crypto/openssh/clientloop.c

   1 /* $OpenBSD: clientloop.c,v 1.236 2011/06/22 22:08:42 djm Exp $ */
   2 /*
   3  * Author: Tatu Ylonen <ylo@cs.hut.fi>
   4  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
   5  *                    All rights reserved
   6  * The main loop for the interactive session (client side).
   7  *
   8  * As far as I am concerned, the code I have written for this software
   9  * can be used freely for any purpose.  Any derived versions of this
  10  * software must be clearly marked as such, and if the derived work is
  11  * incompatible with the protocol description in the RFC file, it must be
  12  * called by a name other than "ssh" or "Secure Shell".
  13  *
  14  *
  15  * Copyright (c) 1999 Theo de Raadt.  All rights reserved.
  16  *
  17  * Redistribution and use in source and binary forms, with or without
  18  * modification, are permitted provided that the following conditions
  19  * are met:
  20  * 1. Redistributions of source code must retain the above copyright
  21  *    notice, this list of conditions and the following disclaimer.
  22  * 2. Redistributions in binary form must reproduce the above copyright
  23  *    notice, this list of conditions and the following disclaimer in the
  24  *    documentation and/or other materials provided with the distribution.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  27  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  28  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  29  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  30  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  31  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  35  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  *
  37  *
  38  * SSH2 support added by Markus Friedl.
  39  * Copyright (c) 1999, 2000, 2001 Markus Friedl.  All rights reserved.
  40  *
  41  * Redistribution and use in source and binary forms, with or without
  42  * modification, are permitted provided that the following conditions
  43  * are met:
  44  * 1. Redistributions of source code must retain the above copyright
  45  *    notice, this list of conditions and the following disclaimer.
  46  * 2. Redistributions in binary form must reproduce the above copyright
  47  *    notice, this list of conditions and the following disclaimer in the
  48  *    documentation and/or other materials provided with the distribution.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  51  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  52  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  53  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  54  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  55  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  56  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  57  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  58  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  59  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  60  */
  61
  62 #include "includes.h"
  63
  64 #include <sys/types.h>
  65 #include <sys/ioctl.h>
  66 #include <sys/param.h>
  67 #ifdef HAVE_SYS_STAT_H
  68 # include <sys/stat.h>
  69 #endif
  70 #ifdef HAVE_SYS_TIME_H
  71 # include <sys/time.h>
  72 #endif
  73 #include <sys/socket.h>
  74
  75 #include <ctype.h>
  76 #include <errno.h>
  77 #ifdef HAVE_PATHS_H
  78 #include <paths.h>
  79 #endif
  80 #include <signal.h>
  81 #include <stdarg.h>
  82 #include <stdio.h>
  83 #include <stdlib.h>
  84 #include <string.h>
  85 #include <termios.h>
  86 #include <pwd.h>
  87 #include <unistd.h>
  88
  89 #include "openbsd-compat/sys-queue.h"
  90 #include "xmalloc.h"
  91 #include "ssh.h"
  92 #include "ssh1.h"
  93 #include "ssh2.h"
  94 #include "packet.h"
  95 #include "buffer.h"
  96 #include "compat.h"
  97 #include "channels.h"
  98 #include "dispatch.h"
  99 #include "key.h"
 100 #include "cipher.h"
 101 #include "kex.h"
 102 #include "log.h"
 103 #include "readconf.h"
 104 #include "clientloop.h"
 105 #include "sshconnect.h"
 106 #include "authfd.h"
 107 #include "atomicio.h"
 108 #include "sshpty.h"
 109 #include "misc.h"
 110 #include "match.h"
 111 #include "msg.h"
 112 #include "roaming.h"
 113
 114 /* import options */
 115 extern Options options;
 116
 117 /* Flag indicating that stdin should be redirected from /dev/null. */
 118 extern int stdin_null_flag;
 119
 120 /* Flag indicating that no shell has been requested */
 121 extern int no_shell_flag;
 122
 123 /* Control socket */
 124 extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */
 125
 126 /*
 127  * Name of the host we are connecting to.  This is the name given on the
 128  * command line, or the HostName specified for the user-supplied name in a
 129  * configuration file.
 130  */
 131 extern char *host;
 132
 133 /*
 134  * Flag to indicate that we have received a window change signal which has
 135  * not yet been processed.  This will cause a message indicating the new
 136  * window size to be sent to the server a little later.  This is volatile
 137  * because this is updated in a signal handler.
 138  */
 139 static volatile sig_atomic_t received_window_change_signal = 0;
 140 static volatile sig_atomic_t received_signal = 0;
 141
 142 /* Flag indicating whether the user's terminal is in non-blocking mode. */
 143 static int in_non_blocking_mode = 0;
 144
 145 /* Time when backgrounded control master using ControlPersist should exit */
 146 static time_t control_persist_exit_time = 0;
 147
 148 /* Common data for the client loop code. */
 149 volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
 150 static int escape_char1;        /* Escape character. (proto1 only) */
 151 static int escape_pending1;     /* Last character was an escape (proto1 only) */
 152 static int last_was_cr;         /* Last character was a newline. */
 153 static int exit_status;         /* Used to store the command exit status. */
 154 static int stdin_eof;           /* EOF has been encountered on stderr. */
 155 static Buffer stdin_buffer;     /* Buffer for stdin data. */
 156 static Buffer stdout_buffer;    /* Buffer for stdout data. */
 157 static Buffer stderr_buffer;    /* Buffer for stderr data. */
 158 static u_int buffer_high;       /* Soft max buffer size. */
 159 static int connection_in;       /* Connection to server (input). */
 160 static int connection_out;      /* Connection to server (output). */
 161 static int need_rekeying;       /* Set to non-zero if rekeying is requested. */
 162 static int session_closed;      /* In SSH2: login session closed. */
 163 static int x11_refuse_time;     /* If >0, refuse x11 opens after this time. */
 164
 165 static void client_init_dispatch(void);
 166 int     session_ident = -1;
 167
 168 int     session_resumed = 0;
 169
 170 /* Track escape per proto2 channel */
 171 struct escape_filter_ctx {
 172         int escape_pending;
 173         int escape_char;
 174 };
 175
 176 /* Context for channel confirmation replies */
 177 struct channel_reply_ctx {
 178         const char *request_type;
 179         int id;
 180         enum confirm_action action;
 181 };
 182
 183 /* Global request success/failure callbacks */
 184 struct global_confirm {
 185         TAILQ_ENTRY(global_confirm) entry;
 186         global_confirm_cb *cb;
 187         void *ctx;
 188         int ref_count;
 189 };
 190 TAILQ_HEAD(global_confirms, global_confirm);
 191 static struct global_confirms global_confirms =
 192     TAILQ_HEAD_INITIALIZER(global_confirms);
 193
 194 /*XXX*/
 195 extern Kex *xxx_kex;
 196
 197 void ssh_process_session2_setup(int, int, int, Buffer *);
 198
 199 /* Restores stdin to blocking mode. */
 200
 201 static void
 202 leave_non_blocking(void)
 203 {
 204         if (in_non_blocking_mode) {
 205                 unset_nonblock(fileno(stdin));
 206                 in_non_blocking_mode = 0;
 207         }
 208 }
 209
 210 /* Puts stdin terminal in non-blocking mode. */
 211
 212 static void
 213 enter_non_blocking(void)
 214 {
 215         in_non_blocking_mode = 1;
 216         set_nonblock(fileno(stdin));
 217 }
 218
 219 /*
 220  * Signal handler for the window change signal (SIGWINCH).  This just sets a
 221  * flag indicating that the window has changed.
 222  */
 223 /*ARGSUSED */
 224 static void
 225 window_change_handler(int sig)
 226 {
 227         received_window_change_signal = 1;
 228         signal(SIGWINCH, window_change_handler);
 229 }
 230
 231 /*
 232  * Signal handler for signals that cause the program to terminate.  These
 233  * signals must be trapped to restore terminal modes.
 234  */
 235 /*ARGSUSED */
 236 static void
 237 signal_handler(int sig)
 238 {
 239         received_signal = sig;
 240         quit_pending = 1;
 241 }
 242
 243 /*
 244  * Returns current time in seconds from Jan 1, 1970 with the maximum
 245  * available resolution.
 246  */
 247
 248 static double
 249 get_current_time(void)
 250 {
 251         struct timeval tv;
 252         gettimeofday(&tv, NULL);
 253         return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
 254 }
 255
 256 /*
 257  * Sets control_persist_exit_time to the absolute time when the
 258  * backgrounded control master should exit due to expiry of the
 259  * ControlPersist timeout.  Sets it to 0 if we are not a backgrounded
 260  * control master process, or if there is no ControlPersist timeout.
 261  */
 262 static void
 263 set_control_persist_exit_time(void)
 264 {
 265         if (muxserver_sock == -1 || !options.control_persist
 266             || options.control_persist_timeout == 0) {
 267                 /* not using a ControlPersist timeout */
 268                 control_persist_exit_time = 0;
 269         } else if (channel_still_open()) {
 270                 /* some client connections are still open */
 271                 if (control_persist_exit_time > 0)
 272                         debug2("%s: cancel scheduled exit", __func__);
 273                 control_persist_exit_time = 0;
 274         } else if (control_persist_exit_time <= 0) {
 275                 /* a client connection has recently closed */
 276                 control_persist_exit_time = time(NULL) +
 277                         (time_t)options.control_persist_timeout;
 278                 debug2("%s: schedule exit in %d seconds", __func__,
 279                     options.control_persist_timeout);
 280         }
 281         /* else we are already counting down to the timeout */
 282 }
 283
 284 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
 285 void
 286 client_x11_get_proto(const char *display, const char *xauth_path,
 287     u_int trusted, u_int timeout, char **_proto, char **_data)
 288 {
 289         char cmd[1024];
 290         char line[512];
 291         char xdisplay[512];
 292         static char proto[512], data[512];
 293         FILE *f;
 294         int got_data = 0, generated = 0, do_unlink = 0, i;
 295         char *xauthdir, *xauthfile;
 296         struct stat st;
 297         u_int now;
 298
 299         xauthdir = xauthfile = NULL;
 300         *_proto = proto;
 301         *_data = data;
 302         proto[0] = data[0] = '\0';
 303
 304         if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
 305                 debug("No xauth program.");
 306         } else {
 307                 if (display == NULL) {
 308                         debug("x11_get_proto: DISPLAY not set");
 309                         return;
 310                 }
 311                 /*
 312                  * Handle FamilyLocal case where $DISPLAY does
 313                  * not match an authorization entry.  For this we
 314                  * just try "xauth list unix:displaynum.screennum".
 315                  * XXX: "localhost" match to determine FamilyLocal
 316                  *      is not perfect.
 317                  */
 318                 if (strncmp(display, "localhost:", 10) == 0) {
 319                         snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
 320                             display + 10);
 321                         display = xdisplay;
 322                 }
 323                 if (trusted == 0) {
 324                         xauthdir = xmalloc(MAXPATHLEN);
 325                         xauthfile = xmalloc(MAXPATHLEN);
 326                         mktemp_proto(xauthdir, MAXPATHLEN);
 327                         if (mkdtemp(xauthdir) != NULL) {
 328                                 do_unlink = 1;
 329                                 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
 330                                     xauthdir);
 331                                 snprintf(cmd, sizeof(cmd),
 332                                     "%s -f %s generate %s " SSH_X11_PROTO
 333                                     " untrusted timeout %u 2>" _PATH_DEVNULL,
 334                                     xauth_path, xauthfile, display, timeout);
 335                                 debug2("x11_get_proto: %s", cmd);
 336                                 if (system(cmd) == 0)
 337                                         generated = 1;
 338                                 if (x11_refuse_time == 0) {
 339                                         now = time(NULL) + 1;
 340                                         if (UINT_MAX - timeout < now)
 341                                                 x11_refuse_time = UINT_MAX;
 342                                         else
 343                                                 x11_refuse_time = now + timeout;
 344                                 }
 345                         }
 346                 }
 347
 348                 /*
 349                  * When in untrusted mode, we read the cookie only if it was
 350                  * successfully generated as an untrusted one in the step
 351                  * above.
 352                  */
 353                 if (trusted || generated) {
 354                         snprintf(cmd, sizeof(cmd),
 355                             "%s %s%s list %s 2>" _PATH_DEVNULL,
 356                             xauth_path,
 357                             generated ? "-f " : "" ,
 358                             generated ? xauthfile : "",
 359                             display);
 360                         debug2("x11_get_proto: %s", cmd);
 361                         f = popen(cmd, "r");
 362                         if (f && fgets(line, sizeof(line), f) &&
 363                             sscanf(line, "%*s %511s %511s", proto, data) == 2)
 364                                 got_data = 1;
 365                         if (f)
 366                                 pclose(f);
 367                 } else
 368                         error("Warning: untrusted X11 forwarding setup failed: "
 369                             "xauth key data not generated");
 370         }
 371
 372         if (do_unlink) {
 373                 unlink(xauthfile);
 374                 rmdir(xauthdir);
 375         }
 376         if (xauthdir)
 377                 xfree(xauthdir);
 378         if (xauthfile)
 379                 xfree(xauthfile);
 380
 381         /*
 382          * If we didn't get authentication data, just make up some
 383          * data.  The forwarding code will check the validity of the
 384          * response anyway, and substitute this data.  The X11
 385          * server, however, will ignore this fake data and use
 386          * whatever authentication mechanisms it was using otherwise
 387          * for the local connection.
 388          */
 389         if (!got_data) {
 390                 u_int32_t rnd = 0;
 391
 392                 logit("Warning: No xauth data; "
 393                     "using fake authentication data for X11 forwarding.");
 394                 strlcpy(proto, SSH_X11_PROTO, sizeof proto);
 395                 for (i = 0; i < 16; i++) {
 396                         if (i % 4 == 0)
 397                                 rnd = arc4random();
 398                         snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
 399                             rnd & 0xff);
 400                         rnd >>= 8;
 401                 }
 402         }
 403 }
 404
 405 /*
 406  * This is called when the interactive is entered.  This checks if there is
 407  * an EOF coming on stdin.  We must check this explicitly, as select() does
 408  * not appear to wake up when redirecting from /dev/null.
 409  */
 410
 411 static void
 412 client_check_initial_eof_on_stdin(void)
 413 {
 414         int len;
 415         char buf[1];
 416
 417         /*
 418          * If standard input is to be "redirected from /dev/null", we simply
 419          * mark that we have seen an EOF and send an EOF message to the
 420          * server. Otherwise, we try to read a single character; it appears
 421          * that for some files, such /dev/null, select() never wakes up for
 422          * read for this descriptor, which means that we never get EOF.  This
 423          * way we will get the EOF if stdin comes from /dev/null or similar.
 424          */
 425         if (stdin_null_flag) {
 426                 /* Fake EOF on stdin. */
 427                 debug("Sending eof.");
 428                 stdin_eof = 1;
 429                 packet_start(SSH_CMSG_EOF);
 430                 packet_send();
 431         } else {
 432                 enter_non_blocking();
 433
 434                 /* Check for immediate EOF on stdin. */
 435                 len = read(fileno(stdin), buf, 1);
 436                 if (len == 0) {
 437                         /*
 438                          * EOF.  Record that we have seen it and send
 439                          * EOF to server.
 440                          */
 441                         debug("Sending eof.");
 442                         stdin_eof = 1;
 443                         packet_start(SSH_CMSG_EOF);
 444                         packet_send();
 445                 } else if (len > 0) {
 446                         /*
 447                          * Got data.  We must store the data in the buffer,
 448                          * and also process it as an escape character if
 449                          * appropriate.
 450                          */
 451                         if ((u_char) buf[0] == escape_char1)
 452                                 escape_pending1 = 1;
 453                         else
 454                                 buffer_append(&stdin_buffer, buf, 1);
 455                 }
 456                 leave_non_blocking();
 457         }
 458 }
 459
 460
 461 /*
 462  * Make packets from buffered stdin data, and buffer them for sending to the
 463  * connection.
 464  */
 465
 466 static void
 467 client_make_packets_from_stdin_data(void)
 468 {
 469         u_int len;
 470
 471         /* Send buffered stdin data to the server. */
 472         while (buffer_len(&stdin_buffer) > 0 &&
 473             packet_not_very_much_data_to_write()) {
 474                 len = buffer_len(&stdin_buffer);
 475                 /* Keep the packets at reasonable size. */
 476                 if (len > packet_get_maxsize())
 477                         len = packet_get_maxsize();
 478                 packet_start(SSH_CMSG_STDIN_DATA);
 479                 packet_put_string(buffer_ptr(&stdin_buffer), len);
 480                 packet_send();
 481                 buffer_consume(&stdin_buffer, len);
 482                 /* If we have a pending EOF, send it now. */
 483                 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
 484                         packet_start(SSH_CMSG_EOF);
 485                         packet_send();
 486                 }
 487         }
 488 }
 489
 490 /*
 491  * Checks if the client window has changed, and sends a packet about it to
 492  * the server if so.  The actual change is detected elsewhere (by a software
 493  * interrupt on Unix); this just checks the flag and sends a message if
 494  * appropriate.
 495  */
 496
 497 static void
 498 client_check_window_change(void)
 499 {
 500         struct winsize ws;
 501
 502         if (! received_window_change_signal)
 503                 return;
 504         /** XXX race */
 505         received_window_change_signal = 0;
 506
 507         debug2("client_check_window_change: changed");
 508
 509         if (compat20) {
 510                 channel_send_window_changes();
 511         } else {
 512                 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
 513                         return;
 514                 packet_start(SSH_CMSG_WINDOW_SIZE);
 515                 packet_put_int((u_int)ws.ws_row);
 516                 packet_put_int((u_int)ws.ws_col);
 517                 packet_put_int((u_int)ws.ws_xpixel);
 518                 packet_put_int((u_int)ws.ws_ypixel);
 519                 packet_send();
 520         }
 521 }
 522
 523 static void
 524 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
 525 {
 526         struct global_confirm *gc;
 527
 528         if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
 529                 return;
 530         if (gc->cb != NULL)
 531                 gc->cb(type, seq, gc->ctx);
 532         if (--gc->ref_count <= 0) {
 533                 TAILQ_REMOVE(&global_confirms, gc, entry);
 534                 bzero(gc, sizeof(*gc));
 535                 xfree(gc);
 536         }
 537
 538         packet_set_alive_timeouts(0);
 539 }
 540
 541 static void
 542 server_alive_check(void)
 543 {
 544         if (packet_inc_alive_timeouts() > options.server_alive_count_max) {
 545                 logit("Timeout, server %s not responding.", host);
 546                 cleanup_exit(255);
 547         }
 548         packet_start(SSH2_MSG_GLOBAL_REQUEST);
 549         packet_put_cstring("keepalive@openssh.com");
 550         packet_put_char(1);     /* boolean: want reply */
 551         packet_send();
 552         /* Insert an empty placeholder to maintain ordering */
 553         client_register_global_confirm(NULL, NULL);
 554 }
 555
 556 /*
 557  * Waits until the client can do something (some data becomes available on
 558  * one of the file descriptors).
 559  */
 560 static void
 561 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
 562     int *maxfdp, u_int *nallocp, int rekeying)
 563 {
 564         struct timeval tv, *tvp;
 565         int timeout_secs;
 566         int ret;
 567
 568         /* Add any selections by the channel mechanism. */
 569         channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
 570
 571         if (!compat20) {
 572                 /* Read from the connection, unless our buffers are full. */
 573                 if (buffer_len(&stdout_buffer) < buffer_high &&
 574                     buffer_len(&stderr_buffer) < buffer_high &&
 575                     channel_not_very_much_buffered_data())
 576                         FD_SET(connection_in, *readsetp);
 577                 /*
 578                  * Read from stdin, unless we have seen EOF or have very much
 579                  * buffered data to send to the server.
 580                  */
 581                 if (!stdin_eof && packet_not_very_much_data_to_write())
 582                         FD_SET(fileno(stdin), *readsetp);
 583
 584                 /* Select stdout/stderr if have data in buffer. */
 585                 if (buffer_len(&stdout_buffer) > 0)
 586                         FD_SET(fileno(stdout), *writesetp);
 587                 if (buffer_len(&stderr_buffer) > 0)
 588                         FD_SET(fileno(stderr), *writesetp);
 589         } else {
 590                 /* channel_prepare_select could have closed the last channel */
 591                 if (session_closed && !channel_still_open() &&
 592                     !packet_have_data_to_write()) {
 593                         /* clear mask since we did not call select() */
 594                         memset(*readsetp, 0, *nallocp);
 595                         memset(*writesetp, 0, *nallocp);
 596                         return;
 597                 } else {
 598                         FD_SET(connection_in, *readsetp);
 599                 }
 600         }
 601
 602         /* Select server connection if have data to write to the server. */
 603         if (packet_have_data_to_write())
 604                 FD_SET(connection_out, *writesetp);
 605
 606         /*
 607          * Wait for something to happen.  This will suspend the process until
 608          * some selected descriptor can be read, written, or has some other
 609          * event pending, or a timeout expires.
 610          */
 611
 612         timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */
 613         if (options.server_alive_interval > 0 && compat20)
 614                 timeout_secs = options.server_alive_interval;
 615         set_control_persist_exit_time();
 616         if (control_persist_exit_time > 0) {
 617                 timeout_secs = MIN(timeout_secs,
 618                         control_persist_exit_time - time(NULL));
 619                 if (timeout_secs < 0)
 620                         timeout_secs = 0;
 621         }
 622         if (timeout_secs == INT_MAX)
 623                 tvp = NULL;
 624         else {
 625                 tv.tv_sec = timeout_secs;
 626                 tv.tv_usec = 0;
 627                 tvp = &tv;
 628         }
 629
 630         ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
 631         if (ret < 0) {
 632                 char buf[100];
 633
 634                 /*
 635                  * We have to clear the select masks, because we return.
 636                  * We have to return, because the mainloop checks for the flags
 637                  * set by the signal handlers.
 638                  */
 639                 memset(*readsetp, 0, *nallocp);
 640                 memset(*writesetp, 0, *nallocp);
 641
 642                 if (errno == EINTR)
 643                         return;
 644                 /* Note: we might still have data in the buffers. */
 645                 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
 646                 buffer_append(&stderr_buffer, buf, strlen(buf));
 647                 quit_pending = 1;
 648         } else if (ret == 0)
 649                 server_alive_check();
 650 }
 651
 652 static void
 653 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
 654 {
 655         /* Flush stdout and stderr buffers. */
 656         if (buffer_len(bout) > 0)
 657                 atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
 658                     buffer_len(bout));
 659         if (buffer_len(berr) > 0)
 660                 atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
 661                     buffer_len(berr));
 662
 663         leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
 664
 665         /*
 666          * Free (and clear) the buffer to reduce the amount of data that gets
 667          * written to swap.
 668          */
 669         buffer_free(bin);
 670         buffer_free(bout);
 671         buffer_free(berr);
 672
 673         /* Send the suspend signal to the program itself. */
 674         kill(getpid(), SIGTSTP);
 675
 676         /* Reset window sizes in case they have changed */
 677         received_window_change_signal = 1;
 678
 679         /* OK, we have been continued by the user. Reinitialize buffers. */
 680         buffer_init(bin);
 681         buffer_init(bout);
 682         buffer_init(berr);
 683
 684         enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
 685 }
 686
 687 static void
 688 client_process_net_input(fd_set *readset)
 689 {
 690         int len, cont = 0;
 691         char buf[SSH_IOBUFSZ];
 692
 693         /*
 694          * Read input from the server, and add any such data to the buffer of
 695          * the packet subsystem.
 696          */
 697         if (FD_ISSET(connection_in, readset)) {
 698                 /* Read as much as possible. */
 699                 len = roaming_read(connection_in, buf, sizeof(buf), &cont);
 700                 if (len == 0 && cont == 0) {
 701                         /*
 702                          * Received EOF.  The remote host has closed the
 703                          * connection.
 704                          */
 705                         snprintf(buf, sizeof buf,
 706                             "Connection to %.300s closed by remote host.\r\n",
 707                             host);
 708                         buffer_append(&stderr_buffer, buf, strlen(buf));
 709                         quit_pending = 1;
 710                         return;
 711                 }
 712                 /*
 713                  * There is a kernel bug on Solaris that causes select to
 714                  * sometimes wake up even though there is no data available.
 715                  */
 716                 if (len < 0 &&
 717                     (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
 718                         len = 0;
 719
 720                 if (len < 0) {
 721                         /*
 722                          * An error has encountered.  Perhaps there is a
 723                          * network problem.
 724                          */
 725                         snprintf(buf, sizeof buf,
 726                             "Read from remote host %.300s: %.100s\r\n",
 727                             host, strerror(errno));
 728                         buffer_append(&stderr_buffer, buf, strlen(buf));
 729                         quit_pending = 1;
 730                         return;
 731                 }
 732                 packet_process_incoming(buf, len);
 733         }
 734 }
 735
 736 static void
 737 client_status_confirm(int type, Channel *c, void *ctx)
 738 {
 739         struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
 740         char errmsg[256];
 741         int tochan;
 742
 743         /*
 744          * If a TTY was explicitly requested, then a failure to allocate
 745          * one is fatal.
 746          */
 747         if (cr->action == CONFIRM_TTY &&
 748             (options.request_tty == REQUEST_TTY_FORCE ||
 749             options.request_tty == REQUEST_TTY_YES))
 750                 cr->action = CONFIRM_CLOSE;
 751
 752         /* XXX supress on mux _client_ quietmode */
 753         tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
 754             c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
 755
 756         if (type == SSH2_MSG_CHANNEL_SUCCESS) {
 757                 debug2("%s request accepted on channel %d",
 758                     cr->request_type, c->self);
 759         } else if (type == SSH2_MSG_CHANNEL_FAILURE) {
 760                 if (tochan) {
 761                         snprintf(errmsg, sizeof(errmsg),
 762                             "%s request failed\r\n", cr->request_type);
 763                 } else {
 764                         snprintf(errmsg, sizeof(errmsg),
 765                             "%s request failed on channel %d",
 766                             cr->request_type, c->self);
 767                 }
 768                 /* If error occurred on primary session channel, then exit */
 769                 if (cr->action == CONFIRM_CLOSE && c->self == session_ident)
 770                         fatal("%s", errmsg);
 771                 /*
 772                  * If error occurred on mux client, append to
 773                  * their stderr.
 774                  */
 775                 if (tochan) {
 776                         buffer_append(&c->extended, errmsg,
 777                             strlen(errmsg));
 778                 } else
 779                         error("%s", errmsg);
 780                 if (cr->action == CONFIRM_TTY) {
 781                         /*
 782                          * If a TTY allocation error occurred, then arrange
 783                          * for the correct TTY to leave raw mode.
 784                          */
 785                         if (c->self == session_ident)
 786                                 leave_raw_mode(0);
 787                         else
 788                                 mux_tty_alloc_failed(c);
 789                 } else if (cr->action == CONFIRM_CLOSE) {
 790                         chan_read_failed(c);
 791                         chan_write_failed(c);
 792                 }
 793         }
 794         xfree(cr);
 795 }
 796
 797 static void
 798 client_abandon_status_confirm(Channel *c, void *ctx)
 799 {
 800         xfree(ctx);
 801 }
 802
 803 void
 804 client_expect_confirm(int id, const char *request,
 805     enum confirm_action action)
 806 {
 807         struct channel_reply_ctx *cr = xmalloc(sizeof(*cr));
 808
 809         cr->request_type = request;
 810         cr->action = action;
 811
 812         channel_register_status_confirm(id, client_status_confirm,
 813             client_abandon_status_confirm, cr);
 814 }
 815
 816 void
 817 client_register_global_confirm(global_confirm_cb *cb, void *ctx)
 818 {
 819         struct global_confirm *gc, *last_gc;
 820
 821         /* Coalesce identical callbacks */
 822         last_gc = TAILQ_LAST(&global_confirms, global_confirms);
 823         if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
 824                 if (++last_gc->ref_count >= INT_MAX)
 825                         fatal("%s: last_gc->ref_count = %d",
 826                             __func__, last_gc->ref_count);
 827                 return;
 828         }
 829
 830         gc = xmalloc(sizeof(*gc));
 831         gc->cb = cb;
 832         gc->ctx = ctx;
 833         gc->ref_count = 1;
 834         TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
 835 }
 836
 837 static void
 838 process_cmdline(void)
 839 {
 840         void (*handler)(int);
 841         char *s, *cmd, *cancel_host;
 842         int delete = 0;
 843         int local = 0, remote = 0, dynamic = 0;
 844         int cancel_port;
 845         Forward fwd;
 846
 847         bzero(&fwd, sizeof(fwd));
 848         fwd.listen_host = fwd.connect_host = NULL;
 849
 850         leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
 851         handler = signal(SIGINT, SIG_IGN);
 852         cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
 853         if (s == NULL)
 854                 goto out;
 855         while (isspace(*s))
 856                 s++;
 857         if (*s == '-')
 858                 s++;    /* Skip cmdline '-', if any */
 859         if (*s == '\0')
 860                 goto out;
 861
 862         if (*s == 'h' || *s == 'H' || *s == '?') {
 863                 logit("Commands:");
 864                 logit("      -L[bind_address:]port:host:hostport    "
 865                     "Request local forward");
 866                 logit("      -R[bind_address:]port:host:hostport    "
 867                     "Request remote forward");
 868                 logit("      -D[bind_address:]port                  "
 869                     "Request dynamic forward");
 870                 logit("      -KR[bind_address:]port                 "
 871                     "Cancel remote forward");
 872                 if (!options.permit_local_command)
 873                         goto out;
 874                 logit("      !args                                  "
 875                     "Execute local command");
 876                 goto out;
 877         }
 878
 879         if (*s == '!' && options.permit_local_command) {
 880                 s++;
 881                 ssh_local_cmd(s);
 882                 goto out;
 883         }
 884
 885         if (*s == 'K') {
 886                 delete = 1;
 887                 s++;
 888         }
 889         if (*s == 'L')
 890                 local = 1;
 891         else if (*s == 'R')
 892                 remote = 1;
 893         else if (*s == 'D')
 894                 dynamic = 1;
 895         else {
 896                 logit("Invalid command.");
 897                 goto out;
 898         }
 899
 900         if ((local || dynamic) && delete) {
 901                 logit("Not supported.");
 902                 goto out;
 903         }
 904         if (remote && delete && !compat20) {
 905                 logit("Not supported for SSH protocol version 1.");
 906                 goto out;
 907         }
 908
 909         while (isspace(*++s))
 910                 ;
 911
 912         /* XXX update list of forwards in options */
 913         if (delete) {
 914                 cancel_port = 0;
 915                 cancel_host = hpdelim(&s);      /* may be NULL */
 916                 if (s != NULL) {
 917                         cancel_port = a2port(s);
 918                         cancel_host = cleanhostname(cancel_host);
 919                 } else {
 920                         cancel_port = a2port(cancel_host);
 921                         cancel_host = NULL;
 922                 }
 923                 if (cancel_port <= 0) {
 924                         logit("Bad forwarding close port");
 925                         goto out;
 926                 }
 927                 channel_request_rforward_cancel(cancel_host, cancel_port);
 928         } else {
 929                 if (!parse_forward(&fwd, s, dynamic, remote)) {
 930                         logit("Bad forwarding specification.");
 931                         goto out;
 932                 }
 933                 if (local || dynamic) {
 934                         if (channel_setup_local_fwd_listener(fwd.listen_host,
 935                             fwd.listen_port, fwd.connect_host,
 936                             fwd.connect_port, options.gateway_ports) < 0) {
 937                                 logit("Port forwarding failed.");
 938                                 goto out;
 939                         }
 940                 } else {
 941                         if (channel_request_remote_forwarding(fwd.listen_host,
 942                             fwd.listen_port, fwd.connect_host,
 943                             fwd.connect_port) < 0) {
 944                                 logit("Port forwarding failed.");
 945                                 goto out;
 946                         }
 947                 }
 948
 949                 logit("Forwarding port.");
 950         }
 951
 952 out:
 953         signal(SIGINT, handler);
 954         enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
 955         if (cmd)
 956                 xfree(cmd);
 957         if (fwd.listen_host != NULL)
 958                 xfree(fwd.listen_host);
 959         if (fwd.connect_host != NULL)
 960                 xfree(fwd.connect_host);
 961 }
 962
 963 /*
 964  * Process the characters one by one, call with c==NULL for proto1 case.
 965  */
 966 static int
 967 process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
 968     char *buf, int len)
 969 {
 970         char string[1024];
 971         pid_t pid;
 972         int bytes = 0;
 973         u_int i;
 974         u_char ch;
 975         char *s;
 976         int *escape_pendingp, escape_char;
 977         struct escape_filter_ctx *efc;
 978
 979         if (c == NULL) {
 980                 escape_pendingp = &escape_pending1;
 981                 escape_char = escape_char1;
 982         } else {
 983                 if (c->filter_ctx == NULL)
 984                         return 0;
 985                 efc = (struct escape_filter_ctx *)c->filter_ctx;
 986                 escape_pendingp = &efc->escape_pending;
 987                 escape_char = efc->escape_char;
 988         }
 989
 990         if (len <= 0)
 991                 return (0);
 992
 993         for (i = 0; i < (u_int)len; i++) {
 994                 /* Get one character at a time. */
 995                 ch = buf[i];
 996
 997                 if (*escape_pendingp) {
 998                         /* We have previously seen an escape character. */
 999                         /* Clear the flag now. */
1000                         *escape_pendingp = 0;
1001
1002                         /* Process the escaped character. */
1003                         switch (ch) {
1004                         case '.':
1005                                 /* Terminate the connection. */
1006                                 snprintf(string, sizeof string, "%c.\r\n",
1007                                     escape_char);
1008                                 buffer_append(berr, string, strlen(string));
1009
1010                                 if (c && c->ctl_chan != -1) {
1011                                         chan_read_failed(c);
1012                                         chan_write_failed(c);
1013                                         return 0;
1014                                 } else
1015                                         quit_pending = 1;
1016                                 return -1;
1017
1018                         case 'Z' - 64:
1019                                 /* XXX support this for mux clients */
1020                                 if (c && c->ctl_chan != -1) {
1021  noescape:
1022                                         snprintf(string, sizeof string,
1023                                             "%c%c escape not available to "
1024                                             "multiplexed sessions\r\n",
1025                                             escape_char, ch);
1026                                         buffer_append(berr, string,
1027                                             strlen(string));
1028                                         continue;
1029                                 }
1030                                 /* Suspend the program. Inform the user */
1031                                 snprintf(string, sizeof string,
1032                                     "%c^Z [suspend ssh]\r\n", escape_char);
1033                                 buffer_append(berr, string, strlen(string));
1034
1035                                 /* Restore terminal modes and suspend. */
1036                                 client_suspend_self(bin, bout, berr);
1037
1038                                 /* We have been continued. */
1039                                 continue;
1040
1041                         case 'B':
1042                                 if (compat20) {
1043                                         snprintf(string, sizeof string,
1044                                             "%cB\r\n", escape_char);
1045                                         buffer_append(berr, string,
1046                                             strlen(string));
1047                                         channel_request_start(session_ident,
1048                                             "break", 0);
1049                                         packet_put_int(1000);
1050                                         packet_send();
1051                                 }
1052                                 continue;
1053
1054                         case 'R':
1055                                 if (compat20) {
1056                                         if (datafellows & SSH_BUG_NOREKEY)
1057                                                 logit("Server does not "
1058                                                     "support re-keying");
1059                                         else
1060                                                 need_rekeying = 1;
1061                                 }
1062                                 continue;
1063
1064                         case '&':
1065                                 if (c && c->ctl_chan != -1)
1066                                         goto noescape;
1067                                 /*
1068                                  * Detach the program (continue to serve
1069                                  * connections, but put in background and no
1070                                  * more new connections).
1071                                  */
1072                                 /* Restore tty modes. */
1073                                 leave_raw_mode(
1074                                     options.request_tty == REQUEST_TTY_FORCE);
1075
1076                                 /* Stop listening for new connections. */
1077                                 channel_stop_listening();
1078
1079                                 snprintf(string, sizeof string,
1080                                     "%c& [backgrounded]\n", escape_char);
1081                                 buffer_append(berr, string, strlen(string));
1082
1083                                 /* Fork into background. */
1084                                 pid = fork();
1085                                 if (pid < 0) {
1086                                         error("fork: %.100s", strerror(errno));
1087                                         continue;
1088                                 }
1089                                 if (pid != 0) { /* This is the parent. */
1090                                         /* The parent just exits. */
1091                                         exit(0);
1092                                 }
1093                                 /* The child continues serving connections. */
1094                                 if (compat20) {
1095                                         buffer_append(bin, "\004", 1);
1096                                         /* fake EOF on stdin */
1097                                         return -1;
1098                                 } else if (!stdin_eof) {
1099                                         /*
1100                                          * Sending SSH_CMSG_EOF alone does not
1101                                          * always appear to be enough.  So we
1102                                          * try to send an EOF character first.
1103                                          */
1104                                         packet_start(SSH_CMSG_STDIN_DATA);
1105                                         packet_put_string("\004", 1);
1106                                         packet_send();
1107                                         /* Close stdin. */
1108                                         stdin_eof = 1;
1109                                         if (buffer_len(bin) == 0) {
1110                                                 packet_start(SSH_CMSG_EOF);
1111                                                 packet_send();
1112                                         }
1113                                 }
1114                                 continue;
1115
1116                         case '?':
1117                                 if (c && c->ctl_chan != -1) {
1118                                         snprintf(string, sizeof string,
1119 "%c?\r\n\
1120 Supported escape sequences:\r\n\
1121   %c.  - terminate session\r\n\
1122   %cB  - send a BREAK to the remote system\r\n\
1123   %cR  - Request rekey (SSH protocol 2 only)\r\n\
1124   %c#  - list forwarded connections\r\n\
1125   %c?  - this message\r\n\
1126   %c%c  - send the escape character by typing it twice\r\n\
1127 (Note that escapes are only recognized immediately after newline.)\r\n",
1128                                             escape_char, escape_char,
1129                                             escape_char, escape_char,
1130                                             escape_char, escape_char,
1131                                             escape_char, escape_char);
1132                                 } else {
1133                                         snprintf(string, sizeof string,
1134 "%c?\r\n\
1135 Supported escape sequences:\r\n\
1136   %c.  - terminate connection (and any multiplexed sessions)\r\n\
1137   %cB  - send a BREAK to the remote system\r\n\
1138   %cC  - open a command line\r\n\
1139   %cR  - Request rekey (SSH protocol 2 only)\r\n\
1140   %c^Z - suspend ssh\r\n\
1141   %c#  - list forwarded connections\r\n\
1142   %c&  - background ssh (when waiting for connections to terminate)\r\n\
1143   %c?  - this message\r\n\
1144   %c%c  - send the escape character by typing it twice\r\n\
1145 (Note that escapes are only recognized immediately after newline.)\r\n",
1146                                             escape_char, escape_char,
1147                                             escape_char, escape_char,
1148                                             escape_char, escape_char,
1149                                             escape_char, escape_char,
1150                                             escape_char, escape_char,
1151                                             escape_char);
1152                                 }
1153                                 buffer_append(berr, string, strlen(string));
1154                                 continue;
1155
1156                         case '#':
1157                                 snprintf(string, sizeof string, "%c#\r\n",
1158                                     escape_char);
1159                                 buffer_append(berr, string, strlen(string));
1160                                 s = channel_open_message();
1161                                 buffer_append(berr, s, strlen(s));
1162                                 xfree(s);
1163                                 continue;
1164
1165                         case 'C':
1166                                 if (c && c->ctl_chan != -1)
1167                                         goto noescape;
1168                                 process_cmdline();
1169                                 continue;
1170
1171                         default:
1172                                 if (ch != escape_char) {
1173                                         buffer_put_char(bin, escape_char);
1174                                         bytes++;
1175                                 }
1176                                 /* Escaped characters fall through here */
1177                                 break;
1178                         }
1179                 } else {
1180                         /*
1181                          * The previous character was not an escape char.
1182                          * Check if this is an escape.
1183                          */
1184                         if (last_was_cr && ch == escape_char) {
1185                                 /*
1186                                  * It is. Set the flag and continue to
1187                                  * next character.
1188                                  */
1189                                 *escape_pendingp = 1;
1190                                 continue;
1191                         }
1192                 }
1193
1194                 /*
1195                  * Normal character.  Record whether it was a newline,
1196                  * and append it to the buffer.
1197                  */
1198                 last_was_cr = (ch == '\r' || ch == '\n');
1199                 buffer_put_char(bin, ch);
1200                 bytes++;
1201         }
1202         return bytes;
1203 }
1204
1205 static void
1206 client_process_input(fd_set *readset)
1207 {
1208         int len;
1209         char buf[SSH_IOBUFSZ];
1210
1211         /* Read input from stdin. */
1212         if (FD_ISSET(fileno(stdin), readset)) {
1213                 /* Read as much as possible. */
1214                 len = read(fileno(stdin), buf, sizeof(buf));
1215                 if (len < 0 &&
1216                     (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
1217                         return;         /* we'll try again later */
1218                 if (len <= 0) {
1219                         /*
1220                          * Received EOF or error.  They are treated
1221                          * similarly, except that an error message is printed
1222                          * if it was an error condition.
1223                          */
1224                         if (len < 0) {
1225                                 snprintf(buf, sizeof buf, "read: %.100s\r\n",
1226                                     strerror(errno));
1227                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1228                         }
1229                         /* Mark that we have seen EOF. */
1230                         stdin_eof = 1;
1231                         /*
1232                          * Send an EOF message to the server unless there is
1233                          * data in the buffer.  If there is data in the
1234                          * buffer, no message will be sent now.  Code
1235                          * elsewhere will send the EOF when the buffer
1236                          * becomes empty if stdin_eof is set.
1237                          */
1238                         if (buffer_len(&stdin_buffer) == 0) {
1239                                 packet_start(SSH_CMSG_EOF);
1240                                 packet_send();
1241                         }
1242                 } else if (escape_char1 == SSH_ESCAPECHAR_NONE) {
1243                         /*
1244                          * Normal successful read, and no escape character.
1245                          * Just append the data to buffer.
1246                          */
1247                         buffer_append(&stdin_buffer, buf, len);
1248                 } else {
1249                         /*
1250                          * Normal, successful read.  But we have an escape
1251                          * character and have to process the characters one
1252                          * by one.
1253                          */
1254                         if (process_escapes(NULL, &stdin_buffer,
1255                             &stdout_buffer, &stderr_buffer, buf, len) == -1)
1256                                 return;
1257                 }
1258         }
1259 }
1260
1261 static void
1262 client_process_output(fd_set *writeset)
1263 {
1264         int len;
1265         char buf[100];
1266
1267         /* Write buffered output to stdout. */
1268         if (FD_ISSET(fileno(stdout), writeset)) {
1269                 /* Write as much data as possible. */
1270                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1271                     buffer_len(&stdout_buffer));
1272                 if (len <= 0) {
1273                         if (errno == EINTR || errno == EAGAIN ||
1274                             errno == EWOULDBLOCK)
1275                                 len = 0;
1276                         else {
1277                                 /*
1278                                  * An error or EOF was encountered.  Put an
1279                                  * error message to stderr buffer.
1280                                  */
1281                                 snprintf(buf, sizeof buf,
1282                                     "write stdout: %.50s\r\n", strerror(errno));
1283                                 buffer_append(&stderr_buffer, buf, strlen(buf));
1284                                 quit_pending = 1;
1285                                 return;
1286                         }
1287                 }
1288                 /* Consume printed data from the buffer. */
1289                 buffer_consume(&stdout_buffer, len);
1290         }
1291         /* Write buffered output to stderr. */
1292         if (FD_ISSET(fileno(stderr), writeset)) {
1293                 /* Write as much data as possible. */
1294                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1295                     buffer_len(&stderr_buffer));
1296                 if (len <= 0) {
1297                         if (errno == EINTR || errno == EAGAIN ||
1298                             errno == EWOULDBLOCK)
1299                                 len = 0;
1300                         else {
1301                                 /*
1302                                  * EOF or error, but can't even print
1303                                  * error message.
1304                                  */
1305                                 quit_pending = 1;
1306                                 return;
1307                         }
1308                 }
1309                 /* Consume printed characters from the buffer. */
1310                 buffer_consume(&stderr_buffer, len);
1311         }
1312 }
1313
1314 /*
1315  * Get packets from the connection input buffer, and process them as long as
1316  * there are packets available.
1317  *
1318  * Any unknown packets received during the actual
1319  * session cause the session to terminate.  This is
1320  * intended to make debugging easier since no
1321  * confirmations are sent.  Any compatible protocol
1322  * extensions must be negotiated during the
1323  * preparatory phase.
1324  */
1325
1326 static void
1327 client_process_buffered_input_packets(void)
1328 {
1329         dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
1330             compat20 ? xxx_kex : NULL);
1331 }
1332
1333 /* scan buf[] for '~' before sending data to the peer */
1334
1335 /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1336 void *
1337 client_new_escape_filter_ctx(int escape_char)
1338 {
1339         struct escape_filter_ctx *ret;
1340
1341         ret = xmalloc(sizeof(*ret));
1342         ret->escape_pending = 0;
1343         ret->escape_char = escape_char;
1344         return (void *)ret;
1345 }
1346
1347 /* Free the escape filter context on channel free */
1348 void
1349 client_filter_cleanup(int cid, void *ctx)
1350 {
1351         xfree(ctx);
1352 }
1353
1354 int
1355 client_simple_escape_filter(Channel *c, char *buf, int len)
1356 {
1357         if (c->extended_usage != CHAN_EXTENDED_WRITE)
1358                 return 0;
1359
1360         return process_escapes(c, &c->input, &c->output, &c->extended,
1361             buf, len);
1362 }
1363
1364 static void
1365 client_channel_closed(int id, void *arg)
1366 {
1367         channel_cancel_cleanup(id);
1368         session_closed = 1;
1369         leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1370 }
1371
1372 /*
1373  * Implements the interactive session with the server.  This is called after
1374  * the user has been authenticated, and a command has been started on the
1375  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1376  * used as an escape character for terminating or suspending the session.
1377  */
1378
1379 int
1380 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1381 {
1382         fd_set *readset = NULL, *writeset = NULL;
1383         double start_time, total_time;
1384         int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1385         u_int64_t ibytes, obytes;
1386         u_int nalloc = 0;
1387         char buf[100];
1388
1389         debug("Entering interactive session.");
1390
1391         start_time = get_current_time();
1392
1393         /* Initialize variables. */
1394         escape_pending1 = 0;
1395         last_was_cr = 1;
1396         exit_status = -1;
1397         stdin_eof = 0;
1398         buffer_high = 64 * 1024;
1399         connection_in = packet_get_connection_in();
1400         connection_out = packet_get_connection_out();
1401         max_fd = MAX(connection_in, connection_out);
1402
1403         if (!compat20) {
1404                 /* enable nonblocking unless tty */
1405                 if (!isatty(fileno(stdin)))
1406                         set_nonblock(fileno(stdin));
1407                 if (!isatty(fileno(stdout)))
1408                         set_nonblock(fileno(stdout));
1409                 if (!isatty(fileno(stderr)))
1410                         set_nonblock(fileno(stderr));
1411                 max_fd = MAX(max_fd, fileno(stdin));
1412                 max_fd = MAX(max_fd, fileno(stdout));
1413                 max_fd = MAX(max_fd, fileno(stderr));
1414         }
1415         quit_pending = 0;
1416         escape_char1 = escape_char_arg;
1417
1418         /* Initialize buffers. */
1419         buffer_init(&stdin_buffer);
1420         buffer_init(&stdout_buffer);
1421         buffer_init(&stderr_buffer);
1422
1423         client_init_dispatch();
1424
1425         /*
1426          * Set signal handlers, (e.g. to restore non-blocking mode)
1427          * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1428          */
1429         if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1430                 signal(SIGHUP, signal_handler);
1431         if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1432                 signal(SIGINT, signal_handler);
1433         if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1434                 signal(SIGQUIT, signal_handler);
1435         if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1436                 signal(SIGTERM, signal_handler);
1437         signal(SIGWINCH, window_change_handler);
1438
1439         if (have_pty)
1440                 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1441
1442         if (compat20) {
1443                 session_ident = ssh2_chan_id;
1444                 if (session_ident != -1) {
1445                         if (escape_char_arg != SSH_ESCAPECHAR_NONE) {
1446                                 channel_register_filter(session_ident,
1447                                     client_simple_escape_filter, NULL,
1448                                     client_filter_cleanup,
1449                                     client_new_escape_filter_ctx(
1450                                     escape_char_arg));
1451                         }
1452                         channel_register_cleanup(session_ident,
1453                             client_channel_closed, 0);
1454                 }
1455         } else {
1456                 /* Check if we should immediately send eof on stdin. */
1457                 client_check_initial_eof_on_stdin();
1458         }
1459
1460         /* Main loop of the client for the interactive session mode. */
1461         while (!quit_pending) {
1462
1463                 /* Process buffered packets sent by the server. */
1464                 client_process_buffered_input_packets();
1465
1466                 if (compat20 && session_closed && !channel_still_open())
1467                         break;
1468
1469                 rekeying = (xxx_kex != NULL && !xxx_kex->done);
1470
1471                 if (rekeying) {
1472                         debug("rekeying in progress");
1473                 } else {
1474                         /*
1475                          * Make packets of buffered stdin data, and buffer
1476                          * them for sending to the server.
1477                          */
1478                         if (!compat20)
1479                                 client_make_packets_from_stdin_data();
1480
1481                         /*
1482                          * Make packets from buffered channel data, and
1483                          * enqueue them for sending to the server.
1484                          */
1485                         if (packet_not_very_much_data_to_write())
1486                                 channel_output_poll();
1487
1488                         /*
1489                          * Check if the window size has changed, and buffer a
1490                          * message about it to the server if so.
1491                          */
1492                         client_check_window_change();
1493
1494                         if (quit_pending)
1495                                 break;
1496                 }
1497                 /*
1498                  * Wait until we have something to do (something becomes
1499                  * available on one of the descriptors).
1500                  */
1501                 max_fd2 = max_fd;
1502                 client_wait_until_can_do_something(&readset, &writeset,
1503                     &max_fd2, &nalloc, rekeying);
1504
1505                 if (quit_pending)
1506                         break;
1507
1508                 /* Do channel operations unless rekeying in progress. */
1509                 if (!rekeying) {
1510                         channel_after_select(readset, writeset);
1511                         if (need_rekeying || packet_need_rekeying()) {
1512                                 debug("need rekeying");
1513                                 xxx_kex->done = 0;
1514                                 kex_send_kexinit(xxx_kex);
1515                                 need_rekeying = 0;
1516                         }
1517                 }
1518
1519                 /* Buffer input from the connection.  */
1520                 client_process_net_input(readset);
1521
1522                 if (quit_pending)
1523                         break;
1524
1525                 if (!compat20) {
1526                         /* Buffer data from stdin */
1527                         client_process_input(readset);
1528                         /*
1529                          * Process output to stdout and stderr.  Output to
1530                          * the connection is processed elsewhere (above).
1531                          */
1532                         client_process_output(writeset);
1533                 }
1534
1535                 if (session_resumed) {
1536                         connection_in = packet_get_connection_in();
1537                         connection_out = packet_get_connection_out();
1538                         max_fd = MAX(max_fd, connection_out);
1539                         max_fd = MAX(max_fd, connection_in);
1540                         session_resumed = 0;
1541                 }
1542
1543                 /*
1544                  * Send as much buffered packet data as possible to the
1545                  * sender.
1546                  */
1547                 if (FD_ISSET(connection_out, writeset))
1548                         packet_write_poll();
1549
1550                 /*
1551                  * If we are a backgrounded control master, and the
1552                  * timeout has expired without any active client
1553                  * connections, then quit.
1554                  */
1555                 if (control_persist_exit_time > 0) {
1556                         if (time(NULL) >= control_persist_exit_time) {
1557                                 debug("ControlPersist timeout expired");
1558                                 break;
1559                         }
1560                 }
1561         }
1562         if (readset)
1563                 xfree(readset);
1564         if (writeset)
1565                 xfree(writeset);
1566
1567         /* Terminate the session. */
1568
1569         /* Stop watching for window change. */
1570         signal(SIGWINCH, SIG_DFL);
1571
1572         if (compat20) {
1573                 packet_start(SSH2_MSG_DISCONNECT);
1574                 packet_put_int(SSH2_DISCONNECT_BY_APPLICATION);
1575                 packet_put_cstring("disconnected by user");
1576                 packet_put_cstring(""); /* language tag */
1577                 packet_send();
1578                 packet_write_wait();
1579         }
1580
1581         channel_free_all();
1582
1583         if (have_pty)
1584                 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1585
1586         /* restore blocking io */
1587         if (!isatty(fileno(stdin)))
1588                 unset_nonblock(fileno(stdin));
1589         if (!isatty(fileno(stdout)))
1590                 unset_nonblock(fileno(stdout));
1591         if (!isatty(fileno(stderr)))
1592                 unset_nonblock(fileno(stderr));
1593
1594         /*
1595          * If there was no shell or command requested, there will be no remote
1596          * exit status to be returned.  In that case, clear error code if the
1597          * connection was deliberately terminated at this end.
1598          */
1599         if (no_shell_flag && received_signal == SIGTERM) {
1600                 received_signal = 0;
1601                 exit_status = 0;
1602         }
1603
1604         if (received_signal)
1605                 fatal("Killed by signal %d.", (int) received_signal);
1606
1607         /*
1608          * In interactive mode (with pseudo tty) display a message indicating
1609          * that the connection has been closed.
1610          */
1611         if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1612                 snprintf(buf, sizeof buf,
1613                     "Connection to %.64s closed.\r\n", host);
1614                 buffer_append(&stderr_buffer, buf, strlen(buf));
1615         }
1616
1617         /* Output any buffered data for stdout. */
1618         if (buffer_len(&stdout_buffer) > 0) {
1619                 len = atomicio(vwrite, fileno(stdout),
1620                     buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer));
1621                 if (len < 0 || (u_int)len != buffer_len(&stdout_buffer))
1622                         error("Write failed flushing stdout buffer.");
1623                 else
1624                         buffer_consume(&stdout_buffer, len);
1625         }
1626
1627         /* Output any buffered data for stderr. */
1628         if (buffer_len(&stderr_buffer) > 0) {
1629                 len = atomicio(vwrite, fileno(stderr),
1630                     buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
1631                 if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
1632                         error("Write failed flushing stderr buffer.");
1633                 else
1634                         buffer_consume(&stderr_buffer, len);
1635         }
1636
1637         /* Clear and free any buffers. */
1638         memset(buf, 0, sizeof(buf));
1639         buffer_free(&stdin_buffer);
1640         buffer_free(&stdout_buffer);
1641         buffer_free(&stderr_buffer);
1642
1643         /* Report bytes transferred, and transfer rates. */
1644         total_time = get_current_time() - start_time;
1645         packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
1646         packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
1647         verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
1648             (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
1649         if (total_time > 0)
1650                 verbose("Bytes per second: sent %.1f, received %.1f",
1651                     obytes / total_time, ibytes / total_time);
1652         /* Return the exit status of the program. */
1653         debug("Exit status %d", exit_status);
1654         return exit_status;
1655 }
1656
1657 /*********/
1658
1659 static void
1660 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1661 {
1662         u_int data_len;
1663         char *data = packet_get_string(&data_len);
1664         packet_check_eom();
1665         buffer_append(&stdout_buffer, data, data_len);
1666         memset(data, 0, data_len);
1667         xfree(data);
1668 }
1669 static void
1670 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1671 {
1672         u_int data_len;
1673         char *data = packet_get_string(&data_len);
1674         packet_check_eom();
1675         buffer_append(&stderr_buffer, data, data_len);
1676         memset(data, 0, data_len);
1677         xfree(data);
1678 }
1679 static void
1680 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1681 {
1682         exit_status = packet_get_int();
1683         packet_check_eom();
1684         /* Acknowledge the exit. */
1685         packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1686         packet_send();
1687         /*
1688          * Must wait for packet to be sent since we are
1689          * exiting the loop.
1690          */
1691         packet_write_wait();
1692         /* Flag that we want to exit. */
1693         quit_pending = 1;
1694 }
1695 static void
1696 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1697 {
1698         Channel *c = NULL;
1699         int remote_id, sock;
1700
1701         /* Read the remote channel number from the message. */
1702         remote_id = packet_get_int();
1703         packet_check_eom();
1704
1705         /*
1706          * Get a connection to the local authentication agent (this may again
1707          * get forwarded).
1708          */
1709         sock = ssh_get_authentication_socket();
1710
1711         /*
1712          * If we could not connect the agent, send an error message back to
1713          * the server. This should never happen unless the agent dies,
1714          * because authentication forwarding is only enabled if we have an
1715          * agent.
1716          */
1717         if (sock >= 0) {
1718                 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1719                     -1, 0, 0, 0, "authentication agent connection", 1);
1720                 c->remote_id = remote_id;
1721                 c->force_drain = 1;
1722         }
1723         if (c == NULL) {
1724                 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1725                 packet_put_int(remote_id);
1726         } else {
1727                 /* Send a confirmation to the remote host. */
1728                 debug("Forwarding authentication connection.");
1729                 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1730                 packet_put_int(remote_id);
1731                 packet_put_int(c->self);
1732         }
1733         packet_send();
1734 }
1735
1736 static Channel *
1737 client_request_forwarded_tcpip(const char *request_type, int rchan)
1738 {
1739         Channel *c = NULL;
1740         char *listen_address, *originator_address;
1741         u_short listen_port, originator_port;
1742
1743         /* Get rest of the packet */
1744         listen_address = packet_get_string(NULL);
1745         listen_port = packet_get_int();
1746         originator_address = packet_get_string(NULL);
1747         originator_port = packet_get_int();
1748         packet_check_eom();
1749
1750         debug("client_request_forwarded_tcpip: listen %s port %d, "
1751             "originator %s port %d", listen_address, listen_port,
1752             originator_address, originator_port);
1753
1754         c = channel_connect_by_listen_address(listen_port,
1755             "forwarded-tcpip", originator_address);
1756
1757         xfree(originator_address);
1758         xfree(listen_address);
1759         return c;
1760 }
1761
1762 static Channel *
1763 client_request_x11(const char *request_type, int rchan)
1764 {
1765         Channel *c = NULL;
1766         char *originator;
1767         u_short originator_port;
1768         int sock;
1769
1770         if (!options.forward_x11) {
1771                 error("Warning: ssh server tried X11 forwarding.");
1772                 error("Warning: this is probably a break-in attempt by a "
1773                     "malicious server.");
1774                 return NULL;
1775         }
1776         if (x11_refuse_time != 0 && time(NULL) >= x11_refuse_time) {
1777                 verbose("Rejected X11 connection after ForwardX11Timeout "
1778                     "expired");
1779                 return NULL;
1780         }
1781         originator = packet_get_string(NULL);
1782         if (datafellows & SSH_BUG_X11FWD) {
1783                 debug2("buggy server: x11 request w/o originator_port");
1784                 originator_port = 0;
1785         } else {
1786                 originator_port = packet_get_int();
1787         }
1788         packet_check_eom();
1789         /* XXX check permission */
1790         debug("client_request_x11: request from %s %d", originator,
1791             originator_port);
1792         xfree(originator);
1793         sock = x11_connect_display();
1794         if (sock < 0)
1795                 return NULL;
1796         /* again is this really necessary for X11? */
1797         if (options.hpn_disabled)
1798         c = channel_new("x11",
1799             SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1800             CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1801         else
1802                 c = channel_new("x11",
1803                     SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1804                     options.hpn_buffer_size, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1805         c->force_drain = 1;
1806         return c;
1807 }
1808
1809 static Channel *
1810 client_request_agent(const char *request_type, int rchan)
1811 {
1812         Channel *c = NULL;
1813         int sock;
1814
1815         if (!options.forward_agent) {
1816                 error("Warning: ssh server tried agent forwarding.");
1817                 error("Warning: this is probably a break-in attempt by a "
1818                     "malicious server.");
1819                 return NULL;
1820         }
1821         sock = ssh_get_authentication_socket();
1822         if (sock < 0)
1823                 return NULL;
1824         if (options.hpn_disabled)
1825         c = channel_new("authentication agent connection",
1826             SSH_CHANNEL_OPEN, sock, sock, -1,
1827                     CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1828                     "authentication agent connection", 1);
1829        else
1830         c = channel_new("authentication agent connection",
1831             SSH_CHANNEL_OPEN, sock, sock, -1,
1832                    options.hpn_buffer_size, options.hpn_buffer_size, 0,
1833             "authentication agent connection", 1);
1834         c->force_drain = 1;
1835         return c;
1836 }
1837
1838 int
1839 client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
1840 {
1841         Channel *c;
1842         int fd;
1843
1844         if (tun_mode == SSH_TUNMODE_NO)
1845                 return 0;
1846
1847         if (!compat20) {
1848                 error("Tunnel forwarding is not supported for protocol 1");
1849                 return -1;
1850         }
1851
1852         debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
1853
1854         /* Open local tunnel device */
1855         if ((fd = tun_open(local_tun, tun_mode)) == -1) {
1856                 error("Tunnel device open failed.");
1857                 return -1;
1858         }
1859
1860         if(options.hpn_disabled)
1861         c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1862                                 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1863                                 0, "tun", 1);
1864         else
1865         c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1866                                 options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT,
1867                                 0, "tun", 1);
1868         c->datagram = 1;
1869
1870
1871
1872 #if defined(SSH_TUN_FILTER)
1873         if (options.tun_open == SSH_TUNMODE_POINTOPOINT)
1874                 channel_register_filter(c->self, sys_tun_infilter,
1875                     sys_tun_outfilter, NULL, NULL);
1876 #endif
1877
1878         packet_start(SSH2_MSG_CHANNEL_OPEN);
1879         packet_put_cstring("tun@openssh.com");
1880         packet_put_int(c->self);
1881         packet_put_int(c->local_window_max);
1882         packet_put_int(c->local_maxpacket);
1883         packet_put_int(tun_mode);
1884         packet_put_int(remote_tun);
1885         packet_send();
1886
1887         return 0;
1888 }
1889
1890 /* XXXX move to generic input handler */
1891 static void
1892 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1893 {
1894         Channel *c = NULL;
1895         char *ctype;
1896         int rchan;
1897         u_int rmaxpack, rwindow, len;
1898
1899         ctype = packet_get_string(&len);
1900         rchan = packet_get_int();
1901         rwindow = packet_get_int();
1902         rmaxpack = packet_get_int();
1903
1904         debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1905             ctype, rchan, rwindow, rmaxpack);
1906
1907         if (strcmp(ctype, "forwarded-tcpip") == 0) {
1908                 c = client_request_forwarded_tcpip(ctype, rchan);
1909         } else if (strcmp(ctype, "x11") == 0) {
1910                 c = client_request_x11(ctype, rchan);
1911         } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1912                 c = client_request_agent(ctype, rchan);
1913         }
1914 /* XXX duplicate : */
1915         if (c != NULL) {
1916                 debug("confirm %s", ctype);
1917                 c->remote_id = rchan;
1918                 c->remote_window = rwindow;
1919                 c->remote_maxpacket = rmaxpack;
1920                 if (c->type != SSH_CHANNEL_CONNECTING) {
1921                         packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1922                         packet_put_int(c->remote_id);
1923                         packet_put_int(c->self);
1924                         packet_put_int(c->local_window);
1925                         packet_put_int(c->local_maxpacket);
1926                         packet_send();
1927                 }
1928         } else {
1929                 debug("failure %s", ctype);
1930                 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1931                 packet_put_int(rchan);
1932                 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1933                 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1934                         packet_put_cstring("open failed");
1935                         packet_put_cstring("");
1936                 }
1937                 packet_send();
1938         }
1939         xfree(ctype);
1940 }
1941 static void
1942 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1943 {
1944         Channel *c = NULL;
1945         int exitval, id, reply, success = 0;
1946         char *rtype;
1947
1948         id = packet_get_int();
1949         rtype = packet_get_string(NULL);
1950         reply = packet_get_char();
1951
1952         debug("client_input_channel_req: channel %d rtype %s reply %d",
1953             id, rtype, reply);
1954
1955         if (id == -1) {
1956                 error("client_input_channel_req: request for channel -1");
1957         } else if ((c = channel_lookup(id)) == NULL) {
1958                 error("client_input_channel_req: channel %d: "
1959                     "unknown channel", id);
1960         } else if (strcmp(rtype, "eow@openssh.com") == 0) {
1961                 packet_check_eom();
1962                 chan_rcvd_eow(c);
1963         } else if (strcmp(rtype, "exit-status") == 0) {
1964                 exitval = packet_get_int();
1965                 if (c->ctl_chan != -1) {
1966                         mux_exit_message(c, exitval);
1967                         success = 1;
1968                 } else if (id == session_ident) {
1969                         /* Record exit value of local session */
1970                         success = 1;
1971                         exit_status = exitval;
1972                 } else {
1973                         /* Probably for a mux channel that has already closed */
1974                         debug("%s: no sink for exit-status on channel %d",
1975                             __func__, id);
1976                 }
1977                 packet_check_eom();
1978         }
1979         if (reply && c != NULL) {
1980                 packet_start(success ?
1981                     SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1982                 packet_put_int(c->remote_id);
1983                 packet_send();
1984         }
1985         xfree(rtype);
1986 }
1987 static void
1988 client_input_global_request(int type, u_int32_t seq, void *ctxt)
1989 {
1990         char *rtype;
1991         int want_reply;
1992         int success = 0;
1993
1994         rtype = packet_get_string(NULL);
1995         want_reply = packet_get_char();
1996         debug("client_input_global_request: rtype %s want_reply %d",
1997             rtype, want_reply);
1998         if (want_reply) {
1999                 packet_start(success ?
2000                     SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
2001                 packet_send();
2002                 packet_write_wait();
2003         }
2004         xfree(rtype);
2005 }
2006
2007 void
2008 client_session2_setup(int id, int want_tty, int want_subsystem,
2009     const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
2010 {
2011         int len;
2012         Channel *c = NULL;
2013
2014         debug2("%s: id %d", __func__, id);
2015
2016         if ((c = channel_lookup(id)) == NULL)
2017                 fatal("client_session2_setup: channel %d: unknown channel", id);
2018
2019         packet_set_interactive(want_tty,
2020             options.ip_qos_interactive, options.ip_qos_bulk);
2021
2022         if (want_tty) {
2023                 struct winsize ws;
2024
2025                 /* Store window size in the packet. */
2026                 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
2027                         memset(&ws, 0, sizeof(ws));
2028
2029                 channel_request_start(id, "pty-req", 1);
2030                 client_expect_confirm(id, "PTY allocation", CONFIRM_TTY);
2031                 packet_put_cstring(term != NULL ? term : "");
2032                 packet_put_int((u_int)ws.ws_col);
2033                 packet_put_int((u_int)ws.ws_row);
2034                 packet_put_int((u_int)ws.ws_xpixel);
2035                 packet_put_int((u_int)ws.ws_ypixel);
2036                 if (tiop == NULL)
2037                         tiop = get_saved_tio();
2038                 tty_make_modes(-1, tiop);
2039                 packet_send();
2040                 /* XXX wait for reply */
2041                 c->client_tty = 1;
2042         }
2043
2044         /* Transfer any environment variables from client to server */
2045         if (options.num_send_env != 0 && env != NULL) {
2046                 int i, j, matched;
2047                 char *name, *val;
2048
2049                 debug("Sending environment.");
2050                 for (i = 0; env[i] != NULL; i++) {
2051                         /* Split */
2052                         name = xstrdup(env[i]);
2053                         if ((val = strchr(name, '=')) == NULL) {
2054                                 xfree(name);
2055                                 continue;
2056                         }
2057                         *val++ = '\0';
2058
2059                         matched = 0;
2060                         for (j = 0; j < options.num_send_env; j++) {
2061                                 if (match_pattern(name, options.send_env[j])) {
2062                                         matched = 1;
2063                                         break;
2064                                 }
2065                         }
2066                         if (!matched) {
2067                                 debug3("Ignored env %s", name);
2068                                 xfree(name);
2069                                 continue;
2070                         }
2071
2072                         debug("Sending env %s = %s", name, val);
2073                         channel_request_start(id, "env", 0);
2074                         packet_put_cstring(name);
2075                         packet_put_cstring(val);
2076                         packet_send();
2077                         xfree(name);
2078                 }
2079         }
2080
2081         len = buffer_len(cmd);
2082         if (len > 0) {
2083                 if (len > 900)
2084                         len = 900;
2085                 if (want_subsystem) {
2086                         debug("Sending subsystem: %.*s",
2087                             len, (u_char*)buffer_ptr(cmd));
2088                         channel_request_start(id, "subsystem", 1);
2089                         client_expect_confirm(id, "subsystem", CONFIRM_CLOSE);
2090                 } else {
2091                         debug("Sending command: %.*s",
2092                             len, (u_char*)buffer_ptr(cmd));
2093                         channel_request_start(id, "exec", 1);
2094                         client_expect_confirm(id, "exec", CONFIRM_CLOSE);
2095                 }
2096                 packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
2097                 packet_send();
2098         } else {
2099                 channel_request_start(id, "shell", 1);
2100                 client_expect_confirm(id, "shell", CONFIRM_CLOSE);
2101                 packet_send();
2102         }
2103 }
2104
2105 static void
2106 client_init_dispatch_20(void)
2107 {
2108         dispatch_init(&dispatch_protocol_error);
2109
2110         dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
2111         dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
2112         dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
2113         dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
2114         dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
2115         dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2116         dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2117         dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
2118         dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
2119         dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
2120         dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
2121         dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
2122
2123         /* rekeying */
2124         dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
2125
2126         /* global request reply messages */
2127         dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
2128         dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
2129 }
2130
2131 static void
2132 client_init_dispatch_13(void)
2133 {
2134         dispatch_init(NULL);
2135         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
2136         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
2137         dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
2138         dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2139         dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2140         dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2141         dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2142         dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2143         dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
2144
2145         dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
2146             &client_input_agent_open : &deny_input_open);
2147         dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2148             &x11_input_open : &deny_input_open);
2149 }
2150
2151 static void
2152 client_init_dispatch_15(void)
2153 {
2154         client_init_dispatch_13();
2155         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2156         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2157 }
2158
2159 static void
2160 client_init_dispatch(void)
2161 {
2162         if (compat20)
2163                 client_init_dispatch_20();
2164         else if (compat13)
2165                 client_init_dispatch_13();
2166         else
2167                 client_init_dispatch_15();
2168 }
2169
2170 void
2171 client_stop_mux(void)
2172 {
2173         if (options.control_path != NULL && muxserver_sock != -1)
2174                 unlink(options.control_path);
2175         /*
2176          * If we are in persist mode, signal that we should close when all
2177          * active channels are closed.
2178          */
2179         if (options.control_persist) {
2180                 session_closed = 1;
2181                 setproctitle("[stopped mux]");
2182         }
2183 }
2184
2185 /* client specific fatal cleanup */
2186 void
2187 cleanup_exit(int i)
2188 {
2189         leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
2190         leave_non_blocking();
2191         if (options.control_path != NULL && muxserver_sock != -1)
2192                 unlink(options.control_path);
2193         ssh_kill_proxy_command();
2194         _exit(i);
2195 }