clientloop.c

   1 /*
   2  * Author: Tatu Ylonen <ylo@cs.hut.fi>
   3  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
   4  *                    All rights reserved
   5  * The main loop for the interactive session (client side).
   6  *
   7  * As far as I am concerned, the code I have written for this software
   8  * can be used freely for any purpose.  Any derived versions of this
   9  * software must be clearly marked as such, and if the derived work is
  10  * incompatible with the protocol description in the RFC file, it must be
  11  * called by a name other than "ssh" or "Secure Shell".
  12  *
  13  *
  14  * Copyright (c) 1999 Theo de Raadt.  All rights reserved.
  15  *
  16  * Redistribution and use in source and binary forms, with or without
  17  * modification, are permitted provided that the following conditions
  18  * are met:
  19  * 1. Redistributions of source code must retain the above copyright
  20  *    notice, this list of conditions and the following disclaimer.
  21  * 2. Redistributions in binary form must reproduce the above copyright
  22  *    notice, this list of conditions and the following disclaimer in the
  23  *    documentation and/or other materials provided with the distribution.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  26  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  27  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  28  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  29  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  30  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  31  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  34  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  *
  36  *
  37  * SSH2 support added by Markus Friedl.
  38  * Copyright (c) 1999, 2000, 2001 Markus Friedl.  All rights reserved.
  39  *
  40  * Redistribution and use in source and binary forms, with or without
  41  * modification, are permitted provided that the following conditions
  42  * are met:
  43  * 1. Redistributions of source code must retain the above copyright
  44  *    notice, this list of conditions and the following disclaimer.
  45  * 2. Redistributions in binary form must reproduce the above copyright
  46  *    notice, this list of conditions and the following disclaimer in the
  47  *    documentation and/or other materials provided with the distribution.
  48  *
  49  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  50  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  51  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  52  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  53  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  54  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  55  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  56  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  57  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  58  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  59  */
  60
  61 #include "includes.h"
  62 RCSID("$OpenBSD: clientloop.c,v 1.84 2001/10/11 15:24:00 markus Exp $");
  63
  64 #include "ssh.h"
  65 #include "ssh1.h"
  66 #include "ssh2.h"
  67 #include "xmalloc.h"
  68 #include "packet.h"
  69 #include "buffer.h"
  70 #include "compat.h"
  71 #include "channels.h"
  72 #include "dispatch.h"
  73 #include "buffer.h"
  74 #include "bufaux.h"
  75 #include "key.h"
  76 #include "kex.h"
  77 #include "log.h"
  78 #include "readconf.h"
  79 #include "clientloop.h"
  80 #include "authfd.h"
  81 #include "atomicio.h"
  82 #include "sshtty.h"
  83 #include "misc.h"
  84
  85 /* import options */
  86 extern Options options;
  87
  88 /* Flag indicating that stdin should be redirected from /dev/null. */
  89 extern int stdin_null_flag;
  90
  91 /*
  92  * Name of the host we are connecting to.  This is the name given on the
  93  * command line, or the HostName specified for the user-supplied name in a
  94  * configuration file.
  95  */
  96 extern char *host;
  97
  98 /*
  99  * Flag to indicate that we have received a window change signal which has
 100  * not yet been processed.  This will cause a message indicating the new
 101  * window size to be sent to the server a little later.  This is volatile
 102  * because this is updated in a signal handler.
 103  */
 104 static volatile int received_window_change_signal = 0;
 105 static volatile int received_signal = 0;
 106
 107 /* Flag indicating whether the user\'s terminal is in non-blocking mode. */
 108 static int in_non_blocking_mode = 0;
 109
 110 /* Common data for the client loop code. */
 111 static int quit_pending;        /* Set to non-zero to quit the client loop. */
 112 static int escape_char;         /* Escape character. */
 113 static int escape_pending;      /* Last character was the escape character */
 114 static int last_was_cr;         /* Last character was a newline. */
 115 static int exit_status;         /* Used to store the exit status of the command. */
 116 static int stdin_eof;           /* EOF has been encountered on standard error. */
 117 static Buffer stdin_buffer;     /* Buffer for stdin data. */
 118 static Buffer stdout_buffer;    /* Buffer for stdout data. */
 119 static Buffer stderr_buffer;    /* Buffer for stderr data. */
 120 static u_long stdin_bytes, stdout_bytes, stderr_bytes;
 121 static u_int buffer_high;/* Soft max buffer size. */
 122 static int connection_in;       /* Connection to server (input). */
 123 static int connection_out;      /* Connection to server (output). */
 124 static int need_rekeying;       /* Set to non-zero if rekeying is requested. */
 125 static int session_closed = 0;  /* In SSH2: login session closed. */
 126
 127 static void client_init_dispatch(void);
 128 int     session_ident = -1;
 129
 130 /*XXX*/
 131 extern Kex *xxx_kex;
 132
 133 /* Restores stdin to blocking mode. */
 134
 135 static void
 136 leave_non_blocking(void)
 137 {
 138         if (in_non_blocking_mode) {
 139                 (void) fcntl(fileno(stdin), F_SETFL, 0);
 140                 in_non_blocking_mode = 0;
 141                 fatal_remove_cleanup((void (*) (void *)) leave_non_blocking, NULL);
 142         }
 143 }
 144
 145 /* Puts stdin terminal in non-blocking mode. */
 146
 147 static void
 148 enter_non_blocking(void)
 149 {
 150         in_non_blocking_mode = 1;
 151         (void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
 152         fatal_add_cleanup((void (*) (void *)) leave_non_blocking, NULL);
 153 }
 154
 155 /*
 156  * Signal handler for the window change signal (SIGWINCH).  This just sets a
 157  * flag indicating that the window has changed.
 158  */
 159
 160 static void
 161 window_change_handler(int sig)
 162 {
 163         received_window_change_signal = 1;
 164         signal(SIGWINCH, window_change_handler);
 165 }
 166
 167 /*
 168  * Signal handler for signals that cause the program to terminate.  These
 169  * signals must be trapped to restore terminal modes.
 170  */
 171
 172 static void
 173 signal_handler(int sig)
 174 {
 175         received_signal = sig;
 176         quit_pending = 1;
 177 }
 178
 179 /*
 180  * Returns current time in seconds from Jan 1, 1970 with the maximum
 181  * available resolution.
 182  */
 183
 184 static double
 185 get_current_time(void)
 186 {
 187         struct timeval tv;
 188         gettimeofday(&tv, NULL);
 189         return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
 190 }
 191
 192 /*
 193  * This is called when the interactive is entered.  This checks if there is
 194  * an EOF coming on stdin.  We must check this explicitly, as select() does
 195  * not appear to wake up when redirecting from /dev/null.
 196  */
 197
 198 static void
 199 client_check_initial_eof_on_stdin(void)
 200 {
 201         int len;
 202         char buf[1];
 203
 204         /*
 205          * If standard input is to be "redirected from /dev/null", we simply
 206          * mark that we have seen an EOF and send an EOF message to the
 207          * server. Otherwise, we try to read a single character; it appears
 208          * that for some files, such /dev/null, select() never wakes up for
 209          * read for this descriptor, which means that we never get EOF.  This
 210          * way we will get the EOF if stdin comes from /dev/null or similar.
 211          */
 212         if (stdin_null_flag) {
 213                 /* Fake EOF on stdin. */
 214                 debug("Sending eof.");
 215                 stdin_eof = 1;
 216                 packet_start(SSH_CMSG_EOF);
 217                 packet_send();
 218         } else {
 219                 enter_non_blocking();
 220
 221                 /* Check for immediate EOF on stdin. */
 222                 len = read(fileno(stdin), buf, 1);
 223                 if (len == 0) {
 224                         /* EOF.  Record that we have seen it and send EOF to server. */
 225                         debug("Sending eof.");
 226                         stdin_eof = 1;
 227                         packet_start(SSH_CMSG_EOF);
 228                         packet_send();
 229                 } else if (len > 0) {
 230                         /*
 231                          * Got data.  We must store the data in the buffer,
 232                          * and also process it as an escape character if
 233                          * appropriate.
 234                          */
 235                         if ((u_char) buf[0] == escape_char)
 236                                 escape_pending = 1;
 237                         else
 238                                 buffer_append(&stdin_buffer, buf, 1);
 239                 }
 240                 leave_non_blocking();
 241         }
 242 }
 243
 244
 245 /*
 246  * Make packets from buffered stdin data, and buffer them for sending to the
 247  * connection.
 248  */
 249
 250 static void
 251 client_make_packets_from_stdin_data(void)
 252 {
 253         u_int len;
 254
 255         /* Send buffered stdin data to the server. */
 256         while (buffer_len(&stdin_buffer) > 0 &&
 257                packet_not_very_much_data_to_write()) {
 258                 len = buffer_len(&stdin_buffer);
 259                 /* Keep the packets at reasonable size. */
 260                 if (len > packet_get_maxsize())
 261                         len = packet_get_maxsize();
 262                 packet_start(SSH_CMSG_STDIN_DATA);
 263                 packet_put_string(buffer_ptr(&stdin_buffer), len);
 264                 packet_send();
 265                 buffer_consume(&stdin_buffer, len);
 266                 stdin_bytes += len;
 267                 /* If we have a pending EOF, send it now. */
 268                 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
 269                         packet_start(SSH_CMSG_EOF);
 270                         packet_send();
 271                 }
 272         }
 273 }
 274
 275 /*
 276  * Checks if the client window has changed, and sends a packet about it to
 277  * the server if so.  The actual change is detected elsewhere (by a software
 278  * interrupt on Unix); this just checks the flag and sends a message if
 279  * appropriate.
 280  */
 281
 282 static void
 283 client_check_window_change(void)
 284 {
 285         struct winsize ws;
 286
 287         if (! received_window_change_signal)
 288                 return;
 289         /** XXX race */
 290         received_window_change_signal = 0;
 291
 292         if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
 293                 return;
 294
 295         debug2("client_check_window_change: changed");
 296
 297         if (compat20) {
 298                 channel_request_start(session_ident, "window-change", 0);
 299                 packet_put_int(ws.ws_col);
 300                 packet_put_int(ws.ws_row);
 301                 packet_put_int(ws.ws_xpixel);
 302                 packet_put_int(ws.ws_ypixel);
 303                 packet_send();
 304         } else {
 305                 packet_start(SSH_CMSG_WINDOW_SIZE);
 306                 packet_put_int(ws.ws_row);
 307                 packet_put_int(ws.ws_col);
 308                 packet_put_int(ws.ws_xpixel);
 309                 packet_put_int(ws.ws_ypixel);
 310                 packet_send();
 311         }
 312 }
 313
 314 /*
 315  * Waits until the client can do something (some data becomes available on
 316  * one of the file descriptors).
 317  */
 318
 319 static void
 320 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
 321     int *maxfdp, int *nallocp, int rekeying)
 322 {
 323         /* Add any selections by the channel mechanism. */
 324         channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
 325
 326         if (!compat20) {
 327                 /* Read from the connection, unless our buffers are full. */
 328                 if (buffer_len(&stdout_buffer) < buffer_high &&
 329                     buffer_len(&stderr_buffer) < buffer_high &&
 330                     channel_not_very_much_buffered_data())
 331                         FD_SET(connection_in, *readsetp);
 332                 /*
 333                  * Read from stdin, unless we have seen EOF or have very much
 334                  * buffered data to send to the server.
 335                  */
 336                 if (!stdin_eof && packet_not_very_much_data_to_write())
 337                         FD_SET(fileno(stdin), *readsetp);
 338
 339                 /* Select stdout/stderr if have data in buffer. */
 340                 if (buffer_len(&stdout_buffer) > 0)
 341                         FD_SET(fileno(stdout), *writesetp);
 342                 if (buffer_len(&stderr_buffer) > 0)
 343                         FD_SET(fileno(stderr), *writesetp);
 344         } else {
 345                 /* channel_prepare_select could have closed the last channel */
 346                 if (session_closed && !channel_still_open() &&
 347                     !packet_have_data_to_write()) {
 348                         /* clear mask since we did not call select() */
 349                         memset(*readsetp, 0, *maxfdp);
 350                         memset(*writesetp, 0, *maxfdp);
 351                         return;
 352                 } else {
 353                         FD_SET(connection_in, *readsetp);
 354                 }
 355         }
 356
 357         /* Select server connection if have data to write to the server. */
 358         if (packet_have_data_to_write())
 359                 FD_SET(connection_out, *writesetp);
 360
 361         /*
 362          * Wait for something to happen.  This will suspend the process until
 363          * some selected descriptor can be read, written, or has some other
 364          * event pending. Note: if you want to implement SSH_MSG_IGNORE
 365          * messages to fool traffic analysis, this might be the place to do
 366          * it: just have a random timeout for the select, and send a random
 367          * SSH_MSG_IGNORE packet when the timeout expires.
 368          */
 369
 370         if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) {
 371                 char buf[100];
 372
 373                 /*
 374                  * We have to clear the select masks, because we return.
 375                  * We have to return, because the mainloop checks for the flags
 376                  * set by the signal handlers.
 377                  */
 378                 memset(*readsetp, 0, *maxfdp);
 379                 memset(*writesetp, 0, *maxfdp);
 380
 381                 if (errno == EINTR)
 382                         return;
 383                 /* Note: we might still have data in the buffers. */
 384                 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
 385                 buffer_append(&stderr_buffer, buf, strlen(buf));
 386                 quit_pending = 1;
 387         }
 388 }
 389
 390 static void
 391 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
 392 {
 393         struct winsize oldws, newws;
 394
 395         /* Flush stdout and stderr buffers. */
 396         if (buffer_len(bout) > 0)
 397                 atomicio(write, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
 398         if (buffer_len(berr) > 0)
 399                 atomicio(write, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
 400
 401         leave_raw_mode();
 402
 403         /*
 404          * Free (and clear) the buffer to reduce the amount of data that gets
 405          * written to swap.
 406          */
 407         buffer_free(bin);
 408         buffer_free(bout);
 409         buffer_free(berr);
 410
 411         /* Save old window size. */
 412         ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
 413
 414         /* Send the suspend signal to the program itself. */
 415         kill(getpid(), SIGTSTP);
 416
 417         /* Check if the window size has changed. */
 418         if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 &&
 419             (oldws.ws_row != newws.ws_row ||
 420              oldws.ws_col != newws.ws_col ||
 421              oldws.ws_xpixel != newws.ws_xpixel ||
 422              oldws.ws_ypixel != newws.ws_ypixel))
 423                 received_window_change_signal = 1;
 424
 425         /* OK, we have been continued by the user. Reinitialize buffers. */
 426         buffer_init(bin);
 427         buffer_init(bout);
 428         buffer_init(berr);
 429
 430         enter_raw_mode();
 431 }
 432
 433 static void
 434 client_process_net_input(fd_set * readset)
 435 {
 436         int len;
 437         char buf[8192];
 438
 439         /*
 440          * Read input from the server, and add any such data to the buffer of
 441          * the packet subsystem.
 442          */
 443         if (FD_ISSET(connection_in, readset)) {
 444                 /* Read as much as possible. */
 445                 len = read(connection_in, buf, sizeof(buf));
 446                 if (len == 0) {
 447                         /* Received EOF.  The remote host has closed the connection. */
 448                         snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
 449                                  host);
 450                         buffer_append(&stderr_buffer, buf, strlen(buf));
 451                         quit_pending = 1;
 452                         return;
 453                 }
 454                 /*
 455                  * There is a kernel bug on Solaris that causes select to
 456                  * sometimes wake up even though there is no data available.
 457                  */
 458                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
 459                         len = 0;
 460
 461                 if (len < 0) {
 462                         /* An error has encountered.  Perhaps there is a network problem. */
 463                         snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
 464                                  host, strerror(errno));
 465                         buffer_append(&stderr_buffer, buf, strlen(buf));
 466                         quit_pending = 1;
 467                         return;
 468                 }
 469                 packet_process_incoming(buf, len);
 470         }
 471 }
 472
 473 /* process the characters one by one */
 474 static int
 475 process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
 476 {
 477         char string[1024];
 478         pid_t pid;
 479         int bytes = 0;
 480         u_int i;
 481         u_char ch;
 482         char *s;
 483
 484         for (i = 0; i < len; i++) {
 485                 /* Get one character at a time. */
 486                 ch = buf[i];
 487
 488                 if (escape_pending) {
 489                         /* We have previously seen an escape character. */
 490                         /* Clear the flag now. */
 491                         escape_pending = 0;
 492
 493                         /* Process the escaped character. */
 494                         switch (ch) {
 495                         case '.':
 496                                 /* Terminate the connection. */
 497                                 snprintf(string, sizeof string, "%c.\r\n", escape_char);
 498                                 buffer_append(berr, string, strlen(string));
 499
 500                                 quit_pending = 1;
 501                                 return -1;
 502
 503                         case 'Z' - 64:
 504                                 /* Suspend the program. */
 505                                 /* Print a message to that effect to the user. */
 506                                 snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
 507                                 buffer_append(berr, string, strlen(string));
 508
 509                                 /* Restore terminal modes and suspend. */
 510                                 client_suspend_self(bin, bout, berr);
 511
 512                                 /* We have been continued. */
 513                                 continue;
 514
 515                         case 'R':
 516                                 if (compat20) {
 517                                         if (datafellows & SSH_BUG_NOREKEY)
 518                                                 log("Server does not support re-keying");
 519                                         else
 520                                                 need_rekeying = 1;
 521                                 }
 522                                 continue;
 523
 524                         case '&':
 525                                 /* XXX does not work yet with proto 2 */
 526                                 if (compat20)
 527                                         continue;
 528                                 /*
 529                                  * Detach the program (continue to serve connections,
 530                                  * but put in background and no more new connections).
 531                                  */
 532                                 if (!stdin_eof) {
 533                                         /*
 534                                          * Sending SSH_CMSG_EOF alone does not always appear
 535                                          * to be enough.  So we try to send an EOF character
 536                                          * first.
 537                                          */
 538                                         packet_start(SSH_CMSG_STDIN_DATA);
 539                                         packet_put_string("\004", 1);
 540                                         packet_send();
 541                                         /* Close stdin. */
 542                                         stdin_eof = 1;
 543                                         if (buffer_len(bin) == 0) {
 544                                                 packet_start(SSH_CMSG_EOF);
 545                                                 packet_send();
 546                                         }
 547                                 }
 548                                 /* Restore tty modes. */
 549                                 leave_raw_mode();
 550
 551                                 /* Stop listening for new connections. */
 552                                 channel_close_all();    /* proto1 only XXXX */
 553
 554                                 printf("%c& [backgrounded]\n", escape_char);
 555
 556                                 /* Fork into background. */
 557                                 pid = fork();
 558                                 if (pid < 0) {
 559                                         error("fork: %.100s", strerror(errno));
 560                                         continue;
 561                                 }
 562                                 if (pid != 0) { /* This is the parent. */
 563                                         /* The parent just exits. */
 564                                         exit(0);
 565                                 }
 566                                 /* The child continues serving connections. */
 567                                 continue; /*XXX ? */
 568
 569                         case '?':
 570                                 snprintf(string, sizeof string,
 571 "%c?\r\n\
 572 Supported escape sequences:\r\n\
 573 ~.  - terminate connection\r\n\
 574 ~R  - Request rekey (SSH protocol 2 only)\r\n\
 575 ~^Z - suspend ssh\r\n\
 576 ~#  - list forwarded connections\r\n\
 577 ~&  - background ssh (when waiting for connections to terminate)\r\n\
 578 ~?  - this message\r\n\
 579 ~~  - send the escape character by typing it twice\r\n\
 580 (Note that escapes are only recognized immediately after newline.)\r\n",
 581                                          escape_char);
 582                                 buffer_append(berr, string, strlen(string));
 583                                 continue;
 584
 585                         case '#':
 586                                 snprintf(string, sizeof string, "%c#\r\n", escape_char);
 587                                 buffer_append(berr, string, strlen(string));
 588                                 s = channel_open_message();
 589                                 buffer_append(berr, s, strlen(s));
 590                                 xfree(s);
 591                                 continue;
 592
 593                         default:
 594                                 if (ch != escape_char) {
 595                                         buffer_put_char(bin, escape_char);
 596                                         bytes++;
 597                                 }
 598                                 /* Escaped characters fall through here */
 599                                 break;
 600                         }
 601                 } else {
 602                         /*
 603                          * The previous character was not an escape char. Check if this
 604                          * is an escape.
 605                          */
 606                         if (last_was_cr && ch == escape_char) {
 607                                 /* It is. Set the flag and continue to next character. */
 608                                 escape_pending = 1;
 609                                 continue;
 610                         }
 611                 }
 612
 613                 /*
 614                  * Normal character.  Record whether it was a newline,
 615                  * and append it to the buffer.
 616                  */
 617                 last_was_cr = (ch == '\r' || ch == '\n');
 618                 buffer_put_char(bin, ch);
 619                 bytes++;
 620         }
 621         return bytes;
 622 }
 623
 624 static void
 625 client_process_input(fd_set * readset)
 626 {
 627         int len;
 628         char buf[8192];
 629
 630         /* Read input from stdin. */
 631         if (FD_ISSET(fileno(stdin), readset)) {
 632                 /* Read as much as possible. */
 633                 len = read(fileno(stdin), buf, sizeof(buf));
 634                 if (len < 0 && (errno == EAGAIN || errno == EINTR))
 635                         return;         /* we'll try again later */
 636                 if (len <= 0) {
 637                         /*
 638                          * Received EOF or error.  They are treated
 639                          * similarly, except that an error message is printed
 640                          * if it was an error condition.
 641                          */
 642                         if (len < 0) {
 643                                 snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
 644                                 buffer_append(&stderr_buffer, buf, strlen(buf));
 645                         }
 646                         /* Mark that we have seen EOF. */
 647                         stdin_eof = 1;
 648                         /*
 649                          * Send an EOF message to the server unless there is
 650                          * data in the buffer.  If there is data in the
 651                          * buffer, no message will be sent now.  Code
 652                          * elsewhere will send the EOF when the buffer
 653                          * becomes empty if stdin_eof is set.
 654                          */
 655                         if (buffer_len(&stdin_buffer) == 0) {
 656                                 packet_start(SSH_CMSG_EOF);
 657                                 packet_send();
 658                         }
 659                 } else if (escape_char == SSH_ESCAPECHAR_NONE) {
 660                         /*
 661                          * Normal successful read, and no escape character.
 662                          * Just append the data to buffer.
 663                          */
 664                         buffer_append(&stdin_buffer, buf, len);
 665                 } else {
 666                         /*
 667                          * Normal, successful read.  But we have an escape character
 668                          * and have to process the characters one by one.
 669                          */
 670                         if (process_escapes(&stdin_buffer, &stdout_buffer,
 671                             &stderr_buffer, buf, len) == -1)
 672                                 return;
 673                 }
 674         }
 675 }
 676
 677 static void
 678 client_process_output(fd_set * writeset)
 679 {
 680         int len;
 681         char buf[100];
 682
 683         /* Write buffered output to stdout. */
 684         if (FD_ISSET(fileno(stdout), writeset)) {
 685                 /* Write as much data as possible. */
 686                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
 687                     buffer_len(&stdout_buffer));
 688                 if (len <= 0) {
 689                         if (errno == EINTR || errno == EAGAIN)
 690                                 len = 0;
 691                         else {
 692                                 /*
 693                                  * An error or EOF was encountered.  Put an
 694                                  * error message to stderr buffer.
 695                                  */
 696                                 snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
 697                                 buffer_append(&stderr_buffer, buf, strlen(buf));
 698                                 quit_pending = 1;
 699                                 return;
 700                         }
 701                 }
 702                 /* Consume printed data from the buffer. */
 703                 buffer_consume(&stdout_buffer, len);
 704                 stdout_bytes += len;
 705         }
 706         /* Write buffered output to stderr. */
 707         if (FD_ISSET(fileno(stderr), writeset)) {
 708                 /* Write as much data as possible. */
 709                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
 710                     buffer_len(&stderr_buffer));
 711                 if (len <= 0) {
 712                         if (errno == EINTR || errno == EAGAIN)
 713                                 len = 0;
 714                         else {
 715                                 /* EOF or error, but can't even print error message. */
 716                                 quit_pending = 1;
 717                                 return;
 718                         }
 719                 }
 720                 /* Consume printed characters from the buffer. */
 721                 buffer_consume(&stderr_buffer, len);
 722                 stderr_bytes += len;
 723         }
 724 }
 725
 726 /*
 727  * Get packets from the connection input buffer, and process them as long as
 728  * there are packets available.
 729  *
 730  * Any unknown packets received during the actual
 731  * session cause the session to terminate.  This is
 732  * intended to make debugging easier since no
 733  * confirmations are sent.  Any compatible protocol
 734  * extensions must be negotiated during the
 735  * preparatory phase.
 736  */
 737
 738 static void
 739 client_process_buffered_input_packets(void)
 740 {
 741         dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL);
 742 }
 743
 744 /* scan buf[] for '~' before sending data to the peer */
 745
 746 static int
 747 simple_escape_filter(Channel *c, char *buf, int len)
 748 {
 749         /* XXX we assume c->extended is writeable */
 750         return process_escapes(&c->input, &c->output, &c->extended, buf, len);
 751 }
 752
 753 static void
 754 client_channel_closed(int id, void *arg)
 755 {
 756         if (id != session_ident)
 757                 error("client_channel_closed: id %d != session_ident %d",
 758                     id, session_ident);
 759         channel_cancel_cleanup(id);
 760         session_closed = 1;
 761         if (in_raw_mode())
 762                 leave_raw_mode();
 763 }
 764
 765 /*
 766  * Implements the interactive session with the server.  This is called after
 767  * the user has been authenticated, and a command has been started on the
 768  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
 769  * used as an escape character for terminating or suspending the session.
 770  */
 771
 772 int
 773 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
 774 {
 775         fd_set *readset = NULL, *writeset = NULL;
 776         double start_time, total_time;
 777         int max_fd = 0, max_fd2 = 0, len, rekeying = 0, nalloc = 0;
 778         char buf[100];
 779
 780         debug("Entering interactive session.");
 781
 782         start_time = get_current_time();
 783
 784         /* Initialize variables. */
 785         escape_pending = 0;
 786         last_was_cr = 1;
 787         exit_status = -1;
 788         stdin_eof = 0;
 789         buffer_high = 64 * 1024;
 790         connection_in = packet_get_connection_in();
 791         connection_out = packet_get_connection_out();
 792         max_fd = MAX(connection_in, connection_out);
 793
 794         if (!compat20) {
 795                 /* enable nonblocking unless tty */
 796                 if (!isatty(fileno(stdin)))
 797                         set_nonblock(fileno(stdin));
 798                 if (!isatty(fileno(stdout)))
 799                         set_nonblock(fileno(stdout));
 800                 if (!isatty(fileno(stderr)))
 801                         set_nonblock(fileno(stderr));
 802                 max_fd = MAX(max_fd, fileno(stdin));
 803                 max_fd = MAX(max_fd, fileno(stdout));
 804                 max_fd = MAX(max_fd, fileno(stderr));
 805         }
 806         stdin_bytes = 0;
 807         stdout_bytes = 0;
 808         stderr_bytes = 0;
 809         quit_pending = 0;
 810         escape_char = escape_char_arg;
 811
 812         /* Initialize buffers. */
 813         buffer_init(&stdin_buffer);
 814         buffer_init(&stdout_buffer);
 815         buffer_init(&stderr_buffer);
 816
 817         client_init_dispatch();
 818
 819         /* Set signal handlers to restore non-blocking mode.  */
 820         signal(SIGINT, signal_handler);
 821         signal(SIGQUIT, signal_handler);
 822         signal(SIGTERM, signal_handler);
 823         signal(SIGPIPE, SIG_IGN);
 824         if (have_pty)
 825                 signal(SIGWINCH, window_change_handler);
 826
 827         if (have_pty)
 828                 enter_raw_mode();
 829
 830         if (compat20) {
 831                 session_ident = ssh2_chan_id;
 832                 if (escape_char != SSH_ESCAPECHAR_NONE)
 833                         channel_register_filter(session_ident,
 834                             simple_escape_filter);
 835                 if (session_ident != -1)
 836                         channel_register_cleanup(session_ident,
 837                             client_channel_closed);
 838         } else {
 839                 /* Check if we should immediately send eof on stdin. */
 840                 client_check_initial_eof_on_stdin();
 841         }
 842
 843         /* Main loop of the client for the interactive session mode. */
 844         while (!quit_pending) {
 845
 846                 /* Process buffered packets sent by the server. */
 847                 client_process_buffered_input_packets();
 848
 849                 if (compat20 && session_closed && !channel_still_open())
 850                         break;
 851
 852                 rekeying = (xxx_kex != NULL && !xxx_kex->done);
 853
 854                 if (rekeying) {
 855                         debug("rekeying in progress");
 856                 } else {
 857                         /*
 858                          * Make packets of buffered stdin data, and buffer
 859                          * them for sending to the server.
 860                          */
 861                         if (!compat20)
 862                                 client_make_packets_from_stdin_data();
 863
 864                         /*
 865                          * Make packets from buffered channel data, and
 866                          * enqueue them for sending to the server.
 867                          */
 868                         if (packet_not_very_much_data_to_write())
 869                                 channel_output_poll();
 870
 871                         /*
 872                          * Check if the window size has changed, and buffer a
 873                          * message about it to the server if so.
 874                          */
 875                         client_check_window_change();
 876
 877                         if (quit_pending)
 878                                 break;
 879                 }
 880                 /*
 881                  * Wait until we have something to do (something becomes
 882                  * available on one of the descriptors).
 883                  */
 884                 max_fd2 = max_fd;
 885                 client_wait_until_can_do_something(&readset, &writeset,
 886                     &max_fd2, &nalloc, rekeying);
 887
 888                 if (quit_pending)
 889                         break;
 890
 891                 /* Do channel operations unless rekeying in progress. */
 892                 if (!rekeying) {
 893                         channel_after_select(readset, writeset);
 894
 895                         if (need_rekeying) {
 896                                 debug("user requests rekeying");
 897                                 xxx_kex->done = 0;
 898                                 kex_send_kexinit(xxx_kex);
 899                                 need_rekeying = 0;
 900                         }
 901                 }
 902
 903                 /* Buffer input from the connection.  */
 904                 client_process_net_input(readset);
 905
 906                 if (quit_pending)
 907                         break;
 908
 909                 if (!compat20) {
 910                         /* Buffer data from stdin */
 911                         client_process_input(readset);
 912                         /*
 913                          * Process output to stdout and stderr.  Output to
 914                          * the connection is processed elsewhere (above).
 915                          */
 916                         client_process_output(writeset);
 917                 }
 918
 919                 /* Send as much buffered packet data as possible to the sender. */
 920                 if (FD_ISSET(connection_out, writeset))
 921                         packet_write_poll();
 922         }
 923         if (readset)
 924                 xfree(readset);
 925         if (writeset)
 926                 xfree(writeset);
 927
 928         /* Terminate the session. */
 929
 930         /* Stop watching for window change. */
 931         if (have_pty)
 932                 signal(SIGWINCH, SIG_DFL);
 933
 934         channel_free_all();
 935
 936         if (have_pty)
 937                 leave_raw_mode();
 938
 939         /* restore blocking io */
 940         if (!isatty(fileno(stdin)))
 941                 unset_nonblock(fileno(stdin));
 942         if (!isatty(fileno(stdout)))
 943                 unset_nonblock(fileno(stdout));
 944         if (!isatty(fileno(stderr)))
 945                 unset_nonblock(fileno(stderr));
 946
 947         if (received_signal) {
 948                 if (in_non_blocking_mode)       /* XXX */
 949                         leave_non_blocking();
 950                 fatal("Killed by signal %d.", received_signal);
 951         }
 952
 953         /*
 954          * In interactive mode (with pseudo tty) display a message indicating
 955          * that the connection has been closed.
 956          */
 957         if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
 958                 snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
 959                 buffer_append(&stderr_buffer, buf, strlen(buf));
 960         }
 961
 962         /* Output any buffered data for stdout. */
 963         while (buffer_len(&stdout_buffer) > 0) {
 964                 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
 965                     buffer_len(&stdout_buffer));
 966                 if (len <= 0) {
 967                         error("Write failed flushing stdout buffer.");
 968                         break;
 969                 }
 970                 buffer_consume(&stdout_buffer, len);
 971                 stdout_bytes += len;
 972         }
 973
 974         /* Output any buffered data for stderr. */
 975         while (buffer_len(&stderr_buffer) > 0) {
 976                 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
 977                     buffer_len(&stderr_buffer));
 978                 if (len <= 0) {
 979                         error("Write failed flushing stderr buffer.");
 980                         break;
 981                 }
 982                 buffer_consume(&stderr_buffer, len);
 983                 stderr_bytes += len;
 984         }
 985
 986         /* Clear and free any buffers. */
 987         memset(buf, 0, sizeof(buf));
 988         buffer_free(&stdin_buffer);
 989         buffer_free(&stdout_buffer);
 990         buffer_free(&stderr_buffer);
 991
 992         /* Report bytes transferred, and transfer rates. */
 993         total_time = get_current_time() - start_time;
 994         debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
 995               stdin_bytes, stdout_bytes, stderr_bytes, total_time);
 996         if (total_time > 0)
 997                 debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
 998                       stdin_bytes / total_time, stdout_bytes / total_time,
 999                       stderr_bytes / total_time);
1000
1001         /* Return the exit status of the program. */
1002         debug("Exit status %d", exit_status);
1003         return exit_status;
1004 }
1005
1006 /*********/
1007
1008 static void
1009 client_input_stdout_data(int type, int plen, void *ctxt)
1010 {
1011         u_int data_len;
1012         char *data = packet_get_string(&data_len);
1013         packet_integrity_check(plen, 4 + data_len, type);
1014         buffer_append(&stdout_buffer, data, data_len);
1015         memset(data, 0, data_len);
1016         xfree(data);
1017 }
1018 static void
1019 client_input_stderr_data(int type, int plen, void *ctxt)
1020 {
1021         u_int data_len;
1022         char *data = packet_get_string(&data_len);
1023         packet_integrity_check(plen, 4 + data_len, type);
1024         buffer_append(&stderr_buffer, data, data_len);
1025         memset(data, 0, data_len);
1026         xfree(data);
1027 }
1028 static void
1029 client_input_exit_status(int type, int plen, void *ctxt)
1030 {
1031         packet_integrity_check(plen, 4, type);
1032         exit_status = packet_get_int();
1033         /* Acknowledge the exit. */
1034         packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1035         packet_send();
1036         /*
1037          * Must wait for packet to be sent since we are
1038          * exiting the loop.
1039          */
1040         packet_write_wait();
1041         /* Flag that we want to exit. */
1042         quit_pending = 1;
1043 }
1044
1045 static Channel *
1046 client_request_forwarded_tcpip(const char *request_type, int rchan)
1047 {
1048         Channel* c = NULL;
1049         char *listen_address, *originator_address;
1050         int listen_port, originator_port;
1051         int sock;
1052
1053         /* Get rest of the packet */
1054         listen_address = packet_get_string(NULL);
1055         listen_port = packet_get_int();
1056         originator_address = packet_get_string(NULL);
1057         originator_port = packet_get_int();
1058         packet_done();
1059
1060         debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1061             listen_address, listen_port, originator_address, originator_port);
1062
1063         sock = channel_connect_by_listen_address(listen_port);
1064         if (sock < 0) {
1065                 xfree(originator_address);
1066                 xfree(listen_address);
1067                 return NULL;
1068         }
1069         c = channel_new("forwarded-tcpip",
1070             SSH_CHANNEL_CONNECTING, sock, sock, -1,
1071             CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1072             xstrdup(originator_address), 1);
1073         if (c == NULL) {
1074                 error("client_request_forwarded_tcpip: channel_new failed");
1075                 close(sock);
1076         }
1077         xfree(originator_address);
1078         xfree(listen_address);
1079         return c;
1080 }
1081
1082 static Channel*
1083 client_request_x11(const char *request_type, int rchan)
1084 {
1085         Channel *c = NULL;
1086         char *originator;
1087         int originator_port;
1088         int sock;
1089
1090         if (!options.forward_x11) {
1091                 error("Warning: ssh server tried X11 forwarding.");
1092                 error("Warning: this is probably a break in attempt by a malicious server.");
1093                 return NULL;
1094         }
1095         originator = packet_get_string(NULL);
1096         if (datafellows & SSH_BUG_X11FWD) {
1097                 debug2("buggy server: x11 request w/o originator_port");
1098                 originator_port = 0;
1099         } else {
1100                 originator_port = packet_get_int();
1101         }
1102         packet_done();
1103         /* XXX check permission */
1104         debug("client_request_x11: request from %s %d", originator,
1105             originator_port);
1106         xfree(originator);
1107         sock = x11_connect_display();
1108         if (sock < 0)
1109                 return NULL;
1110         c = channel_new("x11",
1111             SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1112             CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0,
1113             xstrdup("x11"), 1);
1114         if (c == NULL) {
1115                 error("client_request_x11: channel_new failed");
1116                 close(sock);
1117         }
1118         c->force_drain = 1;
1119         return c;
1120 }
1121
1122 static Channel*
1123 client_request_agent(const char *request_type, int rchan)
1124 {
1125         Channel *c = NULL;
1126         int sock;
1127
1128         if (!options.forward_agent) {
1129                 error("Warning: ssh server tried agent forwarding.");
1130                 error("Warning: this is probably a break in attempt by a malicious server.");
1131                 return NULL;
1132         }
1133         sock =  ssh_get_authentication_socket();
1134         if (sock < 0)
1135                 return NULL;
1136         c = channel_new("authentication agent connection",
1137             SSH_CHANNEL_OPEN, sock, sock, -1,
1138             CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1139             xstrdup("authentication agent connection"), 1);
1140         if (c == NULL) {
1141                 error("client_request_agent: channel_new failed");
1142                 close(sock);
1143         }
1144         c->force_drain = 1;
1145         return c;
1146 }
1147
1148 /* XXXX move to generic input handler */
1149 static void
1150 client_input_channel_open(int type, int plen, void *ctxt)
1151 {
1152         Channel *c = NULL;
1153         char *ctype;
1154         u_int len;
1155         int rchan;
1156         int rmaxpack;
1157         int rwindow;
1158
1159         ctype = packet_get_string(&len);
1160         rchan = packet_get_int();
1161         rwindow = packet_get_int();
1162         rmaxpack = packet_get_int();
1163
1164         debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1165             ctype, rchan, rwindow, rmaxpack);
1166
1167         if (strcmp(ctype, "forwarded-tcpip") == 0) {
1168                 c = client_request_forwarded_tcpip(ctype, rchan);
1169         } else if (strcmp(ctype, "x11") == 0) {
1170                 c = client_request_x11(ctype, rchan);
1171         } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1172                 c = client_request_agent(ctype, rchan);
1173         }
1174 /* XXX duplicate : */
1175         if (c != NULL) {
1176                 debug("confirm %s", ctype);
1177                 c->remote_id = rchan;
1178                 c->remote_window = rwindow;
1179                 c->remote_maxpacket = rmaxpack;
1180                 if (c->type != SSH_CHANNEL_CONNECTING) {
1181                         packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1182                         packet_put_int(c->remote_id);
1183                         packet_put_int(c->self);
1184                         packet_put_int(c->local_window);
1185                         packet_put_int(c->local_maxpacket);
1186                         packet_send();
1187                 }
1188         } else {
1189                 debug("failure %s", ctype);
1190                 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1191                 packet_put_int(rchan);
1192                 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1193                 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1194                         packet_put_cstring("open failed");
1195                         packet_put_cstring("");
1196                 }
1197                 packet_send();
1198         }
1199         xfree(ctype);
1200 }
1201 static void
1202 client_input_channel_req(int type, int plen, void *ctxt)
1203 {
1204         Channel *c = NULL;
1205         int id, reply, success = 0;
1206         char *rtype;
1207
1208         id = packet_get_int();
1209         rtype = packet_get_string(NULL);
1210         reply = packet_get_char();
1211
1212         debug("client_input_channel_req: channel %d rtype %s reply %d",
1213             id, rtype, reply);
1214
1215         if (session_ident == -1) {
1216                 error("client_input_channel_req: no channel %d", session_ident);
1217         } else if (id != session_ident) {
1218                 error("client_input_channel_req: channel %d: wrong channel: %d",
1219                     session_ident, id);
1220         }
1221         c = channel_lookup(id);
1222         if (c == NULL) {
1223                 error("client_input_channel_req: channel %d: unknown channel", id);
1224         } else if (strcmp(rtype, "exit-status") == 0) {
1225                 success = 1;
1226                 exit_status = packet_get_int();
1227                 packet_done();
1228         }
1229         if (reply) {
1230                 packet_start(success ?
1231                     SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1232                 packet_put_int(c->remote_id);
1233                 packet_send();
1234         }
1235         xfree(rtype);
1236 }
1237
1238 static void
1239 client_init_dispatch_20(void)
1240 {
1241         dispatch_init(&dispatch_protocol_error);
1242         dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1243         dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1244         dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1245         dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1246         dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1247         dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1248         dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1249         dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1250         dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1251
1252         /* rekeying */
1253         dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1254 }
1255 static void
1256 client_init_dispatch_13(void)
1257 {
1258         dispatch_init(NULL);
1259         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1260         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1261         dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1262         dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1263         dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1264         dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1265         dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
1266         dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
1267         dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1268
1269         dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1270             &auth_input_open_request : &deny_input_open);
1271         dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
1272             &x11_input_open : &deny_input_open);
1273 }
1274 static void
1275 client_init_dispatch_15(void)
1276 {
1277         client_init_dispatch_13();
1278         dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1279         dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
1280 }
1281 static void
1282 client_init_dispatch(void)
1283 {
1284         if (compat20)
1285                 client_init_dispatch_20();
1286         else if (compat13)
1287                 client_init_dispatch_13();
1288         else
1289                 client_init_dispatch_15();
1290 }