src/common/session.c

   1 /*
   2  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
   3  * Copyright (C) 1999-2003 Hiroyuki Yamamoto
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #  include "config.h"
  22 #endif
  23
  24 #include "defs.h"
  25
  26 #include <glib.h>
  27
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31 #include <sys/types.h>
  32 #include <unistd.h>
  33 #include <sys/signal.h>
  34 #include <sys/wait.h>
  35 #include <sys/time.h>
  36
  37 #include "session.h"
  38 #include "utils.h"
  39
  40 static gint session_close               (Session        *session);
  41
  42 static gchar *session_recv_msg          (Session        *session);
  43
  44 static guchar *session_read_data        (Session        *session,
  45                                          guint           size);
  46
  47 static gint session_send_data_to_sock           (Session        *session,
  48                                                  const guchar   *data,
  49                                                  guint           size);
  50 static guchar *session_recv_data_from_sock      (Session        *session,
  51                                                  guint           size);
  52
  53 static guchar *session_recv_data_from_sock_unescape     (Session *session,
  54                                                          guint    size,
  55                                                          guint   *actual_size);
  56
  57 gboolean session_parent_input_cb        (GIOChannel     *source,
  58                                          GIOCondition    condition,
  59                                          gpointer        data);
  60
  61 gboolean session_child_input            (Session        *session);
  62
  63
  64 /*!
  65  *\brief        init session members to zero
  66  *
  67  *\param        session to be initialized
  68  */
  69 void session_init(Session *session)
  70 {
  71         session->type = 0;
  72         session->sock = NULL;
  73
  74         session->server = NULL;
  75         session->port = 0;
  76         session->state = SESSION_READY;
  77         session->last_access_time = time(NULL);
  78         session->data = NULL;
  79
  80         session->read_ch = NULL;
  81         session->write_ch = NULL;
  82 }
  83
  84 /*!
  85  *\brief        Set up parent and child process
  86  *              Childloop: Read commands from parent,
  87  *              send to server, get answer, pass to parent
  88  *
  89  *\param        session Contains session information
  90  *              server to connect to
  91  *              port to connect to
  92  *
  93  *\return        0 : success
  94  *              -1 : pipe / fork errors (parent)
  95  *               1 : connection error (child)
  96  */
  97 gint session_connect(Session *session, const gchar *server, gushort port)
  98 {
  99         pid_t pid;
 100         gint pipe_fds1[2], pipe_fds2[2];
 101         SockInfo *sock;
 102         gchar *str;
 103
 104         session->server = g_strdup(server);
 105         session->port = port;
 106
 107         if (pipe(pipe_fds1) < 0) {
 108                 perror("pipe");
 109                 return -1;
 110         }
 111         if (pipe(pipe_fds2) < 0) {
 112                 perror("pipe");
 113                 close(pipe_fds1[0]);
 114                 close(pipe_fds1[1]);
 115                 return -1;
 116         }
 117
 118         if ((pid = fork()) < 0) {
 119                 perror("fork");
 120                 return -1;
 121         }
 122
 123         if (pid != 0) {
 124                 session->child_pid = pid;
 125                 session->read_ch = g_io_channel_unix_new(pipe_fds2[0]);
 126                 session->write_ch = g_io_channel_unix_new(pipe_fds1[1]);
 127                 close(pipe_fds1[0]);
 128                 close(pipe_fds2[1]);
 129                 session->read_tag = g_io_add_watch(session->read_ch, G_IO_IN,
 130                                                    session_parent_input_cb,
 131                                                    session);
 132                 return 0;
 133         }
 134
 135         /* child process */
 136
 137         session->read_ch = g_io_channel_unix_new(pipe_fds1[0]);
 138         session->write_ch = g_io_channel_unix_new(pipe_fds2[1]);
 139         close(pipe_fds1[1]);
 140         close(pipe_fds2[0]);
 141
 142         debug_print("session: child: connecting to %s:%d ...\n", server, port);
 143
 144         if ((sock = sock_connect(server, port)) == NULL) {
 145                 session_send_msg(session, SESSION_MSG_ERROR,
 146                                  "can't connect to server.");
 147                 session_close(session);
 148                 _exit(1);
 149         }
 150
 151 #if USE_OPENSSL
 152         if (session->ssl_type == SSL_TUNNEL && !ssl_init_socket(sock)) {
 153                 session_send_msg(session, SESSION_MSG_ERROR,
 154                                  "can't initialize SSL.");
 155                 session_close(session);
 156                 _exit(1);
 157         }
 158 #endif
 159
 160         debug_print("session: child: connected\n");
 161
 162         session->sock = sock;
 163         session->state = SESSION_RECV;
 164
 165         if ((str = sock_getline(sock)) == NULL) {
 166                 session_send_msg(session, SESSION_MSG_ERROR,
 167                                  "can't get server response.");
 168                 session_close(session);
 169                 _exit(1);
 170         }
 171         strretchomp(str);
 172         session_send_msg(session, SESSION_MSG_NORMAL, str);
 173         g_free(str);
 174
 175         while (session_child_input(session) == TRUE)
 176                 ;
 177
 178         session_close(session);
 179
 180         debug_print("session: child: disconnected\n");
 181
 182         _exit(0);
 183 }
 184
 185 /*!
 186  *\brief        child and parent: send DISCONNECT message to other process
 187  *
 188  *\param        session Contains session information
 189  *
 190  *\return        0 : success
 191  */
 192 gint session_disconnect(Session *session)
 193 {
 194         debug_print("session: %s: session_disconnect()\n",
 195                     session->child_pid == 0 ? "child" : "parent");
 196         session_send_msg(session, SESSION_MSG_CONTROL, "DISCONNECT");
 197         return 0;
 198 }
 199
 200 /*!
 201  *\brief        parent ?
 202  *
 203  *\param        session Contains session information
 204  */
 205 void session_destroy(Session *session)
 206 {
 207         g_return_if_fail(session != NULL);
 208         g_return_if_fail(session->destroy != NULL);
 209
 210         debug_print("session: session_destroy()\n");
 211         session_close(session);
 212         session->destroy(session);
 213         g_free(session->server);
 214         g_free(session);
 215 }
 216
 217 void session_set_recv_message_notify(Session *session,
 218                                      RecvMsgNotify notify_func, gpointer data)
 219 {
 220         session->recv_msg_notify = notify_func;
 221         session->recv_msg_notify_data = data;
 222 }
 223
 224 void session_set_recv_data_progressive_notify
 225                                         (Session *session,
 226                                          RecvDataProgressiveNotify notify_func,
 227                                          gpointer data)
 228 {
 229         session->recv_data_progressive_notify = notify_func,
 230         session->recv_data_progressive_notify_data = data;
 231 }
 232
 233 void session_set_recv_data_notify(Session *session, RecvDataNotify notify_func,
 234                                   gpointer data)
 235 {
 236         session->recv_data_notify = notify_func;
 237         session->recv_data_notify_data = data;
 238 }
 239
 240 void session_set_send_data_progressive_notify
 241                                         (Session *session,
 242                                          SendDataProgressiveNotify notify_func,
 243                                          gpointer data)
 244 {
 245         session->send_data_progressive_notify = notify_func;
 246         session->send_data_progressive_notify_data = data;
 247 }
 248
 249 void session_set_send_data_notify(Session *session, SendDataNotify notify_func,
 250                                   gpointer data)
 251 {
 252         session->send_data_notify = notify_func;
 253         session->send_data_notify_data = data;
 254 }
 255
 256 /*!
 257  *\brief        child and parent cleanup (child closes first)
 258  *
 259  *\param        session Contains session information
 260  *
 261  *\return        0 : success
 262  */
 263 static gint session_close(Session *session)
 264 {
 265         g_return_val_if_fail(session != NULL, -1);
 266
 267         debug_print("session: %s: session_close()\n",
 268                     session->child_pid == 0 ? "child" : "parent");
 269
 270         if (session->read_tag > 0) {
 271                 g_source_remove(session->read_tag);
 272                 session->read_tag = 0;
 273         }
 274
 275         if (session->read_ch) {
 276                 g_io_channel_close(session->read_ch);
 277                 g_io_channel_unref(session->read_ch);
 278                 session->read_ch = NULL;
 279         }
 280
 281         if (session->write_ch) {
 282                 g_io_channel_close(session->write_ch);
 283                 g_io_channel_unref(session->write_ch);
 284                 session->write_ch = NULL;
 285         }
 286
 287         if (session->sock) {
 288                 sock_close(session->sock);
 289                 session->sock = NULL;
 290                 session->state = SESSION_DISCONNECTED;
 291         }
 292
 293         if (session->child_pid) {
 294                 if (session->state != SESSION_DISCONNECTED)
 295                         kill(session->child_pid, SIGTERM);
 296                 waitpid(session->child_pid, NULL, 0);
 297                 session->child_pid = 0;
 298         }
 299
 300         return 0;
 301 }
 302
 303 /*!
 304  *\brief        child and parent: send control message to other process
 305  *
 306  *\param        session Contains session information
 307  *              type Kind of data (commands or message data)
 308  *              msg Data
 309  *
 310  *\return        0 : success
 311  *              -1 : error
 312  */
 313 gint session_send_msg(Session *session, SessionMsgType type, const gchar *msg)
 314 {
 315         gchar *prefix;
 316         gchar *str;
 317         gchar *cur;
 318         guint size;
 319         guint bytes_written;
 320
 321         switch (type) {
 322         case SESSION_MSG_NORMAL:
 323                 prefix = "MESSAGE"; break;
 324         case SESSION_MSG_SEND_DATA:
 325                 prefix = "SENDDATA"; break;
 326         case SESSION_MSG_RECV_DATA:
 327                 prefix = "RECVDATA"; break;
 328         case SESSION_MSG_CONTROL:
 329                 prefix = "CONTROL"; break;
 330         case SESSION_MSG_ERROR:
 331                 prefix = "ERROR"; break;
 332         default:
 333                 return -1;
 334         }
 335
 336         cur = str = g_strdup_printf("%s %s\n", prefix, msg);
 337         size = strlen(str);
 338
 339         while (size > 0) {
 340                 if (g_io_channel_write(session->write_ch, cur, size,
 341                                        &bytes_written)
 342                     != G_IO_ERROR_NONE || bytes_written == 0) {
 343                         g_warning("%s: sending message failed.\n",
 344                                   session->child_pid == 0 ? "child" : "parent");
 345                         g_free(str);
 346                         return -1;
 347                 }
 348                 size -= bytes_written;
 349                 cur += bytes_written;
 350         }
 351
 352         g_free(str);
 353
 354         return 0;
 355 }
 356
 357 /*!
 358  *\brief        child and parent receive function
 359  *
 360  *\param        session Contains session information
 361  *
 362  *\return       Message read by current session
 363  */
 364 static gchar *session_recv_msg(Session *session)
 365 {
 366         gchar buf[BUFFSIZE];
 367         gchar *str = NULL;
 368         guint size = 1;
 369         guint bytes_read;
 370
 371         for (;;) {
 372                 if (g_io_channel_read(session->read_ch, buf, sizeof(buf) - 1,
 373                                       &bytes_read)
 374                     != G_IO_ERROR_NONE || bytes_read == 0) {
 375                         g_warning("%s: receiving message failed.\n",
 376                                   session->child_pid == 0 ? "child" : "parent");
 377                         g_free(str);
 378                         str = NULL;
 379                         break;
 380                 }
 381
 382                 size += bytes_read;
 383                 buf[bytes_read] = '\0';
 384
 385                 if (!str)
 386                         str = g_strdup(buf);
 387                 else {
 388                         str = g_realloc(str, size);
 389                         strcat(str, buf);
 390                 }
 391                 if (str[size - 2] == '\n') {
 392                         str[size - 2] = '\0';
 393                         break;
 394                 }
 395         }
 396
 397         return str;
 398 }
 399
 400 #if USE_OPENSSL
 401 gint session_start_tls(Session *session)
 402 {
 403         gchar *ctl_msg;
 404
 405         session_send_msg(session, SESSION_MSG_CONTROL, "STARTTLS");
 406         ctl_msg = session_recv_msg(session);
 407         if (!ctl_msg || strcmp(ctl_msg, "CONTROL STARTTLSOK") != 0) {
 408                 g_free(ctl_msg);
 409                 return -1;
 410         }
 411         g_free(ctl_msg);
 412
 413         return 0;
 414 }
 415 #endif
 416
 417 /*!
 418  *\brief        parent (child?): send data to other process
 419  *
 420  *\param        session Contains session information
 421  *              data Data to send
 422  *              size Bytes to send
 423  *
 424  *\return        0 : success
 425  *              -1 : error
 426  */
 427 gint session_send_data(Session *session, const guchar *data, guint size)
 428 {
 429         gchar *msg;
 430         const guchar *cur = data;
 431         guint bytes_written;
 432         GIOError err;
 433
 434         session_send_msg(session, SESSION_MSG_SEND_DATA, itos(size));
 435         if ((msg = session_recv_msg(session)) == NULL)
 436                 return -1;
 437         g_free(msg);
 438
 439         while (size > 0) {
 440                 if ((err = g_io_channel_write(session->write_ch, (guchar *)cur,
 441                                               size, &bytes_written))
 442                     != G_IO_ERROR_NONE || bytes_written == 0) {
 443                         g_warning("%s: sending data failed: %d\n",
 444                                   session->child_pid == 0 ? "child" : "parent",
 445                                   err);
 446                         return -1;
 447                 }
 448                 size -= bytes_written;
 449                 cur += bytes_written;
 450                 debug_print("session: %s: sent %d bytes of data\n",
 451                             session->child_pid == 0 ? "child" : "parent",
 452                             bytes_written);
 453         }
 454
 455         return 0;
 456 }
 457
 458 gint session_recv_data(Session *session, guint size, gboolean unescape_dot)
 459 {
 460         if (unescape_dot) {
 461                 gchar buf[BUFFSIZE];
 462
 463                 g_snprintf(buf, sizeof(buf), "%d UNESCAPE", size);
 464                 session_send_msg(session, SESSION_MSG_RECV_DATA, buf);
 465         } else
 466                 session_send_msg(session, SESSION_MSG_RECV_DATA, itos(size));
 467         return 0;
 468 }
 469
 470 /*!
 471  *\brief        child (parent?): read data from other process
 472  *
 473  *\param        session Contains session information
 474  *              size Bytes to read
 475  *
 476  *\return       data read from session
 477  */
 478 static guchar *session_read_data(Session *session, guint size)
 479 {
 480         guchar *data;
 481         guchar *cur;
 482         guint bytes_read;
 483         GIOError err;
 484
 485         cur = data = g_malloc(size);
 486
 487         while (size > 0) {
 488                 if ((err = g_io_channel_read(session->read_ch, cur, size,
 489                                              &bytes_read))
 490                     != G_IO_ERROR_NONE || bytes_read == 0) {
 491                         g_warning("%s: reading data failed: %d\n",
 492                                   session->child_pid == 0 ? "child" : "parent",
 493                                   err);
 494                         g_free(data);
 495                         return NULL;
 496                 }
 497                 size -= bytes_read;
 498                 cur += bytes_read;
 499                 debug_print("session: %s: received %d bytes of data\n",
 500                             session->child_pid == 0 ? "child" : "parent",
 501                             bytes_read);
 502         }
 503
 504         return data;
 505 }
 506
 507 #define MAX_CHUNK_SIZE 4096
 508
 509 /*!
 510  *\brief        child: Send session data to server
 511  *
 512  *\param        session Contains session information
 513  *              data Data to send to server
 514  *              size Bytes to send
 515  *
 516  *\return        0 : success
 517  *              -1 : error
 518  */
 519 static gint session_send_data_to_sock(Session *session, const guchar *data,
 520                                       guint size)
 521 {
 522         const guchar *cur = data;
 523         gint bytes_written;
 524         gint total_write_len = 0;
 525         guint left = size;
 526         gchar buf[BUFFSIZE];
 527         gchar *msg;
 528         struct timeval tv_prev, tv_cur;
 529
 530         gettimeofday(&tv_prev, NULL);
 531
 532         while (1) {
 533                 bytes_written = sock_write(session->sock, cur,
 534                                            MIN(left, MAX_CHUNK_SIZE));
 535                 if (bytes_written <= 0)
 536                         return -1;
 537                 left -= bytes_written;
 538                 cur += bytes_written;
 539                 total_write_len += bytes_written;
 540                 if (left == 0)
 541                         break;
 542
 543                 gettimeofday(&tv_cur, NULL);
 544                 if (tv_cur.tv_sec - tv_prev.tv_sec > 0 ||
 545                     tv_cur.tv_usec - tv_prev.tv_usec > UI_REFRESH_INTERVAL) {
 546                         g_snprintf(buf, sizeof(buf), "DATASENDINPROG %d %d",
 547                                    total_write_len, size);
 548                         session_send_msg(session, SESSION_MSG_CONTROL, buf);
 549                         if ((msg = session_recv_msg(session)) == NULL)
 550                                 return -1;
 551                         g_free(msg);
 552                         gettimeofday(&tv_prev, NULL);
 553                 }
 554         }
 555
 556         return 0;
 557 }
 558
 559 /*!
 560  *\brief        child: Read answer/data from server
 561  *
 562  *\param        session Contains session information
 563  *              size Max bytes to receive
 564  *
 565  *\return       Server answer
 566  */
 567 static guchar *session_recv_data_from_sock(Session *session, guint size)
 568 {
 569         guchar *data;
 570         guchar *cur;
 571         gint bytes_read;
 572         gint total_read_len = 0;
 573         guint left = size;
 574         gchar buf[BUFFSIZE];
 575         gchar *msg;
 576         struct timeval tv_prev, tv_cur;
 577
 578         gettimeofday(&tv_prev, NULL);
 579
 580         cur = data = g_malloc(size);
 581
 582         while (1) {
 583                 bytes_read = sock_read(session->sock, cur, left);
 584                 if (bytes_read <= 0) {
 585                         g_free(data);
 586                         return NULL;
 587                 }
 588                 debug_print("session: child: "
 589                             "received %d bytes of data from sock\n",
 590                             bytes_read);
 591                 left -= bytes_read;
 592                 cur += bytes_read;
 593                 total_read_len += bytes_read;
 594                 if (left == 0)
 595                         break;
 596
 597                 gettimeofday(&tv_cur, NULL);
 598                 if (tv_cur.tv_sec - tv_prev.tv_sec > 0 ||
 599                     tv_cur.tv_usec - tv_prev.tv_usec > UI_REFRESH_INTERVAL) {
 600                         g_snprintf(buf, sizeof(buf), "DATARECVINPROG %d %d",
 601                                    total_read_len, size);
 602                         session_send_msg(session, SESSION_MSG_CONTROL, buf);
 603                         if ((msg = session_recv_msg(session)) == NULL) {
 604                                 g_free(data);
 605                                 return NULL;
 606                         }
 607                         g_free(msg);
 608                         gettimeofday(&tv_prev, NULL);
 609                 }
 610         }
 611
 612         return data;
 613 }
 614
 615 static guchar *session_recv_data_from_sock_unescape(Session *session,
 616                                                     guint size,
 617                                                     guint *actual_size)
 618 {
 619         GString *data;
 620         guchar *ret_data;
 621         gint bytes_read;
 622         gchar buf[BUFFSIZE];
 623         gchar *msg;
 624         struct timeval tv_prev, tv_cur;
 625
 626         gettimeofday(&tv_prev, NULL);
 627
 628         data = g_string_sized_new(size + 1);
 629         *actual_size = 0;
 630
 631         while (1) {
 632                 bytes_read = sock_gets(session->sock, buf, sizeof(buf));
 633                 if (bytes_read <= 0) {
 634                         g_string_free(data, TRUE);
 635                         return NULL;
 636                 }
 637
 638                 if (buf[0] == '.' && buf[1] == '\r' && buf[2] == '\n')
 639                         break;
 640                 if (buf[0] == '.' && buf[1] == '.')
 641                         g_string_append(data, buf + 1);
 642                 else
 643                         g_string_append(data, buf);
 644
 645                 gettimeofday(&tv_cur, NULL);
 646                 if (tv_cur.tv_sec - tv_prev.tv_sec > 0 ||
 647                     tv_cur.tv_usec - tv_prev.tv_usec > UI_REFRESH_INTERVAL) {
 648                         g_snprintf(buf, sizeof(buf), "DATARECVINPROG %d %d",
 649                                    data->len, MAX(data->len, size));
 650                         session_send_msg(session, SESSION_MSG_CONTROL, buf);
 651                         if ((msg = session_recv_msg(session)) == NULL) {
 652                                 g_string_free(data, TRUE);
 653                                 return NULL;
 654                         }
 655                         g_free(msg);
 656                         gettimeofday(&tv_prev, NULL);
 657                 }
 658         }
 659
 660         ret_data = data->str;
 661         *actual_size = data->len;
 662         g_string_free(data, FALSE);
 663
 664         return ret_data;
 665 }
 666
 667 /*!
 668  *\brief        Return if message is an internal command or server data
 669  *
 670  *\param        str Message to analyze
 671  *
 672  *\return       Type of message
 673  */
 674 static SessionMsgType session_get_msg_type(const gchar *str)
 675 {
 676         if (!strncmp(str, "MESSAGE ", 8))
 677                 return SESSION_MSG_NORMAL;
 678         else if (!strncmp(str, "SENDDATA ", 9))
 679                 return SESSION_MSG_SEND_DATA;
 680         else if (!strncmp(str, "RECVDATA ", 9))
 681                 return SESSION_MSG_RECV_DATA;
 682         else if (!strncmp(str, "CONTROL ", 8))
 683                 return SESSION_MSG_CONTROL;
 684         else if (!strncmp(str, "ERROR ", 6))
 685                 return SESSION_MSG_ERROR;
 686         else
 687                 return SESSION_MSG_UNKNOWN;
 688 }
 689
 690 /*!
 691  *\brief        parent: Received data from child
 692  *
 693  *\param        source Channel watching child pipe
 694  *              condition Unused (IN, HUP, OUT)
 695  *              data Contains session information
 696  *
 697  *\return       FALSE to remove watching channel
 698  */
 699 gboolean session_parent_input_cb(GIOChannel *source, GIOCondition condition,
 700                                  gpointer data)
 701 {
 702         Session *session = SESSION(data);
 703         gchar *msg;
 704         gchar *msg_data;
 705         gint len;
 706         gint total;
 707         guchar *recv_data;
 708         guint size;
 709         gint ret;
 710
 711         if ((msg = session_recv_msg(session)) == NULL) {
 712                 session->state = SESSION_ERROR;
 713                 return FALSE;
 714         }
 715
 716         switch (session_get_msg_type(msg)) {
 717         case SESSION_MSG_NORMAL:
 718                 msg_data = msg + strlen("MESSAGE ");
 719                 ret = session->recv_msg(session, msg_data);
 720                 session->recv_msg_notify(session, msg_data,
 721                                          session->recv_msg_notify_data);
 722                 if (ret > 0)
 723                         session_send_msg(session, SESSION_MSG_CONTROL,
 724                                          "CONTINUE");
 725                 else if (ret < 0) {
 726                         session->state = SESSION_ERROR;
 727                         g_free(msg);
 728                         return FALSE;
 729                 }
 730                 break;
 731         case SESSION_MSG_SEND_DATA:
 732                 msg_data = msg + strlen("SENDDATA ");
 733                 size = atoi(msg_data);
 734                 session_send_msg(session, SESSION_MSG_CONTROL, "ACCEPTDATA");
 735                 recv_data = session_read_data(session, size);
 736                 if (!recv_data) {
 737                         session->state = SESSION_ERROR;
 738                         g_free(msg);
 739                         return FALSE;
 740                 }
 741                 ret = session->recv_data_finished(session, recv_data, size);
 742                 g_free(recv_data);
 743                 session->recv_data_notify(session, size,
 744                                           session->recv_data_notify_data);
 745                 if (ret > 0)
 746                         session_send_msg(session, SESSION_MSG_CONTROL,
 747                                          "CONTINUE");
 748                 else if (ret < 0) {
 749                         session->state = SESSION_ERROR;
 750                         g_free(msg);
 751                         return FALSE;
 752                 }
 753                 break;
 754         case SESSION_MSG_RECV_DATA:
 755                 break;
 756         case SESSION_MSG_CONTROL:
 757                 msg_data = msg + strlen("CONTROL ");
 758                 if (!strncmp(msg_data, "DATARECVINPROG ", 15)) {
 759                         ret = sscanf(msg_data,
 760                                      "DATARECVINPROG %d %d", &len, &total);
 761                         if (ret != 2) {
 762                                 g_warning("wrong control message: %s\n", msg);
 763                                 session->state = SESSION_ERROR;
 764                                 g_free(msg);
 765                                 return FALSE;
 766                         }
 767                         session_send_msg(session, SESSION_MSG_CONTROL,
 768                                          "CONTINUE");
 769                         session->recv_data_progressive_notify
 770                                 (session, len, total,
 771                                  session->recv_data_progressive_notify_data);
 772                 } else if (!strncmp(msg_data, "DATASENDINPROG ", 15)) {
 773                         ret = sscanf(msg_data,
 774                                      "DATASENDINPROG %d %d", &len, &total);
 775                         if (ret != 2) {
 776                                 g_warning("wrong control message: %s\n", msg);
 777                                 session->state = SESSION_ERROR;
 778                                 g_free(msg);
 779                                 return FALSE;
 780                         }
 781                         session_send_msg(session, SESSION_MSG_CONTROL,
 782                                          "CONTINUE");
 783                         session->send_data_progressive_notify
 784                                 (session, len, total,
 785                                  session->send_data_progressive_notify_data);
 786                 } else if (!strncmp(msg_data, "DATASENT ", 9)) {
 787                         len = atoi(msg_data + 9);
 788                         ret = session->send_data_finished(session, len);
 789                         session->send_data_notify
 790                                 (session, len, session->send_data_notify_data);
 791                 } else if (!strcmp(msg_data, "DISCONNECTED")) {
 792                         session->state = SESSION_DISCONNECTED;
 793                         g_free(msg);
 794                         return FALSE;
 795                 } else {
 796                         g_warning("wrong control message: %s\n", msg);
 797                         session->state = SESSION_ERROR;
 798                         g_free(msg);
 799                         return FALSE;
 800                 }
 801                 break;
 802         case SESSION_MSG_ERROR:
 803         default:
 804                 g_warning("error from child: %s\n", msg + strlen("ERROR "));
 805                 session->state = SESSION_ERROR;
 806                 g_free(msg);
 807                 return FALSE;
 808         }
 809
 810         g_free(msg);
 811         return TRUE;
 812 }
 813
 814 /*!
 815  *\brief        child: Receive control message from parent,
 816  *              transfer data from/to server
 817  *
 818  *\param        session Contains session information
 819  *
 820  *\return       TRUE if more data is available
 821  */
 822 gboolean session_child_input(Session *session)
 823 {
 824         gchar buf[BUFFSIZE];
 825         gchar *msg;
 826         gchar *msg_data;
 827         gchar *str;
 828         guchar *send_data;
 829         guchar *recv_data;
 830         guint size;
 831         guint actual_size;
 832
 833         if ((msg = session_recv_msg(session)) == NULL) {
 834                 session_send_msg(session, SESSION_MSG_ERROR,
 835                                  "receiving message failed.");
 836                 session->state = SESSION_ERROR;
 837                 return FALSE;
 838         }
 839
 840         switch (session_get_msg_type(msg)) {
 841         case SESSION_MSG_NORMAL:
 842                 msg_data = msg + strlen("MESSAGE ");
 843                 session->state = SESSION_SEND;
 844                 sock_puts(session->sock, msg_data);
 845                 session->state = SESSION_RECV;
 846                 str = sock_getline(session->sock);
 847                 if (!str) {
 848                         session_send_msg(session, SESSION_MSG_ERROR,
 849                                          "receiving message failed.");
 850                         session->state = SESSION_ERROR;
 851                         g_free(msg);
 852                         return FALSE;
 853                 }
 854                 strretchomp(str);
 855                 session_send_msg(session, SESSION_MSG_NORMAL, str);
 856                 g_free(str);
 857                 break;
 858         case SESSION_MSG_SEND_DATA:
 859                 msg_data = msg + strlen("SENDDATA ");
 860                 size = atoi(msg_data);
 861                 session_send_msg(session, SESSION_MSG_CONTROL, "ACCEPTDATA");
 862                 send_data = session_read_data(session, size);
 863                 if (!send_data) {
 864                         session_send_msg(session, SESSION_MSG_ERROR,
 865                                          "sending data failed.");
 866                         session->state = SESSION_ERROR;
 867                         g_free(msg);
 868                         return FALSE;
 869                 }
 870                 session->state = SESSION_SEND;
 871                 if (session_send_data_to_sock(session, send_data, size) < 0) {
 872                         session_send_msg(session, SESSION_MSG_ERROR,
 873                                          "sending data failed.");
 874                         session->state = SESSION_ERROR;
 875                         g_free(send_data);
 876                         g_free(msg);
 877                         return FALSE;
 878                 }
 879                 g_free(send_data);
 880                 g_snprintf(buf, sizeof(buf), "DATASENT %d", size);
 881                 session_send_msg(session, SESSION_MSG_CONTROL, buf);
 882                 break;
 883         case SESSION_MSG_RECV_DATA:
 884                 msg_data = msg + strlen("RECVDATA ");
 885                 size = atoi(msg_data);
 886                 session->state = SESSION_RECV;
 887                 if (strstr(msg_data, "UNESCAPE") != NULL) {
 888                         recv_data = session_recv_data_from_sock_unescape
 889                                 (session, size, &actual_size);
 890                         size = actual_size;
 891                 } else
 892                         recv_data = session_recv_data_from_sock(session, size);
 893                 if (!recv_data) {
 894                         session_send_msg(session, SESSION_MSG_ERROR,
 895                                          "receiving data failed.");
 896                         session->state = SESSION_ERROR;
 897                         g_free(msg);
 898                         return FALSE;
 899                 }
 900                 if (session_send_data(session, recv_data, size) < 0) {
 901                         session->state = SESSION_ERROR;
 902                         g_free(recv_data);
 903                         g_free(msg);
 904                         return FALSE;
 905                 }
 906                 g_free(recv_data);
 907                 break;
 908         case SESSION_MSG_CONTROL:
 909                 msg_data = msg + strlen("CONTROL ");
 910                 if (!strcmp(msg_data, "CONTINUE")) {
 911                         session->state = SESSION_RECV;
 912                         str = sock_getline(session->sock);
 913                         if (!str) {
 914                                 session_send_msg(session, SESSION_MSG_ERROR,
 915                                                  "receiving message failed.");
 916                                 session->state = SESSION_ERROR;
 917                                 g_free(msg);
 918                                 return FALSE;
 919                         }
 920                         strretchomp(str);
 921                         session_send_msg(session, SESSION_MSG_NORMAL, str);
 922                         g_free(str);
 923                         break;
 924 #if USE_OPENSSL
 925                 } else if (!strcmp(msg_data, "STARTTLS")) {
 926                         if (!ssl_init_socket_with_method(session->sock,
 927                                                          SSL_METHOD_TLSv1)) {
 928                                 session_send_msg(session, SESSION_MSG_ERROR,
 929                                                  "can't start TLS session.");
 930                                 session->state = SESSION_ERROR;
 931                                 g_free(msg);
 932                                 return FALSE;
 933                         }
 934                         session_send_msg(session, SESSION_MSG_CONTROL,
 935                                          "STARTTLSOK");
 936                         break;
 937 #endif
 938                 } else if (!strcmp(msg_data, "DISCONNECT")) {
 939                         sock_close(session->sock);
 940                         session->sock = NULL;
 941                         session->state = SESSION_DISCONNECTED;
 942                         session_send_msg(session, SESSION_MSG_CONTROL,
 943                                          "DISCONNECTED");
 944                         g_free(msg);
 945                         return FALSE;
 946                 } else {
 947                         session_send_msg(session, SESSION_MSG_ERROR,
 948                                          "wrong control message.");
 949                         session->state = SESSION_ERROR;
 950                         g_free(msg);
 951                         return FALSE;
 952                 }
 953                 break;
 954         case SESSION_MSG_ERROR:
 955         default:
 956                 session_send_msg(session, SESSION_MSG_ERROR,
 957                                  "error received from parent.");
 958                 session->state = SESSION_ERROR;
 959                 g_free(msg);
 960                 return FALSE;
 961         }
 962
 963         g_free(msg);
 964         return TRUE;
 965 }