sock(sk);
 941         if (sk->sk_state == TCP_LISTEN) {
 942                 /* Destroy the listen queue */
 943                 struct sock *sknode;
 944                 struct hlist_node *p, *n;
 945
 946                 sk_for_each_safe(sknode, p, n, &pn->ackq)
 947                         sk_del_node_init(sknode);
 948                 sk->sk_state = TCP_CLOSE;
 949         } else if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED))
 950                 /* Forcefully remove dangling Phonet pipe */
 951                 pipe_do_remove(sk);
 952
 953 #ifdef CONFIG_PHONET_PIPECTRLR
 954         if (pn->pipe_state != PIPE_IDLE) {
 955                 /* send pep disconnect request */
 956                 pipe_handler_send_req(sk,
 957                                 PNS_PEP_DISCONNECT_UTID, PNS_PEP_DISCONNECT_REQ,
 958                                 GFP_KERNEL);
 959
 960                 pn->pipe_state = PIPE_IDLE;
 961                 sk->sk_state = TCP_CLOSE;
 962         }
 963 #endif
 964
 965         ifindex = pn->ifindex;
 966         pn->ifindex = 0;
 967         release_sock(sk);
 968
 969         if (ifindex)
 970                 gprs_detach(sk);
 971         sock_put(sk);
 972 }
 973
 974 static int pep_wait_connreq(struct sock *sk, int noblock)
 975 {
 976         struct task_struct *tsk = current;
 977         struct pep_sock *pn = pep_sk(sk);
 978         long timeo = sock_rcvtimeo(sk, noblock);
 979
 980         for (;;) {
 981                 DEFINE_WAIT(wait);
 982
 983                 if (sk->sk_state != TCP_LISTEN)
 984                         return -EINVAL;
 985                 if (!hlist_empty(&pn->ackq))
 986                         break;
 987                 if (!timeo)
 988                         return -EWOULDBLOCK;
 989                 if (signal_pending(tsk))
 990                         return sock_intr_errno(timeo);
 991
 992                 prepare_to_wait_exclusive(sk_sleep(sk), &wait,
 993                                                 TASK_INTERRUPTIBLE);
 994                 release_sock(sk);
 995                 timeo = schedule_timeout(timeo);
 996                 lock_sock(sk);
 997                 finish_wait(sk_sleep(sk), &wait);
 998         }
 999
1000         return 0;
1001 }
1002
1003 static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp)
1004 {
1005         struct pep_sock *pn = pep_sk(sk);
1006         struct sock *newsk = NULL;
1007         struct sk_buff *oskb;
1008         int err;
1009
1010         lock_sock(sk);
1011         err = pep_wait_connreq(sk, flags & O_NONBLOCK);
1012         if (err)
1013                 goto out;
1014
1015         newsk = __sk_head(&pn->ackq);
1016
1017         oskb = skb_dequeue(&newsk->sk_receive_queue);
1018         err = pep_accept_conn(newsk, oskb);
1019         if (err) {
1020                 skb_queue_head(&newsk->sk_receive_queue, oskb);
1021                 newsk = NULL;
1022                 goto out;
1023         }
1024         kfree_skb(oskb);
1025
1026         sock_hold(sk);
1027         pep_sk(newsk)->listener = sk;
1028
1029         sock_hold(newsk);
1030         sk_del_node_init(newsk);
1031         sk_acceptq_removed(sk);
1032         sk_add_node(newsk, &pn->hlist);
1033         __sock_put(newsk);
1034
1035 out:
1036         release_sock(sk);
1037         *errp = err;
1038         return newsk;
1039 }
1040
1041 #ifdef CONFIG_PHONET_PIPECTRLR
1042 static int pep_sock_connect(struct sock *sk, struct sockaddr *addr, int len)
1043 {
1044         struct pep_sock *pn = pep_sk(sk);
1045         struct sockaddr_pn *spn =  (struct sockaddr_pn *)addr;
1046
1047         memcpy(&pn->remote_pep, spn, sizeof(struct sockaddr_pn));
1048
1049         return pipe_handler_send_req(sk,
1050                         PNS_PEP_CONNECT_UTID, PNS_PEP_CONNECT_REQ,
1051                         GFP_ATOMIC);
1052 }
1053 #endif
1054
1055 static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg)
1056 {
1057         struct pep_sock *pn = pep_sk(sk);
1058         int answ;
1059
1060         switch (cmd) {
1061         case SIOCINQ:
1062                 if (sk->sk_state == TCP_LISTEN)
1063                         return -EINVAL;
1064
1065                 lock_sock(sk);
1066                 if (sock_flag(sk, SOCK_URGINLINE) &&
1067                     !skb_queue_empty(&pn->ctrlreq_queue))
1068                         answ = skb_peek(&pn->ctrlreq_queue)->len;
1069                 else if (!skb_queue_empty(&sk->sk_receive_queue))
1070                         answ = skb_peek(&sk->sk_receive_queue)->len;
1071                 else
1072                         answ = 0;
1073                 release_sock(sk);
1074                 return put_user(answ, (int __user *)arg);
1075         }
1076
1077         return -ENOIOCTLCMD;
1078 }
1079
1080 static int pep_init(struct sock *sk)
1081 {
1082         struct pep_sock *pn = pep_sk(sk);
1083
1084         INIT_HLIST_HEAD(&pn->ackq);
1085         INIT_HLIST_HEAD(&pn->hlist);
1086         skb_queue_head_init(&pn->ctrlreq_queue);
1087         pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
1088         return 0;
1089 }
1090
1091 static int pep_setsockopt(struct sock *sk, int level, int optname,
1092                                 char __user *optval, unsigned int optlen)
1093 {
1094         struct pep_sock *pn = pep_sk(sk);
1095         int val = 0, err = 0;
1096
1097         if (level != SOL_PNPIPE)
1098                 return -ENOPROTOOPT;
1099         if (optlen >= sizeof(int)) {
1100                 if (get_user(val, (int __user *) optval))
1101                         return -EFAULT;
1102         }
1103
1104         lock_sock(sk);
1105         switch (optname) {
1106 #ifdef CONFIG_PHONET_PIPECTRLR
1107         case PNPIPE_PIPE_HANDLE:
1108                 if (val) {
1109                         if (pn->pipe_state > PIPE_IDLE) {
1110                                 err = -EFAULT;
1111                                 break;
1112                         }
1113                         pn->pipe_handle = val;
1114                         break;
1115                 }
1116 #endif
1117
1118         case PNPIPE_ENCAP:
1119                 if (val && val != PNPIPE_ENCAP_IP) {
1120                         err = -EINVAL;
1121                         break;
1122                 }
1123                 if (!pn->ifindex == !val)
1124                         break; /* Nothing to do! */
1125                 if (!capable(CAP_NET_ADMIN)) {
1126                         err = -EPERM;
1127                         break;
1128                 }
1129                 if (val) {
1130                         release_sock(sk);
1131                         err = gprs_attach(sk);
1132                         if (err > 0) {
1133                                 pn->ifindex = err;
1134                                 err = 0;
1135                         }
1136                 } else {
1137                         pn->ifindex = 0;
1138                         release_sock(sk);
1139                         gprs_detach(sk);
1140                         err = 0;
1141                 }
1142                 goto out_norel;
1143
1144 #ifdef CONFIG_PHONET_PIPECTRLR
1145         case PNPIPE_ENABLE:
1146                 if (pn->pipe_state <= PIPE_IDLE) {
1147                         err = -ENOTCONN;
1148                         break;
1149                 }
1150                 err = pipe_handler_enable_pipe(sk, val);
1151                 break;
1152 #endif
1153
1154         default:
1155                 err = -ENOPROTOOPT;
1156         }
1157         release_sock(sk);
1158
1159 out_norel:
1160         return err;
1161 }
1162
1163 static int pep_getsockopt(struct sock *sk, int level, int optname,
1164                                 char __user *optval, int __user *optlen)
1165 {
1166         struct pep_sock *pn = pep_sk(sk);
1167         int len, val;
1168
1169         if (level != SOL_PNPIPE)
1170                 return -ENOPROTOOPT;
1171         if (get_user(len, optlen))
1172                 return -EFAULT;
1173
1174         switch (optname) {
1175         case PNPIPE_ENCAP:
1176                 val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE;
1177                 break;
1178
1179         case PNPIPE_IFINDEX:
1180                 val = pn->ifindex;
1181                 break;
1182
1183 #ifdef CONFIG_PHONET_PIPECTRLR
1184         case PNPIPE_ENABLE:
1185                 if (pn->pipe_state <= PIPE_IDLE)
1186                         return -ENOTCONN;
1187                 val = pn->pipe_state != PIPE_DISABLED;
1188                 break;
1189 #endif
1190
1191         default:
1192                 return -ENOPROTOOPT;
1193         }
1194
1195         len = min_t(unsigned int, sizeof(int), len);
1196         if (put_user(len, optlen))
1197                 return -EFAULT;
1198         if (put_user(val, (int __user *) optval))
1199                 return -EFAULT;
1200         return 0;
1201 }
1202
1203 static int pipe_skb_send(struct sock *sk, struct sk_buff *skb)
1204 {
1205         struct pep_sock *pn = pep_sk(sk);
1206         struct pnpipehdr *ph;
1207         int err;
1208
1209         if (pn_flow_safe(pn->tx_fc) &&
1210             !atomic_add_unless(&pn->tx_credits, -1, 0)) {
1211                 kfree_skb(skb);
1212                 return -ENOBUFS;
1213         }
1214
1215         skb_push(skb, 3 + pn->aligned);
1216         skb_reset_transport_header(skb);
1217         ph = pnp_hdr(skb);
1218         ph->utid = 0;
1219         if (pn->aligned) {
1220                 ph->message_id = PNS_PIPE_ALIGNED_DATA;
1221                 ph->data[0] = 0; /* padding */
1222         } else
1223                 ph->message_id = PNS_PIPE_DATA;
1224         ph->pipe_handle = pn->pipe_handle;
1225 #ifdef CONFIG_PHONET_PIPECTRLR
1226         err = pn_skb_send(sk, skb, &pn->remote_pep);
1227 #else
1228         err = pn_skb_send(sk, skb, &pipe_srv);
1229 #endif
1230
1231         if (err && pn_flow_safe(pn->tx_fc))
1232                 atomic_inc(&pn->tx_credits);
1233         return err;
1234
1235 }
1236
1237 static int pep_sendmsg(struct kiocb *iocb, struct sock *sk,
1238                         struct msghdr *msg, size_t len)
1239 {
1240         struct pep_sock *pn = pep_sk(sk);
1241         struct sk_buff *skb;
1242         long timeo;
1243         int flags = msg->msg_flags;
1244         int err, done;
1245
1246         if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|
1247                                 MSG_CMSG_COMPAT)) ||
1248                         !(msg->msg_flags & MSG_EOR))
1249                 return -EOPNOTSUPP;
1250
1251         skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len,
1252                                         flags & MSG_DONTWAIT, &err);
1253         if (!skb)
1254                 return err;
1255
1256         skb_reserve(skb, MAX_PHONET_HEADER + 3);
1257         err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1258         if (err < 0)
1259                 goto outfree;
1260
1261         lock_sock(sk);
1262         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1263         if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) {
1264                 err = -ENOTCONN;
1265                 goto out;
1266         }
1267         if (sk->sk_state != TCP_ESTABLISHED) {
1268                 /* Wait until the pipe gets to enabled state */
1269 disabled:
1270                 err = sk_stream_wait_connect(sk, &timeo);
1271                 if (err)
1272                         goto out;
1273
1274                 if (sk->sk_state == TCP_CLOSE_WAIT) {
1275                         err = -ECONNRESET;
1276                         goto out;
1277                 }
1278         }
1279         BUG_ON(sk->sk_state != TCP_ESTABLISHED);
1280
1281         /* Wait until flow control allows TX */
1282         done = atomic_read(&pn->tx_credits);
1283         while (!done) {
1284                 DEFINE_WAIT(wait);
1285
1286                 if (!timeo) {
1287                         err = -EAGAIN;
1288                         goto out;
1289                 }
1290                 if (signal_pending(current)) {
1291                         err = sock_intr_errno(timeo);
1292                         goto out;
1293                 }
1294
1295                 prepare_to_wait(sk_sleep(sk), &wait,
1296                                 TASK_INTERRUPTIBLE);
1297                 done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits));
1298                 finish_wait(sk_sleep(sk), &wait);
1299
1300                 if (sk->sk_state != TCP_ESTABLISHED)
1301                         goto disabled;
1302         }
1303
1304         err = pipe_skb_send(sk, skb);
1305         if (err >= 0)
1306                 err = len; /* success! */
1307         skb = NULL;
1308 out:
1309         release_sock(sk);
1310 outfree:
1311         kfree_skb(skb);
1312         return err;
1313 }
1314
1315 int pep_writeable(struct sock *sk)
1316 {
1317         struct pep_sock *pn = pep_sk(sk);
1318
1319         return atomic_read(&pn->tx_credits);
1320 }
1321
1322 int pep_write(struct sock *sk, struct sk_buff *skb)
1323 {
1324         struct sk_buff *rskb, *fs;
1325         int flen = 0;
1326
1327         if (pep_sk(sk)->aligned)
1328                 return pipe_skb_send(sk, skb);
1329
1330         rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC);
1331         if (!rskb) {
1332                 kfree_skb(skb);
1333                 return -ENOMEM;
1334         }
1335         skb_shinfo(rskb)->frag_list = skb;
1336         rskb->len += skb->len;
1337         rskb->data_len += rskb->len;
1338         rskb->truesize += rskb->len;
1339
1340         /* Avoid nested fragments */
1341         skb_walk_frags(skb, fs)
1342                 flen += fs->len;
1343         skb->next = skb_shinfo(skb)->frag_list;
1344         skb_frag_list_init(skb);
1345         skb->len -= flen;
1346         skb->data_len -= flen;
1347         skb->truesize -= flen;
1348
1349         skb_reserve(rskb, MAX_PHONET_HEADER + 3);
1350         return pipe_skb_send(sk, rskb);
1351 }
1352
1353 struct sk_buff *pep_read(struct sock *sk)
1354 {
1355         struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue);
1356
1357         if (sk->sk_state == TCP_ESTABLISHED)
1358                 pipe_grant_credits(sk);
1359         return skb;
1360 }
1361
1362 static int pep_recvmsg(struct kiocb *iocb, struct sock *sk,
1363                         struct msghdr *msg, size_t len, int noblock,
1364                         int flags, int *addr_len)
1365 {
1366         struct sk_buff *skb;
1367         int err;
1368
1369         if (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL|
1370                         MSG_NOSIGNAL|MSG_CMSG_COMPAT))
1371                 return -EOPNOTSUPP;
1372
1373         if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE)))
1374                 return -ENOTCONN;
1375
1376         if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) {
1377                 /* Dequeue and acknowledge control request */
1378                 struct pep_sock *pn = pep_sk(sk);
1379
1380                 if (flags & MSG_PEEK)
1381                         return -EOPNOTSUPP;
1382                 skb = skb_dequeue(&pn->ctrlreq_queue);
1383                 if (skb) {
1384                         pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR,
1385                                                 GFP_KERNEL);
1386                         msg->msg_flags |= MSG_OOB;
1387                         goto copy;
1388                 }
1389                 if (flags & MSG_OOB)
1390                         return -EINVAL;
1391         }
1392
1393         skb = skb_recv_datagram(sk, flags, noblock, &err);
1394         lock_sock(sk);
1395         if (skb == NULL) {
1396                 if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT)
1397                         err = -ECONNRESET;
1398                 release_sock(sk);
1399                 return err;
1400         }
1401
1402         if (sk->sk_state == TCP_ESTABLISHED)
1403                 pipe_grant_credits(sk);
1404         release_sock(sk);
1405 copy:
1406         msg->msg_flags |= MSG_EOR;
1407         if (skb->len > len)
1408                 msg->msg_flags |= MSG_TRUNC;
1409         else
1410                 len = skb->len;
1411
1412         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len);
1413         if (!err)
1414                 err = (flags & MSG_TRUNC) ? skb->len : len;
1415
1416         skb_free_datagram(sk, skb);
1417         return err;
1418 }
1419
1420 static void pep_sock_unhash(struct sock *sk)
1421 {
1422         struct pep_sock *pn = pep_sk(sk);
1423         struct sock *skparent = NULL;
1424
1425         lock_sock(sk);
1426
1427 #ifndef CONFIG_PHONET_PIPECTRLR
1428         if ((1 << sk->sk_state) & ~(TCPF_CLOSE|TCPF_LISTEN)) {
1429                 skparent = pn->listener;
1430                 release_sock(sk);
1431
1432                 pn = pep_sk(skparent);
1433                 lock_sock(skparent);
1434                 sk_del_node_init(sk);
1435                 sk = skparent;
1436         }
1437 #endif
1438         /* Unhash a listening sock only when it is closed
1439          * and all of its active connected pipes are closed. */
1440         if (hlist_empty(&pn->hlist))
1441                 pn_sock_unhash(&pn->pn_sk.sk);
1442         release_sock(sk);
1443
1444         if (skparent)
1445                 sock_put(skparent);
1446 }
1447
1448 static struct proto pep_proto = {
1449         .close          = pep_sock_close,
1450         .accept         = pep_sock_accept,
1451 #ifdef CONFIG_PHONET_PIPECTRLR
1452         .connect        = pep_sock_connect,
1453 #endif
1454         .ioctl          = pep_ioctl,
1455         .init           = pep_init,
1456         .setsockopt     = pep_setsockopt,
1457         .getsockopt     = pep_getsockopt,
1458         .sendmsg        = pep_sendmsg,
1459         .recvmsg        = pep_recvmsg,
1460         .backlog_rcv    = pep_do_rcv,
1461         .hash           = pn_sock_hash,
1462         .unhash         = pep_sock_unhash,
1463         .get_port       = pn_sock_get_port,
1464         .obj_size       = sizeof(struct pep_sock),
1465         .owner          = THIS_MODULE,
1466         .name           = "PNPIPE",
1467 };
1468
1469 static struct phonet_protocol pep_pn_proto = {
1470         .ops            = &phonet_stream_ops,
1471         .prot           = &pep_proto,
1472         .sock_type      = SOCK_SEQPACKET,
1473 };
1474
1475 static int __init pep_register(void)
1476 {
1477         return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto);
1478 }
1479
1480 static void __exit pep_unregister(void)
1481 {
1482         phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto);
1483 }
1484
1485 module_init(pep_register);
1486 module_exit(pep_unregister);
1487 MODULE_AUTHOR("Remi Denis-Courmont, Nokia");
1488 MODULE_DESCRIPTION("Phonet pipe protocol");
1489 MODULE_LICENSE("GPL");
1490 MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE);