crypto/openssh/clientloop.c

   1 /* $OpenBSD: clientloop.c,v 1.231 2011/01/16 12:05:59 djm Exp $ */
   2 /* $FreeBSD$ */
   3 /*
   4  * Author: Tatu Ylonen <ylo@cs.hut.fi>
   5  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
   6  *                    All rights reserved
   7  * The main loop for the interactive session (client side).
   8  *
   9  * As far as I am concerned, the code I have written for this software
  10  * can be used freely for any purpose.  Any derived versions of this
  11  * software must be clearly marked as such, and if the derived work is
  12  * incompatible with the protocol description in the RFC file, it must be
  13  * called by a name other than "ssh" or "Secure Shell".
  14  *
  15  *
  16  * Copyright (c) 1999 Theo de Raadt.  All rights reserved.
  17  *
  18  * Redistribution and use in source and binary forms, with or without
  19  * modification, are permitted provided that the following conditions
  20  * are met:
  21  * 1. Redistributions of source code must retain the above copyright
  22  *    notice, this list of conditions and the following disclaimer.
  23  * 2. Redistributions in binary form must reproduce the above copyright
  24  *    notice, this list of conditions and the following disclaimer in the
  25  *    documentation and/or other materials provided with the distribution.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  28  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  29  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  30  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  31  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  32  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  33  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  34  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  35  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  36  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  37  *
  38  *
  39  * SSH2 support added by Markus Friedl.
  40  * Copyright (c) 1999, 2000, 2001 Markus Friedl.  All rights reserved.
  41  *
  42  * Redistribution and use in source and binary forms, with or without
  43  * modification, are permitted provided that the following conditions
  44  * are met:
  45  * 1. Redistributions of source code must retain the above copyright
  46  *    notice, this list of conditions and the following disclaimer.
  47  * 2. Redistributions in binary form must reproduce the above copyright
  48  *    notice, this list of conditions and the following disclaimer in the
  49  *    documentation and/or other materials provided with the distribution.
  50  *
  51  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  52  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  53  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  54  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  55  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  56  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  57  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  58  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  59  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  60  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  61  */
  62
  63 #include "includes.h"
  64
  65 #include <sys/types.h>
  66 #include <sys/ioctl.h>
  67 #include <sys/param.h>
  68 #ifdef HAVE_SYS_STAT_H
  69 # include <sys/stat.h>
  70 #endif
  71 #ifdef HAVE_SYS_TIME_H
  72 # include <sys/time.h>
  73 #endif
  74 #include <sys/socket.h>
  75
  76 #include <ctype.h>
  77 #include <errno.h>
  78 #ifdef HAVE_PATHS_H
  79 #include <paths.h>
  80 #endif
  81 #include <signal.h>
  82 #include <stdarg.h>
  83 #include <stdio.h>
  84 #include <stdlib.h>
  85 #include <string.h>
  86 #include <termios.h>
  87 #include <pwd.h>
  88 #include <unistd.h>
  89
  90 #include "openbsd-compat/sys-queue.h"
  91 #include "xmalloc.h"
  92 #include "ssh.h"
  93 #include "ssh1.h"
  94 #include "ssh2.h"
  95 #include "packet.h"
  96 #include "buffer.h"
  97 #include "compat.h"
  98 #include "channels.h"
  99 #include "dispatch.h"
 100 #include "key.h"
 101 #include "cipher.h"
 102 #include "kex.h"
 103 #include "log.h"
 104 #include "readconf.h"
 105 #include "clientloop.h"
 106 #include "sshconnect.h"
 107 #include "authfd.h"
 108 #include "atomicio.h"
 109 #include "sshpty.h"
 110 #include "misc.h"
 111 #include "match.h"
 112 #include "msg.h"
 113 #include "roaming.h"
 114
 115 /* import options */
 116 extern Options options;
 117
 118 /* Flag indicating that stdin should be redirected from /dev/null. */
 119 extern int stdin_null_flag;
 120
 121 /* Flag indicating that no shell has been requested */
 122 extern int no_shell_flag;
 123
 124 /* Control socket */
 125 extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */
 126
 127 /*
 128  * Name of the host we are connecting to.  This is the name given on the
 129  * command line, or the HostName specified for the user-supplied name in a
 130  * configuration file.
 131  */
 132 extern char *host;
 133
 134 /* Force TTY allocation */
 135 extern int force_tty_flag;
 136
 137 /*
 138  * Flag to indicate that we have received a window change signal which has
 139  * not yet been processed.  This will cause a message indicating the new
 140  * window size to be sent to the server a little later.  This is volatile
 141  * because this is updated in a signal handler.
 142  */
 143 static volatile sig_atomic_t received_window_change_signal = 0;
 144 static volatile sig_atomic_t received_signal = 0;
 145
 146 /* Flag indicating whether the user's terminal is in non-blocking mode. */
 147 static int in_non_blocking_mode = 0;
 148
 149 /* Time when backgrounded control master using ControlPersist should exit */
 150 static time_t control_persist_exit_time = 0;
 151
 152 /* Common data for the client loop code. */
 153 volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
 154 static int escape_char1;        /* Escape character. (proto1 only) */
 155 static int escape_pending1;     /* Last character was an escape (proto1 only) */
 156 static int last_was_cr;         /* Last character was a newline. */
 157 static int exit_status;         /* Used to store the command exit status. */
 158 static int stdin_eof;           /* EOF has been encountered on stderr. */
 159 static Buffer stdin_buffer;     /* Buffer for stdin data. */
 160 static Buffer stdout_buffer;    /* Buffer for stdout data. */
 161 static Buffer stderr_buffer;    /* Buffer for stderr data. */
 162 static u_int buffer_high;       /* Soft max buffer size. */
 163 static int connection_in;       /* Connection to server (input). */
 164 static int connection_out;      /* Connection to server (output). */
 165 static int need_rekeying;       /* Set to non-zero if rekeying is requested. */
 166 static int session_closed;      /* In SSH2: login session closed. */
 167 static int x11_refuse_time;     /* If >0, refuse x11 opens after this time. */
 168
 169 static void client_init_dispatch(void);
 170 int     session_ident = -1;
 171
 172 int     session_resumed = 0;
 173
 174 /* Track escape per proto2 channel */
 175 struct escape_filter_ctx {
 176         int escape_pending;
 177         int escape_char;
 178 };
 179
 180 /* Context for channel confirmation replies */
 181 struct channel_reply_ctx {
 182         const char *request_type;
 183         int id, do_close;
 184 };
 185
 186 /* Global request success/failure callbacks */
 187 struct global_confirm {
 188         TAILQ_ENTRY(global_confirm) entry;
 189         global_confirm_cb *cb;
 190         void *ctx;
 191         int ref_count;
 192 };
 193 TAILQ_HEAD(global_confirms, global_confirm);
 194 static struct global_confirms global_confirms =
 195     TAILQ_HEAD_INITIALIZER(global_confirms);
 196
 197 /*XXX*/
 198 extern Kex *xxx_kex;
 199
 200 void ssh_process_session2_setup(int, int, int, Buffer *);
 201
 202 /* Restores stdin to blocking mode. */
 203
 204 static void
 205 leave_non_blocking(void)
 206 {
 207         if (in_non_blocking_mode) {
 208                 unset_nonblock(fileno(stdin));
 209                 in_non_blocking_mode = 0;
 210         }
 211 }
 212
 213 /* Puts stdin terminal in non-blocking mode. */
 214
 215 static void
 216 enter_non_blocking(void)
 217 {
 218         in_non_blocking_mode = 1;
 219         set_nonblock(fileno(stdin));
 220 }
 221
 222 /*
 223  * Signal handler for the window change signal (SIGWINCH).  This just sets a
 224  * flag indicating that the window has changed.
 225  */
 226 /*ARGSUSED */
 227 static void
 228 window_change_handler(int sig)
 229 {
 230         received_window_change_signal = 1;
 231         signal(SIGWINCH, window_change_handler);
 232 }
 233
 234 /*
 235  * Signal handler for signals that cause the program to terminate.  These
 236  * signals must be trapped to restore terminal modes.
 237  */
 238 /*ARGSUSED */
 239 static void
 240 signal_handler(int sig)
 241 {
 242         received_signal = sig;
 243         quit_pending = 1;
 244 }
 245
 246 /*
 247  * Returns current time in seconds from Jan 1, 1970 with the maximum
 248  * available resolution.
 249  */
 250
 251 static double
 252 get_current_time(void)
 253 {
 254         struct timeval tv;
 255         gettimeofday(&tv, NULL);
 256         return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
 257 }
 258
 259 /*
 260  * Sets control_persist_exit_time to the absolute time when the
 261  * backgrounded control master should exit due to expiry of the
 262  * ControlPersist timeout.  Sets it to 0 if we are not a backgrounded
 263  * control master process, or if there is no ControlPersist timeout.
 264  */
 265 static void
 266 set_control_persist_exit_time(void)
 267 {
 268         if (muxserver_sock == -1 || !options.control_persist
 269             || options.control_persist_timeout == 0)
 270                 /* not using a ControlPersist timeout */
 271                 control_persist_exit_time = 0;
 272         else if (channel_still_open()) {
 273                 /* some client connections are still open */
 274                 if (control_persist_exit_time > 0)
 275                         debug2("%s: cancel scheduled exit", __func__);
 276                 control_persist_exit_time = 0;
 277         } else if (control_persist_exit_time <= 0) {
 278                 /* a client connection has recently closed */
 279                 control_persist_exit_time = time(NULL) +
 280                         (time_t)options.control_persist_timeout;
 281                 debug2("%s: schedule exit in %d seconds", __func__,
 282                     options.control_persist_timeout);
 283         }
 284         /* else we are already counting down to the timeout */
 285 }
 286
 287 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
 288 void
 289 client_x11_get_proto(const char *display, const char *xauth_path,
 290     u_int trusted, u_int timeout, char **_proto, char **_data)
 291 {
 292         char cmd[1024];
 293         char line[512];
 294         char xdisplay[512];
 295         static char proto[512], data[512];
 296         FILE *f;
 297         int got_data = 0, generated = 0, do_unlink = 0, i;
 298         char *xauthdir, *xauthfile;
 299         struct stat st;
 300         u_int now;
 301
 302         xauthdir = xauthfile = NULL;
 303         *_proto = proto;
 304         *_data = data;
 305         proto[0] = data[0] = '\0';
 306
 307         if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
 308                 debug("No xauth program.");
 309         } else {
 310                 if (display == NULL) {
 311                         debug("x11_get_proto: DISPLAY not set");
 312                         return;
 313                 }
 314                 /*
 315                  * Handle FamilyLocal case where $DISPLAY does
 316                  * not match an authorization entry.  For this we
 317                  * just try "xauth list unix:displaynum.screennum".
 318                  * XXX: "localhost" match to determine FamilyLocal
 319                  *      is not perfect.
 320                  */
 321                 if (strncmp(display, "localhost:", 10) == 0) {
 322                         snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
 323                             display + 10);
 324                         display = xdisplay;
 325                 }
 326                 if (trusted == 0) {
 327                         xauthdir = xmalloc(MAXPATHLEN);
 328                         xauthfile = xmalloc(MAXPATHLEN);
 329                         mktemp_proto(xauthdir, MAXPATHLEN);
 330                         if (mkdtemp(xauthdir) != NULL) {
 331                                 do_unlink = 1;
 332                                 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
 333                                     xauthdir);
 334                                 snprintf(cmd, sizeof(cmd),
 335                                     "%s -f %s generate %s " SSH_X11_PROTO
 336                                     " untrusted timeout %u 2>" _PATH_DEVNULL,
 337                                     xauth_path, xauthfile, display, timeout);
 338                                 debug2("x11_get_proto: %s", cmd);
 339                                 if (system(cmd) == 0)
 340                                         generated = 1;
 341                                 if (x11_refuse_time == 0) {
 342                                         now = time(NULL) + 1;
 343                                         if (UINT_MAX - timeout < now)
 344                                                 x11_refuse_time = UINT_MAX;
 345                                         else
 346                                                 x11_refuse_time = now + timeout;
 347                                 }
 348                         }
 349                 }
 350
 351                 /*
 352                  * When in untrusted mode, we read the cookie only if it was
 353                  * successfully generated as an untrusted one in the step
 354                  * above.
 355                  */
 356                 if (trusted || generated) {
 357                         snprintf(cmd, sizeof(cmd),
 358                             "%s %s%s list %s 2>" _PATH_DEVNULL,
 359                             xauth_path,
 360                             generated ? "-f " : "" ,
 361                             generated ? xauthfile : "",
 362                             display);
 363                         debug2("x11_get_proto: %s", cmd);
 364                         f = popen(cmd, "r");
 365                         if (f && fgets(line, sizeof(line), f) &&
 366                             sscanf(line, "%*s %511s %511s", proto, data) == 2)
 367                                 got_data = 1;
 368                         if (f)
 369                                 pclose(f);
 370                 } else
 371                         error("Warning: untrusted X11 forwarding setup failed: "
 372                             "xauth key data not generated");
 373         }
 374
 375         if (do_unlink) {
 376                 unlink(xauthfile);
 377                 rmdir(xauthdir);
 378         }
 379         if (xauthdir)
 380                 xfree(xauthdir);
 381         if (xauthfile)
 382                 xfree(xauthfile);
 383
 384         /*
 385          * If we didn't get authentication data, just make up some
 386          * data.  The forwarding code will check the validity of the
 387          * response anyway, and substitute this data.  The X11
 388          * server, however, will ignore this fake data and use
 389          * whatever authentication mechanisms it was using otherwise
 390          * for the local connection.
 391          */
 392         if (!got_data) {
 393                 u_int32_t rnd = 0;
 394
 395                 logit("Warning: No xauth data; "
 396                     "using fake authentication data for X11 forwarding.");
 397                 strlcpy(proto, SSH_X11_PROTO, sizeof proto);
 398                 for (i = 0; i < 16; i++) {
 399                         if (i % 4 == 0)
 400                                 rnd = arc4random();
 401                         snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
 402                             rnd & 0xff);
 403                         rnd >>= 8;
 404                 }
 405         }
 406 }
 407
 408 /*
 409  * This is called when the interactive is entered.  This checks if there is
 410  * an EOF coming on stdin.  We must check this explicitly, as select() does
 411  * not appear to wake up when redirecting from /dev/null.
 412  */
 413
 414 static void
 415 client_check_initial_eof_on_stdin(void)
 416 {
 417         int len;
 418         char buf[1];
 419
 420         /*
 421          * If standard input is to be "redirected from /dev/null", we simply
 422          * mark that we have seen an EOF and send an EOF message to the
 423          * server. Otherwise, we try to read a single character; it appears
 424          * that for some files, such /dev/null, select() never wakes up for
 425          * read for this descriptor, which means that we never get EOF.  This
 426          * way we will get the EOF if stdin comes from /dev/null or similar.
 427          */
 428         if (stdin_null_flag) {
 429                 /* Fake EOF on stdin. */
 430                 debug("Sending eof.");
 431                 stdin_eof = 1;
 432                 packet_start(SSH_CMSG_EOF);
 433                 packet_send();
 434         } else {
 435                 enter_non_blocking();
 436
 437                 /* Check for immediate EOF on stdin. */
 438                 len = read(fileno(stdin), buf, 1);
 439                 if (len == 0) {
 440                         /*
 441                          * EOF.  Record that we have seen it and send
 442                          * EOF to server.
 443                          */
 444                         debug("Sending eof.");
 445                         stdin_eof = 1;
 446                         packet_start(SSH_CMSG_EOF);
 447                         packet_send();
 448                 } else if (len > 0) {
 449                         /*
 450                          * Got data.  We must store the data in the buffer,
 451                          * and also process it as an escape character if
 452                          * appropriate.
 453                          */
 454                         if ((u_char) buf[0] == escape_char1)
 455                                 escape_pending1 = 1;
 456                         else
 457                                 buffer_append(&stdin_buffer, buf, 1);
 458                 }
 459                 leave_non_blocking();
 460         }
 461 }
 462
 463
 464 /*
 465  * Make packets from buffered stdin data, and buffer them for sending to the
 466  * connection.
 467  */
 468
 469 static void
 470 client_make_packets_from_stdin_data(void)
 471 {
 472         u_int len;
 473
 474         /* Send buffered stdin data to the server. */
 475         while (buffer_len(&stdin_buffer) > 0 &&
 476             packet_not_very_much_data_to_write()) {
 477                 len = buffer_len(&stdin_buffer);
 478                 /* Keep the packets at reasonable size. */
 479                 if (len > packet_get_maxsize())
 480                         len = packet_get_maxsize();
 481                 packet_start(SSH_CMSG_STDIN_DATA);
 482                 packet_put_string(buffer_ptr(&stdin_buffer), len);
 483                 packet_send();
 484                 buffer_consume(&stdin_buffer, len);
 485                 /* If we have a pending EOF, send it now. */
 486                 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
 487                         packet_start(SSH_CMSG_EOF);
 488                         packet_send();
 489                 }
 490         }
 491 }
 492
 493 /*
 494  * Checks if the client window has changed, and sends a packet about it to
 495  * the server if so.  The actual change is detected elsewhere (by a software
 496  * interrupt on Unix); this just checks the flag and sends a message if
 497  * appropriate.
 498  */
 499
 500 static void
 501 client_check_window_change(void)
 502 {
 503         struct winsize ws;
 504
 505         if (! received_window_change_signal)
 506                 return;
 507         /** XXX race */
 508         received_window_change_signal = 0;
 509
 510         debug2("client_check_window_change: changed");
 511
 512         if (compat20) {
 513                 channel_send_window_changes();
 514         } else {
 515                 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
 516                         return;
 517                 packet_start(SSH_CMSG_WINDOW_SIZE);
 518                 packet_put_int((u_int)ws.ws_row);
 519                 packet_put_int((u_int)ws.ws_col);
 520                 packet_put_int((u_int)ws.ws_xpixel);
 521                 packet_put_int((u_int)ws.ws_ypixel);
 522                 packet_send();
 523         }
 524 }
 525
 526 static void
 527 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
 528 {
 529         struct global_confirm *gc;
 530
 531         if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
 532                 return;
 533         if (gc->cb != NULL)
 534                 gc->cb(type, seq, gc->ctx);
 535         if (--gc->ref_count <= 0) {
 536                 TAILQ_REMOVE(&global_confirms, gc, entry);
 537                 bzero(gc, sizeof(*gc));
 538                 xfree(gc);
 539         }
 540
 541         packet_set_alive_timeouts(0);
 542 }
 543
 544 static void
 545 server_alive_check(void)
 546 {
 547         if (packet_inc_alive_timeouts() > options.server_alive_count_max) {
 548                 logit("Timeout, server %s not responding.", host);
 549                 cleanup_exit(255);
 550         }
 551         packet_start(SSH2_MSG_GLOBAL_REQUEST);
 552         packet_put_cstring("keepalive@openssh.com");
 553         packet_put_char(1);     /* boolean: want reply */
 554         packet_send();
 555         /* Insert an empty placeholder to maintain ordering */
 556         client_register_global_confirm(NULL, NULL);
 557 }
 558
 559 /*
 560  * Waits until the client can do something (some data becomes available on
 561  * one of the file descriptors).
 562  */
 563 static void
 564 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
 565     int *maxfdp, u_int *nallocp, int rekeying)
 566 {
 567         struct timeval tv, *tvp;
 568         int timeout_secs;
 569         int ret;
 570
 571         /* Add any selections by the channel mechanism. */
 572         channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
 573
 574         if (!compat20) {
 575                 /* Read from the connection, unless our buffers are full. */
 576                 if (buffer_len(&stdout_buffer) < buffer_high &&
 577                     buffer_len(&stderr_buffer) < buffer_high &&
 578                     channel_not_very_much_buffered_data())
 579                         FD_SET(connection_in, *readsetp);
 580                 /*
 581                  * Read from stdin, unless we have seen EOF or have very much
 582                  * buffered data to send to the server.
 583                  */
 584                 if (!stdin_eof && packet_not_very_much_data_to_write())
 585                         FD_SET(fileno(stdin), *readsetp);
 586
 587                 /* Select stdout/stderr if have data in buffer. */
 588                 if (buffer_len(&stdout_buffer) > 0)
 589                         FD_SET(fileno(stdout), *writesetp);
 590                 if (buffer_len(&stderr_buffer) > 0)
 591                         FD_SET(fileno(stderr), *writesetp);
 592         } else {
 593                 /* channel_prepare_select could have closed the last channel */
 594                 if (session_closed && !channel_still_open() &&
 595                     !packet_have_data_to_write()) {
 596                         /* clear mask since we did not call select() */
 597                         memset(*readsetp, 0, *nallocp);
 598                         memset(*writesetp, 0, *nallocp);
 599                         return;
 600                 } else {
 601                         FD_SET(connection_in, *readsetp);
 602                 }
 603         }
 604
 605         /* Select server connection if have data to write to the server. */
 606         if (packet_have_data_to_write())
 607                 FD_SET(connection_out, *writesetp);
 608
 609         /*
 610          * Wait for something to happen.  This will suspend the process until
 611          * some selected descriptor can be read, written, or has some other
 612          * event pending, or a timeout expires.
 613          */
 614
 615         timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */
 616         if (options.server_alive_interval > 0 && compat20)
 617                 timeout_secs = options.server_alive_interval;
 618         set_control_persist_exit_time();
 619         if (control_persist_exit_time > 0) {
 620                 timeout_secs = MIN(timeout_secs,
 621                         control_persist_exit_time - time(NULL));
 622                 if (timeout_secs < 0)
 623                         timeout_secs = 0;
 624         }
 625         if (timeout_secs == INT_MAX)
 626                 tvp = NULL;
 627         else {
 628                 tv.tv_sec = timeout_secs;
 629                 tv.tv_usec = 0;
 630                 tvp = &tv;
 631         }
 632
 633         ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
 634         if (ret < 0) {
 635                 char buf[100];
 636
 637                 /*
 638                  * We have to clear the select masks, because we return.
 639                  * We have to return, because the mainloop checks for the flags
 640                  * set by the signal handlers.
 641                  */
 642                 memset(*readsetp, 0, *nallocp);
 643                 memset(*writesetp, 0, *nallocp);
 644
 645                 if (errno == EINTR)
 646                         return;
 647                 /* Note: we might still have data in the buffers. */
 648                 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
 649                 buffer_append(&stderr_buffer, buf, strlen(buf));
 650                 quit_pending = 1;
 651         } else if (ret == 0)
 652                 server_alive_check();
 653 }
 654
 655 static void
 656 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
 657 {
 658         /* Flush stdout and stderr buffers. */
 659         if (buffer_len(bout) > 0)
 660                 atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
 661                     buffer_len(bout));
 662         if (buffer_len(berr) > 0)
 663                 atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
 664                     buffer_len(berr));
 665
 666         leave_raw_mode(force_tty_flag);
 667
 668         /*
 669          * Free (and clear) the buffer to reduce the amount of data that gets
 670          * written to swap.
 671          */
 672         buffer_free(bin);
 673         buffer_free(bout);
 674         buffer_free(berr);
 675
 676         /* Send the suspend signal to the program itself. */
 677         kill(getpid(), SIGTSTP);
 678
 679         /* Reset window sizes in case they have changed */
 680         received_window_change_signal = 1;
 681
 682         /* OK, we have been continued by the user. Reinitialize buffers. */
 683         buffer_init(bin);
 684         buffer_init(bout);
 685         buffer_init(berr);
 686
 687         enter_raw_mode(force_tty_flag);
 688 }
 689
 690 static void
 691 client_process_net_input(fd_set *readset)
 692 {
 693         int len, cont = 0;
 694         char buf[SSH_IOBUFSZ];
 695
 696         /*
 697          * Read input from the server, and add any such data to the buffer of
 698          * the packet subsystem.
 699          */
 700         if (FD_ISSET(connection_in, readset)) {
 701                 /* Read as much as possible. */
 702                 len = roaming_read(connection_in, buf, sizeof(buf), &cont);
 703                 if (len == 0 && cont == 0) {
 704                         /*
 705                          * Received EOF.  The remote host has closed the
 706                          * connection.
 707                          */
 708                         snprintf(buf, sizeof buf,
 709                             "Connection to %.300s closed by remote host.\r\n",
 710                             host);
 711                         buffer_append(&stderr_buffer, buf, strlen(buf));
 712                         quit_pending = 1;
 713                         return;
 714                 }
 715                 /*
 716                  * There is a kernel bug on Solaris that causes select to
 717                  * sometimes wake up even though there is no data available.
 718                  */
 719                 if (len < 0 &&
 720                     (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
 721                         len = 0;
 722
 723                 if (len < 0) {
 724                         /*
 725                          * An error has encountered.  Perhaps there is a
 726                          * network problem.
 727                          */
 728                         snprintf(buf, sizeof buf,
 729                             "Read from remote host %.300s: %.100s\r\n",
 730                             host, strerror(errno));
 731                         buffer_append(&stderr_buffer, buf, strlen(buf));
 732                         quit_pending = 1;
 733                         return;
 734                 }
 735                 packet_process_incoming(buf, len);
 736         }
 737 }
 738
 739 static void
 740 client_status_confirm(int type, Channel *c, void *ctx)
 741 {
 742         struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
 743         char errmsg[256];
 744         int tochan;
 745
 746         /* XXX supress on mux _client_ quietmode */
 747         tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
 748             c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
 749
 750         if (type == SSH2_MSG_CHANNEL_SUCCESS) {
 751                 debug2("%s request accepted on channel %d",
 752                     cr->request_type, c->self);
 753         } else if (type == SSH2_MSG_CHANNEL_FAILURE) {
 754                 if (tochan) {
 755                         snprintf(errmsg, sizeof(errmsg),
 756                             "%s request failed\r\n", cr->request_type);
 757                 } else {
 758                         snprintf(errmsg, sizeof(errmsg),
 759                             "%s request failed on channel %d",
 760                             cr->request_type, c->self);
 761                 }
 762                 /* If error occurred on primary session channel, then exit */
 763                 if (cr->do_close && c->self == session_ident)
 764                         fatal("%s", errmsg);
 765                 /* If error occurred on mux client, append to their stderr */
 766                 if (tochan)
 767                         buffer_append(&c->extended, errmsg, strlen(errmsg));
 768                 else
 769                         error("%s", errmsg);
 770                 if (cr->do_close) {
 771                         chan_read_failed(c);
 772                         chan_write_failed(c);
 773                 }
 774         }
 775         xfree(cr);
 776 }
 777
 778 static void
 779 client_abandon_status_confirm(Channel *c, void *ctx)
 780 {
 781         xfree(ctx);
 782 }
 783
 784 static void
 785 client_expect_confirm(int id, const char *request, int do_close)
 786 {
 787         struct channel_reply_ctx *cr = xmalloc(sizeof(*cr));
 788
 789         cr->request_type = request;
 790         cr->do_close = do_close;
 791
 792         channel_register_status_confirm(id, client_status_confirm,
 793             client_abandon_status_confirm, cr);
 794 }
 795
 796 void
 797 client_register_global_confirm(global_confirm_cb *cb, void *ctx)
 798 {
 799         struct global_confirm *gc, *last_gc;
 800
 801         /* Coalesce identical callbacks */
 802         last_gc = TAILQ_LAST(&global_confirms, global_confirms);
 803         if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
 804                 if (++last_gc->ref_count >= INT_MAX)
 805                         fatal("%s: last_gc->ref_count = %d",
 806                             __func__, last_gc->ref_count);
 807                 return;
 808         }
 809
 810         gc = xmalloc(sizeof(*gc));
 811         gc->cb = cb;
 812         gc->ctx = ctx;
 813         gc->ref_count = 1;
 814         TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
 815 }
 816
 817 static void
 818 process_cmdline(void)
 819 {
 820         void (*handler)(int);
 821         char *s, *cmd, *cancel_host;
 822         int delete = 0;
 823         int local = 0, remote = 0, dynamic = 0;
 824         int cancel_port;
 825         Forward fwd;
 826
 827         bzero(&fwd, sizeof(fwd));
 828         fwd.listen_host = fwd.connect_host = NULL;
 829
 830         leave_raw_mode(force_tty_flag);
 831         handler = signal(SIGINT, SIG_IGN);
 832         cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
 833         if (s == NULL)
 834                 goto out;
 835         while (isspace(*s))
 836                 s++;
 837         if (*s == '-')
 838                 s++;    /* Skip cmdline '-', if any */
 839         if (*s == '\0')
 840                 goto out;
 841
 842         if (*s == 'h' || *s == 'H' || *s == '?') {
 843                 logit("Commands:");
 844                 logit("      -L[bind_address:]port:host:hostport    "
 845                     "Request local forward");
 846                 logit("      -R[bind_address:]port:host:hostport    "
 847                     "Request remote forward");
 848                 logit("      -D[bind_address:]port                  "
 849                     "Request dynamic forward");
 850                 logit("      -KR[bind_address:]port                 "
 851                     "Cancel remote forward");
 852                 if (!options.permit_local_command)
 853                         goto out;
 854                 logit("      !args                                  "
 855                     "Execute local command");
 856                 goto out;
 857         }
 858
 859         if (*s == '!' && options.permit_local_command) {
 860                 s++;
 861                 ssh_local_cmd(s);
 862                 goto out;
 863         }
 864
 865         if (*s == 'K') {
 866                 delete = 1;
 867                 s++;
 868         }
 869         if (*s == 'L')
 870                 local = 1;
 871         else if (*s == 'R')
 872                 remote = 1;
 873         else if (*s == 'D')
 874                 dynamic = 1;
 875         else {
 876                 logit("Invalid command.");
 877                 goto out;
 878         }
 879
 880         if ((local || dynamic) && delete) {
 881                 logit("Not supported.");
 882                 goto out;
 883         }
 884         if (remote && delete && !compat20) {
 885                 logit("Not supported for SSH protocol version 1.");
 886                 goto out;
 887         }
 888
 889         while (isspace(*++s))
 890                 ;
 891
 892         /* XXX update list of forwards in options */
 893         if (delete) {
 894                 cancel_port = 0;
 895                 cancel_host = hpdelim(&s);      /* may be NULL */
 896                 if (s != NULL) {
 897                         cancel_port = a2port(s);
 898                         cancel_host = cleanhostname(cancel_host);
 899                 } else {
 900                         cancel_port = a2port(cancel_host);
 901                         cancel_host = NULL;
 902                 }
 903                 if (cancel_port <= 0) {
 904                         logit("Bad forwarding close port");
 905                         goto out;
 906                 }
 907                 channel_request_rforward_cancel(cancel_host, cancel_port);
 908         } else {
 909                 if (!parse_forward(&fwd, s, dynamic, remote)) {
 910                         logit("Bad forwarding specification.");
 911                         goto out;
 912                 }
 913                 if (local || dynamic) {
 914                         if (channel_setup_local_fwd_listener(fwd.listen_host,
 915                             fwd.listen_port, fwd.connect_host,
 916                             fwd.connect_port, options.gateway_ports) < 0) {
 917                                 logit("Port forwarding failed.");
 918                                 goto out;
 919                         }
 920                 } else {
 921                         if (channel_request_remote_forwarding(fwd.listen_host,
 922                             fwd.listen_port, fwd.connect_host,
 923                             fwd.connect_port) < 0) {
 924                                 logit("Port forwarding failed.");
 925                                 goto out;
 926                         }
 927                 }
 928
 929                 logit("Forwarding port.");
 930         }
 931
 932 out:
 933         signal(SIGINT, handler);
 934         enter_raw_mode(force_tty_flag);
 935         if (cmd)
 936                 xfree(cmd);
 937         if (fwd.listen_host != NULL)
 938                 xfree(fwd.listen_host);
 939         if (fwd.connect_host != NULL)
 940                 xfree(fwd.connect_host);
 941 }
 942
 943 /*
 944  * Process the characters one by one, call with c==NULL for proto1 case.
 945  */
 946 static int
 947 process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
 948     char *buf, int len)
 949 {
 950         char string[1024];
 951         pid_t pid;
 952         int bytes = 0;
 953         u_int i;
 954         u_char ch;
 955         char *s;
 956         int *escape_pendingp, escape_char;
 957         struct escape_filter_ctx *efc;
 958
 959         if (c == NULL) {
 960                 escape_pendingp = &escape_pending1;
 961                 escape_char = escape_char1;
 962         } else {
 963                 if (c->filter_ctx == NULL)
 964                         return 0;
 965                 efc = (struct escape_filter_ctx *)c->filter_ctx;
 966                 escape_pendingp = &efc->escape_pending;
 967                 escape_char = efc->escape_char;
 968         }
 969
 970         if (len <= 0)
 971                 return (0);
 972
 973         for (i = 0; i < (u_int)len; i++) {
 974                 /* Get one character at a time. */
 975                 ch = buf[i];
 976
 977                 if (*escape_pendingp) {
 978                         /* We have previously seen an escape character. */
 979                         /* Clear the flag now. */
 980                         *escape_pendingp = 0;
 981
 982                         /* Process the escaped character. */
 983                         switch (ch) {
 984                         case '.':
 985                                 /* Terminate the connection. */
 986                                 snprintf(string, sizeof string, "%c.\r\n",
 987                                     escape_char);
 988                                 buffer_append(berr, string, strlen(string));
 989
 990                                 if (c && c->ctl_chan != -1) {
 991                                         chan_read_failed(c);
 992                                         chan_write_failed(c);
 993                                         return 0;
 994                                 } else
 995                                         quit_pending = 1;
 996                                 return -1;
 997
 998                         case 'Z' - 64:
 999                                 /* XXX support this for mux clients */
1000                                 if (c && c->ctl_chan != -1) {
1001  noescape:
1002                                         snprintf(string, sizeof string,
1003                                             "%c%c escape not available to "
1004                                             "multiplexed sessions\r\n",
1005                                             escape_char, ch);
1006                                         buffer_append(berr, string,
1007                                             strlen(string));
1008                                         continue;
1009                                 }
1010                                 /* Suspend the program. Inform the user */
1011                                 snprintf(string, sizeof string,
1012                                     "%c^Z [suspend ssh]\r\n", escape_char);
1013                                 buffer_append(berr, string, strlen(string));
1014
1015                                 /* Restore terminal modes and suspend. */
1016                                 client_suspend_self(bin, bout, berr);
1017
1018                                 /* We have been continued. */
1019                                 continue;
1020
1021                         case 'B':
1022                                 if (compat20) {
1023                                         snprintf(string, sizeof string,
1024                                             "%cB\r\n", escape_char);
1025                                         buffer_append(berr, string,
1026                                             strlen(string));
1027                                         channel_request_start(session_ident,
1028                                             "break", 0);
1029                                         packet_put_int(1000);
1030                                         packet_send();
1031                                 }
1032                                 continue;
1033
1034                         case 'R':
1035                                 if (compat20) {
1036                                         if (datafellows & SSH_BUG_NOREKEY)
1037                                                 logit("Server does not "
1038                                                     "support re-keying");
1039                                         else
1040                                                 need_rekeying = 1;
1041                                 }
1042                                 continue;
1043
1044                         case '&':
1045                                 if (c && c->ctl_chan != -1)
1046                                         goto noescape;
1047                                 /*
1048                                  * Detach the program (continue to serve
1049                                  * connections, but put in background and no
1050                                  * more new connections).
1051                                  */
1052                                 /* Restore tty modes. */
1053                                 leave_raw_mode(force_tty_flag);
1054
1055                                 /* Stop listening for new connections. */
1056                                 channel_stop_listening();
1057
1058                                 snprintf(string, sizeof string,
1059                                     "%c& [backgrounded]\n", escape_char);
1060                                 buffer_append(berr, string, strlen(string));
1061
1062                                 /* Fork into background. */
1063                                 pid = fork();
1064                                 if (pid < 0) {
1065                                         error("fork: %.100s", strerror(errno));
1066                                         continue;
1067                                 }
1068                                 if (pid != 0) { /* This is the parent. */
1069                                         /* The parent just exits. */
1070                                         exit(0);
1071                                 }
1072                                 /* The child continues serving connections. */
1073                                 if (compat20) {
1074                                         buffer_append(bin, "\004", 1);
1075                                         /* fake EOF on stdin */
1076                                         return -1;
1077                                 } else if (!stdin_eof) {
1078                                         /*
1079                                          * Sending SSH_CMSG_EOF alone does not
1080                                          * always appear to be enough.  So we
1081                                          * try to send an EOF character first.
1082                                          */
1083                                         packet_start(SSH_CMSG_STDIN_DATA);
1084                                         packet_put_string("\004", 1);
1085                                         packet_send();
1086                                         /* Close stdin. */
1087                                         stdin_eof = 1;
1088                                         if (buffer_len(bin) == 0) {
1089                                                 packet_start(SSH_CMSG_EOF);
1090                                                 packet_send();
1091                                         }
1092                                 }
1093                                 continue;
1094
1095                         case '?':
1096                                 if (c && c->ctl_chan != -1) {
1097                                         snprintf(string, sizeof string,
1098 "%c?\r\n\
1099 Supported escape sequences:\r\n\
1100   %c.  - terminate session\r\n\
1101   %cB  - send a BREAK to the remote system\r\n\
1102   %cR  - Request rekey (SSH protocol 2 only)\r\n\
1103   %c#  - list forwarded connections\r\n\
1104   %c?  - this message\r\n\
1105   %c%c  - send the escape character by typing it twice\r\n\
1106 (Note that escapes are only recognized immediately after newline.)\r\n",
1107                                             escape_char, escape_char,
1108                                             escape_char, escape_char,
1109                                             escape_char, escape_char,
1110                                             escape_char, escape_char);
1111                                 } else {
1112                                         snprintf(string, sizeof string,
1113 "%c?\r\n\
1114 Supported escape sequences:\r\n\
1115   %c.  - terminate connection (and any multiplexed sessions)\r\n\
1116   %cB  - send a BREAK to the remote system\r\n\
1117   %cC  - open a command line\r\n\
1118   %cR  - Request rekey (SSH protocol 2 only)\r\n\
1119   %c^Z - suspend ssh\r\n\
1120   %c#  - list forwarded connections\r\n\
1121   %c&  - background ssh (when waiting for connections to terminate)\r\n\
1122   %c?  - this message\r\n\
1123   %c%c  - send the escape character by typing it twice\r\n\
1124 (Note that escapes are only recognized immediately after newline.)\r\n",
1125                                             escape_char, escape_char,
1126                                             escape_char, escape_char,
1127                                             escape_char, escape_char,
1128                                             escape_char, escape_char,
1129                                             escape_char, escape_char,
1130                                             escape_char);
1131                                 }
1132                                 buffer_append(berr, string, strlen(string));
1133                                 continue;
1134
1135                         case '#':
1136                                 snprintf(string, sizeof string, "%c#\r\n",
1137                                     escape_char);
1138                                 buffer_append(berr, string, strlen(string));
1139                                 s = channel_open_message();
1140                                 buffer_append(berr, s, strlen(s));
1141                                 xfree(s);
1142                                 continue;
1143
1144                         case 'C':
1145                                 if (c && c->ctl_chan != -1)
1146                                         goto noescape;
1147                                 process_cmdline();
1148                                 continue;
1149
1150                         default:
1151                                 if (ch != escape_char) {
1152                                         buffer_put_char(bin, escape_char);
1153                                         bytes++;
1154                                 }
1155                                 /* Escaped characters fall through here */
1156                                 break;
1157                         }
1158                 } else {
1159                         /*
1160                          * The previous character was not an escape char.
1161                          * Check if this is an escape.
1162                          */
1163                         if (last_was_cr && ch == escape_char) {
1164                                 /*
1165                                  * It is. Set the flag and continue to
1166                                  * next character.
1167                                  */
1168                                 *escape_pendingp = 1;
1169                                 continue;
1170                         }
1171                 }
1172
1173                 /*
1174                  * Normal character.  Record whether it was a newline,
1175                  * and append it to the buffer.
1176                  */
1177                 last_was_cr = (ch == '\r' || ch == '\n');
1178                 buffer_put_char(bin, ch);
1179                 bytes++;
1180         }
1181         return bytes;
1182 }
1183
1184 static void
1185 client_process_input(fd_set *readset)
1186 {
1187         int len;
1188         char buf[SSH_IOBUFSZ];
1189
1190         /* Read input from stdin. */
1191         if (FD_ISSET(fileno(stdin), readset)) {
1192                 /* Read as much as possible. */
1193                 len = read(fileno(stdin), buf, sizeof(buf));
1194                 if (len < 0 &&
1195                     (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
1196                         return;         /* we'll try again later */
1197                 if (len <= 0) {
1198                         /*
1199                          * Received EOF or error.  They are treated
1200                          * similarly, except that an error message is printed
1201                          * if it was an error condition.
1202                          */
1203                         if (len < 0) {
1204                                 snprintf(buf, sizeof buf, "read: %.100s\r\n",
1205                                     strerror(errno));
1206                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1207                         }
1208                         /* Mark that we have seen EOF. */
1209                         stdin_eof = 1;
1210                         /*
1211                          * Send an EOF message to the server unless there is
1212                          * data in the buffer.  If there is data in the
1213                          * buffer, no message will be sent now.  Code
1214                          * elsewhere will send the EOF when the buffer
1215                          * becomes empty if stdin_eof is set.
1216                          */
1217                         if (buffer_len(&stdin_buffer) == 0) {
1218                                 packet_start(SSH_CMSG_EOF);
1219                                 packet_send();
1220                         }
1221                 } else if (escape_char1 == SSH_ESCAPECHAR_NONE) {
1222                         /*
1223                          * Normal successful read, and no escape character.
1224                          * Just append the data to buffer.
1225                          */
1226                         buffer_append(&stdin_buffer, buf, len);
1227                 } else {
1228                         /*
1229                          * Normal, successful read.  But we have an escape
1230                          * character and have to process the characters one
1231                          * by one.
1232                          */
1233                         if (process_escapes(NULL, &stdin_buffer,
1234                             &stdout_buffer, &stderr_buffer, buf, len) == -1)
1235                                 return;
1236                 }
1237         }
1238 }
1239
1240 static void
1241 client_process_output(fd_set *writeset)
1242 {
1243         int len;
1244         char buf[100];
1245
1246         /* Write buffered output to stdout. */
1247         if (FD_ISSET(fileno(stdout), writeset)) {
1248                 /* Write as much data as possible. */
1249                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1250                     buffer_len(&stdout_buffer));
1251                 if (len <= 0) {
1252                         if (errno == EINTR || errno == EAGAIN ||
1253                             errno == EWOULDBLOCK)
1254                                 len = 0;
1255                         else {
1256                                 /*
1257                                  * An error or EOF was encountered.  Put an
1258                                  * error message to stderr buffer.
1259                                  */
1260                                 snprintf(buf, sizeof buf,
1261                                     "write stdout: %.50s\r\n", strerror(errno));
1262                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1263                                 quit_pending = 1;
1264                                 return;
1265                         }
1266                 }
1267                 /* Consume printed data from the buffer. */
1268                 buffer_consume(&stdout_buffer, len);
1269         }
1270         /* Write buffered output to stderr. */
1271         if (FD_ISSET(fileno(stderr), writeset)) {
1272                 /* Write as much data as possible. */
1273                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1274                     buffer_len(&stderr_buffer));
1275                 if (len <= 0) {
1276                         if (errno == EINTR || errno == EAGAIN ||
1277                             errno == EWOULDBLOCK)
1278                                 len = 0;
1279                         else {
1280                                 /*
1281                                  * EOF or error, but can't even print
1282                                  * error message.
1283                                  */
1284                                 quit_pending = 1;
1285                                 return;
1286                         }
1287                 }
1288                 /* Consume printed characters from the buffer. */
1289                 buffer_consume(&stderr_buffer, len);
1290         }
1291 }
1292
1293 /*
1294  * Get packets from the connection input buffer, and process them as long as
1295  * there are packets available.
1296  *
1297  * Any unknown packets received during the actual
1298  * session cause the session to terminate.  This is
1299  * intended to make debugging easier since no
1300  * confirmations are sent.  Any compatible protocol
1301  * extensions must be negotiated during the
1302  * preparatory phase.
1303  */
1304
1305 static void
1306 client_process_buffered_input_packets(void)
1307 {
1308         dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
1309             compat20 ? xxx_kex : NULL);
1310 }
1311
1312 /* scan buf[] for '~' before sending data to the peer */
1313
1314 /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1315 void *
1316 client_new_escape_filter_ctx(int escape_char)
1317 {
1318         struct escape_filter_ctx *ret;
1319
1320         ret = xmalloc(sizeof(*ret));
1321         ret->escape_pending = 0;
1322         ret->escape_char = escape_char;
1323         return (void *)ret;
1324 }
1325
1326 /* Free the escape filter context on channel free */
1327 void
1328 client_filter_cleanup(int cid, void *ctx)
1329 {
1330         xfree(ctx);
1331 }
1332
1333 int
1334 client_simple_escape_filter(Channel *c, char *buf, int len)
1335 {
1336         if (c->extended_usage != CHAN_EXTENDED_WRITE)
1337                 return 0;
1338
1339         return process_escapes(c, &c->input, &c->output, &c->extended,
1340             buf, len);
1341 }
1342
1343 static void
1344 client_channel_closed(int id, void *arg)
1345 {
1346         channel_cancel_cleanup(id);
1347         session_closed = 1;
1348         leave_raw_mode(force_tty_flag);
1349 }
1350
1351 /*
1352  * Implements the interactive session with the server.  This is called after
1353  * the user has been authenticated, and a command has been started on the
1354  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1355  * used as an escape character for terminating or suspending the session.
1356  */
1357
1358 int
1359 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1360 {
1361         fd_set *readset = NULL, *writeset = NULL;
1362         double start_time, total_time;
1363         int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1364         u_int64_t ibytes, obytes;
1365         u_int nalloc = 0;
1366         char buf[100];
1367
1368         debug("Entering interactive session.");
1369
1370         start_time = get_current_time();
1371
1372         /* Initialize variables. */
1373         escape_pending1 = 0;
1374         last_was_cr = 1;
1375         exit_status = -1;
1376         stdin_eof = 0;
1377         buffer_high = 64 * 1024;
1378         connection_in = packet_get_connection_in();
1379         connection_out = packet_get_connection_out();
1380         max_fd = MAX(connection_in, connection_out);
1381
1382         if (!compat20) {
1383                 /* enable nonblocking unless tty */
1384                 if (!isatty(fileno(stdin)))
1385                         set_nonblock(fileno(stdin));
1386                 if (!isatty(fileno(stdout)))
1387                         set_nonblock(fileno(stdout));
1388                 if (!isatty(fileno(stderr)))
1389                         set_nonblock(fileno(stderr));
1390                 max_fd = MAX(max_fd, fileno(stdin));
1391                 max_fd = MAX(max_fd, fileno(stdout));
1392                 max_fd = MAX(max_fd, fileno(stderr));
1393         }
1394         quit_pending = 0;
1395         escape_char1 = escape_char_arg;
1396
1397         /* Initialize buffers. */
1398         buffer_init(&stdin_buffer);
1399         buffer_init(&stdout_buffer);
1400         buffer_init(&stderr_buffer);
1401
1402         client_init_dispatch();
1403
1404         /*
1405          * Set signal handlers, (e.g. to restore non-blocking mode)
1406          * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1407          */
1408         if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1409                 signal(SIGHUP, signal_handler);
1410         if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1411                 signal(SIGINT, signal_handler);
1412         if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1413                 signal(SIGQUIT, signal_handler);
1414         if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1415                 signal(SIGTERM, signal_handler);
1416         signal(SIGWINCH, window_change_handler);
1417
1418         if (have_pty)
1419                 enter_raw_mode(force_tty_flag);
1420
1421         if (compat20) {
1422                 session_ident = ssh2_chan_id;
1423                 if (escape_char_arg != SSH_ESCAPECHAR_NONE)
1424                         channel_register_filter(session_ident,
1425                             client_simple_escape_filter, NULL,
1426                             client_filter_cleanup,
1427                             client_new_escape_filter_ctx(escape_char_arg));
1428                 if (session_ident != -1)
1429                         channel_register_cleanup(session_ident,
1430                             client_channel_closed, 0);
1431         } else {
1432                 /* Check if we should immediately send eof on stdin. */
1433                 client_check_initial_eof_on_stdin();
1434         }
1435
1436         /* Main loop of the client for the interactive session mode. */
1437         while (!quit_pending) {
1438
1439                 /* Process buffered packets sent by the server. */
1440                 client_process_buffered_input_packets();
1441
1442                 if (compat20 && session_closed && !channel_still_open())
1443                         break;
1444
1445                 rekeying = (xxx_kex != NULL && !xxx_kex->done);
1446
1447                 if (rekeying) {
1448                         debug("rekeying in progress");
1449                 } else {
1450                         /*
1451                          * Make packets of buffered stdin data, and buffer
1452                          * them for sending to the server.
1453                          */
1454                         if (!compat20)
1455                                 client_make_packets_from_stdin_data();
1456
1457                         /*
1458                          * Make packets from buffered channel data, and
1459                          * enqueue them for sending to the server.
1460                          */
1461                         if (packet_not_very_much_data_to_write())
1462                                 channel_output_poll();
1463
1464                         /*
1465                          * Check if the window size has changed, and buffer a
1466                          * message about it to the server if so.
1467                          */
1468                         client_check_window_change();
1469
1470                         if (quit_pending)
1471                                 break;
1472                 }
1473                 /*
1474                  * Wait until we have something to do (something becomes
1475                  * available on one of the descriptors).
1476                  */
1477                 max_fd2 = max_fd;
1478                 client_wait_until_can_do_something(&readset, &writeset,
1479                     &max_fd2, &nalloc, rekeying);
1480
1481                 if (quit_pending)
1482                         break;
1483
1484                 /* Do channel operations unless rekeying in progress. */
1485                 if (!rekeying) {
1486                         channel_after_select(readset, writeset);
1487                         if (need_rekeying || packet_need_rekeying()) {
1488                                 debug("need rekeying");
1489                                 xxx_kex->done = 0;
1490                                 kex_send_kexinit(xxx_kex);
1491                                 need_rekeying = 0;
1492                         }
1493                 }
1494
1495                 /* Buffer input from the connection.  */
1496                 client_process_net_input(readset);
1497
1498                 if (quit_pending)
1499                         break;
1500
1501                 if (!compat20) {
1502                         /* Buffer data from stdin */
1503                         client_process_input(readset);
1504                         /*
1505                          * Process output to stdout and stderr.  Output to
1506                          * the connection is processed elsewhere (above).
1507                          */
1508                         client_process_output(writeset);
1509                 }
1510
1511                 if (session_resumed) {
1512                         connection_in = packet_get_connection_in();
1513                         connection_out = packet_get_connection_out();
1514                         max_fd = MAX(max_fd, connection_out);
1515                         max_fd = MAX(max_fd, connection_in);
1516                         session_resumed = 0;
1517                 }
1518
1519                 /*
1520                  * Send as much buffered packet data as possible to the
1521                  * sender.
1522                  */
1523                 if (FD_ISSET(connection_out, writeset))
1524                         packet_write_poll();
1525
1526                 /*
1527                  * If we are a backgrounded control master, and the
1528                  * timeout has expired without any active client
1529                  * connections, then quit.
1530                  */
1531                 if (control_persist_exit_time > 0) {
1532                         if (time(NULL) >= control_persist_exit_time) {
1533                                 debug("ControlPersist timeout expired");
1534                                 break;
1535                         }
1536                 }
1537         }
1538         if (readset)
1539                 xfree(readset);
1540         if (writeset)
1541                 xfree(writeset);
1542
1543         /* Terminate the session. */
1544
1545         /* Stop watching for window change. */
1546         signal(SIGWINCH, SIG_DFL);
1547
1548         if (compat20) {
1549                 packet_start(SSH2_MSG_DISCONNECT);
1550                 packet_put_int(SSH2_DISCONNECT_BY_APPLICATION);
1551                 packet_put_cstring("disconnected by user");
1552                 packet_put_cstring(""); /* language tag */
1553                 packet_send();
1554                 packet_write_wait();
1555         }
1556
1557         channel_free_all();
1558
1559         if (have_pty)
1560                 leave_raw_mode(force_tty_flag);
1561
1562         /* restore blocking io */
1563         if (!isatty(fileno(stdin)))
1564                 unset_nonblock(fileno(stdin));
1565         if (!isatty(fileno(stdout)))
1566                 unset_nonblock(fileno(stdout));
1567         if (!isatty(fileno(stderr)))
1568                 unset_nonblock(fileno(stderr));
1569
1570         /*
1571          * If there was no shell or command requested, there will be no remote
1572          * exit status to be returned.  In that case, clear error code if the
1573          * connection was deliberately terminated at this end.
1574          */
1575         if (no_shell_flag && received_signal == SIGTERM) {
1576                 received_signal = 0;
1577                 exit_status = 0;
1578         }
1579
1580         if (received_signal)
1581                 fatal("Killed by signal %d.", (int) received_signal);
1582
1583         /*
1584          * In interactive mode (with pseudo tty) display a message indicating
1585          * that the connection has been closed.
1586          */
1587         if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1588                 snprintf(buf, sizeof buf,
1589                     "Connection to %.64s closed.\r\n", host);
1590                 buffer_append(&stderr_buffer, buf, strlen(buf));
1591         }
1592
1593         /* Output any buffered data for stdout. */
1594         if (buffer_len(&stdout_buffer) > 0) {
1595                 len = atomicio(vwrite, fileno(stdout),
1596                     buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer));
1597                 if (len < 0 || (u_int)len != buffer_len(&stdout_buffer))
1598                         error("Write failed flushing stdout buffer.");
1599                 else
1600                         buffer_consume(&stdout_buffer, len);
1601         }
1602
1603         /* Output any buffered data for stderr. */
1604         if (buffer_len(&stderr_buffer) > 0) {
1605                 len = atomicio(vwrite, fileno(stderr),
1606                     buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
1607                 if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
1608                         error("Write failed flushing stderr buffer.");
1609                 else
1610                         buffer_consume(&stderr_buffer, len);
1611         }
1612
1613         /* Clear and free any buffers. */
1614         memset(buf, 0, sizeof(buf));
1615         buffer_free(&stdin_buffer);
1616         buffer_free(&stdout_buffer);
1617         buffer_free(&stderr_buffer);
1618
1619         /* Report bytes transferred, and transfer rates. */
1620         total_time = get_current_time() - start_time;
1621         packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
1622         packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
1623         verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
1624             (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
1625         if (total_time > 0)
1626                 verbose("Bytes per second: sent %.1f, received %.1f",
1627                     obytes / total_time, ibytes / total_time);
1628         /* Return the exit status of the program. */
1629         debug("Exit status %d", exit_status);
1630         return exit_status;
1631 }
1632
1633 /*********/
1634
1635 static void
1636 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1637 {
1638         u_int data_len;
1639         char *data = packet_get_string(&data_len);
1640         packet_check_eom();
1641         buffer_append(&stdout_buffer, data, data_len);
1642         memset(data, 0, data_len);
1643         xfree(data);
1644 }
1645 static void
1646 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1647 {
1648         u_int data_len;
1649         char *data = packet_get_string(&data_len);
1650         packet_check_eom();
1651         buffer_append(&stderr_buffer, data, data_len);
1652         memset(data, 0, data_len);
1653         xfree(data);
1654 }
1655 static void
1656 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1657 {
1658         exit_status = packet_get_int();
1659         packet_check_eom();
1660         /* Acknowledge the exit. */
1661         packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1662         packet_send();
1663         /*
1664          * Must wait for packet to be sent since we are
1665          * exiting the loop.
1666          */
1667         packet_write_wait();
1668         /* Flag that we want to exit. */
1669         quit_pending = 1;
1670 }
1671 static void
1672 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1673 {
1674         Channel *c = NULL;
1675         int remote_id, sock;
1676
1677         /* Read the remote channel number from the message. */
1678         remote_id = packet_get_int();
1679         packet_check_eom();
1680
1681         /*
1682          * Get a connection to the local authentication agent (this may again
1683          * get forwarded).
1684          */
1685         sock = ssh_get_authentication_socket();
1686
1687         /*
1688          * If we could not connect the agent, send an error message back to
1689          * the server. This should never happen unless the agent dies,
1690          * because authentication forwarding is only enabled if we have an
1691          * agent.
1692          */
1693         if (sock >= 0) {
1694                 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1695                     -1, 0, 0, 0, "authentication agent connection", 1);
1696                 c->remote_id = remote_id;
1697                 c->force_drain = 1;
1698         }
1699         if (c == NULL) {
1700                 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1701                 packet_put_int(remote_id);
1702         } else {
1703                 /* Send a confirmation to the remote host. */
1704                 debug("Forwarding authentication connection.");
1705                 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1706                 packet_put_int(remote_id);
1707                 packet_put_int(c->self);
1708         }
1709         packet_send();
1710 }
1711
1712 static Channel *
1713 client_request_forwarded_tcpip(const char *request_type, int rchan)
1714 {
1715         Channel *c = NULL;
1716         char *listen_address, *originator_address;
1717         u_short listen_port, originator_port;
1718
1719         /* Get rest of the packet */
1720         listen_address = packet_get_string(NULL);
1721         listen_port = packet_get_int();
1722         originator_address = packet_get_string(NULL);
1723         originator_port = packet_get_int();
1724         packet_check_eom();
1725
1726         debug("client_request_forwarded_tcpip: listen %s port %d, "
1727             "originator %s port %d", listen_address, listen_port,
1728             originator_address, originator_port);
1729
1730         c = channel_connect_by_listen_address(listen_port,
1731             "forwarded-tcpip", originator_address);
1732
1733         xfree(originator_address);
1734         xfree(listen_address);
1735         return c;
1736 }
1737
1738 static Channel *
1739 client_request_x11(const char *request_type, int rchan)
1740 {
1741         Channel *c = NULL;
1742         char *originator;
1743         u_short originator_port;
1744         int sock;
1745
1746         if (!options.forward_x11) {
1747                 error("Warning: ssh server tried X11 forwarding.");
1748                 error("Warning: this is probably a break-in attempt by a "
1749                     "malicious server.");
1750                 return NULL;
1751         }
1752         if (x11_refuse_time != 0 && time(NULL) >= x11_refuse_time) {
1753                 verbose("Rejected X11 connection after ForwardX11Timeout "
1754                     "expired");
1755                 return NULL;
1756         }
1757         originator = packet_get_string(NULL);
1758         if (datafellows & SSH_BUG_X11FWD) {
1759                 debug2("buggy server: x11 request w/o originator_port");
1760                 originator_port = 0;
1761         } else {
1762                 originator_port = packet_get_int();
1763         }
1764         packet_check_eom();
1765         /* XXX check permission */
1766         debug("client_request_x11: request from %s %d", originator,
1767             originator_port);
1768         xfree(originator);
1769         sock = x11_connect_display();
1770         if (sock < 0)
1771                 return NULL;
1772         if (options.hpn_disabled)
1773                 c = channel_new("x11", SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1774                     CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1775                     0, "x11", 1);
1776         else
1777                 c = channel_new("x11", SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1778                     options.hpn_buffer_size, CHAN_X11_PACKET_DEFAULT,
1779                     0, "x11", 1);
1780         c->force_drain = 1;
1781         return c;
1782 }
1783
1784 static Channel *
1785 client_request_agent(const char *request_type, int rchan)
1786 {
1787         Channel *c = NULL;
1788         int sock;
1789
1790         if (!options.forward_agent) {
1791                 error("Warning: ssh server tried agent forwarding.");
1792                 error("Warning: this is probably a break-in attempt by a "
1793                     "malicious server.");
1794                 return NULL;
1795         }
1796         sock = ssh_get_authentication_socket();
1797         if (sock < 0)
1798                 return NULL;
1799         if (options.hpn_disabled)
1800                 c = channel_new("authentication agent connection",
1801                     SSH_CHANNEL_OPEN, sock, sock, -1,
1802                     CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1803                     "authentication agent connection", 1);
1804         else
1805                 c = channel_new("authentication agent connection",
1806                     SSH_CHANNEL_OPEN, sock, sock, -1,
1807                     options.hpn_buffer_size, options.hpn_buffer_size, 0,
1808                     "authentication agent connection", 1);
1809         c->force_drain = 1;
1810         return c;
1811 }
1812
1813 int
1814 client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
1815 {
1816         Channel *c;
1817         int fd;
1818
1819         if (tun_mode == SSH_TUNMODE_NO)
1820                 return 0;
1821
1822         if (!compat20) {
1823                 error("Tunnel forwarding is not supported for protocol 1");
1824                 return -1;
1825         }
1826
1827         debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
1828
1829         /* Open local tunnel device */
1830         if ((fd = tun_open(local_tun, tun_mode)) == -1) {
1831                 error("Tunnel device open failed.");
1832                 return -1;
1833         }
1834
1835         if (options.hpn_disabled)
1836                 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1837                     CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1838                     0, "tun", 1);
1839         else
1840                 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1841                     options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT,
1842                     0, "tun", 1);
1843         c->datagram = 1;
1844
1845 #if defined(SSH_TUN_FILTER)
1846         if (options.tun_open == SSH_TUNMODE_POINTOPOINT)
1847                 channel_register_filter(c->self, sys_tun_infilter,
1848                     sys_tun_outfilter, NULL, NULL);
1849 #endif
1850
1851         packet_start(SSH2_MSG_CHANNEL_OPEN);
1852         packet_put_cstring("tun@openssh.com");
1853         packet_put_int(c->self);
1854         packet_put_int(c->local_window_max);
1855         packet_put_int(c->local_maxpacket);
1856         packet_put_int(tun_mode);
1857         packet_put_int(remote_tun);
1858         packet_send();
1859
1860         return 0;
1861 }
1862
1863 /* XXXX move to generic input handler */
1864 static void
1865 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1866 {
1867         Channel *c = NULL;
1868         char *ctype;
1869         int rchan;
1870         u_int rmaxpack, rwindow, len;
1871
1872         ctype = packet_get_string(&len);
1873         rchan = packet_get_int();
1874         rwindow = packet_get_int();
1875         rmaxpack = packet_get_int();
1876
1877         debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1878             ctype, rchan, rwindow, rmaxpack);
1879
1880         if (strcmp(ctype, "forwarded-tcpip") == 0) {
1881                 c = client_request_forwarded_tcpip(ctype, rchan);
1882         } else if (strcmp(ctype, "x11") == 0) {
1883                 c = client_request_x11(ctype, rchan);
1884         } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1885                 c = client_request_agent(ctype, rchan);
1886         }
1887 /* XXX duplicate : */
1888         if (c != NULL) {
1889                 debug("confirm %s", ctype);
1890                 c->remote_id = rchan;
1891                 c->remote_window = rwindow;
1892                 c->remote_maxpacket = rmaxpack;
1893                 if (c->type != SSH_CHANNEL_CONNECTING) {
1894                         packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1895                         packet_put_int(c->remote_id);
1896                         packet_put_int(c->self);
1897                         packet_put_int(c->local_window);
1898                         packet_put_int(c->local_maxpacket);
1899                         packet_send();
1900                 }
1901         } else {
1902                 debug("failure %s", ctype);
1903                 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1904                 packet_put_int(rchan);
1905                 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1906                 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1907                         packet_put_cstring("open failed");
1908                         packet_put_cstring("");
1909                 }
1910                 packet_send();
1911         }
1912         xfree(ctype);
1913 }
1914 static void
1915 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1916 {
1917         Channel *c = NULL;
1918         int exitval, id, reply, success = 0;
1919         char *rtype;
1920
1921         id = packet_get_int();
1922         rtype = packet_get_string(NULL);
1923         reply = packet_get_char();
1924
1925         debug("client_input_channel_req: channel %d rtype %s reply %d",
1926             id, rtype, reply);
1927
1928         if (id == -1) {
1929                 error("client_input_channel_req: request for channel -1");
1930         } else if ((c = channel_lookup(id)) == NULL) {
1931                 error("client_input_channel_req: channel %d: "
1932                     "unknown channel", id);
1933         } else if (strcmp(rtype, "eow@openssh.com") == 0) {
1934                 packet_check_eom();
1935                 chan_rcvd_eow(c);
1936         } else if (strcmp(rtype, "exit-status") == 0) {
1937                 exitval = packet_get_int();
1938                 if (c->ctl_chan != -1) {
1939                         mux_exit_message(c, exitval);
1940                         success = 1;
1941                 } else if (id == session_ident) {
1942                         /* Record exit value of local session */
1943                         success = 1;
1944                         exit_status = exitval;
1945                 } else {
1946                         /* Probably for a mux channel that has already closed */
1947                         debug("%s: no sink for exit-status on channel %d",
1948                             __func__, id);
1949                 }
1950                 packet_check_eom();
1951         }
1952         if (reply && c != NULL) {
1953                 packet_start(success ?
1954                     SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1955                 packet_put_int(c->remote_id);
1956                 packet_send();
1957         }
1958         xfree(rtype);
1959 }
1960 static void
1961 client_input_global_request(int type, u_int32_t seq, void *ctxt)
1962 {
1963         char *rtype;
1964         int want_reply;
1965         int success = 0;
1966
1967         rtype = packet_get_string(NULL);
1968         want_reply = packet_get_char();
1969         debug("client_input_global_request: rtype %s want_reply %d",
1970             rtype, want_reply);
1971         if (want_reply) {
1972                 packet_start(success ?
1973                     SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1974                 packet_send();
1975                 packet_write_wait();
1976         }
1977         xfree(rtype);
1978 }
1979
1980 void
1981 client_session2_setup(int id, int want_tty, int want_subsystem,
1982     const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
1983 {
1984         int len;
1985         Channel *c = NULL;
1986
1987         debug2("%s: id %d", __func__, id);
1988
1989         if ((c = channel_lookup(id)) == NULL)
1990                 fatal("client_session2_setup: channel %d: unknown channel", id);
1991
1992         packet_set_interactive(want_tty,
1993             options.ip_qos_interactive, options.ip_qos_bulk);
1994
1995         if (want_tty) {
1996                 struct winsize ws;
1997
1998                 /* Store window size in the packet. */
1999                 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
2000                         memset(&ws, 0, sizeof(ws));
2001
2002                 channel_request_start(id, "pty-req", 1);
2003                 client_expect_confirm(id, "PTY allocation", 1);
2004                 packet_put_cstring(term != NULL ? term : "");
2005                 packet_put_int((u_int)ws.ws_col);
2006                 packet_put_int((u_int)ws.ws_row);
2007                 packet_put_int((u_int)ws.ws_xpixel);
2008                 packet_put_int((u_int)ws.ws_ypixel);
2009                 if (tiop == NULL)
2010                         tiop = get_saved_tio();
2011                 tty_make_modes(-1, tiop);
2012                 packet_send();
2013                 /* XXX wait for reply */
2014                 c->client_tty = 1;
2015         }
2016
2017         /* Transfer any environment variables from client to server */
2018         if (options.num_send_env != 0 && env != NULL) {
2019                 int i, j, matched;
2020                 char *name, *val;
2021
2022                 debug("Sending environment.");
2023                 for (i = 0; env[i] != NULL; i++) {
2024                         /* Split */
2025                         name = xstrdup(env[i]);
2026                         if ((val = strchr(name, '=')) == NULL) {
2027                                 xfree(name);
2028                                 continue;
2029                         }
2030                         *val++ = '\0';
2031
2032                         matched = 0;
2033                         for (j = 0; j < options.num_send_env; j++) {
2034                                 if (match_pattern(name, options.send_env[j])) {
2035                                         matched = 1;
2036                                         break;
2037                                 }
2038                         }
2039                         if (!matched) {
2040                                 debug3("Ignored env %s", name);
2041                                 xfree(name);
2042                                 continue;
2043                         }
2044
2045                         debug("Sending env %s = %s", name, val);
2046                         channel_request_start(id, "env", 0);
2047                         packet_put_cstring(name);
2048                         packet_put_cstring(val);
2049                         packet_send();
2050                         xfree(name);
2051                 }
2052         }
2053
2054         len = buffer_len(cmd);
2055         if (len > 0) {
2056                 if (len > 900)
2057                         len = 900;
2058                 if (want_subsystem) {
2059                         debug("Sending subsystem: %.*s",
2060                             len, (u_char*)buffer_ptr(cmd));
2061                         channel_request_start(id, "subsystem", 1);
2062                         client_expect_confirm(id, "subsystem", 1);
2063                 } else {
2064                         debug("Sending command: %.*s",
2065                             len, (u_char*)buffer_ptr(cmd));
2066                         channel_request_start(id, "exec", 1);
2067                         client_expect_confirm(id, "exec", 1);
2068                 }
2069                 packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
2070                 packet_send();
2071         } else {
2072                 channel_request_start(id, "shell", 1);
2073                 client_expect_confirm(id, "shell", 1);
2074                 packet_send();
2075         }
2076 }
2077
2078 static void
2079 client_init_dispatch_20(void)
2080 {
2081         dispatch_init(&dispatch_protocol_error);
2082
2083         dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
2084         dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
2085         dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
2086         dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
2087         dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
2088         dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2089         dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2090         dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
2091         dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
2092         dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
2093         dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
2094         dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
2095
2096         /* rekeying */
2097         dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
2098
2099         /* global request reply messages */
2100         dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
2101         dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
2102 }
2103
2104 static void
2105 client_init_dispatch_13(void)
2106 {
2107         dispatch_init(NULL);
2108         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
2109         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
2110         dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
2111         dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2112         dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2113         dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2114         dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2115         dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2116         dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
2117
2118         dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
2119             &client_input_agent_open : &deny_input_open);
2120         dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2121             &x11_input_open : &deny_input_open);
2122 }
2123
2124 static void
2125 client_init_dispatch_15(void)
2126 {
2127         client_init_dispatch_13();
2128         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2129         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2130 }
2131
2132 static void
2133 client_init_dispatch(void)
2134 {
2135         if (compat20)
2136                 client_init_dispatch_20();
2137         else if (compat13)
2138                 client_init_dispatch_13();
2139         else
2140                 client_init_dispatch_15();
2141 }
2142
2143 /* client specific fatal cleanup */
2144 void
2145 cleanup_exit(int i)
2146 {
2147         leave_raw_mode(force_tty_flag);
2148         leave_non_blocking();
2149         if (options.control_path != NULL && muxserver_sock != -1)
2150                 unlink(options.control_path);
2151         ssh_kill_proxy_command();
2152         _exit(i);
2153 }