1 /* $OpenBSD: clientloop.c,v 1.248 2013/01/02 00:32:07 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 63 #include <sys/types.h> 64 #include <sys/ioctl.h> 65 #include <sys/stat.h> 66 #include <sys/socket.h> 67 #include <sys/time.h> 68 #include <sys/param.h> 69 #include <sys/queue.h> 70 71 #include <ctype.h> 72 #include <errno.h> 73 #include <paths.h> 74 #include <signal.h> 75 #include <stdio.h> 76 #include <stdlib.h> 77 #include <string.h> 78 #include <termios.h> 79 #include <pwd.h> 80 #include <unistd.h> 81 82 #include "xmalloc.h" 83 #include "ssh.h" 84 #include "ssh1.h" 85 #include "ssh2.h" 86 #include "packet.h" 87 #include "buffer.h" 88 #include "compat.h" 89 #include "channels.h" 90 #include "dispatch.h" 91 #include "key.h" 92 #include "cipher.h" 93 #include "kex.h" 94 #include "log.h" 95 #include "readconf.h" 96 #include "clientloop.h" 97 #include "sshconnect.h" 98 #include "authfd.h" 99 #include "atomicio.h" 100 #include "sshpty.h" 101 #include "misc.h" 102 #include "match.h" 103 #include "msg.h" 104 #include "roaming.h" 105 106 /* import options */ 107 extern Options options; 108 109 /* Flag indicating that stdin should be redirected from /dev/null. */ 110 extern int stdin_null_flag; 111 112 /* Flag indicating that no shell has been requested */ 113 extern int no_shell_flag; 114 115 /* Control socket */ 116 extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */ 117 118 /* 119 * Name of the host we are connecting to. This is the name given on the 120 * command line, or the HostName specified for the user-supplied name in a 121 * configuration file. 122 */ 123 extern char *host; 124 125 /* 126 * Flag to indicate that we have received a window change signal which has 127 * not yet been processed. This will cause a message indicating the new 128 * window size to be sent to the server a little later. This is volatile 129 * because this is updated in a signal handler. 130 */ 131 static volatile sig_atomic_t received_window_change_signal = 0; 132 static volatile sig_atomic_t received_signal = 0; 133 134 /* Flag indicating whether the user's terminal is in non-blocking mode. */ 135 static int in_non_blocking_mode = 0; 136 137 /* Time when backgrounded control master using ControlPersist should exit */ 138 static time_t control_persist_exit_time = 0; 139 140 /* Common data for the client loop code. */ 141 volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */ 142 static int escape_char1; /* Escape character. (proto1 only) */ 143 static int escape_pending1; /* Last character was an escape (proto1 only) */ 144 static int last_was_cr; /* Last character was a newline. */ 145 static int exit_status; /* Used to store the command exit status. */ 146 static int stdin_eof; /* EOF has been encountered on stderr. */ 147 static Buffer stdin_buffer; /* Buffer for stdin data. */ 148 static Buffer stdout_buffer; /* Buffer for stdout data. */ 149 static Buffer stderr_buffer; /* Buffer for stderr data. */ 150 static u_int buffer_high; /* Soft max buffer size. */ 151 static int connection_in; /* Connection to server (input). */ 152 static int connection_out; /* Connection to server (output). */ 153 static int need_rekeying; /* Set to non-zero if rekeying is requested. */ 154 static int session_closed; /* In SSH2: login session closed. */ 155 static int x11_refuse_time; /* If >0, refuse x11 opens after this time. */ 156 157 static void client_init_dispatch(void); 158 int session_ident = -1; 159 160 int session_resumed = 0; 161 162 /* Track escape per proto2 channel */ 163 struct escape_filter_ctx { 164 int escape_pending; 165 int escape_char; 166 }; 167 168 /* Context for channel confirmation replies */ 169 struct channel_reply_ctx { 170 const char *request_type; 171 int id; 172 enum confirm_action action; 173 }; 174 175 /* Global request success/failure callbacks */ 176 struct global_confirm { 177 TAILQ_ENTRY(global_confirm) entry; 178 global_confirm_cb *cb; 179 void *ctx; 180 int ref_count; 181 }; 182 TAILQ_HEAD(global_confirms, global_confirm); 183 static struct global_confirms global_confirms = 184 TAILQ_HEAD_INITIALIZER(global_confirms); 185 186 /*XXX*/ 187 extern Kex *xxx_kex; 188 189 void ssh_process_session2_setup(int, int, int, Buffer *); 190 191 /* Restores stdin to blocking mode. */ 192 193 static void 194 leave_non_blocking(void) 195 { 196 if (in_non_blocking_mode) { 197 unset_nonblock(fileno(stdin)); 198 in_non_blocking_mode = 0; 199 } 200 } 201 202 /* Puts stdin terminal in non-blocking mode. */ 203 204 static void 205 enter_non_blocking(void) 206 { 207 in_non_blocking_mode = 1; 208 set_nonblock(fileno(stdin)); 209 } 210 211 /* 212 * Signal handler for the window change signal (SIGWINCH). This just sets a 213 * flag indicating that the window has changed. 214 */ 215 /*ARGSUSED */ 216 static void 217 window_change_handler(int sig) 218 { 219 received_window_change_signal = 1; 220 signal(SIGWINCH, window_change_handler); 221 } 222 223 /* 224 * Signal handler for signals that cause the program to terminate. These 225 * signals must be trapped to restore terminal modes. 226 */ 227 /*ARGSUSED */ 228 static void 229 signal_handler(int sig) 230 { 231 received_signal = sig; 232 quit_pending = 1; 233 } 234 235 /* 236 * Returns current time in seconds from Jan 1, 1970 with the maximum 237 * available resolution. 238 */ 239 240 static double 241 get_current_time(void) 242 { 243 struct timeval tv; 244 gettimeofday(&tv, NULL); 245 return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0; 246 } 247 248 /* 249 * Sets control_persist_exit_time to the absolute time when the 250 * backgrounded control master should exit due to expiry of the 251 * ControlPersist timeout. Sets it to 0 if we are not a backgrounded 252 * control master process, or if there is no ControlPersist timeout. 253 */ 254 static void 255 set_control_persist_exit_time(void) 256 { 257 if (muxserver_sock == -1 || !options.control_persist 258 || options.control_persist_timeout == 0) { 259 /* not using a ControlPersist timeout */ 260 control_persist_exit_time = 0; 261 } else if (channel_still_open()) { 262 /* some client connections are still open */ 263 if (control_persist_exit_time > 0) 264 debug2("%s: cancel scheduled exit", __func__); 265 control_persist_exit_time = 0; 266 } else if (control_persist_exit_time <= 0) { 267 /* a client connection has recently closed */ 268 control_persist_exit_time = time(NULL) + 269 (time_t)options.control_persist_timeout; 270 debug2("%s: schedule exit in %d seconds", __func__, 271 options.control_persist_timeout); 272 } 273 /* else we are already counting down to the timeout */ 274 } 275 276 #define SSH_X11_VALID_DISPLAY_CHARS ":/.-_" 277 static int 278 client_x11_display_valid(const char *display) 279 { 280 size_t i, dlen; 281 282 dlen = strlen(display); 283 for (i = 0; i < dlen; i++) { 284 if (!isalnum(display[i]) && 285 strchr(SSH_X11_VALID_DISPLAY_CHARS, display[i]) == NULL) { 286 debug("Invalid character '%c' in DISPLAY", display[i]); 287 return 0; 288 } 289 } 290 return 1; 291 } 292 293 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1" 294 void 295 client_x11_get_proto(const char *display, const char *xauth_path, 296 u_int trusted, u_int timeout, char **_proto, char **_data) 297 { 298 char cmd[1024]; 299 char line[512]; 300 char xdisplay[512]; 301 static char proto[512], data[512]; 302 FILE *f; 303 int got_data = 0, generated = 0, do_unlink = 0, i; 304 char *xauthdir, *xauthfile; 305 struct stat st; 306 u_int now; 307 308 xauthdir = xauthfile = NULL; 309 *_proto = proto; 310 *_data = data; 311 proto[0] = data[0] = '\0'; 312 313 if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) { 314 debug("No xauth program."); 315 } else if (!client_x11_display_valid(display)) { 316 logit("DISPLAY '%s' invalid, falling back to fake xauth data", 317 display); 318 } else { 319 if (display == NULL) { 320 debug("x11_get_proto: DISPLAY not set"); 321 return; 322 } 323 /* 324 * Handle FamilyLocal case where $DISPLAY does 325 * not match an authorization entry. For this we 326 * just try "xauth list unix:displaynum.screennum". 327 * XXX: "localhost" match to determine FamilyLocal 328 * is not perfect. 329 */ 330 if (strncmp(display, "localhost:", 10) == 0) { 331 snprintf(xdisplay, sizeof(xdisplay), "unix:%s", 332 display + 10); 333 display = xdisplay; 334 } 335 if (trusted == 0) { 336 xauthdir = xmalloc(MAXPATHLEN); 337 xauthfile = xmalloc(MAXPATHLEN); 338 mktemp_proto(xauthdir, MAXPATHLEN); 339 if (mkdtemp(xauthdir) != NULL) { 340 do_unlink = 1; 341 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile", 342 xauthdir); 343 snprintf(cmd, sizeof(cmd), 344 "%s -f %s generate %s " SSH_X11_PROTO 345 " untrusted timeout %u 2>" _PATH_DEVNULL, 346 xauth_path, xauthfile, display, timeout); 347 debug2("x11_get_proto: %s", cmd); 348 if (system(cmd) == 0) 349 generated = 1; 350 if (x11_refuse_time == 0) { 351 now = time(NULL) + 1; 352 if (UINT_MAX - timeout < now) 353 x11_refuse_time = UINT_MAX; 354 else 355 x11_refuse_time = now + timeout; 356 } 357 } 358 } 359 360 /* 361 * When in untrusted mode, we read the cookie only if it was 362 * successfully generated as an untrusted one in the step 363 * above. 364 */ 365 if (trusted || generated) { 366 snprintf(cmd, sizeof(cmd), 367 "%s %s%s list %s 2>" _PATH_DEVNULL, 368 xauth_path, 369 generated ? "-f " : "" , 370 generated ? xauthfile : "", 371 display); 372 debug2("x11_get_proto: %s", cmd); 373 f = popen(cmd, "r"); 374 if (f && fgets(line, sizeof(line), f) && 375 sscanf(line, "%*s %511s %511s", proto, data) == 2) 376 got_data = 1; 377 if (f) 378 pclose(f); 379 } else 380 error("Warning: untrusted X11 forwarding setup failed: " 381 "xauth key data not generated"); 382 } 383 384 if (do_unlink) { 385 unlink(xauthfile); 386 rmdir(xauthdir); 387 } 388 if (xauthdir) 389 xfree(xauthdir); 390 if (xauthfile) 391 xfree(xauthfile); 392 393 /* 394 * If we didn't get authentication data, just make up some 395 * data. The forwarding code will check the validity of the 396 * response anyway, and substitute this data. The X11 397 * server, however, will ignore this fake data and use 398 * whatever authentication mechanisms it was using otherwise 399 * for the local connection. 400 */ 401 if (!got_data) { 402 u_int32_t rnd = 0; 403 404 logit("Warning: No xauth data; " 405 "using fake authentication data for X11 forwarding."); 406 strlcpy(proto, SSH_X11_PROTO, sizeof proto); 407 for (i = 0; i < 16; i++) { 408 if (i % 4 == 0) 409 rnd = arc4random(); 410 snprintf(data + 2 * i, sizeof data - 2 * i, "%02x", 411 rnd & 0xff); 412 rnd >>= 8; 413 } 414 } 415 } 416 417 /* 418 * This is called when the interactive is entered. This checks if there is 419 * an EOF coming on stdin. We must check this explicitly, as select() does 420 * not appear to wake up when redirecting from /dev/null. 421 */ 422 423 static void 424 client_check_initial_eof_on_stdin(void) 425 { 426 int len; 427 char buf[1]; 428 429 /* 430 * If standard input is to be "redirected from /dev/null", we simply 431 * mark that we have seen an EOF and send an EOF message to the 432 * server. Otherwise, we try to read a single character; it appears 433 * that for some files, such /dev/null, select() never wakes up for 434 * read for this descriptor, which means that we never get EOF. This 435 * way we will get the EOF if stdin comes from /dev/null or similar. 436 */ 437 if (stdin_null_flag) { 438 /* Fake EOF on stdin. */ 439 debug("Sending eof."); 440 stdin_eof = 1; 441 packet_start(SSH_CMSG_EOF); 442 packet_send(); 443 } else { 444 enter_non_blocking(); 445 446 /* Check for immediate EOF on stdin. */ 447 len = read(fileno(stdin), buf, 1); 448 if (len == 0) { 449 /* 450 * EOF. Record that we have seen it and send 451 * EOF to server. 452 */ 453 debug("Sending eof."); 454 stdin_eof = 1; 455 packet_start(SSH_CMSG_EOF); 456 packet_send(); 457 } else if (len > 0) { 458 /* 459 * Got data. We must store the data in the buffer, 460 * and also process it as an escape character if 461 * appropriate. 462 */ 463 if ((u_char) buf[0] == escape_char1) 464 escape_pending1 = 1; 465 else 466 buffer_append(&stdin_buffer, buf, 1); 467 } 468 leave_non_blocking(); 469 } 470 } 471 472 473 /* 474 * Make packets from buffered stdin data, and buffer them for sending to the 475 * connection. 476 */ 477 478 static void 479 client_make_packets_from_stdin_data(void) 480 { 481 u_int len; 482 483 /* Send buffered stdin data to the server. */ 484 while (buffer_len(&stdin_buffer) > 0 && 485 packet_not_very_much_data_to_write()) { 486 len = buffer_len(&stdin_buffer); 487 /* Keep the packets at reasonable size. */ 488 if (len > packet_get_maxsize()) 489 len = packet_get_maxsize(); 490 packet_start(SSH_CMSG_STDIN_DATA); 491 packet_put_string(buffer_ptr(&stdin_buffer), len); 492 packet_send(); 493 buffer_consume(&stdin_buffer, len); 494 /* If we have a pending EOF, send it now. */ 495 if (stdin_eof && buffer_len(&stdin_buffer) == 0) { 496 packet_start(SSH_CMSG_EOF); 497 packet_send(); 498 } 499 } 500 } 501 502 /* 503 * Checks if the client window has changed, and sends a packet about it to 504 * the server if so. The actual change is detected elsewhere (by a software 505 * interrupt on Unix); this just checks the flag and sends a message if 506 * appropriate. 507 */ 508 509 static void 510 client_check_window_change(void) 511 { 512 struct winsize ws; 513 514 if (! received_window_change_signal) 515 return; 516 /** XXX race */ 517 received_window_change_signal = 0; 518 519 debug2("client_check_window_change: changed"); 520 521 if (compat20) { 522 channel_send_window_changes(); 523 } else { 524 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) 525 return; 526 packet_start(SSH_CMSG_WINDOW_SIZE); 527 packet_put_int((u_int)ws.ws_row); 528 packet_put_int((u_int)ws.ws_col); 529 packet_put_int((u_int)ws.ws_xpixel); 530 packet_put_int((u_int)ws.ws_ypixel); 531 packet_send(); 532 } 533 } 534 535 static void 536 client_global_request_reply(int type, u_int32_t seq, void *ctxt) 537 { 538 struct global_confirm *gc; 539 540 if ((gc = TAILQ_FIRST(&global_confirms)) == NULL) 541 return; 542 if (gc->cb != NULL) 543 gc->cb(type, seq, gc->ctx); 544 if (--gc->ref_count <= 0) { 545 TAILQ_REMOVE(&global_confirms, gc, entry); 546 bzero(gc, sizeof(*gc)); 547 xfree(gc); 548 } 549 550 packet_set_alive_timeouts(0); 551 } 552 553 static void 554 server_alive_check(void) 555 { 556 if (packet_inc_alive_timeouts() > options.server_alive_count_max) { 557 logit("Timeout, server %s not responding.", host); 558 cleanup_exit(255); 559 } 560 packet_start(SSH2_MSG_GLOBAL_REQUEST); 561 packet_put_cstring("keepalive@openssh.com"); 562 packet_put_char(1); /* boolean: want reply */ 563 packet_send(); 564 /* Insert an empty placeholder to maintain ordering */ 565 client_register_global_confirm(NULL, NULL); 566 } 567 568 /* 569 * Waits until the client can do something (some data becomes available on 570 * one of the file descriptors). 571 */ 572 static void 573 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, 574 int *maxfdp, u_int *nallocp, int rekeying) 575 { 576 struct timeval tv, *tvp; 577 int timeout_secs; 578 time_t minwait_secs = 0; 579 int ret; 580 581 /* Add any selections by the channel mechanism. */ 582 channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 583 &minwait_secs, rekeying); 584 585 if (!compat20) { 586 /* Read from the connection, unless our buffers are full. */ 587 if (buffer_len(&stdout_buffer) < buffer_high && 588 buffer_len(&stderr_buffer) < buffer_high && 589 channel_not_very_much_buffered_data()) 590 FD_SET(connection_in, *readsetp); 591 /* 592 * Read from stdin, unless we have seen EOF or have very much 593 * buffered data to send to the server. 594 */ 595 if (!stdin_eof && packet_not_very_much_data_to_write()) 596 FD_SET(fileno(stdin), *readsetp); 597 598 /* Select stdout/stderr if have data in buffer. */ 599 if (buffer_len(&stdout_buffer) > 0) 600 FD_SET(fileno(stdout), *writesetp); 601 if (buffer_len(&stderr_buffer) > 0) 602 FD_SET(fileno(stderr), *writesetp); 603 } else { 604 /* channel_prepare_select could have closed the last channel */ 605 if (session_closed && !channel_still_open() && 606 !packet_have_data_to_write()) { 607 /* clear mask since we did not call select() */ 608 memset(*readsetp, 0, *nallocp); 609 memset(*writesetp, 0, *nallocp); 610 return; 611 } else { 612 FD_SET(connection_in, *readsetp); 613 } 614 } 615 616 /* Select server connection if have data to write to the server. */ 617 if (packet_have_data_to_write()) 618 FD_SET(connection_out, *writesetp); 619 620 /* 621 * Wait for something to happen. This will suspend the process until 622 * some selected descriptor can be read, written, or has some other 623 * event pending, or a timeout expires. 624 */ 625 626 timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */ 627 if (options.server_alive_interval > 0 && compat20) 628 timeout_secs = options.server_alive_interval; 629 set_control_persist_exit_time(); 630 if (control_persist_exit_time > 0) { 631 timeout_secs = MIN(timeout_secs, 632 control_persist_exit_time - time(NULL)); 633 if (timeout_secs < 0) 634 timeout_secs = 0; 635 } 636 if (minwait_secs != 0) 637 timeout_secs = MIN(timeout_secs, (int)minwait_secs); 638 if (timeout_secs == INT_MAX) 639 tvp = NULL; 640 else { 641 tv.tv_sec = timeout_secs; 642 tv.tv_usec = 0; 643 tvp = &tv; 644 } 645 646 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp); 647 if (ret < 0) { 648 char buf[100]; 649 650 /* 651 * We have to clear the select masks, because we return. 652 * We have to return, because the mainloop checks for the flags 653 * set by the signal handlers. 654 */ 655 memset(*readsetp, 0, *nallocp); 656 memset(*writesetp, 0, *nallocp); 657 658 if (errno == EINTR) 659 return; 660 /* Note: we might still have data in the buffers. */ 661 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno)); 662 buffer_append(&stderr_buffer, buf, strlen(buf)); 663 quit_pending = 1; 664 } else if (ret == 0) 665 server_alive_check(); 666 } 667 668 static void 669 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr) 670 { 671 /* Flush stdout and stderr buffers. */ 672 if (buffer_len(bout) > 0) 673 atomicio(vwrite, fileno(stdout), buffer_ptr(bout), 674 buffer_len(bout)); 675 if (buffer_len(berr) > 0) 676 atomicio(vwrite, fileno(stderr), buffer_ptr(berr), 677 buffer_len(berr)); 678 679 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 680 681 /* 682 * Free (and clear) the buffer to reduce the amount of data that gets 683 * written to swap. 684 */ 685 buffer_free(bin); 686 buffer_free(bout); 687 buffer_free(berr); 688 689 /* Send the suspend signal to the program itself. */ 690 kill(getpid(), SIGTSTP); 691 692 /* Reset window sizes in case they have changed */ 693 received_window_change_signal = 1; 694 695 /* OK, we have been continued by the user. Reinitialize buffers. */ 696 buffer_init(bin); 697 buffer_init(bout); 698 buffer_init(berr); 699 700 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 701 } 702 703 static void 704 client_process_net_input(fd_set *readset) 705 { 706 int len, cont = 0; 707 char buf[8192]; 708 709 /* 710 * Read input from the server, and add any such data to the buffer of 711 * the packet subsystem. 712 */ 713 if (FD_ISSET(connection_in, readset)) { 714 /* Read as much as possible. */ 715 len = roaming_read(connection_in, buf, sizeof(buf), &cont); 716 if (len == 0 && cont == 0) { 717 /* 718 * Received EOF. The remote host has closed the 719 * connection. 720 */ 721 snprintf(buf, sizeof buf, 722 "Connection to %.300s closed by remote host.\r\n", 723 host); 724 buffer_append(&stderr_buffer, buf, strlen(buf)); 725 quit_pending = 1; 726 return; 727 } 728 /* 729 * There is a kernel bug on Solaris that causes select to 730 * sometimes wake up even though there is no data available. 731 */ 732 if (len < 0 && (errno == EAGAIN || errno == EINTR)) 733 len = 0; 734 735 if (len < 0) { 736 /* 737 * An error has encountered. Perhaps there is a 738 * network problem. 739 */ 740 snprintf(buf, sizeof buf, 741 "Read from remote host %.300s: %.100s\r\n", 742 host, strerror(errno)); 743 buffer_append(&stderr_buffer, buf, strlen(buf)); 744 quit_pending = 1; 745 return; 746 } 747 packet_process_incoming(buf, len); 748 } 749 } 750 751 static void 752 client_status_confirm(int type, Channel *c, void *ctx) 753 { 754 struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx; 755 char errmsg[256]; 756 int tochan; 757 758 /* 759 * If a TTY was explicitly requested, then a failure to allocate 760 * one is fatal. 761 */ 762 if (cr->action == CONFIRM_TTY && 763 (options.request_tty == REQUEST_TTY_FORCE || 764 options.request_tty == REQUEST_TTY_YES)) 765 cr->action = CONFIRM_CLOSE; 766 767 /* XXX supress on mux _client_ quietmode */ 768 tochan = options.log_level >= SYSLOG_LEVEL_ERROR && 769 c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE; 770 771 if (type == SSH2_MSG_CHANNEL_SUCCESS) { 772 debug2("%s request accepted on channel %d", 773 cr->request_type, c->self); 774 } else if (type == SSH2_MSG_CHANNEL_FAILURE) { 775 if (tochan) { 776 snprintf(errmsg, sizeof(errmsg), 777 "%s request failed\r\n", cr->request_type); 778 } else { 779 snprintf(errmsg, sizeof(errmsg), 780 "%s request failed on channel %d", 781 cr->request_type, c->self); 782 } 783 /* If error occurred on primary session channel, then exit */ 784 if (cr->action == CONFIRM_CLOSE && c->self == session_ident) 785 fatal("%s", errmsg); 786 /* 787 * If error occurred on mux client, append to 788 * their stderr. 789 */ 790 if (tochan) { 791 buffer_append(&c->extended, errmsg, 792 strlen(errmsg)); 793 } else 794 error("%s", errmsg); 795 if (cr->action == CONFIRM_TTY) { 796 /* 797 * If a TTY allocation error occurred, then arrange 798 * for the correct TTY to leave raw mode. 799 */ 800 if (c->self == session_ident) 801 leave_raw_mode(0); 802 else 803 mux_tty_alloc_failed(c); 804 } else if (cr->action == CONFIRM_CLOSE) { 805 chan_read_failed(c); 806 chan_write_failed(c); 807 } 808 } 809 xfree(cr); 810 } 811 812 static void 813 client_abandon_status_confirm(Channel *c, void *ctx) 814 { 815 xfree(ctx); 816 } 817 818 void 819 client_expect_confirm(int id, const char *request, 820 enum confirm_action action) 821 { 822 struct channel_reply_ctx *cr = xmalloc(sizeof(*cr)); 823 824 cr->request_type = request; 825 cr->action = action; 826 827 channel_register_status_confirm(id, client_status_confirm, 828 client_abandon_status_confirm, cr); 829 } 830 831 void 832 client_register_global_confirm(global_confirm_cb *cb, void *ctx) 833 { 834 struct global_confirm *gc, *last_gc; 835 836 /* Coalesce identical callbacks */ 837 last_gc = TAILQ_LAST(&global_confirms, global_confirms); 838 if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) { 839 if (++last_gc->ref_count >= INT_MAX) 840 fatal("%s: last_gc->ref_count = %d", 841 __func__, last_gc->ref_count); 842 return; 843 } 844 845 gc = xmalloc(sizeof(*gc)); 846 gc->cb = cb; 847 gc->ctx = ctx; 848 gc->ref_count = 1; 849 TAILQ_INSERT_TAIL(&global_confirms, gc, entry); 850 } 851 852 static void 853 process_cmdline(void) 854 { 855 void (*handler)(int); 856 char *s, *cmd, *cancel_host; 857 int delete = 0, local = 0, remote = 0, dynamic = 0; 858 int cancel_port, ok; 859 Forward fwd; 860 861 bzero(&fwd, sizeof(fwd)); 862 fwd.listen_host = fwd.connect_host = NULL; 863 864 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 865 handler = signal(SIGINT, SIG_IGN); 866 cmd = s = read_passphrase("\r\nssh> ", RP_ECHO); 867 if (s == NULL) 868 goto out; 869 while (isspace(*s)) 870 s++; 871 if (*s == '-') 872 s++; /* Skip cmdline '-', if any */ 873 if (*s == '\0') 874 goto out; 875 876 if (*s == 'h' || *s == 'H' || *s == '?') { 877 logit("Commands:"); 878 logit(" -L[bind_address:]port:host:hostport " 879 "Request local forward"); 880 logit(" -R[bind_address:]port:host:hostport " 881 "Request remote forward"); 882 logit(" -D[bind_address:]port " 883 "Request dynamic forward"); 884 logit(" -KL[bind_address:]port " 885 "Cancel local forward"); 886 logit(" -KR[bind_address:]port " 887 "Cancel remote forward"); 888 logit(" -KD[bind_address:]port " 889 "Cancel dynamic forward"); 890 if (!options.permit_local_command) 891 goto out; 892 logit(" !args " 893 "Execute local command"); 894 goto out; 895 } 896 897 if (*s == '!' && options.permit_local_command) { 898 s++; 899 ssh_local_cmd(s); 900 goto out; 901 } 902 903 if (*s == 'K') { 904 delete = 1; 905 s++; 906 } 907 if (*s == 'L') 908 local = 1; 909 else if (*s == 'R') 910 remote = 1; 911 else if (*s == 'D') 912 dynamic = 1; 913 else { 914 logit("Invalid command."); 915 goto out; 916 } 917 918 if (delete && !compat20) { 919 logit("Not supported for SSH protocol version 1."); 920 goto out; 921 } 922 923 while (isspace(*++s)) 924 ; 925 926 /* XXX update list of forwards in options */ 927 if (delete) { 928 cancel_port = 0; 929 cancel_host = hpdelim(&s); /* may be NULL */ 930 if (s != NULL) { 931 cancel_port = a2port(s); 932 cancel_host = cleanhostname(cancel_host); 933 } else { 934 cancel_port = a2port(cancel_host); 935 cancel_host = NULL; 936 } 937 if (cancel_port <= 0) { 938 logit("Bad forwarding close port"); 939 goto out; 940 } 941 if (remote) 942 ok = channel_request_rforward_cancel(cancel_host, 943 cancel_port) == 0; 944 else if (dynamic) 945 ok = channel_cancel_lport_listener(cancel_host, 946 cancel_port, 0, options.gateway_ports) > 0; 947 else 948 ok = channel_cancel_lport_listener(cancel_host, 949 cancel_port, CHANNEL_CANCEL_PORT_STATIC, 950 options.gateway_ports) > 0; 951 if (!ok) { 952 logit("Unkown port forwarding."); 953 goto out; 954 } 955 logit("Canceled forwarding."); 956 } else { 957 if (!parse_forward(&fwd, s, dynamic, remote)) { 958 logit("Bad forwarding specification."); 959 goto out; 960 } 961 if (local || dynamic) { 962 if (!channel_setup_local_fwd_listener(fwd.listen_host, 963 fwd.listen_port, fwd.connect_host, 964 fwd.connect_port, options.gateway_ports)) { 965 logit("Port forwarding failed."); 966 goto out; 967 } 968 } else { 969 if (channel_request_remote_forwarding(fwd.listen_host, 970 fwd.listen_port, fwd.connect_host, 971 fwd.connect_port) < 0) { 972 logit("Port forwarding failed."); 973 goto out; 974 } 975 } 976 logit("Forwarding port."); 977 } 978 979 out: 980 signal(SIGINT, handler); 981 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 982 if (cmd) 983 xfree(cmd); 984 if (fwd.listen_host != NULL) 985 xfree(fwd.listen_host); 986 if (fwd.connect_host != NULL) 987 xfree(fwd.connect_host); 988 } 989 990 /* reasons to suppress output of an escape command in help output */ 991 #define SUPPRESS_NEVER 0 /* never suppress, always show */ 992 #define SUPPRESS_PROTO1 1 /* don't show in protocol 1 sessions */ 993 #define SUPPRESS_MUXCLIENT 2 /* don't show in mux client sessions */ 994 #define SUPPRESS_MUXMASTER 4 /* don't show in mux master sessions */ 995 #define SUPPRESS_SYSLOG 8 /* don't show when logging to syslog */ 996 struct escape_help_text { 997 const char *cmd; 998 const char *text; 999 unsigned int flags; 1000 }; 1001 static struct escape_help_text esc_txt[] = { 1002 {".", "terminate session", SUPPRESS_MUXMASTER}, 1003 {".", "terminate connection (and any multiplexed sessions)", 1004 SUPPRESS_MUXCLIENT}, 1005 {"B", "send a BREAK to the remote system", SUPPRESS_PROTO1}, 1006 {"C", "open a command line", SUPPRESS_MUXCLIENT}, 1007 {"R", "request rekey", SUPPRESS_PROTO1}, 1008 {"V/v", "decrease/increase verbosity (LogLevel)", SUPPRESS_MUXCLIENT}, 1009 {"^Z", "suspend ssh", SUPPRESS_MUXCLIENT}, 1010 {"#", "list forwarded connections", SUPPRESS_NEVER}, 1011 {"&", "background ssh (when waiting for connections to terminate)", 1012 SUPPRESS_MUXCLIENT}, 1013 {"?", "this message", SUPPRESS_NEVER}, 1014 }; 1015 1016 static void 1017 print_escape_help(Buffer *b, int escape_char, int protocol2, int mux_client, 1018 int using_stderr) 1019 { 1020 unsigned int i, suppress_flags; 1021 char string[1024]; 1022 1023 snprintf(string, sizeof string, "%c?\r\n" 1024 "Supported escape sequences:\r\n", escape_char); 1025 buffer_append(b, string, strlen(string)); 1026 1027 suppress_flags = (protocol2 ? 0 : SUPPRESS_PROTO1) | 1028 (mux_client ? SUPPRESS_MUXCLIENT : 0) | 1029 (mux_client ? 0 : SUPPRESS_MUXMASTER) | 1030 (using_stderr ? 0 : SUPPRESS_SYSLOG); 1031 1032 for (i = 0; i < sizeof(esc_txt)/sizeof(esc_txt[0]); i++) { 1033 if (esc_txt[i].flags & suppress_flags) 1034 continue; 1035 snprintf(string, sizeof string, " %c%-3s - %s\r\n", 1036 escape_char, esc_txt[i].cmd, esc_txt[i].text); 1037 buffer_append(b, string, strlen(string)); 1038 } 1039 1040 snprintf(string, sizeof string, 1041 " %c%c - send the escape character by typing it twice\r\n" 1042 "(Note that escapes are only recognized immediately after " 1043 "newline.)\r\n", escape_char, escape_char); 1044 buffer_append(b, string, strlen(string)); 1045 } 1046 1047 /* 1048 * Process the characters one by one, call with c==NULL for proto1 case. 1049 */ 1050 static int 1051 process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr, 1052 char *buf, int len) 1053 { 1054 char string[1024]; 1055 pid_t pid; 1056 int bytes = 0; 1057 u_int i; 1058 u_char ch; 1059 char *s; 1060 int *escape_pendingp, escape_char; 1061 struct escape_filter_ctx *efc; 1062 1063 if (c == NULL) { 1064 escape_pendingp = &escape_pending1; 1065 escape_char = escape_char1; 1066 } else { 1067 if (c->filter_ctx == NULL) 1068 return 0; 1069 efc = (struct escape_filter_ctx *)c->filter_ctx; 1070 escape_pendingp = &efc->escape_pending; 1071 escape_char = efc->escape_char; 1072 } 1073 1074 if (len <= 0) 1075 return (0); 1076 1077 for (i = 0; i < (u_int)len; i++) { 1078 /* Get one character at a time. */ 1079 ch = buf[i]; 1080 1081 if (*escape_pendingp) { 1082 /* We have previously seen an escape character. */ 1083 /* Clear the flag now. */ 1084 *escape_pendingp = 0; 1085 1086 /* Process the escaped character. */ 1087 switch (ch) { 1088 case '.': 1089 /* Terminate the connection. */ 1090 snprintf(string, sizeof string, "%c.\r\n", 1091 escape_char); 1092 buffer_append(berr, string, strlen(string)); 1093 1094 if (c && c->ctl_chan != -1) { 1095 chan_read_failed(c); 1096 chan_write_failed(c); 1097 mux_master_session_cleanup_cb(c->self, 1098 NULL); 1099 return 0; 1100 } else 1101 quit_pending = 1; 1102 return -1; 1103 1104 case 'Z' - 64: 1105 /* XXX support this for mux clients */ 1106 if (c && c->ctl_chan != -1) { 1107 char b[16]; 1108 noescape: 1109 if (ch == 'Z' - 64) 1110 snprintf(b, sizeof b, "^Z"); 1111 else 1112 snprintf(b, sizeof b, "%c", ch); 1113 snprintf(string, sizeof string, 1114 "%c%s escape not available to " 1115 "multiplexed sessions\r\n", 1116 escape_char, b); 1117 buffer_append(berr, string, 1118 strlen(string)); 1119 continue; 1120 } 1121 /* Suspend the program. Inform the user */ 1122 snprintf(string, sizeof string, 1123 "%c^Z [suspend ssh]\r\n", escape_char); 1124 buffer_append(berr, string, strlen(string)); 1125 1126 /* Restore terminal modes and suspend. */ 1127 client_suspend_self(bin, bout, berr); 1128 1129 /* We have been continued. */ 1130 continue; 1131 1132 case 'B': 1133 if (compat20) { 1134 snprintf(string, sizeof string, 1135 "%cB\r\n", escape_char); 1136 buffer_append(berr, string, 1137 strlen(string)); 1138 channel_request_start(session_ident, 1139 "break", 0); 1140 packet_put_int(1000); 1141 packet_send(); 1142 } 1143 continue; 1144 1145 case 'R': 1146 if (compat20) { 1147 if (datafellows & SSH_BUG_NOREKEY) 1148 logit("Server does not " 1149 "support re-keying"); 1150 else 1151 need_rekeying = 1; 1152 } 1153 continue; 1154 1155 case 'V': 1156 /* FALLTHROUGH */ 1157 case 'v': 1158 if (c && c->ctl_chan != -1) 1159 goto noescape; 1160 if (!log_is_on_stderr()) { 1161 snprintf(string, sizeof string, 1162 "%c%c [Logging to syslog]\r\n", 1163 escape_char, ch); 1164 buffer_append(berr, string, 1165 strlen(string)); 1166 continue; 1167 } 1168 if (ch == 'V' && options.log_level > 1169 SYSLOG_LEVEL_QUIET) 1170 log_change_level(--options.log_level); 1171 if (ch == 'v' && options.log_level < 1172 SYSLOG_LEVEL_DEBUG3) 1173 log_change_level(++options.log_level); 1174 snprintf(string, sizeof string, 1175 "%c%c [LogLevel %s]\r\n", escape_char, ch, 1176 log_level_name(options.log_level)); 1177 buffer_append(berr, string, strlen(string)); 1178 continue; 1179 1180 case '&': 1181 if (c && c->ctl_chan != -1) 1182 goto noescape; 1183 /* 1184 * Detach the program (continue to serve 1185 * connections, but put in background and no 1186 * more new connections). 1187 */ 1188 /* Restore tty modes. */ 1189 leave_raw_mode( 1190 options.request_tty == REQUEST_TTY_FORCE); 1191 1192 /* Stop listening for new connections. */ 1193 channel_stop_listening(); 1194 1195 snprintf(string, sizeof string, 1196 "%c& [backgrounded]\n", escape_char); 1197 buffer_append(berr, string, strlen(string)); 1198 1199 /* Fork into background. */ 1200 pid = fork(); 1201 if (pid < 0) { 1202 error("fork: %.100s", strerror(errno)); 1203 continue; 1204 } 1205 if (pid != 0) { /* This is the parent. */ 1206 /* The parent just exits. */ 1207 exit(0); 1208 } 1209 /* The child continues serving connections. */ 1210 if (compat20) { 1211 buffer_append(bin, "\004", 1); 1212 /* fake EOF on stdin */ 1213 return -1; 1214 } else if (!stdin_eof) { 1215 /* 1216 * Sending SSH_CMSG_EOF alone does not 1217 * always appear to be enough. So we 1218 * try to send an EOF character first. 1219 */ 1220 packet_start(SSH_CMSG_STDIN_DATA); 1221 packet_put_string("\004", 1); 1222 packet_send(); 1223 /* Close stdin. */ 1224 stdin_eof = 1; 1225 if (buffer_len(bin) == 0) { 1226 packet_start(SSH_CMSG_EOF); 1227 packet_send(); 1228 } 1229 } 1230 continue; 1231 1232 case '?': 1233 print_escape_help(berr, escape_char, compat20, 1234 (c && c->ctl_chan != -1), 1235 log_is_on_stderr()); 1236 continue; 1237 1238 case '#': 1239 snprintf(string, sizeof string, "%c#\r\n", 1240 escape_char); 1241 buffer_append(berr, string, strlen(string)); 1242 s = channel_open_message(); 1243 buffer_append(berr, s, strlen(s)); 1244 xfree(s); 1245 continue; 1246 1247 case 'C': 1248 if (c && c->ctl_chan != -1) 1249 goto noescape; 1250 process_cmdline(); 1251 continue; 1252 1253 default: 1254 if (ch != escape_char) { 1255 buffer_put_char(bin, escape_char); 1256 bytes++; 1257 } 1258 /* Escaped characters fall through here */ 1259 break; 1260 } 1261 } else { 1262 /* 1263 * The previous character was not an escape char. 1264 * Check if this is an escape. 1265 */ 1266 if (last_was_cr && ch == escape_char) { 1267 /* 1268 * It is. Set the flag and continue to 1269 * next character. 1270 */ 1271 *escape_pendingp = 1; 1272 continue; 1273 } 1274 } 1275 1276 /* 1277 * Normal character. Record whether it was a newline, 1278 * and append it to the buffer. 1279 */ 1280 last_was_cr = (ch == '\r' || ch == '\n'); 1281 buffer_put_char(bin, ch); 1282 bytes++; 1283 } 1284 return bytes; 1285 } 1286 1287 static void 1288 client_process_input(fd_set *readset) 1289 { 1290 int len; 1291 char buf[8192]; 1292 1293 /* Read input from stdin. */ 1294 if (FD_ISSET(fileno(stdin), readset)) { 1295 /* Read as much as possible. */ 1296 len = read(fileno(stdin), buf, sizeof(buf)); 1297 if (len < 0 && (errno == EAGAIN || errno == EINTR)) 1298 return; /* we'll try again later */ 1299 if (len <= 0) { 1300 /* 1301 * Received EOF or error. They are treated 1302 * similarly, except that an error message is printed 1303 * if it was an error condition. 1304 */ 1305 if (len < 0) { 1306 snprintf(buf, sizeof buf, "read: %.100s\r\n", 1307 strerror(errno)); 1308 buffer_append(&stderr_buffer, buf, strlen(buf)); 1309 } 1310 /* Mark that we have seen EOF. */ 1311 stdin_eof = 1; 1312 /* 1313 * Send an EOF message to the server unless there is 1314 * data in the buffer. If there is data in the 1315 * buffer, no message will be sent now. Code 1316 * elsewhere will send the EOF when the buffer 1317 * becomes empty if stdin_eof is set. 1318 */ 1319 if (buffer_len(&stdin_buffer) == 0) { 1320 packet_start(SSH_CMSG_EOF); 1321 packet_send(); 1322 } 1323 } else if (escape_char1 == SSH_ESCAPECHAR_NONE) { 1324 /* 1325 * Normal successful read, and no escape character. 1326 * Just append the data to buffer. 1327 */ 1328 buffer_append(&stdin_buffer, buf, len); 1329 } else { 1330 /* 1331 * Normal, successful read. But we have an escape 1332 * character and have to process the characters one 1333 * by one. 1334 */ 1335 if (process_escapes(NULL, &stdin_buffer, 1336 &stdout_buffer, &stderr_buffer, buf, len) == -1) 1337 return; 1338 } 1339 } 1340 } 1341 1342 static void 1343 client_process_output(fd_set *writeset) 1344 { 1345 int len; 1346 char buf[100]; 1347 1348 /* Write buffered output to stdout. */ 1349 if (FD_ISSET(fileno(stdout), writeset)) { 1350 /* Write as much data as possible. */ 1351 len = write(fileno(stdout), buffer_ptr(&stdout_buffer), 1352 buffer_len(&stdout_buffer)); 1353 if (len <= 0) { 1354 if (errno == EINTR || errno == EAGAIN) 1355 len = 0; 1356 else { 1357 /* 1358 * An error or EOF was encountered. Put an 1359 * error message to stderr buffer. 1360 */ 1361 snprintf(buf, sizeof buf, 1362 "write stdout: %.50s\r\n", strerror(errno)); 1363 buffer_append(&stderr_buffer, buf, strlen(buf)); 1364 quit_pending = 1; 1365 return; 1366 } 1367 } 1368 /* Consume printed data from the buffer. */ 1369 buffer_consume(&stdout_buffer, len); 1370 } 1371 /* Write buffered output to stderr. */ 1372 if (FD_ISSET(fileno(stderr), writeset)) { 1373 /* Write as much data as possible. */ 1374 len = write(fileno(stderr), buffer_ptr(&stderr_buffer), 1375 buffer_len(&stderr_buffer)); 1376 if (len <= 0) { 1377 if (errno == EINTR || errno == EAGAIN) 1378 len = 0; 1379 else { 1380 /* 1381 * EOF or error, but can't even print 1382 * error message. 1383 */ 1384 quit_pending = 1; 1385 return; 1386 } 1387 } 1388 /* Consume printed characters from the buffer. */ 1389 buffer_consume(&stderr_buffer, len); 1390 } 1391 } 1392 1393 /* 1394 * Get packets from the connection input buffer, and process them as long as 1395 * there are packets available. 1396 * 1397 * Any unknown packets received during the actual 1398 * session cause the session to terminate. This is 1399 * intended to make debugging easier since no 1400 * confirmations are sent. Any compatible protocol 1401 * extensions must be negotiated during the 1402 * preparatory phase. 1403 */ 1404 1405 static void 1406 client_process_buffered_input_packets(void) 1407 { 1408 dispatch_run(DISPATCH_NONBLOCK, &quit_pending, 1409 compat20 ? xxx_kex : NULL); 1410 } 1411 1412 /* scan buf[] for '~' before sending data to the peer */ 1413 1414 /* Helper: allocate a new escape_filter_ctx and fill in its escape char */ 1415 void * 1416 client_new_escape_filter_ctx(int escape_char) 1417 { 1418 struct escape_filter_ctx *ret; 1419 1420 ret = xmalloc(sizeof(*ret)); 1421 ret->escape_pending = 0; 1422 ret->escape_char = escape_char; 1423 return (void *)ret; 1424 } 1425 1426 /* Free the escape filter context on channel free */ 1427 void 1428 client_filter_cleanup(int cid, void *ctx) 1429 { 1430 xfree(ctx); 1431 } 1432 1433 int 1434 client_simple_escape_filter(Channel *c, char *buf, int len) 1435 { 1436 if (c->extended_usage != CHAN_EXTENDED_WRITE) 1437 return 0; 1438 1439 return process_escapes(c, &c->input, &c->output, &c->extended, 1440 buf, len); 1441 } 1442 1443 static void 1444 client_channel_closed(int id, void *arg) 1445 { 1446 channel_cancel_cleanup(id); 1447 session_closed = 1; 1448 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 1449 } 1450 1451 /* 1452 * Implements the interactive session with the server. This is called after 1453 * the user has been authenticated, and a command has been started on the 1454 * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character 1455 * used as an escape character for terminating or suspending the session. 1456 */ 1457 1458 int 1459 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id) 1460 { 1461 fd_set *readset = NULL, *writeset = NULL; 1462 double start_time, total_time; 1463 int max_fd = 0, max_fd2 = 0, len, rekeying = 0; 1464 u_int64_t ibytes, obytes; 1465 u_int nalloc = 0; 1466 char buf[100]; 1467 1468 debug("Entering interactive session."); 1469 1470 start_time = get_current_time(); 1471 1472 /* Initialize variables. */ 1473 escape_pending1 = 0; 1474 last_was_cr = 1; 1475 exit_status = -1; 1476 stdin_eof = 0; 1477 buffer_high = 64 * 1024; 1478 connection_in = packet_get_connection_in(); 1479 connection_out = packet_get_connection_out(); 1480 max_fd = MAX(connection_in, connection_out); 1481 1482 if (!compat20) { 1483 /* enable nonblocking unless tty */ 1484 if (!isatty(fileno(stdin))) 1485 set_nonblock(fileno(stdin)); 1486 if (!isatty(fileno(stdout))) 1487 set_nonblock(fileno(stdout)); 1488 if (!isatty(fileno(stderr))) 1489 set_nonblock(fileno(stderr)); 1490 max_fd = MAX(max_fd, fileno(stdin)); 1491 max_fd = MAX(max_fd, fileno(stdout)); 1492 max_fd = MAX(max_fd, fileno(stderr)); 1493 } 1494 quit_pending = 0; 1495 escape_char1 = escape_char_arg; 1496 1497 /* Initialize buffers. */ 1498 buffer_init(&stdin_buffer); 1499 buffer_init(&stdout_buffer); 1500 buffer_init(&stderr_buffer); 1501 1502 client_init_dispatch(); 1503 1504 /* 1505 * Set signal handlers, (e.g. to restore non-blocking mode) 1506 * but don't overwrite SIG_IGN, matches behaviour from rsh(1) 1507 */ 1508 if (signal(SIGHUP, SIG_IGN) != SIG_IGN) 1509 signal(SIGHUP, signal_handler); 1510 if (signal(SIGINT, SIG_IGN) != SIG_IGN) 1511 signal(SIGINT, signal_handler); 1512 if (signal(SIGQUIT, SIG_IGN) != SIG_IGN) 1513 signal(SIGQUIT, signal_handler); 1514 if (signal(SIGTERM, SIG_IGN) != SIG_IGN) 1515 signal(SIGTERM, signal_handler); 1516 signal(SIGWINCH, window_change_handler); 1517 1518 if (have_pty) 1519 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 1520 1521 if (compat20) { 1522 session_ident = ssh2_chan_id; 1523 if (session_ident != -1) { 1524 if (escape_char_arg != SSH_ESCAPECHAR_NONE) { 1525 channel_register_filter(session_ident, 1526 client_simple_escape_filter, NULL, 1527 client_filter_cleanup, 1528 client_new_escape_filter_ctx( 1529 escape_char_arg)); 1530 } 1531 channel_register_cleanup(session_ident, 1532 client_channel_closed, 0); 1533 } 1534 } else { 1535 /* Check if we should immediately send eof on stdin. */ 1536 client_check_initial_eof_on_stdin(); 1537 } 1538 1539 /* Main loop of the client for the interactive session mode. */ 1540 while (!quit_pending) { 1541 1542 /* Process buffered packets sent by the server. */ 1543 client_process_buffered_input_packets(); 1544 1545 if (compat20 && session_closed && !channel_still_open()) 1546 break; 1547 1548 rekeying = (xxx_kex != NULL && !xxx_kex->done); 1549 1550 if (rekeying) { 1551 debug("rekeying in progress"); 1552 } else { 1553 /* 1554 * Make packets of buffered stdin data, and buffer 1555 * them for sending to the server. 1556 */ 1557 if (!compat20) 1558 client_make_packets_from_stdin_data(); 1559 1560 /* 1561 * Make packets from buffered channel data, and 1562 * enqueue them for sending to the server. 1563 */ 1564 if (packet_not_very_much_data_to_write()) 1565 channel_output_poll(); 1566 1567 /* 1568 * Check if the window size has changed, and buffer a 1569 * message about it to the server if so. 1570 */ 1571 client_check_window_change(); 1572 1573 if (quit_pending) 1574 break; 1575 } 1576 /* 1577 * Wait until we have something to do (something becomes 1578 * available on one of the descriptors). 1579 */ 1580 max_fd2 = max_fd; 1581 client_wait_until_can_do_something(&readset, &writeset, 1582 &max_fd2, &nalloc, rekeying); 1583 1584 if (quit_pending) 1585 break; 1586 1587 /* Do channel operations unless rekeying in progress. */ 1588 if (!rekeying) { 1589 channel_after_select(readset, writeset); 1590 if (need_rekeying || packet_need_rekeying()) { 1591 debug("need rekeying"); 1592 xxx_kex->done = 0; 1593 kex_send_kexinit(xxx_kex); 1594 need_rekeying = 0; 1595 } 1596 } 1597 1598 /* Buffer input from the connection. */ 1599 client_process_net_input(readset); 1600 1601 if (quit_pending) 1602 break; 1603 1604 if (!compat20) { 1605 /* Buffer data from stdin */ 1606 client_process_input(readset); 1607 /* 1608 * Process output to stdout and stderr. Output to 1609 * the connection is processed elsewhere (above). 1610 */ 1611 client_process_output(writeset); 1612 } 1613 1614 if (session_resumed) { 1615 connection_in = packet_get_connection_in(); 1616 connection_out = packet_get_connection_out(); 1617 max_fd = MAX(max_fd, connection_out); 1618 max_fd = MAX(max_fd, connection_in); 1619 session_resumed = 0; 1620 } 1621 1622 /* 1623 * Send as much buffered packet data as possible to the 1624 * sender. 1625 */ 1626 if (FD_ISSET(connection_out, writeset)) 1627 packet_write_poll(); 1628 1629 /* 1630 * If we are a backgrounded control master, and the 1631 * timeout has expired without any active client 1632 * connections, then quit. 1633 */ 1634 if (control_persist_exit_time > 0) { 1635 if (time(NULL) >= control_persist_exit_time) { 1636 debug("ControlPersist timeout expired"); 1637 break; 1638 } 1639 } 1640 } 1641 if (readset) 1642 xfree(readset); 1643 if (writeset) 1644 xfree(writeset); 1645 1646 /* Terminate the session. */ 1647 1648 /* Stop watching for window change. */ 1649 signal(SIGWINCH, SIG_DFL); 1650 1651 if (compat20) { 1652 packet_start(SSH2_MSG_DISCONNECT); 1653 packet_put_int(SSH2_DISCONNECT_BY_APPLICATION); 1654 packet_put_cstring("disconnected by user"); 1655 packet_put_cstring(""); /* language tag */ 1656 packet_send(); 1657 packet_write_wait(); 1658 } 1659 1660 channel_free_all(); 1661 1662 if (have_pty) 1663 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 1664 1665 /* restore blocking io */ 1666 if (!isatty(fileno(stdin))) 1667 unset_nonblock(fileno(stdin)); 1668 if (!isatty(fileno(stdout))) 1669 unset_nonblock(fileno(stdout)); 1670 if (!isatty(fileno(stderr))) 1671 unset_nonblock(fileno(stderr)); 1672 1673 /* 1674 * If there was no shell or command requested, there will be no remote 1675 * exit status to be returned. In that case, clear error code if the 1676 * connection was deliberately terminated at this end. 1677 */ 1678 if (no_shell_flag && received_signal == SIGTERM) { 1679 received_signal = 0; 1680 exit_status = 0; 1681 } 1682 1683 if (received_signal) 1684 fatal("Killed by signal %d.", (int) received_signal); 1685 1686 /* 1687 * In interactive mode (with pseudo tty) display a message indicating 1688 * that the connection has been closed. 1689 */ 1690 if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) { 1691 snprintf(buf, sizeof buf, 1692 "Connection to %.64s closed.\r\n", host); 1693 buffer_append(&stderr_buffer, buf, strlen(buf)); 1694 } 1695 1696 /* Output any buffered data for stdout. */ 1697 if (buffer_len(&stdout_buffer) > 0) { 1698 len = atomicio(vwrite, fileno(stdout), 1699 buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer)); 1700 if (len < 0 || (u_int)len != buffer_len(&stdout_buffer)) 1701 error("Write failed flushing stdout buffer."); 1702 else 1703 buffer_consume(&stdout_buffer, len); 1704 } 1705 1706 /* Output any buffered data for stderr. */ 1707 if (buffer_len(&stderr_buffer) > 0) { 1708 len = atomicio(vwrite, fileno(stderr), 1709 buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer)); 1710 if (len < 0 || (u_int)len != buffer_len(&stderr_buffer)) 1711 error("Write failed flushing stderr buffer."); 1712 else 1713 buffer_consume(&stderr_buffer, len); 1714 } 1715 1716 /* Clear and free any buffers. */ 1717 memset(buf, 0, sizeof(buf)); 1718 buffer_free(&stdin_buffer); 1719 buffer_free(&stdout_buffer); 1720 buffer_free(&stderr_buffer); 1721 1722 /* Report bytes transferred, and transfer rates. */ 1723 total_time = get_current_time() - start_time; 1724 packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes); 1725 packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes); 1726 verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds", 1727 (unsigned long long)obytes, (unsigned long long)ibytes, total_time); 1728 if (total_time > 0) 1729 verbose("Bytes per second: sent %.1f, received %.1f", 1730 obytes / total_time, ibytes / total_time); 1731 /* Return the exit status of the program. */ 1732 debug("Exit status %d", exit_status); 1733 return exit_status; 1734 } 1735 1736 /*********/ 1737 1738 static void 1739 client_input_stdout_data(int type, u_int32_t seq, void *ctxt) 1740 { 1741 u_int data_len; 1742 char *data = packet_get_string(&data_len); 1743 packet_check_eom(); 1744 buffer_append(&stdout_buffer, data, data_len); 1745 memset(data, 0, data_len); 1746 xfree(data); 1747 } 1748 static void 1749 client_input_stderr_data(int type, u_int32_t seq, void *ctxt) 1750 { 1751 u_int data_len; 1752 char *data = packet_get_string(&data_len); 1753 packet_check_eom(); 1754 buffer_append(&stderr_buffer, data, data_len); 1755 memset(data, 0, data_len); 1756 xfree(data); 1757 } 1758 static void 1759 client_input_exit_status(int type, u_int32_t seq, void *ctxt) 1760 { 1761 exit_status = packet_get_int(); 1762 packet_check_eom(); 1763 /* Acknowledge the exit. */ 1764 packet_start(SSH_CMSG_EXIT_CONFIRMATION); 1765 packet_send(); 1766 /* 1767 * Must wait for packet to be sent since we are 1768 * exiting the loop. 1769 */ 1770 packet_write_wait(); 1771 /* Flag that we want to exit. */ 1772 quit_pending = 1; 1773 } 1774 static void 1775 client_input_agent_open(int type, u_int32_t seq, void *ctxt) 1776 { 1777 Channel *c = NULL; 1778 int remote_id, sock; 1779 1780 /* Read the remote channel number from the message. */ 1781 remote_id = packet_get_int(); 1782 packet_check_eom(); 1783 1784 /* 1785 * Get a connection to the local authentication agent (this may again 1786 * get forwarded). 1787 */ 1788 sock = ssh_get_authentication_socket(); 1789 1790 /* 1791 * If we could not connect the agent, send an error message back to 1792 * the server. This should never happen unless the agent dies, 1793 * because authentication forwarding is only enabled if we have an 1794 * agent. 1795 */ 1796 if (sock >= 0) { 1797 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, 1798 -1, 0, 0, 0, "authentication agent connection", 1); 1799 c->remote_id = remote_id; 1800 c->force_drain = 1; 1801 } 1802 if (c == NULL) { 1803 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); 1804 packet_put_int(remote_id); 1805 } else { 1806 /* Send a confirmation to the remote host. */ 1807 debug("Forwarding authentication connection."); 1808 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); 1809 packet_put_int(remote_id); 1810 packet_put_int(c->self); 1811 } 1812 packet_send(); 1813 } 1814 1815 static Channel * 1816 client_request_forwarded_tcpip(const char *request_type, int rchan) 1817 { 1818 Channel *c = NULL; 1819 char *listen_address, *originator_address; 1820 u_short listen_port, originator_port; 1821 1822 /* Get rest of the packet */ 1823 listen_address = packet_get_string(NULL); 1824 listen_port = packet_get_int(); 1825 originator_address = packet_get_string(NULL); 1826 originator_port = packet_get_int(); 1827 packet_check_eom(); 1828 1829 debug("client_request_forwarded_tcpip: listen %s port %d, " 1830 "originator %s port %d", listen_address, listen_port, 1831 originator_address, originator_port); 1832 1833 c = channel_connect_by_listen_address(listen_port, 1834 "forwarded-tcpip", originator_address); 1835 1836 xfree(originator_address); 1837 xfree(listen_address); 1838 return c; 1839 } 1840 1841 static Channel * 1842 client_request_x11(const char *request_type, int rchan) 1843 { 1844 Channel *c = NULL; 1845 char *originator; 1846 u_short originator_port; 1847 int sock; 1848 1849 if (!options.forward_x11) { 1850 error("Warning: ssh server tried X11 forwarding."); 1851 error("Warning: this is probably a break-in attempt by a " 1852 "malicious server."); 1853 return NULL; 1854 } 1855 if (x11_refuse_time != 0 && time(NULL) >= x11_refuse_time) { 1856 verbose("Rejected X11 connection after ForwardX11Timeout " 1857 "expired"); 1858 return NULL; 1859 } 1860 originator = packet_get_string(NULL); 1861 if (datafellows & SSH_BUG_X11FWD) { 1862 debug2("buggy server: x11 request w/o originator_port"); 1863 originator_port = 0; 1864 } else { 1865 originator_port = packet_get_int(); 1866 } 1867 packet_check_eom(); 1868 /* XXX check permission */ 1869 debug("client_request_x11: request from %s %d", originator, 1870 originator_port); 1871 xfree(originator); 1872 sock = x11_connect_display(); 1873 if (sock < 0) 1874 return NULL; 1875 c = channel_new("x11", 1876 SSH_CHANNEL_X11_OPEN, sock, sock, -1, 1877 CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1); 1878 c->force_drain = 1; 1879 return c; 1880 } 1881 1882 static Channel * 1883 client_request_agent(const char *request_type, int rchan) 1884 { 1885 Channel *c = NULL; 1886 int sock; 1887 1888 if (!options.forward_agent) { 1889 error("Warning: ssh server tried agent forwarding."); 1890 error("Warning: this is probably a break-in attempt by a " 1891 "malicious server."); 1892 return NULL; 1893 } 1894 sock = ssh_get_authentication_socket(); 1895 if (sock < 0) 1896 return NULL; 1897 c = channel_new("authentication agent connection", 1898 SSH_CHANNEL_OPEN, sock, sock, -1, 1899 CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, 1900 "authentication agent connection", 1); 1901 c->force_drain = 1; 1902 return c; 1903 } 1904 1905 int 1906 client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun) 1907 { 1908 Channel *c; 1909 int fd; 1910 1911 if (tun_mode == SSH_TUNMODE_NO) 1912 return 0; 1913 1914 if (!compat20) { 1915 error("Tunnel forwarding is not supported for protocol 1"); 1916 return -1; 1917 } 1918 1919 debug("Requesting tun unit %d in mode %d", local_tun, tun_mode); 1920 1921 /* Open local tunnel device */ 1922 if ((fd = tun_open(local_tun, tun_mode)) == -1) { 1923 error("Tunnel device open failed."); 1924 return -1; 1925 } 1926 1927 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1, 1928 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1); 1929 c->datagram = 1; 1930 1931 packet_start(SSH2_MSG_CHANNEL_OPEN); 1932 packet_put_cstring("tun@openssh.com"); 1933 packet_put_int(c->self); 1934 packet_put_int(c->local_window_max); 1935 packet_put_int(c->local_maxpacket); 1936 packet_put_int(tun_mode); 1937 packet_put_int(remote_tun); 1938 packet_send(); 1939 1940 return 0; 1941 } 1942 1943 /* XXXX move to generic input handler */ 1944 static void 1945 client_input_channel_open(int type, u_int32_t seq, void *ctxt) 1946 { 1947 Channel *c = NULL; 1948 char *ctype; 1949 int rchan; 1950 u_int rmaxpack, rwindow, len; 1951 1952 ctype = packet_get_string(&len); 1953 rchan = packet_get_int(); 1954 rwindow = packet_get_int(); 1955 rmaxpack = packet_get_int(); 1956 1957 debug("client_input_channel_open: ctype %s rchan %d win %d max %d", 1958 ctype, rchan, rwindow, rmaxpack); 1959 1960 if (strcmp(ctype, "forwarded-tcpip") == 0) { 1961 c = client_request_forwarded_tcpip(ctype, rchan); 1962 } else if (strcmp(ctype, "x11") == 0) { 1963 c = client_request_x11(ctype, rchan); 1964 } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) { 1965 c = client_request_agent(ctype, rchan); 1966 } 1967 /* XXX duplicate : */ 1968 if (c != NULL) { 1969 debug("confirm %s", ctype); 1970 c->remote_id = rchan; 1971 c->remote_window = rwindow; 1972 c->remote_maxpacket = rmaxpack; 1973 if (c->type != SSH_CHANNEL_CONNECTING) { 1974 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); 1975 packet_put_int(c->remote_id); 1976 packet_put_int(c->self); 1977 packet_put_int(c->local_window); 1978 packet_put_int(c->local_maxpacket); 1979 packet_send(); 1980 } 1981 } else { 1982 debug("failure %s", ctype); 1983 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); 1984 packet_put_int(rchan); 1985 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED); 1986 if (!(datafellows & SSH_BUG_OPENFAILURE)) { 1987 packet_put_cstring("open failed"); 1988 packet_put_cstring(""); 1989 } 1990 packet_send(); 1991 } 1992 xfree(ctype); 1993 } 1994 static void 1995 client_input_channel_req(int type, u_int32_t seq, void *ctxt) 1996 { 1997 Channel *c = NULL; 1998 int exitval, id, reply, success = 0; 1999 char *rtype; 2000 2001 id = packet_get_int(); 2002 rtype = packet_get_string(NULL); 2003 reply = packet_get_char(); 2004 2005 debug("client_input_channel_req: channel %d rtype %s reply %d", 2006 id, rtype, reply); 2007 2008 if (id == -1) { 2009 error("client_input_channel_req: request for channel -1"); 2010 } else if ((c = channel_lookup(id)) == NULL) { 2011 error("client_input_channel_req: channel %d: " 2012 "unknown channel", id); 2013 } else if (strcmp(rtype, "eow@openssh.com") == 0) { 2014 packet_check_eom(); 2015 chan_rcvd_eow(c); 2016 } else if (strcmp(rtype, "exit-status") == 0) { 2017 exitval = packet_get_int(); 2018 if (c->ctl_chan != -1) { 2019 mux_exit_message(c, exitval); 2020 success = 1; 2021 } else if (id == session_ident) { 2022 /* Record exit value of local session */ 2023 success = 1; 2024 exit_status = exitval; 2025 } else { 2026 /* Probably for a mux channel that has already closed */ 2027 debug("%s: no sink for exit-status on channel %d", 2028 __func__, id); 2029 } 2030 packet_check_eom(); 2031 } 2032 if (reply && c != NULL) { 2033 packet_start(success ? 2034 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE); 2035 packet_put_int(c->remote_id); 2036 packet_send(); 2037 } 2038 xfree(rtype); 2039 } 2040 static void 2041 client_input_global_request(int type, u_int32_t seq, void *ctxt) 2042 { 2043 char *rtype; 2044 int want_reply; 2045 int success = 0; 2046 2047 rtype = packet_get_string(NULL); 2048 want_reply = packet_get_char(); 2049 debug("client_input_global_request: rtype %s want_reply %d", 2050 rtype, want_reply); 2051 if (want_reply) { 2052 packet_start(success ? 2053 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE); 2054 packet_send(); 2055 packet_write_wait(); 2056 } 2057 xfree(rtype); 2058 } 2059 2060 void 2061 client_session2_setup(int id, int want_tty, int want_subsystem, 2062 const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env) 2063 { 2064 int len; 2065 Channel *c = NULL; 2066 2067 debug2("%s: id %d", __func__, id); 2068 2069 if ((c = channel_lookup(id)) == NULL) 2070 fatal("client_session2_setup: channel %d: unknown channel", id); 2071 2072 packet_set_interactive(want_tty, 2073 options.ip_qos_interactive, options.ip_qos_bulk); 2074 2075 if (want_tty) { 2076 struct winsize ws; 2077 2078 /* Store window size in the packet. */ 2079 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0) 2080 memset(&ws, 0, sizeof(ws)); 2081 2082 channel_request_start(id, "pty-req", 1); 2083 client_expect_confirm(id, "PTY allocation", CONFIRM_TTY); 2084 packet_put_cstring(term != NULL ? term : ""); 2085 packet_put_int((u_int)ws.ws_col); 2086 packet_put_int((u_int)ws.ws_row); 2087 packet_put_int((u_int)ws.ws_xpixel); 2088 packet_put_int((u_int)ws.ws_ypixel); 2089 if (tiop == NULL) 2090 tiop = get_saved_tio(); 2091 tty_make_modes(-1, tiop); 2092 packet_send(); 2093 /* XXX wait for reply */ 2094 c->client_tty = 1; 2095 } 2096 2097 /* Transfer any environment variables from client to server */ 2098 if (options.num_send_env != 0 && env != NULL) { 2099 int i, j, matched; 2100 char *name, *val; 2101 2102 debug("Sending environment."); 2103 for (i = 0; env[i] != NULL; i++) { 2104 /* Split */ 2105 name = xstrdup(env[i]); 2106 if ((val = strchr(name, '=')) == NULL) { 2107 xfree(name); 2108 continue; 2109 } 2110 *val++ = '\0'; 2111 2112 matched = 0; 2113 for (j = 0; j < options.num_send_env; j++) { 2114 if (match_pattern(name, options.send_env[j])) { 2115 matched = 1; 2116 break; 2117 } 2118 } 2119 if (!matched) { 2120 debug3("Ignored env %s", name); 2121 xfree(name); 2122 continue; 2123 } 2124 2125 debug("Sending env %s = %s", name, val); 2126 channel_request_start(id, "env", 0); 2127 packet_put_cstring(name); 2128 packet_put_cstring(val); 2129 packet_send(); 2130 xfree(name); 2131 } 2132 } 2133 2134 len = buffer_len(cmd); 2135 if (len > 0) { 2136 if (len > 900) 2137 len = 900; 2138 if (want_subsystem) { 2139 debug("Sending subsystem: %.*s", 2140 len, (u_char*)buffer_ptr(cmd)); 2141 channel_request_start(id, "subsystem", 1); 2142 client_expect_confirm(id, "subsystem", CONFIRM_CLOSE); 2143 } else { 2144 debug("Sending command: %.*s", 2145 len, (u_char*)buffer_ptr(cmd)); 2146 channel_request_start(id, "exec", 1); 2147 client_expect_confirm(id, "exec", CONFIRM_CLOSE); 2148 } 2149 packet_put_string(buffer_ptr(cmd), buffer_len(cmd)); 2150 packet_send(); 2151 } else { 2152 channel_request_start(id, "shell", 1); 2153 client_expect_confirm(id, "shell", CONFIRM_CLOSE); 2154 packet_send(); 2155 } 2156 } 2157 2158 static void 2159 client_init_dispatch_20(void) 2160 { 2161 dispatch_init(&dispatch_protocol_error); 2162 2163 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose); 2164 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data); 2165 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof); 2166 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data); 2167 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open); 2168 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); 2169 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); 2170 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req); 2171 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust); 2172 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm); 2173 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm); 2174 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request); 2175 2176 /* rekeying */ 2177 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit); 2178 2179 /* global request reply messages */ 2180 dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply); 2181 dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply); 2182 } 2183 2184 static void 2185 client_init_dispatch_13(void) 2186 { 2187 dispatch_init(NULL); 2188 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close); 2189 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation); 2190 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data); 2191 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); 2192 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); 2193 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open); 2194 dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status); 2195 dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data); 2196 dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data); 2197 2198 dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ? 2199 &client_input_agent_open : &deny_input_open); 2200 dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ? 2201 &x11_input_open : &deny_input_open); 2202 } 2203 2204 static void 2205 client_init_dispatch_15(void) 2206 { 2207 client_init_dispatch_13(); 2208 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof); 2209 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose); 2210 } 2211 2212 static void 2213 client_init_dispatch(void) 2214 { 2215 if (compat20) 2216 client_init_dispatch_20(); 2217 else if (compat13) 2218 client_init_dispatch_13(); 2219 else 2220 client_init_dispatch_15(); 2221 } 2222 2223 void 2224 client_stop_mux(void) 2225 { 2226 if (options.control_path != NULL && muxserver_sock != -1) 2227 unlink(options.control_path); 2228 /* 2229 * If we are in persist mode, or don't have a shell, signal that we 2230 * should close when all active channels are closed. 2231 */ 2232 if (options.control_persist || no_shell_flag) { 2233 session_closed = 1; 2234 setproctitle("[stopped mux]"); 2235 } 2236 } 2237 2238 /* client specific fatal cleanup */ 2239 void 2240 cleanup_exit(int i) 2241 { 2242 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE); 2243 leave_non_blocking(); 2244 if (options.control_path != NULL && muxserver_sock != -1) 2245 unlink(options.control_path); 2246 ssh_kill_proxy_command(); 2247 _exit(i); 2248 } 2249