clientloop.c

   1 /* $OpenBSD: clientloop.c,v 1.169 2006/07/17 01:31:09 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 <termios.h>
  78 #include <unistd.h>
  79
  80 #include "ssh.h"
  81 #include "ssh1.h"
  82 #include "ssh2.h"
  83 #include "xmalloc.h"
  84 #include "packet.h"
  85 #include "buffer.h"
  86 #include "compat.h"
  87 #include "channels.h"
  88 #include "dispatch.h"
  89 #include "buffer.h"
  90 #include "bufaux.h"
  91 #include "key.h"
  92 #include "kex.h"
  93 #include "log.h"
  94 #include "readconf.h"
  95 #include "clientloop.h"
  96 #include "sshconnect.h"
  97 #include "authfd.h"
  98 #include "atomicio.h"
  99 #include "sshpty.h"
 100 #include "misc.h"
 101 #include "monitor_fdpass.h"
 102 #include "match.h"
 103 #include "msg.h"
 104
 105 /* import options */
 106 extern Options options;
 107
 108 /* Flag indicating that stdin should be redirected from /dev/null. */
 109 extern int stdin_null_flag;
 110
 111 /* Flag indicating that no shell has been requested */
 112 extern int no_shell_flag;
 113
 114 /* Control socket */
 115 extern int control_fd;
 116
 117 /*
 118  * Name of the host we are connecting to.  This is the name given on the
 119  * command line, or the HostName specified for the user-supplied name in a
 120  * configuration file.
 121  */
 122 extern char *host;
 123
 124 /*
 125  * Flag to indicate that we have received a window change signal which has
 126  * not yet been processed.  This will cause a message indicating the new
 127  * window size to be sent to the server a little later.  This is volatile
 128  * because this is updated in a signal handler.
 129  */
 130 static volatile sig_atomic_t received_window_change_signal = 0;
 131 static volatile sig_atomic_t received_signal = 0;
 132
 133 /* Flag indicating whether the user's terminal is in non-blocking mode. */
 134 static int in_non_blocking_mode = 0;
 135
 136 /* Common data for the client loop code. */
 137 static volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
 138 static int escape_char;         /* Escape character. */
 139 static int escape_pending;      /* Last character was the escape character */
 140 static int last_was_cr;         /* Last character was a newline. */
 141 static int exit_status;         /* Used to store the exit status of the command. */
 142 static int stdin_eof;           /* EOF has been encountered on standard error. */
 143 static Buffer stdin_buffer;     /* Buffer for stdin data. */
 144 static Buffer stdout_buffer;    /* Buffer for stdout data. */
 145 static Buffer stderr_buffer;    /* Buffer for stderr data. */
 146 static u_long stdin_bytes, stdout_bytes, stderr_bytes;
 147 static u_int buffer_high;/* Soft max buffer size. */
 148 static int connection_in;       /* Connection to server (input). */
 149 static int connection_out;      /* Connection to server (output). */
 150 static int need_rekeying;       /* Set to non-zero if rekeying is requested. */
 151 static int session_closed = 0;  /* In SSH2: login session closed. */
 152 static int server_alive_timeouts = 0;
 153
 154 static void client_init_dispatch(void);
 155 int     session_ident = -1;
 156
 157 struct confirm_ctx {
 158         int want_tty;
 159         int want_subsys;
 160         int want_x_fwd;
 161         int want_agent_fwd;
 162         Buffer cmd;
 163         char *term;
 164         struct termios tio;
 165         char **env;
 166 };
 167
 168 /*XXX*/
 169 extern Kex *xxx_kex;
 170
 171 void ssh_process_session2_setup(int, int, int, Buffer *);
 172
 173 /* Restores stdin to blocking mode. */
 174
 175 static void
 176 leave_non_blocking(void)
 177 {
 178         if (in_non_blocking_mode) {
 179                 unset_nonblock(fileno(stdin));
 180                 in_non_blocking_mode = 0;
 181         }
 182 }
 183
 184 /* Puts stdin terminal in non-blocking mode. */
 185
 186 static void
 187 enter_non_blocking(void)
 188 {
 189         in_non_blocking_mode = 1;
 190         set_nonblock(fileno(stdin));
 191 }
 192
 193 /*
 194  * Signal handler for the window change signal (SIGWINCH).  This just sets a
 195  * flag indicating that the window has changed.
 196  */
 197 /*ARGSUSED */
 198 static void
 199 window_change_handler(int sig)
 200 {
 201         received_window_change_signal = 1;
 202         signal(SIGWINCH, window_change_handler);
 203 }
 204
 205 /*
 206  * Signal handler for signals that cause the program to terminate.  These
 207  * signals must be trapped to restore terminal modes.
 208  */
 209 /*ARGSUSED */
 210 static void
 211 signal_handler(int sig)
 212 {
 213         received_signal = sig;
 214         quit_pending = 1;
 215 }
 216
 217 /*
 218  * Returns current time in seconds from Jan 1, 1970 with the maximum
 219  * available resolution.
 220  */
 221
 222 static double
 223 get_current_time(void)
 224 {
 225         struct timeval tv;
 226         gettimeofday(&tv, NULL);
 227         return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
 228 }
 229
 230 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
 231 void
 232 client_x11_get_proto(const char *display, const char *xauth_path,
 233     u_int trusted, char **_proto, char **_data)
 234 {
 235         char cmd[1024];
 236         char line[512];
 237         char xdisplay[512];
 238         static char proto[512], data[512];
 239         FILE *f;
 240         int got_data = 0, generated = 0, do_unlink = 0, i;
 241         char *xauthdir, *xauthfile;
 242         struct stat st;
 243
 244         xauthdir = xauthfile = NULL;
 245         *_proto = proto;
 246         *_data = data;
 247         proto[0] = data[0] = '\0';
 248
 249         if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
 250                 debug("No xauth program.");
 251         } else {
 252                 if (display == NULL) {
 253                         debug("x11_get_proto: DISPLAY not set");
 254                         return;
 255                 }
 256                 /*
 257                  * Handle FamilyLocal case where $DISPLAY does
 258                  * not match an authorization entry.  For this we
 259                  * just try "xauth list unix:displaynum.screennum".
 260                  * XXX: "localhost" match to determine FamilyLocal
 261                  *      is not perfect.
 262                  */
 263                 if (strncmp(display, "localhost:", 10) == 0) {
 264                         snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
 265                             display + 10);
 266                         display = xdisplay;
 267                 }
 268                 if (trusted == 0) {
 269                         xauthdir = xmalloc(MAXPATHLEN);
 270                         xauthfile = xmalloc(MAXPATHLEN);
 271                         strlcpy(xauthdir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
 272                         if (mkdtemp(xauthdir) != NULL) {
 273                                 do_unlink = 1;
 274                                 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
 275                                     xauthdir);
 276                                 snprintf(cmd, sizeof(cmd),
 277                                     "%s -f %s generate %s " SSH_X11_PROTO
 278                                     " untrusted timeout 1200 2>" _PATH_DEVNULL,
 279                                     xauth_path, xauthfile, display);
 280                                 debug2("x11_get_proto: %s", cmd);
 281                                 if (system(cmd) == 0)
 282                                         generated = 1;
 283                         }
 284                 }
 285                 snprintf(cmd, sizeof(cmd),
 286                     "%s %s%s list %s 2>" _PATH_DEVNULL,
 287                     xauth_path,
 288                     generated ? "-f " : "" ,
 289                     generated ? xauthfile : "",
 290                     display);
 291                 debug2("x11_get_proto: %s", cmd);
 292                 f = popen(cmd, "r");
 293                 if (f && fgets(line, sizeof(line), f) &&
 294                     sscanf(line, "%*s %511s %511s", proto, data) == 2)
 295                         got_data = 1;
 296                 if (f)
 297                         pclose(f);
 298         }
 299
 300         if (do_unlink) {
 301                 unlink(xauthfile);
 302                 rmdir(xauthdir);
 303         }
 304         if (xauthdir)
 305                 xfree(xauthdir);
 306         if (xauthfile)
 307                 xfree(xauthfile);
 308
 309         /*
 310          * If we didn't get authentication data, just make up some
 311          * data.  The forwarding code will check the validity of the
 312          * response anyway, and substitute this data.  The X11
 313          * server, however, will ignore this fake data and use
 314          * whatever authentication mechanisms it was using otherwise
 315          * for the local connection.
 316          */
 317         if (!got_data) {
 318                 u_int32_t rnd = 0;
 319
 320                 logit("Warning: No xauth data; "
 321                     "using fake authentication data for X11 forwarding.");
 322                 strlcpy(proto, SSH_X11_PROTO, sizeof proto);
 323                 for (i = 0; i < 16; i++) {
 324                         if (i % 4 == 0)
 325                                 rnd = arc4random();
 326                         snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
 327                             rnd & 0xff);
 328                         rnd >>= 8;
 329                 }
 330         }
 331 }
 332
 333 /*
 334  * This is called when the interactive is entered.  This checks if there is
 335  * an EOF coming on stdin.  We must check this explicitly, as select() does
 336  * not appear to wake up when redirecting from /dev/null.
 337  */
 338
 339 static void
 340 client_check_initial_eof_on_stdin(void)
 341 {
 342         int len;
 343         char buf[1];
 344
 345         /*
 346          * If standard input is to be "redirected from /dev/null", we simply
 347          * mark that we have seen an EOF and send an EOF message to the
 348          * server. Otherwise, we try to read a single character; it appears
 349          * that for some files, such /dev/null, select() never wakes up for
 350          * read for this descriptor, which means that we never get EOF.  This
 351          * way we will get the EOF if stdin comes from /dev/null or similar.
 352          */
 353         if (stdin_null_flag) {
 354                 /* Fake EOF on stdin. */
 355                 debug("Sending eof.");
 356                 stdin_eof = 1;
 357                 packet_start(SSH_CMSG_EOF);
 358                 packet_send();
 359         } else {
 360                 enter_non_blocking();
 361
 362                 /* Check for immediate EOF on stdin. */
 363                 len = read(fileno(stdin), buf, 1);
 364                 if (len == 0) {
 365                         /* EOF.  Record that we have seen it and send EOF to server. */
 366                         debug("Sending eof.");
 367                         stdin_eof = 1;
 368                         packet_start(SSH_CMSG_EOF);
 369                         packet_send();
 370                 } else if (len > 0) {
 371                         /*
 372                          * Got data.  We must store the data in the buffer,
 373                          * and also process it as an escape character if
 374                          * appropriate.
 375                          */
 376                         if ((u_char) buf[0] == escape_char)
 377                                 escape_pending = 1;
 378                         else
 379                                 buffer_append(&stdin_buffer, buf, 1);
 380                 }
 381                 leave_non_blocking();
 382         }
 383 }
 384
 385
 386 /*
 387  * Make packets from buffered stdin data, and buffer them for sending to the
 388  * connection.
 389  */
 390
 391 static void
 392 client_make_packets_from_stdin_data(void)
 393 {
 394         u_int len;
 395
 396         /* Send buffered stdin data to the server. */
 397         while (buffer_len(&stdin_buffer) > 0 &&
 398             packet_not_very_much_data_to_write()) {
 399                 len = buffer_len(&stdin_buffer);
 400                 /* Keep the packets at reasonable size. */
 401                 if (len > packet_get_maxsize())
 402                         len = packet_get_maxsize();
 403                 packet_start(SSH_CMSG_STDIN_DATA);
 404                 packet_put_string(buffer_ptr(&stdin_buffer), len);
 405                 packet_send();
 406                 buffer_consume(&stdin_buffer, len);
 407                 stdin_bytes += len;
 408                 /* If we have a pending EOF, send it now. */
 409                 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
 410                         packet_start(SSH_CMSG_EOF);
 411                         packet_send();
 412                 }
 413         }
 414 }
 415
 416 /*
 417  * Checks if the client window has changed, and sends a packet about it to
 418  * the server if so.  The actual change is detected elsewhere (by a software
 419  * interrupt on Unix); this just checks the flag and sends a message if
 420  * appropriate.
 421  */
 422
 423 static void
 424 client_check_window_change(void)
 425 {
 426         struct winsize ws;
 427
 428         if (! received_window_change_signal)
 429                 return;
 430         /** XXX race */
 431         received_window_change_signal = 0;
 432
 433         debug2("client_check_window_change: changed");
 434
 435         if (compat20) {
 436                 channel_send_window_changes();
 437         } else {
 438                 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
 439                         return;
 440                 packet_start(SSH_CMSG_WINDOW_SIZE);
 441                 packet_put_int((u_int)ws.ws_row);
 442                 packet_put_int((u_int)ws.ws_col);
 443                 packet_put_int((u_int)ws.ws_xpixel);
 444                 packet_put_int((u_int)ws.ws_ypixel);
 445                 packet_send();
 446         }
 447 }
 448
 449 static void
 450 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
 451 {
 452         server_alive_timeouts = 0;
 453         client_global_request_reply_fwd(type, seq, ctxt);
 454 }
 455
 456 static void
 457 server_alive_check(void)
 458 {
 459         if (++server_alive_timeouts > options.server_alive_count_max)
 460                 packet_disconnect("Timeout, server not responding.");
 461         packet_start(SSH2_MSG_GLOBAL_REQUEST);
 462         packet_put_cstring("keepalive@openssh.com");
 463         packet_put_char(1);     /* boolean: want reply */
 464         packet_send();
 465 }
 466
 467 /*
 468  * Waits until the client can do something (some data becomes available on
 469  * one of the file descriptors).
 470  */
 471 static void
 472 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
 473     int *maxfdp, u_int *nallocp, int rekeying)
 474 {
 475         struct timeval tv, *tvp;
 476         int ret;
 477
 478         /* Add any selections by the channel mechanism. */
 479         channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
 480
 481         if (!compat20) {
 482                 /* Read from the connection, unless our buffers are full. */
 483                 if (buffer_len(&stdout_buffer) < buffer_high &&
 484                     buffer_len(&stderr_buffer) < buffer_high &&
 485                     channel_not_very_much_buffered_data())
 486                         FD_SET(connection_in, *readsetp);
 487                 /*
 488                  * Read from stdin, unless we have seen EOF or have very much
 489                  * buffered data to send to the server.
 490                  */
 491                 if (!stdin_eof && packet_not_very_much_data_to_write())
 492                         FD_SET(fileno(stdin), *readsetp);
 493
 494                 /* Select stdout/stderr if have data in buffer. */
 495                 if (buffer_len(&stdout_buffer) > 0)
 496                         FD_SET(fileno(stdout), *writesetp);
 497                 if (buffer_len(&stderr_buffer) > 0)
 498                         FD_SET(fileno(stderr), *writesetp);
 499         } else {
 500                 /* channel_prepare_select could have closed the last channel */
 501                 if (session_closed && !channel_still_open() &&
 502                     !packet_have_data_to_write()) {
 503                         /* clear mask since we did not call select() */
 504                         memset(*readsetp, 0, *nallocp);
 505                         memset(*writesetp, 0, *nallocp);
 506                         return;
 507                 } else {
 508                         FD_SET(connection_in, *readsetp);
 509                 }
 510         }
 511
 512         /* Select server connection if have data to write to the server. */
 513         if (packet_have_data_to_write())
 514                 FD_SET(connection_out, *writesetp);
 515
 516         if (control_fd != -1)
 517                 FD_SET(control_fd, *readsetp);
 518
 519         /*
 520          * Wait for something to happen.  This will suspend the process until
 521          * some selected descriptor can be read, written, or has some other
 522          * event pending.
 523          */
 524
 525         if (options.server_alive_interval == 0 || !compat20)
 526                 tvp = NULL;
 527         else {
 528                 tv.tv_sec = options.server_alive_interval;
 529                 tv.tv_usec = 0;
 530                 tvp = &tv;
 531         }
 532         ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
 533         if (ret < 0) {
 534                 char buf[100];
 535
 536                 /*
 537                  * We have to clear the select masks, because we return.
 538                  * We have to return, because the mainloop checks for the flags
 539                  * set by the signal handlers.
 540                  */
 541                 memset(*readsetp, 0, *nallocp);
 542                 memset(*writesetp, 0, *nallocp);
 543
 544                 if (errno == EINTR)
 545                         return;
 546                 /* Note: we might still have data in the buffers. */
 547                 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
 548                 buffer_append(&stderr_buffer, buf, strlen(buf));
 549                 quit_pending = 1;
 550         } else if (ret == 0)
 551                 server_alive_check();
 552 }
 553
 554 static void
 555 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
 556 {
 557         /* Flush stdout and stderr buffers. */
 558         if (buffer_len(bout) > 0)
 559                 atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
 560         if (buffer_len(berr) > 0)
 561                 atomicio(vwrite, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
 562
 563         leave_raw_mode();
 564
 565         /*
 566          * Free (and clear) the buffer to reduce the amount of data that gets
 567          * written to swap.
 568          */
 569         buffer_free(bin);
 570         buffer_free(bout);
 571         buffer_free(berr);
 572
 573         /* Send the suspend signal to the program itself. */
 574         kill(getpid(), SIGTSTP);
 575
 576         /* Reset window sizes in case they have changed */
 577         received_window_change_signal = 1;
 578
 579         /* OK, we have been continued by the user. Reinitialize buffers. */
 580         buffer_init(bin);
 581         buffer_init(bout);
 582         buffer_init(berr);
 583
 584         enter_raw_mode();
 585 }
 586
 587 static void
 588 client_process_net_input(fd_set *readset)
 589 {
 590         int len;
 591         char buf[8192];
 592
 593         /*
 594          * Read input from the server, and add any such data to the buffer of
 595          * the packet subsystem.
 596          */
 597         if (FD_ISSET(connection_in, readset)) {
 598                 /* Read as much as possible. */
 599                 len = read(connection_in, buf, sizeof(buf));
 600                 if (len == 0) {
 601                         /* Received EOF.  The remote host has closed the connection. */
 602                         snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
 603                                  host);
 604                         buffer_append(&stderr_buffer, buf, strlen(buf));
 605                         quit_pending = 1;
 606                         return;
 607                 }
 608                 /*
 609                  * There is a kernel bug on Solaris that causes select to
 610                  * sometimes wake up even though there is no data available.
 611                  */
 612                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
 613                         len = 0;
 614
 615                 if (len < 0) {
 616                         /* An error has encountered.  Perhaps there is a network problem. */
 617                         snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
 618                                  host, strerror(errno));
 619                         buffer_append(&stderr_buffer, buf, strlen(buf));
 620                         quit_pending = 1;
 621                         return;
 622                 }
 623                 packet_process_incoming(buf, len);
 624         }
 625 }
 626
 627 static void
 628 client_subsystem_reply(int type, u_int32_t seq, void *ctxt)
 629 {
 630         int id;
 631         Channel *c;
 632
 633         id = packet_get_int();
 634         packet_check_eom();
 635
 636         if ((c = channel_lookup(id)) == NULL) {
 637                 error("%s: no channel for id %d", __func__, id);
 638                 return;
 639         }
 640
 641         if (type == SSH2_MSG_CHANNEL_SUCCESS)
 642                 debug2("Request suceeded on channel %d", id);
 643         else if (type == SSH2_MSG_CHANNEL_FAILURE) {
 644                 error("Request failed on channel %d", id);
 645                 channel_free(c);
 646         }
 647 }
 648
 649 static void
 650 client_extra_session2_setup(int id, void *arg)
 651 {
 652         struct confirm_ctx *cctx = arg;
 653         const char *display;
 654         Channel *c;
 655         int i;
 656
 657         if (cctx == NULL)
 658                 fatal("%s: cctx == NULL", __func__);
 659         if ((c = channel_lookup(id)) == NULL)
 660                 fatal("%s: no channel for id %d", __func__, id);
 661
 662         display = getenv("DISPLAY");
 663         if (cctx->want_x_fwd && options.forward_x11 && display != NULL) {
 664                 char *proto, *data;
 665                 /* Get reasonable local authentication information. */
 666                 client_x11_get_proto(display, options.xauth_location,
 667                     options.forward_x11_trusted, &proto, &data);
 668                 /* Request forwarding with authentication spoofing. */
 669                 debug("Requesting X11 forwarding with authentication spoofing.");
 670                 x11_request_forwarding_with_spoofing(id, display, proto, data);
 671                 /* XXX wait for reply */
 672         }
 673
 674         if (cctx->want_agent_fwd && options.forward_agent) {
 675                 debug("Requesting authentication agent forwarding.");
 676                 channel_request_start(id, "auth-agent-req@openssh.com", 0);
 677                 packet_send();
 678         }
 679
 680         client_session2_setup(id, cctx->want_tty, cctx->want_subsys,
 681             cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env,
 682             client_subsystem_reply);
 683
 684         c->confirm_ctx = NULL;
 685         buffer_free(&cctx->cmd);
 686         xfree(cctx->term);
 687         if (cctx->env != NULL) {
 688                 for (i = 0; cctx->env[i] != NULL; i++)
 689                         xfree(cctx->env[i]);
 690                 xfree(cctx->env);
 691         }
 692         xfree(cctx);
 693 }
 694
 695 static void
 696 client_process_control(fd_set *readset)
 697 {
 698         Buffer m;
 699         Channel *c;
 700         int client_fd, new_fd[3], ver, allowed;
 701         socklen_t addrlen;
 702         struct sockaddr_storage addr;
 703         struct confirm_ctx *cctx;
 704         char *cmd;
 705         u_int i, len, env_len, command, flags;
 706         uid_t euid;
 707         gid_t egid;
 708
 709         /*
 710          * Accept connection on control socket
 711          */
 712         if (control_fd == -1 || !FD_ISSET(control_fd, readset))
 713                 return;
 714
 715         memset(&addr, 0, sizeof(addr));
 716         addrlen = sizeof(addr);
 717         if ((client_fd = accept(control_fd,
 718             (struct sockaddr*)&addr, &addrlen)) == -1) {
 719                 error("%s accept: %s", __func__, strerror(errno));
 720                 return;
 721         }
 722
 723         if (getpeereid(client_fd, &euid, &egid) < 0) {
 724                 error("%s getpeereid failed: %s", __func__, strerror(errno));
 725                 close(client_fd);
 726                 return;
 727         }
 728         if ((euid != 0) && (getuid() != euid)) {
 729                 error("control mode uid mismatch: peer euid %u != uid %u",
 730                     (u_int) euid, (u_int) getuid());
 731                 close(client_fd);
 732                 return;
 733         }
 734
 735         unset_nonblock(client_fd);
 736
 737         /* Read command */
 738         buffer_init(&m);
 739         if (ssh_msg_recv(client_fd, &m) == -1) {
 740                 error("%s: client msg_recv failed", __func__);
 741                 close(client_fd);
 742                 buffer_free(&m);
 743                 return;
 744         }
 745         if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
 746                 error("%s: wrong client version %d", __func__, ver);
 747                 buffer_free(&m);
 748                 close(client_fd);
 749                 return;
 750         }
 751
 752         allowed = 1;
 753         command = buffer_get_int(&m);
 754         flags = buffer_get_int(&m);
 755
 756         buffer_clear(&m);
 757
 758         switch (command) {
 759         case SSHMUX_COMMAND_OPEN:
 760                 if (options.control_master == SSHCTL_MASTER_ASK ||
 761                     options.control_master == SSHCTL_MASTER_AUTO_ASK)
 762                         allowed = ask_permission("Allow shared connection "
 763                             "to %s? ", host);
 764                 /* continue below */
 765                 break;
 766         case SSHMUX_COMMAND_TERMINATE:
 767                 if (options.control_master == SSHCTL_MASTER_ASK ||
 768                     options.control_master == SSHCTL_MASTER_AUTO_ASK)
 769                         allowed = ask_permission("Terminate shared connection "
 770                             "to %s? ", host);
 771                 if (allowed)
 772                         quit_pending = 1;
 773                 /* FALLTHROUGH */
 774         case SSHMUX_COMMAND_ALIVE_CHECK:
 775                 /* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */
 776                 buffer_clear(&m);
 777                 buffer_put_int(&m, allowed);
 778                 buffer_put_int(&m, getpid());
 779                 if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 780                         error("%s: client msg_send failed", __func__);
 781                         close(client_fd);
 782                         buffer_free(&m);
 783                         return;
 784                 }
 785                 buffer_free(&m);
 786                 close(client_fd);
 787                 return;
 788         default:
 789                 error("Unsupported command %d", command);
 790                 buffer_free(&m);
 791                 close(client_fd);
 792                 return;
 793         }
 794
 795         /* Reply for SSHMUX_COMMAND_OPEN */
 796         buffer_clear(&m);
 797         buffer_put_int(&m, allowed);
 798         buffer_put_int(&m, getpid());
 799         if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 800                 error("%s: client msg_send failed", __func__);
 801                 close(client_fd);
 802                 buffer_free(&m);
 803                 return;
 804         }
 805
 806         if (!allowed) {
 807                 error("Refused control connection");
 808                 close(client_fd);
 809                 buffer_free(&m);
 810                 return;
 811         }
 812
 813         buffer_clear(&m);
 814         if (ssh_msg_recv(client_fd, &m) == -1) {
 815                 error("%s: client msg_recv failed", __func__);
 816                 close(client_fd);
 817                 buffer_free(&m);
 818                 return;
 819         }
 820         if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
 821                 error("%s: wrong client version %d", __func__, ver);
 822                 buffer_free(&m);
 823                 close(client_fd);
 824                 return;
 825         }
 826
 827         cctx = xcalloc(1, sizeof(*cctx));
 828         cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0;
 829         cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0;
 830         cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0;
 831         cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0;
 832         cctx->term = buffer_get_string(&m, &len);
 833
 834         cmd = buffer_get_string(&m, &len);
 835         buffer_init(&cctx->cmd);
 836         buffer_append(&cctx->cmd, cmd, strlen(cmd));
 837
 838         env_len = buffer_get_int(&m);
 839         env_len = MIN(env_len, 4096);
 840         debug3("%s: receiving %d env vars", __func__, env_len);
 841         if (env_len != 0) {
 842                 cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env));
 843                 for (i = 0; i < env_len; i++)
 844                         cctx->env[i] = buffer_get_string(&m, &len);
 845                 cctx->env[i] = NULL;
 846         }
 847
 848         debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__,
 849             cctx->want_tty, cctx->want_subsys, cmd);
 850         xfree(cmd);
 851
 852         /* Gather fds from client */
 853         new_fd[0] = mm_receive_fd(client_fd);
 854         new_fd[1] = mm_receive_fd(client_fd);
 855         new_fd[2] = mm_receive_fd(client_fd);
 856
 857         debug2("%s: got fds stdin %d, stdout %d, stderr %d", __func__,
 858             new_fd[0], new_fd[1], new_fd[2]);
 859
 860         /* Try to pick up ttymodes from client before it goes raw */
 861         if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1)
 862                 error("%s: tcgetattr: %s", __func__, strerror(errno));
 863
 864         /* This roundtrip is just for synchronisation of ttymodes */
 865         buffer_clear(&m);
 866         if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
 867                 error("%s: client msg_send failed", __func__);
 868                 close(client_fd);
 869                 close(new_fd[0]);
 870                 close(new_fd[1]);
 871                 close(new_fd[2]);
 872                 buffer_free(&m);
 873                 xfree(cctx->term);
 874                 if (env_len != 0) {
 875                         for (i = 0; i < env_len; i++)
 876                                 xfree(cctx->env[i]);
 877                         xfree(cctx->env);
 878                 }
 879                 return;
 880         }
 881         buffer_free(&m);
 882
 883         /* enable nonblocking unless tty */
 884         if (!isatty(new_fd[0]))
 885                 set_nonblock(new_fd[0]);
 886         if (!isatty(new_fd[1]))
 887                 set_nonblock(new_fd[1]);
 888         if (!isatty(new_fd[2]))
 889                 set_nonblock(new_fd[2]);
 890
 891         set_nonblock(client_fd);
 892
 893         c = channel_new("session", SSH_CHANNEL_OPENING,
 894             new_fd[0], new_fd[1], new_fd[2],
 895             CHAN_SES_WINDOW_DEFAULT, CHAN_SES_PACKET_DEFAULT,
 896             CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0);
 897
 898         /* XXX */
 899         c->ctl_fd = client_fd;
 900
 901         debug3("%s: channel_new: %d", __func__, c->self);
 902
 903         channel_send_open(c->self);
 904         channel_register_confirm(c->self, client_extra_session2_setup, cctx);
 905 }
 906
 907 static void
 908 process_cmdline(void)
 909 {
 910         void (*handler)(int);
 911         char *s, *cmd, *cancel_host;
 912         int delete = 0;
 913         int local = 0;
 914         u_short cancel_port;
 915         Forward fwd;
 916
 917         leave_raw_mode();
 918         handler = signal(SIGINT, SIG_IGN);
 919         cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
 920         if (s == NULL)
 921                 goto out;
 922         while (*s && isspace(*s))
 923                 s++;
 924         if (*s == '-')
 925                 s++;    /* Skip cmdline '-', if any */
 926         if (*s == '\0')
 927                 goto out;
 928
 929         if (*s == 'h' || *s == 'H' || *s == '?') {
 930                 logit("Commands:");
 931                 logit("      -L[bind_address:]port:host:hostport    "
 932                     "Request local forward");
 933                 logit("      -R[bind_address:]port:host:hostport    "
 934                     "Request remote forward");
 935                 logit("      -KR[bind_address:]port                 "
 936                     "Cancel remote forward");
 937                 if (!options.permit_local_command)
 938                         goto out;
 939                 logit("      !args                                  "
 940                     "Execute local command");
 941                 goto out;
 942         }
 943
 944         if (*s == '!' && options.permit_local_command) {
 945                 s++;
 946                 ssh_local_cmd(s);
 947                 goto out;
 948         }
 949
 950         if (*s == 'K') {
 951                 delete = 1;
 952                 s++;
 953         }
 954         if (*s != 'L' && *s != 'R') {
 955                 logit("Invalid command.");
 956                 goto out;
 957         }
 958         if (*s == 'L')
 959                 local = 1;
 960         if (local && delete) {
 961                 logit("Not supported.");
 962                 goto out;
 963         }
 964         if ((!local || delete) && !compat20) {
 965                 logit("Not supported for SSH protocol version 1.");
 966                 goto out;
 967         }
 968
 969         s++;
 970         while (*s && isspace(*s))
 971                 s++;
 972
 973         if (delete) {
 974                 cancel_port = 0;
 975                 cancel_host = hpdelim(&s);      /* may be NULL */
 976                 if (s != NULL) {
 977                         cancel_port = a2port(s);
 978                         cancel_host = cleanhostname(cancel_host);
 979                 } else {
 980                         cancel_port = a2port(cancel_host);
 981                         cancel_host = NULL;
 982                 }
 983                 if (cancel_port == 0) {
 984                         logit("Bad forwarding close port");
 985                         goto out;
 986                 }
 987                 channel_request_rforward_cancel(cancel_host, cancel_port);
 988         } else {
 989                 if (!parse_forward(&fwd, s)) {
 990                         logit("Bad forwarding specification.");
 991                         goto out;
 992                 }
 993                 if (local) {
 994                         if (channel_setup_local_fwd_listener(fwd.listen_host,
 995                             fwd.listen_port, fwd.connect_host,
 996                             fwd.connect_port, options.gateway_ports) < 0) {
 997                                 logit("Port forwarding failed.");
 998                                 goto out;
 999                         }
1000                 } else {
1001                         if (channel_request_remote_forwarding(fwd.listen_host,
1002                             fwd.listen_port, fwd.connect_host,
1003                             fwd.connect_port) < 0) {
1004                                 logit("Port forwarding failed.");
1005                                 goto out;
1006                         }
1007                 }
1008
1009                 logit("Forwarding port.");
1010         }
1011
1012 out:
1013         signal(SIGINT, handler);
1014         enter_raw_mode();
1015         if (cmd)
1016                 xfree(cmd);
1017 }
1018
1019 /* process the characters one by one */
1020 static int
1021 process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
1022 {
1023         char string[1024];
1024         pid_t pid;
1025         int bytes = 0;
1026         u_int i;
1027         u_char ch;
1028         char *s;
1029
1030         if (len <= 0)
1031                 return (0);
1032
1033         for (i = 0; i < (u_int)len; i++) {
1034                 /* Get one character at a time. */
1035                 ch = buf[i];
1036
1037                 if (escape_pending) {
1038                         /* We have previously seen an escape character. */
1039                         /* Clear the flag now. */
1040                         escape_pending = 0;
1041
1042                         /* Process the escaped character. */
1043                         switch (ch) {
1044                         case '.':
1045                                 /* Terminate the connection. */
1046                                 snprintf(string, sizeof string, "%c.\r\n", escape_char);
1047                                 buffer_append(berr, string, strlen(string));
1048
1049                                 quit_pending = 1;
1050                                 return -1;
1051
1052                         case 'Z' - 64:
1053                                 /* Suspend the program. */
1054                                 /* Print a message to that effect to the user. */
1055                                 snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
1056                                 buffer_append(berr, string, strlen(string));
1057
1058                                 /* Restore terminal modes and suspend. */
1059                                 client_suspend_self(bin, bout, berr);
1060
1061                                 /* We have been continued. */
1062                                 continue;
1063
1064                         case 'B':
1065                                 if (compat20) {
1066                                         snprintf(string, sizeof string,
1067                                             "%cB\r\n", escape_char);
1068                                         buffer_append(berr, string,
1069                                             strlen(string));
1070                                         channel_request_start(session_ident,
1071                                             "break", 0);
1072                                         packet_put_int(1000);
1073                                         packet_send();
1074                                 }
1075                                 continue;
1076
1077                         case 'R':
1078                                 if (compat20) {
1079                                         if (datafellows & SSH_BUG_NOREKEY)
1080                                                 logit("Server does not support re-keying");
1081                                         else
1082                                                 need_rekeying = 1;
1083                                 }
1084                                 continue;
1085
1086                         case '&':
1087                                 /*
1088                                  * Detach the program (continue to serve connections,
1089                                  * but put in background and no more new connections).
1090                                  */
1091                                 /* Restore tty modes. */
1092                                 leave_raw_mode();
1093
1094                                 /* Stop listening for new connections. */
1095                                 channel_stop_listening();
1096
1097                                 snprintf(string, sizeof string,
1098                                     "%c& [backgrounded]\n", escape_char);
1099                                 buffer_append(berr, string, strlen(string));
1100
1101                                 /* Fork into background. */
1102                                 pid = fork();
1103                                 if (pid < 0) {
1104                                         error("fork: %.100s", strerror(errno));
1105                                         continue;
1106                                 }
1107                                 if (pid != 0) { /* This is the parent. */
1108                                         /* The parent just exits. */
1109                                         exit(0);
1110                                 }
1111                                 /* The child continues serving connections. */
1112                                 if (compat20) {
1113                                         buffer_append(bin, "\004", 1);
1114                                         /* fake EOF on stdin */
1115                                         return -1;
1116                                 } else if (!stdin_eof) {
1117                                         /*
1118                                          * Sending SSH_CMSG_EOF alone does not always appear
1119                                          * to be enough.  So we try to send an EOF character
1120                                          * first.
1121                                          */
1122                                         packet_start(SSH_CMSG_STDIN_DATA);
1123                                         packet_put_string("\004", 1);
1124                                         packet_send();
1125                                         /* Close stdin. */
1126                                         stdin_eof = 1;
1127                                         if (buffer_len(bin) == 0) {
1128                                                 packet_start(SSH_CMSG_EOF);
1129                                                 packet_send();
1130                                         }
1131                                 }
1132                                 continue;
1133
1134                         case '?':
1135                                 snprintf(string, sizeof string,
1136 "%c?\r\n\
1137 Supported escape sequences:\r\n\
1138 %c.  - terminate connection\r\n\
1139 %cB  - send a BREAK to the remote system\r\n\
1140 %cC  - open a command line\r\n\
1141 %cR  - Request rekey (SSH protocol 2 only)\r\n\
1142 %c^Z - suspend ssh\r\n\
1143 %c#  - list forwarded connections\r\n\
1144 %c&  - background ssh (when waiting for connections to terminate)\r\n\
1145 %c?  - this message\r\n\
1146 %c%c  - send the escape character by typing it twice\r\n\
1147 (Note that escapes are only recognized immediately after newline.)\r\n",
1148                                     escape_char, escape_char, escape_char, escape_char,
1149                                     escape_char, escape_char, escape_char, escape_char,
1150                                     escape_char, escape_char, escape_char);
1151                                 buffer_append(berr, string, strlen(string));
1152                                 continue;
1153
1154                         case '#':
1155                                 snprintf(string, sizeof string, "%c#\r\n", escape_char);
1156                                 buffer_append(berr, string, strlen(string));
1157                                 s = channel_open_message();
1158                                 buffer_append(berr, s, strlen(s));
1159                                 xfree(s);
1160                                 continue;
1161
1162                         case 'C':
1163                                 process_cmdline();
1164                                 continue;
1165
1166                         default:
1167                                 if (ch != escape_char) {
1168                                         buffer_put_char(bin, escape_char);
1169                                         bytes++;
1170                                 }
1171                                 /* Escaped characters fall through here */
1172                                 break;
1173                         }
1174                 } else {
1175                         /*
1176                          * The previous character was not an escape char. Check if this
1177                          * is an escape.
1178                          */
1179                         if (last_was_cr && ch == escape_char) {
1180                                 /* It is. Set the flag and continue to next character. */
1181                                 escape_pending = 1;
1182                                 continue;
1183                         }
1184                 }
1185
1186                 /*
1187                  * Normal character.  Record whether it was a newline,
1188                  * and append it to the buffer.
1189                  */
1190                 last_was_cr = (ch == '\r' || ch == '\n');
1191                 buffer_put_char(bin, ch);
1192                 bytes++;
1193         }
1194         return bytes;
1195 }
1196
1197 static void
1198 client_process_input(fd_set *readset)
1199 {
1200         int len;
1201         char buf[8192];
1202
1203         /* Read input from stdin. */
1204         if (FD_ISSET(fileno(stdin), readset)) {
1205                 /* Read as much as possible. */
1206                 len = read(fileno(stdin), buf, sizeof(buf));
1207                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
1208                         return;         /* we'll try again later */
1209                 if (len <= 0) {
1210                         /*
1211                          * Received EOF or error.  They are treated
1212                          * similarly, except that an error message is printed
1213                          * if it was an error condition.
1214                          */
1215                         if (len < 0) {
1216                                 snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
1217                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1218                         }
1219                         /* Mark that we have seen EOF. */
1220                         stdin_eof = 1;
1221                         /*
1222                          * Send an EOF message to the server unless there is
1223                          * data in the buffer.  If there is data in the
1224                          * buffer, no message will be sent now.  Code
1225                          * elsewhere will send the EOF when the buffer
1226                          * becomes empty if stdin_eof is set.
1227                          */
1228                         if (buffer_len(&stdin_buffer) == 0) {
1229                                 packet_start(SSH_CMSG_EOF);
1230                                 packet_send();
1231                         }
1232                 } else if (escape_char == SSH_ESCAPECHAR_NONE) {
1233                         /*
1234                          * Normal successful read, and no escape character.
1235                          * Just append the data to buffer.
1236                          */
1237                         buffer_append(&stdin_buffer, buf, len);
1238                 } else {
1239                         /*
1240                          * Normal, successful read.  But we have an escape character
1241                          * and have to process the characters one by one.
1242                          */
1243                         if (process_escapes(&stdin_buffer, &stdout_buffer,
1244                             &stderr_buffer, buf, len) == -1)
1245                                 return;
1246                 }
1247         }
1248 }
1249
1250 static void
1251 client_process_output(fd_set *writeset)
1252 {
1253         int len;
1254         char buf[100];
1255
1256         /* Write buffered output to stdout. */
1257         if (FD_ISSET(fileno(stdout), writeset)) {
1258                 /* Write as much data as possible. */
1259                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1260                     buffer_len(&stdout_buffer));
1261                 if (len <= 0) {
1262                         if (errno == EINTR || errno == EAGAIN)
1263                                 len = 0;
1264                         else {
1265                                 /*
1266                                  * An error or EOF was encountered.  Put an
1267                                  * error message to stderr buffer.
1268                                  */
1269                                 snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
1270                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1271                                 quit_pending = 1;
1272                                 return;
1273                         }
1274                 }
1275                 /* Consume printed data from the buffer. */
1276                 buffer_consume(&stdout_buffer, len);
1277                 stdout_bytes += len;
1278         }
1279         /* Write buffered output to stderr. */
1280         if (FD_ISSET(fileno(stderr), writeset)) {
1281                 /* Write as much data as possible. */
1282                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1283                     buffer_len(&stderr_buffer));
1284                 if (len <= 0) {
1285                         if (errno == EINTR || errno == EAGAIN)
1286                                 len = 0;
1287                         else {
1288                                 /* EOF or error, but can't even print error message. */
1289                                 quit_pending = 1;
1290                                 return;
1291                         }
1292                 }
1293                 /* Consume printed characters from the buffer. */
1294                 buffer_consume(&stderr_buffer, len);
1295                 stderr_bytes += len;
1296         }
1297 }
1298
1299 /*
1300  * Get packets from the connection input buffer, and process them as long as
1301  * there are packets available.
1302  *
1303  * Any unknown packets received during the actual
1304  * session cause the session to terminate.  This is
1305  * intended to make debugging easier since no
1306  * confirmations are sent.  Any compatible protocol
1307  * extensions must be negotiated during the
1308  * preparatory phase.
1309  */
1310
1311 static void
1312 client_process_buffered_input_packets(void)
1313 {
1314         dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL);
1315 }
1316
1317 /* scan buf[] for '~' before sending data to the peer */
1318
1319 static int
1320 simple_escape_filter(Channel *c, char *buf, int len)
1321 {
1322         /* XXX we assume c->extended is writeable */
1323         return process_escapes(&c->input, &c->output, &c->extended, buf, len);
1324 }
1325
1326 static void
1327 client_channel_closed(int id, void *arg)
1328 {
1329         channel_cancel_cleanup(id);
1330         session_closed = 1;
1331         leave_raw_mode();
1332 }
1333
1334 /*
1335  * Implements the interactive session with the server.  This is called after
1336  * the user has been authenticated, and a command has been started on the
1337  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1338  * used as an escape character for terminating or suspending the session.
1339  */
1340
1341 int
1342 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1343 {
1344         fd_set *readset = NULL, *writeset = NULL;
1345         double start_time, total_time;
1346         int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1347         u_int nalloc = 0;
1348         char buf[100];
1349
1350         debug("Entering interactive session.");
1351
1352         start_time = get_current_time();
1353
1354         /* Initialize variables. */
1355         escape_pending = 0;
1356         last_was_cr = 1;
1357         exit_status = -1;
1358         stdin_eof = 0;
1359         buffer_high = 64 * 1024;
1360         connection_in = packet_get_connection_in();
1361         connection_out = packet_get_connection_out();
1362         max_fd = MAX(connection_in, connection_out);
1363         if (control_fd != -1)
1364                 max_fd = MAX(max_fd, control_fd);
1365
1366         if (!compat20) {
1367                 /* enable nonblocking unless tty */
1368                 if (!isatty(fileno(stdin)))
1369                         set_nonblock(fileno(stdin));
1370                 if (!isatty(fileno(stdout)))
1371                         set_nonblock(fileno(stdout));
1372                 if (!isatty(fileno(stderr)))
1373                         set_nonblock(fileno(stderr));
1374                 max_fd = MAX(max_fd, fileno(stdin));
1375                 max_fd = MAX(max_fd, fileno(stdout));
1376                 max_fd = MAX(max_fd, fileno(stderr));
1377         }
1378         stdin_bytes = 0;
1379         stdout_bytes = 0;
1380         stderr_bytes = 0;
1381         quit_pending = 0;
1382         escape_char = escape_char_arg;
1383
1384         /* Initialize buffers. */
1385         buffer_init(&stdin_buffer);
1386         buffer_init(&stdout_buffer);
1387         buffer_init(&stderr_buffer);
1388
1389         client_init_dispatch();
1390
1391         /*
1392          * Set signal handlers, (e.g. to restore non-blocking mode)
1393          * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1394          */
1395         if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1396                 signal(SIGHUP, signal_handler);
1397         if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1398                 signal(SIGINT, signal_handler);
1399         if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1400                 signal(SIGQUIT, signal_handler);
1401         if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1402                 signal(SIGTERM, signal_handler);
1403         signal(SIGWINCH, window_change_handler);
1404
1405         if (have_pty)
1406                 enter_raw_mode();
1407
1408         if (compat20) {
1409                 session_ident = ssh2_chan_id;
1410                 if (escape_char != SSH_ESCAPECHAR_NONE)
1411                         channel_register_filter(session_ident,
1412                             simple_escape_filter, NULL);
1413                 if (session_ident != -1)
1414                         channel_register_cleanup(session_ident,
1415                             client_channel_closed, 0);
1416         } else {
1417                 /* Check if we should immediately send eof on stdin. */
1418                 client_check_initial_eof_on_stdin();
1419         }
1420
1421         /* Main loop of the client for the interactive session mode. */
1422         while (!quit_pending) {
1423
1424                 /* Process buffered packets sent by the server. */
1425                 client_process_buffered_input_packets();
1426
1427                 if (compat20 && session_closed && !channel_still_open())
1428                         break;
1429
1430                 rekeying = (xxx_kex != NULL && !xxx_kex->done);
1431
1432                 if (rekeying) {
1433                         debug("rekeying in progress");
1434                 } else {
1435                         /*
1436                          * Make packets of buffered stdin data, and buffer
1437                          * them for sending to the server.
1438                          */
1439                         if (!compat20)
1440                                 client_make_packets_from_stdin_data();
1441
1442                         /*
1443                          * Make packets from buffered channel data, and
1444                          * enqueue them for sending to the server.
1445                          */
1446                         if (packet_not_very_much_data_to_write())
1447                                 channel_output_poll();
1448
1449                         /*
1450                          * Check if the window size has changed, and buffer a
1451                          * message about it to the server if so.
1452                          */
1453                         client_check_window_change();
1454
1455                         if (quit_pending)
1456                                 break;
1457                 }
1458                 /*
1459                  * Wait until we have something to do (something becomes
1460                  * available on one of the descriptors).
1461                  */
1462                 max_fd2 = max_fd;
1463                 client_wait_until_can_do_something(&readset, &writeset,
1464                     &max_fd2, &nalloc, rekeying);
1465
1466                 if (quit_pending)
1467                         break;
1468
1469                 /* Do channel operations unless rekeying in progress. */
1470                 if (!rekeying) {
1471                         channel_after_select(readset, writeset);
1472                         if (need_rekeying || packet_need_rekeying()) {
1473                                 debug("need rekeying");
1474                                 xxx_kex->done = 0;
1475                                 kex_send_kexinit(xxx_kex);
1476                                 need_rekeying = 0;
1477                         }
1478                 }
1479
1480                 /* Buffer input from the connection.  */
1481                 client_process_net_input(readset);
1482
1483                 /* Accept control connections.  */
1484                 client_process_control(readset);
1485
1486                 if (quit_pending)
1487                         break;
1488
1489                 if (!compat20) {
1490                         /* Buffer data from stdin */
1491                         client_process_input(readset);
1492                         /*
1493                          * Process output to stdout and stderr.  Output to
1494                          * the connection is processed elsewhere (above).
1495                          */
1496                         client_process_output(writeset);
1497                 }
1498
1499                 /* Send as much buffered packet data as possible to the sender. */
1500                 if (FD_ISSET(connection_out, writeset))
1501                         packet_write_poll();
1502         }
1503         if (readset)
1504                 xfree(readset);
1505         if (writeset)
1506                 xfree(writeset);
1507
1508         /* Terminate the session. */
1509
1510         /* Stop watching for window change. */
1511         signal(SIGWINCH, SIG_DFL);
1512
1513         channel_free_all();
1514
1515         if (have_pty)
1516                 leave_raw_mode();
1517
1518         /* restore blocking io */
1519         if (!isatty(fileno(stdin)))
1520                 unset_nonblock(fileno(stdin));
1521         if (!isatty(fileno(stdout)))
1522                 unset_nonblock(fileno(stdout));
1523         if (!isatty(fileno(stderr)))
1524                 unset_nonblock(fileno(stderr));
1525
1526         /*
1527          * If there was no shell or command requested, there will be no remote
1528          * exit status to be returned.  In that case, clear error code if the
1529          * connection was deliberately terminated at this end.
1530          */
1531         if (no_shell_flag && received_signal == SIGTERM) {
1532                 received_signal = 0;
1533                 exit_status = 0;
1534         }
1535
1536         if (received_signal)
1537                 fatal("Killed by signal %d.", (int) received_signal);
1538
1539         /*
1540          * In interactive mode (with pseudo tty) display a message indicating
1541          * that the connection has been closed.
1542          */
1543         if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1544                 snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
1545                 buffer_append(&stderr_buffer, buf, strlen(buf));
1546         }
1547
1548         /* Output any buffered data for stdout. */
1549         while (buffer_len(&stdout_buffer) > 0) {
1550                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1551                     buffer_len(&stdout_buffer));
1552                 if (len <= 0) {
1553                         error("Write failed flushing stdout buffer.");
1554                         break;
1555                 }
1556                 buffer_consume(&stdout_buffer, len);
1557                 stdout_bytes += len;
1558         }
1559
1560         /* Output any buffered data for stderr. */
1561         while (buffer_len(&stderr_buffer) > 0) {
1562                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1563                     buffer_len(&stderr_buffer));
1564                 if (len <= 0) {
1565                         error("Write failed flushing stderr buffer.");
1566                         break;
1567                 }
1568                 buffer_consume(&stderr_buffer, len);
1569                 stderr_bytes += len;
1570         }
1571
1572         /* Clear and free any buffers. */
1573         memset(buf, 0, sizeof(buf));
1574         buffer_free(&stdin_buffer);
1575         buffer_free(&stdout_buffer);
1576         buffer_free(&stderr_buffer);
1577
1578         /* Report bytes transferred, and transfer rates. */
1579         total_time = get_current_time() - start_time;
1580         debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
1581             stdin_bytes, stdout_bytes, stderr_bytes, total_time);
1582         if (total_time > 0)
1583                 debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
1584                     stdin_bytes / total_time, stdout_bytes / total_time,
1585                     stderr_bytes / total_time);
1586
1587         /* Return the exit status of the program. */
1588         debug("Exit status %d", exit_status);
1589         return exit_status;
1590 }
1591
1592 /*********/
1593
1594 static void
1595 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1596 {
1597         u_int data_len;
1598         char *data = packet_get_string(&data_len);
1599         packet_check_eom();
1600         buffer_append(&stdout_buffer, data, data_len);
1601         memset(data, 0, data_len);
1602         xfree(data);
1603 }
1604 static void
1605 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1606 {
1607         u_int data_len;
1608         char *data = packet_get_string(&data_len);
1609         packet_check_eom();
1610         buffer_append(&stderr_buffer, data, data_len);
1611         memset(data, 0, data_len);
1612         xfree(data);
1613 }
1614 static void
1615 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1616 {
1617         exit_status = packet_get_int();
1618         packet_check_eom();
1619         /* Acknowledge the exit. */
1620         packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1621         packet_send();
1622         /*
1623          * Must wait for packet to be sent since we are
1624          * exiting the loop.
1625          */
1626         packet_write_wait();
1627         /* Flag that we want to exit. */
1628         quit_pending = 1;
1629 }
1630 static void
1631 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1632 {
1633         Channel *c = NULL;
1634         int remote_id, sock;
1635
1636         /* Read the remote channel number from the message. */
1637         remote_id = packet_get_int();
1638         packet_check_eom();
1639
1640         /*
1641          * Get a connection to the local authentication agent (this may again
1642          * get forwarded).
1643          */
1644         sock = ssh_get_authentication_socket();
1645
1646         /*
1647          * If we could not connect the agent, send an error message back to
1648          * the server. This should never happen unless the agent dies,
1649          * because authentication forwarding is only enabled if we have an
1650          * agent.
1651          */
1652         if (sock >= 0) {
1653                 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1654                     -1, 0, 0, 0, "authentication agent connection", 1);
1655                 c->remote_id = remote_id;
1656                 c->force_drain = 1;
1657         }
1658         if (c == NULL) {
1659                 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1660                 packet_put_int(remote_id);
1661         } else {
1662                 /* Send a confirmation to the remote host. */
1663                 debug("Forwarding authentication connection.");
1664                 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1665                 packet_put_int(remote_id);
1666                 packet_put_int(c->self);
1667         }
1668         packet_send();
1669 }
1670
1671 static Channel *
1672 client_request_forwarded_tcpip(const char *request_type, int rchan)
1673 {
1674         Channel *c = NULL;
1675         char *listen_address, *originator_address;
1676         int listen_port, originator_port;
1677         int sock;
1678
1679         /* Get rest of the packet */
1680         listen_address = packet_get_string(NULL);
1681         listen_port = packet_get_int();
1682         originator_address = packet_get_string(NULL);
1683         originator_port = packet_get_int();
1684         packet_check_eom();
1685
1686         debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1687             listen_address, listen_port, originator_address, originator_port);
1688
1689         sock = channel_connect_by_listen_address(listen_port);
1690         if (sock < 0) {
1691                 xfree(originator_address);
1692                 xfree(listen_address);
1693                 return NULL;
1694         }
1695         c = channel_new("forwarded-tcpip",
1696             SSH_CHANNEL_CONNECTING, sock, sock, -1,
1697             CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1698             originator_address, 1);
1699         xfree(originator_address);
1700         xfree(listen_address);
1701         return c;
1702 }
1703
1704 static Channel *
1705 client_request_x11(const char *request_type, int rchan)
1706 {
1707         Channel *c = NULL;
1708         char *originator;
1709         int originator_port;
1710         int sock;
1711
1712         if (!options.forward_x11) {
1713                 error("Warning: ssh server tried X11 forwarding.");
1714                 error("Warning: this is probably a break-in attempt by a malicious server.");
1715                 return NULL;
1716         }
1717         originator = packet_get_string(NULL);
1718         if (datafellows & SSH_BUG_X11FWD) {
1719                 debug2("buggy server: x11 request w/o originator_port");
1720                 originator_port = 0;
1721         } else {
1722                 originator_port = packet_get_int();
1723         }
1724         packet_check_eom();
1725         /* XXX check permission */
1726         debug("client_request_x11: request from %s %d", originator,
1727             originator_port);
1728         xfree(originator);
1729         sock = x11_connect_display();
1730         if (sock < 0)
1731                 return NULL;
1732         c = channel_new("x11",
1733             SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1734             CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1735         c->force_drain = 1;
1736         return c;
1737 }
1738
1739 static Channel *
1740 client_request_agent(const char *request_type, int rchan)
1741 {
1742         Channel *c = NULL;
1743         int sock;
1744
1745         if (!options.forward_agent) {
1746                 error("Warning: ssh server tried agent forwarding.");
1747                 error("Warning: this is probably a break-in attempt by a malicious server.");
1748                 return NULL;
1749         }
1750         sock =  ssh_get_authentication_socket();
1751         if (sock < 0)
1752                 return NULL;
1753         c = channel_new("authentication agent connection",
1754             SSH_CHANNEL_OPEN, sock, sock, -1,
1755             CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1756             "authentication agent connection", 1);
1757         c->force_drain = 1;
1758         return c;
1759 }
1760
1761 /* XXXX move to generic input handler */
1762 static void
1763 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1764 {
1765         Channel *c = NULL;
1766         char *ctype;
1767         int rchan;
1768         u_int rmaxpack, rwindow, len;
1769
1770         ctype = packet_get_string(&len);
1771         rchan = packet_get_int();
1772         rwindow = packet_get_int();
1773         rmaxpack = packet_get_int();
1774
1775         debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1776             ctype, rchan, rwindow, rmaxpack);
1777
1778         if (strcmp(ctype, "forwarded-tcpip") == 0) {
1779                 c = client_request_forwarded_tcpip(ctype, rchan);
1780         } else if (strcmp(ctype, "x11") == 0) {
1781                 c = client_request_x11(ctype, rchan);
1782         } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1783                 c = client_request_agent(ctype, rchan);
1784         }
1785 /* XXX duplicate : */
1786         if (c != NULL) {
1787                 debug("confirm %s", ctype);
1788                 c->remote_id = rchan;
1789                 c->remote_window = rwindow;
1790                 c->remote_maxpacket = rmaxpack;
1791                 if (c->type != SSH_CHANNEL_CONNECTING) {
1792                         packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1793                         packet_put_int(c->remote_id);
1794                         packet_put_int(c->self);
1795                         packet_put_int(c->local_window);
1796                         packet_put_int(c->local_maxpacket);
1797                         packet_send();
1798                 }
1799         } else {
1800                 debug("failure %s", ctype);
1801                 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1802                 packet_put_int(rchan);
1803                 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1804                 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1805                         packet_put_cstring("open failed");
1806                         packet_put_cstring("");
1807                 }
1808                 packet_send();
1809         }
1810         xfree(ctype);
1811 }
1812 static void
1813 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1814 {
1815         Channel *c = NULL;
1816         int exitval, id, reply, success = 0;
1817         char *rtype;
1818
1819         id = packet_get_int();
1820         rtype = packet_get_string(NULL);
1821         reply = packet_get_char();
1822
1823         debug("client_input_channel_req: channel %d rtype %s reply %d",
1824             id, rtype, reply);
1825
1826         if (id == -1) {
1827                 error("client_input_channel_req: request for channel -1");
1828         } else if ((c = channel_lookup(id)) == NULL) {
1829                 error("client_input_channel_req: channel %d: unknown channel", id);
1830         } else if (strcmp(rtype, "exit-status") == 0) {
1831                 exitval = packet_get_int();
1832                 if (id == session_ident) {
1833                         success = 1;
1834                         exit_status = exitval;
1835                 } else if (c->ctl_fd == -1) {
1836                         error("client_input_channel_req: unexpected channel %d",
1837                             session_ident);
1838                 } else {
1839                         atomicio(vwrite, c->ctl_fd, &exitval, sizeof(exitval));
1840                         success = 1;
1841                 }
1842                 packet_check_eom();
1843         }
1844         if (reply) {
1845                 packet_start(success ?
1846                     SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1847                 packet_put_int(id);
1848                 packet_send();
1849         }
1850         xfree(rtype);
1851 }
1852 static void
1853 client_input_global_request(int type, u_int32_t seq, void *ctxt)
1854 {
1855         char *rtype;
1856         int want_reply;
1857         int success = 0;
1858
1859         rtype = packet_get_string(NULL);
1860         want_reply = packet_get_char();
1861         debug("client_input_global_request: rtype %s want_reply %d",
1862             rtype, want_reply);
1863         if (want_reply) {
1864                 packet_start(success ?
1865                     SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1866                 packet_send();
1867                 packet_write_wait();
1868         }
1869         xfree(rtype);
1870 }
1871
1872 void
1873 client_session2_setup(int id, int want_tty, int want_subsystem,
1874     const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env,
1875     dispatch_fn *subsys_repl)
1876 {
1877         int len;
1878         Channel *c = NULL;
1879
1880         debug2("%s: id %d", __func__, id);
1881
1882         if ((c = channel_lookup(id)) == NULL)
1883                 fatal("client_session2_setup: channel %d: unknown channel", id);
1884
1885         if (want_tty) {
1886                 struct winsize ws;
1887                 struct termios tio;
1888
1889                 /* Store window size in the packet. */
1890                 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
1891                         memset(&ws, 0, sizeof(ws));
1892
1893                 channel_request_start(id, "pty-req", 0);
1894                 packet_put_cstring(term != NULL ? term : "");
1895                 packet_put_int((u_int)ws.ws_col);
1896                 packet_put_int((u_int)ws.ws_row);
1897                 packet_put_int((u_int)ws.ws_xpixel);
1898                 packet_put_int((u_int)ws.ws_ypixel);
1899                 tio = get_saved_tio();
1900                 tty_make_modes(-1, tiop != NULL ? tiop : &tio);
1901                 packet_send();
1902                 /* XXX wait for reply */
1903                 c->client_tty = 1;
1904         }
1905
1906         /* Transfer any environment variables from client to server */
1907         if (options.num_send_env != 0 && env != NULL) {
1908                 int i, j, matched;
1909                 char *name, *val;
1910
1911                 debug("Sending environment.");
1912                 for (i = 0; env[i] != NULL; i++) {
1913                         /* Split */
1914                         name = xstrdup(env[i]);
1915                         if ((val = strchr(name, '=')) == NULL) {
1916                                 xfree(name);
1917                                 continue;
1918                         }
1919                         *val++ = '\0';
1920
1921                         matched = 0;
1922                         for (j = 0; j < options.num_send_env; j++) {
1923                                 if (match_pattern(name, options.send_env[j])) {
1924                                         matched = 1;
1925                                         break;
1926                                 }
1927                         }
1928                         if (!matched) {
1929                                 debug3("Ignored env %s", name);
1930                                 xfree(name);
1931                                 continue;
1932                         }
1933
1934                         debug("Sending env %s = %s", name, val);
1935                         channel_request_start(id, "env", 0);
1936                         packet_put_cstring(name);
1937                         packet_put_cstring(val);
1938                         packet_send();
1939                         xfree(name);
1940                 }
1941         }
1942
1943         len = buffer_len(cmd);
1944         if (len > 0) {
1945                 if (len > 900)
1946                         len = 900;
1947                 if (want_subsystem) {
1948                         debug("Sending subsystem: %.*s", len, (u_char*)buffer_ptr(cmd));
1949                         channel_request_start(id, "subsystem", subsys_repl != NULL);
1950                         if (subsys_repl != NULL) {
1951                                 /* register callback for reply */
1952                                 /* XXX we assume that client_loop has already been called */
1953                                 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, subsys_repl);
1954                                 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, subsys_repl);
1955                         }
1956                 } else {
1957                         debug("Sending command: %.*s", len, (u_char*)buffer_ptr(cmd));
1958                         channel_request_start(id, "exec", 0);
1959                 }
1960                 packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
1961                 packet_send();
1962         } else {
1963                 channel_request_start(id, "shell", 0);
1964                 packet_send();
1965         }
1966 }
1967
1968 static void
1969 client_init_dispatch_20(void)
1970 {
1971         dispatch_init(&dispatch_protocol_error);
1972
1973         dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1974         dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1975         dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1976         dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1977         dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1978         dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1979         dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1980         dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1981         dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1982         dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1983
1984         /* rekeying */
1985         dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1986
1987         /* global request reply messages */
1988         dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
1989         dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
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 static void
2011 client_init_dispatch_15(void)
2012 {
2013         client_init_dispatch_13();
2014         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2015         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2016 }
2017 static void
2018 client_init_dispatch(void)
2019 {
2020         if (compat20)
2021                 client_init_dispatch_20();
2022         else if (compat13)
2023                 client_init_dispatch_13();
2024         else
2025                 client_init_dispatch_15();
2026 }
2027
2028 /* client specific fatal cleanup */
2029 void
2030 cleanup_exit(int i)
2031 {
2032         leave_raw_mode();
2033         leave_non_blocking();
2034         if (options.control_path != NULL && control_fd != -1)
2035                 unlink(options.control_path);
2036         _exit(i);
2037 }