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         struct pep_sock *pn = pep_sk(sk);
 304         int utid, req;
 305
 306         if (enable) {
 307                 utid = PNS_PIPE_ENABLE_UTID;
 308                 req = PNS_PEP_ENABLE_REQ;
 309         } else {
 310                 utid = PNS_PIPE_DISABLE_UTID;
 311                 req = PNS_PEP_DISABLE_REQ;
 312         }
 313         return pipe_handler_send_req(sk, utid, req, GFP_ATOMIC);
 314 }
 315 #endif
 316
 317 static int pep_accept_conn(struct sock *sk, struct sk_buff *skb)
 318 {
 319         static const u8 data[20] = {
 320                 PAD, PAD, PAD, 2 /* sub-blocks */,
 321                 PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD,
 322                         PN_MULTI_CREDIT_FLOW_CONTROL,
 323                         PN_ONE_CREDIT_FLOW_CONTROL,
 324                         PN_LEGACY_FLOW_CONTROL,
 325                         PAD,
 326                 PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD,
 327                         PN_MULTI_CREDIT_FLOW_CONTROL,
 328                         PN_ONE_CREDIT_FLOW_CONTROL,
 329                         PN_LEGACY_FLOW_CONTROL,
 330                         PAD,
 331         };
 332
 333         might_sleep();
 334         return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data),
 335                                 GFP_KERNEL);
 336 }
 337
 338 static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code)
 339 {
 340         static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ };
 341         WARN_ON(code == PN_PIPE_NO_ERROR);
 342         return pep_reply(sk, skb, code, data, sizeof(data), GFP_ATOMIC);
 343 }
 344
 345 /* Control requests are not sent by the pipe service and have a specific
 346  * message format. */
 347 static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code,
 348                                 gfp_t priority)
 349 {
 350         const struct pnpipehdr *oph = pnp_hdr(oskb);
 351         struct sk_buff *skb;
 352         struct pnpipehdr *ph;
 353         struct sockaddr_pn dst;
 354
 355         skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority);
 356         if (!skb)
 357                 return -ENOMEM;
 358         skb_set_owner_w(skb, sk);
 359
 360         skb_reserve(skb, MAX_PHONET_HEADER);
 361         ph = (struct pnpipehdr *)skb_put(skb, sizeof(*ph) + 4);
 362
 363         ph->utid = oph->utid;
 364         ph->message_id = PNS_PEP_CTRL_RESP;
 365         ph->pipe_handle = oph->pipe_handle;
 366         ph->data[0] = oph->data[1]; /* CTRL id */
 367         ph->data[1] = oph->data[0]; /* PEP type */
 368         ph->data[2] = code; /* error code, at an usual offset */
 369         ph->data[3] = PAD;
 370         ph->data[4] = PAD;
 371
 372         pn_skb_get_src_sockaddr(oskb, &dst);
 373         return pn_skb_send(sk, skb, &dst);
 374 }
 375
 376 static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority)
 377 {
 378         struct pep_sock *pn = pep_sk(sk);
 379         struct pnpipehdr *ph;
 380         struct sk_buff *skb;
 381
 382         skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority);
 383         if (!skb)
 384                 return -ENOMEM;
 385         skb_set_owner_w(skb, sk);
 386
 387         skb_reserve(skb, MAX_PNPIPE_HEADER + 4);
 388         __skb_push(skb, sizeof(*ph) + 4);
 389         skb_reset_transport_header(skb);
 390         ph = pnp_hdr(skb);
 391         ph->utid = 0;
 392         ph->message_id = PNS_PEP_STATUS_IND;
 393         ph->pipe_handle = pn->pipe_handle;
 394         ph->pep_type = PN_PEP_TYPE_COMMON;
 395         ph->data[1] = type;
 396         ph->data[2] = PAD;
 397         ph->data[3] = PAD;
 398         ph->data[4] = status;
 399
 400 #ifdef CONFIG_PHONET_PIPECTRLR
 401         return pn_skb_send(sk, skb, &pn->remote_pep);
 402 #else
 403         return pn_skb_send(sk, skb, &pipe_srv);
 404 #endif
 405 }
 406
 407 /* Send our RX flow control information to the sender.
 408  * Socket must be locked. */
 409 static void pipe_grant_credits(struct sock *sk)
 410 {
 411         struct pep_sock *pn = pep_sk(sk);
 412
 413         BUG_ON(sk->sk_state != TCP_ESTABLISHED);
 414
 415         switch (pn->rx_fc) {
 416         case PN_LEGACY_FLOW_CONTROL: /* TODO */
 417                 break;
 418         case PN_ONE_CREDIT_FLOW_CONTROL:
 419                 pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL,
 420                                 PEP_IND_READY, GFP_ATOMIC);
 421                 pn->rx_credits = 1;
 422                 break;
 423         case PN_MULTI_CREDIT_FLOW_CONTROL:
 424                 if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX)
 425                         break;
 426                 if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS,
 427                                         CREDITS_MAX - pn->rx_credits,
 428                                         GFP_ATOMIC) == 0)
 429                         pn->rx_credits = CREDITS_MAX;
 430                 break;
 431         }
 432 }
 433
 434 static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb)
 435 {
 436         struct pep_sock *pn = pep_sk(sk);
 437         struct pnpipehdr *hdr;
 438         int wake = 0;
 439
 440         if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
 441                 return -EINVAL;
 442
 443         hdr = pnp_hdr(skb);
 444         if (hdr->data[0] != PN_PEP_TYPE_COMMON) {
 445                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP type: %u\n",
 446                                 (unsigned)hdr->data[0]);
 447                 return -EOPNOTSUPP;
 448         }
 449
 450         switch (hdr->data[1]) {
 451         case PN_PEP_IND_FLOW_CONTROL:
 452                 switch (pn->tx_fc) {
 453                 case PN_LEGACY_FLOW_CONTROL:
 454                         switch (hdr->data[4]) {
 455                         case PEP_IND_BUSY:
 456                                 atomic_set(&pn->tx_credits, 0);
 457                                 break;
 458                         case PEP_IND_READY:
 459                                 atomic_set(&pn->tx_credits, wake = 1);
 460                                 break;
 461                         }
 462                         break;
 463                 case PN_ONE_CREDIT_FLOW_CONTROL:
 464                         if (hdr->data[4] == PEP_IND_READY)
 465                                 atomic_set(&pn->tx_credits, wake = 1);
 466                         break;
 467                 }
 468                 break;
 469
 470         case PN_PEP_IND_ID_MCFC_GRANT_CREDITS:
 471                 if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL)
 472                         break;
 473                 atomic_add(wake = hdr->data[4], &pn->tx_credits);
 474                 break;
 475
 476         default:
 477                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP indication: %u\n",
 478                                 (unsigned)hdr->data[1]);
 479                 return -EOPNOTSUPP;
 480         }
 481         if (wake)
 482                 sk->sk_write_space(sk);
 483         return 0;
 484 }
 485
 486 static int pipe_rcv_created(struct sock *sk, struct sk_buff *skb)
 487 {
 488         struct pep_sock *pn = pep_sk(sk);
 489         struct pnpipehdr *hdr = pnp_hdr(skb);
 490         u8 n_sb = hdr->data[0];
 491
 492         pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
 493         __skb_pull(skb, sizeof(*hdr));
 494         while (n_sb > 0) {
 495                 u8 type, buf[2], len = sizeof(buf);
 496                 u8 *data = pep_get_sb(skb, &type, &len, buf);
 497
 498                 if (data == NULL)
 499                         return -EINVAL;
 500                 switch (type) {
 501                 case PN_PIPE_SB_NEGOTIATED_FC:
 502                         if (len < 2 || (data[0] | data[1]) > 3)
 503                                 break;
 504                         pn->tx_fc = data[0] & 3;
 505                         pn->rx_fc = data[1] & 3;
 506                         break;
 507                 }
 508                 n_sb--;
 509         }
 510         return 0;
 511 }
 512
 513 /* Queue an skb to a connected sock.
 514  * Socket lock must be held. */
 515 static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
 516 {
 517         struct pep_sock *pn = pep_sk(sk);
 518         struct pnpipehdr *hdr = pnp_hdr(skb);
 519         struct sk_buff_head *queue;
 520         int err = 0;
 521
 522         BUG_ON(sk->sk_state == TCP_CLOSE_WAIT);
 523
 524         switch (hdr->message_id) {
 525         case PNS_PEP_CONNECT_REQ:
 526                 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE);
 527                 break;
 528
 529         case PNS_PEP_DISCONNECT_REQ:
 530                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 531                 sk->sk_state = TCP_CLOSE_WAIT;
 532                 if (!sock_flag(sk, SOCK_DEAD))
 533                         sk->sk_state_change(sk);
 534                 break;
 535
 536 #ifdef CONFIG_PHONET_PIPECTRLR
 537         case PNS_PEP_DISCONNECT_RESP:
 538                 pn->pipe_state = PIPE_IDLE;
 539                 sk->sk_state = TCP_CLOSE;
 540                 break;
 541 #endif
 542
 543         case PNS_PEP_ENABLE_REQ:
 544                 /* Wait for PNS_PIPE_(ENABLED|REDIRECTED)_IND */
 545                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 546                 break;
 547
 548 #ifdef CONFIG_PHONET_PIPECTRLR
 549         case PNS_PEP_ENABLE_RESP:
 550                 pn->pipe_state = PIPE_ENABLED;
 551                 pipe_handler_send_ind(sk, PNS_PIPE_ENABLED_IND_UTID,
 552                                 PNS_PIPE_ENABLED_IND);
 553
 554                 if (!pn_flow_safe(pn->tx_fc)) {
 555                         atomic_set(&pn->tx_credits, 1);
 556                         sk->sk_write_space(sk);
 557                 }
 558                 if (sk->sk_state == TCP_ESTABLISHED)
 559                         break; /* Nothing to do */
 560                 sk->sk_state = TCP_ESTABLISHED;
 561                 pipe_grant_credits(sk);
 562                 break;
 563 #endif
 564
 565         case PNS_PEP_RESET_REQ:
 566                 switch (hdr->state_after_reset) {
 567                 case PN_PIPE_DISABLE:
 568                         pn->init_enable = 0;
 569                         break;
 570                 case PN_PIPE_ENABLE:
 571                         pn->init_enable = 1;
 572                         break;
 573                 default: /* not allowed to send an error here!? */
 574                         err = -EINVAL;
 575                         goto out;
 576                 }
 577                 /* fall through */
 578         case PNS_PEP_DISABLE_REQ:
 579                 atomic_set(&pn->tx_credits, 0);
 580                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 581                 break;
 582
 583 #ifdef CONFIG_PHONET_PIPECTRLR
 584         case PNS_PEP_DISABLE_RESP:
 585                 pn->pipe_state = PIPE_DISABLED;
 586                 atomic_set(&pn->tx_credits, 0);
 587                 pipe_handler_send_ind(sk, PNS_PIPE_DISABLED_IND_UTID,
 588                                 PNS_PIPE_DISABLED_IND);
 589                 sk->sk_state = TCP_SYN_RECV;
 590                 pn->rx_credits = 0;
 591                 break;
 592 #endif
 593
 594         case PNS_PEP_CTRL_REQ:
 595                 if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) {
 596                         atomic_inc(&sk->sk_drops);
 597                         break;
 598                 }
 599                 __skb_pull(skb, 4);
 600                 queue = &pn->ctrlreq_queue;
 601                 goto queue;
 602
 603         case PNS_PIPE_ALIGNED_DATA:
 604                 __skb_pull(skb, 1);
 605                 /* fall through */
 606         case PNS_PIPE_DATA:
 607                 __skb_pull(skb, 3); /* Pipe data header */
 608                 if (!pn_flow_safe(pn->rx_fc)) {
 609                         err = sock_queue_rcv_skb(sk, skb);
 610                         if (!err)
 611                                 return 0;
 612                         break;
 613                 }
 614
 615                 if (pn->rx_credits == 0) {
 616                         atomic_inc(&sk->sk_drops);
 617                         err = -ENOBUFS;
 618                         break;
 619                 }
 620                 pn->rx_credits--;
 621                 queue = &sk->sk_receive_queue;
 622                 goto queue;
 623
 624         case PNS_PEP_STATUS_IND:
 625                 pipe_rcv_status(sk, skb);
 626                 break;
 627
 628         case PNS_PIPE_REDIRECTED_IND:
 629                 err = pipe_rcv_created(sk, skb);
 630                 break;
 631
 632         case PNS_PIPE_CREATED_IND:
 633                 err = pipe_rcv_created(sk, skb);
 634                 if (err)
 635                         break;
 636                 /* fall through */
 637         case PNS_PIPE_RESET_IND:
 638                 if (!pn->init_enable)
 639                         break;
 640                 /* fall through */
 641         case PNS_PIPE_ENABLED_IND:
 642                 if (!pn_flow_safe(pn->tx_fc)) {
 643                         atomic_set(&pn->tx_credits, 1);
 644                         sk->sk_write_space(sk);
 645                 }
 646                 if (sk->sk_state == TCP_ESTABLISHED)
 647                         break; /* Nothing to do */
 648                 sk->sk_state = TCP_ESTABLISHED;
 649                 pipe_grant_credits(sk);
 650                 break;
 651
 652         case PNS_PIPE_DISABLED_IND:
 653                 sk->sk_state = TCP_SYN_RECV;
 654                 pn->rx_credits = 0;
 655                 break;
 656
 657         default:
 658                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP message: %u\n",
 659                                 hdr->message_id);
 660                 err = -EINVAL;
 661         }
 662 out:
 663         kfree_skb(skb);
 664         return err;
 665
 666 queue:
 667         skb->dev = NULL;
 668         skb_set_owner_r(skb, sk);
 669         err = skb->len;
 670         skb_queue_tail(queue, skb);
 671         if (!sock_flag(sk, SOCK_DEAD))
 672                 sk->sk_data_ready(sk, err);
 673         return 0;
 674 }
 675
 676 /* Destroy connected sock. */
 677 static void pipe_destruct(struct sock *sk)
 678 {
 679         struct pep_sock *pn = pep_sk(sk);
 680
 681         skb_queue_purge(&sk->sk_receive_queue);
 682         skb_queue_purge(&pn->ctrlreq_queue);
 683 }
 684
 685 #ifdef CONFIG_PHONET_PIPECTRLR
 686 static int pep_connresp_rcv(struct sock *sk, struct sk_buff *skb)
 687 {
 688         struct pep_sock *pn = pep_sk(sk);
 689         u8 host_pref_rx_fc[3] = {3, 2, 1}, host_req_tx_fc[3] = {3, 2, 1};
 690         u8 remote_pref_rx_fc[3], remote_req_tx_fc[3];
 691         u8 negotiated_rx_fc, negotiated_tx_fc;
 692         int ret;
 693
 694         pipe_get_flow_info(sk, skb, remote_pref_rx_fc,
 695                         remote_req_tx_fc);
 696         negotiated_tx_fc = pipe_negotiate_fc(remote_req_tx_fc,
 697                         host_pref_rx_fc,
 698                         sizeof(host_pref_rx_fc));
 699         negotiated_rx_fc = pipe_negotiate_fc(host_req_tx_fc,
 700                         remote_pref_rx_fc,
 701                         sizeof(host_pref_rx_fc));
 702
 703         pn->pipe_state = PIPE_DISABLED;
 704         sk->sk_state = TCP_SYN_RECV;
 705         sk->sk_backlog_rcv = pipe_do_rcv;
 706         sk->sk_destruct = pipe_destruct;
 707         pn->rx_credits = 0;
 708         pn->rx_fc = negotiated_rx_fc;
 709         pn->tx_fc = negotiated_tx_fc;
 710         sk->sk_state_change(sk);
 711
 712         ret = pipe_handler_send_created_ind(sk,
 713                         PNS_PIPE_CREATED_IND_UTID,
 714                         PNS_PIPE_CREATED_IND
 715                         );
 716
 717         return ret;
 718 }
 719 #endif
 720
 721 static int pep_connreq_rcv(struct sock *sk, struct sk_buff *skb)
 722 {
 723         struct sock *newsk;
 724         struct pep_sock *newpn, *pn = pep_sk(sk);
 725         struct pnpipehdr *hdr;
 726         struct sockaddr_pn dst;
 727         u16 peer_type;
 728         u8 pipe_handle, enabled, n_sb;
 729         u8 aligned = 0;
 730
 731         if (!pskb_pull(skb, sizeof(*hdr) + 4))
 732                 return -EINVAL;
 733
 734         hdr = pnp_hdr(skb);
 735         pipe_handle = hdr->pipe_handle;
 736         switch (hdr->state_after_connect) {
 737         case PN_PIPE_DISABLE:
 738                 enabled = 0;
 739                 break;
 740         case PN_PIPE_ENABLE:
 741                 enabled = 1;
 742                 break;
 743         default:
 744                 pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM);
 745                 return -EINVAL;
 746         }
 747         peer_type = hdr->other_pep_type << 8;
 748
 749         if (unlikely(sk->sk_state != TCP_LISTEN) || sk_acceptq_is_full(sk)) {
 750                 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE);
 751                 return -ENOBUFS;
 752         }
 753
 754         /* Parse sub-blocks (options) */
 755         n_sb = hdr->data[4];
 756         while (n_sb > 0) {
 757                 u8 type, buf[1], len = sizeof(buf);
 758                 const u8 *data = pep_get_sb(skb, &type, &len, buf);
 759
 760                 if (data == NULL)
 761                         return -EINVAL;
 762                 switch (type) {
 763                 case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE:
 764                         if (len < 1)
 765                                 return -EINVAL;
 766                         peer_type = (peer_type & 0xff00) | data[0];
 767                         break;
 768                 case PN_PIPE_SB_ALIGNED_DATA:
 769                         aligned = data[0] != 0;
 770                         break;
 771                 }
 772                 n_sb--;
 773         }
 774
 775         skb = skb_clone(skb, GFP_ATOMIC);
 776         if (!skb)
 777                 return -ENOMEM;
 778
 779         /* Create a new to-be-accepted sock */
 780         newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_ATOMIC, sk->sk_prot);
 781         if (!newsk) {
 782                 kfree_skb(skb);
 783                 return -ENOMEM;
 784         }
 785         sock_init_data(NULL, newsk);
 786         newsk->sk_state = TCP_SYN_RECV;
 787         newsk->sk_backlog_rcv = pipe_do_rcv;
 788         newsk->sk_protocol = sk->sk_protocol;
 789         newsk->sk_destruct = pipe_destruct;
 790
 791         newpn = pep_sk(newsk);
 792         pn_skb_get_dst_sockaddr(skb, &dst);
 793         newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst);
 794         newpn->pn_sk.resource = pn->pn_sk.resource;
 795         skb_queue_head_init(&newpn->ctrlreq_queue);
 796         newpn->pipe_handle = pipe_handle;
 797         atomic_set(&newpn->tx_credits, 0);
 798         newpn->peer_type = peer_type;
 799         newpn->rx_credits = 0;
 800         newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL;
 801         newpn->init_enable = enabled;
 802         newpn->aligned = aligned;
 803
 804         BUG_ON(!skb_queue_empty(&newsk->sk_receive_queue));
 805         skb_queue_head(&newsk->sk_receive_queue, skb);
 806         if (!sock_flag(sk, SOCK_DEAD))
 807                 sk->sk_data_ready(sk, 0);
 808
 809         sk_acceptq_added(sk);
 810         sk_add_node(newsk, &pn->ackq);
 811         return 0;
 812 }
 813
 814 /* Listening sock must be locked */
 815 static struct sock *pep_find_pipe(const struct hlist_head *hlist,
 816                                         const struct sockaddr_pn *dst,
 817                                         u8 pipe_handle)
 818 {
 819         struct hlist_node *node;
 820         struct sock *sknode;
 821         u16 dobj = pn_sockaddr_get_object(dst);
 822
 823         sk_for_each(sknode, node, hlist) {
 824                 struct pep_sock *pnnode = pep_sk(sknode);
 825
 826                 /* Ports match, but addresses might not: */
 827                 if (pnnode->pn_sk.sobject != dobj)
 828                         continue;
 829                 if (pnnode->pipe_handle != pipe_handle)
 830                         continue;
 831                 if (sknode->sk_state == TCP_CLOSE_WAIT)
 832                         continue;
 833
 834                 sock_hold(sknode);
 835                 return sknode;
 836         }
 837         return NULL;
 838 }
 839
 840 /*
 841  * Deliver an skb to a listening sock.
 842  * Socket lock must be held.
 843  * We then queue the skb to the right connected sock (if any).
 844  */
 845 static int pep_do_rcv(struct sock *sk, struct sk_buff *skb)
 846 {
 847         struct pep_sock *pn = pep_sk(sk);
 848         struct sock *sknode;
 849         struct pnpipehdr *hdr;
 850         struct sockaddr_pn dst;
 851         int err = NET_RX_SUCCESS;
 852         u8 pipe_handle;
 853
 854         if (!pskb_may_pull(skb, sizeof(*hdr)))
 855                 goto drop;
 856
 857         hdr = pnp_hdr(skb);
 858         pipe_handle = hdr->pipe_handle;
 859         if (pipe_handle == PN_PIPE_INVALID_HANDLE)
 860                 goto drop;
 861
 862         pn_skb_get_dst_sockaddr(skb, &dst);
 863
 864         /* Look for an existing pipe handle */
 865         sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
 866         if (sknode)
 867                 return sk_receive_skb(sknode, skb, 1);
 868
 869         /* Look for a pipe handle pending accept */
 870         sknode = pep_find_pipe(&pn->ackq, &dst, pipe_handle);
 871         if (sknode) {
 872                 sock_put(sknode);
 873                 if (net_ratelimit())
 874                         printk(KERN_WARNING"Phonet unconnected PEP ignored");
 875                 err = NET_RX_DROP;
 876                 goto drop;
 877         }
 878
 879         switch (hdr->message_id) {
 880         case PNS_PEP_CONNECT_REQ:
 881                 err = pep_connreq_rcv(sk, skb);
 882                 break;
 883
 884 #ifdef CONFIG_PHONET_PIPECTRLR
 885         case PNS_PEP_CONNECT_RESP:
 886                 err = pep_connresp_rcv(sk, skb);
 887                 break;
 888 #endif
 889
 890         case PNS_PEP_DISCONNECT_REQ:
 891                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
 892                 break;
 893
 894         case PNS_PEP_CTRL_REQ:
 895                 pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC);
 896                 break;
 897
 898         case PNS_PEP_RESET_REQ:
 899         case PNS_PEP_ENABLE_REQ:
 900         case PNS_PEP_DISABLE_REQ:
 901                 /* invalid handle is not even allowed here! */
 902         default:
 903                 err = NET_RX_DROP;
 904         }
 905 drop:
 906         kfree_skb(skb);
 907         return err;
 908 }
 909
 910 static int pipe_do_remove(struct sock *sk)
 911 {
 912         struct pep_sock *pn = pep_sk(sk);
 913         struct pnpipehdr *ph;
 914         struct sk_buff *skb;
 915
 916         skb = alloc_skb(MAX_PNPIPE_HEADER, GFP_KERNEL);
 917         if (!skb)
 918                 return -ENOMEM;
 919
 920         skb_reserve(skb, MAX_PNPIPE_HEADER);
 921         __skb_push(skb, sizeof(*ph));
 922         skb_reset_transport_header(skb);
 923         ph = pnp_hdr(skb);
 924         ph->utid = 0;
 925         ph->message_id = PNS_PIPE_REMOVE_REQ;
 926         ph->pipe_handle = pn->pipe_handle;
 927         ph->data[0] = PAD;
 928
 929         return pn_skb_send(sk, skb, &pipe_srv);
 930 }
 931
 932 /* associated socket ceases to exist */
 933 static void pep_sock_close(struct sock *sk, long timeout)
 934 {
 935         struct pep_sock *pn = pep_sk(sk);
 936         int ifindex = 0;
 937
 938         sock_hold(sk); /* keep a reference after sk_common_release() */
 939         sk_common_release(sk);
 940
 941         lock_sock(sk);
 942         if (sk->sk_state == TCP_LISTEN) {
 943                 /* Destroy the listen queue */
 944                 struct sock *sknode;
 945                 struct hlist_node *p, *n;
 946
 947                 sk_for_each_safe(sknode, p, n, &pn->ackq)
 948                         sk_del_node_init(sknode);
 949                 sk->sk_state = TCP_CLOSE;
 950         } else if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED))
 951                 /* Forcefully remove dangling Phonet pipe */
 952                 pipe_do_remove(sk);
 953
 954 #ifdef CONFIG_PHONET_PIPECTRLR
 955         if (pn->pipe_state != PIPE_IDLE) {
 956                 /* send pep disconnect request */
 957                 pipe_handler_send_req(sk,
 958                                 PNS_PEP_DISCONNECT_UTID, PNS_PEP_DISCONNECT_REQ,
 959                                 GFP_KERNEL);
 960
 961                 pn->pipe_state = PIPE_IDLE;
 962                 sk->sk_state = TCP_CLOSE;
 963         }
 964 #endif
 965
 966         ifindex = pn->ifindex;
 967         pn->ifindex = 0;
 968         release_sock(sk);
 969
 970         if (ifindex)
 971                 gprs_detach(sk);
 972         sock_put(sk);
 973 }
 974
 975 static int pep_wait_connreq(struct sock *sk, int noblock)
 976 {
 977         struct task_struct *tsk = current;
 978         struct pep_sock *pn = pep_sk(sk);
 979         long timeo = sock_rcvtimeo(sk, noblock);
 980
 981         for (;;) {
 982                 DEFINE_WAIT(wait);
 983
 984                 if (sk->sk_state != TCP_LISTEN)
 985                         return -EINVAL;
 986                 if (!hlist_empty(&pn->ackq))
 987                         break;
 988                 if (!timeo)
 989                         return -EWOULDBLOCK;
 990                 if (signal_pending(tsk))
 991                         return sock_intr_errno(timeo);
 992
 993                 prepare_to_wait_exclusive(sk_sleep(sk), &wait,
 994                                                 TASK_INTERRUPTIBLE);
 995                 release_sock(sk);
 996                 timeo = schedule_timeout(timeo);
 997                 lock_sock(sk);
 998                 finish_wait(sk_sleep(sk), &wait);
 999         }
1000
1001         return 0;
1002 }
1003
1004 static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp)
1005 {
1006         struct pep_sock *pn = pep_sk(sk);
1007         struct sock *newsk = NULL;
1008         struct sk_buff *oskb;
1009         int err;
1010
1011         lock_sock(sk);
1012         err = pep_wait_connreq(sk, flags & O_NONBLOCK);
1013         if (err)
1014                 goto out;
1015
1016         newsk = __sk_head(&pn->ackq);
1017
1018         oskb = skb_dequeue(&newsk->sk_receive_queue);
1019         err = pep_accept_conn(newsk, oskb);
1020         if (err) {
1021                 skb_queue_head(&newsk->sk_receive_queue, oskb);
1022                 newsk = NULL;
1023                 goto out;
1024         }
1025         kfree_skb(oskb);
1026
1027         sock_hold(sk);
1028         pep_sk(newsk)->listener = sk;
1029
1030         sock_hold(newsk);
1031         sk_del_node_init(newsk);
1032         sk_acceptq_removed(sk);
1033         sk_add_node(newsk, &pn->hlist);
1034         __sock_put(newsk);
1035
1036 out:
1037         release_sock(sk);
1038         *errp = err;
1039         return newsk;
1040 }
1041
1042 #ifdef CONFIG_PHONET_PIPECTRLR
1043 static int pep_sock_connect(struct sock *sk, struct sockaddr *addr, int len)
1044 {
1045         struct pep_sock *pn = pep_sk(sk);
1046         struct sockaddr_pn *spn =  (struct sockaddr_pn *)addr;
1047
1048         memcpy(&pn->remote_pep, spn, sizeof(struct sockaddr_pn));
1049
1050         return pipe_handler_send_req(sk,
1051                         PNS_PEP_CONNECT_UTID, PNS_PEP_CONNECT_REQ,
1052                         GFP_ATOMIC);
1053 }
1054 #endif
1055
1056 static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg)
1057 {
1058         struct pep_sock *pn = pep_sk(sk);
1059         int answ;
1060
1061         switch (cmd) {
1062         case SIOCINQ:
1063                 if (sk->sk_state == TCP_LISTEN)
1064                         return -EINVAL;
1065
1066                 lock_sock(sk);
1067                 if (sock_flag(sk, SOCK_URGINLINE) &&
1068                     !skb_queue_empty(&pn->ctrlreq_queue))
1069                         answ = skb_peek(&pn->ctrlreq_queue)->len;
1070                 else if (!skb_queue_empty(&sk->sk_receive_queue))
1071                         answ = skb_peek(&sk->sk_receive_queue)->len;
1072                 else
1073                         answ = 0;
1074                 release_sock(sk);
1075                 return put_user(answ, (int __user *)arg);
1076         }
1077
1078         return -ENOIOCTLCMD;
1079 }
1080
1081 static int pep_init(struct sock *sk)
1082 {
1083         struct pep_sock *pn = pep_sk(sk);
1084
1085         INIT_HLIST_HEAD(&pn->ackq);
1086         INIT_HLIST_HEAD(&pn->hlist);
1087         skb_queue_head_init(&pn->ctrlreq_queue);
1088         pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
1089         return 0;
1090 }
1091
1092 static int pep_setsockopt(struct sock *sk, int level, int optname,
1093                                 char __user *optval, unsigned int optlen)
1094 {
1095         struct pep_sock *pn = pep_sk(sk);
1096         int val = 0, err = 0;
1097
1098         if (level != SOL_PNPIPE)
1099                 return -ENOPROTOOPT;
1100         if (optlen >= sizeof(int)) {
1101                 if (get_user(val, (int __user *) optval))
1102                         return -EFAULT;
1103         }
1104
1105         lock_sock(sk);
1106         switch (optname) {
1107 #ifdef CONFIG_PHONET_PIPECTRLR
1108         case PNPIPE_PIPE_HANDLE:
1109                 if (val) {
1110                         if (pn->pipe_state > PIPE_IDLE) {
1111                                 err = -EFAULT;
1112                                 break;
1113                         }
1114                         pn->pipe_handle = val;
1115                         break;
1116                 }
1117 #endif
1118
1119         case PNPIPE_ENCAP:
1120                 if (val && val != PNPIPE_ENCAP_IP) {
1121                         err = -EINVAL;
1122                         break;
1123                 }
1124                 if (!pn->ifindex == !val)
1125                         break; /* Nothing to do! */
1126                 if (!capable(CAP_NET_ADMIN)) {
1127                         err = -EPERM;
1128                         break;
1129                 }
1130                 if (val) {
1131                         release_sock(sk);
1132                         err = gprs_attach(sk);
1133                         if (err > 0) {
1134                                 pn->ifindex = err;
1135                                 err = 0;
1136                         }
1137                 } else {
1138                         pn->ifindex = 0;
1139                         release_sock(sk);
1140                         gprs_detach(sk);
1141                         err = 0;
1142                 }
1143                 goto out_norel;
1144
1145 #ifdef CONFIG_PHONET_PIPECTRLR
1146         case PNPIPE_ENABLE:
1147                 if (pn->pipe_state <= PIPE_IDLE) {
1148                         err = -ENOTCONN;
1149                         break;
1150                 }
1151                 err = pipe_handler_enable_pipe(sk, val);
1152                 break;
1153 #endif
1154
1155         default:
1156                 err = -ENOPROTOOPT;
1157         }
1158         release_sock(sk);
1159
1160 out_norel:
1161         return err;
1162 }
1163
1164 static int pep_getsockopt(struct sock *sk, int level, int optname,
1165                                 char __user *optval, int __user *optlen)
1166 {
1167         struct pep_sock *pn = pep_sk(sk);
1168         int len, val;
1169
1170         if (level != SOL_PNPIPE)
1171                 return -ENOPROTOOPT;
1172         if (get_user(len, optlen))
1173                 return -EFAULT;
1174
1175         switch (optname) {
1176         case PNPIPE_ENCAP:
1177                 val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE;
1178                 break;
1179
1180         case PNPIPE_IFINDEX:
1181                 val = pn->ifindex;
1182                 break;
1183
1184 #ifdef CONFIG_PHONET_PIPECTRLR
1185         case PNPIPE_ENABLE:
1186                 if (pn->pipe_state <= PIPE_IDLE)
1187                         return -ENOTCONN;
1188                 val = pn->pipe_state != PIPE_DISABLED;
1189                 break;
1190 #endif
1191
1192         default:
1193                 return -ENOPROTOOPT;
1194         }
1195
1196         len = min_t(unsigned int, sizeof(int), len);
1197         if (put_user(len, optlen))
1198                 return -EFAULT;
1199         if (put_user(val, (int __user *) optval))
1200                 return -EFAULT;
1201         return 0;
1202 }
1203
1204 static int pipe_skb_send(struct sock *sk, struct sk_buff *skb)
1205 {
1206         struct pep_sock *pn = pep_sk(sk);
1207         struct pnpipehdr *ph;
1208         int err;
1209
1210         if (pn_flow_safe(pn->tx_fc) &&
1211             !atomic_add_unless(&pn->tx_credits, -1, 0)) {
1212                 kfree_skb(skb);
1213                 return -ENOBUFS;
1214         }
1215
1216         skb_push(skb, 3 + pn->aligned);
1217         skb_reset_transport_header(skb);
1218         ph = pnp_hdr(skb);
1219         ph->utid = 0;
1220         if (pn->aligned) {
1221                 ph->message_id = PNS_PIPE_ALIGNED_DATA;
1222                 ph->data[0] = 0; /* padding */
1223         } else
1224                 ph->message_id = PNS_PIPE_DATA;
1225         ph->pipe_handle = pn->pipe_handle;
1226 #ifdef CONFIG_PHONET_PIPECTRLR
1227         err = pn_skb_send(sk, skb, &pn->remote_pep);
1228 #else
1229         err = pn_skb_send(sk, skb, &pipe_srv);
1230 #endif
1231
1232         if (err && pn_flow_safe(pn->tx_fc))
1233                 atomic_inc(&pn->tx_credits);
1234         return err;
1235
1236 }
1237
1238 static int pep_sendmsg(struct kiocb *iocb, struct sock *sk,
1239                         struct msghdr *msg, size_t len)
1240 {
1241         struct pep_sock *pn = pep_sk(sk);
1242         struct sk_buff *skb;
1243         long timeo;
1244         int flags = msg->msg_flags;
1245         int err, done;
1246
1247         if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|
1248                                 MSG_CMSG_COMPAT)) ||
1249                         !(msg->msg_flags & MSG_EOR))
1250                 return -EOPNOTSUPP;
1251
1252         skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len,
1253                                         flags & MSG_DONTWAIT, &err);
1254         if (!skb)
1255                 return err;
1256
1257         skb_reserve(skb, MAX_PHONET_HEADER + 3);
1258         err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1259         if (err < 0)
1260                 goto outfree;
1261
1262         lock_sock(sk);
1263         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1264         if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) {
1265                 err = -ENOTCONN;
1266                 goto out;
1267         }
1268         if (sk->sk_state != TCP_ESTABLISHED) {
1269                 /* Wait until the pipe gets to enabled state */
1270 disabled:
1271                 err = sk_stream_wait_connect(sk, &timeo);
1272                 if (err)
1273                         goto out;
1274
1275                 if (sk->sk_state == TCP_CLOSE_WAIT) {
1276                         err = -ECONNRESET;
1277                         goto out;
1278                 }
1279         }
1280         BUG_ON(sk->sk_state != TCP_ESTABLISHED);
1281
1282         /* Wait until flow control allows TX */
1283         done = atomic_read(&pn->tx_credits);
1284         while (!done) {
1285                 DEFINE_WAIT(wait);
1286
1287                 if (!timeo) {
1288                         err = -EAGAIN;
1289                         goto out;
1290                 }
1291                 if (signal_pending(current)) {
1292                         err = sock_intr_errno(timeo);
1293                         goto out;
1294                 }
1295
1296                 prepare_to_wait(sk_sleep(sk), &wait,
1297                                 TASK_INTERRUPTIBLE);
1298                 done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits));
1299                 finish_wait(sk_sleep(sk), &wait);
1300
1301                 if (sk->sk_state != TCP_ESTABLISHED)
1302                         goto disabled;
1303         }
1304
1305         err = pipe_skb_send(sk, skb);
1306         if (err >= 0)
1307                 err = len; /* success! */
1308         skb = NULL;
1309 out:
1310         release_sock(sk);
1311 outfree:
1312         kfree_skb(skb);
1313         return err;
1314 }
1315
1316 int pep_writeable(struct sock *sk)
1317 {
1318         struct pep_sock *pn = pep_sk(sk);
1319
1320         return atomic_read(&pn->tx_credits);
1321 }
1322
1323 int pep_write(struct sock *sk, struct sk_buff *skb)
1324 {
1325         struct sk_buff *rskb, *fs;
1326         int flen = 0;
1327
1328         if (pep_sk(sk)->aligned)
1329                 return pipe_skb_send(sk, skb);
1330
1331         rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC);
1332         if (!rskb) {
1333                 kfree_skb(skb);
1334                 return -ENOMEM;
1335         }
1336         skb_shinfo(rskb)->frag_list = skb;
1337         rskb->len += skb->len;
1338         rskb->data_len += rskb->len;
1339         rskb->truesize += rskb->len;
1340
1341         /* Avoid nested fragments */
1342         skb_walk_frags(skb, fs)
1343                 flen += fs->len;
1344         skb->next = skb_shinfo(skb)->frag_list;
1345         skb_frag_list_init(skb);
1346         skb->len -= flen;
1347         skb->data_len -= flen;
1348         skb->truesize -= flen;
1349
1350         skb_reserve(rskb, MAX_PHONET_HEADER + 3);
1351         return pipe_skb_send(sk, rskb);
1352 }
1353
1354 struct sk_buff *pep_read(struct sock *sk)
1355 {
1356         struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue);
1357
1358         if (sk->sk_state == TCP_ESTABLISHED)
1359                 pipe_grant_credits(sk);
1360         return skb;
1361 }
1362
1363 static int pep_recvmsg(struct kiocb *iocb, struct sock *sk,
1364                         struct msghdr *msg, size_t len, int noblock,
1365                         int flags, int *addr_len)
1366 {
1367         struct sk_buff *skb;
1368         int err;
1369
1370         if (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL|
1371                         MSG_NOSIGNAL|MSG_CMSG_COMPAT))
1372                 return -EOPNOTSUPP;
1373
1374         if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE)))
1375                 return -ENOTCONN;
1376
1377         if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) {
1378                 /* Dequeue and acknowledge control request */
1379                 struct pep_sock *pn = pep_sk(sk);
1380
1381                 if (flags & MSG_PEEK)
1382                         return -EOPNOTSUPP;
1383                 skb = skb_dequeue(&pn->ctrlreq_queue);
1384                 if (skb) {
1385                         pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR,
1386                                                 GFP_KERNEL);
1387                         msg->msg_flags |= MSG_OOB;
1388                         goto copy;
1389                 }
1390                 if (flags & MSG_OOB)
1391                         return -EINVAL;
1392         }
1393
1394         skb = skb_recv_datagram(sk, flags, noblock, &err);
1395         lock_sock(sk);
1396         if (skb == NULL) {
1397                 if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT)
1398                         err = -ECONNRESET;
1399                 release_sock(sk);
1400                 return err;
1401         }
1402
1403         if (sk->sk_state == TCP_ESTABLISHED)
1404                 pipe_grant_credits(sk);
1405         release_sock(sk);
1406 copy:
1407         msg->msg_flags |= MSG_EOR;
1408         if (skb->len > len)
1409                 msg->msg_flags |= MSG_TRUNC;
1410         else
1411                 len = skb->len;
1412
1413         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len);
1414         if (!err)
1415                 err = (flags & MSG_TRUNC) ? skb->len : len;
1416
1417         skb_free_datagram(sk, skb);
1418         return err;
1419 }
1420
1421 static void pep_sock_unhash(struct sock *sk)
1422 {
1423         struct pep_sock *pn = pep_sk(sk);
1424         struct sock *skparent = NULL;
1425
1426         lock_sock(sk);
1427
1428 #ifndef CONFIG_PHONET_PIPECTRLR
1429         if ((1 << sk->sk_state) & ~(TCPF_CLOSE|TCPF_LISTEN)) {
1430                 skparent = pn->listener;
1431                 release_sock(sk);
1432
1433                 pn = pep_sk(skparent);
1434                 lock_sock(skparent);
1435                 sk_del_node_init(sk);
1436                 sk = skparent;
1437         }
1438 #endif
1439         /* Unhash a listening sock only when it is closed
1440          * and all of its active connected pipes are closed. */
1441         if (hlist_empty(&pn->hlist))
1442                 pn_sock_unhash(&pn->pn_sk.sk);
1443         release_sock(sk);
1444
1445         if (skparent)
1446                 sock_put(skparent);
1447 }
1448
1449 static struct proto pep_proto = {
1450         .close          = pep_sock_close,
1451         .accept         = pep_sock_accept,
1452 #ifdef CONFIG_PHONET_PIPECTRLR
1453         .connect        = pep_sock_connect,
1454 #endif
1455         .ioctl          = pep_ioctl,
1456         .init           = pep_init,
1457         .setsockopt     = pep_setsockopt,
1458         .getsockopt     = pep_getsockopt,
1459         .sendmsg        = pep_sendmsg,
1460         .recvmsg        = pep_recvmsg,
1461         .backlog_rcv    = pep_do_rcv,
1462         .hash           = pn_sock_hash,
1463         .unhash         = pep_sock_unhash,
1464         .get_port       = pn_sock_get_port,
1465         .obj_size       = sizeof(struct pep_sock),
1466         .owner          = THIS_MODULE,
1467         .name           = "PNPIPE",
1468 };
1469
1470 static struct phonet_protocol pep_pn_proto = {
1471         .ops            = &phonet_stream_ops,
1472         .prot           = &pep_proto,
1473         .sock_type      = SOCK_SEQPACKET,
1474 };
1475
1476 static int __init pep_register(void)
1477 {
1478         return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto);
1479 }
1480
1481 static void __exit pep_unregister(void)
1482 {
1483         phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto);
1484 }
1485
1486 module_init(pep_register);
1487 module_exit(pep_unregister);
1488 MODULE_AUTHOR("Remi Denis-Courmont, Nokia");
1489 MODULE_DESCRIPTION("Phonet pipe protocol");
1490 MODULE_LICENSE("GPL");
1491 MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE);