clientloop.c

   1 /* $OpenBSD: clientloop.c,v 1.163 2006/05/16 09:00:00 markus Exp $ */
   2 /*
   3  * Author: Tatu Ylonen <ylo@cs.hut.fi>
   4  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
   5  *                    All rights reserved
   6  * The main loop for the interactive session (client side).
   7  *
   8  * As far as I am concerned, the code I have written for this software
   9  * can be used freely for any purpose.  Any derived versions of this
  10  * software must be clearly marked as such, and if the derived work is
  11  * incompatible with the protocol description in the RFC file, it must be
  12  * called by a name other than "ssh" or "Secure Shell".
  13  *
  14  *
  15  * Copyright (c) 1999 Theo de Raadt.  All rights reserved.
  16  *
  17  * Redistribution and use in source and binary forms, with or without
  18  * modification, are permitted provided that the following conditions
  19  * are met:
  20  * 1. Redistributions of source code must retain the above copyright
  21  *    notice, this list of conditions and the following disclaimer.
  22  * 2. Redistributions in binary form must reproduce the above copyright
  23  *    notice, this list of conditions and the following disclaimer in the
  24  *    documentation and/or other materials provided with the distribution.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  27  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  28  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  29  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  30  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  31  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  35  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  *
  37  *
  38  * SSH2 support added by Markus Friedl.
  39  * Copyright (c) 1999, 2000, 2001 Markus Friedl.  All rights reserved.
  40  *
  41  * Redistribution and use in source and binary forms, with or without
  42  * modification, are permitted provided that the following conditions
  43  * are met:
  44  * 1. Redistributions of source code must retain the above copyright
  45  *    notice, this list of conditions and the following disclaimer.
  46  * 2. Redistributions in binary form must reproduce the above copyright
  47  *    notice, this list of conditions and the following disclaimer in the
  48  *    documentation and/or other materials provided with the distribution.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  51  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  52  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  53  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  54  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  55  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  56  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  57  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  58  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  59  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  60  */
  61
  62 #include "includes.h"
  63
  64 #include <sys/types.h>
  65 #ifdef HAVE_SYS_STAT_H
  66 # include <sys/stat.h>
  67 #endif
  68 #include <sys/ioctl.h>
  69
  70 #include <ctype.h>
  71 #ifdef HAVE_PATHS_H
  72 #include <paths.h>
  73 #endif
  74 #include <signal.h>
  75 #include <termios.h>
  76
  77 #include "ssh.h"
  78 #include "ssh1.h"
  79 #include "ssh2.h"
  80 #include "xmalloc.h"
  81 #include "packet.h"
  82 #include "buffer.h"
  83 #include "compat.h"
  84 #include "channels.h"
  85 #include "dispatch.h"
  86 #include "buffer.h"
  87 #include "bufaux.h"
  88 #include "key.h"
  89 #include "kex.h"
  90 #include "log.h"
  91 #include "readconf.h"
  92 #include "clientloop.h"
  93 #include "sshconnect.h"
  94 #include "authfd.h"
  95 #include "atomicio.h"
  96 #include "sshpty.h"
  97 #include "misc.h"
  98 #include "monitor_fdpass.h"
  99 #include "match.h"
 100 #include "msg.h"
 101
 102 /* import options */
 103 extern Options options;
 104
 105 /* Flag indicating that stdin should be redirected from /dev/null. */
 106 extern int stdin_null_flag;
 107
 108 /* Flag indicating that no shell has been requested */
 109 extern int no_shell_flag;
 110
 111 /* Control socket */
 112 extern int control_fd;
 113
 114 /*
 115  * Name of the host we are connecting to.  This is the name given on the
 116  * command line, or the HostName specified for the user-supplied name in a
 117  * configuration file.
 118  */
 119 extern char *host;
 120
 121 /*
 122  * Flag to indicate that we have received a window change signal which has
 123  * not yet been processed.  This will cause a message indicating the new
 124  * window size to be sent to the server a little later.  This is volatile
 125  * because this is updated in a signal handler.
 126  */
 127 static volatile sig_atomic_t received_window_change_signal = 0;
 128 static volatile sig_atomic_t received_signal = 0;
 129
 130 /* Flag indicating whether the user's terminal is in non-blocking mode. */
 131 static int in_non_blocking_mode = 0;
 132
 133 /* Common data for the client loop code. */
 134 static volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
 135 static int escape_char;         /* Escape character. */
 136 static int escape_pending;      /* Last character was the escape character */
 137 static int last_was_cr;         /* Last character was a newline. */
 138 static int exit_status;         /* Used to store the exit status of the command. */
 139 static int stdin_eof;           /* EOF has been encountered on standard error. */
 140 static Buffer stdin_buffer;     /* Buffer for stdin data. */
 141 static Buffer stdout_buffer;    /* Buffer for stdout data. */
 142 static Buffer stderr_buffer;    /* Buffer for stderr data. */
 143 static u_long stdin_bytes, stdout_bytes, stderr_bytes;
 144 static u_int buffer_high;/* Soft max buffer size. */
 145 static int connection_in;       /* Connection to server (input). */
 146 static int connection_out;      /* Connection to server (output). */
 147 static int need_rekeying;       /* Set to non-zero if rekeying is requested. */
 148 static int session_closed = 0;  /* In SSH2: login session closed. */
 149 static int server_alive_timeouts = 0;
 150
 151 static void client_init_dispatch(void);
 152 int     session_ident = -1;
 153
 154 struct confirm_ctx {
 155         int want_tty;
 156         int want_subsys;
 157         int want_x_fwd;
 158         int want_agent_fwd;
 159         Buffer cmd;
 160         char *term;
 161         struct termios tio;
 162         char **env;
 163 };
 164
 165 /*XXX*/
 166 extern Kex *xxx_kex;
 167
 168 void ssh_process_session2_setup(int, int, int, Buffer *);
 169
 170 /* Restores stdin to blocking mode. */
 171
 172 static void
 173 leave_non_blocking(void)
 174 {
 175         if (in_non_blocking_mode) {
 176                 unset_nonblock(fileno(stdin));
 177                 in_non_blocking_mode = 0;
 178         }
 179 }
 180
 181 /* Puts stdin terminal in non-blocking mode. */
 182
 183 static void
 184 enter_non_blocking(void)
 185 {
 186         in_non_blocking_mode = 1;
 187         set_nonblock(fileno(stdin));
 188 }
 189
 190 /*
 191  * Signal handler for the window change signal (SIGWINCH).  This just sets a
 192  * flag indicating that the window has changed.
 193  */
 194 /*ARGSUSED */
 195 static void
 196 window_change_handler(int sig)
 197 {
 198         received_window_change_signal = 1;
 199         signal(SIGWINCH, window_change_handler);
 200 }
 201
 202 /*
 203  * Signal handler for signals that cause the program to terminate.  These
 204  * signals must be trapped to restore terminal modes.
 205  */
 206 /*ARGSUSED */
 207 static void
 208 signal_handler(int sig)
 209 {
 210         received_signal = sig;
 211         quit_pending = 1;
 212 }
 213
 214 /*
 215  * Returns current time in seconds from Jan 1, 1970 with the maximum
 216  * available resolution.
 217  */
 218
 219 static double
 220 get_current_time(void)
 221 {
 222         struct timeval tv;
 223         gettimeofday(&tv, NULL);
 224         return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
 225 }
 226
 227 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
 228 void
 229 client_x11_get_proto(const char *display, const char *xauth_path,
 230     u_int trusted, char **_proto, char **_data)
 231 {
 232         char cmd[1024];
 233         char line[512];
 234         char xdisplay[512];
 235         static char proto[512], data[512];
 236         FILE *f;
 237         int got_data = 0, generated = 0, do_unlink = 0, i;
 238         char *xauthdir, *xauthfile;
 239         struct stat st;
 240
 241         xauthdir = xauthfile = NULL;
 242         *_proto = proto;
 243         *_data = data;
 244         proto[0] = data[0] = '\0';
 245
 246         if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
 247                 debug("No xauth program.");
 248         } else {
 249                 if (display == NULL) {
 250                         debug("x11_get_proto: DISPLAY not set");
 251                         return;
 252                 }
 253                 /*
 254                  * Handle FamilyLocal case where $DISPLAY does
 255                  * not match an authorization entry.  For this we
 256                  * just try "xauth list unix:displaynum.screennum".
 257                  * XXX: "localhost" match to determine FamilyLocal
 258                  *      is not perfect.
 259                  */
 260                 if (strncmp(display, "localhost:", 10) == 0) {
 261                         snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
 262                             display + 10);
 263                         display = xdisplay;
 264                 }
 265                 if (trusted == 0) {
 266                         xauthdir = xmalloc(MAXPATHLEN);
 267                         xauthfile = xmalloc(MAXPATHLEN);
 268                         strlcpy(xauthdir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
 269                         if (mkdtemp(xauthdir) != NULL) {
 270                                 do_unlink = 1;
 271                                 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
 272                                     xauthdir);
 273                                 snprintf(cmd, sizeof(cmd),
 274                                     "%s -f %s generate %s " SSH_X11_PROTO
 275                                     " untrusted timeout 1200 2>" _PATH_DEVNULL,
 276                                     xauth_path, xauthfile, display);
 277                                 debug2("x11_get_proto: %s", cmd);
 278                                 if (system(cmd) == 0)
 279                                         generated = 1;
 280                         }
 281                 }
 282                 snprintf(cmd, sizeof(cmd),
 283                     "%s %s%s list %s 2>" _PATH_DEVNULL,
 284                     xauth_path,
 285                     generated ? "-f " : "" ,
 286                     generated ? xauthfile : "",
 287                     display);
 288                 debug2("x11_get_proto: %s", cmd);
 289                 f = popen(cmd, "r");
 290                 if (f && fgets(line, sizeof(line), f) &&
 291                     sscanf(line, "%*s %511s %511s", proto, data) == 2)
 292                         got_data = 1;
 293                 if (f)
 294                         pclose(f);
 295         }
 296
 297         if (do_unlink) {
 298                 unlink(xauthfile);
 299                 rmdir(xauthdir);
 300         }
 301         if (xauthdir)
 302                 xfree(xauthdir);
 303         if (xauthfile)
 304                 xfree(xauthfile);
 305
 306         /*
 307          * If we didn't get authentication data, just make up some
 308          * data.  The forwarding code will check the validity of the
 309          * response anyway, and substitute this data.  The X11
 310          * server, however, will ignore this fake data and use
 311          * whatever authentication mechanisms it was using otherwise
 312          * for the local connection.
 313          */
 314         if (!got_data) {
 315                 u_int32_t rnd = 0;
 316
 317                 logit("Warning: No xauth data; "
 318                     "using fake authentication data for X11 forwarding.");
 319                 strlcpy(proto, SSH_X11_PROTO, sizeof proto);
 320                 for (i = 0; i < 16; i++) {
 321                         if (i % 4 == 0)
 322                                 rnd = arc4random();
 323                         snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
 324                             rnd & 0xff);
 325                         rnd >>= 8;
 326                 }
 327         }
 328 }
 329
 330 /*
 331  * This is called when the interactive is entered.  This checks if there is
 332  * an EOF coming on stdin.  We must check this explicitly, as select() does
 333  * not appear to wake up when redirecting from /dev/null.
 334  */
 335
 336 static void
 337 client_check_initial_eof_on_stdin(void)
 338 {
 339         int len;
 340         char buf[1];
 341
 342         /*
 343          * If standard input is to be "redirected from /dev/null", we simply
 344          * mark that we have seen an EOF and send an EOF message to the
 345          * server. Otherwise, we try to read a single character; it appears
 346          * that for some files, such /dev/null, select() never wakes up for
 347          * read for this descriptor, which means that we never get EOF.  This
 348          * way we will get the EOF if stdin comes from /dev/null or similar.
 349          */
 350         if (stdin_null_flag) {
 351                 /* Fake EOF on stdin. */
 352                 debug("Sending eof.");
 353                 stdin_eof = 1;
 354                 packet_start(SSH_CMSG_EOF);
 355                 packet_send();
 356         } else {
 357                 enter_non_blocking();
 358
 359                 /* Check for immediate EOF on stdin. */
 360                 len = read(fileno(stdin), buf, 1);
 361                 if (len == 0) {
 362                         /* EOF.  Record that we have seen it and send EOF to server. */
 363                         debug("Sending eof.");
 364                         stdin_eof = 1;
 365                         packet_start(SSH_CMSG_EOF);
 366                         packet_send();
 367                 } else if (len > 0) {
 368                         /*
 369                          * Got data.  We must store the data in the buffer,
 370                          * and also process it as an escape character if
 371                          * appropriate.
 372                          */
 373                         if ((u_char) buf[0] == escape_char)
 374                                 escape_pending = 1;
 375                         else
 376                                 buffer_append(&stdin_buffer, buf, 1);
 377                 }
 378                 leave_non_blocking();
 379         }
 380 }
 381
 382
 383 /*
 384  * Make packets from buffered stdin data, and buffer them for sending to the
 385  * connection.
 386  */
 387
 388 static void
 389 client_make_packets_from_stdin_data(void)
 390 {
 391         u_int len;
 392
 393         /* Send buffered stdin data to the server. */
 394         while (buffer_len(&stdin_buffer) > 0 &&
 395             packet_not_very_much_data_to_write()) {
 396                 len = buffer_len(&stdin_buffer);
 397                 /* Keep the packets at reasonable size. */
 398                 if (len > packet_get_maxsize())
 399                         len = packet_get_maxsize();
 400                 packet_start(SSH_CMSG_STDIN_DATA);
 401                 packet_put_string(buffer_ptr(&stdin_buffer), len);
 402                 packet_send();
 403                 buffer_consume(&stdin_buffer, len);
 404                 stdin_bytes += len;
 405                 /* If we have a pending EOF, send it now. */
 406                 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
 407                         packet_start(SSH_CMSG_EOF);
 408                         packet_send();
 409                 }
 410         }
 411 }
 412
 413 /*
 414  * Checks if the client window has changed, and sends a packet about it to
 415  * the server if so.  The actual change is detected elsewhere (by a software
 416  * interrupt on Unix); this just checks the flag and sends a message if
 417  * appropriate.
 418  */
 419
 420 static void
 421 client_check_window_change(void)
 422 {
 423         struct winsize ws;
 424
 425         if (! received_window_change_signal)
 426                 return;
 427         /** XXX race */
 428         received_window_change_signal = 0;
 429
 430         debug2("client_check_window_change: changed");
 431
 432         if (compat20) {
 433                 channel_send_window_changes();
 434         } else {
 435                 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
 436                         return;
 437                 packet_start(SSH_CMSG_WINDOW_SIZE);
 438                 packet_put_int((u_int)ws.ws_row);
 439                 packet_put_int((u_int)ws.ws_col);
 440                 packet_put_int((u_int)ws.ws_xpixel);
 441                 packet_put_int((u_int)ws.ws_ypixel);
 442                 packet_send();
 443         }
 444 }
 445
 446 static void
 447 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
 448 {
 449         server_alive_timeouts = 0;
 450         client_global_request_reply_fwd(type, seq, ctxt);
 451 }
 452
 453 static void
 454 server_alive_check(void)
 455 {
 456         if (++server_alive_timeouts > options.server_alive_count_max)
 457                 packet_disconnect("Timeout, server not responding.");
 458         packet_start(SSH2_MSG_GLOBAL_REQUEST);
 459         packet_put_cstring("keepalive@openssh.com");
 460         packet_put_char(1);     /* boolean: want reply */
 461         packet_send();
 462 }
 463
 464 /*
 465  * Waits until the client can do something (some data becomes available on
 466  * one of the file descriptors).
 467  */
 468 static void
 469 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
 470     int *maxfdp, u_int *nallocp, int rekeying)
 471 {
 472         struct timeval tv, *tvp;
 473         int ret;
 474
 475         /* Add any selections by the channel mechanism. */
 476         channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
 477
 478         if (!compat20) {
 479                 /* Read from the connection, unless our buffers are full. */
 480                 if (buffer_len(&stdout_buffer) < buffer_high &&
 481                     buffer_len(&stderr_buffer) < buffer_high &&
 482                     channel_not_very_much_buffered_data())
 483                         FD_SET(connection_in, *readsetp);
 484                 /*
 485                  * Read from stdin, unless we have seen EOF or have very much
 486                  * buffered data to send to the server.
 487                  */
 488                 if (!stdin_eof && packet_not_very_much_data_to_write())
 489                         FD_SET(fileno(stdin), *readsetp);
 490
 491                 /* Select stdout/stderr if have data in buffer. */
 492                 if (buffer_len(&stdout_buffer) > 0)
 493                         FD_SET(fileno(stdout), *writesetp);
 494                 if (buffer_len(&stderr_buffer) > 0)
 495                         FD_SET(fileno(stderr), *writesetp);
 496         } else {
 497                 /* channel_prepare_select could have closed the last channel */
 498                 if (session_closed && !channel_still_open() &&
 499                     !packet_have_data_to_write()) {
 500                         /* clear mask since we did not call select() */
 501                         memset(*readsetp, 0, *nallocp);
 502                         memset(*writesetp, 0, *nallocp);
 503                         return;
 504                 } else {
 505                         FD_SET(connection_in, *readsetp);
 506                 }
 507         }
 508
 509         /* Select server connection if have data to write to the server. */
 510         if (packet_have_data_to_write())
 511                 FD_SET(connection_out, *writesetp);
 512
 513         if (control_fd != -1)
 514                 FD_SET(control_fd, *readsetp);
 515
 516         /*
 517          * Wait for something to happen.  This will suspend the process until
 518          * some selected descriptor can be read, written, or has some other
 519          * event pending.
 520          */
 521
 522         if (options.server_alive_interval == 0 || !compat20)
 523                 tvp = NULL;
 524         else {
 525                 tv.tv_sec = options.server_alive_interval;
 526                 tv.tv_usec = 0;
 527                 tvp = &tv;
 528         }
 529         ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
 530         if (ret < 0) {
 531                 char buf[100];
 532
 533                 /*
 534                  * We have to clear the select masks, because we return.
 535                  * We have to return, because the mainloop checks for the flags
 536                  * set by the signal handlers.
 537                  */
 538                 memset(*readsetp, 0, *nallocp);
 539                 memset(*writesetp, 0, *nallocp);
 540
 541                 if (errno == EINTR)
 542                         return;
 543                 /* Note: we might still have data in the buffers. */
 544                 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
 545                 buffer_append(&stderr_buffer, buf, strlen(buf));
 546                 quit_pending = 1;
 547         } else if (ret == 0)
 548                 server_alive_check();
 549 }
 550
 551 static void
 552 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
 553 {
 554         /* Flush stdout and stderr buffers. */
 555         if (buffer_len(bout) > 0)
 556                 atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
 557         if (buffer_len(berr) > 0)
 558                 atomicio(vwrite, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
 559
 560         leave_raw_mode();
 561
 562         /*
 563          * Free (and clear) the buffer to reduce the amount of data that gets
 564          * written to swap.
 565          */
 566         buffer_free(bin);
 567         buffer_free(bout);
 568         buffer_free(berr);
 569
 570         /* Send the suspend signal to the program itself. */
 571         kill(getpid(), SIGTSTP);
 572
 573         /* Reset window sizes in case they have changed */
 574         received_window_change_signal = 1;
 575
 576         /* OK, we have been continued by the user. Reinitialize buffers. */
 577         buffer_init(bin);
 578         buffer_init(bout);
 579         buffer_init(berr);
 580
 581         enter_raw_mode();
 582 }
 583
 584 static void
 585 client_process_net_input(fd_set *readset)
 586 {
 587         int len;
 588         char buf[8192];
 589
 590         /*
 591          * Read input from the server, and add any such data to the buffer of
 592          * the packet subsystem.
 593          */
 594         if (FD_ISSET(connection_in, readset)) {
 595                 /* Read as much as possible. */
 596                 len = read(connection_in, buf, sizeof(buf));
 597                 if (len == 0) {
 598                         /* Received EOF.  The remote host has closed the connection. */
 599                         snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
 600                                  host);
 601                         buffer_append(&stderr_buffer, buf, strlen(buf));
 602                         quit_pending = 1;
 603                         return;
 604                 }
 605                 /*
 606                  * There is a kernel bug on Solaris that causes select to
 607                  * sometimes wake up even though there is no data available.
 608                  */
 609                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
 610                         len = 0;
 611
 612                 if (len < 0) {
 613                         /* An error has encountered.  Perhaps there is a network problem. */
 614                         snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
 615                                  host, strerror(errno));
 616                         buffer_append(&stderr_buffer, buf, strlen(buf));
 617                         quit_pending = 1;
 618                         return;
 619                 }
 620                 packet_process_incoming(buf, len);
 621         }
 622 }
 623
 624 static void
 625 client_subsystem_reply(int type, u_int32_t seq, void *ctxt)
 626 {
 627         int id;
 628         Channel *c;
 629
 630         id = packet_get_int();
 631         packet_check_eom();
 632
 633         if ((c = channel_lookup(id)) == NULL) {
 634                 error("%s: no channel for id %d", __func__, id);
 635                 return;
 636         }
 637
 638         if (type == SSH2_MSG_CHANNEL_SUCCESS)
 639                 debug2("Request suceeded on channel %d", id);
 640         else if (type == SSH2_MSG_CHANNEL_FAILURE) {
 641                 error("Request failed on channel %d", id);
 642                 channel_free(c);
 643         }
 644 }
 645
 646 static void
 647 client_extra_session2_setup(int id, void *arg)
 648 {
 649         struct confirm_ctx *cctx = arg;
 650         const char *display;
 651         Channel *c;
 652         int i;
 653
 654         if (cctx == NULL)
 655                 fatal("%s: cctx == NULL", __func__);
 656         if ((c = channel_lookup(id)) == NULL)
 657                 fatal("%s: no channel for id %d", __func__, id);
 658
 659         display = getenv("DISPLAY");
 660         if (cctx->want_x_fwd && options.forward_x11 && display != NULL) {
 661                 char *proto, *data;
 662                 /* Get reasonable local authentication information. */
 663                 client_x11_get_proto(display, options.xauth_location,
 664                     options.forward_x11_trusted, &proto, &data);
 665                 /* Request forwarding with authentication spoofing. */
 666                 debug("Requesting X11 forwarding with authentication spoofing.");
 667                 x11_request_forwarding_with_spoofing(id, display, proto, data);
 668                 /* XXX wait for reply */
 669         }
 670
 671         if (cctx->want_agent_fwd && options.forward_agent) {
 672                 debug("Requesting authentication agent forwarding.");
 673                 channel_request_start(id, "auth-agent-req@openssh.com", 0);
 674                 packet_send();
 675         }
 676
 677         client_session2_setup(id, cctx->want_tty, cctx->want_subsys,
 678             cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env,
 679             client_subsystem_reply);
 680
 681         c->confirm_ctx = NULL;
 682         buffer_free(&cctx->cmd);
 683         xfree(cctx->term);
 684         if (cctx->env != NULL) {
 685                 for (i = 0; cctx->env[i] != NULL; i++)
 686                         xfree(cctx->env[i]);
 687                 xfree(cctx->env);
 688         }
 689         xfree(cctx);
 690 }
 691
 692 static void
 693 client_process_control(fd_set *readset)
 694 {
 695         Buffer m;
 696         Channel *c;
 697         int client_fd, new_fd[3], ver, allowed;
 698         socklen_t addrlen;
 699         struct sockaddr_storage addr;
 700         struct confirm_ctx *cctx;
 701         char *cmd;
 702         u_int i, len, env_len, command, flags;
 703         uid_t euid;
 704         gid_t egid;
 705
 706         /*
 707          * Accept connection on control socket
 708          */
 709         if (control_fd == -1 || !FD_ISSET(control_fd, readset))
 710                 return;
 711
 712         memset(&addr, 0, sizeof(addr));
 713         addrlen = sizeof(addr);
 714         if ((client_fd = accept(control_fd,
 715             (struct sockaddr*)&addr, &addrlen)) == -1) {
 716                 error("%s accept: %s", __func__, strerror(errno));
 717                 return;
 718         }
 719
 720         if (getpeereid(client_fd, &euid, &egid) < 0) {
 721                 error("%s getpeereid failed: %s", __func__, strerror(errno));
 722                 close(client_fd);
 723                 return;
 724         }
 725         if ((euid != 0) && (getuid() != euid)) {
 726                 error("control mode uid mismatch: peer euid %u != uid %u",
 727                     (u_int) euid, (u_int) getuid());
 728                 close(client_fd);
 729                 return;
 730         }
 731
 732         unset_nonblock(client_fd);
 733
 734         /* Read command */
 735         buffer_init(&m);
 736         if (ssh_msg_recv(client_fd, &m) == -1) {
 737                 error("%s: client msg_recv failed", __func__);
 738                 close(client_fd);
 739                 buffer_free(&m);
 740                 return;
 741         }
 742         if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
 743                 error("%s: wrong client version %d", __func__, ver);
 744                 buffer_free(&m);
 745                 close(client_fd);
 746                 return;
 747         }
 748
 749         allowed = 1;
 750         command = buffer_get_int(&m);
 751         flags = buffer_get_int(&m);
 752
 753         buffer_clear(&m);
 754
 755         switch (command) {
 756         case SSHMUX_COMMAND_OPEN:
 757                 if (options.control_master == SSHCTL_MASTER_ASK ||
 758                     options.control_master == SSHCTL_MASTER_AUTO_ASK)
 759                         allowed = ask_permission("Allow shared connection "
 760                             "to %s? ", host);
 761                 /* continue below */
 762                 break;
 763         case SSHMUX_COMMAND_TERMINATE:
 764                 if (options.control_master == SSHCTL_MASTER_ASK ||
 765                     options.control_master == SSHCTL_MASTER_AUTO_ASK)
 766                         allowed = ask_permission("Terminate shared connection "
 767                             "to %s? ", host);
 768                 if (allowed)
 769                         quit_pending = 1;
 770                 /* FALLTHROUGH */
 771         case SSHMUX_COMMAND_ALIVE_CHECK:
 772                 /* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */
 773                 buffer_clear(&m);
 774                 buffer_put_int(&m, allowed);
 775                 buffer_put_int(&m, getpid());
 776                 if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 777                         error("%s: client msg_send failed", __func__);
 778                         close(client_fd);
 779                         buffer_free(&m);
 780                         return;
 781                 }
 782                 buffer_free(&m);
 783                 close(client_fd);
 784                 return;
 785         default:
 786                 error("Unsupported command %d", command);
 787                 buffer_free(&m);
 788                 close(client_fd);
 789                 return;
 790         }
 791
 792         /* Reply for SSHMUX_COMMAND_OPEN */
 793         buffer_clear(&m);
 794         buffer_put_int(&m, allowed);
 795         buffer_put_int(&m, getpid());
 796         if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 797                 error("%s: client msg_send failed", __func__);
 798                 close(client_fd);
 799                 buffer_free(&m);
 800                 return;
 801         }
 802
 803         if (!allowed) {
 804                 error("Refused control connection");
 805                 close(client_fd);
 806                 buffer_free(&m);
 807                 return;
 808         }
 809
 810         buffer_clear(&m);
 811         if (ssh_msg_recv(client_fd, &m) == -1) {
 812                 error("%s: client msg_recv failed", __func__);
 813                 close(client_fd);
 814                 buffer_free(&m);
 815                 return;
 816         }
 817         if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
 818                 error("%s: wrong client version %d", __func__, ver);
 819                 buffer_free(&m);
 820                 close(client_fd);
 821                 return;
 822         }
 823
 824         cctx = xcalloc(1, sizeof(*cctx));
 825         cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0;
 826         cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0;
 827         cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0;
 828         cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0;
 829         cctx->term = buffer_get_string(&m, &len);
 830
 831         cmd = buffer_get_string(&m, &len);
 832         buffer_init(&cctx->cmd);
 833         buffer_append(&cctx->cmd, cmd, strlen(cmd));
 834
 835         env_len = buffer_get_int(&m);
 836         env_len = MIN(env_len, 4096);
 837         debug3("%s: receiving %d env vars", __func__, env_len);
 838         if (env_len != 0) {
 839                 cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env));
 840                 for (i = 0; i < env_len; i++)
 841                         cctx->env[i] = buffer_get_string(&m, &len);
 842                 cctx->env[i] = NULL;
 843         }
 844
 845         debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__,
 846             cctx->want_tty, cctx->want_subsys, cmd);
 847         xfree(cmd);
 848
 849         /* Gather fds from client */
 850         new_fd[0] = mm_receive_fd(client_fd);
 851         new_fd[1] = mm_receive_fd(client_fd);
 852         new_fd[2] = mm_receive_fd(client_fd);
 853
 854         debug2("%s: got fds stdin %d, stdout %d, stderr %d", __func__,
 855             new_fd[0], new_fd[1], new_fd[2]);
 856
 857         /* Try to pick up ttymodes from client before it goes raw */
 858         if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1)
 859                 error("%s: tcgetattr: %s", __func__, strerror(errno));
 860
 861         /* This roundtrip is just for synchronisation of ttymodes */
 862         buffer_clear(&m);
 863         if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 864                 error("%s: client msg_send failed", __func__);
 865                 close(client_fd);
 866                 close(new_fd[0]);
 867                 close(new_fd[1]);
 868                 close(new_fd[2]);
 869                 buffer_free(&m);
 870                 xfree(cctx->term);
 871                 if (env_len != 0) {
 872                         for (i = 0; i < env_len; i++)
 873                                 xfree(cctx->env[i]);
 874                         xfree(cctx->env);
 875                 }
 876                 return;
 877         }
 878         buffer_free(&m);
 879
 880         /* enable nonblocking unless tty */
 881         if (!isatty(new_fd[0]))
 882                 set_nonblock(new_fd[0]);
 883         if (!isatty(new_fd[1]))
 884                 set_nonblock(new_fd[1]);
 885         if (!isatty(new_fd[2]))
 886                 set_nonblock(new_fd[2]);
 887
 888         set_nonblock(client_fd);
 889
 890         c = channel_new("session", SSH_CHANNEL_OPENING,
 891             new_fd[0], new_fd[1], new_fd[2],
 892             CHAN_SES_WINDOW_DEFAULT, CHAN_SES_PACKET_DEFAULT,
 893             CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0);
 894
 895         /* XXX */
 896         c->ctl_fd = client_fd;
 897
 898         debug3("%s: channel_new: %d", __func__, c->self);
 899
 900         channel_send_open(c->self);
 901         channel_register_confirm(c->self, client_extra_session2_setup, cctx);
 902 }
 903
 904 static void
 905 process_cmdline(void)
 906 {
 907         void (*handler)(int);
 908         char *s, *cmd, *cancel_host;
 909         int delete = 0;
 910         int local = 0;
 911         u_short cancel_port;
 912         Forward fwd;
 913
 914         leave_raw_mode();
 915         handler = signal(SIGINT, SIG_IGN);
 916         cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
 917         if (s == NULL)
 918                 goto out;
 919         while (*s && isspace(*s))
 920                 s++;
 921         if (*s == '-')
 922                 s++;    /* Skip cmdline '-', if any */
 923         if (*s == '\0')
 924                 goto out;
 925
 926         if (*s == 'h' || *s == 'H' || *s == '?') {
 927                 logit("Commands:");
 928                 logit("      -Lport:host:hostport    Request local forward");
 929                 logit("      -Rport:host:hostport    Request remote forward");
 930                 logit("      -KRhostport             Cancel remote forward");
 931                 if (!options.permit_local_command)
 932                         goto out;
 933                 logit("      !args                   Execute local command");
 934                 goto out;
 935         }
 936
 937         if (*s == '!' && options.permit_local_command) {
 938                 s++;
 939                 ssh_local_cmd(s);
 940                 goto out;
 941         }
 942
 943         if (*s == 'K') {
 944                 delete = 1;
 945                 s++;
 946         }
 947         if (*s != 'L' && *s != 'R') {
 948                 logit("Invalid command.");
 949                 goto out;
 950         }
 951         if (*s == 'L')
 952                 local = 1;
 953         if (local && delete) {
 954                 logit("Not supported.");
 955                 goto out;
 956         }
 957         if ((!local || delete) && !compat20) {
 958                 logit("Not supported for SSH protocol version 1.");
 959                 goto out;
 960         }
 961
 962         s++;
 963         while (*s && isspace(*s))
 964                 s++;
 965
 966         if (delete) {
 967                 cancel_port = 0;
 968                 cancel_host = hpdelim(&s);      /* may be NULL */
 969                 if (s != NULL) {
 970                         cancel_port = a2port(s);
 971                         cancel_host = cleanhostname(cancel_host);
 972                 } else {
 973                         cancel_port = a2port(cancel_host);
 974                         cancel_host = NULL;
 975                 }
 976                 if (cancel_port == 0) {
 977                         logit("Bad forwarding close port");
 978                         goto out;
 979                 }
 980                 channel_request_rforward_cancel(cancel_host, cancel_port);
 981         } else {
 982                 if (!parse_forward(&fwd, s)) {
 983                         logit("Bad forwarding specification.");
 984                         goto out;
 985                 }
 986                 if (local) {
 987                         if (channel_setup_local_fwd_listener(fwd.listen_host,
 988                             fwd.listen_port, fwd.connect_host,
 989                             fwd.connect_port, options.gateway_ports) < 0) {
 990                                 logit("Port forwarding failed.");
 991                                 goto out;
 992                         }
 993                 } else {
 994                         channel_request_remote_forwarding(fwd.listen_host,
 995                             fwd.listen_port, fwd.connect_host,
 996                             fwd.connect_port);
 997                 }
 998
 999                 logit("Forwarding port.");
1000         }
1001
1002 out:
1003         signal(SIGINT, handler);
1004         enter_raw_mode();
1005         if (cmd)
1006                 xfree(cmd);
1007 }
1008
1009 /* process the characters one by one */
1010 static int
1011 process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
1012 {
1013         char string[1024];
1014         pid_t pid;
1015         int bytes = 0;
1016         u_int i;
1017         u_char ch;
1018         char *s;
1019
1020         if (len <= 0)
1021                 return (0);
1022
1023         for (i = 0; i < (u_int)len; i++) {
1024                 /* Get one character at a time. */
1025                 ch = buf[i];
1026
1027                 if (escape_pending) {
1028                         /* We have previously seen an escape character. */
1029                         /* Clear the flag now. */
1030                         escape_pending = 0;
1031
1032                         /* Process the escaped character. */
1033                         switch (ch) {
1034                         case '.':
1035                                 /* Terminate the connection. */
1036                                 snprintf(string, sizeof string, "%c.\r\n", escape_char);
1037                                 buffer_append(berr, string, strlen(string));
1038
1039                                 quit_pending = 1;
1040                                 return -1;
1041
1042                         case 'Z' - 64:
1043                                 /* Suspend the program. */
1044                                 /* Print a message to that effect to the user. */
1045                                 snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
1046                                 buffer_append(berr, string, strlen(string));
1047
1048                                 /* Restore terminal modes and suspend. */
1049                                 client_suspend_self(bin, bout, berr);
1050
1051                                 /* We have been continued. */
1052                                 continue;
1053
1054                         case 'B':
1055                                 if (compat20) {
1056                                         snprintf(string, sizeof string,
1057                                             "%cB\r\n", escape_char);
1058                                         buffer_append(berr, string,
1059                                             strlen(string));
1060                                         channel_request_start(session_ident,
1061                                             "break", 0);
1062                                         packet_put_int(1000);
1063                                         packet_send();
1064                                 }
1065                                 continue;
1066
1067                         case 'R':
1068                                 if (compat20) {
1069                                         if (datafellows & SSH_BUG_NOREKEY)
1070                                                 logit("Server does not support re-keying");
1071                                         else
1072                                                 need_rekeying = 1;
1073                                 }
1074                                 continue;
1075
1076                         case '&':
1077                                 /*
1078                                  * Detach the program (continue to serve connections,
1079                                  * but put in background and no more new connections).
1080                                  */
1081                                 /* Restore tty modes. */
1082                                 leave_raw_mode();
1083
1084                                 /* Stop listening for new connections. */
1085                                 channel_stop_listening();
1086
1087                                 snprintf(string, sizeof string,
1088                                     "%c& [backgrounded]\n", escape_char);
1089                                 buffer_append(berr, string, strlen(string));
1090
1091                                 /* Fork into background. */
1092                                 pid = fork();
1093                                 if (pid < 0) {
1094                                         error("fork: %.100s", strerror(errno));
1095                                         continue;
1096                                 }
1097                                 if (pid != 0) { /* This is the parent. */
1098                                         /* The parent just exits. */
1099                                         exit(0);
1100                                 }
1101                                 /* The child continues serving connections. */
1102                                 if (compat20) {
1103                                         buffer_append(bin, "\004", 1);
1104                                         /* fake EOF on stdin */
1105                                         return -1;
1106                                 } else if (!stdin_eof) {
1107                                         /*
1108                                          * Sending SSH_CMSG_EOF alone does not always appear
1109                                          * to be enough.  So we try to send an EOF character
1110                                          * first.
1111                                          */
1112                                         packet_start(SSH_CMSG_STDIN_DATA);
1113                                         packet_put_string("\004", 1);
1114                                         packet_send();
1115                                         /* Close stdin. */
1116                                         stdin_eof = 1;
1117                                         if (buffer_len(bin) == 0) {
1118                                                 packet_start(SSH_CMSG_EOF);
1119                                                 packet_send();
1120                                         }
1121                                 }
1122                                 continue;
1123
1124                         case '?':
1125                                 snprintf(string, sizeof string,
1126 "%c?\r\n\
1127 Supported escape sequences:\r\n\
1128 %c.  - terminate connection\r\n\
1129 %cB  - send a BREAK to the remote system\r\n\
1130 %cC  - open a command line\r\n\
1131 %cR  - Request rekey (SSH protocol 2 only)\r\n\
1132 %c^Z - suspend ssh\r\n\
1133 %c#  - list forwarded connections\r\n\
1134 %c&  - background ssh (when waiting for connections to terminate)\r\n\
1135 %c?  - this message\r\n\
1136 %c%c  - send the escape character by typing it twice\r\n\
1137 (Note that escapes are only recognized immediately after newline.)\r\n",
1138                                     escape_char, escape_char, escape_char, escape_char,
1139                                     escape_char, escape_char, escape_char, escape_char,
1140                                     escape_char, escape_char, escape_char);
1141                                 buffer_append(berr, string, strlen(string));
1142                                 continue;
1143
1144                         case '#':
1145                                 snprintf(string, sizeof string, "%c#\r\n", escape_char);
1146                                 buffer_append(berr, string, strlen(string));
1147                                 s = channel_open_message();
1148                                 buffer_append(berr, s, strlen(s));
1149                                 xfree(s);
1150                                 continue;
1151
1152                         case 'C':
1153                                 process_cmdline();
1154                                 continue;
1155
1156                         default:
1157                                 if (ch != escape_char) {
1158                                         buffer_put_char(bin, escape_char);
1159                                         bytes++;
1160                                 }
1161                                 /* Escaped characters fall through here */
1162                                 break;
1163                         }
1164                 } else {
1165                         /*
1166                          * The previous character was not an escape char. Check if this
1167                          * is an escape.
1168                          */
1169                         if (last_was_cr && ch == escape_char) {
1170                                 /* It is. Set the flag and continue to next character. */
1171                                 escape_pending = 1;
1172                                 continue;
1173                         }
1174                 }
1175
1176                 /*
1177                  * Normal character.  Record whether it was a newline,
1178                  * and append it to the buffer.
1179                  */
1180                 last_was_cr = (ch == '\r' || ch == '\n');
1181                 buffer_put_char(bin, ch);
1182                 bytes++;
1183         }
1184         return bytes;
1185 }
1186
1187 static void
1188 client_process_input(fd_set *readset)
1189 {
1190         int len;
1191         char buf[8192];
1192
1193         /* Read input from stdin. */
1194         if (FD_ISSET(fileno(stdin), readset)) {
1195                 /* Read as much as possible. */
1196                 len = read(fileno(stdin), buf, sizeof(buf));
1197                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
1198                         return;         /* we'll try again later */
1199                 if (len <= 0) {
1200                         /*
1201                          * Received EOF or error.  They are treated
1202                          * similarly, except that an error message is printed
1203                          * if it was an error condition.
1204                          */
1205                         if (len < 0) {
1206                                 snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
1207                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1208                         }
1209                         /* Mark that we have seen EOF. */
1210                         stdin_eof = 1;
1211                         /*
1212                          * Send an EOF message to the server unless there is
1213                          * data in the buffer.  If there is data in the
1214                          * buffer, no message will be sent now.  Code
1215                          * elsewhere will send the EOF when the buffer
1216                          * becomes empty if stdin_eof is set.
1217                          */
1218                         if (buffer_len(&stdin_buffer) == 0) {
1219                                 packet_start(SSH_CMSG_EOF);
1220                                 packet_send();
1221                         }
1222                 } else if (escape_char == SSH_ESCAPECHAR_NONE) {
1223                         /*
1224                          * Normal successful read, and no escape character.
1225                          * Just append the data to buffer.
1226                          */
1227                         buffer_append(&stdin_buffer, buf, len);
1228                 } else {
1229                         /*
1230                          * Normal, successful read.  But we have an escape character
1231                          * and have to process the characters one by one.
1232                          */
1233                         if (process_escapes(&stdin_buffer, &stdout_buffer,
1234                             &stderr_buffer, buf, len) == -1)
1235                                 return;
1236                 }
1237         }
1238 }
1239
1240 static void
1241 client_process_output(fd_set *writeset)
1242 {
1243         int len;
1244         char buf[100];
1245
1246         /* Write buffered output to stdout. */
1247         if (FD_ISSET(fileno(stdout), writeset)) {
1248                 /* Write as much data as possible. */
1249                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1250                     buffer_len(&stdout_buffer));
1251                 if (len <= 0) {
1252                         if (errno == EINTR || errno == EAGAIN)
1253                                 len = 0;
1254                         else {
1255                                 /*
1256                                  * An error or EOF was encountered.  Put an
1257                                  * error message to stderr buffer.
1258                                  */
1259                                 snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
1260                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1261                                 quit_pending = 1;
1262                                 return;
1263                         }
1264                 }
1265                 /* Consume printed data from the buffer. */
1266                 buffer_consume(&stdout_buffer, len);
1267                 stdout_bytes += len;
1268         }
1269         /* Write buffered output to stderr. */
1270         if (FD_ISSET(fileno(stderr), writeset)) {
1271                 /* Write as much data as possible. */
1272                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1273                     buffer_len(&stderr_buffer));
1274                 if (len <= 0) {
1275                         if (errno == EINTR || errno == EAGAIN)
1276                                 len = 0;
1277                         else {
1278                                 /* EOF or error, but can't even print error message. */
1279                                 quit_pending = 1;
1280                                 return;
1281                         }
1282                 }
1283                 /* Consume printed characters from the buffer. */
1284                 buffer_consume(&stderr_buffer, len);
1285                 stderr_bytes += len;
1286         }
1287 }
1288
1289 /*
1290  * Get packets from the connection input buffer, and process them as long as
1291  * there are packets available.
1292  *
1293  * Any unknown packets received during the actual
1294  * session cause the session to terminate.  This is
1295  * intended to make debugging easier since no
1296  * confirmations are sent.  Any compatible protocol
1297  * extensions must be negotiated during the
1298  * preparatory phase.
1299  */
1300
1301 static void
1302 client_process_buffered_input_packets(void)
1303 {
1304         dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL);
1305 }
1306
1307 /* scan buf[] for '~' before sending data to the peer */
1308
1309 static int
1310 simple_escape_filter(Channel *c, char *buf, int len)
1311 {
1312         /* XXX we assume c->extended is writeable */
1313         return process_escapes(&c->input, &c->output, &c->extended, buf, len);
1314 }
1315
1316 static void
1317 client_channel_closed(int id, void *arg)
1318 {
1319         channel_cancel_cleanup(id);
1320         session_closed = 1;
1321         leave_raw_mode();
1322 }
1323
1324 /*
1325  * Implements the interactive session with the server.  This is called after
1326  * the user has been authenticated, and a command has been started on the
1327  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1328  * used as an escape character for terminating or suspending the session.
1329  */
1330
1331 int
1332 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1333 {
1334         fd_set *readset = NULL, *writeset = NULL;
1335         double start_time, total_time;
1336         int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1337         u_int nalloc = 0;
1338         char buf[100];
1339
1340         debug("Entering interactive session.");
1341
1342         start_time = get_current_time();
1343
1344         /* Initialize variables. */
1345         escape_pending = 0;
1346         last_was_cr = 1;
1347         exit_status = -1;
1348         stdin_eof = 0;
1349         buffer_high = 64 * 1024;
1350         connection_in = packet_get_connection_in();
1351         connection_out = packet_get_connection_out();
1352         max_fd = MAX(connection_in, connection_out);
1353         if (control_fd != -1)
1354                 max_fd = MAX(max_fd, control_fd);
1355
1356         if (!compat20) {
1357                 /* enable nonblocking unless tty */
1358                 if (!isatty(fileno(stdin)))
1359                         set_nonblock(fileno(stdin));
1360                 if (!isatty(fileno(stdout)))
1361                         set_nonblock(fileno(stdout));
1362                 if (!isatty(fileno(stderr)))
1363                         set_nonblock(fileno(stderr));
1364                 max_fd = MAX(max_fd, fileno(stdin));
1365                 max_fd = MAX(max_fd, fileno(stdout));
1366                 max_fd = MAX(max_fd, fileno(stderr));
1367         }
1368         stdin_bytes = 0;
1369         stdout_bytes = 0;
1370         stderr_bytes = 0;
1371         quit_pending = 0;
1372         escape_char = escape_char_arg;
1373
1374         /* Initialize buffers. */
1375         buffer_init(&stdin_buffer);
1376         buffer_init(&stdout_buffer);
1377         buffer_init(&stderr_buffer);
1378
1379         client_init_dispatch();
1380
1381         /*
1382          * Set signal handlers, (e.g. to restore non-blocking mode)
1383          * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1384          */
1385         if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1386                 signal(SIGHUP, signal_handler);
1387         if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1388                 signal(SIGINT, signal_handler);
1389         if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1390                 signal(SIGQUIT, signal_handler);
1391         if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1392                 signal(SIGTERM, signal_handler);
1393         signal(SIGWINCH, window_change_handler);
1394
1395         if (have_pty)
1396                 enter_raw_mode();
1397
1398         if (compat20) {
1399                 session_ident = ssh2_chan_id;
1400                 if (escape_char != SSH_ESCAPECHAR_NONE)
1401                         channel_register_filter(session_ident,
1402                             simple_escape_filter, NULL);
1403                 if (session_ident != -1)
1404                         channel_register_cleanup(session_ident,
1405                             client_channel_closed, 0);
1406         } else {
1407                 /* Check if we should immediately send eof on stdin. */
1408                 client_check_initial_eof_on_stdin();
1409         }
1410
1411         /* Main loop of the client for the interactive session mode. */
1412         while (!quit_pending) {
1413
1414                 /* Process buffered packets sent by the server. */
1415                 client_process_buffered_input_packets();
1416
1417                 if (compat20 && session_closed && !channel_still_open())
1418                         break;
1419
1420                 rekeying = (xxx_kex != NULL && !xxx_kex->done);
1421
1422                 if (rekeying) {
1423                         debug("rekeying in progress");
1424                 } else {
1425                         /*
1426                          * Make packets of buffered stdin data, and buffer
1427                          * them for sending to the server.
1428                          */
1429                         if (!compat20)
1430                                 client_make_packets_from_stdin_data();
1431
1432                         /*
1433                          * Make packets from buffered channel data, and
1434                          * enqueue them for sending to the server.
1435                          */
1436                         if (packet_not_very_much_data_to_write())
1437                                 channel_output_poll();
1438
1439                         /*
1440                          * Check if the window size has changed, and buffer a
1441                          * message about it to the server if so.
1442                          */
1443                         client_check_window_change();
1444
1445                         if (quit_pending)
1446                                 break;
1447                 }
1448                 /*
1449                  * Wait until we have something to do (something becomes
1450                  * available on one of the descriptors).
1451                  */
1452                 max_fd2 = max_fd;
1453                 client_wait_until_can_do_something(&readset, &writeset,
1454                     &max_fd2, &nalloc, rekeying);
1455
1456                 if (quit_pending)
1457                         break;
1458
1459                 /* Do channel operations unless rekeying in progress. */
1460                 if (!rekeying) {
1461                         channel_after_select(readset, writeset);
1462                         if (need_rekeying || packet_need_rekeying()) {
1463                                 debug("need rekeying");
1464                                 xxx_kex->done = 0;
1465                                 kex_send_kexinit(xxx_kex);
1466                                 need_rekeying = 0;
1467                         }
1468                 }
1469
1470                 /* Buffer input from the connection.  */
1471                 client_process_net_input(readset);
1472
1473                 /* Accept control connections.  */
1474                 client_process_control(readset);
1475
1476                 if (quit_pending)
1477                         break;
1478
1479                 if (!compat20) {
1480                         /* Buffer data from stdin */
1481                         client_process_input(readset);
1482                         /*
1483                          * Process output to stdout and stderr.  Output to
1484                          * the connection is processed elsewhere (above).
1485                          */
1486                         client_process_output(writeset);
1487                 }
1488
1489                 /* Send as much buffered packet data as possible to the sender. */
1490                 if (FD_ISSET(connection_out, writeset))
1491                         packet_write_poll();
1492         }
1493         if (readset)
1494                 xfree(readset);
1495         if (writeset)
1496                 xfree(writeset);
1497
1498         /* Terminate the session. */
1499
1500         /* Stop watching for window change. */
1501         signal(SIGWINCH, SIG_DFL);
1502
1503         channel_free_all();
1504
1505         if (have_pty)
1506                 leave_raw_mode();
1507
1508         /* restore blocking io */
1509         if (!isatty(fileno(stdin)))
1510                 unset_nonblock(fileno(stdin));
1511         if (!isatty(fileno(stdout)))
1512                 unset_nonblock(fileno(stdout));
1513         if (!isatty(fileno(stderr)))
1514                 unset_nonblock(fileno(stderr));
1515
1516         /*
1517          * If there was no shell or command requested, there will be no remote
1518          * exit status to be returned.  In that case, clear error code if the
1519          * connection was deliberately terminated at this end.
1520          */
1521         if (no_shell_flag && received_signal == SIGTERM) {
1522                 received_signal = 0;
1523                 exit_status = 0;
1524         }
1525
1526         if (received_signal)
1527                 fatal("Killed by signal %d.", (int) received_signal);
1528
1529         /*
1530          * In interactive mode (with pseudo tty) display a message indicating
1531          * that the connection has been closed.
1532          */
1533         if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1534                 snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
1535                 buffer_append(&stderr_buffer, buf, strlen(buf));
1536         }
1537
1538         /* Output any buffered data for stdout. */
1539         while (buffer_len(&stdout_buffer) > 0) {
1540                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1541                     buffer_len(&stdout_buffer));
1542                 if (len <= 0) {
1543                         error("Write failed flushing stdout buffer.");
1544                         break;
1545                 }
1546                 buffer_consume(&stdout_buffer, len);
1547                 stdout_bytes += len;
1548         }
1549
1550         /* Output any buffered data for stderr. */
1551         while (buffer_len(&stderr_buffer) > 0) {
1552                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1553                     buffer_len(&stderr_buffer));
1554                 if (len <= 0) {
1555                         error("Write failed flushing stderr buffer.");
1556                         break;
1557                 }
1558                 buffer_consume(&stderr_buffer, len);
1559                 stderr_bytes += len;
1560         }
1561
1562         /* Clear and free any buffers. */
1563         memset(buf, 0, sizeof(buf));
1564         buffer_free(&stdin_buffer);
1565         buffer_free(&stdout_buffer);
1566         buffer_free(&stderr_buffer);
1567
1568         /* Report bytes transferred, and transfer rates. */
1569         total_time = get_current_time() - start_time;
1570         debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
1571             stdin_bytes, stdout_bytes, stderr_bytes, total_time);
1572         if (total_time > 0)
1573                 debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
1574                     stdin_bytes / total_time, stdout_bytes / total_time,
1575                     stderr_bytes / total_time);
1576
1577         /* Return the exit status of the program. */
1578         debug("Exit status %d", exit_status);
1579         return exit_status;
1580 }
1581
1582 /*********/
1583
1584 static void
1585 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1586 {
1587         u_int data_len;
1588         char *data = packet_get_string(&data_len);
1589         packet_check_eom();
1590         buffer_append(&stdout_buffer, data, data_len);
1591         memset(data, 0, data_len);
1592         xfree(data);
1593 }
1594 static void
1595 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1596 {
1597         u_int data_len;
1598         char *data = packet_get_string(&data_len);
1599         packet_check_eom();
1600         buffer_append(&stderr_buffer, data, data_len);
1601         memset(data, 0, data_len);
1602         xfree(data);
1603 }
1604 static void
1605 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1606 {
1607         exit_status = packet_get_int();
1608         packet_check_eom();
1609         /* Acknowledge the exit. */
1610         packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1611         packet_send();
1612         /*
1613          * Must wait for packet to be sent since we are
1614          * exiting the loop.
1615          */
1616         packet_write_wait();
1617         /* Flag that we want to exit. */
1618         quit_pending = 1;
1619 }
1620 static void
1621 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1622 {
1623         Channel *c = NULL;
1624         int remote_id, sock;
1625
1626         /* Read the remote channel number from the message. */
1627         remote_id = packet_get_int();
1628         packet_check_eom();
1629
1630         /*
1631          * Get a connection to the local authentication agent (this may again
1632          * get forwarded).
1633          */
1634         sock = ssh_get_authentication_socket();
1635
1636         /*
1637          * If we could not connect the agent, send an error message back to
1638          * the server. This should never happen unless the agent dies,
1639          * because authentication forwarding is only enabled if we have an
1640          * agent.
1641          */
1642         if (sock >= 0) {
1643                 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1644                     -1, 0, 0, 0, "authentication agent connection", 1);
1645                 c->remote_id = remote_id;
1646                 c->force_drain = 1;
1647         }
1648         if (c == NULL) {
1649                 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1650                 packet_put_int(remote_id);
1651         } else {
1652                 /* Send a confirmation to the remote host. */
1653                 debug("Forwarding authentication connection.");
1654                 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1655                 packet_put_int(remote_id);
1656                 packet_put_int(c->self);
1657         }
1658         packet_send();
1659 }
1660
1661 static Channel *
1662 client_request_forwarded_tcpip(const char *request_type, int rchan)
1663 {
1664         Channel *c = NULL;
1665         char *listen_address, *originator_address;
1666         int listen_port, originator_port;
1667         int sock;
1668
1669         /* Get rest of the packet */
1670         listen_address = packet_get_string(NULL);
1671         listen_port = packet_get_int();
1672         originator_address = packet_get_string(NULL);
1673         originator_port = packet_get_int();
1674         packet_check_eom();
1675
1676         debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1677             listen_address, listen_port, originator_address, originator_port);
1678
1679         sock = channel_connect_by_listen_address(listen_port);
1680         if (sock < 0) {
1681                 xfree(originator_address);
1682                 xfree(listen_address);
1683                 return NULL;
1684         }
1685         c = channel_new("forwarded-tcpip",
1686             SSH_CHANNEL_CONNECTING, sock, sock, -1,
1687             CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1688             originator_address, 1);
1689         xfree(originator_address);
1690         xfree(listen_address);
1691         return c;
1692 }
1693
1694 static Channel *
1695 client_request_x11(const char *request_type, int rchan)
1696 {
1697         Channel *c = NULL;
1698         char *originator;
1699         int originator_port;
1700         int sock;
1701
1702         if (!options.forward_x11) {
1703                 error("Warning: ssh server tried X11 forwarding.");
1704                 error("Warning: this is probably a break-in attempt by a malicious server.");
1705                 return NULL;
1706         }
1707         originator = packet_get_string(NULL);
1708         if (datafellows & SSH_BUG_X11FWD) {
1709                 debug2("buggy server: x11 request w/o originator_port");
1710                 originator_port = 0;
1711         } else {
1712                 originator_port = packet_get_int();
1713         }
1714         packet_check_eom();
1715         /* XXX check permission */
1716         debug("client_request_x11: request from %s %d", originator,
1717             originator_port);
1718         xfree(originator);
1719         sock = x11_connect_display();
1720         if (sock < 0)
1721                 return NULL;
1722         c = channel_new("x11",
1723             SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1724             CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1725         c->force_drain = 1;
1726         return c;
1727 }
1728
1729 static Channel *
1730 client_request_agent(const char *request_type, int rchan)
1731 {
1732         Channel *c = NULL;
1733         int sock;
1734
1735         if (!options.forward_agent) {
1736                 error("Warning: ssh server tried agent forwarding.");
1737                 error("Warning: this is probably a break-in attempt by a malicious server.");
1738                 return NULL;
1739         }
1740         sock =  ssh_get_authentication_socket();
1741         if (sock < 0)
1742                 return NULL;
1743         c = channel_new("authentication agent connection",
1744             SSH_CHANNEL_OPEN, sock, sock, -1,
1745             CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1746             "authentication agent connection", 1);
1747         c->force_drain = 1;
1748         return c;
1749 }
1750
1751 /* XXXX move to generic input handler */
1752 static void
1753 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1754 {
1755         Channel *c = NULL;
1756         char *ctype;
1757         int rchan;
1758         u_int rmaxpack, rwindow, len;
1759
1760         ctype = packet_get_string(&len);
1761         rchan = packet_get_int();
1762         rwindow = packet_get_int();
1763         rmaxpack = packet_get_int();
1764
1765         debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1766             ctype, rchan, rwindow, rmaxpack);
1767
1768         if (strcmp(ctype, "forwarded-tcpip") == 0) {
1769                 c = client_request_forwarded_tcpip(ctype, rchan);
1770         } else if (strcmp(ctype, "x11") == 0) {
1771                 c = client_request_x11(ctype, rchan);
1772         } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1773                 c = client_request_agent(ctype, rchan);
1774         }
1775 /* XXX duplicate : */
1776         if (c != NULL) {
1777                 debug("confirm %s", ctype);
1778                 c->remote_id = rchan;
1779                 c->remote_window = rwindow;
1780                 c->remote_maxpacket = rmaxpack;
1781                 if (c->type != SSH_CHANNEL_CONNECTING) {
1782                         packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1783                         packet_put_int(c->remote_id);
1784                         packet_put_int(c->self);
1785                         packet_put_int(c->local_window);
1786                         packet_put_int(c->local_maxpacket);
1787                         packet_send();
1788                 }
1789         } else {
1790                 debug("failure %s", ctype);
1791                 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1792                 packet_put_int(rchan);
1793                 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1794                 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1795                         packet_put_cstring("open failed");
1796                         packet_put_cstring("");
1797                 }
1798                 packet_send();
1799         }
1800         xfree(ctype);
1801 }
1802 static void
1803 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1804 {
1805         Channel *c = NULL;
1806         int exitval, id, reply, success = 0;
1807         char *rtype;
1808
1809         id = packet_get_int();
1810         rtype = packet_get_string(NULL);
1811         reply = packet_get_char();
1812
1813         debug("client_input_channel_req: channel %d rtype %s reply %d",
1814             id, rtype, reply);
1815
1816         if (id == -1) {
1817                 error("client_input_channel_req: request for channel -1");
1818         } else if ((c = channel_lookup(id)) == NULL) {
1819                 error("client_input_channel_req: channel %d: unknown channel", id);
1820         } else if (strcmp(rtype, "exit-status") == 0) {
1821                 exitval = packet_get_int();
1822                 if (id == session_ident) {
1823                         success = 1;
1824                         exit_status = exitval;
1825                 } else if (c->ctl_fd == -1) {
1826                         error("client_input_channel_req: unexpected channel %d",
1827                             session_ident);
1828                 } else {
1829                         atomicio(vwrite, c->ctl_fd, &exitval, sizeof(exitval));
1830                         success = 1;
1831                 }
1832                 packet_check_eom();
1833         }
1834         if (reply) {
1835                 packet_start(success ?
1836                     SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1837                 packet_put_int(id);
1838                 packet_send();
1839         }
1840         xfree(rtype);
1841 }
1842 static void
1843 client_input_global_request(int type, u_int32_t seq, void *ctxt)
1844 {
1845         char *rtype;
1846         int want_reply;
1847         int success = 0;
1848
1849         rtype = packet_get_string(NULL);
1850         want_reply = packet_get_char();
1851         debug("client_input_global_request: rtype %s want_reply %d",
1852             rtype, want_reply);
1853         if (want_reply) {
1854                 packet_start(success ?
1855                     SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1856                 packet_send();
1857                 packet_write_wait();
1858         }
1859         xfree(rtype);
1860 }
1861
1862 void
1863 client_session2_setup(int id, int want_tty, int want_subsystem,
1864     const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env,
1865     dispatch_fn *subsys_repl)
1866 {
1867         int len;
1868         Channel *c = NULL;
1869
1870         debug2("%s: id %d", __func__, id);
1871
1872         if ((c = channel_lookup(id)) == NULL)
1873                 fatal("client_session2_setup: channel %d: unknown channel", id);
1874
1875         if (want_tty) {
1876                 struct winsize ws;
1877                 struct termios tio;
1878
1879                 /* Store window size in the packet. */
1880                 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
1881                         memset(&ws, 0, sizeof(ws));
1882
1883                 channel_request_start(id, "pty-req", 0);
1884                 packet_put_cstring(term != NULL ? term : "");
1885                 packet_put_int((u_int)ws.ws_col);
1886                 packet_put_int((u_int)ws.ws_row);
1887                 packet_put_int((u_int)ws.ws_xpixel);
1888                 packet_put_int((u_int)ws.ws_ypixel);
1889                 tio = get_saved_tio();
1890                 tty_make_modes(-1, tiop != NULL ? tiop : &tio);
1891                 packet_send();
1892                 /* XXX wait for reply */
1893                 c->client_tty = 1;
1894         }
1895
1896         /* Transfer any environment variables from client to server */
1897         if (options.num_send_env != 0 && env != NULL) {
1898                 int i, j, matched;
1899                 char *name, *val;
1900
1901                 debug("Sending environment.");
1902                 for (i = 0; env[i] != NULL; i++) {
1903                         /* Split */
1904                         name = xstrdup(env[i]);
1905                         if ((val = strchr(name, '=')) == NULL) {
1906                                 xfree(name);
1907                                 continue;
1908                         }
1909                         *val++ = '\0';
1910
1911                         matched = 0;
1912                         for (j = 0; j < options.num_send_env; j++) {
1913                                 if (match_pattern(name, options.send_env[j])) {
1914                                         matched = 1;
1915                                         break;
1916                                 }
1917                         }
1918                         if (!matched) {
1919                                 debug3("Ignored env %s", name);
1920                                 xfree(name);
1921                                 continue;
1922                         }
1923
1924                         debug("Sending env %s = %s", name, val);
1925                         channel_request_start(id, "env", 0);
1926                         packet_put_cstring(name);
1927                         packet_put_cstring(val);
1928                         packet_send();
1929                         xfree(name);
1930                 }
1931         }
1932
1933         len = buffer_len(cmd);
1934         if (len > 0) {
1935                 if (len > 900)
1936                         len = 900;
1937                 if (want_subsystem) {
1938                         debug("Sending subsystem: %.*s", len, (u_char*)buffer_ptr(cmd));
1939                         channel_request_start(id, "subsystem", subsys_repl != NULL);
1940                         if (subsys_repl != NULL) {
1941                                 /* register callback for reply */
1942                                 /* XXX we assume that client_loop has already been called */
1943                                 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, subsys_repl);
1944                                 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, subsys_repl);
1945                         }
1946                 } else {
1947                         debug("Sending command: %.*s", len, (u_char*)buffer_ptr(cmd));
1948                         channel_request_start(id, "exec", 0);
1949                 }
1950                 packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
1951                 packet_send();
1952         } else {
1953                 channel_request_start(id, "shell", 0);
1954                 packet_send();
1955         }
1956 }
1957
1958 static void
1959 client_init_dispatch_20(void)
1960 {
1961         dispatch_init(&dispatch_protocol_error);
1962
1963         dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1964         dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1965         dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1966         dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1967         dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1968         dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1969         dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1970         dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1971         dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1972         dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1973
1974         /* rekeying */
1975         dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1976
1977         /* global request reply messages */
1978         dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
1979         dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1980 }
1981 static void
1982 client_init_dispatch_13(void)
1983 {
1984         dispatch_init(NULL);
1985         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1986         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1987         dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1988         dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1989         dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1990         dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1991         dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
1992         dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
1993         dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1994
1995         dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1996             &client_input_agent_open : &deny_input_open);
1997         dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
1998             &x11_input_open : &deny_input_open);
1999 }
2000 static void
2001 client_init_dispatch_15(void)
2002 {
2003         client_init_dispatch_13();
2004         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2005         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2006 }
2007 static void
2008 client_init_dispatch(void)
2009 {
2010         if (compat20)
2011                 client_init_dispatch_20();
2012         else if (compat13)
2013                 client_init_dispatch_13();
2014         else
2015                 client_init_dispatch_15();
2016 }
2017
2018 /* client specific fatal cleanup */
2019 void
2020 cleanup_exit(int i)
2021 {
2022         leave_raw_mode();
2023         leave_non_blocking();
2024         if (options.control_path != NULL && control_fd != -1)
2025                 unlink(options.control_path);
2026         _exit(i);
2027 }