clientloop.c

   1 /* $OpenBSD: clientloop.c,v 1.170 2006/07/22 20:48:22 stevesk 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 #include <errno.h>
  73 #ifdef HAVE_PATHS_H
  74 #include <paths.h>
  75 #endif
  76 #include <signal.h>
  77 #include <string.h>
  78 #include <termios.h>
  79 #include <unistd.h>
  80
  81 #include "ssh.h"
  82 #include "ssh1.h"
  83 #include "ssh2.h"
  84 #include "xmalloc.h"
  85 #include "packet.h"
  86 #include "buffer.h"
  87 #include "compat.h"
  88 #include "channels.h"
  89 #include "dispatch.h"
  90 #include "buffer.h"
  91 #include "bufaux.h"
  92 #include "key.h"
  93 #include "kex.h"
  94 #include "log.h"
  95 #include "readconf.h"
  96 #include "clientloop.h"
  97 #include "sshconnect.h"
  98 #include "authfd.h"
  99 #include "atomicio.h"
 100 #include "sshpty.h"
 101 #include "misc.h"
 102 #include "monitor_fdpass.h"
 103 #include "match.h"
 104 #include "msg.h"
 105
 106 /* import options */
 107 extern Options options;
 108
 109 /* Flag indicating that stdin should be redirected from /dev/null. */
 110 extern int stdin_null_flag;
 111
 112 /* Flag indicating that no shell has been requested */
 113 extern int no_shell_flag;
 114
 115 /* Control socket */
 116 extern int control_fd;
 117
 118 /*
 119  * Name of the host we are connecting to.  This is the name given on the
 120  * command line, or the HostName specified for the user-supplied name in a
 121  * configuration file.
 122  */
 123 extern char *host;
 124
 125 /*
 126  * Flag to indicate that we have received a window change signal which has
 127  * not yet been processed.  This will cause a message indicating the new
 128  * window size to be sent to the server a little later.  This is volatile
 129  * because this is updated in a signal handler.
 130  */
 131 static volatile sig_atomic_t received_window_change_signal = 0;
 132 static volatile sig_atomic_t received_signal = 0;
 133
 134 /* Flag indicating whether the user's terminal is in non-blocking mode. */
 135 static int in_non_blocking_mode = 0;
 136
 137 /* Common data for the client loop code. */
 138 static volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
 139 static int escape_char;         /* Escape character. */
 140 static int escape_pending;      /* Last character was the escape character */
 141 static int last_was_cr;         /* Last character was a newline. */
 142 static int exit_status;         /* Used to store the exit status of the command. */
 143 static int stdin_eof;           /* EOF has been encountered on standard error. */
 144 static Buffer stdin_buffer;     /* Buffer for stdin data. */
 145 static Buffer stdout_buffer;    /* Buffer for stdout data. */
 146 static Buffer stderr_buffer;    /* Buffer for stderr data. */
 147 static u_long stdin_bytes, stdout_bytes, stderr_bytes;
 148 static u_int buffer_high;/* Soft max buffer size. */
 149 static int connection_in;       /* Connection to server (input). */
 150 static int connection_out;      /* Connection to server (output). */
 151 static int need_rekeying;       /* Set to non-zero if rekeying is requested. */
 152 static int session_closed = 0;  /* In SSH2: login session closed. */
 153 static int server_alive_timeouts = 0;
 154
 155 static void client_init_dispatch(void);
 156 int     session_ident = -1;
 157
 158 struct confirm_ctx {
 159         int want_tty;
 160         int want_subsys;
 161         int want_x_fwd;
 162         int want_agent_fwd;
 163         Buffer cmd;
 164         char *term;
 165         struct termios tio;
 166         char **env;
 167 };
 168
 169 /*XXX*/
 170 extern Kex *xxx_kex;
 171
 172 void ssh_process_session2_setup(int, int, int, Buffer *);
 173
 174 /* Restores stdin to blocking mode. */
 175
 176 static void
 177 leave_non_blocking(void)
 178 {
 179         if (in_non_blocking_mode) {
 180                 unset_nonblock(fileno(stdin));
 181                 in_non_blocking_mode = 0;
 182         }
 183 }
 184
 185 /* Puts stdin terminal in non-blocking mode. */
 186
 187 static void
 188 enter_non_blocking(void)
 189 {
 190         in_non_blocking_mode = 1;
 191         set_nonblock(fileno(stdin));
 192 }
 193
 194 /*
 195  * Signal handler for the window change signal (SIGWINCH).  This just sets a
 196  * flag indicating that the window has changed.
 197  */
 198 /*ARGSUSED */
 199 static void
 200 window_change_handler(int sig)
 201 {
 202         received_window_change_signal = 1;
 203         signal(SIGWINCH, window_change_handler);
 204 }
 205
 206 /*
 207  * Signal handler for signals that cause the program to terminate.  These
 208  * signals must be trapped to restore terminal modes.
 209  */
 210 /*ARGSUSED */
 211 static void
 212 signal_handler(int sig)
 213 {
 214         received_signal = sig;
 215         quit_pending = 1;
 216 }
 217
 218 /*
 219  * Returns current time in seconds from Jan 1, 1970 with the maximum
 220  * available resolution.
 221  */
 222
 223 static double
 224 get_current_time(void)
 225 {
 226         struct timeval tv;
 227         gettimeofday(&tv, NULL);
 228         return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
 229 }
 230
 231 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
 232 void
 233 client_x11_get_proto(const char *display, const char *xauth_path,
 234     u_int trusted, char **_proto, char **_data)
 235 {
 236         char cmd[1024];
 237         char line[512];
 238         char xdisplay[512];
 239         static char proto[512], data[512];
 240         FILE *f;
 241         int got_data = 0, generated = 0, do_unlink = 0, i;
 242         char *xauthdir, *xauthfile;
 243         struct stat st;
 244
 245         xauthdir = xauthfile = NULL;
 246         *_proto = proto;
 247         *_data = data;
 248         proto[0] = data[0] = '\0';
 249
 250         if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
 251                 debug("No xauth program.");
 252         } else {
 253                 if (display == NULL) {
 254                         debug("x11_get_proto: DISPLAY not set");
 255                         return;
 256                 }
 257                 /*
 258                  * Handle FamilyLocal case where $DISPLAY does
 259                  * not match an authorization entry.  For this we
 260                  * just try "xauth list unix:displaynum.screennum".
 261                  * XXX: "localhost" match to determine FamilyLocal
 262                  *      is not perfect.
 263                  */
 264                 if (strncmp(display, "localhost:", 10) == 0) {
 265                         snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
 266                             display + 10);
 267                         display = xdisplay;
 268                 }
 269                 if (trusted == 0) {
 270                         xauthdir = xmalloc(MAXPATHLEN);
 271                         xauthfile = xmalloc(MAXPATHLEN);
 272                         strlcpy(xauthdir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
 273                         if (mkdtemp(xauthdir) != NULL) {
 274                                 do_unlink = 1;
 275                                 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
 276                                     xauthdir);
 277                                 snprintf(cmd, sizeof(cmd),
 278                                     "%s -f %s generate %s " SSH_X11_PROTO
 279                                     " untrusted timeout 1200 2>" _PATH_DEVNULL,
 280                                     xauth_path, xauthfile, display);
 281                                 debug2("x11_get_proto: %s", cmd);
 282                                 if (system(cmd) == 0)
 283                                         generated = 1;
 284                         }
 285                 }
 286                 snprintf(cmd, sizeof(cmd),
 287                     "%s %s%s list %s 2>" _PATH_DEVNULL,
 288                     xauth_path,
 289                     generated ? "-f " : "" ,
 290                     generated ? xauthfile : "",
 291                     display);
 292                 debug2("x11_get_proto: %s", cmd);
 293                 f = popen(cmd, "r");
 294                 if (f && fgets(line, sizeof(line), f) &&
 295                     sscanf(line, "%*s %511s %511s", proto, data) == 2)
 296                         got_data = 1;
 297                 if (f)
 298                         pclose(f);
 299         }
 300
 301         if (do_unlink) {
 302                 unlink(xauthfile);
 303                 rmdir(xauthdir);
 304         }
 305         if (xauthdir)
 306                 xfree(xauthdir);
 307         if (xauthfile)
 308                 xfree(xauthfile);
 309
 310         /*
 311          * If we didn't get authentication data, just make up some
 312          * data.  The forwarding code will check the validity of the
 313          * response anyway, and substitute this data.  The X11
 314          * server, however, will ignore this fake data and use
 315          * whatever authentication mechanisms it was using otherwise
 316          * for the local connection.
 317          */
 318         if (!got_data) {
 319                 u_int32_t rnd = 0;
 320
 321                 logit("Warning: No xauth data; "
 322                     "using fake authentication data for X11 forwarding.");
 323                 strlcpy(proto, SSH_X11_PROTO, sizeof proto);
 324                 for (i = 0; i < 16; i++) {
 325                         if (i % 4 == 0)
 326                                 rnd = arc4random();
 327                         snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
 328                             rnd & 0xff);
 329                         rnd >>= 8;
 330                 }
 331         }
 332 }
 333
 334 /*
 335  * This is called when the interactive is entered.  This checks if there is
 336  * an EOF coming on stdin.  We must check this explicitly, as select() does
 337  * not appear to wake up when redirecting from /dev/null.
 338  */
 339
 340 static void
 341 client_check_initial_eof_on_stdin(void)
 342 {
 343         int len;
 344         char buf[1];
 345
 346         /*
 347          * If standard input is to be "redirected from /dev/null", we simply
 348          * mark that we have seen an EOF and send an EOF message to the
 349          * server. Otherwise, we try to read a single character; it appears
 350          * that for some files, such /dev/null, select() never wakes up for
 351          * read for this descriptor, which means that we never get EOF.  This
 352          * way we will get the EOF if stdin comes from /dev/null or similar.
 353          */
 354         if (stdin_null_flag) {
 355                 /* Fake EOF on stdin. */
 356                 debug("Sending eof.");
 357                 stdin_eof = 1;
 358                 packet_start(SSH_CMSG_EOF);
 359                 packet_send();
 360         } else {
 361                 enter_non_blocking();
 362
 363                 /* Check for immediate EOF on stdin. */
 364                 len = read(fileno(stdin), buf, 1);
 365                 if (len == 0) {
 366                         /* EOF.  Record that we have seen it and send EOF to server. */
 367                         debug("Sending eof.");
 368                         stdin_eof = 1;
 369                         packet_start(SSH_CMSG_EOF);
 370                         packet_send();
 371                 } else if (len > 0) {
 372                         /*
 373                          * Got data.  We must store the data in the buffer,
 374                          * and also process it as an escape character if
 375                          * appropriate.
 376                          */
 377                         if ((u_char) buf[0] == escape_char)
 378                                 escape_pending = 1;
 379                         else
 380                                 buffer_append(&stdin_buffer, buf, 1);
 381                 }
 382                 leave_non_blocking();
 383         }
 384 }
 385
 386
 387 /*
 388  * Make packets from buffered stdin data, and buffer them for sending to the
 389  * connection.
 390  */
 391
 392 static void
 393 client_make_packets_from_stdin_data(void)
 394 {
 395         u_int len;
 396
 397         /* Send buffered stdin data to the server. */
 398         while (buffer_len(&stdin_buffer) > 0 &&
 399             packet_not_very_much_data_to_write()) {
 400                 len = buffer_len(&stdin_buffer);
 401                 /* Keep the packets at reasonable size. */
 402                 if (len > packet_get_maxsize())
 403                         len = packet_get_maxsize();
 404                 packet_start(SSH_CMSG_STDIN_DATA);
 405                 packet_put_string(buffer_ptr(&stdin_buffer), len);
 406                 packet_send();
 407                 buffer_consume(&stdin_buffer, len);
 408                 stdin_bytes += len;
 409                 /* If we have a pending EOF, send it now. */
 410                 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
 411                         packet_start(SSH_CMSG_EOF);
 412                         packet_send();
 413                 }
 414         }
 415 }
 416
 417 /*
 418  * Checks if the client window has changed, and sends a packet about it to
 419  * the server if so.  The actual change is detected elsewhere (by a software
 420  * interrupt on Unix); this just checks the flag and sends a message if
 421  * appropriate.
 422  */
 423
 424 static void
 425 client_check_window_change(void)
 426 {
 427         struct winsize ws;
 428
 429         if (! received_window_change_signal)
 430                 return;
 431         /** XXX race */
 432         received_window_change_signal = 0;
 433
 434         debug2("client_check_window_change: changed");
 435
 436         if (compat20) {
 437                 channel_send_window_changes();
 438         } else {
 439                 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
 440                         return;
 441                 packet_start(SSH_CMSG_WINDOW_SIZE);
 442                 packet_put_int((u_int)ws.ws_row);
 443                 packet_put_int((u_int)ws.ws_col);
 444                 packet_put_int((u_int)ws.ws_xpixel);
 445                 packet_put_int((u_int)ws.ws_ypixel);
 446                 packet_send();
 447         }
 448 }
 449
 450 static void
 451 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
 452 {
 453         server_alive_timeouts = 0;
 454         client_global_request_reply_fwd(type, seq, ctxt);
 455 }
 456
 457 static void
 458 server_alive_check(void)
 459 {
 460         if (++server_alive_timeouts > options.server_alive_count_max)
 461                 packet_disconnect("Timeout, server not responding.");
 462         packet_start(SSH2_MSG_GLOBAL_REQUEST);
 463         packet_put_cstring("keepalive@openssh.com");
 464         packet_put_char(1);     /* boolean: want reply */
 465         packet_send();
 466 }
 467
 468 /*
 469  * Waits until the client can do something (some data becomes available on
 470  * one of the file descriptors).
 471  */
 472 static void
 473 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
 474     int *maxfdp, u_int *nallocp, int rekeying)
 475 {
 476         struct timeval tv, *tvp;
 477         int ret;
 478
 479         /* Add any selections by the channel mechanism. */
 480         channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
 481
 482         if (!compat20) {
 483                 /* Read from the connection, unless our buffers are full. */
 484                 if (buffer_len(&stdout_buffer) < buffer_high &&
 485                     buffer_len(&stderr_buffer) < buffer_high &&
 486                     channel_not_very_much_buffered_data())
 487                         FD_SET(connection_in, *readsetp);
 488                 /*
 489                  * Read from stdin, unless we have seen EOF or have very much
 490                  * buffered data to send to the server.
 491                  */
 492                 if (!stdin_eof && packet_not_very_much_data_to_write())
 493                         FD_SET(fileno(stdin), *readsetp);
 494
 495                 /* Select stdout/stderr if have data in buffer. */
 496                 if (buffer_len(&stdout_buffer) > 0)
 497                         FD_SET(fileno(stdout), *writesetp);
 498                 if (buffer_len(&stderr_buffer) > 0)
 499                         FD_SET(fileno(stderr), *writesetp);
 500         } else {
 501                 /* channel_prepare_select could have closed the last channel */
 502                 if (session_closed && !channel_still_open() &&
 503                     !packet_have_data_to_write()) {
 504                         /* clear mask since we did not call select() */
 505                         memset(*readsetp, 0, *nallocp);
 506                         memset(*writesetp, 0, *nallocp);
 507                         return;
 508                 } else {
 509                         FD_SET(connection_in, *readsetp);
 510                 }
 511         }
 512
 513         /* Select server connection if have data to write to the server. */
 514         if (packet_have_data_to_write())
 515                 FD_SET(connection_out, *writesetp);
 516
 517         if (control_fd != -1)
 518                 FD_SET(control_fd, *readsetp);
 519
 520         /*
 521          * Wait for something to happen.  This will suspend the process until
 522          * some selected descriptor can be read, written, or has some other
 523          * event pending.
 524          */
 525
 526         if (options.server_alive_interval == 0 || !compat20)
 527                 tvp = NULL;
 528         else {
 529                 tv.tv_sec = options.server_alive_interval;
 530                 tv.tv_usec = 0;
 531                 tvp = &tv;
 532         }
 533         ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
 534         if (ret < 0) {
 535                 char buf[100];
 536
 537                 /*
 538                  * We have to clear the select masks, because we return.
 539                  * We have to return, because the mainloop checks for the flags
 540                  * set by the signal handlers.
 541                  */
 542                 memset(*readsetp, 0, *nallocp);
 543                 memset(*writesetp, 0, *nallocp);
 544
 545                 if (errno == EINTR)
 546                         return;
 547                 /* Note: we might still have data in the buffers. */
 548                 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
 549                 buffer_append(&stderr_buffer, buf, strlen(buf));
 550                 quit_pending = 1;
 551         } else if (ret == 0)
 552                 server_alive_check();
 553 }
 554
 555 static void
 556 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
 557 {
 558         /* Flush stdout and stderr buffers. */
 559         if (buffer_len(bout) > 0)
 560                 atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
 561         if (buffer_len(berr) > 0)
 562                 atomicio(vwrite, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
 563
 564         leave_raw_mode();
 565
 566         /*
 567          * Free (and clear) the buffer to reduce the amount of data that gets
 568          * written to swap.
 569          */
 570         buffer_free(bin);
 571         buffer_free(bout);
 572         buffer_free(berr);
 573
 574         /* Send the suspend signal to the program itself. */
 575         kill(getpid(), SIGTSTP);
 576
 577         /* Reset window sizes in case they have changed */
 578         received_window_change_signal = 1;
 579
 580         /* OK, we have been continued by the user. Reinitialize buffers. */
 581         buffer_init(bin);
 582         buffer_init(bout);
 583         buffer_init(berr);
 584
 585         enter_raw_mode();
 586 }
 587
 588 static void
 589 client_process_net_input(fd_set *readset)
 590 {
 591         int len;
 592         char buf[8192];
 593
 594         /*
 595          * Read input from the server, and add any such data to the buffer of
 596          * the packet subsystem.
 597          */
 598         if (FD_ISSET(connection_in, readset)) {
 599                 /* Read as much as possible. */
 600                 len = read(connection_in, buf, sizeof(buf));
 601                 if (len == 0) {
 602                         /* Received EOF.  The remote host has closed the connection. */
 603                         snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
 604                                  host);
 605                         buffer_append(&stderr_buffer, buf, strlen(buf));
 606                         quit_pending = 1;
 607                         return;
 608                 }
 609                 /*
 610                  * There is a kernel bug on Solaris that causes select to
 611                  * sometimes wake up even though there is no data available.
 612                  */
 613                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
 614                         len = 0;
 615
 616                 if (len < 0) {
 617                         /* An error has encountered.  Perhaps there is a network problem. */
 618                         snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
 619                                  host, strerror(errno));
 620                         buffer_append(&stderr_buffer, buf, strlen(buf));
 621                         quit_pending = 1;
 622                         return;
 623                 }
 624                 packet_process_incoming(buf, len);
 625         }
 626 }
 627
 628 static void
 629 client_subsystem_reply(int type, u_int32_t seq, void *ctxt)
 630 {
 631         int id;
 632         Channel *c;
 633
 634         id = packet_get_int();
 635         packet_check_eom();
 636
 637         if ((c = channel_lookup(id)) == NULL) {
 638                 error("%s: no channel for id %d", __func__, id);
 639                 return;
 640         }
 641
 642         if (type == SSH2_MSG_CHANNEL_SUCCESS)
 643                 debug2("Request suceeded on channel %d", id);
 644         else if (type == SSH2_MSG_CHANNEL_FAILURE) {
 645                 error("Request failed on channel %d", id);
 646                 channel_free(c);
 647         }
 648 }
 649
 650 static void
 651 client_extra_session2_setup(int id, void *arg)
 652 {
 653         struct confirm_ctx *cctx = arg;
 654         const char *display;
 655         Channel *c;
 656         int i;
 657
 658         if (cctx == NULL)
 659                 fatal("%s: cctx == NULL", __func__);
 660         if ((c = channel_lookup(id)) == NULL)
 661                 fatal("%s: no channel for id %d", __func__, id);
 662
 663         display = getenv("DISPLAY");
 664         if (cctx->want_x_fwd && options.forward_x11 && display != NULL) {
 665                 char *proto, *data;
 666                 /* Get reasonable local authentication information. */
 667                 client_x11_get_proto(display, options.xauth_location,
 668                     options.forward_x11_trusted, &proto, &data);
 669                 /* Request forwarding with authentication spoofing. */
 670                 debug("Requesting X11 forwarding with authentication spoofing.");
 671                 x11_request_forwarding_with_spoofing(id, display, proto, data);
 672                 /* XXX wait for reply */
 673         }
 674
 675         if (cctx->want_agent_fwd && options.forward_agent) {
 676                 debug("Requesting authentication agent forwarding.");
 677                 channel_request_start(id, "auth-agent-req@openssh.com", 0);
 678                 packet_send();
 679         }
 680
 681         client_session2_setup(id, cctx->want_tty, cctx->want_subsys,
 682             cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env,
 683             client_subsystem_reply);
 684
 685         c->confirm_ctx = NULL;
 686         buffer_free(&cctx->cmd);
 687         xfree(cctx->term);
 688         if (cctx->env != NULL) {
 689                 for (i = 0; cctx->env[i] != NULL; i++)
 690                         xfree(cctx->env[i]);
 691                 xfree(cctx->env);
 692         }
 693         xfree(cctx);
 694 }
 695
 696 static void
 697 client_process_control(fd_set *readset)
 698 {
 699         Buffer m;
 700         Channel *c;
 701         int client_fd, new_fd[3], ver, allowed;
 702         socklen_t addrlen;
 703         struct sockaddr_storage addr;
 704         struct confirm_ctx *cctx;
 705         char *cmd;
 706         u_int i, len, env_len, command, flags;
 707         uid_t euid;
 708         gid_t egid;
 709
 710         /*
 711          * Accept connection on control socket
 712          */
 713         if (control_fd == -1 || !FD_ISSET(control_fd, readset))
 714                 return;
 715
 716         memset(&addr, 0, sizeof(addr));
 717         addrlen = sizeof(addr);
 718         if ((client_fd = accept(control_fd,
 719             (struct sockaddr*)&addr, &addrlen)) == -1) {
 720                 error("%s accept: %s", __func__, strerror(errno));
 721                 return;
 722         }
 723
 724         if (getpeereid(client_fd, &euid, &egid) < 0) {
 725                 error("%s getpeereid failed: %s", __func__, strerror(errno));
 726                 close(client_fd);
 727                 return;
 728         }
 729         if ((euid != 0) && (getuid() != euid)) {
 730                 error("control mode uid mismatch: peer euid %u != uid %u",
 731                     (u_int) euid, (u_int) getuid());
 732                 close(client_fd);
 733                 return;
 734         }
 735
 736         unset_nonblock(client_fd);
 737
 738         /* Read command */
 739         buffer_init(&m);
 740         if (ssh_msg_recv(client_fd, &m) == -1) {
 741                 error("%s: client msg_recv failed", __func__);
 742                 close(client_fd);
 743                 buffer_free(&m);
 744                 return;
 745         }
 746         if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
 747                 error("%s: wrong client version %d", __func__, ver);
 748                 buffer_free(&m);
 749                 close(client_fd);
 750                 return;
 751         }
 752
 753         allowed = 1;
 754         command = buffer_get_int(&m);
 755         flags = buffer_get_int(&m);
 756
 757         buffer_clear(&m);
 758
 759         switch (command) {
 760         case SSHMUX_COMMAND_OPEN:
 761                 if (options.control_master == SSHCTL_MASTER_ASK ||
 762                     options.control_master == SSHCTL_MASTER_AUTO_ASK)
 763                         allowed = ask_permission("Allow shared connection "
 764                             "to %s? ", host);
 765                 /* continue below */
 766                 break;
 767         case SSHMUX_COMMAND_TERMINATE:
 768                 if (options.control_master == SSHCTL_MASTER_ASK ||
 769                     options.control_master == SSHCTL_MASTER_AUTO_ASK)
 770                         allowed = ask_permission("Terminate shared connection "
 771                             "to %s? ", host);
 772                 if (allowed)
 773                         quit_pending = 1;
 774                 /* FALLTHROUGH */
 775         case SSHMUX_COMMAND_ALIVE_CHECK:
 776                 /* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */
 777                 buffer_clear(&m);
 778                 buffer_put_int(&m, allowed);
 779                 buffer_put_int(&m, getpid());
 780                 if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 781                         error("%s: client msg_send failed", __func__);
 782                         close(client_fd);
 783                         buffer_free(&m);
 784                         return;
 785                 }
 786                 buffer_free(&m);
 787                 close(client_fd);
 788                 return;
 789         default:
 790                 error("Unsupported command %d", command);
 791                 buffer_free(&m);
 792                 close(client_fd);
 793                 return;
 794         }
 795
 796         /* Reply for SSHMUX_COMMAND_OPEN */
 797         buffer_clear(&m);
 798         buffer_put_int(&m, allowed);
 799         buffer_put_int(&m, getpid());
 800         if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 801                 error("%s: client msg_send failed", __func__);
 802                 close(client_fd);
 803                 buffer_free(&m);
 804                 return;
 805         }
 806
 807         if (!allowed) {
 808                 error("Refused control connection");
 809                 close(client_fd);
 810                 buffer_free(&m);
 811                 return;
 812         }
 813
 814         buffer_clear(&m);
 815         if (ssh_msg_recv(client_fd, &m) == -1) {
 816                 error("%s: client msg_recv failed", __func__);
 817                 close(client_fd);
 818                 buffer_free(&m);
 819                 return;
 820         }
 821         if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
 822                 error("%s: wrong client version %d", __func__, ver);
 823                 buffer_free(&m);
 824                 close(client_fd);
 825                 return;
 826         }
 827
 828         cctx = xcalloc(1, sizeof(*cctx));
 829         cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0;
 830         cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0;
 831         cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0;
 832         cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0;
 833         cctx->term = buffer_get_string(&m, &len);
 834
 835         cmd = buffer_get_string(&m, &len);
 836         buffer_init(&cctx->cmd);
 837         buffer_append(&cctx->cmd, cmd, strlen(cmd));
 838
 839         env_len = buffer_get_int(&m);
 840         env_len = MIN(env_len, 4096);
 841         debug3("%s: receiving %d env vars", __func__, env_len);
 842         if (env_len != 0) {
 843                 cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env));
 844                 for (i = 0; i < env_len; i++)
 845                         cctx->env[i] = buffer_get_string(&m, &len);
 846                 cctx->env[i] = NULL;
 847         }
 848
 849         debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__,
 850             cctx->want_tty, cctx->want_subsys, cmd);
 851         xfree(cmd);
 852
 853         /* Gather fds from client */
 854         new_fd[0] = mm_receive_fd(client_fd);
 855         new_fd[1] = mm_receive_fd(client_fd);
 856         new_fd[2] = mm_receive_fd(client_fd);
 857
 858         debug2("%s: got fds stdin %d, stdout %d, stderr %d", __func__,
 859             new_fd[0], new_fd[1], new_fd[2]);
 860
 861         /* Try to pick up ttymodes from client before it goes raw */
 862         if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1)
 863                 error("%s: tcgetattr: %s", __func__, strerror(errno));
 864
 865         /* This roundtrip is just for synchronisation of ttymodes */
 866         buffer_clear(&m);
 867         if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 868                 error("%s: client msg_send failed", __func__);
 869                 close(client_fd);
 870                 close(new_fd[0]);
 871                 close(new_fd[1]);
 872                 close(new_fd[2]);
 873                 buffer_free(&m);
 874                 xfree(cctx->term);
 875                 if (env_len != 0) {
 876                         for (i = 0; i < env_len; i++)
 877                                 xfree(cctx->env[i]);
 878                         xfree(cctx->env);
 879                 }
 880                 return;
 881         }
 882         buffer_free(&m);
 883
 884         /* enable nonblocking unless tty */
 885         if (!isatty(new_fd[0]))
 886                 set_nonblock(new_fd[0]);
 887         if (!isatty(new_fd[1]))
 888                 set_nonblock(new_fd[1]);
 889         if (!isatty(new_fd[2]))
 890                 set_nonblock(new_fd[2]);
 891
 892         set_nonblock(client_fd);
 893
 894         c = channel_new("session", SSH_CHANNEL_OPENING,
 895             new_fd[0], new_fd[1], new_fd[2],
 896             CHAN_SES_WINDOW_DEFAULT, CHAN_SES_PACKET_DEFAULT,
 897             CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0);
 898
 899         /* XXX */
 900         c->ctl_fd = client_fd;
 901
 902         debug3("%s: channel_new: %d", __func__, c->self);
 903
 904         channel_send_open(c->self);
 905         channel_register_confirm(c->self, client_extra_session2_setup, cctx);
 906 }
 907
 908 static void
 909 process_cmdline(void)
 910 {
 911         void (*handler)(int);
 912         char *s, *cmd, *cancel_host;
 913         int delete = 0;
 914         int local = 0;
 915         u_short cancel_port;
 916         Forward fwd;
 917
 918         leave_raw_mode();
 919         handler = signal(SIGINT, SIG_IGN);
 920         cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
 921         if (s == NULL)
 922                 goto out;
 923         while (*s && isspace(*s))
 924                 s++;
 925         if (*s == '-')
 926                 s++;    /* Skip cmdline '-', if any */
 927         if (*s == '\0')
 928                 goto out;
 929
 930         if (*s == 'h' || *s == 'H' || *s == '?') {
 931                 logit("Commands:");
 932                 logit("      -L[bind_address:]port:host:hostport    "
 933                     "Request local forward");
 934                 logit("      -R[bind_address:]port:host:hostport    "
 935                     "Request remote forward");
 936                 logit("      -KR[bind_address:]port                 "
 937                     "Cancel remote forward");
 938                 if (!options.permit_local_command)
 939                         goto out;
 940                 logit("      !args                                  "
 941                     "Execute local command");
 942                 goto out;
 943         }
 944
 945         if (*s == '!' && options.permit_local_command) {
 946                 s++;
 947                 ssh_local_cmd(s);
 948                 goto out;
 949         }
 950
 951         if (*s == 'K') {
 952                 delete = 1;
 953                 s++;
 954         }
 955         if (*s != 'L' && *s != 'R') {
 956                 logit("Invalid command.");
 957                 goto out;
 958         }
 959         if (*s == 'L')
 960                 local = 1;
 961         if (local && delete) {
 962                 logit("Not supported.");
 963                 goto out;
 964         }
 965         if ((!local || delete) && !compat20) {
 966                 logit("Not supported for SSH protocol version 1.");
 967                 goto out;
 968         }
 969
 970         s++;
 971         while (*s && isspace(*s))
 972                 s++;
 973
 974         if (delete) {
 975                 cancel_port = 0;
 976                 cancel_host = hpdelim(&s);      /* may be NULL */
 977                 if (s != NULL) {
 978                         cancel_port = a2port(s);
 979                         cancel_host = cleanhostname(cancel_host);
 980                 } else {
 981                         cancel_port = a2port(cancel_host);
 982                         cancel_host = NULL;
 983                 }
 984                 if (cancel_port == 0) {
 985                         logit("Bad forwarding close port");
 986                         goto out;
 987                 }
 988                 channel_request_rforward_cancel(cancel_host, cancel_port);
 989         } else {
 990                 if (!parse_forward(&fwd, s)) {
 991                         logit("Bad forwarding specification.");
 992                         goto out;
 993                 }
 994                 if (local) {
 995                         if (channel_setup_local_fwd_listener(fwd.listen_host,
 996                             fwd.listen_port, fwd.connect_host,
 997                             fwd.connect_port, options.gateway_ports) < 0) {
 998                                 logit("Port forwarding failed.");
 999                                 goto out;
1000                         }
1001                 } else {
1002                         if (channel_request_remote_forwarding(fwd.listen_host,
1003                             fwd.listen_port, fwd.connect_host,
1004                             fwd.connect_port) < 0) {
1005                                 logit("Port forwarding failed.");
1006                                 goto out;
1007                         }
1008                 }
1009
1010                 logit("Forwarding port.");
1011         }
1012
1013 out:
1014         signal(SIGINT, handler);
1015         enter_raw_mode();
1016         if (cmd)
1017                 xfree(cmd);
1018 }
1019
1020 /* process the characters one by one */
1021 static int
1022 process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
1023 {
1024         char string[1024];
1025         pid_t pid;
1026         int bytes = 0;
1027         u_int i;
1028         u_char ch;
1029         char *s;
1030
1031         if (len <= 0)
1032                 return (0);
1033
1034         for (i = 0; i < (u_int)len; i++) {
1035                 /* Get one character at a time. */
1036                 ch = buf[i];
1037
1038                 if (escape_pending) {
1039                         /* We have previously seen an escape character. */
1040                         /* Clear the flag now. */
1041                         escape_pending = 0;
1042
1043                         /* Process the escaped character. */
1044                         switch (ch) {
1045                         case '.':
1046                                 /* Terminate the connection. */
1047                                 snprintf(string, sizeof string, "%c.\r\n", escape_char);
1048                                 buffer_append(berr, string, strlen(string));
1049
1050                                 quit_pending = 1;
1051                                 return -1;
1052
1053                         case 'Z' - 64:
1054                                 /* Suspend the program. */
1055                                 /* Print a message to that effect to the user. */
1056                                 snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
1057                                 buffer_append(berr, string, strlen(string));
1058
1059                                 /* Restore terminal modes and suspend. */
1060                                 client_suspend_self(bin, bout, berr);
1061
1062                                 /* We have been continued. */
1063                                 continue;
1064
1065                         case 'B':
1066                                 if (compat20) {
1067                                         snprintf(string, sizeof string,
1068                                             "%cB\r\n", escape_char);
1069                                         buffer_append(berr, string,
1070                                             strlen(string));
1071                                         channel_request_start(session_ident,
1072                                             "break", 0);
1073                                         packet_put_int(1000);
1074                                         packet_send();
1075                                 }
1076                                 continue;
1077
1078                         case 'R':
1079                                 if (compat20) {
1080                                         if (datafellows & SSH_BUG_NOREKEY)
1081                                                 logit("Server does not support re-keying");
1082                                         else
1083                                                 need_rekeying = 1;
1084                                 }
1085                                 continue;
1086
1087                         case '&':
1088                                 /*
1089                                  * Detach the program (continue to serve connections,
1090                                  * but put in background and no more new connections).
1091                                  */
1092                                 /* Restore tty modes. */
1093                                 leave_raw_mode();
1094
1095                                 /* Stop listening for new connections. */
1096                                 channel_stop_listening();
1097
1098                                 snprintf(string, sizeof string,
1099                                     "%c& [backgrounded]\n", escape_char);
1100                                 buffer_append(berr, string, strlen(string));
1101
1102                                 /* Fork into background. */
1103                                 pid = fork();
1104                                 if (pid < 0) {
1105                                         error("fork: %.100s", strerror(errno));
1106                                         continue;
1107                                 }
1108                                 if (pid != 0) { /* This is the parent. */
1109                                         /* The parent just exits. */
1110                                         exit(0);
1111                                 }
1112                                 /* The child continues serving connections. */
1113                                 if (compat20) {
1114                                         buffer_append(bin, "\004", 1);
1115                                         /* fake EOF on stdin */
1116                                         return -1;
1117                                 } else if (!stdin_eof) {
1118                                         /*
1119                                          * Sending SSH_CMSG_EOF alone does not always appear
1120                                          * to be enough.  So we try to send an EOF character
1121                                          * first.
1122                                          */
1123                                         packet_start(SSH_CMSG_STDIN_DATA);
1124                                         packet_put_string("\004", 1);
1125                                         packet_send();
1126                                         /* Close stdin. */
1127                                         stdin_eof = 1;
1128                                         if (buffer_len(bin) == 0) {
1129                                                 packet_start(SSH_CMSG_EOF);
1130                                                 packet_send();
1131                                         }
1132                                 }
1133                                 continue;
1134
1135                         case '?':
1136                                 snprintf(string, sizeof string,
1137 "%c?\r\n\
1138 Supported escape sequences:\r\n\
1139 %c.  - terminate connection\r\n\
1140 %cB  - send a BREAK to the remote system\r\n\
1141 %cC  - open a command line\r\n\
1142 %cR  - Request rekey (SSH protocol 2 only)\r\n\
1143 %c^Z - suspend ssh\r\n\
1144 %c#  - list forwarded connections\r\n\
1145 %c&  - background ssh (when waiting for connections to terminate)\r\n\
1146 %c?  - this message\r\n\
1147 %c%c  - send the escape character by typing it twice\r\n\
1148 (Note that escapes are only recognized immediately after newline.)\r\n",
1149                                     escape_char, escape_char, escape_char, escape_char,
1150                                     escape_char, escape_char, escape_char, escape_char,
1151                                     escape_char, escape_char, escape_char);
1152                                 buffer_append(berr, string, strlen(string));
1153                                 continue;
1154
1155                         case '#':
1156                                 snprintf(string, sizeof string, "%c#\r\n", escape_char);
1157                                 buffer_append(berr, string, strlen(string));
1158                                 s = channel_open_message();
1159                                 buffer_append(berr, s, strlen(s));
1160                                 xfree(s);
1161                                 continue;
1162
1163                         case 'C':
1164                                 process_cmdline();
1165                                 continue;
1166
1167                         default:
1168                                 if (ch != escape_char) {
1169                                         buffer_put_char(bin, escape_char);
1170                                         bytes++;
1171                                 }
1172                                 /* Escaped characters fall through here */
1173                                 break;
1174                         }
1175                 } else {
1176                         /*
1177                          * The previous character was not an escape char. Check if this
1178                          * is an escape.
1179                          */
1180                         if (last_was_cr && ch == escape_char) {
1181                                 /* It is. Set the flag and continue to next character. */
1182                                 escape_pending = 1;
1183                                 continue;
1184                         }
1185                 }
1186
1187                 /*
1188                  * Normal character.  Record whether it was a newline,
1189                  * and append it to the buffer.
1190                  */
1191                 last_was_cr = (ch == '\r' || ch == '\n');
1192                 buffer_put_char(bin, ch);
1193                 bytes++;
1194         }
1195         return bytes;
1196 }
1197
1198 static void
1199 client_process_input(fd_set *readset)
1200 {
1201         int len;
1202         char buf[8192];
1203
1204         /* Read input from stdin. */
1205         if (FD_ISSET(fileno(stdin), readset)) {
1206                 /* Read as much as possible. */
1207                 len = read(fileno(stdin), buf, sizeof(buf));
1208                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
1209                         return;         /* we'll try again later */
1210                 if (len <= 0) {
1211                         /*
1212                          * Received EOF or error.  They are treated
1213                          * similarly, except that an error message is printed
1214                          * if it was an error condition.
1215                          */
1216                         if (len < 0) {
1217                                 snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
1218                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1219                         }
1220                         /* Mark that we have seen EOF. */
1221                         stdin_eof = 1;
1222                         /*
1223                          * Send an EOF message to the server unless there is
1224                          * data in the buffer.  If there is data in the
1225                          * buffer, no message will be sent now.  Code
1226                          * elsewhere will send the EOF when the buffer
1227                          * becomes empty if stdin_eof is set.
1228                          */
1229                         if (buffer_len(&stdin_buffer) == 0) {
1230                                 packet_start(SSH_CMSG_EOF);
1231                                 packet_send();
1232                         }
1233                 } else if (escape_char == SSH_ESCAPECHAR_NONE) {
1234                         /*
1235                          * Normal successful read, and no escape character.
1236                          * Just append the data to buffer.
1237                          */
1238                         buffer_append(&stdin_buffer, buf, len);
1239                 } else {
1240                         /*
1241                          * Normal, successful read.  But we have an escape character
1242                          * and have to process the characters one by one.
1243                          */
1244                         if (process_escapes(&stdin_buffer, &stdout_buffer,
1245                             &stderr_buffer, buf, len) == -1)
1246                                 return;
1247                 }
1248         }
1249 }
1250
1251 static void
1252 client_process_output(fd_set *writeset)
1253 {
1254         int len;
1255         char buf[100];
1256
1257         /* Write buffered output to stdout. */
1258         if (FD_ISSET(fileno(stdout), writeset)) {
1259                 /* Write as much data as possible. */
1260                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1261                     buffer_len(&stdout_buffer));
1262                 if (len <= 0) {
1263                         if (errno == EINTR || errno == EAGAIN)
1264                                 len = 0;
1265                         else {
1266                                 /*
1267                                  * An error or EOF was encountered.  Put an
1268                                  * error message to stderr buffer.
1269                                  */
1270                                 snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
1271                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1272                                 quit_pending = 1;
1273                                 return;
1274                         }
1275                 }
1276                 /* Consume printed data from the buffer. */
1277                 buffer_consume(&stdout_buffer, len);
1278                 stdout_bytes += len;
1279         }
1280         /* Write buffered output to stderr. */
1281         if (FD_ISSET(fileno(stderr), writeset)) {
1282                 /* Write as much data as possible. */
1283                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1284                     buffer_len(&stderr_buffer));
1285                 if (len <= 0) {
1286                         if (errno == EINTR || errno == EAGAIN)
1287                                 len = 0;
1288                         else {
1289                                 /* EOF or error, but can't even print error message. */
1290                                 quit_pending = 1;
1291                                 return;
1292                         }
1293                 }
1294                 /* Consume printed characters from the buffer. */
1295                 buffer_consume(&stderr_buffer, len);
1296                 stderr_bytes += len;
1297         }
1298 }
1299
1300 /*
1301  * Get packets from the connection input buffer, and process them as long as
1302  * there are packets available.
1303  *
1304  * Any unknown packets received during the actual
1305  * session cause the session to terminate.  This is
1306  * intended to make debugging easier since no
1307  * confirmations are sent.  Any compatible protocol
1308  * extensions must be negotiated during the
1309  * preparatory phase.
1310  */
1311
1312 static void
1313 client_process_buffered_input_packets(void)
1314 {
1315         dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL);
1316 }
1317
1318 /* scan buf[] for '~' before sending data to the peer */
1319
1320 static int
1321 simple_escape_filter(Channel *c, char *buf, int len)
1322 {
1323         /* XXX we assume c->extended is writeable */
1324         return process_escapes(&c->input, &c->output, &c->extended, buf, len);
1325 }
1326
1327 static void
1328 client_channel_closed(int id, void *arg)
1329 {
1330         channel_cancel_cleanup(id);
1331         session_closed = 1;
1332         leave_raw_mode();
1333 }
1334
1335 /*
1336  * Implements the interactive session with the server.  This is called after
1337  * the user has been authenticated, and a command has been started on the
1338  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1339  * used as an escape character for terminating or suspending the session.
1340  */
1341
1342 int
1343 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1344 {
1345         fd_set *readset = NULL, *writeset = NULL;
1346         double start_time, total_time;
1347         int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1348         u_int nalloc = 0;
1349         char buf[100];
1350
1351         debug("Entering interactive session.");
1352
1353         start_time = get_current_time();
1354
1355         /* Initialize variables. */
1356         escape_pending = 0;
1357         last_was_cr = 1;
1358         exit_status = -1;
1359         stdin_eof = 0;
1360         buffer_high = 64 * 1024;
1361         connection_in = packet_get_connection_in();
1362         connection_out = packet_get_connection_out();
1363         max_fd = MAX(connection_in, connection_out);
1364         if (control_fd != -1)
1365                 max_fd = MAX(max_fd, control_fd);
1366
1367         if (!compat20) {
1368                 /* enable nonblocking unless tty */
1369                 if (!isatty(fileno(stdin)))
1370                         set_nonblock(fileno(stdin));
1371                 if (!isatty(fileno(stdout)))
1372                         set_nonblock(fileno(stdout));
1373                 if (!isatty(fileno(stderr)))
1374                         set_nonblock(fileno(stderr));
1375                 max_fd = MAX(max_fd, fileno(stdin));
1376                 max_fd = MAX(max_fd, fileno(stdout));
1377                 max_fd = MAX(max_fd, fileno(stderr));
1378         }
1379         stdin_bytes = 0;
1380         stdout_bytes = 0;
1381         stderr_bytes = 0;
1382         quit_pending = 0;
1383         escape_char = escape_char_arg;
1384
1385         /* Initialize buffers. */
1386         buffer_init(&stdin_buffer);
1387         buffer_init(&stdout_buffer);
1388         buffer_init(&stderr_buffer);
1389
1390         client_init_dispatch();
1391
1392         /*
1393          * Set signal handlers, (e.g. to restore non-blocking mode)
1394          * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1395          */
1396         if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1397                 signal(SIGHUP, signal_handler);
1398         if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1399                 signal(SIGINT, signal_handler);
1400         if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1401                 signal(SIGQUIT, signal_handler);
1402         if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1403                 signal(SIGTERM, signal_handler);
1404         signal(SIGWINCH, window_change_handler);
1405
1406         if (have_pty)
1407                 enter_raw_mode();
1408
1409         if (compat20) {
1410                 session_ident = ssh2_chan_id;
1411                 if (escape_char != SSH_ESCAPECHAR_NONE)
1412                         channel_register_filter(session_ident,
1413                             simple_escape_filter, NULL);
1414                 if (session_ident != -1)
1415                         channel_register_cleanup(session_ident,
1416                             client_channel_closed, 0);
1417         } else {
1418                 /* Check if we should immediately send eof on stdin. */
1419                 client_check_initial_eof_on_stdin();
1420         }
1421
1422         /* Main loop of the client for the interactive session mode. */
1423         while (!quit_pending) {
1424
1425                 /* Process buffered packets sent by the server. */
1426                 client_process_buffered_input_packets();
1427
1428                 if (compat20 && session_closed && !channel_still_open())
1429                         break;
1430
1431                 rekeying = (xxx_kex != NULL && !xxx_kex->done);
1432
1433                 if (rekeying) {
1434                         debug("rekeying in progress");
1435                 } else {
1436                         /*
1437                          * Make packets of buffered stdin data, and buffer
1438                          * them for sending to the server.
1439                          */
1440                         if (!compat20)
1441                                 client_make_packets_from_stdin_data();
1442
1443                         /*
1444                          * Make packets from buffered channel data, and
1445                          * enqueue them for sending to the server.
1446                          */
1447                         if (packet_not_very_much_data_to_write())
1448                                 channel_output_poll();
1449
1450                         /*
1451                          * Check if the window size has changed, and buffer a
1452                          * message about it to the server if so.
1453                          */
1454                         client_check_window_change();
1455
1456                         if (quit_pending)
1457                                 break;
1458                 }
1459                 /*
1460                  * Wait until we have something to do (something becomes
1461                  * available on one of the descriptors).
1462                  */
1463                 max_fd2 = max_fd;
1464                 client_wait_until_can_do_something(&readset, &writeset,
1465                     &max_fd2, &nalloc, rekeying);
1466
1467                 if (quit_pending)
1468                         break;
1469
1470                 /* Do channel operations unless rekeying in progress. */
1471                 if (!rekeying) {
1472                         channel_after_select(readset, writeset);
1473                         if (need_rekeying || packet_need_rekeying()) {
1474                                 debug("need rekeying");
1475                                 xxx_kex->done = 0;
1476                                 kex_send_kexinit(xxx_kex);
1477                                 need_rekeying = 0;
1478                         }
1479                 }
1480
1481                 /* Buffer input from the connection.  */
1482                 client_process_net_input(readset);
1483
1484                 /* Accept control connections.  */
1485                 client_process_control(readset);
1486
1487                 if (quit_pending)
1488                         break;
1489
1490                 if (!compat20) {
1491                         /* Buffer data from stdin */
1492                         client_process_input(readset);
1493                         /*
1494                          * Process output to stdout and stderr.  Output to
1495                          * the connection is processed elsewhere (above).
1496                          */
1497                         client_process_output(writeset);
1498                 }
1499
1500                 /* Send as much buffered packet data as possible to the sender. */
1501                 if (FD_ISSET(connection_out, writeset))
1502                         packet_write_poll();
1503         }
1504         if (readset)
1505                 xfree(readset);
1506         if (writeset)
1507                 xfree(writeset);
1508
1509         /* Terminate the session. */
1510
1511         /* Stop watching for window change. */
1512         signal(SIGWINCH, SIG_DFL);
1513
1514         channel_free_all();
1515
1516         if (have_pty)
1517                 leave_raw_mode();
1518
1519         /* restore blocking io */
1520         if (!isatty(fileno(stdin)))
1521                 unset_nonblock(fileno(stdin));
1522         if (!isatty(fileno(stdout)))
1523                 unset_nonblock(fileno(stdout));
1524         if (!isatty(fileno(stderr)))
1525                 unset_nonblock(fileno(stderr));
1526
1527         /*
1528          * If there was no shell or command requested, there will be no remote
1529          * exit status to be returned.  In that case, clear error code if the
1530          * connection was deliberately terminated at this end.
1531          */
1532         if (no_shell_flag && received_signal == SIGTERM) {
1533                 received_signal = 0;
1534                 exit_status = 0;
1535         }
1536
1537         if (received_signal)
1538                 fatal("Killed by signal %d.", (int) received_signal);
1539
1540         /*
1541          * In interactive mode (with pseudo tty) display a message indicating
1542          * that the connection has been closed.
1543          */
1544         if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1545                 snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
1546                 buffer_append(&stderr_buffer, buf, strlen(buf));
1547         }
1548
1549         /* Output any buffered data for stdout. */
1550         while (buffer_len(&stdout_buffer) > 0) {
1551                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1552                     buffer_len(&stdout_buffer));
1553                 if (len <= 0) {
1554                         error("Write failed flushing stdout buffer.");
1555                         break;
1556                 }
1557                 buffer_consume(&stdout_buffer, len);
1558                 stdout_bytes += len;
1559         }
1560
1561         /* Output any buffered data for stderr. */
1562         while (buffer_len(&stderr_buffer) > 0) {
1563                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1564                     buffer_len(&stderr_buffer));
1565                 if (len <= 0) {
1566                         error("Write failed flushing stderr buffer.");
1567                         break;
1568                 }
1569                 buffer_consume(&stderr_buffer, len);
1570                 stderr_bytes += len;
1571         }
1572
1573         /* Clear and free any buffers. */
1574         memset(buf, 0, sizeof(buf));
1575         buffer_free(&stdin_buffer);
1576         buffer_free(&stdout_buffer);
1577         buffer_free(&stderr_buffer);
1578
1579         /* Report bytes transferred, and transfer rates. */
1580         total_time = get_current_time() - start_time;
1581         debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
1582             stdin_bytes, stdout_bytes, stderr_bytes, total_time);
1583         if (total_time > 0)
1584                 debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
1585                     stdin_bytes / total_time, stdout_bytes / total_time,
1586                     stderr_bytes / total_time);
1587
1588         /* Return the exit status of the program. */
1589         debug("Exit status %d", exit_status);
1590         return exit_status;
1591 }
1592
1593 /*********/
1594
1595 static void
1596 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1597 {
1598         u_int data_len;
1599         char *data = packet_get_string(&data_len);
1600         packet_check_eom();
1601         buffer_append(&stdout_buffer, data, data_len);
1602         memset(data, 0, data_len);
1603         xfree(data);
1604 }
1605 static void
1606 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1607 {
1608         u_int data_len;
1609         char *data = packet_get_string(&data_len);
1610         packet_check_eom();
1611         buffer_append(&stderr_buffer, data, data_len);
1612         memset(data, 0, data_len);
1613         xfree(data);
1614 }
1615 static void
1616 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1617 {
1618         exit_status = packet_get_int();
1619         packet_check_eom();
1620         /* Acknowledge the exit. */
1621         packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1622         packet_send();
1623         /*
1624          * Must wait for packet to be sent since we are
1625          * exiting the loop.
1626          */
1627         packet_write_wait();
1628         /* Flag that we want to exit. */
1629         quit_pending = 1;
1630 }
1631 static void
1632 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1633 {
1634         Channel *c = NULL;
1635         int remote_id, sock;
1636
1637         /* Read the remote channel number from the message. */
1638         remote_id = packet_get_int();
1639         packet_check_eom();
1640
1641         /*
1642          * Get a connection to the local authentication agent (this may again
1643          * get forwarded).
1644          */
1645         sock = ssh_get_authentication_socket();
1646
1647         /*
1648          * If we could not connect the agent, send an error message back to
1649          * the server. This should never happen unless the agent dies,
1650          * because authentication forwarding is only enabled if we have an
1651          * agent.
1652          */
1653         if (sock >= 0) {
1654                 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1655                     -1, 0, 0, 0, "authentication agent connection", 1);
1656                 c->remote_id = remote_id;
1657                 c->force_drain = 1;
1658         }
1659         if (c == NULL) {
1660                 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1661                 packet_put_int(remote_id);
1662         } else {
1663                 /* Send a confirmation to the remote host. */
1664                 debug("Forwarding authentication connection.");
1665                 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1666                 packet_put_int(remote_id);
1667                 packet_put_int(c->self);
1668         }
1669         packet_send();
1670 }
1671
1672 static Channel *
1673 client_request_forwarded_tcpip(const char *request_type, int rchan)
1674 {
1675         Channel *c = NULL;
1676         char *listen_address, *originator_address;
1677         int listen_port, originator_port;
1678         int sock;
1679
1680         /* Get rest of the packet */
1681         listen_address = packet_get_string(NULL);
1682         listen_port = packet_get_int();
1683         originator_address = packet_get_string(NULL);
1684         originator_port = packet_get_int();
1685         packet_check_eom();
1686
1687         debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1688             listen_address, listen_port, originator_address, originator_port);
1689
1690         sock = channel_connect_by_listen_address(listen_port);
1691         if (sock < 0) {
1692                 xfree(originator_address);
1693                 xfree(listen_address);
1694                 return NULL;
1695         }
1696         c = channel_new("forwarded-tcpip",
1697             SSH_CHANNEL_CONNECTING, sock, sock, -1,
1698             CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1699             originator_address, 1);
1700         xfree(originator_address);
1701         xfree(listen_address);
1702         return c;
1703 }
1704
1705 static Channel *
1706 client_request_x11(const char *request_type, int rchan)
1707 {
1708         Channel *c = NULL;
1709         char *originator;
1710         int originator_port;
1711         int sock;
1712
1713         if (!options.forward_x11) {
1714                 error("Warning: ssh server tried X11 forwarding.");
1715                 error("Warning: this is probably a break-in attempt by a malicious server.");
1716                 return NULL;
1717         }
1718         originator = packet_get_string(NULL);
1719         if (datafellows & SSH_BUG_X11FWD) {
1720                 debug2("buggy server: x11 request w/o originator_port");
1721                 originator_port = 0;
1722         } else {
1723                 originator_port = packet_get_int();
1724         }
1725         packet_check_eom();
1726         /* XXX check permission */
1727         debug("client_request_x11: request from %s %d", originator,
1728             originator_port);
1729         xfree(originator);
1730         sock = x11_connect_display();
1731         if (sock < 0)
1732                 return NULL;
1733         c = channel_new("x11",
1734             SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1735             CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1736         c->force_drain = 1;
1737         return c;
1738 }
1739
1740 static Channel *
1741 client_request_agent(const char *request_type, int rchan)
1742 {
1743         Channel *c = NULL;
1744         int sock;
1745
1746         if (!options.forward_agent) {
1747                 error("Warning: ssh server tried agent forwarding.");
1748                 error("Warning: this is probably a break-in attempt by a malicious server.");
1749                 return NULL;
1750         }
1751         sock =  ssh_get_authentication_socket();
1752         if (sock < 0)
1753                 return NULL;
1754         c = channel_new("authentication agent connection",
1755             SSH_CHANNEL_OPEN, sock, sock, -1,
1756             CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1757             "authentication agent connection", 1);
1758         c->force_drain = 1;
1759         return c;
1760 }
1761
1762 /* XXXX move to generic input handler */
1763 static void
1764 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1765 {
1766         Channel *c = NULL;
1767         char *ctype;
1768         int rchan;
1769         u_int rmaxpack, rwindow, len;
1770
1771         ctype = packet_get_string(&len);
1772         rchan = packet_get_int();
1773         rwindow = packet_get_int();
1774         rmaxpack = packet_get_int();
1775
1776         debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1777             ctype, rchan, rwindow, rmaxpack);
1778
1779         if (strcmp(ctype, "forwarded-tcpip") == 0) {
1780                 c = client_request_forwarded_tcpip(ctype, rchan);
1781         } else if (strcmp(ctype, "x11") == 0) {
1782                 c = client_request_x11(ctype, rchan);
1783         } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1784                 c = client_request_agent(ctype, rchan);
1785         }
1786 /* XXX duplicate : */
1787         if (c != NULL) {
1788                 debug("confirm %s", ctype);
1789                 c->remote_id = rchan;
1790                 c->remote_window = rwindow;
1791                 c->remote_maxpacket = rmaxpack;
1792                 if (c->type != SSH_CHANNEL_CONNECTING) {
1793                         packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1794                         packet_put_int(c->remote_id);
1795                         packet_put_int(c->self);
1796                         packet_put_int(c->local_window);
1797                         packet_put_int(c->local_maxpacket);
1798                         packet_send();
1799                 }
1800         } else {
1801                 debug("failure %s", ctype);
1802                 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1803                 packet_put_int(rchan);
1804                 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1805                 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1806                         packet_put_cstring("open failed");
1807                         packet_put_cstring("");
1808                 }
1809                 packet_send();
1810         }
1811         xfree(ctype);
1812 }
1813 static void
1814 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1815 {
1816         Channel *c = NULL;
1817         int exitval, id, reply, success = 0;
1818         char *rtype;
1819
1820         id = packet_get_int();
1821         rtype = packet_get_string(NULL);
1822         reply = packet_get_char();
1823
1824         debug("client_input_channel_req: channel %d rtype %s reply %d",
1825             id, rtype, reply);
1826
1827         if (id == -1) {
1828                 error("client_input_channel_req: request for channel -1");
1829         } else if ((c = channel_lookup(id)) == NULL) {
1830                 error("client_input_channel_req: channel %d: unknown channel", id);
1831         } else if (strcmp(rtype, "exit-status") == 0) {
1832                 exitval = packet_get_int();
1833                 if (id == session_ident) {
1834                         success = 1;
1835                         exit_status = exitval;
1836                 } else if (c->ctl_fd == -1) {
1837                         error("client_input_channel_req: unexpected channel %d",
1838                             session_ident);
1839                 } else {
1840                         atomicio(vwrite, c->ctl_fd, &exitval, sizeof(exitval));
1841                         success = 1;
1842                 }
1843                 packet_check_eom();
1844         }
1845         if (reply) {
1846                 packet_start(success ?
1847                     SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1848                 packet_put_int(id);
1849                 packet_send();
1850         }
1851         xfree(rtype);
1852 }
1853 static void
1854 client_input_global_request(int type, u_int32_t seq, void *ctxt)
1855 {
1856         char *rtype;
1857         int want_reply;
1858         int success = 0;
1859
1860         rtype = packet_get_string(NULL);
1861         want_reply = packet_get_char();
1862         debug("client_input_global_request: rtype %s want_reply %d",
1863             rtype, want_reply);
1864         if (want_reply) {
1865                 packet_start(success ?
1866                     SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1867                 packet_send();
1868                 packet_write_wait();
1869         }
1870         xfree(rtype);
1871 }
1872
1873 void
1874 client_session2_setup(int id, int want_tty, int want_subsystem,
1875     const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env,
1876     dispatch_fn *subsys_repl)
1877 {
1878         int len;
1879         Channel *c = NULL;
1880
1881         debug2("%s: id %d", __func__, id);
1882
1883         if ((c = channel_lookup(id)) == NULL)
1884                 fatal("client_session2_setup: channel %d: unknown channel", id);
1885
1886         if (want_tty) {
1887                 struct winsize ws;
1888                 struct termios tio;
1889
1890                 /* Store window size in the packet. */
1891                 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
1892                         memset(&ws, 0, sizeof(ws));
1893
1894                 channel_request_start(id, "pty-req", 0);
1895                 packet_put_cstring(term != NULL ? term : "");
1896                 packet_put_int((u_int)ws.ws_col);
1897                 packet_put_int((u_int)ws.ws_row);
1898                 packet_put_int((u_int)ws.ws_xpixel);
1899                 packet_put_int((u_int)ws.ws_ypixel);
1900                 tio = get_saved_tio();
1901                 tty_make_modes(-1, tiop != NULL ? tiop : &tio);
1902                 packet_send();
1903                 /* XXX wait for reply */
1904                 c->client_tty = 1;
1905         }
1906
1907         /* Transfer any environment variables from client to server */
1908         if (options.num_send_env != 0 && env != NULL) {
1909                 int i, j, matched;
1910                 char *name, *val;
1911
1912                 debug("Sending environment.");
1913                 for (i = 0; env[i] != NULL; i++) {
1914                         /* Split */
1915                         name = xstrdup(env[i]);
1916                         if ((val = strchr(name, '=')) == NULL) {
1917                                 xfree(name);
1918                                 continue;
1919                         }
1920                         *val++ = '\0';
1921
1922                         matched = 0;
1923                         for (j = 0; j < options.num_send_env; j++) {
1924                                 if (match_pattern(name, options.send_env[j])) {
1925                                         matched = 1;
1926                                         break;
1927                                 }
1928                         }
1929                         if (!matched) {
1930                                 debug3("Ignored env %s", name);
1931                                 xfree(name);
1932                                 continue;
1933                         }
1934
1935                         debug("Sending env %s = %s", name, val);
1936                         channel_request_start(id, "env", 0);
1937                         packet_put_cstring(name);
1938                         packet_put_cstring(val);
1939                         packet_send();
1940                         xfree(name);
1941                 }
1942         }
1943
1944         len = buffer_len(cmd);
1945         if (len > 0) {
1946                 if (len > 900)
1947                         len = 900;
1948                 if (want_subsystem) {
1949                         debug("Sending subsystem: %.*s", len, (u_char*)buffer_ptr(cmd));
1950                         channel_request_start(id, "subsystem", subsys_repl != NULL);
1951                         if (subsys_repl != NULL) {
1952                                 /* register callback for reply */
1953                                 /* XXX we assume that client_loop has already been called */
1954                                 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, subsys_repl);
1955                                 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, subsys_repl);
1956                         }
1957                 } else {
1958                         debug("Sending command: %.*s", len, (u_char*)buffer_ptr(cmd));
1959                         channel_request_start(id, "exec", 0);
1960                 }
1961                 packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
1962                 packet_send();
1963         } else {
1964                 channel_request_start(id, "shell", 0);
1965                 packet_send();
1966         }
1967 }
1968
1969 static void
1970 client_init_dispatch_20(void)
1971 {
1972         dispatch_init(&dispatch_protocol_error);
1973
1974         dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1975         dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1976         dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1977         dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1978         dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1979         dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1980         dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1981         dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1982         dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1983         dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1984
1985         /* rekeying */
1986         dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1987
1988         /* global request reply messages */
1989         dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
1990         dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1991 }
1992 static void
1993 client_init_dispatch_13(void)
1994 {
1995         dispatch_init(NULL);
1996         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1997         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1998         dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1999         dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2000         dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2001         dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2002         dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2003         dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2004         dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
2005
2006         dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
2007             &client_input_agent_open : &deny_input_open);
2008         dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2009             &x11_input_open : &deny_input_open);
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 static void
2019 client_init_dispatch(void)
2020 {
2021         if (compat20)
2022                 client_init_dispatch_20();
2023         else if (compat13)
2024                 client_init_dispatch_13();
2025         else
2026                 client_init_dispatch_15();
2027 }
2028
2029 /* client specific fatal cleanup */
2030 void
2031 cleanup_exit(int i)
2032 {
2033         leave_raw_mode();
2034         leave_non_blocking();
2035         if (options.control_path != NULL && control_fd != -1)
2036                 unlink(options.control_path);
2037         _exit(i);
2038 }