clientloop.c

   1 /* $OpenBSD: clientloop.c,v 1.197 2008/06/12 04:17:47 djm 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 #include <sys/ioctl.h>
  66 #include <sys/param.h>
  67 #ifdef HAVE_SYS_STAT_H
  68 # include <sys/stat.h>
  69 #endif
  70 #ifdef HAVE_SYS_TIME_H
  71 # include <sys/time.h>
  72 #endif
  73 #include <sys/socket.h>
  74
  75 #include <ctype.h>
  76 #include <errno.h>
  77 #ifdef HAVE_PATHS_H
  78 #include <paths.h>
  79 #endif
  80 #include <signal.h>
  81 #include <stdarg.h>
  82 #include <stdio.h>
  83 #include <stdlib.h>
  84 #include <string.h>
  85 #include <termios.h>
  86 #include <pwd.h>
  87 #include <unistd.h>
  88
  89 #include "openbsd-compat/sys-queue.h"
  90 #include "xmalloc.h"
  91 #include "ssh.h"
  92 #include "ssh1.h"
  93 #include "ssh2.h"
  94 #include "packet.h"
  95 #include "buffer.h"
  96 #include "compat.h"
  97 #include "channels.h"
  98 #include "dispatch.h"
  99 #include "key.h"
 100 #include "cipher.h"
 101 #include "kex.h"
 102 #include "log.h"
 103 #include "readconf.h"
 104 #include "clientloop.h"
 105 #include "sshconnect.h"
 106 #include "authfd.h"
 107 #include "atomicio.h"
 108 #include "sshpty.h"
 109 #include "misc.h"
 110 #include "monitor_fdpass.h"
 111 #include "match.h"
 112 #include "msg.h"
 113
 114 /* import options */
 115 extern Options options;
 116
 117 /* Flag indicating that stdin should be redirected from /dev/null. */
 118 extern int stdin_null_flag;
 119
 120 /* Flag indicating that no shell has been requested */
 121 extern int no_shell_flag;
 122
 123 /* Control socket */
 124 extern int muxserver_sock;
 125
 126 /*
 127  * Name of the host we are connecting to.  This is the name given on the
 128  * command line, or the HostName specified for the user-supplied name in a
 129  * configuration file.
 130  */
 131 extern char *host;
 132
 133 /*
 134  * Flag to indicate that we have received a window change signal which has
 135  * not yet been processed.  This will cause a message indicating the new
 136  * window size to be sent to the server a little later.  This is volatile
 137  * because this is updated in a signal handler.
 138  */
 139 static volatile sig_atomic_t received_window_change_signal = 0;
 140 static volatile sig_atomic_t received_signal = 0;
 141
 142 /* Flag indicating whether the user's terminal is in non-blocking mode. */
 143 static int in_non_blocking_mode = 0;
 144
 145 /* Common data for the client loop code. */
 146 static volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
 147 static int escape_char1;        /* Escape character. (proto1 only) */
 148 static int escape_pending1;     /* Last character was an escape (proto1 only) */
 149 static int last_was_cr;         /* Last character was a newline. */
 150 static int exit_status;         /* Used to store the command exit status. */
 151 static int stdin_eof;           /* EOF has been encountered on stderr. */
 152 static Buffer stdin_buffer;     /* Buffer for stdin data. */
 153 static Buffer stdout_buffer;    /* Buffer for stdout data. */
 154 static Buffer stderr_buffer;    /* Buffer for stderr data. */
 155 static u_long stdin_bytes, stdout_bytes, stderr_bytes;
 156 static u_int buffer_high;/* Soft max buffer size. */
 157 static int connection_in;       /* Connection to server (input). */
 158 static int connection_out;      /* Connection to server (output). */
 159 static int need_rekeying;       /* Set to non-zero if rekeying is requested. */
 160 static int session_closed = 0;  /* In SSH2: login session closed. */
 161
 162 static void client_init_dispatch(void);
 163 int     session_ident = -1;
 164
 165 /* Track escape per proto2 channel */
 166 struct escape_filter_ctx {
 167         int escape_pending;
 168         int escape_char;
 169 };
 170
 171 /* Context for channel confirmation replies */
 172 struct channel_reply_ctx {
 173         const char *request_type;
 174         int id, do_close;
 175 };
 176
 177 /* Global request success/failure callbacks */
 178 struct global_confirm {
 179         TAILQ_ENTRY(global_confirm) entry;
 180         global_confirm_cb *cb;
 181         void *ctx;
 182         int ref_count;
 183 };
 184 TAILQ_HEAD(global_confirms, global_confirm);
 185 static struct global_confirms global_confirms =
 186     TAILQ_HEAD_INITIALIZER(global_confirms);
 187
 188 /*XXX*/
 189 extern Kex *xxx_kex;
 190
 191 void ssh_process_session2_setup(int, int, int, Buffer *);
 192
 193 /* Restores stdin to blocking mode. */
 194
 195 static void
 196 leave_non_blocking(void)
 197 {
 198         if (in_non_blocking_mode) {
 199                 unset_nonblock(fileno(stdin));
 200                 in_non_blocking_mode = 0;
 201         }
 202 }
 203
 204 /* Puts stdin terminal in non-blocking mode. */
 205
 206 static void
 207 enter_non_blocking(void)
 208 {
 209         in_non_blocking_mode = 1;
 210         set_nonblock(fileno(stdin));
 211 }
 212
 213 /*
 214  * Signal handler for the window change signal (SIGWINCH).  This just sets a
 215  * flag indicating that the window has changed.
 216  */
 217 /*ARGSUSED */
 218 static void
 219 window_change_handler(int sig)
 220 {
 221         received_window_change_signal = 1;
 222         signal(SIGWINCH, window_change_handler);
 223 }
 224
 225 /*
 226  * Signal handler for signals that cause the program to terminate.  These
 227  * signals must be trapped to restore terminal modes.
 228  */
 229 /*ARGSUSED */
 230 static void
 231 signal_handler(int sig)
 232 {
 233         received_signal = sig;
 234         quit_pending = 1;
 235 }
 236
 237 /*
 238  * Returns current time in seconds from Jan 1, 1970 with the maximum
 239  * available resolution.
 240  */
 241
 242 static double
 243 get_current_time(void)
 244 {
 245         struct timeval tv;
 246         gettimeofday(&tv, NULL);
 247         return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
 248 }
 249
 250 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
 251 void
 252 client_x11_get_proto(const char *display, const char *xauth_path,
 253     u_int trusted, char **_proto, char **_data)
 254 {
 255         char cmd[1024];
 256         char line[512];
 257         char xdisplay[512];
 258         static char proto[512], data[512];
 259         FILE *f;
 260         int got_data = 0, generated = 0, do_unlink = 0, i;
 261         char *xauthdir, *xauthfile;
 262         struct stat st;
 263
 264         xauthdir = xauthfile = NULL;
 265         *_proto = proto;
 266         *_data = data;
 267         proto[0] = data[0] = '\0';
 268
 269         if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
 270                 debug("No xauth program.");
 271         } else {
 272                 if (display == NULL) {
 273                         debug("x11_get_proto: DISPLAY not set");
 274                         return;
 275                 }
 276                 /*
 277                  * Handle FamilyLocal case where $DISPLAY does
 278                  * not match an authorization entry.  For this we
 279                  * just try "xauth list unix:displaynum.screennum".
 280                  * XXX: "localhost" match to determine FamilyLocal
 281                  *      is not perfect.
 282                  */
 283                 if (strncmp(display, "localhost:", 10) == 0) {
 284                         snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
 285                             display + 10);
 286                         display = xdisplay;
 287                 }
 288                 if (trusted == 0) {
 289                         xauthdir = xmalloc(MAXPATHLEN);
 290                         xauthfile = xmalloc(MAXPATHLEN);
 291                         strlcpy(xauthdir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
 292                         if (mkdtemp(xauthdir) != NULL) {
 293                                 do_unlink = 1;
 294                                 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
 295                                     xauthdir);
 296                                 snprintf(cmd, sizeof(cmd),
 297                                     "%s -f %s generate %s " SSH_X11_PROTO
 298                                     " untrusted timeout 1200 2>" _PATH_DEVNULL,
 299                                     xauth_path, xauthfile, display);
 300                                 debug2("x11_get_proto: %s", cmd);
 301                                 if (system(cmd) == 0)
 302                                         generated = 1;
 303                         }
 304                 }
 305
 306                 /*
 307                  * When in untrusted mode, we read the cookie only if it was
 308                  * successfully generated as an untrusted one in the step
 309                  * above.
 310                  */
 311                 if (trusted || generated) {
 312                         snprintf(cmd, sizeof(cmd),
 313                             "%s %s%s list %s 2>" _PATH_DEVNULL,
 314                             xauth_path,
 315                             generated ? "-f " : "" ,
 316                             generated ? xauthfile : "",
 317                             display);
 318                         debug2("x11_get_proto: %s", cmd);
 319                         f = popen(cmd, "r");
 320                         if (f && fgets(line, sizeof(line), f) &&
 321                             sscanf(line, "%*s %511s %511s", proto, data) == 2)
 322                                 got_data = 1;
 323                         if (f)
 324                                 pclose(f);
 325                 } else
 326                         error("Warning: untrusted X11 forwarding setup failed: "
 327                             "xauth key data not generated");
 328         }
 329
 330         if (do_unlink) {
 331                 unlink(xauthfile);
 332                 rmdir(xauthdir);
 333         }
 334         if (xauthdir)
 335                 xfree(xauthdir);
 336         if (xauthfile)
 337                 xfree(xauthfile);
 338
 339         /*
 340          * If we didn't get authentication data, just make up some
 341          * data.  The forwarding code will check the validity of the
 342          * response anyway, and substitute this data.  The X11
 343          * server, however, will ignore this fake data and use
 344          * whatever authentication mechanisms it was using otherwise
 345          * for the local connection.
 346          */
 347         if (!got_data) {
 348                 u_int32_t rnd = 0;
 349
 350                 logit("Warning: No xauth data; "
 351                     "using fake authentication data for X11 forwarding.");
 352                 strlcpy(proto, SSH_X11_PROTO, sizeof proto);
 353                 for (i = 0; i < 16; i++) {
 354                         if (i % 4 == 0)
 355                                 rnd = arc4random();
 356                         snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
 357                             rnd & 0xff);
 358                         rnd >>= 8;
 359                 }
 360         }
 361 }
 362
 363 /*
 364  * This is called when the interactive is entered.  This checks if there is
 365  * an EOF coming on stdin.  We must check this explicitly, as select() does
 366  * not appear to wake up when redirecting from /dev/null.
 367  */
 368
 369 static void
 370 client_check_initial_eof_on_stdin(void)
 371 {
 372         int len;
 373         char buf[1];
 374
 375         /*
 376          * If standard input is to be "redirected from /dev/null", we simply
 377          * mark that we have seen an EOF and send an EOF message to the
 378          * server. Otherwise, we try to read a single character; it appears
 379          * that for some files, such /dev/null, select() never wakes up for
 380          * read for this descriptor, which means that we never get EOF.  This
 381          * way we will get the EOF if stdin comes from /dev/null or similar.
 382          */
 383         if (stdin_null_flag) {
 384                 /* Fake EOF on stdin. */
 385                 debug("Sending eof.");
 386                 stdin_eof = 1;
 387                 packet_start(SSH_CMSG_EOF);
 388                 packet_send();
 389         } else {
 390                 enter_non_blocking();
 391
 392                 /* Check for immediate EOF on stdin. */
 393                 len = read(fileno(stdin), buf, 1);
 394                 if (len == 0) {
 395                         /*
 396                          * EOF.  Record that we have seen it and send
 397                          * EOF to server.
 398                          */
 399                         debug("Sending eof.");
 400                         stdin_eof = 1;
 401                         packet_start(SSH_CMSG_EOF);
 402                         packet_send();
 403                 } else if (len > 0) {
 404                         /*
 405                          * Got data.  We must store the data in the buffer,
 406                          * and also process it as an escape character if
 407                          * appropriate.
 408                          */
 409                         if ((u_char) buf[0] == escape_char1)
 410                                 escape_pending1 = 1;
 411                         else
 412                                 buffer_append(&stdin_buffer, buf, 1);
 413                 }
 414                 leave_non_blocking();
 415         }
 416 }
 417
 418
 419 /*
 420  * Make packets from buffered stdin data, and buffer them for sending to the
 421  * connection.
 422  */
 423
 424 static void
 425 client_make_packets_from_stdin_data(void)
 426 {
 427         u_int len;
 428
 429         /* Send buffered stdin data to the server. */
 430         while (buffer_len(&stdin_buffer) > 0 &&
 431             packet_not_very_much_data_to_write()) {
 432                 len = buffer_len(&stdin_buffer);
 433                 /* Keep the packets at reasonable size. */
 434                 if (len > packet_get_maxsize())
 435                         len = packet_get_maxsize();
 436                 packet_start(SSH_CMSG_STDIN_DATA);
 437                 packet_put_string(buffer_ptr(&stdin_buffer), len);
 438                 packet_send();
 439                 buffer_consume(&stdin_buffer, len);
 440                 stdin_bytes += len;
 441                 /* If we have a pending EOF, send it now. */
 442                 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
 443                         packet_start(SSH_CMSG_EOF);
 444                         packet_send();
 445                 }
 446         }
 447 }
 448
 449 /*
 450  * Checks if the client window has changed, and sends a packet about it to
 451  * the server if so.  The actual change is detected elsewhere (by a software
 452  * interrupt on Unix); this just checks the flag and sends a message if
 453  * appropriate.
 454  */
 455
 456 static void
 457 client_check_window_change(void)
 458 {
 459         struct winsize ws;
 460
 461         if (! received_window_change_signal)
 462                 return;
 463         /** XXX race */
 464         received_window_change_signal = 0;
 465
 466         debug2("client_check_window_change: changed");
 467
 468         if (compat20) {
 469                 channel_send_window_changes();
 470         } else {
 471                 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
 472                         return;
 473                 packet_start(SSH_CMSG_WINDOW_SIZE);
 474                 packet_put_int((u_int)ws.ws_row);
 475                 packet_put_int((u_int)ws.ws_col);
 476                 packet_put_int((u_int)ws.ws_xpixel);
 477                 packet_put_int((u_int)ws.ws_ypixel);
 478                 packet_send();
 479         }
 480 }
 481
 482 static void
 483 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
 484 {
 485         struct global_confirm *gc;
 486
 487         if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
 488                 return;
 489         if (gc->cb != NULL)
 490                 gc->cb(type, seq, gc->ctx);
 491         if (--gc->ref_count <= 0) {
 492                 TAILQ_REMOVE(&global_confirms, gc, entry);
 493                 bzero(gc, sizeof(*gc));
 494                 xfree(gc);
 495         }
 496
 497         keep_alive_timeouts = 0;
 498 }
 499
 500 static void
 501 server_alive_check(void)
 502 {
 503         if (++keep_alive_timeouts > options.server_alive_count_max) {
 504                 logit("Timeout, server not responding.");
 505                 cleanup_exit(255);
 506         }
 507         packet_start(SSH2_MSG_GLOBAL_REQUEST);
 508         packet_put_cstring("keepalive@openssh.com");
 509         packet_put_char(1);     /* boolean: want reply */
 510         packet_send();
 511         /* Insert an empty placeholder to maintain ordering */
 512         client_register_global_confirm(NULL, NULL);
 513 }
 514
 515 /*
 516  * Waits until the client can do something (some data becomes available on
 517  * one of the file descriptors).
 518  */
 519 static void
 520 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
 521     int *maxfdp, u_int *nallocp, int rekeying)
 522 {
 523         struct timeval tv, *tvp;
 524         int ret;
 525
 526         /* Add any selections by the channel mechanism. */
 527         channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
 528
 529         if (!compat20) {
 530                 /* Read from the connection, unless our buffers are full. */
 531                 if (buffer_len(&stdout_buffer) < buffer_high &&
 532                     buffer_len(&stderr_buffer) < buffer_high &&
 533                     channel_not_very_much_buffered_data())
 534                         FD_SET(connection_in, *readsetp);
 535                 /*
 536                  * Read from stdin, unless we have seen EOF or have very much
 537                  * buffered data to send to the server.
 538                  */
 539                 if (!stdin_eof && packet_not_very_much_data_to_write())
 540                         FD_SET(fileno(stdin), *readsetp);
 541
 542                 /* Select stdout/stderr if have data in buffer. */
 543                 if (buffer_len(&stdout_buffer) > 0)
 544                         FD_SET(fileno(stdout), *writesetp);
 545                 if (buffer_len(&stderr_buffer) > 0)
 546                         FD_SET(fileno(stderr), *writesetp);
 547         } else {
 548                 /* channel_prepare_select could have closed the last channel */
 549                 if (session_closed && !channel_still_open() &&
 550                     !packet_have_data_to_write()) {
 551                         /* clear mask since we did not call select() */
 552                         memset(*readsetp, 0, *nallocp);
 553                         memset(*writesetp, 0, *nallocp);
 554                         return;
 555                 } else {
 556                         FD_SET(connection_in, *readsetp);
 557                 }
 558         }
 559
 560         /* Select server connection if have data to write to the server. */
 561         if (packet_have_data_to_write())
 562                 FD_SET(connection_out, *writesetp);
 563
 564         if (muxserver_sock != -1)
 565                 FD_SET(muxserver_sock, *readsetp);
 566
 567         /*
 568          * Wait for something to happen.  This will suspend the process until
 569          * some selected descriptor can be read, written, or has some other
 570          * event pending.
 571          */
 572
 573         if (options.server_alive_interval == 0 || !compat20)
 574                 tvp = NULL;
 575         else {
 576                 tv.tv_sec = options.server_alive_interval;
 577                 tv.tv_usec = 0;
 578                 tvp = &tv;
 579         }
 580         ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
 581         if (ret < 0) {
 582                 char buf[100];
 583
 584                 /*
 585                  * We have to clear the select masks, because we return.
 586                  * We have to return, because the mainloop checks for the flags
 587                  * set by the signal handlers.
 588                  */
 589                 memset(*readsetp, 0, *nallocp);
 590                 memset(*writesetp, 0, *nallocp);
 591
 592                 if (errno == EINTR)
 593                         return;
 594                 /* Note: we might still have data in the buffers. */
 595                 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
 596                 buffer_append(&stderr_buffer, buf, strlen(buf));
 597                 quit_pending = 1;
 598         } else if (ret == 0)
 599                 server_alive_check();
 600 }
 601
 602 static void
 603 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
 604 {
 605         /* Flush stdout and stderr buffers. */
 606         if (buffer_len(bout) > 0)
 607                 atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
 608                     buffer_len(bout));
 609         if (buffer_len(berr) > 0)
 610                 atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
 611                     buffer_len(berr));
 612
 613         leave_raw_mode();
 614
 615         /*
 616          * Free (and clear) the buffer to reduce the amount of data that gets
 617          * written to swap.
 618          */
 619         buffer_free(bin);
 620         buffer_free(bout);
 621         buffer_free(berr);
 622
 623         /* Send the suspend signal to the program itself. */
 624         kill(getpid(), SIGTSTP);
 625
 626         /* Reset window sizes in case they have changed */
 627         received_window_change_signal = 1;
 628
 629         /* OK, we have been continued by the user. Reinitialize buffers. */
 630         buffer_init(bin);
 631         buffer_init(bout);
 632         buffer_init(berr);
 633
 634         enter_raw_mode();
 635 }
 636
 637 static void
 638 client_process_net_input(fd_set *readset)
 639 {
 640         int len;
 641         char buf[8192];
 642
 643         /*
 644          * Read input from the server, and add any such data to the buffer of
 645          * the packet subsystem.
 646          */
 647         if (FD_ISSET(connection_in, readset)) {
 648                 /* Read as much as possible. */
 649                 len = read(connection_in, buf, sizeof(buf));
 650                 if (len == 0) {
 651                         /*
 652                          * Received EOF.  The remote host has closed the
 653                          * connection.
 654                          */
 655                         snprintf(buf, sizeof buf,
 656                             "Connection to %.300s closed by remote host.\r\n",
 657                             host);
 658                         buffer_append(&stderr_buffer, buf, strlen(buf));
 659                         quit_pending = 1;
 660                         return;
 661                 }
 662                 /*
 663                  * There is a kernel bug on Solaris that causes select to
 664                  * sometimes wake up even though there is no data available.
 665                  */
 666                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
 667                         len = 0;
 668
 669                 if (len < 0) {
 670                         /*
 671                          * An error has encountered.  Perhaps there is a
 672                          * network problem.
 673                          */
 674                         snprintf(buf, sizeof buf,
 675                             "Read from remote host %.300s: %.100s\r\n",
 676                             host, strerror(errno));
 677                         buffer_append(&stderr_buffer, buf, strlen(buf));
 678                         quit_pending = 1;
 679                         return;
 680                 }
 681                 packet_process_incoming(buf, len);
 682         }
 683 }
 684
 685 static void
 686 client_status_confirm(int type, Channel *c, void *ctx)
 687 {
 688         struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
 689         char errmsg[256];
 690         int tochan;
 691
 692         /* XXX supress on mux _client_ quietmode */
 693         tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
 694             c->ctl_fd != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
 695
 696         if (type == SSH2_MSG_CHANNEL_SUCCESS) {
 697                 debug2("%s request accepted on channel %d",
 698                     cr->request_type, c->self);
 699         } else if (type == SSH2_MSG_CHANNEL_FAILURE) {
 700                 if (tochan) {
 701                         snprintf(errmsg, sizeof(errmsg),
 702                             "%s request failed\r\n", cr->request_type);
 703                 } else {
 704                         snprintf(errmsg, sizeof(errmsg),
 705                             "%s request failed on channel %d",
 706                             cr->request_type, c->self);
 707                 }
 708                 /* If error occurred on primary session channel, then exit */
 709                 if (cr->do_close && c->self == session_ident)
 710                         fatal("%s", errmsg);
 711                 /* If error occurred on mux client, append to their stderr */
 712                 if (tochan)
 713                         buffer_append(&c->extended, errmsg, strlen(errmsg));
 714                 else
 715                         error("%s", errmsg);
 716                 if (cr->do_close) {
 717                         chan_read_failed(c);
 718                         chan_write_failed(c);
 719                 }
 720         }
 721         xfree(cr);
 722 }
 723
 724 static void
 725 client_abandon_status_confirm(Channel *c, void *ctx)
 726 {
 727         xfree(ctx);
 728 }
 729
 730 static void
 731 client_expect_confirm(int id, const char *request, int do_close)
 732 {
 733         struct channel_reply_ctx *cr = xmalloc(sizeof(*cr));
 734
 735         cr->request_type = request;
 736         cr->do_close = do_close;
 737
 738         channel_register_status_confirm(id, client_status_confirm,
 739             client_abandon_status_confirm, cr);
 740 }
 741
 742 void
 743 client_register_global_confirm(global_confirm_cb *cb, void *ctx)
 744 {
 745         struct global_confirm *gc, *first_gc;
 746
 747         /* Coalesce identical callbacks */
 748         first_gc = TAILQ_FIRST(&global_confirms);
 749         if (first_gc && first_gc->cb == cb && first_gc->ctx == ctx) {
 750                 if (++first_gc->ref_count >= INT_MAX)
 751                         fatal("%s: first_gc->ref_count = %d",
 752                             __func__, first_gc->ref_count);
 753                 return;
 754         }
 755
 756         gc = xmalloc(sizeof(*gc));
 757         gc->cb = cb;
 758         gc->ctx = ctx;
 759         gc->ref_count = 1;
 760         TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
 761 }
 762
 763 static void
 764 process_cmdline(void)
 765 {
 766         void (*handler)(int);
 767         char *s, *cmd, *cancel_host;
 768         int delete = 0;
 769         int local = 0;
 770         u_short cancel_port;
 771         Forward fwd;
 772
 773         bzero(&fwd, sizeof(fwd));
 774         fwd.listen_host = fwd.connect_host = NULL;
 775
 776         leave_raw_mode();
 777         handler = signal(SIGINT, SIG_IGN);
 778         cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
 779         if (s == NULL)
 780                 goto out;
 781         while (isspace(*s))
 782                 s++;
 783         if (*s == '-')
 784                 s++;    /* Skip cmdline '-', if any */
 785         if (*s == '\0')
 786                 goto out;
 787
 788         if (*s == 'h' || *s == 'H' || *s == '?') {
 789                 logit("Commands:");
 790                 logit("      -L[bind_address:]port:host:hostport    "
 791                     "Request local forward");
 792                 logit("      -R[bind_address:]port:host:hostport    "
 793                     "Request remote forward");
 794                 logit("      -KR[bind_address:]port                 "
 795                     "Cancel remote forward");
 796                 if (!options.permit_local_command)
 797                         goto out;
 798                 logit("      !args                                  "
 799                     "Execute local command");
 800                 goto out;
 801         }
 802
 803         if (*s == '!' && options.permit_local_command) {
 804                 s++;
 805                 ssh_local_cmd(s);
 806                 goto out;
 807         }
 808
 809         if (*s == 'K') {
 810                 delete = 1;
 811                 s++;
 812         }
 813         if (*s != 'L' && *s != 'R') {
 814                 logit("Invalid command.");
 815                 goto out;
 816         }
 817         if (*s == 'L')
 818                 local = 1;
 819         if (local && delete) {
 820                 logit("Not supported.");
 821                 goto out;
 822         }
 823         if ((!local || delete) && !compat20) {
 824                 logit("Not supported for SSH protocol version 1.");
 825                 goto out;
 826         }
 827
 828         while (isspace(*++s))
 829                 ;
 830
 831         if (delete) {
 832                 cancel_port = 0;
 833                 cancel_host = hpdelim(&s);      /* may be NULL */
 834                 if (s != NULL) {
 835                         cancel_port = a2port(s);
 836                         cancel_host = cleanhostname(cancel_host);
 837                 } else {
 838                         cancel_port = a2port(cancel_host);
 839                         cancel_host = NULL;
 840                 }
 841                 if (cancel_port == 0) {
 842                         logit("Bad forwarding close port");
 843                         goto out;
 844                 }
 845                 channel_request_rforward_cancel(cancel_host, cancel_port);
 846         } else {
 847                 if (!parse_forward(&fwd, s)) {
 848                         logit("Bad forwarding specification.");
 849                         goto out;
 850                 }
 851                 if (local) {
 852                         if (channel_setup_local_fwd_listener(fwd.listen_host,
 853                             fwd.listen_port, fwd.connect_host,
 854                             fwd.connect_port, options.gateway_ports) < 0) {
 855                                 logit("Port forwarding failed.");
 856                                 goto out;
 857                         }
 858                 } else {
 859                         if (channel_request_remote_forwarding(fwd.listen_host,
 860                             fwd.listen_port, fwd.connect_host,
 861                             fwd.connect_port) < 0) {
 862                                 logit("Port forwarding failed.");
 863                                 goto out;
 864                         }
 865                 }
 866
 867                 logit("Forwarding port.");
 868         }
 869
 870 out:
 871         signal(SIGINT, handler);
 872         enter_raw_mode();
 873         if (cmd)
 874                 xfree(cmd);
 875         if (fwd.listen_host != NULL)
 876                 xfree(fwd.listen_host);
 877         if (fwd.connect_host != NULL)
 878                 xfree(fwd.connect_host);
 879 }
 880
 881 /*
 882  * Process the characters one by one, call with c==NULL for proto1 case.
 883  */
 884 static int
 885 process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
 886     char *buf, int len)
 887 {
 888         char string[1024];
 889         pid_t pid;
 890         int bytes = 0;
 891         u_int i;
 892         u_char ch;
 893         char *s;
 894         int *escape_pendingp, escape_char;
 895         struct escape_filter_ctx *efc;
 896
 897         if (c == NULL) {
 898                 escape_pendingp = &escape_pending1;
 899                 escape_char = escape_char1;
 900         } else {
 901                 if (c->filter_ctx == NULL)
 902                         return 0;
 903                 efc = (struct escape_filter_ctx *)c->filter_ctx;
 904                 escape_pendingp = &efc->escape_pending;
 905                 escape_char = efc->escape_char;
 906         }
 907
 908         if (len <= 0)
 909                 return (0);
 910
 911         for (i = 0; i < (u_int)len; i++) {
 912                 /* Get one character at a time. */
 913                 ch = buf[i];
 914
 915                 if (*escape_pendingp) {
 916                         /* We have previously seen an escape character. */
 917                         /* Clear the flag now. */
 918                         *escape_pendingp = 0;
 919
 920                         /* Process the escaped character. */
 921                         switch (ch) {
 922                         case '.':
 923                                 /* Terminate the connection. */
 924                                 snprintf(string, sizeof string, "%c.\r\n",
 925                                     escape_char);
 926                                 buffer_append(berr, string, strlen(string));
 927
 928                                 if (c && c->ctl_fd != -1) {
 929                                         chan_read_failed(c);
 930                                         chan_write_failed(c);
 931                                         return 0;
 932                                 } else
 933                                         quit_pending = 1;
 934                                 return -1;
 935
 936                         case 'Z' - 64:
 937                                 /* XXX support this for mux clients */
 938                                 if (c && c->ctl_fd != -1) {
 939  noescape:
 940                                         snprintf(string, sizeof string,
 941                                             "%c%c escape not available to "
 942                                             "multiplexed sessions\r\n",
 943                                             escape_char, ch);
 944                                         buffer_append(berr, string,
 945                                             strlen(string));
 946                                         continue;
 947                                 }
 948                                 /* Suspend the program. Inform the user */
 949                                 snprintf(string, sizeof string,
 950                                     "%c^Z [suspend ssh]\r\n", escape_char);
 951                                 buffer_append(berr, string, strlen(string));
 952
 953                                 /* Restore terminal modes and suspend. */
 954                                 client_suspend_self(bin, bout, berr);
 955
 956                                 /* We have been continued. */
 957                                 continue;
 958
 959                         case 'B':
 960                                 if (compat20) {
 961                                         snprintf(string, sizeof string,
 962                                             "%cB\r\n", escape_char);
 963                                         buffer_append(berr, string,
 964                                             strlen(string));
 965                                         channel_request_start(session_ident,
 966                                             "break", 0);
 967                                         packet_put_int(1000);
 968                                         packet_send();
 969                                 }
 970                                 continue;
 971
 972                         case 'R':
 973                                 if (compat20) {
 974                                         if (datafellows & SSH_BUG_NOREKEY)
 975                                                 logit("Server does not "
 976                                                     "support re-keying");
 977                                         else
 978                                                 need_rekeying = 1;
 979                                 }
 980                                 continue;
 981
 982                         case '&':
 983                                 if (c && c->ctl_fd != -1)
 984                                         goto noescape;
 985                                 /*
 986                                  * Detach the program (continue to serve
 987                                  * connections, but put in background and no
 988                                  * more new connections).
 989                                  */
 990                                 /* Restore tty modes. */
 991                                 leave_raw_mode();
 992
 993                                 /* Stop listening for new connections. */
 994                                 channel_stop_listening();
 995
 996                                 snprintf(string, sizeof string,
 997                                     "%c& [backgrounded]\n", escape_char);
 998                                 buffer_append(berr, string, strlen(string));
 999
1000                                 /* Fork into background. */
1001                                 pid = fork();
1002                                 if (pid < 0) {
1003                                         error("fork: %.100s", strerror(errno));
1004                                         continue;
1005                                 }
1006                                 if (pid != 0) { /* This is the parent. */
1007                                         /* The parent just exits. */
1008                                         exit(0);
1009                                 }
1010                                 /* The child continues serving connections. */
1011                                 if (compat20) {
1012                                         buffer_append(bin, "\004", 1);
1013                                         /* fake EOF on stdin */
1014                                         return -1;
1015                                 } else if (!stdin_eof) {
1016                                         /*
1017                                          * Sending SSH_CMSG_EOF alone does not
1018                                          * always appear to be enough.  So we
1019                                          * try to send an EOF character first.
1020                                          */
1021                                         packet_start(SSH_CMSG_STDIN_DATA);
1022                                         packet_put_string("\004", 1);
1023                                         packet_send();
1024                                         /* Close stdin. */
1025                                         stdin_eof = 1;
1026                                         if (buffer_len(bin) == 0) {
1027                                                 packet_start(SSH_CMSG_EOF);
1028                                                 packet_send();
1029                                         }
1030                                 }
1031                                 continue;
1032
1033                         case '?':
1034                                 if (c && c->ctl_fd != -1) {
1035                                         snprintf(string, sizeof string,
1036 "%c?\r\n\
1037 Supported escape sequences:\r\n\
1038   %c.  - terminate session\r\n\
1039   %cB  - send a BREAK to the remote system\r\n\
1040   %cC  - open a command line\r\n\
1041   %cR  - Request rekey (SSH protocol 2 only)\r\n\
1042   %c#  - list forwarded connections\r\n\
1043   %c?  - this message\r\n\
1044   %c%c  - send the escape character by typing it twice\r\n\
1045 (Note that escapes are only recognized immediately after newline.)\r\n",
1046                                             escape_char, escape_char,
1047                                             escape_char, escape_char,
1048                                             escape_char, escape_char,
1049                                             escape_char, escape_char,
1050                                             escape_char);
1051                                 } else {
1052                                         snprintf(string, sizeof string,
1053 "%c?\r\n\
1054 Supported escape sequences:\r\n\
1055   %c.  - terminate connection (and any multiplexed sessions)\r\n\
1056   %cB  - send a BREAK to the remote system\r\n\
1057   %cC  - open a command line\r\n\
1058   %cR  - Request rekey (SSH protocol 2 only)\r\n\
1059   %c^Z - suspend ssh\r\n\
1060   %c#  - list forwarded connections\r\n\
1061   %c&  - background ssh (when waiting for connections to terminate)\r\n\
1062   %c?  - this message\r\n\
1063   %c%c  - send the escape character by typing it twice\r\n\
1064 (Note that escapes are only recognized immediately after newline.)\r\n",
1065                                             escape_char, escape_char,
1066                                             escape_char, escape_char,
1067                                             escape_char, escape_char,
1068                                             escape_char, escape_char,
1069                                             escape_char, escape_char,
1070                                             escape_char);
1071                                 }
1072                                 buffer_append(berr, string, strlen(string));
1073                                 continue;
1074
1075                         case '#':
1076                                 snprintf(string, sizeof string, "%c#\r\n",
1077                                     escape_char);
1078                                 buffer_append(berr, string, strlen(string));
1079                                 s = channel_open_message();
1080                                 buffer_append(berr, s, strlen(s));
1081                                 xfree(s);
1082                                 continue;
1083
1084                         case 'C':
1085                                 process_cmdline();
1086                                 continue;
1087
1088                         default:
1089                                 if (ch != escape_char) {
1090                                         buffer_put_char(bin, escape_char);
1091                                         bytes++;
1092                                 }
1093                                 /* Escaped characters fall through here */
1094                                 break;
1095                         }
1096                 } else {
1097                         /*
1098                          * The previous character was not an escape char.
1099                          * Check if this is an escape.
1100                          */
1101                         if (last_was_cr && ch == escape_char) {
1102                                 /*
1103                                  * It is. Set the flag and continue to
1104                                  * next character.
1105                                  */
1106                                 *escape_pendingp = 1;
1107                                 continue;
1108                         }
1109                 }
1110
1111                 /*
1112                  * Normal character.  Record whether it was a newline,
1113                  * and append it to the buffer.
1114                  */
1115                 last_was_cr = (ch == '\r' || ch == '\n');
1116                 buffer_put_char(bin, ch);
1117                 bytes++;
1118         }
1119         return bytes;
1120 }
1121
1122 static void
1123 client_process_input(fd_set *readset)
1124 {
1125         int len;
1126         char buf[8192];
1127
1128         /* Read input from stdin. */
1129         if (FD_ISSET(fileno(stdin), readset)) {
1130                 /* Read as much as possible. */
1131                 len = read(fileno(stdin), buf, sizeof(buf));
1132                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
1133                         return;         /* we'll try again later */
1134                 if (len <= 0) {
1135                         /*
1136                          * Received EOF or error.  They are treated
1137                          * similarly, except that an error message is printed
1138                          * if it was an error condition.
1139                          */
1140                         if (len < 0) {
1141                                 snprintf(buf, sizeof buf, "read: %.100s\r\n",
1142                                     strerror(errno));
1143                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1144                         }
1145                         /* Mark that we have seen EOF. */
1146                         stdin_eof = 1;
1147                         /*
1148                          * Send an EOF message to the server unless there is
1149                          * data in the buffer.  If there is data in the
1150                          * buffer, no message will be sent now.  Code
1151                          * elsewhere will send the EOF when the buffer
1152                          * becomes empty if stdin_eof is set.
1153                          */
1154                         if (buffer_len(&stdin_buffer) == 0) {
1155                                 packet_start(SSH_CMSG_EOF);
1156                                 packet_send();
1157                         }
1158                 } else if (escape_char1 == SSH_ESCAPECHAR_NONE) {
1159                         /*
1160                          * Normal successful read, and no escape character.
1161                          * Just append the data to buffer.
1162                          */
1163                         buffer_append(&stdin_buffer, buf, len);
1164                 } else {
1165                         /*
1166                          * Normal, successful read.  But we have an escape
1167                          * character and have to process the characters one
1168                          * by one.
1169                          */
1170                         if (process_escapes(NULL, &stdin_buffer,
1171                             &stdout_buffer, &stderr_buffer, buf, len) == -1)
1172                                 return;
1173                 }
1174         }
1175 }
1176
1177 static void
1178 client_process_output(fd_set *writeset)
1179 {
1180         int len;
1181         char buf[100];
1182
1183         /* Write buffered output to stdout. */
1184         if (FD_ISSET(fileno(stdout), writeset)) {
1185                 /* Write as much data as possible. */
1186                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1187                     buffer_len(&stdout_buffer));
1188                 if (len <= 0) {
1189                         if (errno == EINTR || errno == EAGAIN)
1190                                 len = 0;
1191                         else {
1192                                 /*
1193                                  * An error or EOF was encountered.  Put an
1194                                  * error message to stderr buffer.
1195                                  */
1196                                 snprintf(buf, sizeof buf,
1197                                     "write stdout: %.50s\r\n", strerror(errno));
1198                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1199                                 quit_pending = 1;
1200                                 return;
1201                         }
1202                 }
1203                 /* Consume printed data from the buffer. */
1204                 buffer_consume(&stdout_buffer, len);
1205                 stdout_bytes += len;
1206         }
1207         /* Write buffered output to stderr. */
1208         if (FD_ISSET(fileno(stderr), writeset)) {
1209                 /* Write as much data as possible. */
1210                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1211                     buffer_len(&stderr_buffer));
1212                 if (len <= 0) {
1213                         if (errno == EINTR || errno == EAGAIN)
1214                                 len = 0;
1215                         else {
1216                                 /*
1217                                  * EOF or error, but can't even print
1218                                  * error message.
1219                                  */
1220                                 quit_pending = 1;
1221                                 return;
1222                         }
1223                 }
1224                 /* Consume printed characters from the buffer. */
1225                 buffer_consume(&stderr_buffer, len);
1226                 stderr_bytes += len;
1227         }
1228 }
1229
1230 /*
1231  * Get packets from the connection input buffer, and process them as long as
1232  * there are packets available.
1233  *
1234  * Any unknown packets received during the actual
1235  * session cause the session to terminate.  This is
1236  * intended to make debugging easier since no
1237  * confirmations are sent.  Any compatible protocol
1238  * extensions must be negotiated during the
1239  * preparatory phase.
1240  */
1241
1242 static void
1243 client_process_buffered_input_packets(void)
1244 {
1245         dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
1246             compat20 ? xxx_kex : NULL);
1247 }
1248
1249 /* scan buf[] for '~' before sending data to the peer */
1250
1251 /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1252 void *
1253 client_new_escape_filter_ctx(int escape_char)
1254 {
1255         struct escape_filter_ctx *ret;
1256
1257         ret = xmalloc(sizeof(*ret));
1258         ret->escape_pending = 0;
1259         ret->escape_char = escape_char;
1260         return (void *)ret;
1261 }
1262
1263 int
1264 client_simple_escape_filter(Channel *c, char *buf, int len)
1265 {
1266         if (c->extended_usage != CHAN_EXTENDED_WRITE)
1267                 return 0;
1268
1269         return process_escapes(c, &c->input, &c->output, &c->extended,
1270             buf, len);
1271 }
1272
1273 static void
1274 client_channel_closed(int id, void *arg)
1275 {
1276         channel_cancel_cleanup(id);
1277         session_closed = 1;
1278         leave_raw_mode();
1279 }
1280
1281 /*
1282  * Implements the interactive session with the server.  This is called after
1283  * the user has been authenticated, and a command has been started on the
1284  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1285  * used as an escape character for terminating or suspending the session.
1286  */
1287
1288 int
1289 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1290 {
1291         fd_set *readset = NULL, *writeset = NULL;
1292         double start_time, total_time;
1293         int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1294         u_int nalloc = 0;
1295         char buf[100];
1296
1297         debug("Entering interactive session.");
1298
1299         start_time = get_current_time();
1300
1301         /* Initialize variables. */
1302         escape_pending1 = 0;
1303         last_was_cr = 1;
1304         exit_status = -1;
1305         stdin_eof = 0;
1306         buffer_high = 64 * 1024;
1307         connection_in = packet_get_connection_in();
1308         connection_out = packet_get_connection_out();
1309         max_fd = MAX(connection_in, connection_out);
1310         if (muxserver_sock != -1)
1311                 max_fd = MAX(max_fd, muxserver_sock);
1312
1313         if (!compat20) {
1314                 /* enable nonblocking unless tty */
1315                 if (!isatty(fileno(stdin)))
1316                         set_nonblock(fileno(stdin));
1317                 if (!isatty(fileno(stdout)))
1318                         set_nonblock(fileno(stdout));
1319                 if (!isatty(fileno(stderr)))
1320                         set_nonblock(fileno(stderr));
1321                 max_fd = MAX(max_fd, fileno(stdin));
1322                 max_fd = MAX(max_fd, fileno(stdout));
1323                 max_fd = MAX(max_fd, fileno(stderr));
1324         }
1325         stdin_bytes = 0;
1326         stdout_bytes = 0;
1327         stderr_bytes = 0;
1328         quit_pending = 0;
1329         escape_char1 = escape_char_arg;
1330
1331         /* Initialize buffers. */
1332         buffer_init(&stdin_buffer);
1333         buffer_init(&stdout_buffer);
1334         buffer_init(&stderr_buffer);
1335
1336         client_init_dispatch();
1337
1338         /*
1339          * Set signal handlers, (e.g. to restore non-blocking mode)
1340          * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1341          */
1342         if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1343                 signal(SIGHUP, signal_handler);
1344         if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1345                 signal(SIGINT, signal_handler);
1346         if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1347                 signal(SIGQUIT, signal_handler);
1348         if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1349                 signal(SIGTERM, signal_handler);
1350         signal(SIGWINCH, window_change_handler);
1351
1352         if (have_pty)
1353                 enter_raw_mode();
1354
1355         if (compat20) {
1356                 session_ident = ssh2_chan_id;
1357                 if (escape_char_arg != SSH_ESCAPECHAR_NONE)
1358                         channel_register_filter(session_ident,
1359                             client_simple_escape_filter, NULL,
1360                             client_new_escape_filter_ctx(escape_char_arg));
1361                 if (session_ident != -1)
1362                         channel_register_cleanup(session_ident,
1363                             client_channel_closed, 0);
1364         } else {
1365                 /* Check if we should immediately send eof on stdin. */
1366                 client_check_initial_eof_on_stdin();
1367         }
1368
1369         /* Main loop of the client for the interactive session mode. */
1370         while (!quit_pending) {
1371
1372                 /* Process buffered packets sent by the server. */
1373                 client_process_buffered_input_packets();
1374
1375                 if (compat20 && session_closed && !channel_still_open())
1376                         break;
1377
1378                 rekeying = (xxx_kex != NULL && !xxx_kex->done);
1379
1380                 if (rekeying) {
1381                         debug("rekeying in progress");
1382                 } else {
1383                         /*
1384                          * Make packets of buffered stdin data, and buffer
1385                          * them for sending to the server.
1386                          */
1387                         if (!compat20)
1388                                 client_make_packets_from_stdin_data();
1389
1390                         /*
1391                          * Make packets from buffered channel data, and
1392                          * enqueue them for sending to the server.
1393                          */
1394                         if (packet_not_very_much_data_to_write())
1395                                 channel_output_poll();
1396
1397                         /*
1398                          * Check if the window size has changed, and buffer a
1399                          * message about it to the server if so.
1400                          */
1401                         client_check_window_change();
1402
1403                         if (quit_pending)
1404                                 break;
1405                 }
1406                 /*
1407                  * Wait until we have something to do (something becomes
1408                  * available on one of the descriptors).
1409                  */
1410                 max_fd2 = max_fd;
1411                 client_wait_until_can_do_something(&readset, &writeset,
1412                     &max_fd2, &nalloc, rekeying);
1413
1414                 if (quit_pending)
1415                         break;
1416
1417                 /* Do channel operations unless rekeying in progress. */
1418                 if (!rekeying) {
1419                         channel_after_select(readset, writeset);
1420                         if (need_rekeying || packet_need_rekeying()) {
1421                                 debug("need rekeying");
1422                                 xxx_kex->done = 0;
1423                                 kex_send_kexinit(xxx_kex);
1424                                 need_rekeying = 0;
1425                         }
1426                 }
1427
1428                 /* Buffer input from the connection.  */
1429                 client_process_net_input(readset);
1430
1431                 /* Accept control connections.  */
1432                 if (muxserver_sock != -1 &&FD_ISSET(muxserver_sock, readset)) {
1433                         if (muxserver_accept_control())
1434                                 quit_pending = 1;
1435                 }
1436
1437                 if (quit_pending)
1438                         break;
1439
1440                 if (!compat20) {
1441                         /* Buffer data from stdin */
1442                         client_process_input(readset);
1443                         /*
1444                          * Process output to stdout and stderr.  Output to
1445                          * the connection is processed elsewhere (above).
1446                          */
1447                         client_process_output(writeset);
1448                 }
1449
1450                 /*
1451                  * Send as much buffered packet data as possible to the
1452                  * sender.
1453                  */
1454                 if (FD_ISSET(connection_out, writeset))
1455                         packet_write_poll();
1456         }
1457         if (readset)
1458                 xfree(readset);
1459         if (writeset)
1460                 xfree(writeset);
1461
1462         /* Terminate the session. */
1463
1464         /* Stop watching for window change. */
1465         signal(SIGWINCH, SIG_DFL);
1466
1467         channel_free_all();
1468
1469         if (have_pty)
1470                 leave_raw_mode();
1471
1472         /* restore blocking io */
1473         if (!isatty(fileno(stdin)))
1474                 unset_nonblock(fileno(stdin));
1475         if (!isatty(fileno(stdout)))
1476                 unset_nonblock(fileno(stdout));
1477         if (!isatty(fileno(stderr)))
1478                 unset_nonblock(fileno(stderr));
1479
1480         /*
1481          * If there was no shell or command requested, there will be no remote
1482          * exit status to be returned.  In that case, clear error code if the
1483          * connection was deliberately terminated at this end.
1484          */
1485         if (no_shell_flag && received_signal == SIGTERM) {
1486                 received_signal = 0;
1487                 exit_status = 0;
1488         }
1489
1490         if (received_signal)
1491                 fatal("Killed by signal %d.", (int) received_signal);
1492
1493         /*
1494          * In interactive mode (with pseudo tty) display a message indicating
1495          * that the connection has been closed.
1496          */
1497         if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1498                 snprintf(buf, sizeof buf,
1499                     "Connection to %.64s closed.\r\n", host);
1500                 buffer_append(&stderr_buffer, buf, strlen(buf));
1501         }
1502
1503         /* Output any buffered data for stdout. */
1504         while (buffer_len(&stdout_buffer) > 0) {
1505                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1506                     buffer_len(&stdout_buffer));
1507                 if (len <= 0) {
1508                         error("Write failed flushing stdout buffer.");
1509                         break;
1510                 }
1511                 buffer_consume(&stdout_buffer, len);
1512                 stdout_bytes += len;
1513         }
1514
1515         /* Output any buffered data for stderr. */
1516         while (buffer_len(&stderr_buffer) > 0) {
1517                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1518                     buffer_len(&stderr_buffer));
1519                 if (len <= 0) {
1520                         error("Write failed flushing stderr buffer.");
1521                         break;
1522                 }
1523                 buffer_consume(&stderr_buffer, len);
1524                 stderr_bytes += len;
1525         }
1526
1527         /* Clear and free any buffers. */
1528         memset(buf, 0, sizeof(buf));
1529         buffer_free(&stdin_buffer);
1530         buffer_free(&stdout_buffer);
1531         buffer_free(&stderr_buffer);
1532
1533         /* Report bytes transferred, and transfer rates. */
1534         total_time = get_current_time() - start_time;
1535         debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f "
1536             "seconds", stdin_bytes, stdout_bytes, stderr_bytes, total_time);
1537         if (total_time > 0)
1538                 debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
1539                     stdin_bytes / total_time, stdout_bytes / total_time,
1540                     stderr_bytes / total_time);
1541
1542         /* Return the exit status of the program. */
1543         debug("Exit status %d", exit_status);
1544         return exit_status;
1545 }
1546
1547 /*********/
1548
1549 static void
1550 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1551 {
1552         u_int data_len;
1553         char *data = packet_get_string(&data_len);
1554         packet_check_eom();
1555         buffer_append(&stdout_buffer, data, data_len);
1556         memset(data, 0, data_len);
1557         xfree(data);
1558 }
1559 static void
1560 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1561 {
1562         u_int data_len;
1563         char *data = packet_get_string(&data_len);
1564         packet_check_eom();
1565         buffer_append(&stderr_buffer, data, data_len);
1566         memset(data, 0, data_len);
1567         xfree(data);
1568 }
1569 static void
1570 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1571 {
1572         exit_status = packet_get_int();
1573         packet_check_eom();
1574         /* Acknowledge the exit. */
1575         packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1576         packet_send();
1577         /*
1578          * Must wait for packet to be sent since we are
1579          * exiting the loop.
1580          */
1581         packet_write_wait();
1582         /* Flag that we want to exit. */
1583         quit_pending = 1;
1584 }
1585 static void
1586 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1587 {
1588         Channel *c = NULL;
1589         int remote_id, sock;
1590
1591         /* Read the remote channel number from the message. */
1592         remote_id = packet_get_int();
1593         packet_check_eom();
1594
1595         /*
1596          * Get a connection to the local authentication agent (this may again
1597          * get forwarded).
1598          */
1599         sock = ssh_get_authentication_socket();
1600
1601         /*
1602          * If we could not connect the agent, send an error message back to
1603          * the server. This should never happen unless the agent dies,
1604          * because authentication forwarding is only enabled if we have an
1605          * agent.
1606          */
1607         if (sock >= 0) {
1608                 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1609                     -1, 0, 0, 0, "authentication agent connection", 1);
1610                 c->remote_id = remote_id;
1611                 c->force_drain = 1;
1612         }
1613         if (c == NULL) {
1614                 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1615                 packet_put_int(remote_id);
1616         } else {
1617                 /* Send a confirmation to the remote host. */
1618                 debug("Forwarding authentication connection.");
1619                 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1620                 packet_put_int(remote_id);
1621                 packet_put_int(c->self);
1622         }
1623         packet_send();
1624 }
1625
1626 static Channel *
1627 client_request_forwarded_tcpip(const char *request_type, int rchan)
1628 {
1629         Channel *c = NULL;
1630         char *listen_address, *originator_address;
1631         int listen_port, originator_port;
1632
1633         /* Get rest of the packet */
1634         listen_address = packet_get_string(NULL);
1635         listen_port = packet_get_int();
1636         originator_address = packet_get_string(NULL);
1637         originator_port = packet_get_int();
1638         packet_check_eom();
1639
1640         debug("client_request_forwarded_tcpip: listen %s port %d, "
1641             "originator %s port %d", listen_address, listen_port,
1642             originator_address, originator_port);
1643
1644         c = channel_connect_by_listen_address(listen_port,
1645             "forwarded-tcpip", originator_address);
1646
1647         xfree(originator_address);
1648         xfree(listen_address);
1649         return c;
1650 }
1651
1652 static Channel *
1653 client_request_x11(const char *request_type, int rchan)
1654 {
1655         Channel *c = NULL;
1656         char *originator;
1657         int originator_port;
1658         int sock;
1659
1660         if (!options.forward_x11) {
1661                 error("Warning: ssh server tried X11 forwarding.");
1662                 error("Warning: this is probably a break-in attempt by a "
1663                     "malicious server.");
1664                 return NULL;
1665         }
1666         originator = packet_get_string(NULL);
1667         if (datafellows & SSH_BUG_X11FWD) {
1668                 debug2("buggy server: x11 request w/o originator_port");
1669                 originator_port = 0;
1670         } else {
1671                 originator_port = packet_get_int();
1672         }
1673         packet_check_eom();
1674         /* XXX check permission */
1675         debug("client_request_x11: request from %s %d", originator,
1676             originator_port);
1677         xfree(originator);
1678         sock = x11_connect_display();
1679         if (sock < 0)
1680                 return NULL;
1681         c = channel_new("x11",
1682             SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1683             CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1684         c->force_drain = 1;
1685         return c;
1686 }
1687
1688 static Channel *
1689 client_request_agent(const char *request_type, int rchan)
1690 {
1691         Channel *c = NULL;
1692         int sock;
1693
1694         if (!options.forward_agent) {
1695                 error("Warning: ssh server tried agent forwarding.");
1696                 error("Warning: this is probably a break-in attempt by a "
1697                     "malicious server.");
1698                 return NULL;
1699         }
1700         sock = ssh_get_authentication_socket();
1701         if (sock < 0)
1702                 return NULL;
1703         c = channel_new("authentication agent connection",
1704             SSH_CHANNEL_OPEN, sock, sock, -1,
1705             CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0,
1706             "authentication agent connection", 1);
1707         c->force_drain = 1;
1708         return c;
1709 }
1710
1711 int
1712 client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
1713 {
1714         Channel *c;
1715         int fd;
1716
1717         if (tun_mode == SSH_TUNMODE_NO)
1718                 return 0;
1719
1720         if (!compat20) {
1721                 error("Tunnel forwarding is not support for protocol 1");
1722                 return -1;
1723         }
1724
1725         debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
1726
1727         /* Open local tunnel device */
1728         if ((fd = tun_open(local_tun, tun_mode)) == -1) {
1729                 error("Tunnel device open failed.");
1730                 return -1;
1731         }
1732
1733         c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1734             CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1);
1735         c->datagram = 1;
1736
1737 #if defined(SSH_TUN_FILTER)
1738         if (options.tun_open == SSH_TUNMODE_POINTOPOINT)
1739                 channel_register_filter(c->self, sys_tun_infilter,
1740                     sys_tun_outfilter);
1741 #endif
1742
1743         packet_start(SSH2_MSG_CHANNEL_OPEN);
1744         packet_put_cstring("tun@openssh.com");
1745         packet_put_int(c->self);
1746         packet_put_int(c->local_window_max);
1747         packet_put_int(c->local_maxpacket);
1748         packet_put_int(tun_mode);
1749         packet_put_int(remote_tun);
1750         packet_send();
1751
1752         return 0;
1753 }
1754
1755 /* XXXX move to generic input handler */
1756 static void
1757 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1758 {
1759         Channel *c = NULL;
1760         char *ctype;
1761         int rchan;
1762         u_int rmaxpack, rwindow, len;
1763
1764         ctype = packet_get_string(&len);
1765         rchan = packet_get_int();
1766         rwindow = packet_get_int();
1767         rmaxpack = packet_get_int();
1768
1769         debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1770             ctype, rchan, rwindow, rmaxpack);
1771
1772         if (strcmp(ctype, "forwarded-tcpip") == 0) {
1773                 c = client_request_forwarded_tcpip(ctype, rchan);
1774         } else if (strcmp(ctype, "x11") == 0) {
1775                 c = client_request_x11(ctype, rchan);
1776         } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1777                 c = client_request_agent(ctype, rchan);
1778         }
1779 /* XXX duplicate : */
1780         if (c != NULL) {
1781                 debug("confirm %s", ctype);
1782                 c->remote_id = rchan;
1783                 c->remote_window = rwindow;
1784                 c->remote_maxpacket = rmaxpack;
1785                 if (c->type != SSH_CHANNEL_CONNECTING) {
1786                         packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1787                         packet_put_int(c->remote_id);
1788                         packet_put_int(c->self);
1789                         packet_put_int(c->local_window);
1790                         packet_put_int(c->local_maxpacket);
1791                         packet_send();
1792                 }
1793         } else {
1794                 debug("failure %s", ctype);
1795                 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1796                 packet_put_int(rchan);
1797                 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1798                 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1799                         packet_put_cstring("open failed");
1800                         packet_put_cstring("");
1801                 }
1802                 packet_send();
1803         }
1804         xfree(ctype);
1805 }
1806 static void
1807 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1808 {
1809         Channel *c = NULL;
1810         int exitval, id, reply, success = 0;
1811         char *rtype;
1812
1813         id = packet_get_int();
1814         rtype = packet_get_string(NULL);
1815         reply = packet_get_char();
1816
1817         debug("client_input_channel_req: channel %d rtype %s reply %d",
1818             id, rtype, reply);
1819
1820         if (id == -1) {
1821                 error("client_input_channel_req: request for channel -1");
1822         } else if ((c = channel_lookup(id)) == NULL) {
1823                 error("client_input_channel_req: channel %d: "
1824                     "unknown channel", id);
1825         } else if (strcmp(rtype, "eow@openssh.com") == 0) {
1826                 packet_check_eom();
1827                 chan_rcvd_eow(c);
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 {
1874         int len;
1875         Channel *c = NULL;
1876
1877         debug2("%s: id %d", __func__, id);
1878
1879         if ((c = channel_lookup(id)) == NULL)
1880                 fatal("client_session2_setup: channel %d: unknown channel", id);
1881
1882         if (want_tty) {
1883                 struct winsize ws;
1884
1885                 /* Store window size in the packet. */
1886                 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
1887                         memset(&ws, 0, sizeof(ws));
1888
1889                 channel_request_start(id, "pty-req", 1);
1890                 client_expect_confirm(id, "PTY allocation", 0);
1891                 packet_put_cstring(term != NULL ? term : "");
1892                 packet_put_int((u_int)ws.ws_col);
1893                 packet_put_int((u_int)ws.ws_row);
1894                 packet_put_int((u_int)ws.ws_xpixel);
1895                 packet_put_int((u_int)ws.ws_ypixel);
1896                 if (tiop == NULL)
1897                         tiop = get_saved_tio();
1898                 tty_make_modes(-1, tiop);
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",
1947                             len, (u_char*)buffer_ptr(cmd));
1948                         channel_request_start(id, "subsystem", 1);
1949                         client_expect_confirm(id, "subsystem", 1);
1950                 } else {
1951                         debug("Sending command: %.*s",
1952                             len, (u_char*)buffer_ptr(cmd));
1953                         channel_request_start(id, "exec", 1);
1954                         client_expect_confirm(id, "exec", 1);
1955                 }
1956                 packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
1957                 packet_send();
1958         } else {
1959                 channel_request_start(id, "shell", 1);
1960                 client_expect_confirm(id, "shell", 1);
1961                 packet_send();
1962         }
1963 }
1964
1965 static void
1966 client_init_dispatch_20(void)
1967 {
1968         dispatch_init(&dispatch_protocol_error);
1969
1970         dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1971         dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1972         dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1973         dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1974         dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1975         dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1976         dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1977         dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1978         dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1979         dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
1980         dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
1981         dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1982
1983         /* rekeying */
1984         dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1985
1986         /* global request reply messages */
1987         dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
1988         dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1989 }
1990
1991 static void
1992 client_init_dispatch_13(void)
1993 {
1994         dispatch_init(NULL);
1995         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1996         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1997         dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1998         dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1999         dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2000         dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2001         dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2002         dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2003         dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
2004
2005         dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
2006             &client_input_agent_open : &deny_input_open);
2007         dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2008             &x11_input_open : &deny_input_open);
2009 }
2010
2011 static void
2012 client_init_dispatch_15(void)
2013 {
2014         client_init_dispatch_13();
2015         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2016         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2017 }
2018
2019 static void
2020 client_init_dispatch(void)
2021 {
2022         if (compat20)
2023                 client_init_dispatch_20();
2024         else if (compat13)
2025                 client_init_dispatch_13();
2026         else
2027                 client_init_dispatch_15();
2028 }
2029
2030 /* client specific fatal cleanup */
2031 void
2032 cleanup_exit(int i)
2033 {
2034         leave_raw_mode();
2035         leave_non_blocking();
2036         if (options.control_path != NULL && muxserver_sock != -1)
2037                 unlink(options.control_path);
2038         _exit(i);
2039 }