clientloop.c

   1 /* $OpenBSD: clientloop.c,v 1.167 2006/07/11 18:50:47 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/socket.h>
  69 #include <sys/ioctl.h>
  70
  71 #include <ctype.h>
  72 #ifdef HAVE_PATHS_H
  73 #include <paths.h>
  74 #endif
  75 #include <signal.h>
  76 #include <termios.h>
  77
  78 #include "ssh.h"
  79 #include "ssh1.h"
  80 #include "ssh2.h"
  81 #include "xmalloc.h"
  82 #include "packet.h"
  83 #include "buffer.h"
  84 #include "compat.h"
  85 #include "channels.h"
  86 #include "dispatch.h"
  87 #include "buffer.h"
  88 #include "bufaux.h"
  89 #include "key.h"
  90 #include "kex.h"
  91 #include "log.h"
  92 #include "readconf.h"
  93 #include "clientloop.h"
  94 #include "sshconnect.h"
  95 #include "authfd.h"
  96 #include "atomicio.h"
  97 #include "sshpty.h"
  98 #include "misc.h"
  99 #include "monitor_fdpass.h"
 100 #include "match.h"
 101 #include "msg.h"
 102
 103 /* import options */
 104 extern Options options;
 105
 106 /* Flag indicating that stdin should be redirected from /dev/null. */
 107 extern int stdin_null_flag;
 108
 109 /* Flag indicating that no shell has been requested */
 110 extern int no_shell_flag;
 111
 112 /* Control socket */
 113 extern int control_fd;
 114
 115 /*
 116  * Name of the host we are connecting to.  This is the name given on the
 117  * command line, or the HostName specified for the user-supplied name in a
 118  * configuration file.
 119  */
 120 extern char *host;
 121
 122 /*
 123  * Flag to indicate that we have received a window change signal which has
 124  * not yet been processed.  This will cause a message indicating the new
 125  * window size to be sent to the server a little later.  This is volatile
 126  * because this is updated in a signal handler.
 127  */
 128 static volatile sig_atomic_t received_window_change_signal = 0;
 129 static volatile sig_atomic_t received_signal = 0;
 130
 131 /* Flag indicating whether the user's terminal is in non-blocking mode. */
 132 static int in_non_blocking_mode = 0;
 133
 134 /* Common data for the client loop code. */
 135 static volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
 136 static int escape_char;         /* Escape character. */
 137 static int escape_pending;      /* Last character was the escape character */
 138 static int last_was_cr;         /* Last character was a newline. */
 139 static int exit_status;         /* Used to store the exit status of the command. */
 140 static int stdin_eof;           /* EOF has been encountered on standard error. */
 141 static Buffer stdin_buffer;     /* Buffer for stdin data. */
 142 static Buffer stdout_buffer;    /* Buffer for stdout data. */
 143 static Buffer stderr_buffer;    /* Buffer for stderr data. */
 144 static u_long stdin_bytes, stdout_bytes, stderr_bytes;
 145 static u_int buffer_high;/* Soft max buffer size. */
 146 static int connection_in;       /* Connection to server (input). */
 147 static int connection_out;      /* Connection to server (output). */
 148 static int need_rekeying;       /* Set to non-zero if rekeying is requested. */
 149 static int session_closed = 0;  /* In SSH2: login session closed. */
 150 static int server_alive_timeouts = 0;
 151
 152 static void client_init_dispatch(void);
 153 int     session_ident = -1;
 154
 155 struct confirm_ctx {
 156         int want_tty;
 157         int want_subsys;
 158         int want_x_fwd;
 159         int want_agent_fwd;
 160         Buffer cmd;
 161         char *term;
 162         struct termios tio;
 163         char **env;
 164 };
 165
 166 /*XXX*/
 167 extern Kex *xxx_kex;
 168
 169 void ssh_process_session2_setup(int, int, int, Buffer *);
 170
 171 /* Restores stdin to blocking mode. */
 172
 173 static void
 174 leave_non_blocking(void)
 175 {
 176         if (in_non_blocking_mode) {
 177                 unset_nonblock(fileno(stdin));
 178                 in_non_blocking_mode = 0;
 179         }
 180 }
 181
 182 /* Puts stdin terminal in non-blocking mode. */
 183
 184 static void
 185 enter_non_blocking(void)
 186 {
 187         in_non_blocking_mode = 1;
 188         set_nonblock(fileno(stdin));
 189 }
 190
 191 /*
 192  * Signal handler for the window change signal (SIGWINCH).  This just sets a
 193  * flag indicating that the window has changed.
 194  */
 195 /*ARGSUSED */
 196 static void
 197 window_change_handler(int sig)
 198 {
 199         received_window_change_signal = 1;
 200         signal(SIGWINCH, window_change_handler);
 201 }
 202
 203 /*
 204  * Signal handler for signals that cause the program to terminate.  These
 205  * signals must be trapped to restore terminal modes.
 206  */
 207 /*ARGSUSED */
 208 static void
 209 signal_handler(int sig)
 210 {
 211         received_signal = sig;
 212         quit_pending = 1;
 213 }
 214
 215 /*
 216  * Returns current time in seconds from Jan 1, 1970 with the maximum
 217  * available resolution.
 218  */
 219
 220 static double
 221 get_current_time(void)
 222 {
 223         struct timeval tv;
 224         gettimeofday(&tv, NULL);
 225         return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
 226 }
 227
 228 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
 229 void
 230 client_x11_get_proto(const char *display, const char *xauth_path,
 231     u_int trusted, char **_proto, char **_data)
 232 {
 233         char cmd[1024];
 234         char line[512];
 235         char xdisplay[512];
 236         static char proto[512], data[512];
 237         FILE *f;
 238         int got_data = 0, generated = 0, do_unlink = 0, i;
 239         char *xauthdir, *xauthfile;
 240         struct stat st;
 241
 242         xauthdir = xauthfile = NULL;
 243         *_proto = proto;
 244         *_data = data;
 245         proto[0] = data[0] = '\0';
 246
 247         if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
 248                 debug("No xauth program.");
 249         } else {
 250                 if (display == NULL) {
 251                         debug("x11_get_proto: DISPLAY not set");
 252                         return;
 253                 }
 254                 /*
 255                  * Handle FamilyLocal case where $DISPLAY does
 256                  * not match an authorization entry.  For this we
 257                  * just try "xauth list unix:displaynum.screennum".
 258                  * XXX: "localhost" match to determine FamilyLocal
 259                  *      is not perfect.
 260                  */
 261                 if (strncmp(display, "localhost:", 10) == 0) {
 262                         snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
 263                             display + 10);
 264                         display = xdisplay;
 265                 }
 266                 if (trusted == 0) {
 267                         xauthdir = xmalloc(MAXPATHLEN);
 268                         xauthfile = xmalloc(MAXPATHLEN);
 269                         strlcpy(xauthdir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
 270                         if (mkdtemp(xauthdir) != NULL) {
 271                                 do_unlink = 1;
 272                                 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
 273                                     xauthdir);
 274                                 snprintf(cmd, sizeof(cmd),
 275                                     "%s -f %s generate %s " SSH_X11_PROTO
 276                                     " untrusted timeout 1200 2>" _PATH_DEVNULL,
 277                                     xauth_path, xauthfile, display);
 278                                 debug2("x11_get_proto: %s", cmd);
 279                                 if (system(cmd) == 0)
 280                                         generated = 1;
 281                         }
 282                 }
 283                 snprintf(cmd, sizeof(cmd),
 284                     "%s %s%s list %s 2>" _PATH_DEVNULL,
 285                     xauth_path,
 286                     generated ? "-f " : "" ,
 287                     generated ? xauthfile : "",
 288                     display);
 289                 debug2("x11_get_proto: %s", cmd);
 290                 f = popen(cmd, "r");
 291                 if (f && fgets(line, sizeof(line), f) &&
 292                     sscanf(line, "%*s %511s %511s", proto, data) == 2)
 293                         got_data = 1;
 294                 if (f)
 295                         pclose(f);
 296         }
 297
 298         if (do_unlink) {
 299                 unlink(xauthfile);
 300                 rmdir(xauthdir);
 301         }
 302         if (xauthdir)
 303                 xfree(xauthdir);
 304         if (xauthfile)
 305                 xfree(xauthfile);
 306
 307         /*
 308          * If we didn't get authentication data, just make up some
 309          * data.  The forwarding code will check the validity of the
 310          * response anyway, and substitute this data.  The X11
 311          * server, however, will ignore this fake data and use
 312          * whatever authentication mechanisms it was using otherwise
 313          * for the local connection.
 314          */
 315         if (!got_data) {
 316                 u_int32_t rnd = 0;
 317
 318                 logit("Warning: No xauth data; "
 319                     "using fake authentication data for X11 forwarding.");
 320                 strlcpy(proto, SSH_X11_PROTO, sizeof proto);
 321                 for (i = 0; i < 16; i++) {
 322                         if (i % 4 == 0)
 323                                 rnd = arc4random();
 324                         snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
 325                             rnd & 0xff);
 326                         rnd >>= 8;
 327                 }
 328         }
 329 }
 330
 331 /*
 332  * This is called when the interactive is entered.  This checks if there is
 333  * an EOF coming on stdin.  We must check this explicitly, as select() does
 334  * not appear to wake up when redirecting from /dev/null.
 335  */
 336
 337 static void
 338 client_check_initial_eof_on_stdin(void)
 339 {
 340         int len;
 341         char buf[1];
 342
 343         /*
 344          * If standard input is to be "redirected from /dev/null", we simply
 345          * mark that we have seen an EOF and send an EOF message to the
 346          * server. Otherwise, we try to read a single character; it appears
 347          * that for some files, such /dev/null, select() never wakes up for
 348          * read for this descriptor, which means that we never get EOF.  This
 349          * way we will get the EOF if stdin comes from /dev/null or similar.
 350          */
 351         if (stdin_null_flag) {
 352                 /* Fake EOF on stdin. */
 353                 debug("Sending eof.");
 354                 stdin_eof = 1;
 355                 packet_start(SSH_CMSG_EOF);
 356                 packet_send();
 357         } else {
 358                 enter_non_blocking();
 359
 360                 /* Check for immediate EOF on stdin. */
 361                 len = read(fileno(stdin), buf, 1);
 362                 if (len == 0) {
 363                         /* EOF.  Record that we have seen it and send EOF to server. */
 364                         debug("Sending eof.");
 365                         stdin_eof = 1;
 366                         packet_start(SSH_CMSG_EOF);
 367                         packet_send();
 368                 } else if (len > 0) {
 369                         /*
 370                          * Got data.  We must store the data in the buffer,
 371                          * and also process it as an escape character if
 372                          * appropriate.
 373                          */
 374                         if ((u_char) buf[0] == escape_char)
 375                                 escape_pending = 1;
 376                         else
 377                                 buffer_append(&stdin_buffer, buf, 1);
 378                 }
 379                 leave_non_blocking();
 380         }
 381 }
 382
 383
 384 /*
 385  * Make packets from buffered stdin data, and buffer them for sending to the
 386  * connection.
 387  */
 388
 389 static void
 390 client_make_packets_from_stdin_data(void)
 391 {
 392         u_int len;
 393
 394         /* Send buffered stdin data to the server. */
 395         while (buffer_len(&stdin_buffer) > 0 &&
 396             packet_not_very_much_data_to_write()) {
 397                 len = buffer_len(&stdin_buffer);
 398                 /* Keep the packets at reasonable size. */
 399                 if (len > packet_get_maxsize())
 400                         len = packet_get_maxsize();
 401                 packet_start(SSH_CMSG_STDIN_DATA);
 402                 packet_put_string(buffer_ptr(&stdin_buffer), len);
 403                 packet_send();
 404                 buffer_consume(&stdin_buffer, len);
 405                 stdin_bytes += len;
 406                 /* If we have a pending EOF, send it now. */
 407                 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
 408                         packet_start(SSH_CMSG_EOF);
 409                         packet_send();
 410                 }
 411         }
 412 }
 413
 414 /*
 415  * Checks if the client window has changed, and sends a packet about it to
 416  * the server if so.  The actual change is detected elsewhere (by a software
 417  * interrupt on Unix); this just checks the flag and sends a message if
 418  * appropriate.
 419  */
 420
 421 static void
 422 client_check_window_change(void)
 423 {
 424         struct winsize ws;
 425
 426         if (! received_window_change_signal)
 427                 return;
 428         /** XXX race */
 429         received_window_change_signal = 0;
 430
 431         debug2("client_check_window_change: changed");
 432
 433         if (compat20) {
 434                 channel_send_window_changes();
 435         } else {
 436                 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
 437                         return;
 438                 packet_start(SSH_CMSG_WINDOW_SIZE);
 439                 packet_put_int((u_int)ws.ws_row);
 440                 packet_put_int((u_int)ws.ws_col);
 441                 packet_put_int((u_int)ws.ws_xpixel);
 442                 packet_put_int((u_int)ws.ws_ypixel);
 443                 packet_send();
 444         }
 445 }
 446
 447 static void
 448 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
 449 {
 450         server_alive_timeouts = 0;
 451         client_global_request_reply_fwd(type, seq, ctxt);
 452 }
 453
 454 static void
 455 server_alive_check(void)
 456 {
 457         if (++server_alive_timeouts > options.server_alive_count_max)
 458                 packet_disconnect("Timeout, server not responding.");
 459         packet_start(SSH2_MSG_GLOBAL_REQUEST);
 460         packet_put_cstring("keepalive@openssh.com");
 461         packet_put_char(1);     /* boolean: want reply */
 462         packet_send();
 463 }
 464
 465 /*
 466  * Waits until the client can do something (some data becomes available on
 467  * one of the file descriptors).
 468  */
 469 static void
 470 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
 471     int *maxfdp, u_int *nallocp, int rekeying)
 472 {
 473         struct timeval tv, *tvp;
 474         int ret;
 475
 476         /* Add any selections by the channel mechanism. */
 477         channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
 478
 479         if (!compat20) {
 480                 /* Read from the connection, unless our buffers are full. */
 481                 if (buffer_len(&stdout_buffer) < buffer_high &&
 482                     buffer_len(&stderr_buffer) < buffer_high &&
 483                     channel_not_very_much_buffered_data())
 484                         FD_SET(connection_in, *readsetp);
 485                 /*
 486                  * Read from stdin, unless we have seen EOF or have very much
 487                  * buffered data to send to the server.
 488                  */
 489                 if (!stdin_eof && packet_not_very_much_data_to_write())
 490                         FD_SET(fileno(stdin), *readsetp);
 491
 492                 /* Select stdout/stderr if have data in buffer. */
 493                 if (buffer_len(&stdout_buffer) > 0)
 494                         FD_SET(fileno(stdout), *writesetp);
 495                 if (buffer_len(&stderr_buffer) > 0)
 496                         FD_SET(fileno(stderr), *writesetp);
 497         } else {
 498                 /* channel_prepare_select could have closed the last channel */
 499                 if (session_closed && !channel_still_open() &&
 500                     !packet_have_data_to_write()) {
 501                         /* clear mask since we did not call select() */
 502                         memset(*readsetp, 0, *nallocp);
 503                         memset(*writesetp, 0, *nallocp);
 504                         return;
 505                 } else {
 506                         FD_SET(connection_in, *readsetp);
 507                 }
 508         }
 509
 510         /* Select server connection if have data to write to the server. */
 511         if (packet_have_data_to_write())
 512                 FD_SET(connection_out, *writesetp);
 513
 514         if (control_fd != -1)
 515                 FD_SET(control_fd, *readsetp);
 516
 517         /*
 518          * Wait for something to happen.  This will suspend the process until
 519          * some selected descriptor can be read, written, or has some other
 520          * event pending.
 521          */
 522
 523         if (options.server_alive_interval == 0 || !compat20)
 524                 tvp = NULL;
 525         else {
 526                 tv.tv_sec = options.server_alive_interval;
 527                 tv.tv_usec = 0;
 528                 tvp = &tv;
 529         }
 530         ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
 531         if (ret < 0) {
 532                 char buf[100];
 533
 534                 /*
 535                  * We have to clear the select masks, because we return.
 536                  * We have to return, because the mainloop checks for the flags
 537                  * set by the signal handlers.
 538                  */
 539                 memset(*readsetp, 0, *nallocp);
 540                 memset(*writesetp, 0, *nallocp);
 541
 542                 if (errno == EINTR)
 543                         return;
 544                 /* Note: we might still have data in the buffers. */
 545                 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
 546                 buffer_append(&stderr_buffer, buf, strlen(buf));
 547                 quit_pending = 1;
 548         } else if (ret == 0)
 549                 server_alive_check();
 550 }
 551
 552 static void
 553 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
 554 {
 555         /* Flush stdout and stderr buffers. */
 556         if (buffer_len(bout) > 0)
 557                 atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
 558         if (buffer_len(berr) > 0)
 559                 atomicio(vwrite, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
 560
 561         leave_raw_mode();
 562
 563         /*
 564          * Free (and clear) the buffer to reduce the amount of data that gets
 565          * written to swap.
 566          */
 567         buffer_free(bin);
 568         buffer_free(bout);
 569         buffer_free(berr);
 570
 571         /* Send the suspend signal to the program itself. */
 572         kill(getpid(), SIGTSTP);
 573
 574         /* Reset window sizes in case they have changed */
 575         received_window_change_signal = 1;
 576
 577         /* OK, we have been continued by the user. Reinitialize buffers. */
 578         buffer_init(bin);
 579         buffer_init(bout);
 580         buffer_init(berr);
 581
 582         enter_raw_mode();
 583 }
 584
 585 static void
 586 client_process_net_input(fd_set *readset)
 587 {
 588         int len;
 589         char buf[8192];
 590
 591         /*
 592          * Read input from the server, and add any such data to the buffer of
 593          * the packet subsystem.
 594          */
 595         if (FD_ISSET(connection_in, readset)) {
 596                 /* Read as much as possible. */
 597                 len = read(connection_in, buf, sizeof(buf));
 598                 if (len == 0) {
 599                         /* Received EOF.  The remote host has closed the connection. */
 600                         snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
 601                                  host);
 602                         buffer_append(&stderr_buffer, buf, strlen(buf));
 603                         quit_pending = 1;
 604                         return;
 605                 }
 606                 /*
 607                  * There is a kernel bug on Solaris that causes select to
 608                  * sometimes wake up even though there is no data available.
 609                  */
 610                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
 611                         len = 0;
 612
 613                 if (len < 0) {
 614                         /* An error has encountered.  Perhaps there is a network problem. */
 615                         snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
 616                                  host, strerror(errno));
 617                         buffer_append(&stderr_buffer, buf, strlen(buf));
 618                         quit_pending = 1;
 619                         return;
 620                 }
 621                 packet_process_incoming(buf, len);
 622         }
 623 }
 624
 625 static void
 626 client_subsystem_reply(int type, u_int32_t seq, void *ctxt)
 627 {
 628         int id;
 629         Channel *c;
 630
 631         id = packet_get_int();
 632         packet_check_eom();
 633
 634         if ((c = channel_lookup(id)) == NULL) {
 635                 error("%s: no channel for id %d", __func__, id);
 636                 return;
 637         }
 638
 639         if (type == SSH2_MSG_CHANNEL_SUCCESS)
 640                 debug2("Request suceeded on channel %d", id);
 641         else if (type == SSH2_MSG_CHANNEL_FAILURE) {
 642                 error("Request failed on channel %d", id);
 643                 channel_free(c);
 644         }
 645 }
 646
 647 static void
 648 client_extra_session2_setup(int id, void *arg)
 649 {
 650         struct confirm_ctx *cctx = arg;
 651         const char *display;
 652         Channel *c;
 653         int i;
 654
 655         if (cctx == NULL)
 656                 fatal("%s: cctx == NULL", __func__);
 657         if ((c = channel_lookup(id)) == NULL)
 658                 fatal("%s: no channel for id %d", __func__, id);
 659
 660         display = getenv("DISPLAY");
 661         if (cctx->want_x_fwd && options.forward_x11 && display != NULL) {
 662                 char *proto, *data;
 663                 /* Get reasonable local authentication information. */
 664                 client_x11_get_proto(display, options.xauth_location,
 665                     options.forward_x11_trusted, &proto, &data);
 666                 /* Request forwarding with authentication spoofing. */
 667                 debug("Requesting X11 forwarding with authentication spoofing.");
 668                 x11_request_forwarding_with_spoofing(id, display, proto, data);
 669                 /* XXX wait for reply */
 670         }
 671
 672         if (cctx->want_agent_fwd && options.forward_agent) {
 673                 debug("Requesting authentication agent forwarding.");
 674                 channel_request_start(id, "auth-agent-req@openssh.com", 0);
 675                 packet_send();
 676         }
 677
 678         client_session2_setup(id, cctx->want_tty, cctx->want_subsys,
 679             cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env,
 680             client_subsystem_reply);
 681
 682         c->confirm_ctx = NULL;
 683         buffer_free(&cctx->cmd);
 684         xfree(cctx->term);
 685         if (cctx->env != NULL) {
 686                 for (i = 0; cctx->env[i] != NULL; i++)
 687                         xfree(cctx->env[i]);
 688                 xfree(cctx->env);
 689         }
 690         xfree(cctx);
 691 }
 692
 693 static void
 694 client_process_control(fd_set *readset)
 695 {
 696         Buffer m;
 697         Channel *c;
 698         int client_fd, new_fd[3], ver, allowed;
 699         socklen_t addrlen;
 700         struct sockaddr_storage addr;
 701         struct confirm_ctx *cctx;
 702         char *cmd;
 703         u_int i, len, env_len, command, flags;
 704         uid_t euid;
 705         gid_t egid;
 706
 707         /*
 708          * Accept connection on control socket
 709          */
 710         if (control_fd == -1 || !FD_ISSET(control_fd, readset))
 711                 return;
 712
 713         memset(&addr, 0, sizeof(addr));
 714         addrlen = sizeof(addr);
 715         if ((client_fd = accept(control_fd,
 716             (struct sockaddr*)&addr, &addrlen)) == -1) {
 717                 error("%s accept: %s", __func__, strerror(errno));
 718                 return;
 719         }
 720
 721         if (getpeereid(client_fd, &euid, &egid) < 0) {
 722                 error("%s getpeereid failed: %s", __func__, strerror(errno));
 723                 close(client_fd);
 724                 return;
 725         }
 726         if ((euid != 0) && (getuid() != euid)) {
 727                 error("control mode uid mismatch: peer euid %u != uid %u",
 728                     (u_int) euid, (u_int) getuid());
 729                 close(client_fd);
 730                 return;
 731         }
 732
 733         unset_nonblock(client_fd);
 734
 735         /* Read command */
 736         buffer_init(&m);
 737         if (ssh_msg_recv(client_fd, &m) == -1) {
 738                 error("%s: client msg_recv failed", __func__);
 739                 close(client_fd);
 740                 buffer_free(&m);
 741                 return;
 742         }
 743         if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
 744                 error("%s: wrong client version %d", __func__, ver);
 745                 buffer_free(&m);
 746                 close(client_fd);
 747                 return;
 748         }
 749
 750         allowed = 1;
 751         command = buffer_get_int(&m);
 752         flags = buffer_get_int(&m);
 753
 754         buffer_clear(&m);
 755
 756         switch (command) {
 757         case SSHMUX_COMMAND_OPEN:
 758                 if (options.control_master == SSHCTL_MASTER_ASK ||
 759                     options.control_master == SSHCTL_MASTER_AUTO_ASK)
 760                         allowed = ask_permission("Allow shared connection "
 761                             "to %s? ", host);
 762                 /* continue below */
 763                 break;
 764         case SSHMUX_COMMAND_TERMINATE:
 765                 if (options.control_master == SSHCTL_MASTER_ASK ||
 766                     options.control_master == SSHCTL_MASTER_AUTO_ASK)
 767                         allowed = ask_permission("Terminate shared connection "
 768                             "to %s? ", host);
 769                 if (allowed)
 770                         quit_pending = 1;
 771                 /* FALLTHROUGH */
 772         case SSHMUX_COMMAND_ALIVE_CHECK:
 773                 /* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */
 774                 buffer_clear(&m);
 775                 buffer_put_int(&m, allowed);
 776                 buffer_put_int(&m, getpid());
 777                 if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 778                         error("%s: client msg_send failed", __func__);
 779                         close(client_fd);
 780                         buffer_free(&m);
 781                         return;
 782                 }
 783                 buffer_free(&m);
 784                 close(client_fd);
 785                 return;
 786         default:
 787                 error("Unsupported command %d", command);
 788                 buffer_free(&m);
 789                 close(client_fd);
 790                 return;
 791         }
 792
 793         /* Reply for SSHMUX_COMMAND_OPEN */
 794         buffer_clear(&m);
 795         buffer_put_int(&m, allowed);
 796         buffer_put_int(&m, getpid());
 797         if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 798                 error("%s: client msg_send failed", __func__);
 799                 close(client_fd);
 800                 buffer_free(&m);
 801                 return;
 802         }
 803
 804         if (!allowed) {
 805                 error("Refused control connection");
 806                 close(client_fd);
 807                 buffer_free(&m);
 808                 return;
 809         }
 810
 811         buffer_clear(&m);
 812         if (ssh_msg_recv(client_fd, &m) == -1) {
 813                 error("%s: client msg_recv failed", __func__);
 814                 close(client_fd);
 815                 buffer_free(&m);
 816                 return;
 817         }
 818         if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
 819                 error("%s: wrong client version %d", __func__, ver);
 820                 buffer_free(&m);
 821                 close(client_fd);
 822                 return;
 823         }
 824
 825         cctx = xcalloc(1, sizeof(*cctx));
 826         cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0;
 827         cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0;
 828         cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0;
 829         cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0;
 830         cctx->term = buffer_get_string(&m, &len);
 831
 832         cmd = buffer_get_string(&m, &len);
 833         buffer_init(&cctx->cmd);
 834         buffer_append(&cctx->cmd, cmd, strlen(cmd));
 835
 836         env_len = buffer_get_int(&m);
 837         env_len = MIN(env_len, 4096);
 838         debug3("%s: receiving %d env vars", __func__, env_len);
 839         if (env_len != 0) {
 840                 cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env));
 841                 for (i = 0; i < env_len; i++)
 842                         cctx->env[i] = buffer_get_string(&m, &len);
 843                 cctx->env[i] = NULL;
 844         }
 845
 846         debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__,
 847             cctx->want_tty, cctx->want_subsys, cmd);
 848         xfree(cmd);
 849
 850         /* Gather fds from client */
 851         new_fd[0] = mm_receive_fd(client_fd);
 852         new_fd[1] = mm_receive_fd(client_fd);
 853         new_fd[2] = mm_receive_fd(client_fd);
 854
 855         debug2("%s: got fds stdin %d, stdout %d, stderr %d", __func__,
 856             new_fd[0], new_fd[1], new_fd[2]);
 857
 858         /* Try to pick up ttymodes from client before it goes raw */
 859         if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1)
 860                 error("%s: tcgetattr: %s", __func__, strerror(errno));
 861
 862         /* This roundtrip is just for synchronisation of ttymodes */
 863         buffer_clear(&m);
 864         if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 865                 error("%s: client msg_send failed", __func__);
 866                 close(client_fd);
 867                 close(new_fd[0]);
 868                 close(new_fd[1]);
 869                 close(new_fd[2]);
 870                 buffer_free(&m);
 871                 xfree(cctx->term);
 872                 if (env_len != 0) {
 873                         for (i = 0; i < env_len; i++)
 874                                 xfree(cctx->env[i]);
 875                         xfree(cctx->env);
 876                 }
 877                 return;
 878         }
 879         buffer_free(&m);
 880
 881         /* enable nonblocking unless tty */
 882         if (!isatty(new_fd[0]))
 883                 set_nonblock(new_fd[0]);
 884         if (!isatty(new_fd[1]))
 885                 set_nonblock(new_fd[1]);
 886         if (!isatty(new_fd[2]))
 887                 set_nonblock(new_fd[2]);
 888
 889         set_nonblock(client_fd);
 890
 891         c = channel_new("session", SSH_CHANNEL_OPENING,
 892             new_fd[0], new_fd[1], new_fd[2],
 893             CHAN_SES_WINDOW_DEFAULT, CHAN_SES_PACKET_DEFAULT,
 894             CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0);
 895
 896         /* XXX */
 897         c->ctl_fd = client_fd;
 898
 899         debug3("%s: channel_new: %d", __func__, c->self);
 900
 901         channel_send_open(c->self);
 902         channel_register_confirm(c->self, client_extra_session2_setup, cctx);
 903 }
 904
 905 static void
 906 process_cmdline(void)
 907 {
 908         void (*handler)(int);
 909         char *s, *cmd, *cancel_host;
 910         int delete = 0;
 911         int local = 0;
 912         u_short cancel_port;
 913         Forward fwd;
 914
 915         leave_raw_mode();
 916         handler = signal(SIGINT, SIG_IGN);
 917         cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
 918         if (s == NULL)
 919                 goto out;
 920         while (*s && isspace(*s))
 921                 s++;
 922         if (*s == '-')
 923                 s++;    /* Skip cmdline '-', if any */
 924         if (*s == '\0')
 925                 goto out;
 926
 927         if (*s == 'h' || *s == 'H' || *s == '?') {
 928                 logit("Commands:");
 929                 logit("      -L[bind_address:]port:host:hostport    "
 930                     "Request local forward");
 931                 logit("      -R[bind_address:]port:host:hostport    "
 932                     "Request remote forward");
 933                 logit("      -KR[bind_address:]port                 "
 934                     "Cancel remote forward");
 935                 if (!options.permit_local_command)
 936                         goto out;
 937                 logit("      !args                                  "
 938                     "Execute local command");
 939                 goto out;
 940         }
 941
 942         if (*s == '!' && options.permit_local_command) {
 943                 s++;
 944                 ssh_local_cmd(s);
 945                 goto out;
 946         }
 947
 948         if (*s == 'K') {
 949                 delete = 1;
 950                 s++;
 951         }
 952         if (*s != 'L' && *s != 'R') {
 953                 logit("Invalid command.");
 954                 goto out;
 955         }
 956         if (*s == 'L')
 957                 local = 1;
 958         if (local && delete) {
 959                 logit("Not supported.");
 960                 goto out;
 961         }
 962         if ((!local || delete) && !compat20) {
 963                 logit("Not supported for SSH protocol version 1.");
 964                 goto out;
 965         }
 966
 967         s++;
 968         while (*s && isspace(*s))
 969                 s++;
 970
 971         if (delete) {
 972                 cancel_port = 0;
 973                 cancel_host = hpdelim(&s);      /* may be NULL */
 974                 if (s != NULL) {
 975                         cancel_port = a2port(s);
 976                         cancel_host = cleanhostname(cancel_host);
 977                 } else {
 978                         cancel_port = a2port(cancel_host);
 979                         cancel_host = NULL;
 980                 }
 981                 if (cancel_port == 0) {
 982                         logit("Bad forwarding close port");
 983                         goto out;
 984                 }
 985                 channel_request_rforward_cancel(cancel_host, cancel_port);
 986         } else {
 987                 if (!parse_forward(&fwd, s)) {
 988                         logit("Bad forwarding specification.");
 989                         goto out;
 990                 }
 991                 if (local) {
 992                         if (channel_setup_local_fwd_listener(fwd.listen_host,
 993                             fwd.listen_port, fwd.connect_host,
 994                             fwd.connect_port, options.gateway_ports) < 0) {
 995                                 logit("Port forwarding failed.");
 996                                 goto out;
 997                         }
 998                 } else {
 999                         if (channel_request_remote_forwarding(fwd.listen_host,
1000                             fwd.listen_port, fwd.connect_host,
1001                             fwd.connect_port) < 0) {
1002                                 logit("Port forwarding failed.");
1003                                 goto out;
1004                         }
1005                 }
1006
1007                 logit("Forwarding port.");
1008         }
1009
1010 out:
1011         signal(SIGINT, handler);
1012         enter_raw_mode();
1013         if (cmd)
1014                 xfree(cmd);
1015 }
1016
1017 /* process the characters one by one */
1018 static int
1019 process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
1020 {
1021         char string[1024];
1022         pid_t pid;
1023         int bytes = 0;
1024         u_int i;
1025         u_char ch;
1026         char *s;
1027
1028         if (len <= 0)
1029                 return (0);
1030
1031         for (i = 0; i < (u_int)len; i++) {
1032                 /* Get one character at a time. */
1033                 ch = buf[i];
1034
1035                 if (escape_pending) {
1036                         /* We have previously seen an escape character. */
1037                         /* Clear the flag now. */
1038                         escape_pending = 0;
1039
1040                         /* Process the escaped character. */
1041                         switch (ch) {
1042                         case '.':
1043                                 /* Terminate the connection. */
1044                                 snprintf(string, sizeof string, "%c.\r\n", escape_char);
1045                                 buffer_append(berr, string, strlen(string));
1046
1047                                 quit_pending = 1;
1048                                 return -1;
1049
1050                         case 'Z' - 64:
1051                                 /* Suspend the program. */
1052                                 /* Print a message to that effect to the user. */
1053                                 snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
1054                                 buffer_append(berr, string, strlen(string));
1055
1056                                 /* Restore terminal modes and suspend. */
1057                                 client_suspend_self(bin, bout, berr);
1058
1059                                 /* We have been continued. */
1060                                 continue;
1061
1062                         case 'B':
1063                                 if (compat20) {
1064                                         snprintf(string, sizeof string,
1065                                             "%cB\r\n", escape_char);
1066                                         buffer_append(berr, string,
1067                                             strlen(string));
1068                                         channel_request_start(session_ident,
1069                                             "break", 0);
1070                                         packet_put_int(1000);
1071                                         packet_send();
1072                                 }
1073                                 continue;
1074
1075                         case 'R':
1076                                 if (compat20) {
1077                                         if (datafellows & SSH_BUG_NOREKEY)
1078                                                 logit("Server does not support re-keying");
1079                                         else
1080                                                 need_rekeying = 1;
1081                                 }
1082                                 continue;
1083
1084                         case '&':
1085                                 /*
1086                                  * Detach the program (continue to serve connections,
1087                                  * but put in background and no more new connections).
1088                                  */
1089                                 /* Restore tty modes. */
1090                                 leave_raw_mode();
1091
1092                                 /* Stop listening for new connections. */
1093                                 channel_stop_listening();
1094
1095                                 snprintf(string, sizeof string,
1096                                     "%c& [backgrounded]\n", escape_char);
1097                                 buffer_append(berr, string, strlen(string));
1098
1099                                 /* Fork into background. */
1100                                 pid = fork();
1101                                 if (pid < 0) {
1102                                         error("fork: %.100s", strerror(errno));
1103                                         continue;
1104                                 }
1105                                 if (pid != 0) { /* This is the parent. */
1106                                         /* The parent just exits. */
1107                                         exit(0);
1108                                 }
1109                                 /* The child continues serving connections. */
1110                                 if (compat20) {
1111                                         buffer_append(bin, "\004", 1);
1112                                         /* fake EOF on stdin */
1113                                         return -1;
1114                                 } else if (!stdin_eof) {
1115                                         /*
1116                                          * Sending SSH_CMSG_EOF alone does not always appear
1117                                          * to be enough.  So we try to send an EOF character
1118                                          * first.
1119                                          */
1120                                         packet_start(SSH_CMSG_STDIN_DATA);
1121                                         packet_put_string("\004", 1);
1122                                         packet_send();
1123                                         /* Close stdin. */
1124                                         stdin_eof = 1;
1125                                         if (buffer_len(bin) == 0) {
1126                                                 packet_start(SSH_CMSG_EOF);
1127                                                 packet_send();
1128                                         }
1129                                 }
1130                                 continue;
1131
1132                         case '?':
1133                                 snprintf(string, sizeof string,
1134 "%c?\r\n\
1135 Supported escape sequences:\r\n\
1136 %c.  - terminate connection\r\n\
1137 %cB  - send a BREAK to the remote system\r\n\
1138 %cC  - open a command line\r\n\
1139 %cR  - Request rekey (SSH protocol 2 only)\r\n\
1140 %c^Z - suspend ssh\r\n\
1141 %c#  - list forwarded connections\r\n\
1142 %c&  - background ssh (when waiting for connections to terminate)\r\n\
1143 %c?  - this message\r\n\
1144 %c%c  - send the escape character by typing it twice\r\n\
1145 (Note that escapes are only recognized immediately after newline.)\r\n",
1146                                     escape_char, escape_char, escape_char, escape_char,
1147                                     escape_char, escape_char, escape_char, escape_char,
1148                                     escape_char, escape_char, escape_char);
1149                                 buffer_append(berr, string, strlen(string));
1150                                 continue;
1151
1152                         case '#':
1153                                 snprintf(string, sizeof string, "%c#\r\n", escape_char);
1154                                 buffer_append(berr, string, strlen(string));
1155                                 s = channel_open_message();
1156                                 buffer_append(berr, s, strlen(s));
1157                                 xfree(s);
1158                                 continue;
1159
1160                         case 'C':
1161                                 process_cmdline();
1162                                 continue;
1163
1164                         default:
1165                                 if (ch != escape_char) {
1166                                         buffer_put_char(bin, escape_char);
1167                                         bytes++;
1168                                 }
1169                                 /* Escaped characters fall through here */
1170                                 break;
1171                         }
1172                 } else {
1173                         /*
1174                          * The previous character was not an escape char. Check if this
1175                          * is an escape.
1176                          */
1177                         if (last_was_cr && ch == escape_char) {
1178                                 /* It is. Set the flag and continue to next character. */
1179                                 escape_pending = 1;
1180                                 continue;
1181                         }
1182                 }
1183
1184                 /*
1185                  * Normal character.  Record whether it was a newline,
1186                  * and append it to the buffer.
1187                  */
1188                 last_was_cr = (ch == '\r' || ch == '\n');
1189                 buffer_put_char(bin, ch);
1190                 bytes++;
1191         }
1192         return bytes;
1193 }
1194
1195 static void
1196 client_process_input(fd_set *readset)
1197 {
1198         int len;
1199         char buf[8192];
1200
1201         /* Read input from stdin. */
1202         if (FD_ISSET(fileno(stdin), readset)) {
1203                 /* Read as much as possible. */
1204                 len = read(fileno(stdin), buf, sizeof(buf));
1205                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
1206                         return;         /* we'll try again later */
1207                 if (len <= 0) {
1208                         /*
1209                          * Received EOF or error.  They are treated
1210                          * similarly, except that an error message is printed
1211                          * if it was an error condition.
1212                          */
1213                         if (len < 0) {
1214                                 snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
1215                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1216                         }
1217                         /* Mark that we have seen EOF. */
1218                         stdin_eof = 1;
1219                         /*
1220                          * Send an EOF message to the server unless there is
1221                          * data in the buffer.  If there is data in the
1222                          * buffer, no message will be sent now.  Code
1223                          * elsewhere will send the EOF when the buffer
1224                          * becomes empty if stdin_eof is set.
1225                          */
1226                         if (buffer_len(&stdin_buffer) == 0) {
1227                                 packet_start(SSH_CMSG_EOF);
1228                                 packet_send();
1229                         }
1230                 } else if (escape_char == SSH_ESCAPECHAR_NONE) {
1231                         /*
1232                          * Normal successful read, and no escape character.
1233                          * Just append the data to buffer.
1234                          */
1235                         buffer_append(&stdin_buffer, buf, len);
1236                 } else {
1237                         /*
1238                          * Normal, successful read.  But we have an escape character
1239                          * and have to process the characters one by one.
1240                          */
1241                         if (process_escapes(&stdin_buffer, &stdout_buffer,
1242                             &stderr_buffer, buf, len) == -1)
1243                                 return;
1244                 }
1245         }
1246 }
1247
1248 static void
1249 client_process_output(fd_set *writeset)
1250 {
1251         int len;
1252         char buf[100];
1253
1254         /* Write buffered output to stdout. */
1255         if (FD_ISSET(fileno(stdout), writeset)) {
1256                 /* Write as much data as possible. */
1257                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1258                     buffer_len(&stdout_buffer));
1259                 if (len <= 0) {
1260                         if (errno == EINTR || errno == EAGAIN)
1261                                 len = 0;
1262                         else {
1263                                 /*
1264                                  * An error or EOF was encountered.  Put an
1265                                  * error message to stderr buffer.
1266                                  */
1267                                 snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
1268                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1269                                 quit_pending = 1;
1270                                 return;
1271                         }
1272                 }
1273                 /* Consume printed data from the buffer. */
1274                 buffer_consume(&stdout_buffer, len);
1275                 stdout_bytes += len;
1276         }
1277         /* Write buffered output to stderr. */
1278         if (FD_ISSET(fileno(stderr), writeset)) {
1279                 /* Write as much data as possible. */
1280                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1281                     buffer_len(&stderr_buffer));
1282                 if (len <= 0) {
1283                         if (errno == EINTR || errno == EAGAIN)
1284                                 len = 0;
1285                         else {
1286                                 /* EOF or error, but can't even print error message. */
1287                                 quit_pending = 1;
1288                                 return;
1289                         }
1290                 }
1291                 /* Consume printed characters from the buffer. */
1292                 buffer_consume(&stderr_buffer, len);
1293                 stderr_bytes += len;
1294         }
1295 }
1296
1297 /*
1298  * Get packets from the connection input buffer, and process them as long as
1299  * there are packets available.
1300  *
1301  * Any unknown packets received during the actual
1302  * session cause the session to terminate.  This is
1303  * intended to make debugging easier since no
1304  * confirmations are sent.  Any compatible protocol
1305  * extensions must be negotiated during the
1306  * preparatory phase.
1307  */
1308
1309 static void
1310 client_process_buffered_input_packets(void)
1311 {
1312         dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL);
1313 }
1314
1315 /* scan buf[] for '~' before sending data to the peer */
1316
1317 static int
1318 simple_escape_filter(Channel *c, char *buf, int len)
1319 {
1320         /* XXX we assume c->extended is writeable */
1321         return process_escapes(&c->input, &c->output, &c->extended, buf, len);
1322 }
1323
1324 static void
1325 client_channel_closed(int id, void *arg)
1326 {
1327         channel_cancel_cleanup(id);
1328         session_closed = 1;
1329         leave_raw_mode();
1330 }
1331
1332 /*
1333  * Implements the interactive session with the server.  This is called after
1334  * the user has been authenticated, and a command has been started on the
1335  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1336  * used as an escape character for terminating or suspending the session.
1337  */
1338
1339 int
1340 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1341 {
1342         fd_set *readset = NULL, *writeset = NULL;
1343         double start_time, total_time;
1344         int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1345         u_int nalloc = 0;
1346         char buf[100];
1347
1348         debug("Entering interactive session.");
1349
1350         start_time = get_current_time();
1351
1352         /* Initialize variables. */
1353         escape_pending = 0;
1354         last_was_cr = 1;
1355         exit_status = -1;
1356         stdin_eof = 0;
1357         buffer_high = 64 * 1024;
1358         connection_in = packet_get_connection_in();
1359         connection_out = packet_get_connection_out();
1360         max_fd = MAX(connection_in, connection_out);
1361         if (control_fd != -1)
1362                 max_fd = MAX(max_fd, control_fd);
1363
1364         if (!compat20) {
1365                 /* enable nonblocking unless tty */
1366                 if (!isatty(fileno(stdin)))
1367                         set_nonblock(fileno(stdin));
1368                 if (!isatty(fileno(stdout)))
1369                         set_nonblock(fileno(stdout));
1370                 if (!isatty(fileno(stderr)))
1371                         set_nonblock(fileno(stderr));
1372                 max_fd = MAX(max_fd, fileno(stdin));
1373                 max_fd = MAX(max_fd, fileno(stdout));
1374                 max_fd = MAX(max_fd, fileno(stderr));
1375         }
1376         stdin_bytes = 0;
1377         stdout_bytes = 0;
1378         stderr_bytes = 0;
1379         quit_pending = 0;
1380         escape_char = escape_char_arg;
1381
1382         /* Initialize buffers. */
1383         buffer_init(&stdin_buffer);
1384         buffer_init(&stdout_buffer);
1385         buffer_init(&stderr_buffer);
1386
1387         client_init_dispatch();
1388
1389         /*
1390          * Set signal handlers, (e.g. to restore non-blocking mode)
1391          * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1392          */
1393         if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1394                 signal(SIGHUP, signal_handler);
1395         if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1396                 signal(SIGINT, signal_handler);
1397         if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1398                 signal(SIGQUIT, signal_handler);
1399         if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1400                 signal(SIGTERM, signal_handler);
1401         signal(SIGWINCH, window_change_handler);
1402
1403         if (have_pty)
1404                 enter_raw_mode();
1405
1406         if (compat20) {
1407                 session_ident = ssh2_chan_id;
1408                 if (escape_char != SSH_ESCAPECHAR_NONE)
1409                         channel_register_filter(session_ident,
1410                             simple_escape_filter, NULL);
1411                 if (session_ident != -1)
1412                         channel_register_cleanup(session_ident,
1413                             client_channel_closed, 0);
1414         } else {
1415                 /* Check if we should immediately send eof on stdin. */
1416                 client_check_initial_eof_on_stdin();
1417         }
1418
1419         /* Main loop of the client for the interactive session mode. */
1420         while (!quit_pending) {
1421
1422                 /* Process buffered packets sent by the server. */
1423                 client_process_buffered_input_packets();
1424
1425                 if (compat20 && session_closed && !channel_still_open())
1426                         break;
1427
1428                 rekeying = (xxx_kex != NULL && !xxx_kex->done);
1429
1430                 if (rekeying) {
1431                         debug("rekeying in progress");
1432                 } else {
1433                         /*
1434                          * Make packets of buffered stdin data, and buffer
1435                          * them for sending to the server.
1436                          */
1437                         if (!compat20)
1438                                 client_make_packets_from_stdin_data();
1439
1440                         /*
1441                          * Make packets from buffered channel data, and
1442                          * enqueue them for sending to the server.
1443                          */
1444                         if (packet_not_very_much_data_to_write())
1445                                 channel_output_poll();
1446
1447                         /*
1448                          * Check if the window size has changed, and buffer a
1449                          * message about it to the server if so.
1450                          */
1451                         client_check_window_change();
1452
1453                         if (quit_pending)
1454                                 break;
1455                 }
1456                 /*
1457                  * Wait until we have something to do (something becomes
1458                  * available on one of the descriptors).
1459                  */
1460                 max_fd2 = max_fd;
1461                 client_wait_until_can_do_something(&readset, &writeset,
1462                     &max_fd2, &nalloc, rekeying);
1463
1464                 if (quit_pending)
1465                         break;
1466
1467                 /* Do channel operations unless rekeying in progress. */
1468                 if (!rekeying) {
1469                         channel_after_select(readset, writeset);
1470                         if (need_rekeying || packet_need_rekeying()) {
1471                                 debug("need rekeying");
1472                                 xxx_kex->done = 0;
1473                                 kex_send_kexinit(xxx_kex);
1474                                 need_rekeying = 0;
1475                         }
1476                 }
1477
1478                 /* Buffer input from the connection.  */
1479                 client_process_net_input(readset);
1480
1481                 /* Accept control connections.  */
1482                 client_process_control(readset);
1483
1484                 if (quit_pending)
1485                         break;
1486
1487                 if (!compat20) {
1488                         /* Buffer data from stdin */
1489                         client_process_input(readset);
1490                         /*
1491                          * Process output to stdout and stderr.  Output to
1492                          * the connection is processed elsewhere (above).
1493                          */
1494                         client_process_output(writeset);
1495                 }
1496
1497                 /* Send as much buffered packet data as possible to the sender. */
1498                 if (FD_ISSET(connection_out, writeset))
1499                         packet_write_poll();
1500         }
1501         if (readset)
1502                 xfree(readset);
1503         if (writeset)
1504                 xfree(writeset);
1505
1506         /* Terminate the session. */
1507
1508         /* Stop watching for window change. */
1509         signal(SIGWINCH, SIG_DFL);
1510
1511         channel_free_all();
1512
1513         if (have_pty)
1514                 leave_raw_mode();
1515
1516         /* restore blocking io */
1517         if (!isatty(fileno(stdin)))
1518                 unset_nonblock(fileno(stdin));
1519         if (!isatty(fileno(stdout)))
1520                 unset_nonblock(fileno(stdout));
1521         if (!isatty(fileno(stderr)))
1522                 unset_nonblock(fileno(stderr));
1523
1524         /*
1525          * If there was no shell or command requested, there will be no remote
1526          * exit status to be returned.  In that case, clear error code if the
1527          * connection was deliberately terminated at this end.
1528          */
1529         if (no_shell_flag && received_signal == SIGTERM) {
1530                 received_signal = 0;
1531                 exit_status = 0;
1532         }
1533
1534         if (received_signal)
1535                 fatal("Killed by signal %d.", (int) received_signal);
1536
1537         /*
1538          * In interactive mode (with pseudo tty) display a message indicating
1539          * that the connection has been closed.
1540          */
1541         if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1542                 snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
1543                 buffer_append(&stderr_buffer, buf, strlen(buf));
1544         }
1545
1546         /* Output any buffered data for stdout. */
1547         while (buffer_len(&stdout_buffer) > 0) {
1548                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1549                     buffer_len(&stdout_buffer));
1550                 if (len <= 0) {
1551                         error("Write failed flushing stdout buffer.");
1552                         break;
1553                 }
1554                 buffer_consume(&stdout_buffer, len);
1555                 stdout_bytes += len;
1556         }
1557
1558         /* Output any buffered data for stderr. */
1559         while (buffer_len(&stderr_buffer) > 0) {
1560                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1561                     buffer_len(&stderr_buffer));
1562                 if (len <= 0) {
1563                         error("Write failed flushing stderr buffer.");
1564                         break;
1565                 }
1566                 buffer_consume(&stderr_buffer, len);
1567                 stderr_bytes += len;
1568         }
1569
1570         /* Clear and free any buffers. */
1571         memset(buf, 0, sizeof(buf));
1572         buffer_free(&stdin_buffer);
1573         buffer_free(&stdout_buffer);
1574         buffer_free(&stderr_buffer);
1575
1576         /* Report bytes transferred, and transfer rates. */
1577         total_time = get_current_time() - start_time;
1578         debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
1579             stdin_bytes, stdout_bytes, stderr_bytes, total_time);
1580         if (total_time > 0)
1581                 debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
1582                     stdin_bytes / total_time, stdout_bytes / total_time,
1583                     stderr_bytes / total_time);
1584
1585         /* Return the exit status of the program. */
1586         debug("Exit status %d", exit_status);
1587         return exit_status;
1588 }
1589
1590 /*********/
1591
1592 static void
1593 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1594 {
1595         u_int data_len;
1596         char *data = packet_get_string(&data_len);
1597         packet_check_eom();
1598         buffer_append(&stdout_buffer, data, data_len);
1599         memset(data, 0, data_len);
1600         xfree(data);
1601 }
1602 static void
1603 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1604 {
1605         u_int data_len;
1606         char *data = packet_get_string(&data_len);
1607         packet_check_eom();
1608         buffer_append(&stderr_buffer, data, data_len);
1609         memset(data, 0, data_len);
1610         xfree(data);
1611 }
1612 static void
1613 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1614 {
1615         exit_status = packet_get_int();
1616         packet_check_eom();
1617         /* Acknowledge the exit. */
1618         packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1619         packet_send();
1620         /*
1621          * Must wait for packet to be sent since we are
1622          * exiting the loop.
1623          */
1624         packet_write_wait();
1625         /* Flag that we want to exit. */
1626         quit_pending = 1;
1627 }
1628 static void
1629 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1630 {
1631         Channel *c = NULL;
1632         int remote_id, sock;
1633
1634         /* Read the remote channel number from the message. */
1635         remote_id = packet_get_int();
1636         packet_check_eom();
1637
1638         /*
1639          * Get a connection to the local authentication agent (this may again
1640          * get forwarded).
1641          */
1642         sock = ssh_get_authentication_socket();
1643
1644         /*
1645          * If we could not connect the agent, send an error message back to
1646          * the server. This should never happen unless the agent dies,
1647          * because authentication forwarding is only enabled if we have an
1648          * agent.
1649          */
1650         if (sock >= 0) {
1651                 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1652                     -1, 0, 0, 0, "authentication agent connection", 1);
1653                 c->remote_id = remote_id;
1654                 c->force_drain = 1;
1655         }
1656         if (c == NULL) {
1657                 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1658                 packet_put_int(remote_id);
1659         } else {
1660                 /* Send a confirmation to the remote host. */
1661                 debug("Forwarding authentication connection.");
1662                 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1663                 packet_put_int(remote_id);
1664                 packet_put_int(c->self);
1665         }
1666         packet_send();
1667 }
1668
1669 static Channel *
1670 client_request_forwarded_tcpip(const char *request_type, int rchan)
1671 {
1672         Channel *c = NULL;
1673         char *listen_address, *originator_address;
1674         int listen_port, originator_port;
1675         int sock;
1676
1677         /* Get rest of the packet */
1678         listen_address = packet_get_string(NULL);
1679         listen_port = packet_get_int();
1680         originator_address = packet_get_string(NULL);
1681         originator_port = packet_get_int();
1682         packet_check_eom();
1683
1684         debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1685             listen_address, listen_port, originator_address, originator_port);
1686
1687         sock = channel_connect_by_listen_address(listen_port);
1688         if (sock < 0) {
1689                 xfree(originator_address);
1690                 xfree(listen_address);
1691                 return NULL;
1692         }
1693         c = channel_new("forwarded-tcpip",
1694             SSH_CHANNEL_CONNECTING, sock, sock, -1,
1695             CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1696             originator_address, 1);
1697         xfree(originator_address);
1698         xfree(listen_address);
1699         return c;
1700 }
1701
1702 static Channel *
1703 client_request_x11(const char *request_type, int rchan)
1704 {
1705         Channel *c = NULL;
1706         char *originator;
1707         int originator_port;
1708         int sock;
1709
1710         if (!options.forward_x11) {
1711                 error("Warning: ssh server tried X11 forwarding.");
1712                 error("Warning: this is probably a break-in attempt by a malicious server.");
1713                 return NULL;
1714         }
1715         originator = packet_get_string(NULL);
1716         if (datafellows & SSH_BUG_X11FWD) {
1717                 debug2("buggy server: x11 request w/o originator_port");
1718                 originator_port = 0;
1719         } else {
1720                 originator_port = packet_get_int();
1721         }
1722         packet_check_eom();
1723         /* XXX check permission */
1724         debug("client_request_x11: request from %s %d", originator,
1725             originator_port);
1726         xfree(originator);
1727         sock = x11_connect_display();
1728         if (sock < 0)
1729                 return NULL;
1730         c = channel_new("x11",
1731             SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1732             CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1733         c->force_drain = 1;
1734         return c;
1735 }
1736
1737 static Channel *
1738 client_request_agent(const char *request_type, int rchan)
1739 {
1740         Channel *c = NULL;
1741         int sock;
1742
1743         if (!options.forward_agent) {
1744                 error("Warning: ssh server tried agent forwarding.");
1745                 error("Warning: this is probably a break-in attempt by a malicious server.");
1746                 return NULL;
1747         }
1748         sock =  ssh_get_authentication_socket();
1749         if (sock < 0)
1750                 return NULL;
1751         c = channel_new("authentication agent connection",
1752             SSH_CHANNEL_OPEN, sock, sock, -1,
1753             CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1754             "authentication agent connection", 1);
1755         c->force_drain = 1;
1756         return c;
1757 }
1758
1759 /* XXXX move to generic input handler */
1760 static void
1761 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1762 {
1763         Channel *c = NULL;
1764         char *ctype;
1765         int rchan;
1766         u_int rmaxpack, rwindow, len;
1767
1768         ctype = packet_get_string(&len);
1769         rchan = packet_get_int();
1770         rwindow = packet_get_int();
1771         rmaxpack = packet_get_int();
1772
1773         debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1774             ctype, rchan, rwindow, rmaxpack);
1775
1776         if (strcmp(ctype, "forwarded-tcpip") == 0) {
1777                 c = client_request_forwarded_tcpip(ctype, rchan);
1778         } else if (strcmp(ctype, "x11") == 0) {
1779                 c = client_request_x11(ctype, rchan);
1780         } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1781                 c = client_request_agent(ctype, rchan);
1782         }
1783 /* XXX duplicate : */
1784         if (c != NULL) {
1785                 debug("confirm %s", ctype);
1786                 c->remote_id = rchan;
1787                 c->remote_window = rwindow;
1788                 c->remote_maxpacket = rmaxpack;
1789                 if (c->type != SSH_CHANNEL_CONNECTING) {
1790                         packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1791                         packet_put_int(c->remote_id);
1792                         packet_put_int(c->self);
1793                         packet_put_int(c->local_window);
1794                         packet_put_int(c->local_maxpacket);
1795                         packet_send();
1796                 }
1797         } else {
1798                 debug("failure %s", ctype);
1799                 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1800                 packet_put_int(rchan);
1801                 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1802                 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1803                         packet_put_cstring("open failed");
1804                         packet_put_cstring("");
1805                 }
1806                 packet_send();
1807         }
1808         xfree(ctype);
1809 }
1810 static void
1811 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1812 {
1813         Channel *c = NULL;
1814         int exitval, id, reply, success = 0;
1815         char *rtype;
1816
1817         id = packet_get_int();
1818         rtype = packet_get_string(NULL);
1819         reply = packet_get_char();
1820
1821         debug("client_input_channel_req: channel %d rtype %s reply %d",
1822             id, rtype, reply);
1823
1824         if (id == -1) {
1825                 error("client_input_channel_req: request for channel -1");
1826         } else if ((c = channel_lookup(id)) == NULL) {
1827                 error("client_input_channel_req: channel %d: unknown channel", id);
1828         } else if (strcmp(rtype, "exit-status") == 0) {
1829                 exitval = packet_get_int();
1830                 if (id == session_ident) {
1831                         success = 1;
1832                         exit_status = exitval;
1833                 } else if (c->ctl_fd == -1) {
1834                         error("client_input_channel_req: unexpected channel %d",
1835                             session_ident);
1836                 } else {
1837                         atomicio(vwrite, c->ctl_fd, &exitval, sizeof(exitval));
1838                         success = 1;
1839                 }
1840                 packet_check_eom();
1841         }
1842         if (reply) {
1843                 packet_start(success ?
1844                     SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1845                 packet_put_int(id);
1846                 packet_send();
1847         }
1848         xfree(rtype);
1849 }
1850 static void
1851 client_input_global_request(int type, u_int32_t seq, void *ctxt)
1852 {
1853         char *rtype;
1854         int want_reply;
1855         int success = 0;
1856
1857         rtype = packet_get_string(NULL);
1858         want_reply = packet_get_char();
1859         debug("client_input_global_request: rtype %s want_reply %d",
1860             rtype, want_reply);
1861         if (want_reply) {
1862                 packet_start(success ?
1863                     SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1864                 packet_send();
1865                 packet_write_wait();
1866         }
1867         xfree(rtype);
1868 }
1869
1870 void
1871 client_session2_setup(int id, int want_tty, int want_subsystem,
1872     const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env,
1873     dispatch_fn *subsys_repl)
1874 {
1875         int len;
1876         Channel *c = NULL;
1877
1878         debug2("%s: id %d", __func__, id);
1879
1880         if ((c = channel_lookup(id)) == NULL)
1881                 fatal("client_session2_setup: channel %d: unknown channel", id);
1882
1883         if (want_tty) {
1884                 struct winsize ws;
1885                 struct termios tio;
1886
1887                 /* Store window size in the packet. */
1888                 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
1889                         memset(&ws, 0, sizeof(ws));
1890
1891                 channel_request_start(id, "pty-req", 0);
1892                 packet_put_cstring(term != NULL ? term : "");
1893                 packet_put_int((u_int)ws.ws_col);
1894                 packet_put_int((u_int)ws.ws_row);
1895                 packet_put_int((u_int)ws.ws_xpixel);
1896                 packet_put_int((u_int)ws.ws_ypixel);
1897                 tio = get_saved_tio();
1898                 tty_make_modes(-1, tiop != NULL ? tiop : &tio);
1899                 packet_send();
1900                 /* XXX wait for reply */
1901                 c->client_tty = 1;
1902         }
1903
1904         /* Transfer any environment variables from client to server */
1905         if (options.num_send_env != 0 && env != NULL) {
1906                 int i, j, matched;
1907                 char *name, *val;
1908
1909                 debug("Sending environment.");
1910                 for (i = 0; env[i] != NULL; i++) {
1911                         /* Split */
1912                         name = xstrdup(env[i]);
1913                         if ((val = strchr(name, '=')) == NULL) {
1914                                 xfree(name);
1915                                 continue;
1916                         }
1917                         *val++ = '\0';
1918
1919                         matched = 0;
1920                         for (j = 0; j < options.num_send_env; j++) {
1921                                 if (match_pattern(name, options.send_env[j])) {
1922                                         matched = 1;
1923                                         break;
1924                                 }
1925                         }
1926                         if (!matched) {
1927                                 debug3("Ignored env %s", name);
1928                                 xfree(name);
1929                                 continue;
1930                         }
1931
1932                         debug("Sending env %s = %s", name, val);
1933                         channel_request_start(id, "env", 0);
1934                         packet_put_cstring(name);
1935                         packet_put_cstring(val);
1936                         packet_send();
1937                         xfree(name);
1938                 }
1939         }
1940
1941         len = buffer_len(cmd);
1942         if (len > 0) {
1943                 if (len > 900)
1944                         len = 900;
1945                 if (want_subsystem) {
1946                         debug("Sending subsystem: %.*s", len, (u_char*)buffer_ptr(cmd));
1947                         channel_request_start(id, "subsystem", subsys_repl != NULL);
1948                         if (subsys_repl != NULL) {
1949                                 /* register callback for reply */
1950                                 /* XXX we assume that client_loop has already been called */
1951                                 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, subsys_repl);
1952                                 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, subsys_repl);
1953                         }
1954                 } else {
1955                         debug("Sending command: %.*s", len, (u_char*)buffer_ptr(cmd));
1956                         channel_request_start(id, "exec", 0);
1957                 }
1958                 packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
1959                 packet_send();
1960         } else {
1961                 channel_request_start(id, "shell", 0);
1962                 packet_send();
1963         }
1964 }
1965
1966 static void
1967 client_init_dispatch_20(void)
1968 {
1969         dispatch_init(&dispatch_protocol_error);
1970
1971         dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1972         dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1973         dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1974         dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1975         dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1976         dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1977         dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1978         dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1979         dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1980         dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1981
1982         /* rekeying */
1983         dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1984
1985         /* global request reply messages */
1986         dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
1987         dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1988 }
1989 static void
1990 client_init_dispatch_13(void)
1991 {
1992         dispatch_init(NULL);
1993         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1994         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1995         dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1996         dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1997         dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1998         dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1999         dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2000         dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2001         dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
2002
2003         dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
2004             &client_input_agent_open : &deny_input_open);
2005         dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2006             &x11_input_open : &deny_input_open);
2007 }
2008 static void
2009 client_init_dispatch_15(void)
2010 {
2011         client_init_dispatch_13();
2012         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2013         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2014 }
2015 static void
2016 client_init_dispatch(void)
2017 {
2018         if (compat20)
2019                 client_init_dispatch_20();
2020         else if (compat13)
2021                 client_init_dispatch_13();
2022         else
2023                 client_init_dispatch_15();
2024 }
2025
2026 /* client specific fatal cleanup */
2027 void
2028 cleanup_exit(int i)
2029 {
2030         leave_raw_mode();
2031         leave_non_blocking();
2032         if (options.control_path != NULL && control_fd != -1)
2033                 unlink(options.control_path);
2034         _exit(i);
2035 }