1 /* $OpenBSD: clientloop.c,v 1.240 2012/06/20 04:42:58 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_VALID_DISPLAY_CHARS ":/.-_" 285 static int 286 client_x11_display_valid(const char *display) 287 { 288 size_t i, dlen; 289 290 dlen = strlen(display); 291 for (i = 0; i < dlen; i++) { 292 if (!isalnum(display[i]) && 293 strchr(SSH_X11_VALID_DISPLAY_CHARS, display[i]) == NULL) { 294 debug("Invalid character '%c' in DISPLAY", display[i]); 295 return 0; 296 } 297 } 298 return 1; 299 } 300 301 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1" 302 void 303 client_x11_get_proto(const char *display, const char *xauth_path, 304 u_int trusted, u_int timeout, char **_proto, char **_data) 305 { 306 char cmd[1024]; 307 char line[512]; 308 char xdisplay[512]; 309 static char proto[512], data[512]; 310 FILE *f; 311 int got_data = 0, generated = 0, do_unlink = 0, i; 312 char *xauthdir, *xauthfile; 313 struct stat st; 314 u_int now; 315 316 xauthdir = xauthfile = NULL; 317 *_proto = proto; 318 *_data = data; 319 proto[0] = data[0] = '\0'; 320 321 if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) { 322 debug("No xauth program."); 323 } else if (!client_x11_display_valid(display)) { 324 logit("DISPLAY '%s' invalid, falling back to fake xauth data", 325 display); 326 } else { 327 if (display == NULL) { 328 debug("x11_get_proto: DISPLAY not set"); 329 return; 330 } 331 /* 332 * Handle FamilyLocal case where $DISPLAY does 333 * not match an authorization entry. For this we 334 * just try "xauth list unix:displaynum.screennum". 335 * XXX: "localhost" match to determine FamilyLocal 336 * is not perfect. 337 */ 338 if (strncmp(display, "localhost:", 10) == 0) { 339 snprintf(xdisplay, sizeof(xdisplay), "unix:%s", 340 display + 10); 341 display = xdisplay; 342 } 343 if (trusted == 0) { 344 xauthdir = xmalloc(MAXPATHLEN); 345 xauthfile = xmalloc(MAXPATHLEN); 346 mktemp_proto(xauthdir, MAXPATHLEN); 347 if (mkdtemp(xauthdir) != NULL) { 348 do_unlink = 1; 349 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile", 350 xauthdir); 351 snprintf(cmd, sizeof(cmd), 352 "%s -f %s generate %s " SSH_X11_PROTO 353 " untrusted timeout %u 2>" _PATH_DEVNULL, 354 xauth_path, xauthfile, display, timeout); 355 debug2("x11_get_proto: %s", cmd); 356 if (system(cmd) == 0) 357 generated = 1; 358 if (x11_refuse_time == 0) { 359 now = time(NULL) + 1; 360 if (UINT_MAX - timeout < now) 361 x11_refuse_time = UINT_MAX; 362 else 363 x11_refuse_time = now + timeout; 364 } 365 } 366 } 367 368 /* 369 * When in untrusted mode, we read the cookie only if it was 370 * successfully generated as an untrusted one in the step 371 * above. 372 */ 373 if (trusted || generated) { 374 snprintf(cmd, sizeof(cmd), 375 "%s %s%s list %s 2>" _PATH_DEVNULL, 376 xauth_path, 377 generated ? "-f " : "" , 378 generated ? xauthfile : "", 379 display); 380 debug2("x11_get_proto: %s", cmd); 381 f = popen(cmd, "r"); 382 if (f && fgets(line, sizeof(line), f) && 383 sscanf(line, "%*s %511s %511s", proto, data) == 2) 384 got_data = 1; 385 if (f) 386 pclose(f); 387 } else 388 error("Warning: untrusted X11 forwarding setup failed: " 389 "xauth key data not generated"); 390 } 391 392 if (do_unlink) { 393 unlink(xauthfile); 394 rmdir(xauthdir); 395 } 396 if (xauthdir) 397 xfree(xauthdir); 398 if (xauthfile) 399 xfree(xauthfile); 400 401 /* 402 * If we didn't get authentication data, just make up some 403 * data. The forwarding code will check the validity of the 404 * response anyway, and substitute this data. The X11 405 * server, however, will ignore this fake data and use 406 * whatever authentication mechanisms it was using otherwise 407 * for the local connection. 408 */ 409 if (!got_data) { 410 u_int32_t rnd = 0; 411 412 logit("Warning: No xauth data; " 413 "using fake authentication data for X11 forwarding."); 414 strlcpy(proto, SSH_X11_PROTO, sizeof proto); 415 for (i = 0; i < 16; i++) { 416 if (i % 4 == 0) 417 rnd = arc4random(); 418 snprintf(data + 2 * i, sizeof data - 2 * i, "%02x", 419 rnd & 0xff); 420 rnd >>= 8; 421 } 422 } 423 } 424 425 /* 426 * This is called when the interactive is entered. This checks if there is 427 * an EOF coming on stdin. We must check this explicitly, as select() does 428 * not appear to wake up when redirecting from /dev/null. 429 */ 430 431 static void 432 client_check_initial_eof_on_stdin(void) 433 { 434 int len; 435 char buf[1]; 436 437 /* 438 * If standard input is to be "redirected from /dev/null", we simply 439 * mark that we have seen an EOF and send an EOF message to the 440 * server. Otherwise, we try to read a single character; it appears 441 * that for some files, such /dev/null, select() never wakes up for 442 * read for this descriptor, which means that we never get EOF. This 443 * way we will get the EOF if stdin comes from /dev/null or similar. 444 */ 445 if (stdin_null_flag) { 446 /* Fake EOF on stdin. */ 447 debug("Sending eof."); 448 stdin_eof = 1; 449 packet_start(SSH_CMSG_EOF); 450 packet_send(); 451 } else { 452 enter_non_blocking(); 453 454 /* Check for immediate EOF on stdin. */ 455 len = read(fileno(stdin), buf, 1); 456 if (len == 0) { 457 /* 458 * EOF. Record that we have seen it and send 459 * EOF to server. 460 */ 461 debug("Sending eof."); 462 stdin_eof = 1; 463 packet_start(SSH_CMSG_EOF); 464 packet_send(); 465 } else if (len > 0) { 466 /* 467 * Got data. We must store the data in the buffer, 468 * and also process it as an escape character if 469 * appropriate. 470 */ 471 if ((u_char) buf[0] == escape_char1) 472 escape_pending1 = 1; 473 else 474 buffer_append(&stdin_buffer, buf, 1); 475 } 476 leave_non_blocking(); 477 } 478 } 479 480 481 /* 482 * Make packets from buffered stdin data, and buffer them for sending to the 483 * connection. 484 */ 485 486 static void 487 client_make_packets_from_stdin_data(void) 488 { 489 u_int len; 490 491 /* Send buffered stdin data to the server. */ 492 while (buffer_len(&stdin_buffer) > 0 && 493 packet_not_very_much_data_to_write()) { 494 len = buffer_len(&stdin_buffer); 495 /* Keep the packets at reasonable size. */ 496 if (len > packet_get_maxsize()) 497 len = packet_get_maxsize(); 498 packet_start(SSH_CMSG_STDIN_DATA); 499 packet_put_string(buffer_ptr(&stdin_buffer), len); 500 packet_send(); 501 buffer_consume(&stdin_buffer, len); 502 /* If we have a pending EOF, send it now. */ 503 if (stdin_eof && buffer_len(&stdin_buffer) == 0) { 504 packet_start(SSH_CMSG_EOF); 505 packet_send(); 506 } 507 } 508 } 509 510 /* 511 * Checks if the client window has changed, and sends a packet about it to 512 * the server if so. The actual change is detected elsewhere (by a software 513 * interrupt on Unix); this just checks the flag and sends a message if 514 * appropriate. 515 */ 516 517 static void 518 client_check_window_change(void) 519 { 520 struct winsize ws; 521 522 if (! received_window_change_signal) 523 return; 524 /** XXX race */ 525 received_window_change_signal = 0; 526 527 debug2("client_check_window_change: changed"); 528 529 if (compat20) { 530 channel_send_window_changes(); 531 } else { 532 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) 533 return; 534 packet_start(SSH_CMSG_WINDOW_SIZE); 535 packet_put_int((u_int)ws.ws_row); 536 packet_put_int((u_int)ws.ws_col); 537 packet_put_int((u_int)ws.ws_xpixel); 538 packet_put_int((u_int)ws.ws_ypixel); 539 packet_send(); 540 } 541 } 542 543 static void 544 client_global_request_reply(int type, u_int32_t seq, void *ctxt) 545 { 546 struct global_confirm *gc; 547 548 if ((gc = TAILQ_FIRST(&global_confirms)) == NULL) 549 return; 550 if (gc->cb != NULL) 551 gc->cb(type, seq, gc->ctx); 552 if (--gc->ref_count <= 0) { 553 TAILQ_REMOVE(&global_confirms, gc, entry); 554 bzero(gc, sizeof(*gc)); 555 xfree(gc); 556 } 557 558 packet_set_alive_timeouts(0); 559 } 560 561 static void 562 server_alive_check(void) 563 { 564 if (packet_inc_alive_timeouts() > options.server_alive_count_max) { 565 logit("Timeout, server %s not responding.", host); 566 cleanup_exit(255); 567 } 568 packet_start(SSH2_MSG_GLOBAL_REQUEST); 569 packet_put_cstring("keepalive@openssh.com"); 570 packet_put_char(1); /* boolean: want reply */ 571 packet_send(); 572 /* Insert an empty placeholder to maintain ordering */ 573 client_register_global_confirm(NULL, NULL); 574 } 575 576 /* 577 * Waits until the client can do something (some data becomes available on 578 * one of the file descriptors). 579 */ 580 static void 581 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, 582 int *maxfdp, u_int *nallocp, int rekeying) 583 { 584 struct timeval tv, *tvp; 585 int timeout_secs; 586 time_t minwait_secs = 0; 587 int ret; 588 589 /* Add any selections by the channel mechanism. */ 590 channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 591 &minwait_secs, rekeying); 592 593 if (!compat20) { 594 /* Read from the connection, unless our buffers are full. */ 595 if (buffer_len(&stdout_buffer) < buffer_high && 596 buffer_len(&stderr_buffer) < buffer_high && 597 channel_not_very_much_buffered_data()) 598 FD_SET(connection_in, *readsetp); 599 /* 600 * Read from stdin, unless we have seen EOF or have very much 601 * buffered data to send to the server. 602 */ 603 if (!stdin_eof && packet_not_very_much_data_to_write()) 604 FD_SET(fileno(stdin), *readsetp); 605 606 /* Select stdout/stderr if have data in buffer. */ 607 if (buffer_len(&stdout_buffer) > 0) 608 FD_SET(fileno(stdout), *writesetp); 609 if (buffer_len(&stderr_buffer) > 0) 610 FD_SET(fileno(stderr), *writesetp); 611 } else { 612 /* channel_prepare_select could have closed the last channel */ 613 if (session_closed && !channel_still_open() && 614 !packet_have_data_to_write()) { 615 /* clear mask since we did not call select() */ 616 memset(*readsetp, 0, *nallocp); 617 memset(*writesetp, 0, *nallocp); 618 return; 619 } else { 620 FD_SET(connection_in, *readsetp); 621 } 622 } 623 624 /* Select server connection if have data to write to the server. */ 625 if (packet_have_data_to_write()) 626 FD_SET(connection_out, *writesetp); 627 628 /* 629 * Wait for something to happen. This will suspend the process until 630 * some selected descriptor can be read, written, or has some other 631 * event pending, or a timeout expires. 632 */ 633 634 timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */ 635 if (options.server_alive_interval > 0 && compat20) 636 timeout_secs = options.server_alive_interval; 637 set_control_persist_exit_time(); 638 if (control_persist_exit_time > 0) { 639 timeout_secs = MIN(timeout_secs, 640 control_persist_exit_time - time(NULL)); 641 if (timeout_secs < 0) 642 timeout_secs = 0; 643 } 644 if (minwait_secs != 0) 645 timeout_secs = MIN(timeout_secs, (int)minwait_secs); 646 if (timeout_secs == INT_MAX) 647 tvp = NULL; 648 else { 649 tv.tv_sec = timeout_secs; 650 tv.tv_usec = 0; 651 tvp = &tv; 652 } 653 654 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp); 655 if (ret < 0) { 656 char buf[100]; 657 658 /* 659 * We have to clear the select masks, because we return. 660 * We have to return, because the mainloop checks for the flags 661 * set by the signal handlers. 662 */ 663 memset(*readsetp, 0, *nallocp); 664 memset(*writesetp, 0, *nallocp); 665 666 if (errno == EINTR) 667 return; 668 /* Note: we might still have data in the buffers. */ 669 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno)); 670 buffer_append(&stderr_buffer, buf, strlen(buf)); 671 quit_pending = 1; 672 } else if (ret == 0) 673 server_alive_check(); 674 } 675 676 static void 677 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr) 678 { 679 /* Flush stdout and stderr buffers. */ 680 if (buffer_len(bout) > 0) 681 atomicio(vwrite, fileno(stdout), buffer_ptr(bout), 682 buffer_len(bout)); 683 if (buffer_len(berr) > 0) 684 atomicio(vwrite, fileno(stderr), buffer_ptr(berr), 685 buffer_len(berr)); 686 687 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 688 689 /* 690 * Free (and clear) the buffer to reduce the amount of data that gets 691 * written to swap. 692 */ 693 buffer_free(bin); 694 buffer_free(bout); 695 buffer_free(berr); 696 697 /* Send the suspend signal to the program itself. */ 698 kill(getpid(), SIGTSTP); 699 700 /* Reset window sizes in case they have changed */ 701 received_window_change_signal = 1; 702 703 /* OK, we have been continued by the user. Reinitialize buffers. */ 704 buffer_init(bin); 705 buffer_init(bout); 706 buffer_init(berr); 707 708 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 709 } 710 711 static void 712 client_process_net_input(fd_set *readset) 713 { 714 int len, cont = 0; 715 char buf[SSH_IOBUFSZ]; 716 717 /* 718 * Read input from the server, and add any such data to the buffer of 719 * the packet subsystem. 720 */ 721 if (FD_ISSET(connection_in, readset)) { 722 /* Read as much as possible. */ 723 len = roaming_read(connection_in, buf, sizeof(buf), &cont); 724 if (len == 0 && cont == 0) { 725 /* 726 * Received EOF. The remote host has closed the 727 * connection. 728 */ 729 snprintf(buf, sizeof buf, 730 "Connection to %.300s closed by remote host.\r\n", 731 host); 732 buffer_append(&stderr_buffer, buf, strlen(buf)); 733 quit_pending = 1; 734 return; 735 } 736 /* 737 * There is a kernel bug on Solaris that causes select to 738 * sometimes wake up even though there is no data available. 739 */ 740 if (len < 0 && 741 (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK)) 742 len = 0; 743 744 if (len < 0) { 745 /* 746 * An error has encountered. Perhaps there is a 747 * network problem. 748 */ 749 snprintf(buf, sizeof buf, 750 "Read from remote host %.300s: %.100s\r\n", 751 host, strerror(errno)); 752 buffer_append(&stderr_buffer, buf, strlen(buf)); 753 quit_pending = 1; 754 return; 755 } 756 packet_process_incoming(buf, len); 757 } 758 } 759 760 static void 761 client_status_confirm(int type, Channel *c, void *ctx) 762 { 763 struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx; 764 char errmsg[256]; 765 int tochan; 766 767 /* 768 * If a TTY was explicitly requested, then a failure to allocate 769 * one is fatal. 770 */ 771 if (cr->action == CONFIRM_TTY && 772 (options.request_tty == REQUEST_TTY_FORCE || 773 options.request_tty == REQUEST_TTY_YES)) 774 cr->action = CONFIRM_CLOSE; 775 776 /* XXX supress on mux _client_ quietmode */ 777 tochan = options.log_level >= SYSLOG_LEVEL_ERROR && 778 c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE; 779 780 if (type == SSH2_MSG_CHANNEL_SUCCESS) { 781 debug2("%s request accepted on channel %d", 782 cr->request_type, c->self); 783 } else if (type == SSH2_MSG_CHANNEL_FAILURE) { 784 if (tochan) { 785 snprintf(errmsg, sizeof(errmsg), 786 "%s request failed\r\n", cr->request_type); 787 } else { 788 snprintf(errmsg, sizeof(errmsg), 789 "%s request failed on channel %d", 790 cr->request_type, c->self); 791 } 792 /* If error occurred on primary session channel, then exit */ 793 if (cr->action == CONFIRM_CLOSE && c->self == session_ident) 794 fatal("%s", errmsg); 795 /* 796 * If error occurred on mux client, append to 797 * their stderr. 798 */ 799 if (tochan) { 800 buffer_append(&c->extended, errmsg, 801 strlen(errmsg)); 802 } else 803 error("%s", errmsg); 804 if (cr->action == CONFIRM_TTY) { 805 /* 806 * If a TTY allocation error occurred, then arrange 807 * for the correct TTY to leave raw mode. 808 */ 809 if (c->self == session_ident) 810 leave_raw_mode(0); 811 else 812 mux_tty_alloc_failed(c); 813 } else if (cr->action == CONFIRM_CLOSE) { 814 chan_read_failed(c); 815 chan_write_failed(c); 816 } 817 } 818 xfree(cr); 819 } 820 821 static void 822 client_abandon_status_confirm(Channel *c, void *ctx) 823 { 824 xfree(ctx); 825 } 826 827 void 828 client_expect_confirm(int id, const char *request, 829 enum confirm_action action) 830 { 831 struct channel_reply_ctx *cr = xmalloc(sizeof(*cr)); 832 833 cr->request_type = request; 834 cr->action = action; 835 836 channel_register_status_confirm(id, client_status_confirm, 837 client_abandon_status_confirm, cr); 838 } 839 840 void 841 client_register_global_confirm(global_confirm_cb *cb, void *ctx) 842 { 843 struct global_confirm *gc, *last_gc; 844 845 /* Coalesce identical callbacks */ 846 last_gc = TAILQ_LAST(&global_confirms, global_confirms); 847 if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) { 848 if (++last_gc->ref_count >= INT_MAX) 849 fatal("%s: last_gc->ref_count = %d", 850 __func__, last_gc->ref_count); 851 return; 852 } 853 854 gc = xmalloc(sizeof(*gc)); 855 gc->cb = cb; 856 gc->ctx = ctx; 857 gc->ref_count = 1; 858 TAILQ_INSERT_TAIL(&global_confirms, gc, entry); 859 } 860 861 static void 862 process_cmdline(void) 863 { 864 void (*handler)(int); 865 char *s, *cmd, *cancel_host; 866 int delete = 0, local = 0, remote = 0, dynamic = 0; 867 int cancel_port, ok; 868 Forward fwd; 869 870 bzero(&fwd, sizeof(fwd)); 871 fwd.listen_host = fwd.connect_host = NULL; 872 873 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 874 handler = signal(SIGINT, SIG_IGN); 875 cmd = s = read_passphrase("\r\nssh> ", RP_ECHO); 876 if (s == NULL) 877 goto out; 878 while (isspace(*s)) 879 s++; 880 if (*s == '-') 881 s++; /* Skip cmdline '-', if any */ 882 if (*s == '\0') 883 goto out; 884 885 if (*s == 'h' || *s == 'H' || *s == '?') { 886 logit("Commands:"); 887 logit(" -L[bind_address:]port:host:hostport " 888 "Request local forward"); 889 logit(" -R[bind_address:]port:host:hostport " 890 "Request remote forward"); 891 logit(" -D[bind_address:]port " 892 "Request dynamic forward"); 893 logit(" -KL[bind_address:]port " 894 "Cancel local forward"); 895 logit(" -KR[bind_address:]port " 896 "Cancel remote forward"); 897 logit(" -KD[bind_address:]port " 898 "Cancel dynamic forward"); 899 if (!options.permit_local_command) 900 goto out; 901 logit(" !args " 902 "Execute local command"); 903 goto out; 904 } 905 906 if (*s == '!' && options.permit_local_command) { 907 s++; 908 ssh_local_cmd(s); 909 goto out; 910 } 911 912 if (*s == 'K') { 913 delete = 1; 914 s++; 915 } 916 if (*s == 'L') 917 local = 1; 918 else if (*s == 'R') 919 remote = 1; 920 else if (*s == 'D') 921 dynamic = 1; 922 else { 923 logit("Invalid command."); 924 goto out; 925 } 926 927 if (delete && !compat20) { 928 logit("Not supported for SSH protocol version 1."); 929 goto out; 930 } 931 932 while (isspace(*++s)) 933 ; 934 935 /* XXX update list of forwards in options */ 936 if (delete) { 937 cancel_port = 0; 938 cancel_host = hpdelim(&s); /* may be NULL */ 939 if (s != NULL) { 940 cancel_port = a2port(s); 941 cancel_host = cleanhostname(cancel_host); 942 } else { 943 cancel_port = a2port(cancel_host); 944 cancel_host = NULL; 945 } 946 if (cancel_port <= 0) { 947 logit("Bad forwarding close port"); 948 goto out; 949 } 950 if (remote) 951 ok = channel_request_rforward_cancel(cancel_host, 952 cancel_port) == 0; 953 else if (dynamic) 954 ok = channel_cancel_lport_listener(cancel_host, 955 cancel_port, 0, options.gateway_ports) > 0; 956 else 957 ok = channel_cancel_lport_listener(cancel_host, 958 cancel_port, CHANNEL_CANCEL_PORT_STATIC, 959 options.gateway_ports) > 0; 960 if (!ok) { 961 logit("Unkown port forwarding."); 962 goto out; 963 } 964 logit("Canceled forwarding."); 965 } else { 966 if (!parse_forward(&fwd, s, dynamic, remote)) { 967 logit("Bad forwarding specification."); 968 goto out; 969 } 970 if (local || dynamic) { 971 if (channel_setup_local_fwd_listener(fwd.listen_host, 972 fwd.listen_port, fwd.connect_host, 973 fwd.connect_port, options.gateway_ports) < 0) { 974 logit("Port forwarding failed."); 975 goto out; 976 } 977 } else { 978 if (channel_request_remote_forwarding(fwd.listen_host, 979 fwd.listen_port, fwd.connect_host, 980 fwd.connect_port) < 0) { 981 logit("Port forwarding failed."); 982 goto out; 983 } 984 } 985 logit("Forwarding port."); 986 } 987 988 out: 989 signal(SIGINT, handler); 990 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 991 if (cmd) 992 xfree(cmd); 993 if (fwd.listen_host != NULL) 994 xfree(fwd.listen_host); 995 if (fwd.connect_host != NULL) 996 xfree(fwd.connect_host); 997 } 998 999 /* 1000 * Process the characters one by one, call with c==NULL for proto1 case. 1001 */ 1002 static int 1003 process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr, 1004 char *buf, int len) 1005 { 1006 char string[1024]; 1007 pid_t pid; 1008 int bytes = 0; 1009 u_int i; 1010 u_char ch; 1011 char *s; 1012 int *escape_pendingp, escape_char; 1013 struct escape_filter_ctx *efc; 1014 1015 if (c == NULL) { 1016 escape_pendingp = &escape_pending1; 1017 escape_char = escape_char1; 1018 } else { 1019 if (c->filter_ctx == NULL) 1020 return 0; 1021 efc = (struct escape_filter_ctx *)c->filter_ctx; 1022 escape_pendingp = &efc->escape_pending; 1023 escape_char = efc->escape_char; 1024 } 1025 1026 if (len <= 0) 1027 return (0); 1028 1029 for (i = 0; i < (u_int)len; i++) { 1030 /* Get one character at a time. */ 1031 ch = buf[i]; 1032 1033 if (*escape_pendingp) { 1034 /* We have previously seen an escape character. */ 1035 /* Clear the flag now. */ 1036 *escape_pendingp = 0; 1037 1038 /* Process the escaped character. */ 1039 switch (ch) { 1040 case '.': 1041 /* Terminate the connection. */ 1042 snprintf(string, sizeof string, "%c.\r\n", 1043 escape_char); 1044 buffer_append(berr, string, strlen(string)); 1045 1046 if (c && c->ctl_chan != -1) { 1047 chan_read_failed(c); 1048 chan_write_failed(c); 1049 return 0; 1050 } else 1051 quit_pending = 1; 1052 return -1; 1053 1054 case 'Z' - 64: 1055 /* XXX support this for mux clients */ 1056 if (c && c->ctl_chan != -1) { 1057 noescape: 1058 snprintf(string, sizeof string, 1059 "%c%c escape not available to " 1060 "multiplexed sessions\r\n", 1061 escape_char, ch); 1062 buffer_append(berr, string, 1063 strlen(string)); 1064 continue; 1065 } 1066 /* Suspend the program. Inform the user */ 1067 snprintf(string, sizeof string, 1068 "%c^Z [suspend ssh]\r\n", escape_char); 1069 buffer_append(berr, string, strlen(string)); 1070 1071 /* Restore terminal modes and suspend. */ 1072 client_suspend_self(bin, bout, berr); 1073 1074 /* We have been continued. */ 1075 continue; 1076 1077 case 'B': 1078 if (compat20) { 1079 snprintf(string, sizeof string, 1080 "%cB\r\n", escape_char); 1081 buffer_append(berr, string, 1082 strlen(string)); 1083 channel_request_start(session_ident, 1084 "break", 0); 1085 packet_put_int(1000); 1086 packet_send(); 1087 } 1088 continue; 1089 1090 case 'R': 1091 if (compat20) { 1092 if (datafellows & SSH_BUG_NOREKEY) 1093 logit("Server does not " 1094 "support re-keying"); 1095 else 1096 need_rekeying = 1; 1097 } 1098 continue; 1099 1100 case '&': 1101 if (c && c->ctl_chan != -1) 1102 goto noescape; 1103 /* 1104 * Detach the program (continue to serve 1105 * connections, but put in background and no 1106 * more new connections). 1107 */ 1108 /* Restore tty modes. */ 1109 leave_raw_mode( 1110 options.request_tty == REQUEST_TTY_FORCE); 1111 1112 /* Stop listening for new connections. */ 1113 channel_stop_listening(); 1114 1115 snprintf(string, sizeof string, 1116 "%c& [backgrounded]\n", escape_char); 1117 buffer_append(berr, string, strlen(string)); 1118 1119 /* Fork into background. */ 1120 pid = fork(); 1121 if (pid < 0) { 1122 error("fork: %.100s", strerror(errno)); 1123 continue; 1124 } 1125 if (pid != 0) { /* This is the parent. */ 1126 /* The parent just exits. */ 1127 exit(0); 1128 } 1129 /* The child continues serving connections. */ 1130 if (compat20) { 1131 buffer_append(bin, "\004", 1); 1132 /* fake EOF on stdin */ 1133 return -1; 1134 } else if (!stdin_eof) { 1135 /* 1136 * Sending SSH_CMSG_EOF alone does not 1137 * always appear to be enough. So we 1138 * try to send an EOF character first. 1139 */ 1140 packet_start(SSH_CMSG_STDIN_DATA); 1141 packet_put_string("\004", 1); 1142 packet_send(); 1143 /* Close stdin. */ 1144 stdin_eof = 1; 1145 if (buffer_len(bin) == 0) { 1146 packet_start(SSH_CMSG_EOF); 1147 packet_send(); 1148 } 1149 } 1150 continue; 1151 1152 case '?': 1153 if (c && c->ctl_chan != -1) { 1154 snprintf(string, sizeof string, 1155 "%c?\r\n\ 1156 Supported escape sequences:\r\n\ 1157 %c. - terminate session\r\n\ 1158 %cB - send a BREAK to the remote system\r\n\ 1159 %cR - Request rekey (SSH protocol 2 only)\r\n\ 1160 %c# - list forwarded connections\r\n\ 1161 %c? - this message\r\n\ 1162 %c%c - send the escape character by typing it twice\r\n\ 1163 (Note that escapes are only recognized immediately after newline.)\r\n", 1164 escape_char, escape_char, 1165 escape_char, escape_char, 1166 escape_char, escape_char, 1167 escape_char, escape_char); 1168 } else { 1169 snprintf(string, sizeof string, 1170 "%c?\r\n\ 1171 Supported escape sequences:\r\n\ 1172 %c. - terminate connection (and any multiplexed sessions)\r\n\ 1173 %cB - send a BREAK to the remote system\r\n\ 1174 %cC - open a command line\r\n\ 1175 %cR - Request rekey (SSH protocol 2 only)\r\n\ 1176 %c^Z - suspend ssh\r\n\ 1177 %c# - list forwarded connections\r\n\ 1178 %c& - background ssh (when waiting for connections to terminate)\r\n\ 1179 %c? - this message\r\n\ 1180 %c%c - send the escape character by typing it twice\r\n\ 1181 (Note that escapes are only recognized immediately after newline.)\r\n", 1182 escape_char, escape_char, 1183 escape_char, escape_char, 1184 escape_char, escape_char, 1185 escape_char, escape_char, 1186 escape_char, escape_char, 1187 escape_char); 1188 } 1189 buffer_append(berr, string, strlen(string)); 1190 continue; 1191 1192 case '#': 1193 snprintf(string, sizeof string, "%c#\r\n", 1194 escape_char); 1195 buffer_append(berr, string, strlen(string)); 1196 s = channel_open_message(); 1197 buffer_append(berr, s, strlen(s)); 1198 xfree(s); 1199 continue; 1200 1201 case 'C': 1202 if (c && c->ctl_chan != -1) 1203 goto noescape; 1204 process_cmdline(); 1205 continue; 1206 1207 default: 1208 if (ch != escape_char) { 1209 buffer_put_char(bin, escape_char); 1210 bytes++; 1211 } 1212 /* Escaped characters fall through here */ 1213 break; 1214 } 1215 } else { 1216 /* 1217 * The previous character was not an escape char. 1218 * Check if this is an escape. 1219 */ 1220 if (last_was_cr && ch == escape_char) { 1221 /* 1222 * It is. Set the flag and continue to 1223 * next character. 1224 */ 1225 *escape_pendingp = 1; 1226 continue; 1227 } 1228 } 1229 1230 /* 1231 * Normal character. Record whether it was a newline, 1232 * and append it to the buffer. 1233 */ 1234 last_was_cr = (ch == '\r' || ch == '\n'); 1235 buffer_put_char(bin, ch); 1236 bytes++; 1237 } 1238 return bytes; 1239 } 1240 1241 static void 1242 client_process_input(fd_set *readset) 1243 { 1244 int len; 1245 char buf[SSH_IOBUFSZ]; 1246 1247 /* Read input from stdin. */ 1248 if (FD_ISSET(fileno(stdin), readset)) { 1249 /* Read as much as possible. */ 1250 len = read(fileno(stdin), buf, sizeof(buf)); 1251 if (len < 0 && 1252 (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK)) 1253 return; /* we'll try again later */ 1254 if (len <= 0) { 1255 /* 1256 * Received EOF or error. They are treated 1257 * similarly, except that an error message is printed 1258 * if it was an error condition. 1259 */ 1260 if (len < 0) { 1261 snprintf(buf, sizeof buf, "read: %.100s\r\n", 1262 strerror(errno)); 1263 buffer_append(&stderr_buffer, buf, strlen(buf)); 1264 } 1265 /* Mark that we have seen EOF. */ 1266 stdin_eof = 1; 1267 /* 1268 * Send an EOF message to the server unless there is 1269 * data in the buffer. If there is data in the 1270 * buffer, no message will be sent now. Code 1271 * elsewhere will send the EOF when the buffer 1272 * becomes empty if stdin_eof is set. 1273 */ 1274 if (buffer_len(&stdin_buffer) == 0) { 1275 packet_start(SSH_CMSG_EOF); 1276 packet_send(); 1277 } 1278 } else if (escape_char1 == SSH_ESCAPECHAR_NONE) { 1279 /* 1280 * Normal successful read, and no escape character. 1281 * Just append the data to buffer. 1282 */ 1283 buffer_append(&stdin_buffer, buf, len); 1284 } else { 1285 /* 1286 * Normal, successful read. But we have an escape 1287 * character and have to process the characters one 1288 * by one. 1289 */ 1290 if (process_escapes(NULL, &stdin_buffer, 1291 &stdout_buffer, &stderr_buffer, buf, len) == -1) 1292 return; 1293 } 1294 } 1295 } 1296 1297 static void 1298 client_process_output(fd_set *writeset) 1299 { 1300 int len; 1301 char buf[100]; 1302 1303 /* Write buffered output to stdout. */ 1304 if (FD_ISSET(fileno(stdout), writeset)) { 1305 /* Write as much data as possible. */ 1306 len = write(fileno(stdout), buffer_ptr(&stdout_buffer), 1307 buffer_len(&stdout_buffer)); 1308 if (len <= 0) { 1309 if (errno == EINTR || errno == EAGAIN || 1310 errno == EWOULDBLOCK) 1311 len = 0; 1312 else { 1313 /* 1314 * An error or EOF was encountered. Put an 1315 * error message to stderr buffer. 1316 */ 1317 snprintf(buf, sizeof buf, 1318 "write stdout: %.50s\r\n", strerror(errno)); 1319 buffer_append(&stderr_buffer, buf, strlen(buf)); 1320 quit_pending = 1; 1321 return; 1322 } 1323 } 1324 /* Consume printed data from the buffer. */ 1325 buffer_consume(&stdout_buffer, len); 1326 } 1327 /* Write buffered output to stderr. */ 1328 if (FD_ISSET(fileno(stderr), writeset)) { 1329 /* Write as much data as possible. */ 1330 len = write(fileno(stderr), buffer_ptr(&stderr_buffer), 1331 buffer_len(&stderr_buffer)); 1332 if (len <= 0) { 1333 if (errno == EINTR || errno == EAGAIN || 1334 errno == EWOULDBLOCK) 1335 len = 0; 1336 else { 1337 /* 1338 * EOF or error, but can't even print 1339 * error message. 1340 */ 1341 quit_pending = 1; 1342 return; 1343 } 1344 } 1345 /* Consume printed characters from the buffer. */ 1346 buffer_consume(&stderr_buffer, len); 1347 } 1348 } 1349 1350 /* 1351 * Get packets from the connection input buffer, and process them as long as 1352 * there are packets available. 1353 * 1354 * Any unknown packets received during the actual 1355 * session cause the session to terminate. This is 1356 * intended to make debugging easier since no 1357 * confirmations are sent. Any compatible protocol 1358 * extensions must be negotiated during the 1359 * preparatory phase. 1360 */ 1361 1362 static void 1363 client_process_buffered_input_packets(void) 1364 { 1365 dispatch_run(DISPATCH_NONBLOCK, &quit_pending, 1366 compat20 ? xxx_kex : NULL); 1367 } 1368 1369 /* scan buf[] for '~' before sending data to the peer */ 1370 1371 /* Helper: allocate a new escape_filter_ctx and fill in its escape char */ 1372 void * 1373 client_new_escape_filter_ctx(int escape_char) 1374 { 1375 struct escape_filter_ctx *ret; 1376 1377 ret = xmalloc(sizeof(*ret)); 1378 ret->escape_pending = 0; 1379 ret->escape_char = escape_char; 1380 return (void *)ret; 1381 } 1382 1383 /* Free the escape filter context on channel free */ 1384 void 1385 client_filter_cleanup(int cid, void *ctx) 1386 { 1387 xfree(ctx); 1388 } 1389 1390 int 1391 client_simple_escape_filter(Channel *c, char *buf, int len) 1392 { 1393 if (c->extended_usage != CHAN_EXTENDED_WRITE) 1394 return 0; 1395 1396 return process_escapes(c, &c->input, &c->output, &c->extended, 1397 buf, len); 1398 } 1399 1400 static void 1401 client_channel_closed(int id, void *arg) 1402 { 1403 channel_cancel_cleanup(id); 1404 session_closed = 1; 1405 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 1406 } 1407 1408 /* 1409 * Implements the interactive session with the server. This is called after 1410 * the user has been authenticated, and a command has been started on the 1411 * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character 1412 * used as an escape character for terminating or suspending the session. 1413 */ 1414 1415 int 1416 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id) 1417 { 1418 fd_set *readset = NULL, *writeset = NULL; 1419 double start_time, total_time; 1420 int max_fd = 0, max_fd2 = 0, len, rekeying = 0; 1421 u_int64_t ibytes, obytes; 1422 u_int nalloc = 0; 1423 char buf[100]; 1424 1425 debug("Entering interactive session."); 1426 1427 start_time = get_current_time(); 1428 1429 /* Initialize variables. */ 1430 escape_pending1 = 0; 1431 last_was_cr = 1; 1432 exit_status = -1; 1433 stdin_eof = 0; 1434 buffer_high = 64 * 1024; 1435 connection_in = packet_get_connection_in(); 1436 connection_out = packet_get_connection_out(); 1437 max_fd = MAX(connection_in, connection_out); 1438 1439 if (!compat20) { 1440 /* enable nonblocking unless tty */ 1441 if (!isatty(fileno(stdin))) 1442 set_nonblock(fileno(stdin)); 1443 if (!isatty(fileno(stdout))) 1444 set_nonblock(fileno(stdout)); 1445 if (!isatty(fileno(stderr))) 1446 set_nonblock(fileno(stderr)); 1447 max_fd = MAX(max_fd, fileno(stdin)); 1448 max_fd = MAX(max_fd, fileno(stdout)); 1449 max_fd = MAX(max_fd, fileno(stderr)); 1450 } 1451 quit_pending = 0; 1452 escape_char1 = escape_char_arg; 1453 1454 /* Initialize buffers. */ 1455 buffer_init(&stdin_buffer); 1456 buffer_init(&stdout_buffer); 1457 buffer_init(&stderr_buffer); 1458 1459 client_init_dispatch(); 1460 1461 /* 1462 * Set signal handlers, (e.g. to restore non-blocking mode) 1463 * but don't overwrite SIG_IGN, matches behaviour from rsh(1) 1464 */ 1465 if (signal(SIGHUP, SIG_IGN) != SIG_IGN) 1466 signal(SIGHUP, signal_handler); 1467 if (signal(SIGINT, SIG_IGN) != SIG_IGN) 1468 signal(SIGINT, signal_handler); 1469 if (signal(SIGQUIT, SIG_IGN) != SIG_IGN) 1470 signal(SIGQUIT, signal_handler); 1471 if (signal(SIGTERM, SIG_IGN) != SIG_IGN) 1472 signal(SIGTERM, signal_handler); 1473 signal(SIGWINCH, window_change_handler); 1474 1475 if (have_pty) 1476 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 1477 1478 if (compat20) { 1479 session_ident = ssh2_chan_id; 1480 if (session_ident != -1) { 1481 if (escape_char_arg != SSH_ESCAPECHAR_NONE) { 1482 channel_register_filter(session_ident, 1483 client_simple_escape_filter, NULL, 1484 client_filter_cleanup, 1485 client_new_escape_filter_ctx( 1486 escape_char_arg)); 1487 } 1488 channel_register_cleanup(session_ident, 1489 client_channel_closed, 0); 1490 } 1491 } else { 1492 /* Check if we should immediately send eof on stdin. */ 1493 client_check_initial_eof_on_stdin(); 1494 } 1495 1496 /* Main loop of the client for the interactive session mode. */ 1497 while (!quit_pending) { 1498 1499 /* Process buffered packets sent by the server. */ 1500 client_process_buffered_input_packets(); 1501 1502 if (compat20 && session_closed && !channel_still_open()) 1503 break; 1504 1505 rekeying = (xxx_kex != NULL && !xxx_kex->done); 1506 1507 if (rekeying) { 1508 debug("rekeying in progress"); 1509 } else { 1510 /* 1511 * Make packets of buffered stdin data, and buffer 1512 * them for sending to the server. 1513 */ 1514 if (!compat20) 1515 client_make_packets_from_stdin_data(); 1516 1517 /* 1518 * Make packets from buffered channel data, and 1519 * enqueue them for sending to the server. 1520 */ 1521 if (packet_not_very_much_data_to_write()) 1522 channel_output_poll(); 1523 1524 /* 1525 * Check if the window size has changed, and buffer a 1526 * message about it to the server if so. 1527 */ 1528 client_check_window_change(); 1529 1530 if (quit_pending) 1531 break; 1532 } 1533 /* 1534 * Wait until we have something to do (something becomes 1535 * available on one of the descriptors). 1536 */ 1537 max_fd2 = max_fd; 1538 client_wait_until_can_do_something(&readset, &writeset, 1539 &max_fd2, &nalloc, rekeying); 1540 1541 if (quit_pending) 1542 break; 1543 1544 /* Do channel operations unless rekeying in progress. */ 1545 if (!rekeying) { 1546 channel_after_select(readset, writeset); 1547 if (need_rekeying || packet_need_rekeying()) { 1548 debug("need rekeying"); 1549 xxx_kex->done = 0; 1550 kex_send_kexinit(xxx_kex); 1551 need_rekeying = 0; 1552 } 1553 } 1554 1555 /* Buffer input from the connection. */ 1556 client_process_net_input(readset); 1557 1558 if (quit_pending) 1559 break; 1560 1561 if (!compat20) { 1562 /* Buffer data from stdin */ 1563 client_process_input(readset); 1564 /* 1565 * Process output to stdout and stderr. Output to 1566 * the connection is processed elsewhere (above). 1567 */ 1568 client_process_output(writeset); 1569 } 1570 1571 if (session_resumed) { 1572 connection_in = packet_get_connection_in(); 1573 connection_out = packet_get_connection_out(); 1574 max_fd = MAX(max_fd, connection_out); 1575 max_fd = MAX(max_fd, connection_in); 1576 session_resumed = 0; 1577 } 1578 1579 /* 1580 * Send as much buffered packet data as possible to the 1581 * sender. 1582 */ 1583 if (FD_ISSET(connection_out, writeset)) 1584 packet_write_poll(); 1585 1586 /* 1587 * If we are a backgrounded control master, and the 1588 * timeout has expired without any active client 1589 * connections, then quit. 1590 */ 1591 if (control_persist_exit_time > 0) { 1592 if (time(NULL) >= control_persist_exit_time) { 1593 debug("ControlPersist timeout expired"); 1594 break; 1595 } 1596 } 1597 } 1598 if (readset) 1599 xfree(readset); 1600 if (writeset) 1601 xfree(writeset); 1602 1603 /* Terminate the session. */ 1604 1605 /* Stop watching for window change. */ 1606 signal(SIGWINCH, SIG_DFL); 1607 1608 if (compat20) { 1609 packet_start(SSH2_MSG_DISCONNECT); 1610 packet_put_int(SSH2_DISCONNECT_BY_APPLICATION); 1611 packet_put_cstring("disconnected by user"); 1612 packet_put_cstring(""); /* language tag */ 1613 packet_send(); 1614 packet_write_wait(); 1615 } 1616 1617 channel_free_all(); 1618 1619 if (have_pty) 1620 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 1621 1622 /* restore blocking io */ 1623 if (!isatty(fileno(stdin))) 1624 unset_nonblock(fileno(stdin)); 1625 if (!isatty(fileno(stdout))) 1626 unset_nonblock(fileno(stdout)); 1627 if (!isatty(fileno(stderr))) 1628 unset_nonblock(fileno(stderr)); 1629 1630 /* 1631 * If there was no shell or command requested, there will be no remote 1632 * exit status to be returned. In that case, clear error code if the 1633 * connection was deliberately terminated at this end. 1634 */ 1635 if (no_shell_flag && received_signal == SIGTERM) { 1636 received_signal = 0; 1637 exit_status = 0; 1638 } 1639 1640 if (received_signal) 1641 fatal("Killed by signal %d.", (int) received_signal); 1642 1643 /* 1644 * In interactive mode (with pseudo tty) display a message indicating 1645 * that the connection has been closed. 1646 */ 1647 if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) { 1648 snprintf(buf, sizeof buf, 1649 "Connection to %.64s closed.\r\n", host); 1650 buffer_append(&stderr_buffer, buf, strlen(buf)); 1651 } 1652 1653 /* Output any buffered data for stdout. */ 1654 if (buffer_len(&stdout_buffer) > 0) { 1655 len = atomicio(vwrite, fileno(stdout), 1656 buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer)); 1657 if (len < 0 || (u_int)len != buffer_len(&stdout_buffer)) 1658 error("Write failed flushing stdout buffer."); 1659 else 1660 buffer_consume(&stdout_buffer, len); 1661 } 1662 1663 /* Output any buffered data for stderr. */ 1664 if (buffer_len(&stderr_buffer) > 0) { 1665 len = atomicio(vwrite, fileno(stderr), 1666 buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer)); 1667 if (len < 0 || (u_int)len != buffer_len(&stderr_buffer)) 1668 error("Write failed flushing stderr buffer."); 1669 else 1670 buffer_consume(&stderr_buffer, len); 1671 } 1672 1673 /* Clear and free any buffers. */ 1674 memset(buf, 0, sizeof(buf)); 1675 buffer_free(&stdin_buffer); 1676 buffer_free(&stdout_buffer); 1677 buffer_free(&stderr_buffer); 1678 1679 /* Report bytes transferred, and transfer rates. */ 1680 total_time = get_current_time() - start_time; 1681 packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes); 1682 packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes); 1683 verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds", 1684 (unsigned long long)obytes, (unsigned long long)ibytes, total_time); 1685 if (total_time > 0) 1686 verbose("Bytes per second: sent %.1f, received %.1f", 1687 obytes / total_time, ibytes / total_time); 1688 /* Return the exit status of the program. */ 1689 debug("Exit status %d", exit_status); 1690 return exit_status; 1691 } 1692 1693 /*********/ 1694 1695 static void 1696 client_input_stdout_data(int type, u_int32_t seq, void *ctxt) 1697 { 1698 u_int data_len; 1699 char *data = packet_get_string(&data_len); 1700 packet_check_eom(); 1701 buffer_append(&stdout_buffer, data, data_len); 1702 memset(data, 0, data_len); 1703 xfree(data); 1704 } 1705 static void 1706 client_input_stderr_data(int type, u_int32_t seq, void *ctxt) 1707 { 1708 u_int data_len; 1709 char *data = packet_get_string(&data_len); 1710 packet_check_eom(); 1711 buffer_append(&stderr_buffer, data, data_len); 1712 memset(data, 0, data_len); 1713 xfree(data); 1714 } 1715 static void 1716 client_input_exit_status(int type, u_int32_t seq, void *ctxt) 1717 { 1718 exit_status = packet_get_int(); 1719 packet_check_eom(); 1720 /* Acknowledge the exit. */ 1721 packet_start(SSH_CMSG_EXIT_CONFIRMATION); 1722 packet_send(); 1723 /* 1724 * Must wait for packet to be sent since we are 1725 * exiting the loop. 1726 */ 1727 packet_write_wait(); 1728 /* Flag that we want to exit. */ 1729 quit_pending = 1; 1730 } 1731 static void 1732 client_input_agent_open(int type, u_int32_t seq, void *ctxt) 1733 { 1734 Channel *c = NULL; 1735 int remote_id, sock; 1736 1737 /* Read the remote channel number from the message. */ 1738 remote_id = packet_get_int(); 1739 packet_check_eom(); 1740 1741 /* 1742 * Get a connection to the local authentication agent (this may again 1743 * get forwarded). 1744 */ 1745 sock = ssh_get_authentication_socket(); 1746 1747 /* 1748 * If we could not connect the agent, send an error message back to 1749 * the server. This should never happen unless the agent dies, 1750 * because authentication forwarding is only enabled if we have an 1751 * agent. 1752 */ 1753 if (sock >= 0) { 1754 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, 1755 -1, 0, 0, 0, "authentication agent connection", 1); 1756 c->remote_id = remote_id; 1757 c->force_drain = 1; 1758 } 1759 if (c == NULL) { 1760 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); 1761 packet_put_int(remote_id); 1762 } else { 1763 /* Send a confirmation to the remote host. */ 1764 debug("Forwarding authentication connection."); 1765 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); 1766 packet_put_int(remote_id); 1767 packet_put_int(c->self); 1768 } 1769 packet_send(); 1770 } 1771 1772 static Channel * 1773 client_request_forwarded_tcpip(const char *request_type, int rchan) 1774 { 1775 Channel *c = NULL; 1776 char *listen_address, *originator_address; 1777 u_short listen_port, originator_port; 1778 1779 /* Get rest of the packet */ 1780 listen_address = packet_get_string(NULL); 1781 listen_port = packet_get_int(); 1782 originator_address = packet_get_string(NULL); 1783 originator_port = packet_get_int(); 1784 packet_check_eom(); 1785 1786 debug("client_request_forwarded_tcpip: listen %s port %d, " 1787 "originator %s port %d", listen_address, listen_port, 1788 originator_address, originator_port); 1789 1790 c = channel_connect_by_listen_address(listen_port, 1791 "forwarded-tcpip", originator_address); 1792 1793 xfree(originator_address); 1794 xfree(listen_address); 1795 return c; 1796 } 1797 1798 static Channel * 1799 client_request_x11(const char *request_type, int rchan) 1800 { 1801 Channel *c = NULL; 1802 char *originator; 1803 u_short originator_port; 1804 int sock; 1805 1806 if (!options.forward_x11) { 1807 error("Warning: ssh server tried X11 forwarding."); 1808 error("Warning: this is probably a break-in attempt by a " 1809 "malicious server."); 1810 return NULL; 1811 } 1812 if (x11_refuse_time != 0 && time(NULL) >= x11_refuse_time) { 1813 verbose("Rejected X11 connection after ForwardX11Timeout " 1814 "expired"); 1815 return NULL; 1816 } 1817 originator = packet_get_string(NULL); 1818 if (datafellows & SSH_BUG_X11FWD) { 1819 debug2("buggy server: x11 request w/o originator_port"); 1820 originator_port = 0; 1821 } else { 1822 originator_port = packet_get_int(); 1823 } 1824 packet_check_eom(); 1825 /* XXX check permission */ 1826 debug("client_request_x11: request from %s %d", originator, 1827 originator_port); 1828 xfree(originator); 1829 sock = x11_connect_display(); 1830 if (sock < 0) 1831 return NULL; 1832 /* again is this really necessary for X11? */ 1833 if (options.hpn_disabled) 1834 c = channel_new("x11", 1835 SSH_CHANNEL_X11_OPEN, sock, sock, -1, 1836 CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1); 1837 else 1838 c = channel_new("x11", 1839 SSH_CHANNEL_X11_OPEN, sock, sock, -1, 1840 options.hpn_buffer_size, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1); 1841 c->force_drain = 1; 1842 return c; 1843 } 1844 1845 static Channel * 1846 client_request_agent(const char *request_type, int rchan) 1847 { 1848 Channel *c = NULL; 1849 int sock; 1850 1851 if (!options.forward_agent) { 1852 error("Warning: ssh server tried agent forwarding."); 1853 error("Warning: this is probably a break-in attempt by a " 1854 "malicious server."); 1855 return NULL; 1856 } 1857 sock = ssh_get_authentication_socket(); 1858 if (sock < 0) 1859 return NULL; 1860 if (options.hpn_disabled) 1861 c = channel_new("authentication agent connection", 1862 SSH_CHANNEL_OPEN, sock, sock, -1, 1863 CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0, 1864 "authentication agent connection", 1); 1865 else 1866 c = channel_new("authentication agent connection", 1867 SSH_CHANNEL_OPEN, sock, sock, -1, 1868 options.hpn_buffer_size, options.hpn_buffer_size, 0, 1869 "authentication agent connection", 1); 1870 c->force_drain = 1; 1871 return c; 1872 } 1873 1874 int 1875 client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun) 1876 { 1877 Channel *c; 1878 int fd; 1879 1880 if (tun_mode == SSH_TUNMODE_NO) 1881 return 0; 1882 1883 if (!compat20) { 1884 error("Tunnel forwarding is not supported for protocol 1"); 1885 return -1; 1886 } 1887 1888 debug("Requesting tun unit %d in mode %d", local_tun, tun_mode); 1889 1890 /* Open local tunnel device */ 1891 if ((fd = tun_open(local_tun, tun_mode)) == -1) { 1892 error("Tunnel device open failed."); 1893 return -1; 1894 } 1895 1896 if(options.hpn_disabled) 1897 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1, 1898 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 1899 0, "tun", 1); 1900 else 1901 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1, 1902 options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT, 1903 0, "tun", 1); 1904 c->datagram = 1; 1905 1906 1907 1908 #if defined(SSH_TUN_FILTER) 1909 if (options.tun_open == SSH_TUNMODE_POINTOPOINT) 1910 channel_register_filter(c->self, sys_tun_infilter, 1911 sys_tun_outfilter, NULL, NULL); 1912 #endif 1913 1914 packet_start(SSH2_MSG_CHANNEL_OPEN); 1915 packet_put_cstring("tun@openssh.com"); 1916 packet_put_int(c->self); 1917 packet_put_int(c->local_window_max); 1918 packet_put_int(c->local_maxpacket); 1919 packet_put_int(tun_mode); 1920 packet_put_int(remote_tun); 1921 packet_send(); 1922 1923 return 0; 1924 } 1925 1926 /* XXXX move to generic input handler */ 1927 static void 1928 client_input_channel_open(int type, u_int32_t seq, void *ctxt) 1929 { 1930 Channel *c = NULL; 1931 char *ctype; 1932 int rchan; 1933 u_int rmaxpack, rwindow, len; 1934 1935 ctype = packet_get_string(&len); 1936 rchan = packet_get_int(); 1937 rwindow = packet_get_int(); 1938 rmaxpack = packet_get_int(); 1939 1940 debug("client_input_channel_open: ctype %s rchan %d win %d max %d", 1941 ctype, rchan, rwindow, rmaxpack); 1942 1943 if (strcmp(ctype, "forwarded-tcpip") == 0) { 1944 c = client_request_forwarded_tcpip(ctype, rchan); 1945 } else if (strcmp(ctype, "x11") == 0) { 1946 c = client_request_x11(ctype, rchan); 1947 } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) { 1948 c = client_request_agent(ctype, rchan); 1949 } 1950 /* XXX duplicate : */ 1951 if (c != NULL) { 1952 debug("confirm %s", ctype); 1953 c->remote_id = rchan; 1954 c->remote_window = rwindow; 1955 c->remote_maxpacket = rmaxpack; 1956 if (c->type != SSH_CHANNEL_CONNECTING) { 1957 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); 1958 packet_put_int(c->remote_id); 1959 packet_put_int(c->self); 1960 packet_put_int(c->local_window); 1961 packet_put_int(c->local_maxpacket); 1962 packet_send(); 1963 } 1964 } else { 1965 debug("failure %s", ctype); 1966 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); 1967 packet_put_int(rchan); 1968 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED); 1969 if (!(datafellows & SSH_BUG_OPENFAILURE)) { 1970 packet_put_cstring("open failed"); 1971 packet_put_cstring(""); 1972 } 1973 packet_send(); 1974 } 1975 xfree(ctype); 1976 } 1977 static void 1978 client_input_channel_req(int type, u_int32_t seq, void *ctxt) 1979 { 1980 Channel *c = NULL; 1981 int exitval, id, reply, success = 0; 1982 char *rtype; 1983 1984 id = packet_get_int(); 1985 rtype = packet_get_string(NULL); 1986 reply = packet_get_char(); 1987 1988 debug("client_input_channel_req: channel %d rtype %s reply %d", 1989 id, rtype, reply); 1990 1991 if (id == -1) { 1992 error("client_input_channel_req: request for channel -1"); 1993 } else if ((c = channel_lookup(id)) == NULL) { 1994 error("client_input_channel_req: channel %d: " 1995 "unknown channel", id); 1996 } else if (strcmp(rtype, "eow@openssh.com") == 0) { 1997 packet_check_eom(); 1998 chan_rcvd_eow(c); 1999 } else if (strcmp(rtype, "exit-status") == 0) { 2000 exitval = packet_get_int(); 2001 if (c->ctl_chan != -1) { 2002 mux_exit_message(c, exitval); 2003 success = 1; 2004 } else if (id == session_ident) { 2005 /* Record exit value of local session */ 2006 success = 1; 2007 exit_status = exitval; 2008 } else { 2009 /* Probably for a mux channel that has already closed */ 2010 debug("%s: no sink for exit-status on channel %d", 2011 __func__, id); 2012 } 2013 packet_check_eom(); 2014 } 2015 if (reply && c != NULL) { 2016 packet_start(success ? 2017 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE); 2018 packet_put_int(c->remote_id); 2019 packet_send(); 2020 } 2021 xfree(rtype); 2022 } 2023 static void 2024 client_input_global_request(int type, u_int32_t seq, void *ctxt) 2025 { 2026 char *rtype; 2027 int want_reply; 2028 int success = 0; 2029 2030 rtype = packet_get_string(NULL); 2031 want_reply = packet_get_char(); 2032 debug("client_input_global_request: rtype %s want_reply %d", 2033 rtype, want_reply); 2034 if (want_reply) { 2035 packet_start(success ? 2036 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE); 2037 packet_send(); 2038 packet_write_wait(); 2039 } 2040 xfree(rtype); 2041 } 2042 2043 void 2044 client_session2_setup(int id, int want_tty, int want_subsystem, 2045 const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env) 2046 { 2047 int len; 2048 Channel *c = NULL; 2049 2050 debug2("%s: id %d", __func__, id); 2051 2052 if ((c = channel_lookup(id)) == NULL) 2053 fatal("client_session2_setup: channel %d: unknown channel", id); 2054 2055 packet_set_interactive(want_tty, 2056 options.ip_qos_interactive, options.ip_qos_bulk); 2057 2058 if (want_tty) { 2059 struct winsize ws; 2060 2061 /* Store window size in the packet. */ 2062 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0) 2063 memset(&ws, 0, sizeof(ws)); 2064 2065 channel_request_start(id, "pty-req", 1); 2066 client_expect_confirm(id, "PTY allocation", CONFIRM_TTY); 2067 packet_put_cstring(term != NULL ? term : ""); 2068 packet_put_int((u_int)ws.ws_col); 2069 packet_put_int((u_int)ws.ws_row); 2070 packet_put_int((u_int)ws.ws_xpixel); 2071 packet_put_int((u_int)ws.ws_ypixel); 2072 if (tiop == NULL) 2073 tiop = get_saved_tio(); 2074 tty_make_modes(-1, tiop); 2075 packet_send(); 2076 /* XXX wait for reply */ 2077 c->client_tty = 1; 2078 } 2079 2080 /* Transfer any environment variables from client to server */ 2081 if (options.num_send_env != 0 && env != NULL) { 2082 int i, j, matched; 2083 char *name, *val; 2084 2085 debug("Sending environment."); 2086 for (i = 0; env[i] != NULL; i++) { 2087 /* Split */ 2088 name = xstrdup(env[i]); 2089 if ((val = strchr(name, '=')) == NULL) { 2090 xfree(name); 2091 continue; 2092 } 2093 *val++ = '\0'; 2094 2095 matched = 0; 2096 for (j = 0; j < options.num_send_env; j++) { 2097 if (match_pattern(name, options.send_env[j])) { 2098 matched = 1; 2099 break; 2100 } 2101 } 2102 if (!matched) { 2103 debug3("Ignored env %s", name); 2104 xfree(name); 2105 continue; 2106 } 2107 2108 debug("Sending env %s = %s", name, val); 2109 channel_request_start(id, "env", 0); 2110 packet_put_cstring(name); 2111 packet_put_cstring(val); 2112 packet_send(); 2113 xfree(name); 2114 } 2115 } 2116 2117 len = buffer_len(cmd); 2118 if (len > 0) { 2119 if (len > 900) 2120 len = 900; 2121 if (want_subsystem) { 2122 debug("Sending subsystem: %.*s", 2123 len, (u_char*)buffer_ptr(cmd)); 2124 channel_request_start(id, "subsystem", 1); 2125 client_expect_confirm(id, "subsystem", CONFIRM_CLOSE); 2126 } else { 2127 debug("Sending command: %.*s", 2128 len, (u_char*)buffer_ptr(cmd)); 2129 channel_request_start(id, "exec", 1); 2130 client_expect_confirm(id, "exec", CONFIRM_CLOSE); 2131 } 2132 packet_put_string(buffer_ptr(cmd), buffer_len(cmd)); 2133 packet_send(); 2134 } else { 2135 channel_request_start(id, "shell", 1); 2136 client_expect_confirm(id, "shell", CONFIRM_CLOSE); 2137 packet_send(); 2138 } 2139 } 2140 2141 static void 2142 client_init_dispatch_20(void) 2143 { 2144 dispatch_init(&dispatch_protocol_error); 2145 2146 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose); 2147 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data); 2148 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof); 2149 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data); 2150 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open); 2151 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); 2152 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); 2153 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req); 2154 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust); 2155 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm); 2156 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm); 2157 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request); 2158 2159 /* rekeying */ 2160 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit); 2161 2162 /* global request reply messages */ 2163 dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply); 2164 dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply); 2165 } 2166 2167 static void 2168 client_init_dispatch_13(void) 2169 { 2170 dispatch_init(NULL); 2171 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close); 2172 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation); 2173 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data); 2174 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); 2175 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); 2176 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open); 2177 dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status); 2178 dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data); 2179 dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data); 2180 2181 dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ? 2182 &client_input_agent_open : &deny_input_open); 2183 dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ? 2184 &x11_input_open : &deny_input_open); 2185 } 2186 2187 static void 2188 client_init_dispatch_15(void) 2189 { 2190 client_init_dispatch_13(); 2191 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof); 2192 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose); 2193 } 2194 2195 static void 2196 client_init_dispatch(void) 2197 { 2198 if (compat20) 2199 client_init_dispatch_20(); 2200 else if (compat13) 2201 client_init_dispatch_13(); 2202 else 2203 client_init_dispatch_15(); 2204 } 2205 2206 void 2207 client_stop_mux(void) 2208 { 2209 if (options.control_path != NULL && muxserver_sock != -1) 2210 unlink(options.control_path); 2211 /* 2212 * If we are in persist mode, signal that we should close when all 2213 * active channels are closed. 2214 */ 2215 if (options.control_persist) { 2216 session_closed = 1; 2217 setproctitle("[stopped mux]"); 2218 } 2219 } 2220 2221 /* client specific fatal cleanup */ 2222 void 2223 cleanup_exit(int i) 2224 { 2225 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 2226 leave_non_blocking(); 2227 if (options.control_path != NULL && muxserver_sock != -1) 2228 unlink(options.control_path); 2229 ssh_kill_proxy_command(); 2230 _exit(i); 2231 } 2232