1 /* $NetBSD: serverloop.c,v 1.12 2015/04/13 18:00:47 christos Exp $ */ 2 /* $OpenBSD: serverloop.c,v 1.178 2015/02/20 22:17:21 djm Exp $ */ 3 /* 4 * Author: Tatu Ylonen <ylo@cs.hut.fi> 5 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 6 * All rights reserved 7 * Server main loop for handling the interactive session. 8 * 9 * As far as I am concerned, the code I have written for this software 10 * can be used freely for any purpose. Any derived versions of this 11 * software must be clearly marked as such, and if the derived work is 12 * incompatible with the protocol description in the RFC file, it must be 13 * called by a name other than "ssh" or "Secure Shell". 14 * 15 * SSH2 support by Markus Friedl. 16 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. 17 * 18 * Redistribution and use in source and binary forms, with or without 19 * modification, are permitted provided that the following conditions 20 * are met: 21 * 1. Redistributions of source code must retain the above copyright 22 * notice, this list of conditions and the following disclaimer. 23 * 2. Redistributions in binary form must reproduce the above copyright 24 * notice, this list of conditions and the following disclaimer in the 25 * documentation and/or other materials provided with the distribution. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 28 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 29 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 30 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 31 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 32 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 33 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 34 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 35 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 36 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include "includes.h" 40 __RCSID("$NetBSD: serverloop.c,v 1.12 2015/04/13 18:00:47 christos Exp $"); 41 #include <sys/param.h> /* MIN MAX */ 42 #include <sys/types.h> 43 #include <sys/wait.h> 44 #include <sys/socket.h> 45 #include <sys/time.h> 46 #include <sys/queue.h> 47 48 #include <netinet/in.h> 49 50 #include <errno.h> 51 #include <fcntl.h> 52 #include <pwd.h> 53 #include <signal.h> 54 #include <string.h> 55 #include <termios.h> 56 #include <unistd.h> 57 #include <stdarg.h> 58 59 #include "xmalloc.h" 60 #include "packet.h" 61 #include "buffer.h" 62 #include "log.h" 63 #include "misc.h" 64 #include "servconf.h" 65 #include "canohost.h" 66 #include "sshpty.h" 67 #include "channels.h" 68 #include "compat.h" 69 #include "ssh1.h" 70 #include "ssh2.h" 71 #include "key.h" 72 #include "cipher.h" 73 #include "kex.h" 74 #include "hostfile.h" 75 #include "auth.h" 76 #include "session.h" 77 #include "dispatch.h" 78 #include "auth-options.h" 79 #include "serverloop.h" 80 #include "roaming.h" 81 #include "ssherr.h" 82 83 extern ServerOptions options; 84 85 /* XXX */ 86 extern Authctxt *the_authctxt; 87 extern int use_privsep; 88 89 static Buffer stdin_buffer; /* Buffer for stdin data. */ 90 static Buffer stdout_buffer; /* Buffer for stdout data. */ 91 static Buffer stderr_buffer; /* Buffer for stderr data. */ 92 static int fdin; /* Descriptor for stdin (for writing) */ 93 static int fdout; /* Descriptor for stdout (for reading); 94 May be same number as fdin. */ 95 static int fderr; /* Descriptor for stderr. May be -1. */ 96 static u_long stdin_bytes = 0; /* Number of bytes written to stdin. */ 97 static u_long stdout_bytes = 0; /* Number of stdout bytes sent to client. */ 98 static u_long stderr_bytes = 0; /* Number of stderr bytes sent to client. */ 99 static u_long fdout_bytes = 0; /* Number of stdout bytes read from program. */ 100 static int stdin_eof = 0; /* EOF message received from client. */ 101 static int fdout_eof = 0; /* EOF encountered reading from fdout. */ 102 static int fderr_eof = 0; /* EOF encountered readung from fderr. */ 103 static int fdin_is_tty = 0; /* fdin points to a tty. */ 104 static int connection_in; /* Connection to client (input). */ 105 static int connection_out; /* Connection to client (output). */ 106 static int connection_closed = 0; /* Connection to client closed. */ 107 static u_int buffer_high; /* "Soft" max buffer size. */ 108 static int no_more_sessions = 0; /* Disallow further sessions. */ 109 110 /* 111 * This SIGCHLD kludge is used to detect when the child exits. The server 112 * will exit after that, as soon as forwarded connections have terminated. 113 */ 114 115 static volatile sig_atomic_t child_terminated = 0; /* The child has terminated. */ 116 117 /* Cleanup on signals (!use_privsep case only) */ 118 static volatile sig_atomic_t received_sigterm = 0; 119 120 /* prototypes */ 121 static void server_init_dispatch(void); 122 123 /* 124 * Returns current time in seconds from Jan 1, 1970 with the maximum 125 * available resolution. 126 */ 127 128 static double 129 get_current_time(void) 130 { 131 struct timeval tv; 132 gettimeofday(&tv, NULL); 133 return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0; 134 } 135 136 /* 137 * we write to this pipe if a SIGCHLD is caught in order to avoid 138 * the race between select() and child_terminated 139 */ 140 static int notify_pipe[2]; 141 static void 142 notify_setup(void) 143 { 144 if (pipe(notify_pipe) < 0) { 145 error("pipe(notify_pipe) failed %s", strerror(errno)); 146 } else if ((fcntl(notify_pipe[0], F_SETFD, FD_CLOEXEC) == -1) || 147 (fcntl(notify_pipe[1], F_SETFD, FD_CLOEXEC) == -1)) { 148 error("fcntl(notify_pipe, F_SETFD) failed %s", strerror(errno)); 149 close(notify_pipe[0]); 150 close(notify_pipe[1]); 151 } else { 152 set_nonblock(notify_pipe[0]); 153 set_nonblock(notify_pipe[1]); 154 return; 155 } 156 notify_pipe[0] = -1; /* read end */ 157 notify_pipe[1] = -1; /* write end */ 158 } 159 static void 160 notify_parent(void) 161 { 162 if (notify_pipe[1] != -1) 163 (void)write(notify_pipe[1], "", 1); 164 } 165 static void 166 notify_prepare(fd_set *readset) 167 { 168 if (notify_pipe[0] != -1) 169 FD_SET(notify_pipe[0], readset); 170 } 171 static void 172 notify_done(fd_set *readset) 173 { 174 char c; 175 176 if (notify_pipe[0] != -1 && FD_ISSET(notify_pipe[0], readset)) 177 while (read(notify_pipe[0], &c, 1) != -1) 178 debug2("notify_done: reading"); 179 } 180 181 /*ARGSUSED*/ 182 static void 183 sigchld_handler(int sig) 184 { 185 int save_errno = errno; 186 child_terminated = 1; 187 signal(SIGCHLD, sigchld_handler); 188 notify_parent(); 189 errno = save_errno; 190 } 191 192 /*ARGSUSED*/ 193 static void 194 sigterm_handler(int sig) 195 { 196 received_sigterm = sig; 197 } 198 199 /* 200 * Make packets from buffered stderr data, and buffer it for sending 201 * to the client. 202 */ 203 static void 204 make_packets_from_stderr_data(void) 205 { 206 u_int len; 207 208 /* Send buffered stderr data to the client. */ 209 while (buffer_len(&stderr_buffer) > 0 && 210 packet_not_very_much_data_to_write()) { 211 len = buffer_len(&stderr_buffer); 212 if (packet_is_interactive()) { 213 if (len > 512) 214 len = 512; 215 } else { 216 /* Keep the packets at reasonable size. */ 217 if (len > packet_get_maxsize()) 218 len = packet_get_maxsize(); 219 } 220 packet_start(SSH_SMSG_STDERR_DATA); 221 packet_put_string(buffer_ptr(&stderr_buffer), len); 222 packet_send(); 223 buffer_consume(&stderr_buffer, len); 224 stderr_bytes += len; 225 } 226 } 227 228 /* 229 * Make packets from buffered stdout data, and buffer it for sending to the 230 * client. 231 */ 232 static void 233 make_packets_from_stdout_data(void) 234 { 235 u_int len; 236 237 /* Send buffered stdout data to the client. */ 238 while (buffer_len(&stdout_buffer) > 0 && 239 packet_not_very_much_data_to_write()) { 240 len = buffer_len(&stdout_buffer); 241 if (packet_is_interactive()) { 242 if (len > 512) 243 len = 512; 244 } else { 245 /* Keep the packets at reasonable size. */ 246 if (len > packet_get_maxsize()) 247 len = packet_get_maxsize(); 248 } 249 packet_start(SSH_SMSG_STDOUT_DATA); 250 packet_put_string(buffer_ptr(&stdout_buffer), len); 251 packet_send(); 252 buffer_consume(&stdout_buffer, len); 253 stdout_bytes += len; 254 } 255 } 256 257 static void 258 client_alive_check(void) 259 { 260 int channel_id; 261 262 /* timeout, check to see how many we have had */ 263 if (packet_inc_alive_timeouts() > options.client_alive_count_max) { 264 logit("Timeout, client not responding."); 265 cleanup_exit(255); 266 } 267 268 /* 269 * send a bogus global/channel request with "wantreply", 270 * we should get back a failure 271 */ 272 if ((channel_id = channel_find_open()) == -1) { 273 packet_start(SSH2_MSG_GLOBAL_REQUEST); 274 packet_put_cstring("keepalive@openssh.com"); 275 packet_put_char(1); /* boolean: want reply */ 276 } else { 277 channel_request_start(channel_id, "keepalive@openssh.com", 1); 278 } 279 packet_send(); 280 } 281 282 /* 283 * Sleep in select() until we can do something. This will initialize the 284 * select masks. Upon return, the masks will indicate which descriptors 285 * have data or can accept data. Optionally, a maximum time can be specified 286 * for the duration of the wait (0 = infinite). 287 */ 288 static void 289 wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, int *maxfdp, 290 u_int *nallocp, u_int64_t max_time_milliseconds) 291 { 292 struct timeval tv, *tvp; 293 int ret; 294 time_t minwait_secs = 0; 295 int client_alive_scheduled = 0; 296 297 /* Allocate and update select() masks for channel descriptors. */ 298 channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 299 &minwait_secs, 0); 300 301 if (minwait_secs != 0) 302 max_time_milliseconds = MIN(max_time_milliseconds, 303 (u_int)minwait_secs * 1000); 304 305 /* 306 * if using client_alive, set the max timeout accordingly, 307 * and indicate that this particular timeout was for client 308 * alive by setting the client_alive_scheduled flag. 309 * 310 * this could be randomized somewhat to make traffic 311 * analysis more difficult, but we're not doing it yet. 312 */ 313 if (compat20 && 314 max_time_milliseconds == 0 && options.client_alive_interval) { 315 client_alive_scheduled = 1; 316 max_time_milliseconds = 317 (u_int64_t)options.client_alive_interval * 1000; 318 } 319 320 if (compat20) { 321 #if 0 322 /* wrong: bad condition XXX */ 323 if (channel_not_very_much_buffered_data()) 324 #endif 325 FD_SET(connection_in, *readsetp); 326 } else { 327 /* 328 * Read packets from the client unless we have too much 329 * buffered stdin or channel data. 330 */ 331 if (buffer_len(&stdin_buffer) < buffer_high && 332 channel_not_very_much_buffered_data()) 333 FD_SET(connection_in, *readsetp); 334 /* 335 * If there is not too much data already buffered going to 336 * the client, try to get some more data from the program. 337 */ 338 if (packet_not_very_much_data_to_write()) { 339 if (!fdout_eof) 340 FD_SET(fdout, *readsetp); 341 if (!fderr_eof) 342 FD_SET(fderr, *readsetp); 343 } 344 /* 345 * If we have buffered data, try to write some of that data 346 * to the program. 347 */ 348 if (fdin != -1 && buffer_len(&stdin_buffer) > 0) 349 FD_SET(fdin, *writesetp); 350 } 351 notify_prepare(*readsetp); 352 353 /* 354 * If we have buffered packet data going to the client, mark that 355 * descriptor. 356 */ 357 if (packet_have_data_to_write()) 358 FD_SET(connection_out, *writesetp); 359 360 /* 361 * If child has terminated and there is enough buffer space to read 362 * from it, then read as much as is available and exit. 363 */ 364 if (child_terminated && packet_not_very_much_data_to_write()) 365 if (max_time_milliseconds == 0 || client_alive_scheduled) 366 max_time_milliseconds = 100; 367 368 if (max_time_milliseconds == 0) 369 tvp = NULL; 370 else { 371 tv.tv_sec = max_time_milliseconds / 1000; 372 tv.tv_usec = 1000 * (max_time_milliseconds % 1000); 373 tvp = &tv; 374 } 375 376 /* Wait for something to happen, or the timeout to expire. */ 377 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp); 378 379 if (ret == -1) { 380 memset(*readsetp, 0, *nallocp); 381 memset(*writesetp, 0, *nallocp); 382 if (errno != EINTR) 383 error("select: %.100s", strerror(errno)); 384 } else if (ret == 0 && client_alive_scheduled) 385 client_alive_check(); 386 387 notify_done(*readsetp); 388 } 389 390 /* 391 * Processes input from the client and the program. Input data is stored 392 * in buffers and processed later. 393 */ 394 static void 395 process_input(fd_set *readset) 396 { 397 int len; 398 char buf[16384]; 399 400 /* Read and buffer any input data from the client. */ 401 if (FD_ISSET(connection_in, readset)) { 402 int cont = 0; 403 len = roaming_read(connection_in, buf, sizeof(buf), &cont); 404 if (len == 0) { 405 if (cont) 406 return; 407 verbose("Connection closed by %.100s", 408 get_remote_ipaddr()); 409 connection_closed = 1; 410 if (compat20) 411 return; 412 cleanup_exit(255); 413 } else if (len < 0) { 414 if (errno != EINTR && errno != EAGAIN) { 415 verbose("Read error from remote host " 416 "%.100s: %.100s", 417 get_remote_ipaddr(), strerror(errno)); 418 cleanup_exit(255); 419 } 420 } else { 421 /* Buffer any received data. */ 422 packet_process_incoming(buf, len); 423 fdout_bytes += len; 424 } 425 } 426 if (compat20) 427 return; 428 429 /* Read and buffer any available stdout data from the program. */ 430 if (!fdout_eof && FD_ISSET(fdout, readset)) { 431 len = read(fdout, buf, sizeof(buf)); 432 if (len < 0 && (errno == EINTR || errno == EAGAIN)) { 433 /* do nothing */ 434 } else if (len <= 0) { 435 fdout_eof = 1; 436 } else { 437 buffer_append(&stdout_buffer, buf, len); 438 debug ("FD out now: %ld", fdout_bytes); 439 fdout_bytes += len; 440 } 441 } 442 /* Read and buffer any available stderr data from the program. */ 443 if (!fderr_eof && FD_ISSET(fderr, readset)) { 444 len = read(fderr, buf, sizeof(buf)); 445 if (len < 0 && (errno == EINTR || errno == EAGAIN)) { 446 /* do nothing */ 447 } else if (len <= 0) { 448 fderr_eof = 1; 449 } else { 450 buffer_append(&stderr_buffer, buf, len); 451 } 452 } 453 } 454 455 /* 456 * Sends data from internal buffers to client program stdin. 457 */ 458 static void 459 process_output(fd_set *writeset) 460 { 461 struct termios tio; 462 u_char *data; 463 u_int dlen; 464 int len; 465 466 /* Write buffered data to program stdin. */ 467 if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) { 468 data = buffer_ptr(&stdin_buffer); 469 dlen = buffer_len(&stdin_buffer); 470 len = write(fdin, data, dlen); 471 if (len < 0 && (errno == EINTR || errno == EAGAIN)) { 472 /* do nothing */ 473 } else if (len <= 0) { 474 if (fdin != fdout) 475 close(fdin); 476 else 477 shutdown(fdin, SHUT_WR); /* We will no longer send. */ 478 fdin = -1; 479 } else { 480 /* Successful write. */ 481 if (fdin_is_tty && dlen >= 1 && data[0] != '\r' && 482 tcgetattr(fdin, &tio) == 0 && 483 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { 484 /* 485 * Simulate echo to reduce the impact of 486 * traffic analysis 487 */ 488 packet_send_ignore(len); 489 packet_send(); 490 } 491 /* Consume the data from the buffer. */ 492 buffer_consume(&stdin_buffer, len); 493 /* Update the count of bytes written to the program. */ 494 stdin_bytes += len; 495 } 496 } 497 /* Send any buffered packet data to the client. */ 498 if (FD_ISSET(connection_out, writeset)) 499 stdin_bytes += packet_write_poll(); 500 } 501 502 /* 503 * Wait until all buffered output has been sent to the client. 504 * This is used when the program terminates. 505 */ 506 static void 507 drain_output(void) 508 { 509 /* Send any buffered stdout data to the client. */ 510 if (buffer_len(&stdout_buffer) > 0) { 511 packet_start(SSH_SMSG_STDOUT_DATA); 512 packet_put_string(buffer_ptr(&stdout_buffer), 513 buffer_len(&stdout_buffer)); 514 packet_send(); 515 /* Update the count of sent bytes. */ 516 stdout_bytes += buffer_len(&stdout_buffer); 517 } 518 /* Send any buffered stderr data to the client. */ 519 if (buffer_len(&stderr_buffer) > 0) { 520 packet_start(SSH_SMSG_STDERR_DATA); 521 packet_put_string(buffer_ptr(&stderr_buffer), 522 buffer_len(&stderr_buffer)); 523 packet_send(); 524 /* Update the count of sent bytes. */ 525 stderr_bytes += buffer_len(&stderr_buffer); 526 } 527 /* Wait until all buffered data has been written to the client. */ 528 packet_write_wait(); 529 } 530 531 static void 532 process_buffered_input_packets(void) 533 { 534 dispatch_run(DISPATCH_NONBLOCK, NULL, active_state); 535 } 536 537 /* 538 * Performs the interactive session. This handles data transmission between 539 * the client and the program. Note that the notion of stdin, stdout, and 540 * stderr in this function is sort of reversed: this function writes to 541 * stdin (of the child program), and reads from stdout and stderr (of the 542 * child program). 543 */ 544 void 545 server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg) 546 { 547 fd_set *readset = NULL, *writeset = NULL; 548 int max_fd = 0; 549 u_int nalloc = 0; 550 int wait_status; /* Status returned by wait(). */ 551 pid_t wait_pid; /* pid returned by wait(). */ 552 int waiting_termination = 0; /* Have displayed waiting close message. */ 553 u_int64_t max_time_milliseconds; 554 u_int previous_stdout_buffer_bytes; 555 u_int stdout_buffer_bytes; 556 int type; 557 558 debug("Entering interactive session."); 559 560 /* Initialize the SIGCHLD kludge. */ 561 child_terminated = 0; 562 signal(SIGCHLD, sigchld_handler); 563 564 if (!use_privsep) { 565 signal(SIGTERM, sigterm_handler); 566 signal(SIGINT, sigterm_handler); 567 signal(SIGQUIT, sigterm_handler); 568 } 569 570 /* Initialize our global variables. */ 571 fdin = fdin_arg; 572 fdout = fdout_arg; 573 fderr = fderr_arg; 574 575 /* nonblocking IO */ 576 set_nonblock(fdin); 577 set_nonblock(fdout); 578 /* we don't have stderr for interactive terminal sessions, see below */ 579 if (fderr != -1) 580 set_nonblock(fderr); 581 582 if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin)) 583 fdin_is_tty = 1; 584 585 connection_in = packet_get_connection_in(); 586 connection_out = packet_get_connection_out(); 587 588 notify_setup(); 589 590 previous_stdout_buffer_bytes = 0; 591 592 /* Set approximate I/O buffer size. */ 593 if (packet_is_interactive()) 594 buffer_high = 4096; 595 else 596 buffer_high = 64 * 1024; 597 598 #if 0 599 /* Initialize max_fd to the maximum of the known file descriptors. */ 600 max_fd = MAX(connection_in, connection_out); 601 max_fd = MAX(max_fd, fdin); 602 max_fd = MAX(max_fd, fdout); 603 if (fderr != -1) 604 max_fd = MAX(max_fd, fderr); 605 #endif 606 607 /* Initialize Initialize buffers. */ 608 buffer_init(&stdin_buffer); 609 buffer_init(&stdout_buffer); 610 buffer_init(&stderr_buffer); 611 612 /* 613 * If we have no separate fderr (which is the case when we have a pty 614 * - there we cannot make difference between data sent to stdout and 615 * stderr), indicate that we have seen an EOF from stderr. This way 616 * we don't need to check the descriptor everywhere. 617 */ 618 if (fderr == -1) 619 fderr_eof = 1; 620 621 server_init_dispatch(); 622 623 /* Main loop of the server for the interactive session mode. */ 624 for (;;) { 625 626 /* Process buffered packets from the client. */ 627 process_buffered_input_packets(); 628 629 /* 630 * If we have received eof, and there is no more pending 631 * input data, cause a real eof by closing fdin. 632 */ 633 if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) { 634 if (fdin != fdout) 635 close(fdin); 636 else 637 shutdown(fdin, SHUT_WR); /* We will no longer send. */ 638 fdin = -1; 639 } 640 /* Make packets from buffered stderr data to send to the client. */ 641 make_packets_from_stderr_data(); 642 643 /* 644 * Make packets from buffered stdout data to send to the 645 * client. If there is very little to send, this arranges to 646 * not send them now, but to wait a short while to see if we 647 * are getting more data. This is necessary, as some systems 648 * wake up readers from a pty after each separate character. 649 */ 650 max_time_milliseconds = 0; 651 stdout_buffer_bytes = buffer_len(&stdout_buffer); 652 if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 && 653 stdout_buffer_bytes != previous_stdout_buffer_bytes) { 654 /* try again after a while */ 655 max_time_milliseconds = 10; 656 } else { 657 /* Send it now. */ 658 make_packets_from_stdout_data(); 659 } 660 previous_stdout_buffer_bytes = buffer_len(&stdout_buffer); 661 662 /* Send channel data to the client. */ 663 if (packet_not_very_much_data_to_write()) 664 channel_output_poll(); 665 666 /* 667 * Bail out of the loop if the program has closed its output 668 * descriptors, and we have no more data to send to the 669 * client, and there is no pending buffered data. 670 */ 671 if (fdout_eof && fderr_eof && !packet_have_data_to_write() && 672 buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) { 673 if (!channel_still_open()) 674 break; 675 if (!waiting_termination) { 676 const char *s = "Waiting for forwarded connections to terminate...\r\n"; 677 char *cp; 678 waiting_termination = 1; 679 buffer_append(&stderr_buffer, s, strlen(s)); 680 681 /* Display list of open channels. */ 682 cp = channel_open_message(); 683 buffer_append(&stderr_buffer, cp, strlen(cp)); 684 free(cp); 685 } 686 } 687 max_fd = MAX(connection_in, connection_out); 688 max_fd = MAX(max_fd, fdin); 689 max_fd = MAX(max_fd, fdout); 690 max_fd = MAX(max_fd, fderr); 691 max_fd = MAX(max_fd, notify_pipe[0]); 692 693 /* Sleep in select() until we can do something. */ 694 wait_until_can_do_something(&readset, &writeset, &max_fd, 695 &nalloc, max_time_milliseconds); 696 697 if (received_sigterm) { 698 logit("Exiting on signal %d", (int)received_sigterm); 699 /* Clean up sessions, utmp, etc. */ 700 cleanup_exit(255); 701 } 702 703 /* Process any channel events. */ 704 channel_after_select(readset, writeset); 705 706 /* Process input from the client and from program stdout/stderr. */ 707 process_input(readset); 708 709 /* Process output to the client and to program stdin. */ 710 process_output(writeset); 711 } 712 free(readset); 713 free(writeset); 714 715 /* Cleanup and termination code. */ 716 717 /* Wait until all output has been sent to the client. */ 718 drain_output(); 719 720 debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.", 721 stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes); 722 723 /* Free and clear the buffers. */ 724 buffer_free(&stdin_buffer); 725 buffer_free(&stdout_buffer); 726 buffer_free(&stderr_buffer); 727 728 /* Close the file descriptors. */ 729 if (fdout != -1) 730 close(fdout); 731 fdout = -1; 732 fdout_eof = 1; 733 if (fderr != -1) 734 close(fderr); 735 fderr = -1; 736 fderr_eof = 1; 737 if (fdin != -1) 738 close(fdin); 739 fdin = -1; 740 741 channel_free_all(); 742 743 /* We no longer want our SIGCHLD handler to be called. */ 744 signal(SIGCHLD, SIG_DFL); 745 746 while ((wait_pid = waitpid(-1, &wait_status, 0)) < 0) 747 if (errno != EINTR) 748 packet_disconnect("wait: %.100s", strerror(errno)); 749 if (wait_pid != pid) 750 error("Strange, wait returned pid %ld, expected %ld", 751 (long)wait_pid, (long)pid); 752 753 /* Check if it exited normally. */ 754 if (WIFEXITED(wait_status)) { 755 /* Yes, normal exit. Get exit status and send it to the client. */ 756 debug("Command exited with status %d.", WEXITSTATUS(wait_status)); 757 packet_start(SSH_SMSG_EXITSTATUS); 758 packet_put_int(WEXITSTATUS(wait_status)); 759 packet_send(); 760 packet_write_wait(); 761 762 /* 763 * Wait for exit confirmation. Note that there might be 764 * other packets coming before it; however, the program has 765 * already died so we just ignore them. The client is 766 * supposed to respond with the confirmation when it receives 767 * the exit status. 768 */ 769 do { 770 type = packet_read(); 771 } 772 while (type != SSH_CMSG_EXIT_CONFIRMATION); 773 774 debug("Received exit confirmation."); 775 return; 776 } 777 /* Check if the program terminated due to a signal. */ 778 if (WIFSIGNALED(wait_status)) 779 packet_disconnect("Command terminated on signal %d.", 780 WTERMSIG(wait_status)); 781 782 /* Some weird exit cause. Just exit. */ 783 packet_disconnect("wait returned status %04x.", wait_status); 784 /* NOTREACHED */ 785 } 786 787 static void 788 collect_children(void) 789 { 790 pid_t pid; 791 sigset_t oset, nset; 792 int status; 793 794 /* block SIGCHLD while we check for dead children */ 795 sigemptyset(&nset); 796 sigaddset(&nset, SIGCHLD); 797 sigprocmask(SIG_BLOCK, &nset, &oset); 798 if (child_terminated) { 799 debug("Received SIGCHLD."); 800 while ((pid = waitpid(-1, &status, WNOHANG)) > 0 || 801 (pid < 0 && errno == EINTR)) 802 if (pid > 0) 803 session_close_by_pid(pid, status); 804 child_terminated = 0; 805 } 806 sigprocmask(SIG_SETMASK, &oset, NULL); 807 } 808 809 void 810 server_loop2(Authctxt *authctxt) 811 { 812 fd_set *readset = NULL, *writeset = NULL; 813 int rekeying = 0, max_fd; 814 u_int nalloc = 0; 815 u_int64_t rekey_timeout_ms = 0; 816 double start_time, total_time; 817 818 debug("Entering interactive session for SSH2."); 819 start_time = get_current_time(); 820 821 signal(SIGCHLD, sigchld_handler); 822 child_terminated = 0; 823 connection_in = packet_get_connection_in(); 824 connection_out = packet_get_connection_out(); 825 826 if (!use_privsep) { 827 signal(SIGTERM, sigterm_handler); 828 signal(SIGINT, sigterm_handler); 829 signal(SIGQUIT, sigterm_handler); 830 } 831 832 notify_setup(); 833 834 max_fd = MAX(connection_in, connection_out); 835 max_fd = MAX(max_fd, notify_pipe[0]); 836 837 server_init_dispatch(); 838 839 for (;;) { 840 process_buffered_input_packets(); 841 842 rekeying = (active_state->kex != NULL && !active_state->kex->done); 843 844 if (!rekeying && packet_not_very_much_data_to_write()) 845 channel_output_poll(); 846 if (options.rekey_interval > 0 && compat20 && !rekeying) 847 rekey_timeout_ms = packet_get_rekey_timeout() * 1000; 848 else 849 rekey_timeout_ms = 0; 850 851 wait_until_can_do_something(&readset, &writeset, &max_fd, 852 &nalloc, rekey_timeout_ms); 853 854 if (received_sigterm) { 855 logit("Exiting on signal %d", (int)received_sigterm); 856 /* Clean up sessions, utmp, etc. */ 857 cleanup_exit(255); 858 } 859 860 collect_children(); 861 if (!rekeying) { 862 channel_after_select(readset, writeset); 863 if (packet_need_rekeying()) { 864 int r; 865 debug("need rekeying"); 866 if (active_state->kex) 867 active_state->kex->done = 0; 868 if ((r = kex_send_kexinit(active_state)) != 0) 869 logit("%s: kex_send_kexinit: %s", 870 __func__, ssh_err(r)); 871 } 872 } 873 process_input(readset); 874 if (connection_closed) 875 break; 876 process_output(writeset); 877 } 878 collect_children(); 879 880 free(readset); 881 free(writeset); 882 883 /* free all channels, no more reads and writes */ 884 channel_free_all(); 885 886 /* free remaining sessions, e.g. remove wtmp entries */ 887 session_destroy_all(NULL); 888 total_time = get_current_time() - start_time; 889 logit("SSH: Server;LType: Throughput;Remote: %s-%d;IN: %lu;OUT: %lu;Duration: %.1f;tPut_in: %.1f;tPut_out: %.1f", 890 get_remote_ipaddr(), get_remote_port(), 891 stdin_bytes, fdout_bytes, total_time, stdin_bytes / total_time, 892 fdout_bytes / total_time); 893 } 894 895 static int 896 server_input_keep_alive(int type, u_int32_t seq, void *ctxt) 897 { 898 debug("Got %d/%u for keepalive", type, seq); 899 /* 900 * reset timeout, since we got a sane answer from the client. 901 * even if this was generated by something other than 902 * the bogus CHANNEL_REQUEST we send for keepalives. 903 */ 904 packet_set_alive_timeouts(0); 905 return 0; 906 } 907 908 static int 909 server_input_stdin_data(int type, u_int32_t seq, void *ctxt) 910 { 911 char *data; 912 u_int data_len; 913 914 /* Stdin data from the client. Append it to the buffer. */ 915 /* Ignore any data if the client has closed stdin. */ 916 if (fdin == -1) 917 return 0; 918 data = packet_get_string(&data_len); 919 packet_check_eom(); 920 buffer_append(&stdin_buffer, data, data_len); 921 explicit_bzero(data, data_len); 922 free(data); 923 return 0; 924 } 925 926 static int 927 server_input_eof(int type, u_int32_t seq, void *ctxt) 928 { 929 /* 930 * Eof from the client. The stdin descriptor to the 931 * program will be closed when all buffered data has 932 * drained. 933 */ 934 debug("EOF received for stdin."); 935 packet_check_eom(); 936 stdin_eof = 1; 937 return 0; 938 } 939 940 static int 941 server_input_window_size(int type, u_int32_t seq, void *ctxt) 942 { 943 u_int row = packet_get_int(); 944 u_int col = packet_get_int(); 945 u_int xpixel = packet_get_int(); 946 u_int ypixel = packet_get_int(); 947 948 debug("Window change received."); 949 packet_check_eom(); 950 if (fdin != -1) 951 pty_change_window_size(fdin, row, col, xpixel, ypixel); 952 return 0; 953 } 954 955 static Channel * 956 server_request_direct_tcpip(void) 957 { 958 Channel *c = NULL; 959 char *target, *originator; 960 u_short target_port, originator_port; 961 962 target = packet_get_string(NULL); 963 target_port = packet_get_int(); 964 originator = packet_get_string(NULL); 965 originator_port = packet_get_int(); 966 packet_check_eom(); 967 968 debug("server_request_direct_tcpip: originator %s port %d, target %s " 969 "port %d", originator, originator_port, target, target_port); 970 971 /* XXX fine grained permissions */ 972 if ((options.allow_tcp_forwarding & FORWARD_LOCAL) != 0 && 973 !no_port_forwarding_flag) { 974 c = channel_connect_to_port(target, target_port, 975 "direct-tcpip", "direct-tcpip"); 976 } else { 977 logit("refused local port forward: " 978 "originator %s port %d, target %s port %d", 979 originator, originator_port, target, target_port); 980 } 981 982 free(originator); 983 free(target); 984 985 return c; 986 } 987 988 static Channel * 989 server_request_direct_streamlocal(void) 990 { 991 Channel *c = NULL; 992 char *target, *originator; 993 u_short originator_port; 994 995 target = packet_get_string(NULL); 996 originator = packet_get_string(NULL); 997 originator_port = packet_get_int(); 998 packet_check_eom(); 999 1000 debug("server_request_direct_streamlocal: originator %s port %d, target %s", 1001 originator, originator_port, target); 1002 1003 /* XXX fine grained permissions */ 1004 if ((options.allow_streamlocal_forwarding & FORWARD_LOCAL) != 0 && 1005 !no_port_forwarding_flag) { 1006 c = channel_connect_to_path(target, 1007 "direct-streamlocal@openssh.com", "direct-streamlocal"); 1008 } else { 1009 logit("refused streamlocal port forward: " 1010 "originator %s port %d, target %s", 1011 originator, originator_port, target); 1012 } 1013 1014 free(originator); 1015 free(target); 1016 1017 return c; 1018 } 1019 1020 static Channel * 1021 server_request_tun(void) 1022 { 1023 Channel *c = NULL; 1024 int mode, tun; 1025 int sock; 1026 1027 mode = packet_get_int(); 1028 switch (mode) { 1029 case SSH_TUNMODE_POINTOPOINT: 1030 case SSH_TUNMODE_ETHERNET: 1031 break; 1032 default: 1033 packet_send_debug("Unsupported tunnel device mode."); 1034 return NULL; 1035 } 1036 if ((options.permit_tun & mode) == 0) { 1037 packet_send_debug("Server has rejected tunnel device " 1038 "forwarding"); 1039 return NULL; 1040 } 1041 1042 tun = packet_get_int(); 1043 if (forced_tun_device != -1) { 1044 if (tun != SSH_TUNID_ANY && forced_tun_device != tun) 1045 goto done; 1046 tun = forced_tun_device; 1047 } 1048 sock = tun_open(tun, mode); 1049 if (sock < 0) 1050 goto done; 1051 if (options.hpn_disabled) 1052 c = channel_new("tun", SSH_CHANNEL_OPEN, sock, sock, -1, 1053 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1); 1054 else 1055 c = channel_new("tun", SSH_CHANNEL_OPEN, sock, sock, -1, 1056 options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1); 1057 c->datagram = 1; 1058 1059 done: 1060 if (c == NULL) 1061 packet_send_debug("Failed to open the tunnel device."); 1062 return c; 1063 } 1064 1065 static Channel * 1066 server_request_session(void) 1067 { 1068 Channel *c; 1069 1070 debug("input_session_request"); 1071 packet_check_eom(); 1072 1073 if (no_more_sessions) { 1074 packet_disconnect("Possible attack: attempt to open a session " 1075 "after additional sessions disabled"); 1076 } 1077 1078 /* 1079 * A server session has no fd to read or write until a 1080 * CHANNEL_REQUEST for a shell is made, so we set the type to 1081 * SSH_CHANNEL_LARVAL. Additionally, a callback for handling all 1082 * CHANNEL_REQUEST messages is registered. 1083 */ 1084 c = channel_new("session", SSH_CHANNEL_LARVAL, 1085 -1, -1, -1, /*window size*/0, CHAN_SES_PACKET_DEFAULT, 1086 0, "server-session", 1); 1087 if ((options.tcp_rcv_buf_poll > 0) && (!options.hpn_disabled)) 1088 c->dynamic_window = 1; 1089 if (session_open(the_authctxt, c->self) != 1) { 1090 debug("session open failed, free channel %d", c->self); 1091 channel_free(c); 1092 return NULL; 1093 } 1094 channel_register_cleanup(c->self, session_close_by_channel, 0); 1095 return c; 1096 } 1097 1098 static int 1099 server_input_channel_open(int type, u_int32_t seq, void *ctxt) 1100 { 1101 Channel *c = NULL; 1102 char *ctype; 1103 int rchan; 1104 u_int rmaxpack, rwindow, len; 1105 1106 ctype = packet_get_string(&len); 1107 rchan = packet_get_int(); 1108 rwindow = packet_get_int(); 1109 rmaxpack = packet_get_int(); 1110 1111 debug("server_input_channel_open: ctype %s rchan %d win %d max %d", 1112 ctype, rchan, rwindow, rmaxpack); 1113 1114 if (strcmp(ctype, "session") == 0) { 1115 c = server_request_session(); 1116 } else if (strcmp(ctype, "direct-tcpip") == 0) { 1117 c = server_request_direct_tcpip(); 1118 } else if (strcmp(ctype, "direct-streamlocal@openssh.com") == 0) { 1119 c = server_request_direct_streamlocal(); 1120 } else if (strcmp(ctype, "tun@openssh.com") == 0) { 1121 c = server_request_tun(); 1122 } 1123 if (c != NULL) { 1124 debug("server_input_channel_open: confirm %s", ctype); 1125 c->remote_id = rchan; 1126 c->remote_window = rwindow; 1127 c->remote_maxpacket = rmaxpack; 1128 if (c->type != SSH_CHANNEL_CONNECTING) { 1129 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); 1130 packet_put_int(c->remote_id); 1131 packet_put_int(c->self); 1132 packet_put_int(c->local_window); 1133 packet_put_int(c->local_maxpacket); 1134 packet_send(); 1135 } 1136 } else { 1137 debug("server_input_channel_open: failure %s", ctype); 1138 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); 1139 packet_put_int(rchan); 1140 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED); 1141 if (!(datafellows & SSH_BUG_OPENFAILURE)) { 1142 packet_put_cstring("open failed"); 1143 packet_put_cstring(""); 1144 } 1145 packet_send(); 1146 } 1147 free(ctype); 1148 return 0; 1149 } 1150 1151 static int 1152 server_input_hostkeys_prove(struct sshbuf **respp) 1153 { 1154 struct ssh *ssh = active_state; /* XXX */ 1155 struct sshbuf *resp = NULL; 1156 struct sshbuf *sigbuf = NULL; 1157 struct sshkey *key = NULL, *key_pub = NULL, *key_prv = NULL; 1158 int r, ndx, success = 0; 1159 const u_char *blob; 1160 u_char *sig = 0; 1161 size_t blen, slen; 1162 1163 if ((resp = sshbuf_new()) == NULL || (sigbuf = sshbuf_new()) == NULL) 1164 fatal("%s: sshbuf_new", __func__); 1165 1166 while (ssh_packet_remaining(ssh) > 0) { 1167 sshkey_free(key); 1168 key = NULL; 1169 if ((r = sshpkt_get_string_direct(ssh, &blob, &blen)) != 0 || 1170 (r = sshkey_from_blob(blob, blen, &key)) != 0) { 1171 error("%s: couldn't parse key: %s", 1172 __func__, ssh_err(r)); 1173 goto out; 1174 } 1175 /* 1176 * Better check that this is actually one of our hostkeys 1177 * before attempting to sign anything with it. 1178 */ 1179 if ((ndx = ssh->kex->host_key_index(key, 1, ssh)) == -1) { 1180 error("%s: unknown host %s key", 1181 __func__, sshkey_type(key)); 1182 goto out; 1183 } 1184 /* 1185 * XXX refactor: make kex->sign just use an index rather 1186 * than passing in public and private keys 1187 */ 1188 if ((key_prv = get_hostkey_by_index(ndx)) == NULL && 1189 (key_pub = get_hostkey_public_by_index(ndx, ssh)) == NULL) { 1190 error("%s: can't retrieve hostkey %d", __func__, ndx); 1191 goto out; 1192 } 1193 sshbuf_reset(sigbuf); 1194 free(sig); 1195 sig = NULL; 1196 if ((r = sshbuf_put_cstring(sigbuf, 1197 "hostkeys-prove-00@openssh.com")) != 0 || 1198 (r = sshbuf_put_string(sigbuf, 1199 ssh->kex->session_id, ssh->kex->session_id_len)) != 0 || 1200 (r = sshkey_puts(key, sigbuf)) != 0 || 1201 (r = ssh->kex->sign(key_prv, key_pub, &sig, &slen, 1202 sshbuf_ptr(sigbuf), sshbuf_len(sigbuf), 0)) != 0 || 1203 (r = sshbuf_put_string(resp, sig, slen)) != 0) { 1204 error("%s: couldn't prepare signature: %s", 1205 __func__, ssh_err(r)); 1206 goto out; 1207 } 1208 } 1209 /* Success */ 1210 *respp = resp; 1211 resp = NULL; /* don't free it */ 1212 success = 1; 1213 out: 1214 free(sig); 1215 sshbuf_free(resp); 1216 sshbuf_free(sigbuf); 1217 sshkey_free(key); 1218 return success; 1219 } 1220 1221 static int 1222 server_input_global_request(int type, u_int32_t seq, void *ctxt) 1223 { 1224 char *rtype; 1225 int want_reply; 1226 int r, success = 0, allocated_listen_port = 0; 1227 struct sshbuf *resp = NULL; 1228 1229 rtype = packet_get_string(NULL); 1230 want_reply = packet_get_char(); 1231 debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply); 1232 1233 /* -R style forwarding */ 1234 if (strcmp(rtype, "tcpip-forward") == 0) { 1235 struct passwd *pw; 1236 struct Forward fwd; 1237 1238 pw = the_authctxt->pw; 1239 if (pw == NULL || !the_authctxt->valid) 1240 fatal("server_input_global_request: no/invalid user"); 1241 memset(&fwd, 0, sizeof(fwd)); 1242 fwd.listen_host = packet_get_string(NULL); 1243 fwd.listen_port = (u_short)packet_get_int(); 1244 debug("server_input_global_request: tcpip-forward listen %s port %d", 1245 fwd.listen_host, fwd.listen_port); 1246 1247 /* check permissions */ 1248 if ((options.allow_tcp_forwarding & FORWARD_REMOTE) == 0 || 1249 no_port_forwarding_flag || 1250 (!want_reply && fwd.listen_port == 0) || 1251 (fwd.listen_port != 0 && fwd.listen_port < IPPORT_RESERVED && 1252 pw->pw_uid != 0)) { 1253 success = 0; 1254 packet_send_debug("Server has disabled port forwarding."); 1255 } else { 1256 /* Start listening on the port */ 1257 success = channel_setup_remote_fwd_listener(&fwd, 1258 &allocated_listen_port, &options.fwd_opts); 1259 } 1260 free(fwd.listen_host); 1261 if ((resp = sshbuf_new()) == NULL) 1262 fatal("%s: sshbuf_new", __func__); 1263 if ((r = sshbuf_put_u32(resp, allocated_listen_port)) != 0) 1264 fatal("%s: sshbuf_put_u32: %s", __func__, ssh_err(r)); 1265 } else if (strcmp(rtype, "cancel-tcpip-forward") == 0) { 1266 struct Forward fwd; 1267 1268 memset(&fwd, 0, sizeof(fwd)); 1269 fwd.listen_host = packet_get_string(NULL); 1270 fwd.listen_port = (u_short)packet_get_int(); 1271 debug("%s: cancel-tcpip-forward addr %s port %d", __func__, 1272 fwd.listen_host, fwd.listen_port); 1273 1274 success = channel_cancel_rport_listener(&fwd); 1275 free(fwd.listen_host); 1276 } else if (strcmp(rtype, "streamlocal-forward@openssh.com") == 0) { 1277 struct Forward fwd; 1278 1279 memset(&fwd, 0, sizeof(fwd)); 1280 fwd.listen_path = packet_get_string(NULL); 1281 debug("server_input_global_request: streamlocal-forward listen path %s", 1282 fwd.listen_path); 1283 1284 /* check permissions */ 1285 if ((options.allow_streamlocal_forwarding & FORWARD_REMOTE) == 0 1286 || no_port_forwarding_flag) { 1287 success = 0; 1288 packet_send_debug("Server has disabled port forwarding."); 1289 } else { 1290 /* Start listening on the socket */ 1291 success = channel_setup_remote_fwd_listener( 1292 &fwd, NULL, &options.fwd_opts); 1293 } 1294 free(fwd.listen_path); 1295 } else if (strcmp(rtype, "cancel-streamlocal-forward@openssh.com") == 0) { 1296 struct Forward fwd; 1297 1298 memset(&fwd, 0, sizeof(fwd)); 1299 fwd.listen_path = packet_get_string(NULL); 1300 debug("%s: cancel-streamlocal-forward path %s", __func__, 1301 fwd.listen_path); 1302 1303 success = channel_cancel_rport_listener(&fwd); 1304 free(fwd.listen_path); 1305 } else if (strcmp(rtype, "no-more-sessions@openssh.com") == 0) { 1306 no_more_sessions = 1; 1307 success = 1; 1308 } else if (strcmp(rtype, "hostkeys-prove-00@openssh.com") == 0) { 1309 success = server_input_hostkeys_prove(&resp); 1310 } 1311 if (want_reply) { 1312 packet_start(success ? 1313 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE); 1314 if (success && resp != NULL) 1315 ssh_packet_put_raw(active_state, sshbuf_ptr(resp), 1316 sshbuf_len(resp)); 1317 packet_send(); 1318 packet_write_wait(); 1319 } 1320 free(rtype); 1321 sshbuf_free(resp); 1322 return 0; 1323 } 1324 1325 static int 1326 server_input_channel_req(int type, u_int32_t seq, void *ctxt) 1327 { 1328 Channel *c; 1329 int id, reply, success = 0; 1330 char *rtype; 1331 1332 id = packet_get_int(); 1333 rtype = packet_get_string(NULL); 1334 reply = packet_get_char(); 1335 1336 debug("server_input_channel_req: channel %d request %s reply %d", 1337 id, rtype, reply); 1338 1339 if ((c = channel_lookup(id)) == NULL) 1340 packet_disconnect("server_input_channel_req: " 1341 "unknown channel %d", id); 1342 if (!strcmp(rtype, "eow@openssh.com")) { 1343 packet_check_eom(); 1344 chan_rcvd_eow(c); 1345 } else if ((c->type == SSH_CHANNEL_LARVAL || 1346 c->type == SSH_CHANNEL_OPEN) && strcmp(c->ctype, "session") == 0) 1347 success = session_input_channel_req(c, rtype); 1348 if (reply && !(c->flags & CHAN_CLOSE_SENT)) { 1349 packet_start(success ? 1350 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE); 1351 packet_put_int(c->remote_id); 1352 packet_send(); 1353 } 1354 free(rtype); 1355 return 0; 1356 } 1357 1358 static void 1359 server_init_dispatch_20(void) 1360 { 1361 debug("server_init_dispatch_20"); 1362 dispatch_init(&dispatch_protocol_error); 1363 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose); 1364 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data); 1365 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof); 1366 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data); 1367 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open); 1368 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); 1369 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); 1370 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &server_input_channel_req); 1371 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust); 1372 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &server_input_global_request); 1373 /* client_alive */ 1374 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &server_input_keep_alive); 1375 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &server_input_keep_alive); 1376 dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &server_input_keep_alive); 1377 dispatch_set(SSH2_MSG_REQUEST_FAILURE, &server_input_keep_alive); 1378 /* rekeying */ 1379 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit); 1380 } 1381 static void 1382 server_init_dispatch_13(void) 1383 { 1384 debug("server_init_dispatch_13"); 1385 dispatch_init(NULL); 1386 dispatch_set(SSH_CMSG_EOF, &server_input_eof); 1387 dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data); 1388 dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size); 1389 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close); 1390 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation); 1391 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data); 1392 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); 1393 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); 1394 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open); 1395 } 1396 static void 1397 server_init_dispatch_15(void) 1398 { 1399 server_init_dispatch_13(); 1400 debug("server_init_dispatch_15"); 1401 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof); 1402 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose); 1403 } 1404 static void 1405 server_init_dispatch(void) 1406 { 1407 if (compat20) 1408 server_init_dispatch_20(); 1409 else if (compat13) 1410 server_init_dispatch_13(); 1411 else 1412 server_init_dispatch_15(); 1413 } 1414