clientloop.c

   1 /*
   2  * Author: Tatu Ylonen <ylo@cs.hut.fi>
   3  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
   4  *                    All rights reserved
   5  * The main loop for the interactive session (client side).
   6  *
   7  * As far as I am concerned, the code I have written for this software
   8  * can be used freely for any purpose.  Any derived versions of this
   9  * software must be clearly marked as such, and if the derived work is
  10  * incompatible with the protocol description in the RFC file, it must be
  11  * called by a name other than "ssh" or "Secure Shell".
  12  *
  13  *
  14  * Copyright (c) 1999 Theo de Raadt.  All rights reserved.
  15  *
  16  * Redistribution and use in source and binary forms, with or without
  17  * modification, are permitted provided that the following conditions
  18  * are met:
  19  * 1. Redistributions of source code must retain the above copyright
  20  *    notice, this list of conditions and the following disclaimer.
  21  * 2. Redistributions in binary form must reproduce the above copyright
  22  *    notice, this list of conditions and the following disclaimer in the
  23  *    documentation and/or other materials provided with the distribution.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  26  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  27  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  28  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  29  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  30  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  31  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  34  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  *
  36  *
  37  * SSH2 support added by Markus Friedl.
  38  * Copyright (c) 1999, 2000, 2001 Markus Friedl.  All rights reserved.
  39  *
  40  * Redistribution and use in source and binary forms, with or without
  41  * modification, are permitted provided that the following conditions
  42  * are met:
  43  * 1. Redistributions of source code must retain the above copyright
  44  *    notice, this list of conditions and the following disclaimer.
  45  * 2. Redistributions in binary form must reproduce the above copyright
  46  *    notice, this list of conditions and the following disclaimer in the
  47  *    documentation and/or other materials provided with the distribution.
  48  *
  49  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  50  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  51  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  52  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  53  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  54  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  55  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  56  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  57  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  58  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  59  */
  60
  61 #include "includes.h"
  62 RCSID("$OpenBSD: clientloop.c,v 1.115 2003/09/23 20:41:11 markus Exp $");
  63
  64 #include "ssh.h"
  65 #include "ssh1.h"
  66 #include "ssh2.h"
  67 #include "xmalloc.h"
  68 #include "packet.h"
  69 #include "buffer.h"
  70 #include "compat.h"
  71 #include "channels.h"
  72 #include "dispatch.h"
  73 #include "buffer.h"
  74 #include "bufaux.h"
  75 #include "key.h"
  76 #include "kex.h"
  77 #include "log.h"
  78 #include "readconf.h"
  79 #include "clientloop.h"
  80 #include "authfd.h"
  81 #include "atomicio.h"
  82 #include "sshtty.h"
  83 #include "misc.h"
  84 #include "readpass.h"
  85
  86 /* import options */
  87 extern Options options;
  88
  89 /* Flag indicating that stdin should be redirected from /dev/null. */
  90 extern int stdin_null_flag;
  91
  92 /*
  93  * Name of the host we are connecting to.  This is the name given on the
  94  * command line, or the HostName specified for the user-supplied name in a
  95  * configuration file.
  96  */
  97 extern char *host;
  98
  99 /*
 100  * Flag to indicate that we have received a window change signal which has
 101  * not yet been processed.  This will cause a message indicating the new
 102  * window size to be sent to the server a little later.  This is volatile
 103  * because this is updated in a signal handler.
 104  */
 105 static volatile sig_atomic_t received_window_change_signal = 0;
 106 static volatile sig_atomic_t received_signal = 0;
 107
 108 /* Flag indicating whether the user\'s terminal is in non-blocking mode. */
 109 static int in_non_blocking_mode = 0;
 110
 111 /* Common data for the client loop code. */
 112 static int quit_pending;        /* Set to non-zero to quit the client loop. */
 113 static int escape_char;         /* Escape character. */
 114 static int escape_pending;      /* Last character was the escape character */
 115 static int last_was_cr;         /* Last character was a newline. */
 116 static int exit_status;         /* Used to store the exit status of the command. */
 117 static int stdin_eof;           /* EOF has been encountered on standard error. */
 118 static Buffer stdin_buffer;     /* Buffer for stdin data. */
 119 static Buffer stdout_buffer;    /* Buffer for stdout data. */
 120 static Buffer stderr_buffer;    /* Buffer for stderr data. */
 121 static u_long stdin_bytes, stdout_bytes, stderr_bytes;
 122 static u_int buffer_high;/* Soft max buffer size. */
 123 static int connection_in;       /* Connection to server (input). */
 124 static int connection_out;      /* Connection to server (output). */
 125 static int need_rekeying;       /* Set to non-zero if rekeying is requested. */
 126 static int session_closed = 0;  /* In SSH2: login session closed. */
 127
 128 static void client_init_dispatch(void);
 129 int     session_ident = -1;
 130
 131 /*XXX*/
 132 extern Kex *xxx_kex;
 133
 134 /* Restores stdin to blocking mode. */
 135
 136 static void
 137 leave_non_blocking(void)
 138 {
 139         if (in_non_blocking_mode) {
 140                 (void) fcntl(fileno(stdin), F_SETFL, 0);
 141                 in_non_blocking_mode = 0;
 142         }
 143 }
 144
 145 /* Puts stdin terminal in non-blocking mode. */
 146
 147 static void
 148 enter_non_blocking(void)
 149 {
 150         in_non_blocking_mode = 1;
 151         (void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
 152 }
 153
 154 /*
 155  * Signal handler for the window change signal (SIGWINCH).  This just sets a
 156  * flag indicating that the window has changed.
 157  */
 158
 159 static void
 160 window_change_handler(int sig)
 161 {
 162         received_window_change_signal = 1;
 163         signal(SIGWINCH, window_change_handler);
 164 }
 165
 166 /*
 167  * Signal handler for signals that cause the program to terminate.  These
 168  * signals must be trapped to restore terminal modes.
 169  */
 170
 171 static void
 172 signal_handler(int sig)
 173 {
 174         received_signal = sig;
 175         quit_pending = 1;
 176 }
 177
 178 /*
 179  * Returns current time in seconds from Jan 1, 1970 with the maximum
 180  * available resolution.
 181  */
 182
 183 static double
 184 get_current_time(void)
 185 {
 186         struct timeval tv;
 187         gettimeofday(&tv, NULL);
 188         return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
 189 }
 190
 191 /*
 192  * This is called when the interactive is entered.  This checks if there is
 193  * an EOF coming on stdin.  We must check this explicitly, as select() does
 194  * not appear to wake up when redirecting from /dev/null.
 195  */
 196
 197 static void
 198 client_check_initial_eof_on_stdin(void)
 199 {
 200         int len;
 201         char buf[1];
 202
 203         /*
 204          * If standard input is to be "redirected from /dev/null", we simply
 205          * mark that we have seen an EOF and send an EOF message to the
 206          * server. Otherwise, we try to read a single character; it appears
 207          * that for some files, such /dev/null, select() never wakes up for
 208          * read for this descriptor, which means that we never get EOF.  This
 209          * way we will get the EOF if stdin comes from /dev/null or similar.
 210          */
 211         if (stdin_null_flag) {
 212                 /* Fake EOF on stdin. */
 213                 debug("Sending eof.");
 214                 stdin_eof = 1;
 215                 packet_start(SSH_CMSG_EOF);
 216                 packet_send();
 217         } else {
 218                 enter_non_blocking();
 219
 220                 /* Check for immediate EOF on stdin. */
 221                 len = read(fileno(stdin), buf, 1);
 222                 if (len == 0) {
 223                         /* EOF.  Record that we have seen it and send EOF to server. */
 224                         debug("Sending eof.");
 225                         stdin_eof = 1;
 226                         packet_start(SSH_CMSG_EOF);
 227                         packet_send();
 228                 } else if (len > 0) {
 229                         /*
 230                          * Got data.  We must store the data in the buffer,
 231                          * and also process it as an escape character if
 232                          * appropriate.
 233                          */
 234                         if ((u_char) buf[0] == escape_char)
 235                                 escape_pending = 1;
 236                         else
 237                                 buffer_append(&stdin_buffer, buf, 1);
 238                 }
 239                 leave_non_blocking();
 240         }
 241 }
 242
 243
 244 /*
 245  * Make packets from buffered stdin data, and buffer them for sending to the
 246  * connection.
 247  */
 248
 249 static void
 250 client_make_packets_from_stdin_data(void)
 251 {
 252         u_int len;
 253
 254         /* Send buffered stdin data to the server. */
 255         while (buffer_len(&stdin_buffer) > 0 &&
 256             packet_not_very_much_data_to_write()) {
 257                 len = buffer_len(&stdin_buffer);
 258                 /* Keep the packets at reasonable size. */
 259                 if (len > packet_get_maxsize())
 260                         len = packet_get_maxsize();
 261                 packet_start(SSH_CMSG_STDIN_DATA);
 262                 packet_put_string(buffer_ptr(&stdin_buffer), len);
 263                 packet_send();
 264                 buffer_consume(&stdin_buffer, len);
 265                 stdin_bytes += len;
 266                 /* If we have a pending EOF, send it now. */
 267                 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
 268                         packet_start(SSH_CMSG_EOF);
 269                         packet_send();
 270                 }
 271         }
 272 }
 273
 274 /*
 275  * Checks if the client window has changed, and sends a packet about it to
 276  * the server if so.  The actual change is detected elsewhere (by a software
 277  * interrupt on Unix); this just checks the flag and sends a message if
 278  * appropriate.
 279  */
 280
 281 static void
 282 client_check_window_change(void)
 283 {
 284         struct winsize ws;
 285
 286         if (! received_window_change_signal)
 287                 return;
 288         /** XXX race */
 289         received_window_change_signal = 0;
 290
 291         if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
 292                 return;
 293
 294         debug2("client_check_window_change: changed");
 295
 296         if (compat20) {
 297                 channel_request_start(session_ident, "window-change", 0);
 298                 packet_put_int(ws.ws_col);
 299                 packet_put_int(ws.ws_row);
 300                 packet_put_int(ws.ws_xpixel);
 301                 packet_put_int(ws.ws_ypixel);
 302                 packet_send();
 303         } else {
 304                 packet_start(SSH_CMSG_WINDOW_SIZE);
 305                 packet_put_int(ws.ws_row);
 306                 packet_put_int(ws.ws_col);
 307                 packet_put_int(ws.ws_xpixel);
 308                 packet_put_int(ws.ws_ypixel);
 309                 packet_send();
 310         }
 311 }
 312
 313 /*
 314  * Waits until the client can do something (some data becomes available on
 315  * one of the file descriptors).
 316  */
 317
 318 static void
 319 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
 320     int *maxfdp, int *nallocp, int rekeying)
 321 {
 322         /* Add any selections by the channel mechanism. */
 323         channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
 324
 325         if (!compat20) {
 326                 /* Read from the connection, unless our buffers are full. */
 327                 if (buffer_len(&stdout_buffer) < buffer_high &&
 328                     buffer_len(&stderr_buffer) < buffer_high &&
 329                     channel_not_very_much_buffered_data())
 330                         FD_SET(connection_in, *readsetp);
 331                 /*
 332                  * Read from stdin, unless we have seen EOF or have very much
 333                  * buffered data to send to the server.
 334                  */
 335                 if (!stdin_eof && packet_not_very_much_data_to_write())
 336                         FD_SET(fileno(stdin), *readsetp);
 337
 338                 /* Select stdout/stderr if have data in buffer. */
 339                 if (buffer_len(&stdout_buffer) > 0)
 340                         FD_SET(fileno(stdout), *writesetp);
 341                 if (buffer_len(&stderr_buffer) > 0)
 342                         FD_SET(fileno(stderr), *writesetp);
 343         } else {
 344                 /* channel_prepare_select could have closed the last channel */
 345                 if (session_closed && !channel_still_open() &&
 346                     !packet_have_data_to_write()) {
 347                         /* clear mask since we did not call select() */
 348                         memset(*readsetp, 0, *nallocp);
 349                         memset(*writesetp, 0, *nallocp);
 350                         return;
 351                 } else {
 352                         FD_SET(connection_in, *readsetp);
 353                 }
 354         }
 355
 356         /* Select server connection if have data to write to the server. */
 357         if (packet_have_data_to_write())
 358                 FD_SET(connection_out, *writesetp);
 359
 360         /*
 361          * Wait for something to happen.  This will suspend the process until
 362          * some selected descriptor can be read, written, or has some other
 363          * event pending. Note: if you want to implement SSH_MSG_IGNORE
 364          * messages to fool traffic analysis, this might be the place to do
 365          * it: just have a random timeout for the select, and send a random
 366          * SSH_MSG_IGNORE packet when the timeout expires.
 367          */
 368
 369         if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) {
 370                 char buf[100];
 371
 372                 /*
 373                  * We have to clear the select masks, because we return.
 374                  * We have to return, because the mainloop checks for the flags
 375                  * set by the signal handlers.
 376                  */
 377                 memset(*readsetp, 0, *nallocp);
 378                 memset(*writesetp, 0, *nallocp);
 379
 380                 if (errno == EINTR)
 381                         return;
 382                 /* Note: we might still have data in the buffers. */
 383                 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
 384                 buffer_append(&stderr_buffer, buf, strlen(buf));
 385                 quit_pending = 1;
 386         }
 387 }
 388
 389 static void
 390 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
 391 {
 392         struct winsize oldws, newws;
 393
 394         /* Flush stdout and stderr buffers. */
 395         if (buffer_len(bout) > 0)
 396                 atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
 397         if (buffer_len(berr) > 0)
 398                 atomicio(vwrite, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
 399
 400         leave_raw_mode();
 401
 402         /*
 403          * Free (and clear) the buffer to reduce the amount of data that gets
 404          * written to swap.
 405          */
 406         buffer_free(bin);
 407         buffer_free(bout);
 408         buffer_free(berr);
 409
 410         /* Save old window size. */
 411         ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
 412
 413         /* Send the suspend signal to the program itself. */
 414         kill(getpid(), SIGTSTP);
 415
 416         /* Check if the window size has changed. */
 417         if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 &&
 418             (oldws.ws_row != newws.ws_row ||
 419             oldws.ws_col != newws.ws_col ||
 420             oldws.ws_xpixel != newws.ws_xpixel ||
 421             oldws.ws_ypixel != newws.ws_ypixel))
 422                 received_window_change_signal = 1;
 423
 424         /* OK, we have been continued by the user. Reinitialize buffers. */
 425         buffer_init(bin);
 426         buffer_init(bout);
 427         buffer_init(berr);
 428
 429         enter_raw_mode();
 430 }
 431
 432 static void
 433 client_process_net_input(fd_set * readset)
 434 {
 435         int len;
 436         char buf[8192];
 437
 438         /*
 439          * Read input from the server, and add any such data to the buffer of
 440          * the packet subsystem.
 441          */
 442         if (FD_ISSET(connection_in, readset)) {
 443                 /* Read as much as possible. */
 444                 len = read(connection_in, buf, sizeof(buf));
 445                 if (len == 0) {
 446                         /* Received EOF.  The remote host has closed the connection. */
 447                         snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
 448                                  host);
 449                         buffer_append(&stderr_buffer, buf, strlen(buf));
 450                         quit_pending = 1;
 451                         return;
 452                 }
 453                 /*
 454                  * There is a kernel bug on Solaris that causes select to
 455                  * sometimes wake up even though there is no data available.
 456                  */
 457                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
 458                         len = 0;
 459
 460                 if (len < 0) {
 461                         /* An error has encountered.  Perhaps there is a network problem. */
 462                         snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
 463                                  host, strerror(errno));
 464                         buffer_append(&stderr_buffer, buf, strlen(buf));
 465                         quit_pending = 1;
 466                         return;
 467                 }
 468                 packet_process_incoming(buf, len);
 469         }
 470 }
 471
 472 static void
 473 process_cmdline(void)
 474 {
 475         void (*handler)(int);
 476         char *s, *cmd;
 477         u_short fwd_port, fwd_host_port;
 478         char buf[1024], sfwd_port[6], sfwd_host_port[6];
 479         int local = 0;
 480
 481         leave_raw_mode();
 482         handler = signal(SIGINT, SIG_IGN);
 483         cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
 484         if (s == NULL)
 485                 goto out;
 486         while (*s && isspace(*s))
 487                 s++;
 488         if (*s == 0)
 489                 goto out;
 490         if (strlen(s) < 2 || s[0] != '-' || !(s[1] == 'L' || s[1] == 'R')) {
 491                 logit("Invalid command.");
 492                 goto out;
 493         }
 494         if (s[1] == 'L')
 495                 local = 1;
 496         if (!local && !compat20) {
 497                 logit("Not supported for SSH protocol version 1.");
 498                 goto out;
 499         }
 500         s += 2;
 501         while (*s && isspace(*s))
 502                 s++;
 503
 504         if (sscanf(s, "%5[0-9]:%255[^:]:%5[0-9]",
 505             sfwd_port, buf, sfwd_host_port) != 3 &&
 506             sscanf(s, "%5[0-9]/%255[^/]/%5[0-9]",
 507             sfwd_port, buf, sfwd_host_port) != 3) {
 508                 logit("Bad forwarding specification.");
 509                 goto out;
 510         }
 511         if ((fwd_port = a2port(sfwd_port)) == 0 ||
 512             (fwd_host_port = a2port(sfwd_host_port)) == 0) {
 513                 logit("Bad forwarding port(s).");
 514                 goto out;
 515         }
 516         if (local) {
 517                 if (channel_setup_local_fwd_listener(fwd_port, buf,
 518                     fwd_host_port, options.gateway_ports) < 0) {
 519                         logit("Port forwarding failed.");
 520                         goto out;
 521                 }
 522         } else
 523                 channel_request_remote_forwarding(fwd_port, buf,
 524                     fwd_host_port);
 525         logit("Forwarding port.");
 526 out:
 527         signal(SIGINT, handler);
 528         enter_raw_mode();
 529         if (cmd)
 530                 xfree(cmd);
 531 }
 532
 533 /* process the characters one by one */
 534 static int
 535 process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
 536 {
 537         char string[1024];
 538         pid_t pid;
 539         int bytes = 0;
 540         u_int i;
 541         u_char ch;
 542         char *s;
 543
 544         for (i = 0; i < len; i++) {
 545                 /* Get one character at a time. */
 546                 ch = buf[i];
 547
 548                 if (escape_pending) {
 549                         /* We have previously seen an escape character. */
 550                         /* Clear the flag now. */
 551                         escape_pending = 0;
 552
 553                         /* Process the escaped character. */
 554                         switch (ch) {
 555                         case '.':
 556                                 /* Terminate the connection. */
 557                                 snprintf(string, sizeof string, "%c.\r\n", escape_char);
 558                                 buffer_append(berr, string, strlen(string));
 559
 560                                 quit_pending = 1;
 561                                 return -1;
 562
 563                         case 'Z' - 64:
 564                                 /* Suspend the program. */
 565                                 /* Print a message to that effect to the user. */
 566                                 snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
 567                                 buffer_append(berr, string, strlen(string));
 568
 569                                 /* Restore terminal modes and suspend. */
 570                                 client_suspend_self(bin, bout, berr);
 571
 572                                 /* We have been continued. */
 573                                 continue;
 574
 575                         case 'B':
 576                                 if (compat20) {
 577                                         snprintf(string, sizeof string,
 578                                             "%cB\r\n", escape_char);
 579                                         buffer_append(berr, string,
 580                                             strlen(string));
 581                                         channel_request_start(session_ident,
 582                                             "break", 0);
 583                                         packet_put_int(1000);
 584                                         packet_send();
 585                                 }
 586                                 continue;
 587
 588                         case 'R':
 589                                 if (compat20) {
 590                                         if (datafellows & SSH_BUG_NOREKEY)
 591                                                 logit("Server does not support re-keying");
 592                                         else
 593                                                 need_rekeying = 1;
 594                                 }
 595                                 continue;
 596
 597                         case '&':
 598                                 /*
 599                                  * Detach the program (continue to serve connections,
 600                                  * but put in background and no more new connections).
 601                                  */
 602                                 /* Restore tty modes. */
 603                                 leave_raw_mode();
 604
 605                                 /* Stop listening for new connections. */
 606                                 channel_stop_listening();
 607
 608                                 snprintf(string, sizeof string,
 609                                     "%c& [backgrounded]\n", escape_char);
 610                                 buffer_append(berr, string, strlen(string));
 611
 612                                 /* Fork into background. */
 613                                 pid = fork();
 614                                 if (pid < 0) {
 615                                         error("fork: %.100s", strerror(errno));
 616                                         continue;
 617                                 }
 618                                 if (pid != 0) { /* This is the parent. */
 619                                         /* The parent just exits. */
 620                                         exit(0);
 621                                 }
 622                                 /* The child continues serving connections. */
 623                                 if (compat20) {
 624                                         buffer_append(bin, "\004", 1);
 625                                         /* fake EOF on stdin */
 626                                         return -1;
 627                                 } else if (!stdin_eof) {
 628                                         /*
 629                                          * Sending SSH_CMSG_EOF alone does not always appear
 630                                          * to be enough.  So we try to send an EOF character
 631                                          * first.
 632                                          */
 633                                         packet_start(SSH_CMSG_STDIN_DATA);
 634                                         packet_put_string("\004", 1);
 635                                         packet_send();
 636                                         /* Close stdin. */
 637                                         stdin_eof = 1;
 638                                         if (buffer_len(bin) == 0) {
 639                                                 packet_start(SSH_CMSG_EOF);
 640                                                 packet_send();
 641                                         }
 642                                 }
 643                                 continue;
 644
 645                         case '?':
 646                                 snprintf(string, sizeof string,
 647 "%c?\r\n\
 648 Supported escape sequences:\r\n\
 649 %c.  - terminate connection\r\n\
 650 %cB  - send a BREAK to the remote system\r\n\
 651 %cC  - open a command line\r\n\
 652 %cR  - Request rekey (SSH protocol 2 only)\r\n\
 653 %c^Z - suspend ssh\r\n\
 654 %c#  - list forwarded connections\r\n\
 655 %c&  - background ssh (when waiting for connections to terminate)\r\n\
 656 %c?  - this message\r\n\
 657 %c%c  - send the escape character by typing it twice\r\n\
 658 (Note that escapes are only recognized immediately after newline.)\r\n",
 659                                     escape_char, escape_char, escape_char, escape_char,
 660                                     escape_char, escape_char, escape_char, escape_char,
 661                                     escape_char, escape_char, escape_char);
 662                                 buffer_append(berr, string, strlen(string));
 663                                 continue;
 664
 665                         case '#':
 666                                 snprintf(string, sizeof string, "%c#\r\n", escape_char);
 667                                 buffer_append(berr, string, strlen(string));
 668                                 s = channel_open_message();
 669                                 buffer_append(berr, s, strlen(s));
 670                                 xfree(s);
 671                                 continue;
 672
 673                         case 'C':
 674                                 process_cmdline();
 675                                 continue;
 676
 677                         default:
 678                                 if (ch != escape_char) {
 679                                         buffer_put_char(bin, escape_char);
 680                                         bytes++;
 681                                 }
 682                                 /* Escaped characters fall through here */
 683                                 break;
 684                         }
 685                 } else {
 686                         /*
 687                          * The previous character was not an escape char. Check if this
 688                          * is an escape.
 689                          */
 690                         if (last_was_cr && ch == escape_char) {
 691                                 /* It is. Set the flag and continue to next character. */
 692                                 escape_pending = 1;
 693                                 continue;
 694                         }
 695                 }
 696
 697                 /*
 698                  * Normal character.  Record whether it was a newline,
 699                  * and append it to the buffer.
 700                  */
 701                 last_was_cr = (ch == '\r' || ch == '\n');
 702                 buffer_put_char(bin, ch);
 703                 bytes++;
 704         }
 705         return bytes;
 706 }
 707
 708 static void
 709 client_process_input(fd_set * readset)
 710 {
 711         int len;
 712         char buf[8192];
 713
 714         /* Read input from stdin. */
 715         if (FD_ISSET(fileno(stdin), readset)) {
 716                 /* Read as much as possible. */
 717                 len = read(fileno(stdin), buf, sizeof(buf));
 718                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
 719                         return;         /* we'll try again later */
 720                 if (len <= 0) {
 721                         /*
 722                          * Received EOF or error.  They are treated
 723                          * similarly, except that an error message is printed
 724                          * if it was an error condition.
 725                          */
 726                         if (len < 0) {
 727                                 snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
 728                                 buffer_append(&stderr_buffer, buf, strlen(buf));
 729                         }
 730                         /* Mark that we have seen EOF. */
 731                         stdin_eof = 1;
 732                         /*
 733                          * Send an EOF message to the server unless there is
 734                          * data in the buffer.  If there is data in the
 735                          * buffer, no message will be sent now.  Code
 736                          * elsewhere will send the EOF when the buffer
 737                          * becomes empty if stdin_eof is set.
 738                          */
 739                         if (buffer_len(&stdin_buffer) == 0) {
 740                                 packet_start(SSH_CMSG_EOF);
 741                                 packet_send();
 742                         }
 743                 } else if (escape_char == SSH_ESCAPECHAR_NONE) {
 744                         /*
 745                          * Normal successful read, and no escape character.
 746                          * Just append the data to buffer.
 747                          */
 748                         buffer_append(&stdin_buffer, buf, len);
 749                 } else {
 750                         /*
 751                          * Normal, successful read.  But we have an escape character
 752                          * and have to process the characters one by one.
 753                          */
 754                         if (process_escapes(&stdin_buffer, &stdout_buffer,
 755                             &stderr_buffer, buf, len) == -1)
 756                                 return;
 757                 }
 758         }
 759 }
 760
 761 static void
 762 client_process_output(fd_set * writeset)
 763 {
 764         int len;
 765         char buf[100];
 766
 767         /* Write buffered output to stdout. */
 768         if (FD_ISSET(fileno(stdout), writeset)) {
 769                 /* Write as much data as possible. */
 770                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
 771                     buffer_len(&stdout_buffer));
 772                 if (len <= 0) {
 773                         if (errno == EINTR || errno == EAGAIN)
 774                                 len = 0;
 775                         else {
 776                                 /*
 777                                  * An error or EOF was encountered.  Put an
 778                                  * error message to stderr buffer.
 779                                  */
 780                                 snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
 781                                 buffer_append(&stderr_buffer, buf, strlen(buf));
 782                                 quit_pending = 1;
 783                                 return;
 784                         }
 785                 }
 786                 /* Consume printed data from the buffer. */
 787                 buffer_consume(&stdout_buffer, len);
 788                 stdout_bytes += len;
 789         }
 790         /* Write buffered output to stderr. */
 791         if (FD_ISSET(fileno(stderr), writeset)) {
 792                 /* Write as much data as possible. */
 793                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
 794                     buffer_len(&stderr_buffer));
 795                 if (len <= 0) {
 796                         if (errno == EINTR || errno == EAGAIN)
 797                                 len = 0;
 798                         else {
 799                                 /* EOF or error, but can't even print error message. */
 800                                 quit_pending = 1;
 801                                 return;
 802                         }
 803                 }
 804                 /* Consume printed characters from the buffer. */
 805                 buffer_consume(&stderr_buffer, len);
 806                 stderr_bytes += len;
 807         }
 808 }
 809
 810 /*
 811  * Get packets from the connection input buffer, and process them as long as
 812  * there are packets available.
 813  *
 814  * Any unknown packets received during the actual
 815  * session cause the session to terminate.  This is
 816  * intended to make debugging easier since no
 817  * confirmations are sent.  Any compatible protocol
 818  * extensions must be negotiated during the
 819  * preparatory phase.
 820  */
 821
 822 static void
 823 client_process_buffered_input_packets(void)
 824 {
 825         dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL);
 826 }
 827
 828 /* scan buf[] for '~' before sending data to the peer */
 829
 830 static int
 831 simple_escape_filter(Channel *c, char *buf, int len)
 832 {
 833         /* XXX we assume c->extended is writeable */
 834         return process_escapes(&c->input, &c->output, &c->extended, buf, len);
 835 }
 836
 837 static void
 838 client_channel_closed(int id, void *arg)
 839 {
 840         if (id != session_ident)
 841                 error("client_channel_closed: id %d != session_ident %d",
 842                     id, session_ident);
 843         channel_cancel_cleanup(id);
 844         session_closed = 1;
 845         leave_raw_mode();
 846 }
 847
 848 /*
 849  * Implements the interactive session with the server.  This is called after
 850  * the user has been authenticated, and a command has been started on the
 851  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
 852  * used as an escape character for terminating or suspending the session.
 853  */
 854
 855 int
 856 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
 857 {
 858         fd_set *readset = NULL, *writeset = NULL;
 859         double start_time, total_time;
 860         int max_fd = 0, max_fd2 = 0, len, rekeying = 0, nalloc = 0;
 861         char buf[100];
 862
 863         debug("Entering interactive session.");
 864
 865         start_time = get_current_time();
 866
 867         /* Initialize variables. */
 868         escape_pending = 0;
 869         last_was_cr = 1;
 870         exit_status = -1;
 871         stdin_eof = 0;
 872         buffer_high = 64 * 1024;
 873         connection_in = packet_get_connection_in();
 874         connection_out = packet_get_connection_out();
 875         max_fd = MAX(connection_in, connection_out);
 876
 877         if (!compat20) {
 878                 /* enable nonblocking unless tty */
 879                 if (!isatty(fileno(stdin)))
 880                         set_nonblock(fileno(stdin));
 881                 if (!isatty(fileno(stdout)))
 882                         set_nonblock(fileno(stdout));
 883                 if (!isatty(fileno(stderr)))
 884                         set_nonblock(fileno(stderr));
 885                 max_fd = MAX(max_fd, fileno(stdin));
 886                 max_fd = MAX(max_fd, fileno(stdout));
 887                 max_fd = MAX(max_fd, fileno(stderr));
 888         }
 889         stdin_bytes = 0;
 890         stdout_bytes = 0;
 891         stderr_bytes = 0;
 892         quit_pending = 0;
 893         escape_char = escape_char_arg;
 894
 895         /* Initialize buffers. */
 896         buffer_init(&stdin_buffer);
 897         buffer_init(&stdout_buffer);
 898         buffer_init(&stderr_buffer);
 899
 900         client_init_dispatch();
 901
 902         /*
 903          * Set signal handlers, (e.g. to restore non-blocking mode)
 904          * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
 905          */
 906         if (signal(SIGINT, SIG_IGN) != SIG_IGN)
 907                 signal(SIGINT, signal_handler);
 908         if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
 909                 signal(SIGQUIT, signal_handler);
 910         if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
 911                 signal(SIGTERM, signal_handler);
 912         if (have_pty)
 913                 signal(SIGWINCH, window_change_handler);
 914
 915         if (have_pty)
 916                 enter_raw_mode();
 917
 918         if (compat20) {
 919                 session_ident = ssh2_chan_id;
 920                 if (escape_char != SSH_ESCAPECHAR_NONE)
 921                         channel_register_filter(session_ident,
 922                             simple_escape_filter);
 923                 if (session_ident != -1)
 924                         channel_register_cleanup(session_ident,
 925                             client_channel_closed);
 926         } else {
 927                 /* Check if we should immediately send eof on stdin. */
 928                 client_check_initial_eof_on_stdin();
 929         }
 930
 931         /* Main loop of the client for the interactive session mode. */
 932         while (!quit_pending) {
 933
 934                 /* Process buffered packets sent by the server. */
 935                 client_process_buffered_input_packets();
 936
 937                 if (compat20 && session_closed && !channel_still_open())
 938                         break;
 939
 940                 rekeying = (xxx_kex != NULL && !xxx_kex->done);
 941
 942                 if (rekeying) {
 943                         debug("rekeying in progress");
 944                 } else {
 945                         /*
 946                          * Make packets of buffered stdin data, and buffer
 947                          * them for sending to the server.
 948                          */
 949                         if (!compat20)
 950                                 client_make_packets_from_stdin_data();
 951
 952                         /*
 953                          * Make packets from buffered channel data, and
 954                          * enqueue them for sending to the server.
 955                          */
 956                         if (packet_not_very_much_data_to_write())
 957                                 channel_output_poll();
 958
 959                         /*
 960                          * Check if the window size has changed, and buffer a
 961                          * message about it to the server if so.
 962                          */
 963                         client_check_window_change();
 964
 965                         if (quit_pending)
 966                                 break;
 967                 }
 968                 /*
 969                  * Wait until we have something to do (something becomes
 970                  * available on one of the descriptors).
 971                  */
 972                 max_fd2 = max_fd;
 973                 client_wait_until_can_do_something(&readset, &writeset,
 974                     &max_fd2, &nalloc, rekeying);
 975
 976                 if (quit_pending)
 977                         break;
 978
 979                 /* Do channel operations unless rekeying in progress. */
 980                 if (!rekeying) {
 981                         channel_after_select(readset, writeset);
 982                         if (need_rekeying || packet_need_rekeying()) {
 983                                 debug("need rekeying");
 984                                 xxx_kex->done = 0;
 985                                 kex_send_kexinit(xxx_kex);
 986                                 need_rekeying = 0;
 987                         }
 988                 }
 989
 990                 /* Buffer input from the connection.  */
 991                 client_process_net_input(readset);
 992
 993                 if (quit_pending)
 994                         break;
 995
 996                 if (!compat20) {
 997                         /* Buffer data from stdin */
 998                         client_process_input(readset);
 999                         /*
1000                          * Process output to stdout and stderr.  Output to
1001                          * the connection is processed elsewhere (above).
1002                          */
1003                         client_process_output(writeset);
1004                 }
1005
1006                 /* Send as much buffered packet data as possible to the sender. */
1007                 if (FD_ISSET(connection_out, writeset))
1008                         packet_write_poll();
1009         }
1010         if (readset)
1011                 xfree(readset);
1012         if (writeset)
1013                 xfree(writeset);
1014
1015         /* Terminate the session. */
1016
1017         /* Stop watching for window change. */
1018         if (have_pty)
1019                 signal(SIGWINCH, SIG_DFL);
1020
1021         channel_free_all();
1022
1023         if (have_pty)
1024                 leave_raw_mode();
1025
1026         /* restore blocking io */
1027         if (!isatty(fileno(stdin)))
1028                 unset_nonblock(fileno(stdin));
1029         if (!isatty(fileno(stdout)))
1030                 unset_nonblock(fileno(stdout));
1031         if (!isatty(fileno(stderr)))
1032                 unset_nonblock(fileno(stderr));
1033
1034         if (received_signal)
1035                 fatal("Killed by signal %d.", (int) received_signal);
1036
1037         /*
1038          * In interactive mode (with pseudo tty) display a message indicating
1039          * that the connection has been closed.
1040          */
1041         if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1042                 snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
1043                 buffer_append(&stderr_buffer, buf, strlen(buf));
1044         }
1045
1046         /* Output any buffered data for stdout. */
1047         while (buffer_len(&stdout_buffer) > 0) {
1048                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1049                     buffer_len(&stdout_buffer));
1050                 if (len <= 0) {
1051                         error("Write failed flushing stdout buffer.");
1052                         break;
1053                 }
1054                 buffer_consume(&stdout_buffer, len);
1055                 stdout_bytes += len;
1056         }
1057
1058         /* Output any buffered data for stderr. */
1059         while (buffer_len(&stderr_buffer) > 0) {
1060                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1061                     buffer_len(&stderr_buffer));
1062                 if (len <= 0) {
1063                         error("Write failed flushing stderr buffer.");
1064                         break;
1065                 }
1066                 buffer_consume(&stderr_buffer, len);
1067                 stderr_bytes += len;
1068         }
1069
1070         /* Clear and free any buffers. */
1071         memset(buf, 0, sizeof(buf));
1072         buffer_free(&stdin_buffer);
1073         buffer_free(&stdout_buffer);
1074         buffer_free(&stderr_buffer);
1075
1076         /* Report bytes transferred, and transfer rates. */
1077         total_time = get_current_time() - start_time;
1078         debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
1079             stdin_bytes, stdout_bytes, stderr_bytes, total_time);
1080         if (total_time > 0)
1081                 debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
1082                     stdin_bytes / total_time, stdout_bytes / total_time,
1083                     stderr_bytes / total_time);
1084
1085         /* Return the exit status of the program. */
1086         debug("Exit status %d", exit_status);
1087         return exit_status;
1088 }
1089
1090 /*********/
1091
1092 static void
1093 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1094 {
1095         u_int data_len;
1096         char *data = packet_get_string(&data_len);
1097         packet_check_eom();
1098         buffer_append(&stdout_buffer, data, data_len);
1099         memset(data, 0, data_len);
1100         xfree(data);
1101 }
1102 static void
1103 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1104 {
1105         u_int data_len;
1106         char *data = packet_get_string(&data_len);
1107         packet_check_eom();
1108         buffer_append(&stderr_buffer, data, data_len);
1109         memset(data, 0, data_len);
1110         xfree(data);
1111 }
1112 static void
1113 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1114 {
1115         exit_status = packet_get_int();
1116         packet_check_eom();
1117         /* Acknowledge the exit. */
1118         packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1119         packet_send();
1120         /*
1121          * Must wait for packet to be sent since we are
1122          * exiting the loop.
1123          */
1124         packet_write_wait();
1125         /* Flag that we want to exit. */
1126         quit_pending = 1;
1127 }
1128 static void
1129 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1130 {
1131         Channel *c = NULL;
1132         int remote_id, sock;
1133
1134         /* Read the remote channel number from the message. */
1135         remote_id = packet_get_int();
1136         packet_check_eom();
1137
1138         /*
1139          * Get a connection to the local authentication agent (this may again
1140          * get forwarded).
1141          */
1142         sock = ssh_get_authentication_socket();
1143
1144         /*
1145          * If we could not connect the agent, send an error message back to
1146          * the server. This should never happen unless the agent dies,
1147          * because authentication forwarding is only enabled if we have an
1148          * agent.
1149          */
1150         if (sock >= 0) {
1151                 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1152                     -1, 0, 0, 0, "authentication agent connection", 1);
1153                 c->remote_id = remote_id;
1154                 c->force_drain = 1;
1155         }
1156         if (c == NULL) {
1157                 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1158                 packet_put_int(remote_id);
1159         } else {
1160                 /* Send a confirmation to the remote host. */
1161                 debug("Forwarding authentication connection.");
1162                 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1163                 packet_put_int(remote_id);
1164                 packet_put_int(c->self);
1165         }
1166         packet_send();
1167 }
1168
1169 static Channel *
1170 client_request_forwarded_tcpip(const char *request_type, int rchan)
1171 {
1172         Channel *c = NULL;
1173         char *listen_address, *originator_address;
1174         int listen_port, originator_port;
1175         int sock;
1176
1177         /* Get rest of the packet */
1178         listen_address = packet_get_string(NULL);
1179         listen_port = packet_get_int();
1180         originator_address = packet_get_string(NULL);
1181         originator_port = packet_get_int();
1182         packet_check_eom();
1183
1184         debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1185             listen_address, listen_port, originator_address, originator_port);
1186
1187         sock = channel_connect_by_listen_address(listen_port);
1188         if (sock < 0) {
1189                 xfree(originator_address);
1190                 xfree(listen_address);
1191                 return NULL;
1192         }
1193         c = channel_new("forwarded-tcpip",
1194             SSH_CHANNEL_CONNECTING, sock, sock, -1,
1195             CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1196             originator_address, 1);
1197         xfree(originator_address);
1198         xfree(listen_address);
1199         return c;
1200 }
1201
1202 static Channel *
1203 client_request_x11(const char *request_type, int rchan)
1204 {
1205         Channel *c = NULL;
1206         char *originator;
1207         int originator_port;
1208         int sock;
1209
1210         if (!options.forward_x11) {
1211                 error("Warning: ssh server tried X11 forwarding.");
1212                 error("Warning: this is probably a break in attempt by a malicious server.");
1213                 return NULL;
1214         }
1215         originator = packet_get_string(NULL);
1216         if (datafellows & SSH_BUG_X11FWD) {
1217                 debug2("buggy server: x11 request w/o originator_port");
1218                 originator_port = 0;
1219         } else {
1220                 originator_port = packet_get_int();
1221         }
1222         packet_check_eom();
1223         /* XXX check permission */
1224         debug("client_request_x11: request from %s %d", originator,
1225             originator_port);
1226         xfree(originator);
1227         sock = x11_connect_display();
1228         if (sock < 0)
1229                 return NULL;
1230         c = channel_new("x11",
1231             SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1232             CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1233         c->force_drain = 1;
1234         return c;
1235 }
1236
1237 static Channel *
1238 client_request_agent(const char *request_type, int rchan)
1239 {
1240         Channel *c = NULL;
1241         int sock;
1242
1243         if (!options.forward_agent) {
1244                 error("Warning: ssh server tried agent forwarding.");
1245                 error("Warning: this is probably a break in attempt by a malicious server.");
1246                 return NULL;
1247         }
1248         sock =  ssh_get_authentication_socket();
1249         if (sock < 0)
1250                 return NULL;
1251         c = channel_new("authentication agent connection",
1252             SSH_CHANNEL_OPEN, sock, sock, -1,
1253             CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1254             "authentication agent connection", 1);
1255         c->force_drain = 1;
1256         return c;
1257 }
1258
1259 /* XXXX move to generic input handler */
1260 static void
1261 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1262 {
1263         Channel *c = NULL;
1264         char *ctype;
1265         int rchan;
1266         u_int rmaxpack, rwindow, len;
1267
1268         ctype = packet_get_string(&len);
1269         rchan = packet_get_int();
1270         rwindow = packet_get_int();
1271         rmaxpack = packet_get_int();
1272
1273         debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1274             ctype, rchan, rwindow, rmaxpack);
1275
1276         if (strcmp(ctype, "forwarded-tcpip") == 0) {
1277                 c = client_request_forwarded_tcpip(ctype, rchan);
1278         } else if (strcmp(ctype, "x11") == 0) {
1279                 c = client_request_x11(ctype, rchan);
1280         } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1281                 c = client_request_agent(ctype, rchan);
1282         }
1283 /* XXX duplicate : */
1284         if (c != NULL) {
1285                 debug("confirm %s", ctype);
1286                 c->remote_id = rchan;
1287                 c->remote_window = rwindow;
1288                 c->remote_maxpacket = rmaxpack;
1289                 if (c->type != SSH_CHANNEL_CONNECTING) {
1290                         packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1291                         packet_put_int(c->remote_id);
1292                         packet_put_int(c->self);
1293                         packet_put_int(c->local_window);
1294                         packet_put_int(c->local_maxpacket);
1295                         packet_send();
1296                 }
1297         } else {
1298                 debug("failure %s", ctype);
1299                 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1300                 packet_put_int(rchan);
1301                 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1302                 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1303                         packet_put_cstring("open failed");
1304                         packet_put_cstring("");
1305                 }
1306                 packet_send();
1307         }
1308         xfree(ctype);
1309 }
1310 static void
1311 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1312 {
1313         Channel *c = NULL;
1314         int id, reply, success = 0;
1315         char *rtype;
1316
1317         id = packet_get_int();
1318         rtype = packet_get_string(NULL);
1319         reply = packet_get_char();
1320
1321         debug("client_input_channel_req: channel %d rtype %s reply %d",
1322             id, rtype, reply);
1323
1324         if (session_ident == -1) {
1325                 error("client_input_channel_req: no channel %d", session_ident);
1326         } else if (id != session_ident) {
1327                 error("client_input_channel_req: channel %d: wrong channel: %d",
1328                     session_ident, id);
1329         }
1330         c = channel_lookup(id);
1331         if (c == NULL) {
1332                 error("client_input_channel_req: channel %d: unknown channel", id);
1333         } else if (strcmp(rtype, "exit-status") == 0) {
1334                 success = 1;
1335                 exit_status = packet_get_int();
1336                 packet_check_eom();
1337         }
1338         if (reply) {
1339                 packet_start(success ?
1340                     SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1341                 packet_put_int(c->remote_id);
1342                 packet_send();
1343         }
1344         xfree(rtype);
1345 }
1346 static void
1347 client_input_global_request(int type, u_int32_t seq, void *ctxt)
1348 {
1349         char *rtype;
1350         int want_reply;
1351         int success = 0;
1352
1353         rtype = packet_get_string(NULL);
1354         want_reply = packet_get_char();
1355         debug("client_input_global_request: rtype %s want_reply %d", rtype, want_reply);
1356         if (want_reply) {
1357                 packet_start(success ?
1358                     SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1359                 packet_send();
1360                 packet_write_wait();
1361         }
1362         xfree(rtype);
1363 }
1364
1365 static void
1366 client_init_dispatch_20(void)
1367 {
1368         dispatch_init(&dispatch_protocol_error);
1369
1370         dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1371         dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1372         dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1373         dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1374         dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1375         dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1376         dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1377         dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1378         dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1379         dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1380
1381         /* rekeying */
1382         dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1383
1384         /* global request reply messages */
1385         dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
1386         dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1387 }
1388 static void
1389 client_init_dispatch_13(void)
1390 {
1391         dispatch_init(NULL);
1392         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1393         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1394         dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1395         dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1396         dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1397         dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1398         dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
1399         dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
1400         dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1401
1402         dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1403             &client_input_agent_open : &deny_input_open);
1404         dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
1405             &x11_input_open : &deny_input_open);
1406 }
1407 static void
1408 client_init_dispatch_15(void)
1409 {
1410         client_init_dispatch_13();
1411         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1412         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
1413 }
1414 static void
1415 client_init_dispatch(void)
1416 {
1417         if (compat20)
1418                 client_init_dispatch_20();
1419         else if (compat13)
1420                 client_init_dispatch_13();
1421         else
1422                 client_init_dispatch_15();
1423 }
1424
1425 /* client specific fatal cleanup */
1426 void
1427 cleanup_exit(int i)
1428 {
1429         leave_raw_mode();
1430         leave_non_blocking();
1431         _exit(i);
1432 }