openssh/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 1.112 2003/06/28 16:23:06 deraadt 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                 fatal_remove_cleanup((void (*) (void *)) leave_non_blocking, NULL);
 143         }
 144 }
 145
 146 /* Puts stdin terminal in non-blocking mode. */
 147
 148 static void
 149 enter_non_blocking(void)
 150 {
 151         in_non_blocking_mode = 1;
 152         (void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
 153         fatal_add_cleanup((void (*) (void *)) leave_non_blocking, NULL);
 154 }
 155
 156 /*
 157  * Signal handler for the window change signal (SIGWINCH).  This just sets a
 158  * flag indicating that the window has changed.
 159  */
 160
 161 static void
 162 window_change_handler(int sig)
 163 {
 164         received_window_change_signal = 1;
 165         signal(SIGWINCH, window_change_handler);
 166 }
 167
 168 /*
 169  * Signal handler for signals that cause the program to terminate.  These
 170  * signals must be trapped to restore terminal modes.
 171  */
 172
 173 static void
 174 signal_handler(int sig)
 175 {
 176         received_signal = sig;
 177         quit_pending = 1;
 178 }
 179
 180 /*
 181  * Returns current time in seconds from Jan 1, 1970 with the maximum
 182  * available resolution.
 183  */
 184
 185 static double
 186 get_current_time(void)
 187 {
 188         struct timeval tv;
 189         gettimeofday(&tv, NULL);
 190         return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
 191 }
 192
 193 /*
 194  * This is called when the interactive is entered.  This checks if there is
 195  * an EOF coming on stdin.  We must check this explicitly, as select() does
 196  * not appear to wake up when redirecting from /dev/null.
 197  */
 198
 199 static void
 200 client_check_initial_eof_on_stdin(void)
 201 {
 202         int len;
 203         char buf[1];
 204
 205         /*
 206          * If standard input is to be "redirected from /dev/null", we simply
 207          * mark that we have seen an EOF and send an EOF message to the
 208          * server. Otherwise, we try to read a single character; it appears
 209          * that for some files, such /dev/null, select() never wakes up for
 210          * read for this descriptor, which means that we never get EOF.  This
 211          * way we will get the EOF if stdin comes from /dev/null or similar.
 212          */
 213         if (stdin_null_flag) {
 214                 /* Fake EOF on stdin. */
 215                 debug("Sending eof.");
 216                 stdin_eof = 1;
 217                 packet_start(SSH_CMSG_EOF);
 218                 packet_send();
 219         } else {
 220                 enter_non_blocking();
 221
 222                 /* Check for immediate EOF on stdin. */
 223                 len = read(fileno(stdin), buf, 1);
 224                 if (len == 0) {
 225                         /* EOF.  Record that we have seen it and send EOF to server. */
 226                         debug("Sending eof.");
 227                         stdin_eof = 1;
 228                         packet_start(SSH_CMSG_EOF);
 229                         packet_send();
 230                 } else if (len > 0) {
 231                         /*
 232                          * Got data.  We must store the data in the buffer,
 233                          * and also process it as an escape character if
 234                          * appropriate.
 235                          */
 236                         if ((u_char) buf[0] == escape_char)
 237                                 escape_pending = 1;
 238                         else
 239                                 buffer_append(&stdin_buffer, buf, 1);
 240                 }
 241                 leave_non_blocking();
 242         }
 243 }
 244
 245
 246 /*
 247  * Make packets from buffered stdin data, and buffer them for sending to the
 248  * connection.
 249  */
 250
 251 static void
 252 client_make_packets_from_stdin_data(void)
 253 {
 254         u_int len;
 255
 256         /* Send buffered stdin data to the server. */
 257         while (buffer_len(&stdin_buffer) > 0 &&
 258             packet_not_very_much_data_to_write()) {
 259                 len = buffer_len(&stdin_buffer);
 260                 /* Keep the packets at reasonable size. */
 261                 if (len > packet_get_maxsize())
 262                         len = packet_get_maxsize();
 263                 packet_start(SSH_CMSG_STDIN_DATA);
 264                 packet_put_string(buffer_ptr(&stdin_buffer), len);
 265                 packet_send();
 266                 buffer_consume(&stdin_buffer, len);
 267                 stdin_bytes += len;
 268                 /* If we have a pending EOF, send it now. */
 269                 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
 270                         packet_start(SSH_CMSG_EOF);
 271                         packet_send();
 272                 }
 273         }
 274 }
 275
 276 /*
 277  * Checks if the client window has changed, and sends a packet about it to
 278  * the server if so.  The actual change is detected elsewhere (by a software
 279  * interrupt on Unix); this just checks the flag and sends a message if
 280  * appropriate.
 281  */
 282
 283 static void
 284 client_check_window_change(void)
 285 {
 286         struct winsize ws;
 287
 288         if (! received_window_change_signal)
 289                 return;
 290         /** XXX race */
 291         received_window_change_signal = 0;
 292
 293         if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
 294                 return;
 295
 296         debug2("client_check_window_change: changed");
 297
 298         if (compat20) {
 299                 channel_request_start(session_ident, "window-change", 0);
 300                 packet_put_int(ws.ws_col);
 301                 packet_put_int(ws.ws_row);
 302                 packet_put_int(ws.ws_xpixel);
 303                 packet_put_int(ws.ws_ypixel);
 304                 packet_send();
 305         } else {
 306                 packet_start(SSH_CMSG_WINDOW_SIZE);
 307                 packet_put_int(ws.ws_row);
 308                 packet_put_int(ws.ws_col);
 309                 packet_put_int(ws.ws_xpixel);
 310                 packet_put_int(ws.ws_ypixel);
 311                 packet_send();
 312         }
 313 }
 314
 315 /*
 316  * Waits until the client can do something (some data becomes available on
 317  * one of the file descriptors).
 318  */
 319
 320 static void
 321 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
 322     int *maxfdp, int *nallocp, int rekeying)
 323 {
 324         /* Add any selections by the channel mechanism. */
 325         channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
 326
 327         if (!compat20) {
 328                 /* Read from the connection, unless our buffers are full. */
 329                 if (buffer_len(&stdout_buffer) < buffer_high &&
 330                     buffer_len(&stderr_buffer) < buffer_high &&
 331                     channel_not_very_much_buffered_data())
 332                         FD_SET(connection_in, *readsetp);
 333                 /*
 334                  * Read from stdin, unless we have seen EOF or have very much
 335                  * buffered data to send to the server.
 336                  */
 337                 if (!stdin_eof && packet_not_very_much_data_to_write())
 338                         FD_SET(fileno(stdin), *readsetp);
 339
 340                 /* Select stdout/stderr if have data in buffer. */
 341                 if (buffer_len(&stdout_buffer) > 0)
 342                         FD_SET(fileno(stdout), *writesetp);
 343                 if (buffer_len(&stderr_buffer) > 0)
 344                         FD_SET(fileno(stderr), *writesetp);
 345         } else {
 346                 /* channel_prepare_select could have closed the last channel */
 347                 if (session_closed && !channel_still_open() &&
 348                     !packet_have_data_to_write()) {
 349                         /* clear mask since we did not call select() */
 350                         memset(*readsetp, 0, *nallocp);
 351                         memset(*writesetp, 0, *nallocp);
 352                         return;
 353                 } else {
 354                         FD_SET(connection_in, *readsetp);
 355                 }
 356         }
 357
 358         /* Select server connection if have data to write to the server. */
 359         if (packet_have_data_to_write())
 360                 FD_SET(connection_out, *writesetp);
 361
 362         /*
 363          * Wait for something to happen.  This will suspend the process until
 364          * some selected descriptor can be read, written, or has some other
 365          * event pending. Note: if you want to implement SSH_MSG_IGNORE
 366          * messages to fool traffic analysis, this might be the place to do
 367          * it: just have a random timeout for the select, and send a random
 368          * SSH_MSG_IGNORE packet when the timeout expires.
 369          */
 370
 371         if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) {
 372                 char buf[100];
 373
 374                 /*
 375                  * We have to clear the select masks, because we return.
 376                  * We have to return, because the mainloop checks for the flags
 377                  * set by the signal handlers.
 378                  */
 379                 memset(*readsetp, 0, *nallocp);
 380                 memset(*writesetp, 0, *nallocp);
 381
 382                 if (errno == EINTR)
 383                         return;
 384                 /* Note: we might still have data in the buffers. */
 385                 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
 386                 buffer_append(&stderr_buffer, buf, strlen(buf));
 387                 quit_pending = 1;
 388         }
 389 }
 390
 391 static void
 392 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
 393 {
 394         struct winsize oldws, newws;
 395
 396         /* Flush stdout and stderr buffers. */
 397         if (buffer_len(bout) > 0)
 398                 atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
 399         if (buffer_len(berr) > 0)
 400                 atomicio(vwrite, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
 401
 402         leave_raw_mode();
 403
 404         /*
 405          * Free (and clear) the buffer to reduce the amount of data that gets
 406          * written to swap.
 407          */
 408         buffer_free(bin);
 409         buffer_free(bout);
 410         buffer_free(berr);
 411
 412         /* Save old window size. */
 413         ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
 414
 415         /* Send the suspend signal to the program itself. */
 416         kill(getpid(), SIGTSTP);
 417
 418         /* Check if the window size has changed. */
 419         if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 &&
 420             (oldws.ws_row != newws.ws_row ||
 421             oldws.ws_col != newws.ws_col ||
 422             oldws.ws_xpixel != newws.ws_xpixel ||
 423             oldws.ws_ypixel != newws.ws_ypixel))
 424                 received_window_change_signal = 1;
 425
 426         /* OK, we have been continued by the user. Reinitialize buffers. */
 427         buffer_init(bin);
 428         buffer_init(bout);
 429         buffer_init(berr);
 430
 431         enter_raw_mode();
 432 }
 433
 434 static void
 435 client_process_net_input(fd_set * readset)
 436 {
 437         int len;
 438         char buf[8192];
 439
 440         /*
 441          * Read input from the server, and add any such data to the buffer of
 442          * the packet subsystem.
 443          */
 444         if (FD_ISSET(connection_in, readset)) {
 445                 /* Read as much as possible. */
 446                 len = read(connection_in, buf, sizeof(buf));
 447                 if (len == 0) {
 448                         /* Received EOF.  The remote host has closed the connection. */
 449                         snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
 450                                  host);
 451                         buffer_append(&stderr_buffer, buf, strlen(buf));
 452                         quit_pending = 1;
 453                         return;
 454                 }
 455                 /*
 456                  * There is a kernel bug on Solaris that causes select to
 457                  * sometimes wake up even though there is no data available.
 458                  */
 459                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
 460                         len = 0;
 461
 462                 if (len < 0) {
 463                         /* An error has encountered.  Perhaps there is a network problem. */
 464                         snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
 465                                  host, strerror(errno));
 466                         buffer_append(&stderr_buffer, buf, strlen(buf));
 467                         quit_pending = 1;
 468                         return;
 469                 }
 470                 packet_process_incoming(buf, len);
 471         }
 472 }
 473
 474 static void
 475 process_cmdline(void)
 476 {
 477         void (*handler)(int);
 478         char *s, *cmd;
 479         u_short fwd_port, fwd_host_port;
 480         char buf[1024], sfwd_port[6], sfwd_host_port[6];
 481         int local = 0;
 482
 483         leave_raw_mode();
 484         handler = signal(SIGINT, SIG_IGN);
 485         cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
 486         if (s == NULL)
 487                 goto out;
 488         while (*s && isspace(*s))
 489                 s++;
 490         if (*s == 0)
 491                 goto out;
 492         if (strlen(s) < 2 || s[0] != '-' || !(s[1] == 'L' || s[1] == 'R')) {
 493                 logit("Invalid command.");
 494                 goto out;
 495         }
 496         if (s[1] == 'L')
 497                 local = 1;
 498         if (!local && !compat20) {
 499                 logit("Not supported for SSH protocol version 1.");
 500                 goto out;
 501         }
 502         s += 2;
 503         while (*s && isspace(*s))
 504                 s++;
 505
 506         if (sscanf(s, "%5[0-9]:%255[^:]:%5[0-9]",
 507             sfwd_port, buf, sfwd_host_port) != 3 &&
 508             sscanf(s, "%5[0-9]/%255[^/]/%5[0-9]",
 509             sfwd_port, buf, sfwd_host_port) != 3) {
 510                 logit("Bad forwarding specification.");
 511                 goto out;
 512         }
 513         if ((fwd_port = a2port(sfwd_port)) == 0 ||
 514             (fwd_host_port = a2port(sfwd_host_port)) == 0) {
 515                 logit("Bad forwarding port(s).");
 516                 goto out;
 517         }
 518         if (local) {
 519                 if (channel_setup_local_fwd_listener(fwd_port, buf,
 520                     fwd_host_port, options.gateway_ports) < 0) {
 521                         logit("Port forwarding failed.");
 522                         goto out;
 523                 }
 524         } else
 525                 channel_request_remote_forwarding(fwd_port, buf,
 526                     fwd_host_port);
 527         logit("Forwarding port.");
 528 out:
 529         signal(SIGINT, handler);
 530         enter_raw_mode();
 531         if (cmd)
 532                 xfree(cmd);
 533 }
 534
 535 /* process the characters one by one */
 536 static int
 537 process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
 538 {
 539         char string[1024];
 540         pid_t pid;
 541         int bytes = 0;
 542         u_int i;
 543         u_char ch;
 544         char *s;
 545
 546         for (i = 0; i < len; i++) {
 547                 /* Get one character at a time. */
 548                 ch = buf[i];
 549
 550                 if (escape_pending) {
 551                         /* We have previously seen an escape character. */
 552                         /* Clear the flag now. */
 553                         escape_pending = 0;
 554
 555                         /* Process the escaped character. */
 556                         switch (ch) {
 557                         case '.':
 558                                 /* Terminate the connection. */
 559                                 snprintf(string, sizeof string, "%c.\r\n", escape_char);
 560                                 buffer_append(berr, string, strlen(string));
 561
 562                                 quit_pending = 1;
 563                                 return -1;
 564
 565                         case 'Z' - 64:
 566                                 /* Suspend the program. */
 567                                 /* Print a message to that effect to the user. */
 568                                 snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
 569                                 buffer_append(berr, string, strlen(string));
 570
 571                                 /* Restore terminal modes and suspend. */
 572                                 client_suspend_self(bin, bout, berr);
 573
 574                                 /* We have been continued. */
 575                                 continue;
 576
 577                         case 'B':
 578                                 if (compat20) {
 579                                         snprintf(string, sizeof string,
 580                                             "%cB\r\n", escape_char);
 581                                         buffer_append(berr, string,
 582                                             strlen(string));
 583                                         channel_request_start(session_ident,
 584                                             "break", 0);
 585                                         packet_put_int(1000);
 586                                         packet_send();
 587                                 }
 588                                 continue;
 589
 590                         case 'R':
 591                                 if (compat20) {
 592                                         if (datafellows & SSH_BUG_NOREKEY)
 593                                                 logit("Server does not support re-keying");
 594                                         else
 595                                                 need_rekeying = 1;
 596                                 }
 597                                 continue;
 598
 599                         case '&':
 600                                 /*
 601                                  * Detach the program (continue to serve connections,
 602                                  * but put in background and no more new connections).
 603                                  */
 604                                 /* Restore tty modes. */
 605                                 leave_raw_mode();
 606
 607                                 /* Stop listening for new connections. */
 608                                 channel_stop_listening();
 609
 610                                 snprintf(string, sizeof string,
 611                                     "%c& [backgrounded]\n", escape_char);
 612                                 buffer_append(berr, string, strlen(string));
 613
 614                                 /* Fork into background. */
 615                                 pid = fork();
 616                                 if (pid < 0) {
 617                                         error("fork: %.100s", strerror(errno));
 618                                         continue;
 619                                 }
 620                                 if (pid != 0) { /* This is the parent. */
 621                                         /* The parent just exits. */
 622                                         exit(0);
 623                                 }
 624                                 /* The child continues serving connections. */
 625                                 if (compat20) {
 626                                         buffer_append(bin, "\004", 1);
 627                                         /* fake EOF on stdin */
 628                                         return -1;
 629                                 } else if (!stdin_eof) {
 630                                         /*
 631                                          * Sending SSH_CMSG_EOF alone does not always appear
 632                                          * to be enough.  So we try to send an EOF character
 633                                          * first.
 634                                          */
 635                                         packet_start(SSH_CMSG_STDIN_DATA);
 636                                         packet_put_string("\004", 1);
 637                                         packet_send();
 638                                         /* Close stdin. */
 639                                         stdin_eof = 1;
 640                                         if (buffer_len(bin) == 0) {
 641                                                 packet_start(SSH_CMSG_EOF);
 642                                                 packet_send();
 643                                         }
 644                                 }
 645                                 continue;
 646
 647                         case '?':
 648                                 snprintf(string, sizeof string,
 649 "%c?\r\n\
 650 Supported escape sequences:\r\n\
 651 %c.  - terminate connection\r\n\
 652 %cB  - send a BREAK to the remote system\r\n\
 653 %cC  - open a command line\r\n\
 654 %cR  - Request rekey (SSH protocol 2 only)\r\n\
 655 %c^Z - suspend ssh\r\n\
 656 %c#  - list forwarded connections\r\n\
 657 %c&  - background ssh (when waiting for connections to terminate)\r\n\
 658 %c?  - this message\r\n\
 659 %c%c  - send the escape character by typing it twice\r\n\
 660 (Note that escapes are only recognized immediately after newline.)\r\n",
 661                                     escape_char, escape_char, escape_char, escape_char,
 662                                     escape_char, escape_char, escape_char, escape_char,
 663                                     escape_char, escape_char, escape_char);
 664                                 buffer_append(berr, string, strlen(string));
 665                                 continue;
 666
 667                         case '#':
 668                                 snprintf(string, sizeof string, "%c#\r\n", escape_char);
 669                                 buffer_append(berr, string, strlen(string));
 670                                 s = channel_open_message();
 671                                 buffer_append(berr, s, strlen(s));
 672                                 xfree(s);
 673                                 continue;
 674
 675                         case 'C':
 676                                 process_cmdline();
 677                                 continue;
 678
 679                         default:
 680                                 if (ch != escape_char) {
 681                                         buffer_put_char(bin, escape_char);
 682                                         bytes++;
 683                                 }
 684                                 /* Escaped characters fall through here */
 685                                 break;
 686                         }
 687                 } else {
 688                         /*
 689                          * The previous character was not an escape char. Check if this
 690                          * is an escape.
 691                          */
 692                         if (last_was_cr && ch == escape_char) {
 693                                 /* It is. Set the flag and continue to next character. */
 694                                 escape_pending = 1;
 695                                 continue;
 696                         }
 697                 }
 698
 699                 /*
 700                  * Normal character.  Record whether it was a newline,
 701                  * and append it to the buffer.
 702                  */
 703                 last_was_cr = (ch == '\r' || ch == '\n');
 704                 buffer_put_char(bin, ch);
 705                 bytes++;
 706         }
 707         return bytes;
 708 }
 709
 710 static void
 711 client_process_input(fd_set * readset)
 712 {
 713         int len;
 714         char buf[8192];
 715
 716         /* Read input from stdin. */
 717         if (FD_ISSET(fileno(stdin), readset)) {
 718                 /* Read as much as possible. */
 719                 len = read(fileno(stdin), buf, sizeof(buf));
 720                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
 721                         return;         /* we'll try again later */
 722                 if (len <= 0) {
 723                         /*
 724                          * Received EOF or error.  They are treated
 725                          * similarly, except that an error message is printed
 726                          * if it was an error condition.
 727                          */
 728                         if (len < 0) {
 729                                 snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
 730                                 buffer_append(&stderr_buffer, buf, strlen(buf));
 731                         }
 732                         /* Mark that we have seen EOF. */
 733                         stdin_eof = 1;
 734                         /*
 735                          * Send an EOF message to the server unless there is
 736                          * data in the buffer.  If there is data in the
 737                          * buffer, no message will be sent now.  Code
 738                          * elsewhere will send the EOF when the buffer
 739                          * becomes empty if stdin_eof is set.
 740                          */
 741                         if (buffer_len(&stdin_buffer) == 0) {
 742                                 packet_start(SSH_CMSG_EOF);
 743                                 packet_send();
 744                         }
 745                 } else if (escape_char == SSH_ESCAPECHAR_NONE) {
 746                         /*
 747                          * Normal successful read, and no escape character.
 748                          * Just append the data to buffer.
 749                          */
 750                         buffer_append(&stdin_buffer, buf, len);
 751                 } else {
 752                         /*
 753                          * Normal, successful read.  But we have an escape character
 754                          * and have to process the characters one by one.
 755                          */
 756                         if (process_escapes(&stdin_buffer, &stdout_buffer,
 757                             &stderr_buffer, buf, len) == -1)
 758                                 return;
 759                 }
 760         }
 761 }
 762
 763 static void
 764 client_process_output(fd_set * writeset)
 765 {
 766         int len;
 767         char buf[100];
 768
 769         /* Write buffered output to stdout. */
 770         if (FD_ISSET(fileno(stdout), writeset)) {
 771                 /* Write as much data as possible. */
 772                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
 773                     buffer_len(&stdout_buffer));
 774                 if (len <= 0) {
 775                         if (errno == EINTR || errno == EAGAIN)
 776                                 len = 0;
 777                         else {
 778                                 /*
 779                                  * An error or EOF was encountered.  Put an
 780                                  * error message to stderr buffer.
 781                                  */
 782                                 snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
 783                                 buffer_append(&stderr_buffer, buf, strlen(buf));
 784                                 quit_pending = 1;
 785                                 return;
 786                         }
 787                 }
 788                 /* Consume printed data from the buffer. */
 789                 buffer_consume(&stdout_buffer, len);
 790                 stdout_bytes += len;
 791         }
 792         /* Write buffered output to stderr. */
 793         if (FD_ISSET(fileno(stderr), writeset)) {
 794                 /* Write as much data as possible. */
 795                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
 796                     buffer_len(&stderr_buffer));
 797                 if (len <= 0) {
 798                         if (errno == EINTR || errno == EAGAIN)
 799                                 len = 0;
 800                         else {
 801                                 /* EOF or error, but can't even print error message. */
 802                                 quit_pending = 1;
 803                                 return;
 804                         }
 805                 }
 806                 /* Consume printed characters from the buffer. */
 807                 buffer_consume(&stderr_buffer, len);
 808                 stderr_bytes += len;
 809         }
 810 }
 811
 812 /*
 813  * Get packets from the connection input buffer, and process them as long as
 814  * there are packets available.
 815  *
 816  * Any unknown packets received during the actual
 817  * session cause the session to terminate.  This is
 818  * intended to make debugging easier since no
 819  * confirmations are sent.  Any compatible protocol
 820  * extensions must be negotiated during the
 821  * preparatory phase.
 822  */
 823
 824 static void
 825 client_process_buffered_input_packets(void)
 826 {
 827         dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL);
 828 }
 829
 830 /* scan buf[] for '~' before sending data to the peer */
 831
 832 static int
 833 simple_escape_filter(Channel *c, char *buf, int len)
 834 {
 835         /* XXX we assume c->extended is writeable */
 836         return process_escapes(&c->input, &c->output, &c->extended, buf, len);
 837 }
 838
 839 static void
 840 client_channel_closed(int id, void *arg)
 841 {
 842         if (id != session_ident)
 843                 error("client_channel_closed: id %d != session_ident %d",
 844                     id, session_ident);
 845         channel_cancel_cleanup(id);
 846         session_closed = 1;
 847         if (in_raw_mode())
 848                 leave_raw_mode();
 849 }
 850
 851 /*
 852  * Implements the interactive session with the server.  This is called after
 853  * the user has been authenticated, and a command has been started on the
 854  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
 855  * used as an escape character for terminating or suspending the session.
 856  */
 857
 858 int
 859 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
 860 {
 861         fd_set *readset = NULL, *writeset = NULL;
 862         double start_time, total_time;
 863         int max_fd = 0, max_fd2 = 0, len, rekeying = 0, nalloc = 0;
 864         char buf[100];
 865
 866         debug("Entering interactive session.");
 867
 868         start_time = get_current_time();
 869
 870         /* Initialize variables. */
 871         escape_pending = 0;
 872         last_was_cr = 1;
 873         exit_status = -1;
 874         stdin_eof = 0;
 875         buffer_high = 64 * 1024;
 876         connection_in = packet_get_connection_in();
 877         connection_out = packet_get_connection_out();
 878         max_fd = MAX(connection_in, connection_out);
 879
 880         if (!compat20) {
 881                 /* enable nonblocking unless tty */
 882                 if (!isatty(fileno(stdin)))
 883                         set_nonblock(fileno(stdin));
 884                 if (!isatty(fileno(stdout)))
 885                         set_nonblock(fileno(stdout));
 886                 if (!isatty(fileno(stderr)))
 887                         set_nonblock(fileno(stderr));
 888                 max_fd = MAX(max_fd, fileno(stdin));
 889                 max_fd = MAX(max_fd, fileno(stdout));
 890                 max_fd = MAX(max_fd, fileno(stderr));
 891         }
 892         stdin_bytes = 0;
 893         stdout_bytes = 0;
 894         stderr_bytes = 0;
 895         quit_pending = 0;
 896         escape_char = escape_char_arg;
 897
 898         /* Initialize buffers. */
 899         buffer_init(&stdin_buffer);
 900         buffer_init(&stdout_buffer);
 901         buffer_init(&stderr_buffer);
 902
 903         client_init_dispatch();
 904
 905         /*
 906          * Set signal handlers, (e.g. to restore non-blocking mode)
 907          * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
 908          */
 909         if (signal(SIGINT, SIG_IGN) != SIG_IGN)
 910                 signal(SIGINT, signal_handler);
 911         if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
 912                 signal(SIGQUIT, signal_handler);
 913         if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
 914                 signal(SIGTERM, signal_handler);
 915         if (have_pty)
 916                 signal(SIGWINCH, window_change_handler);
 917
 918         if (have_pty)
 919                 enter_raw_mode();
 920
 921         if (compat20) {
 922                 session_ident = ssh2_chan_id;
 923                 if (escape_char != SSH_ESCAPECHAR_NONE)
 924                         channel_register_filter(session_ident,
 925                             simple_escape_filter);
 926                 if (session_ident != -1)
 927                         channel_register_cleanup(session_ident,
 928                             client_channel_closed);
 929         } else {
 930                 /* Check if we should immediately send eof on stdin. */
 931                 client_check_initial_eof_on_stdin();
 932         }
 933
 934         /* Main loop of the client for the interactive session mode. */
 935         while (!quit_pending) {
 936
 937                 /* Process buffered packets sent by the server. */
 938                 client_process_buffered_input_packets();
 939
 940                 if (compat20 && session_closed && !channel_still_open())
 941                         break;
 942
 943                 rekeying = (xxx_kex != NULL && !xxx_kex->done);
 944
 945                 if (rekeying) {
 946                         debug("rekeying in progress");
 947                 } else {
 948                         /*
 949                          * Make packets of buffered stdin data, and buffer
 950                          * them for sending to the server.
 951                          */
 952                         if (!compat20)
 953                                 client_make_packets_from_stdin_data();
 954
 955                         /*
 956                          * Make packets from buffered channel data, and
 957                          * enqueue them for sending to the server.
 958                          */
 959                         if (packet_not_very_much_data_to_write())
 960                                 channel_output_poll();
 961
 962                         /*
 963                          * Check if the window size has changed, and buffer a
 964                          * message about it to the server if so.
 965                          */
 966                         client_check_window_change();
 967
 968                         if (quit_pending)
 969                                 break;
 970                 }
 971                 /*
 972                  * Wait until we have something to do (something becomes
 973                  * available on one of the descriptors).
 974                  */
 975                 max_fd2 = max_fd;
 976                 client_wait_until_can_do_something(&readset, &writeset,
 977                     &max_fd2, &nalloc, rekeying);
 978
 979                 if (quit_pending)
 980                         break;
 981
 982                 /* Do channel operations unless rekeying in progress. */
 983                 if (!rekeying) {
 984                         channel_after_select(readset, writeset);
 985                         if (need_rekeying || packet_need_rekeying()) {
 986                                 debug("need rekeying");
 987                                 xxx_kex->done = 0;
 988                                 kex_send_kexinit(xxx_kex);
 989                                 need_rekeying = 0;
 990                         }
 991                 }
 992
 993                 /* Buffer input from the connection.  */
 994                 client_process_net_input(readset);
 995
 996                 if (quit_pending)
 997                         break;
 998
 999                 if (!compat20) {
1000                         /* Buffer data from stdin */
1001                         client_process_input(readset);
1002                         /*
1003                          * Process output to stdout and stderr.  Output to
1004                          * the connection is processed elsewhere (above).
1005                          */
1006                         client_process_output(writeset);
1007                 }
1008
1009                 /* Send as much buffered packet data as possible to the sender. */
1010                 if (FD_ISSET(connection_out, writeset))
1011                         packet_write_poll();
1012         }
1013         if (readset)
1014                 xfree(readset);
1015         if (writeset)
1016                 xfree(writeset);
1017
1018         /* Terminate the session. */
1019
1020         /* Stop watching for window change. */
1021         if (have_pty)
1022                 signal(SIGWINCH, SIG_DFL);
1023
1024         channel_free_all();
1025
1026         if (have_pty)
1027                 leave_raw_mode();
1028
1029         /* restore blocking io */
1030         if (!isatty(fileno(stdin)))
1031                 unset_nonblock(fileno(stdin));
1032         if (!isatty(fileno(stdout)))
1033                 unset_nonblock(fileno(stdout));
1034         if (!isatty(fileno(stderr)))
1035                 unset_nonblock(fileno(stderr));
1036
1037         if (received_signal) {
1038                 if (in_non_blocking_mode)       /* XXX */
1039                         leave_non_blocking();
1040                 fatal("Killed by signal %d.", (int) received_signal);
1041         }
1042
1043         /*
1044          * In interactive mode (with pseudo tty) display a message indicating
1045          * that the connection has been closed.
1046          */
1047         if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1048                 snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
1049                 buffer_append(&stderr_buffer, buf, strlen(buf));
1050         }
1051
1052         /* Output any buffered data for stdout. */
1053         while (buffer_len(&stdout_buffer) > 0) {
1054                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1055                     buffer_len(&stdout_buffer));
1056                 if (len <= 0) {
1057                         error("Write failed flushing stdout buffer.");
1058                         break;
1059                 }
1060                 buffer_consume(&stdout_buffer, len);
1061                 stdout_bytes += len;
1062         }
1063
1064         /* Output any buffered data for stderr. */
1065         while (buffer_len(&stderr_buffer) > 0) {
1066                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1067                     buffer_len(&stderr_buffer));
1068                 if (len <= 0) {
1069                         error("Write failed flushing stderr buffer.");
1070                         break;
1071                 }
1072                 buffer_consume(&stderr_buffer, len);
1073                 stderr_bytes += len;
1074         }
1075
1076         /* Clear and free any buffers. */
1077         memset(buf, 0, sizeof(buf));
1078         buffer_free(&stdin_buffer);
1079         buffer_free(&stdout_buffer);
1080         buffer_free(&stderr_buffer);
1081
1082         /* Report bytes transferred, and transfer rates. */
1083         total_time = get_current_time() - start_time;
1084         debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
1085             stdin_bytes, stdout_bytes, stderr_bytes, total_time);
1086         if (total_time > 0)
1087                 debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
1088                     stdin_bytes / total_time, stdout_bytes / total_time,
1089                     stderr_bytes / total_time);
1090
1091         /* Return the exit status of the program. */
1092         debug("Exit status %d", exit_status);
1093         return exit_status;
1094 }
1095
1096 /*********/
1097
1098 static void
1099 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1100 {
1101         u_int data_len;
1102         char *data = packet_get_string(&data_len);
1103         packet_check_eom();
1104         buffer_append(&stdout_buffer, data, data_len);
1105         memset(data, 0, data_len);
1106         xfree(data);
1107 }
1108 static void
1109 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1110 {
1111         u_int data_len;
1112         char *data = packet_get_string(&data_len);
1113         packet_check_eom();
1114         buffer_append(&stderr_buffer, data, data_len);
1115         memset(data, 0, data_len);
1116         xfree(data);
1117 }
1118 static void
1119 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1120 {
1121         exit_status = packet_get_int();
1122         packet_check_eom();
1123         /* Acknowledge the exit. */
1124         packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1125         packet_send();
1126         /*
1127          * Must wait for packet to be sent since we are
1128          * exiting the loop.
1129          */
1130         packet_write_wait();
1131         /* Flag that we want to exit. */
1132         quit_pending = 1;
1133 }
1134
1135 static Channel *
1136 client_request_forwarded_tcpip(const char *request_type, int rchan)
1137 {
1138         Channel *c = NULL;
1139         char *listen_address, *originator_address;
1140         int listen_port, originator_port;
1141         int sock;
1142
1143         /* Get rest of the packet */
1144         listen_address = packet_get_string(NULL);
1145         listen_port = packet_get_int();
1146         originator_address = packet_get_string(NULL);
1147         originator_port = packet_get_int();
1148         packet_check_eom();
1149
1150         debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1151             listen_address, listen_port, originator_address, originator_port);
1152
1153         sock = channel_connect_by_listen_address(listen_port);
1154         if (sock < 0) {
1155                 xfree(originator_address);
1156                 xfree(listen_address);
1157                 return NULL;
1158         }
1159         c = channel_new("forwarded-tcpip",
1160             SSH_CHANNEL_CONNECTING, sock, sock, -1,
1161             CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1162             originator_address, 1);
1163         xfree(originator_address);
1164         xfree(listen_address);
1165         return c;
1166 }
1167
1168 static Channel *
1169 client_request_x11(const char *request_type, int rchan)
1170 {
1171         Channel *c = NULL;
1172         char *originator;
1173         int originator_port;
1174         int sock;
1175
1176         if (!options.forward_x11) {
1177                 error("Warning: ssh server tried X11 forwarding.");
1178                 error("Warning: this is probably a break in attempt by a malicious server.");
1179                 return NULL;
1180         }
1181         originator = packet_get_string(NULL);
1182         if (datafellows & SSH_BUG_X11FWD) {
1183                 debug2("buggy server: x11 request w/o originator_port");
1184                 originator_port = 0;
1185         } else {
1186                 originator_port = packet_get_int();
1187         }
1188         packet_check_eom();
1189         /* XXX check permission */
1190         debug("client_request_x11: request from %s %d", originator,
1191             originator_port);
1192         xfree(originator);
1193         sock = x11_connect_display();
1194         if (sock < 0)
1195                 return NULL;
1196         c = channel_new("x11",
1197             SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1198             CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1199         c->force_drain = 1;
1200         return c;
1201 }
1202
1203 static Channel *
1204 client_request_agent(const char *request_type, int rchan)
1205 {
1206         Channel *c = NULL;
1207         int sock;
1208
1209         if (!options.forward_agent) {
1210                 error("Warning: ssh server tried agent forwarding.");
1211                 error("Warning: this is probably a break in attempt by a malicious server.");
1212                 return NULL;
1213         }
1214         sock =  ssh_get_authentication_socket();
1215         if (sock < 0)
1216                 return NULL;
1217         c = channel_new("authentication agent connection",
1218             SSH_CHANNEL_OPEN, sock, sock, -1,
1219             CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1220             "authentication agent connection", 1);
1221         c->force_drain = 1;
1222         return c;
1223 }
1224
1225 /* XXXX move to generic input handler */
1226 static void
1227 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1228 {
1229         Channel *c = NULL;
1230         char *ctype;
1231         int rchan;
1232         u_int rmaxpack, rwindow, len;
1233
1234         ctype = packet_get_string(&len);
1235         rchan = packet_get_int();
1236         rwindow = packet_get_int();
1237         rmaxpack = packet_get_int();
1238
1239         debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1240             ctype, rchan, rwindow, rmaxpack);
1241
1242         if (strcmp(ctype, "forwarded-tcpip") == 0) {
1243                 c = client_request_forwarded_tcpip(ctype, rchan);
1244         } else if (strcmp(ctype, "x11") == 0) {
1245                 c = client_request_x11(ctype, rchan);
1246         } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1247                 c = client_request_agent(ctype, rchan);
1248         }
1249 /* XXX duplicate : */
1250         if (c != NULL) {
1251                 debug("confirm %s", ctype);
1252                 c->remote_id = rchan;
1253                 c->remote_window = rwindow;
1254                 c->remote_maxpacket = rmaxpack;
1255                 if (c->type != SSH_CHANNEL_CONNECTING) {
1256                         packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1257                         packet_put_int(c->remote_id);
1258                         packet_put_int(c->self);
1259                         packet_put_int(c->local_window);
1260                         packet_put_int(c->local_maxpacket);
1261                         packet_send();
1262                 }
1263         } else {
1264                 debug("failure %s", ctype);
1265                 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1266                 packet_put_int(rchan);
1267                 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1268                 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1269                         packet_put_cstring("open failed");
1270                         packet_put_cstring("");
1271                 }
1272                 packet_send();
1273         }
1274         xfree(ctype);
1275 }
1276 static void
1277 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1278 {
1279         Channel *c = NULL;
1280         int id, reply, success = 0;
1281         char *rtype;
1282
1283         id = packet_get_int();
1284         rtype = packet_get_string(NULL);
1285         reply = packet_get_char();
1286
1287         debug("client_input_channel_req: channel %d rtype %s reply %d",
1288             id, rtype, reply);
1289
1290         if (session_ident == -1) {
1291                 error("client_input_channel_req: no channel %d", session_ident);
1292         } else if (id != session_ident) {
1293                 error("client_input_channel_req: channel %d: wrong channel: %d",
1294                     session_ident, id);
1295         }
1296         c = channel_lookup(id);
1297         if (c == NULL) {
1298                 error("client_input_channel_req: channel %d: unknown channel", id);
1299         } else if (strcmp(rtype, "exit-status") == 0) {
1300                 success = 1;
1301                 exit_status = packet_get_int();
1302                 packet_check_eom();
1303         }
1304         if (reply) {
1305                 packet_start(success ?
1306                     SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1307                 packet_put_int(c->remote_id);
1308                 packet_send();
1309         }
1310         xfree(rtype);
1311 }
1312 static void
1313 client_input_global_request(int type, u_int32_t seq, void *ctxt)
1314 {
1315         char *rtype;
1316         int want_reply;
1317         int success = 0;
1318
1319         rtype = packet_get_string(NULL);
1320         want_reply = packet_get_char();
1321         debug("client_input_global_request: rtype %s want_reply %d", rtype, want_reply);
1322         if (want_reply) {
1323                 packet_start(success ?
1324                     SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1325                 packet_send();
1326                 packet_write_wait();
1327         }
1328         xfree(rtype);
1329 }
1330
1331 static void
1332 client_init_dispatch_20(void)
1333 {
1334         dispatch_init(&dispatch_protocol_error);
1335
1336         dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1337         dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1338         dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1339         dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1340         dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1341         dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1342         dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1343         dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1344         dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1345         dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1346
1347         /* rekeying */
1348         dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1349
1350         /* global request reply messages */
1351         dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
1352         dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1353 }
1354 static void
1355 client_init_dispatch_13(void)
1356 {
1357         dispatch_init(NULL);
1358         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1359         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1360         dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1361         dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1362         dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1363         dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1364         dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
1365         dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
1366         dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1367
1368         dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1369             &auth_input_open_request : &deny_input_open);
1370         dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
1371             &x11_input_open : &deny_input_open);
1372 }
1373 static void
1374 client_init_dispatch_15(void)
1375 {
1376         client_init_dispatch_13();
1377         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1378         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
1379 }
1380 static void
1381 client_init_dispatch(void)
1382 {
1383         if (compat20)
1384                 client_init_dispatch_20();
1385         else if (compat13)
1386                 client_init_dispatch_13();
1387         else
1388                 client_init_dispatch_15();
1389 }