Annotation of src/usr.bin/ssh/clientloop.c, Revision 1.116
1.1 deraadt 1: /*
1.12 deraadt 2: * Author: Tatu Ylonen <ylo@cs.hut.fi>
3: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4: * All rights reserved
1.33 deraadt 5: * The main loop for the interactive session (client side).
1.20 markus 6: *
1.33 deraadt 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.
1.20 markus 35: *
36: *
1.33 deraadt 37: * SSH2 support added by Markus Friedl.
1.78 markus 38: * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
1.20 markus 39: *
1.33 deraadt 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.
1.12 deraadt 59: */
1.1 deraadt 60:
61: #include "includes.h"
1.116 ! dtucker 62: RCSID("$OpenBSD: clientloop.c,v 1.115 2003/09/23 20:41:11 markus Exp $");
1.1 deraadt 63:
1.45 markus 64: #include "ssh.h"
65: #include "ssh1.h"
66: #include "ssh2.h"
1.1 deraadt 67: #include "xmalloc.h"
68: #include "packet.h"
69: #include "buffer.h"
1.15 markus 70: #include "compat.h"
1.74 markus 71: #include "channels.h"
1.15 markus 72: #include "dispatch.h"
1.30 markus 73: #include "buffer.h"
74: #include "bufaux.h"
1.40 markus 75: #include "key.h"
1.54 markus 76: #include "kex.h"
1.45 markus 77: #include "log.h"
78: #include "readconf.h"
79: #include "clientloop.h"
1.40 markus 80: #include "authfd.h"
1.45 markus 81: #include "atomicio.h"
1.62 stevesk 82: #include "sshtty.h"
1.63 markus 83: #include "misc.h"
1.97 jakob 84: #include "readpass.h"
1.39 markus 85:
86: /* import options */
87: extern Options options;
88:
1.1 deraadt 89: /* Flag indicating that stdin should be redirected from /dev/null. */
90: extern int stdin_null_flag;
91:
1.116 ! dtucker 92: /* Flag indicating that no shell has been requested */
! 93: extern int no_shell_flag;
! 94:
1.13 markus 95: /*
96: * Name of the host we are connecting to. This is the name given on the
97: * command line, or the HostName specified for the user-supplied name in a
98: * configuration file.
99: */
1.1 deraadt 100: extern char *host;
101:
1.13 markus 102: /*
103: * Flag to indicate that we have received a window change signal which has
104: * not yet been processed. This will cause a message indicating the new
105: * window size to be sent to the server a little later. This is volatile
106: * because this is updated in a signal handler.
107: */
1.88 markus 108: static volatile sig_atomic_t received_window_change_signal = 0;
109: static volatile sig_atomic_t received_signal = 0;
1.1 deraadt 110:
111: /* Flag indicating whether the user\'s terminal is in non-blocking mode. */
112: static int in_non_blocking_mode = 0;
113:
114: /* Common data for the client loop code. */
1.31 markus 115: static int quit_pending; /* Set to non-zero to quit the client loop. */
116: static int escape_char; /* Escape character. */
1.11 markus 117: static int escape_pending; /* Last character was the escape character */
118: static int last_was_cr; /* Last character was a newline. */
119: static int exit_status; /* Used to store the exit status of the command. */
120: static int stdin_eof; /* EOF has been encountered on standard error. */
121: static Buffer stdin_buffer; /* Buffer for stdin data. */
122: static Buffer stdout_buffer; /* Buffer for stdout data. */
123: static Buffer stderr_buffer; /* Buffer for stderr data. */
1.42 markus 124: static u_long stdin_bytes, stdout_bytes, stderr_bytes;
125: static u_int buffer_high;/* Soft max buffer size. */
1.11 markus 126: static int connection_in; /* Connection to server (input). */
127: static int connection_out; /* Connection to server (output). */
1.56 markus 128: static int need_rekeying; /* Set to non-zero if rekeying is requested. */
1.60 markus 129: static int session_closed = 0; /* In SSH2: login session closed. */
1.1 deraadt 130:
1.77 itojun 131: static void client_init_dispatch(void);
1.16 markus 132: int session_ident = -1;
133:
1.54 markus 134: /*XXX*/
135: extern Kex *xxx_kex;
136:
1.1 deraadt 137: /* Restores stdin to blocking mode. */
138:
1.77 itojun 139: static void
1.49 itojun 140: leave_non_blocking(void)
1.1 deraadt 141: {
1.11 markus 142: if (in_non_blocking_mode) {
143: (void) fcntl(fileno(stdin), F_SETFL, 0);
144: in_non_blocking_mode = 0;
145: }
1.1 deraadt 146: }
147:
1.11 markus 148: /* Puts stdin terminal in non-blocking mode. */
149:
1.77 itojun 150: static void
1.49 itojun 151: enter_non_blocking(void)
1.1 deraadt 152: {
1.11 markus 153: in_non_blocking_mode = 1;
154: (void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
1.1 deraadt 155: }
156:
1.13 markus 157: /*
158: * Signal handler for the window change signal (SIGWINCH). This just sets a
159: * flag indicating that the window has changed.
160: */
1.1 deraadt 161:
1.77 itojun 162: static void
1.11 markus 163: window_change_handler(int sig)
1.1 deraadt 164: {
1.11 markus 165: received_window_change_signal = 1;
166: signal(SIGWINCH, window_change_handler);
1.1 deraadt 167: }
168:
1.13 markus 169: /*
170: * Signal handler for signals that cause the program to terminate. These
171: * signals must be trapped to restore terminal modes.
172: */
1.1 deraadt 173:
1.77 itojun 174: static void
1.11 markus 175: signal_handler(int sig)
1.1 deraadt 176: {
1.75 markus 177: received_signal = sig;
178: quit_pending = 1;
1.1 deraadt 179: }
180:
1.13 markus 181: /*
182: * Returns current time in seconds from Jan 1, 1970 with the maximum
183: * available resolution.
184: */
1.1 deraadt 185:
1.77 itojun 186: static double
1.49 itojun 187: get_current_time(void)
1.1 deraadt 188: {
1.11 markus 189: struct timeval tv;
190: gettimeofday(&tv, NULL);
191: return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
1.1 deraadt 192: }
193:
1.13 markus 194: /*
195: * This is called when the interactive is entered. This checks if there is
196: * an EOF coming on stdin. We must check this explicitly, as select() does
197: * not appear to wake up when redirecting from /dev/null.
198: */
1.1 deraadt 199:
1.77 itojun 200: static void
1.49 itojun 201: client_check_initial_eof_on_stdin(void)
1.1 deraadt 202: {
1.11 markus 203: int len;
204: char buf[1];
1.1 deraadt 205:
1.13 markus 206: /*
207: * If standard input is to be "redirected from /dev/null", we simply
208: * mark that we have seen an EOF and send an EOF message to the
209: * server. Otherwise, we try to read a single character; it appears
210: * that for some files, such /dev/null, select() never wakes up for
211: * read for this descriptor, which means that we never get EOF. This
212: * way we will get the EOF if stdin comes from /dev/null or similar.
213: */
1.11 markus 214: if (stdin_null_flag) {
215: /* Fake EOF on stdin. */
216: debug("Sending eof.");
217: stdin_eof = 1;
218: packet_start(SSH_CMSG_EOF);
219: packet_send();
220: } else {
221: enter_non_blocking();
222:
223: /* Check for immediate EOF on stdin. */
224: len = read(fileno(stdin), buf, 1);
225: if (len == 0) {
1.13 markus 226: /* EOF. Record that we have seen it and send EOF to server. */
1.11 markus 227: debug("Sending eof.");
228: stdin_eof = 1;
229: packet_start(SSH_CMSG_EOF);
230: packet_send();
231: } else if (len > 0) {
1.13 markus 232: /*
233: * Got data. We must store the data in the buffer,
234: * and also process it as an escape character if
235: * appropriate.
236: */
1.42 markus 237: if ((u_char) buf[0] == escape_char)
1.11 markus 238: escape_pending = 1;
1.52 markus 239: else
1.11 markus 240: buffer_append(&stdin_buffer, buf, 1);
241: }
242: leave_non_blocking();
243: }
1.1 deraadt 244: }
245:
246:
1.13 markus 247: /*
248: * Make packets from buffered stdin data, and buffer them for sending to the
249: * connection.
250: */
1.1 deraadt 251:
1.77 itojun 252: static void
1.49 itojun 253: client_make_packets_from_stdin_data(void)
1.1 deraadt 254: {
1.42 markus 255: u_int len;
1.1 deraadt 256:
1.11 markus 257: /* Send buffered stdin data to the server. */
258: while (buffer_len(&stdin_buffer) > 0 &&
1.90 deraadt 259: packet_not_very_much_data_to_write()) {
1.11 markus 260: len = buffer_len(&stdin_buffer);
261: /* Keep the packets at reasonable size. */
262: if (len > packet_get_maxsize())
263: len = packet_get_maxsize();
264: packet_start(SSH_CMSG_STDIN_DATA);
265: packet_put_string(buffer_ptr(&stdin_buffer), len);
266: packet_send();
267: buffer_consume(&stdin_buffer, len);
1.52 markus 268: stdin_bytes += len;
1.11 markus 269: /* If we have a pending EOF, send it now. */
270: if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
271: packet_start(SSH_CMSG_EOF);
272: packet_send();
273: }
1.1 deraadt 274: }
275: }
276:
1.13 markus 277: /*
278: * Checks if the client window has changed, and sends a packet about it to
279: * the server if so. The actual change is detected elsewhere (by a software
280: * interrupt on Unix); this just checks the flag and sends a message if
281: * appropriate.
282: */
1.1 deraadt 283:
1.77 itojun 284: static void
1.49 itojun 285: client_check_window_change(void)
1.1 deraadt 286: {
1.16 markus 287: struct winsize ws;
288:
289: if (! received_window_change_signal)
290: return;
291: /** XXX race */
292: received_window_change_signal = 0;
293:
294: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
295: return;
296:
1.37 markus 297: debug2("client_check_window_change: changed");
1.16 markus 298:
299: if (compat20) {
300: channel_request_start(session_ident, "window-change", 0);
301: packet_put_int(ws.ws_col);
302: packet_put_int(ws.ws_row);
303: packet_put_int(ws.ws_xpixel);
304: packet_put_int(ws.ws_ypixel);
305: packet_send();
306: } else {
307: packet_start(SSH_CMSG_WINDOW_SIZE);
308: packet_put_int(ws.ws_row);
309: packet_put_int(ws.ws_col);
310: packet_put_int(ws.ws_xpixel);
311: packet_put_int(ws.ws_ypixel);
312: packet_send();
1.1 deraadt 313: }
314: }
315:
1.13 markus 316: /*
317: * Waits until the client can do something (some data becomes available on
318: * one of the file descriptors).
319: */
1.1 deraadt 320:
1.77 itojun 321: static void
1.46 markus 322: client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
1.81 markus 323: int *maxfdp, int *nallocp, int rekeying)
1.11 markus 324: {
1.46 markus 325: /* Add any selections by the channel mechanism. */
1.81 markus 326: channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
1.11 markus 327:
1.16 markus 328: if (!compat20) {
1.17 markus 329: /* Read from the connection, unless our buffers are full. */
1.16 markus 330: if (buffer_len(&stdout_buffer) < buffer_high &&
331: buffer_len(&stderr_buffer) < buffer_high &&
332: channel_not_very_much_buffered_data())
1.46 markus 333: FD_SET(connection_in, *readsetp);
1.17 markus 334: /*
335: * Read from stdin, unless we have seen EOF or have very much
336: * buffered data to send to the server.
337: */
338: if (!stdin_eof && packet_not_very_much_data_to_write())
1.46 markus 339: FD_SET(fileno(stdin), *readsetp);
1.17 markus 340:
341: /* Select stdout/stderr if have data in buffer. */
342: if (buffer_len(&stdout_buffer) > 0)
1.46 markus 343: FD_SET(fileno(stdout), *writesetp);
1.17 markus 344: if (buffer_len(&stderr_buffer) > 0)
1.46 markus 345: FD_SET(fileno(stderr), *writesetp);
1.16 markus 346: } else {
1.71 markus 347: /* channel_prepare_select could have closed the last channel */
1.84 markus 348: if (session_closed && !channel_still_open() &&
349: !packet_have_data_to_write()) {
350: /* clear mask since we did not call select() */
1.87 markus 351: memset(*readsetp, 0, *nallocp);
352: memset(*writesetp, 0, *nallocp);
1.84 markus 353: return;
1.71 markus 354: } else {
355: FD_SET(connection_in, *readsetp);
356: }
1.16 markus 357: }
1.11 markus 358:
359: /* Select server connection if have data to write to the server. */
360: if (packet_have_data_to_write())
1.46 markus 361: FD_SET(connection_out, *writesetp);
1.11 markus 362:
1.13 markus 363: /*
364: * Wait for something to happen. This will suspend the process until
365: * some selected descriptor can be read, written, or has some other
366: * event pending. Note: if you want to implement SSH_MSG_IGNORE
367: * messages to fool traffic analysis, this might be the place to do
368: * it: just have a random timeout for the select, and send a random
369: * SSH_MSG_IGNORE packet when the timeout expires.
370: */
1.11 markus 371:
1.46 markus 372: if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) {
1.11 markus 373: char buf[100];
1.51 markus 374:
375: /*
376: * We have to clear the select masks, because we return.
377: * We have to return, because the mainloop checks for the flags
378: * set by the signal handlers.
379: */
1.87 markus 380: memset(*readsetp, 0, *nallocp);
381: memset(*writesetp, 0, *nallocp);
1.50 deraadt 382:
1.11 markus 383: if (errno == EINTR)
384: return;
385: /* Note: we might still have data in the buffers. */
386: snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
387: buffer_append(&stderr_buffer, buf, strlen(buf));
388: quit_pending = 1;
389: }
390: }
391:
1.77 itojun 392: static void
1.31 markus 393: client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
1.1 deraadt 394: {
1.11 markus 395: struct winsize oldws, newws;
396:
397: /* Flush stdout and stderr buffers. */
1.31 markus 398: if (buffer_len(bout) > 0)
1.112 deraadt 399: atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
1.31 markus 400: if (buffer_len(berr) > 0)
1.112 deraadt 401: atomicio(vwrite, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
1.11 markus 402:
403: leave_raw_mode();
404:
1.13 markus 405: /*
406: * Free (and clear) the buffer to reduce the amount of data that gets
407: * written to swap.
408: */
1.31 markus 409: buffer_free(bin);
410: buffer_free(bout);
411: buffer_free(berr);
1.11 markus 412:
413: /* Save old window size. */
414: ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
415:
416: /* Send the suspend signal to the program itself. */
417: kill(getpid(), SIGTSTP);
418:
419: /* Check if the window size has changed. */
420: if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 &&
421: (oldws.ws_row != newws.ws_row ||
1.90 deraadt 422: oldws.ws_col != newws.ws_col ||
423: oldws.ws_xpixel != newws.ws_xpixel ||
424: oldws.ws_ypixel != newws.ws_ypixel))
1.11 markus 425: received_window_change_signal = 1;
426:
427: /* OK, we have been continued by the user. Reinitialize buffers. */
1.31 markus 428: buffer_init(bin);
429: buffer_init(bout);
430: buffer_init(berr);
1.11 markus 431:
432: enter_raw_mode();
433: }
434:
1.77 itojun 435: static void
1.17 markus 436: client_process_net_input(fd_set * readset)
1.11 markus 437: {
1.17 markus 438: int len;
439: char buf[8192];
1.11 markus 440:
1.13 markus 441: /*
442: * Read input from the server, and add any such data to the buffer of
443: * the packet subsystem.
444: */
1.11 markus 445: if (FD_ISSET(connection_in, readset)) {
446: /* Read as much as possible. */
447: len = read(connection_in, buf, sizeof(buf));
448: if (len == 0) {
449: /* Received EOF. The remote host has closed the connection. */
450: snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
451: host);
1.1 deraadt 452: buffer_append(&stderr_buffer, buf, strlen(buf));
453: quit_pending = 1;
454: return;
1.11 markus 455: }
1.13 markus 456: /*
457: * There is a kernel bug on Solaris that causes select to
458: * sometimes wake up even though there is no data available.
459: */
1.53 millert 460: if (len < 0 && (errno == EAGAIN || errno == EINTR))
1.11 markus 461: len = 0;
462:
463: if (len < 0) {
464: /* An error has encountered. Perhaps there is a network problem. */
465: snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
466: host, strerror(errno));
467: buffer_append(&stderr_buffer, buf, strlen(buf));
468: quit_pending = 1;
469: return;
470: }
471: packet_process_incoming(buf, len);
472: }
1.17 markus 473: }
1.16 markus 474:
1.97 jakob 475: static void
1.99 markus 476: process_cmdline(void)
1.97 jakob 477: {
478: void (*handler)(int);
479: char *s, *cmd;
480: u_short fwd_port, fwd_host_port;
481: char buf[1024], sfwd_port[6], sfwd_host_port[6];
482: int local = 0;
483:
484: leave_raw_mode();
1.101 markus 485: handler = signal(SIGINT, SIG_IGN);
1.99 markus 486: cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
1.97 jakob 487: if (s == NULL)
488: goto out;
489: while (*s && isspace(*s))
490: s++;
491: if (*s == 0)
492: goto out;
493: if (strlen(s) < 2 || s[0] != '-' || !(s[1] == 'L' || s[1] == 'R')) {
1.109 itojun 494: logit("Invalid command.");
1.97 jakob 495: goto out;
496: }
497: if (s[1] == 'L')
498: local = 1;
499: if (!local && !compat20) {
1.109 itojun 500: logit("Not supported for SSH protocol version 1.");
1.97 jakob 501: goto out;
502: }
503: s += 2;
504: while (*s && isspace(*s))
505: s++;
506:
507: if (sscanf(s, "%5[0-9]:%255[^:]:%5[0-9]",
508: sfwd_port, buf, sfwd_host_port) != 3 &&
509: sscanf(s, "%5[0-9]/%255[^/]/%5[0-9]",
510: sfwd_port, buf, sfwd_host_port) != 3) {
1.109 itojun 511: logit("Bad forwarding specification.");
1.97 jakob 512: goto out;
513: }
514: if ((fwd_port = a2port(sfwd_port)) == 0 ||
515: (fwd_host_port = a2port(sfwd_host_port)) == 0) {
1.109 itojun 516: logit("Bad forwarding port(s).");
1.97 jakob 517: goto out;
518: }
519: if (local) {
1.99 markus 520: if (channel_setup_local_fwd_listener(fwd_port, buf,
521: fwd_host_port, options.gateway_ports) < 0) {
1.109 itojun 522: logit("Port forwarding failed.");
1.97 jakob 523: goto out;
524: }
525: } else
526: channel_request_remote_forwarding(fwd_port, buf,
527: fwd_host_port);
1.109 itojun 528: logit("Forwarding port.");
1.97 jakob 529: out:
530: signal(SIGINT, handler);
531: enter_raw_mode();
532: if (cmd)
533: xfree(cmd);
534: }
535:
1.31 markus 536: /* process the characters one by one */
1.77 itojun 537: static int
1.31 markus 538: process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
539: {
1.32 markus 540: char string[1024];
1.31 markus 541: pid_t pid;
542: int bytes = 0;
1.42 markus 543: u_int i;
544: u_char ch;
1.31 markus 545: char *s;
546:
547: for (i = 0; i < len; i++) {
548: /* Get one character at a time. */
549: ch = buf[i];
550:
551: if (escape_pending) {
552: /* We have previously seen an escape character. */
553: /* Clear the flag now. */
554: escape_pending = 0;
555:
556: /* Process the escaped character. */
557: switch (ch) {
558: case '.':
559: /* Terminate the connection. */
1.32 markus 560: snprintf(string, sizeof string, "%c.\r\n", escape_char);
561: buffer_append(berr, string, strlen(string));
1.31 markus 562:
563: quit_pending = 1;
564: return -1;
565:
566: case 'Z' - 64:
567: /* Suspend the program. */
568: /* Print a message to that effect to the user. */
1.32 markus 569: snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
570: buffer_append(berr, string, strlen(string));
1.31 markus 571:
572: /* Restore terminal modes and suspend. */
573: client_suspend_self(bin, bout, berr);
574:
575: /* We have been continued. */
576: continue;
577:
1.111 markus 578: case 'B':
579: if (compat20) {
580: snprintf(string, sizeof string,
581: "%cB\r\n", escape_char);
582: buffer_append(berr, string,
583: strlen(string));
584: channel_request_start(session_ident,
585: "break", 0);
586: packet_put_int(1000);
587: packet_send();
588: }
589: continue;
590:
1.54 markus 591: case 'R':
1.59 markus 592: if (compat20) {
593: if (datafellows & SSH_BUG_NOREKEY)
1.109 itojun 594: logit("Server does not support re-keying");
1.59 markus 595: else
596: need_rekeying = 1;
597: }
1.54 markus 598: continue;
599:
1.31 markus 600: case '&':
601: /*
602: * Detach the program (continue to serve connections,
603: * but put in background and no more new connections).
604: */
605: /* Restore tty modes. */
606: leave_raw_mode();
607:
608: /* Stop listening for new connections. */
1.86 markus 609: channel_stop_listening();
1.31 markus 610:
1.86 markus 611: snprintf(string, sizeof string,
612: "%c& [backgrounded]\n", escape_char);
613: buffer_append(berr, string, strlen(string));
1.31 markus 614:
615: /* Fork into background. */
616: pid = fork();
617: if (pid < 0) {
618: error("fork: %.100s", strerror(errno));
619: continue;
620: }
621: if (pid != 0) { /* This is the parent. */
622: /* The parent just exits. */
623: exit(0);
624: }
625: /* The child continues serving connections. */
1.86 markus 626: if (compat20) {
627: buffer_append(bin, "\004", 1);
628: /* fake EOF on stdin */
629: return -1;
630: } else if (!stdin_eof) {
631: /*
632: * Sending SSH_CMSG_EOF alone does not always appear
633: * to be enough. So we try to send an EOF character
634: * first.
635: */
636: packet_start(SSH_CMSG_STDIN_DATA);
637: packet_put_string("\004", 1);
638: packet_send();
639: /* Close stdin. */
640: stdin_eof = 1;
641: if (buffer_len(bin) == 0) {
642: packet_start(SSH_CMSG_EOF);
643: packet_send();
644: }
645: }
646: continue;
1.31 markus 647:
648: case '?':
1.32 markus 649: snprintf(string, sizeof string,
1.31 markus 650: "%c?\r\n\
651: Supported escape sequences:\r\n\
1.104 stevesk 652: %c. - terminate connection\r\n\
1.111 markus 653: %cB - send a BREAK to the remote system\r\n\
1.104 stevesk 654: %cC - open a command line\r\n\
655: %cR - Request rekey (SSH protocol 2 only)\r\n\
656: %c^Z - suspend ssh\r\n\
657: %c# - list forwarded connections\r\n\
658: %c& - background ssh (when waiting for connections to terminate)\r\n\
659: %c? - this message\r\n\
660: %c%c - send the escape character by typing it twice\r\n\
1.31 markus 661: (Note that escapes are only recognized immediately after newline.)\r\n",
1.104 stevesk 662: escape_char, escape_char, escape_char, escape_char,
663: escape_char, escape_char, escape_char, escape_char,
1.111 markus 664: escape_char, escape_char, escape_char);
1.32 markus 665: buffer_append(berr, string, strlen(string));
1.31 markus 666: continue;
667:
668: case '#':
1.32 markus 669: snprintf(string, sizeof string, "%c#\r\n", escape_char);
670: buffer_append(berr, string, strlen(string));
1.31 markus 671: s = channel_open_message();
672: buffer_append(berr, s, strlen(s));
673: xfree(s);
1.97 jakob 674: continue;
675:
676: case 'C':
1.99 markus 677: process_cmdline();
1.31 markus 678: continue;
679:
680: default:
681: if (ch != escape_char) {
682: buffer_put_char(bin, escape_char);
683: bytes++;
684: }
685: /* Escaped characters fall through here */
686: break;
687: }
688: } else {
689: /*
690: * The previous character was not an escape char. Check if this
691: * is an escape.
692: */
693: if (last_was_cr && ch == escape_char) {
694: /* It is. Set the flag and continue to next character. */
695: escape_pending = 1;
696: continue;
697: }
698: }
699:
700: /*
701: * Normal character. Record whether it was a newline,
702: * and append it to the buffer.
703: */
704: last_was_cr = (ch == '\r' || ch == '\n');
705: buffer_put_char(bin, ch);
706: bytes++;
707: }
708: return bytes;
709: }
710:
1.77 itojun 711: static void
1.17 markus 712: client_process_input(fd_set * readset)
713: {
1.21 deraadt 714: int len;
1.31 markus 715: char buf[8192];
1.16 markus 716:
1.11 markus 717: /* Read input from stdin. */
718: if (FD_ISSET(fileno(stdin), readset)) {
719: /* Read as much as possible. */
720: len = read(fileno(stdin), buf, sizeof(buf));
1.64 markus 721: if (len < 0 && (errno == EAGAIN || errno == EINTR))
722: return; /* we'll try again later */
1.11 markus 723: if (len <= 0) {
1.13 markus 724: /*
725: * Received EOF or error. They are treated
726: * similarly, except that an error message is printed
727: * if it was an error condition.
728: */
1.11 markus 729: if (len < 0) {
730: snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
731: buffer_append(&stderr_buffer, buf, strlen(buf));
732: }
733: /* Mark that we have seen EOF. */
734: stdin_eof = 1;
1.13 markus 735: /*
736: * Send an EOF message to the server unless there is
737: * data in the buffer. If there is data in the
738: * buffer, no message will be sent now. Code
739: * elsewhere will send the EOF when the buffer
740: * becomes empty if stdin_eof is set.
741: */
1.11 markus 742: if (buffer_len(&stdin_buffer) == 0) {
1.1 deraadt 743: packet_start(SSH_CMSG_EOF);
744: packet_send();
1.11 markus 745: }
1.72 stevesk 746: } else if (escape_char == SSH_ESCAPECHAR_NONE) {
1.13 markus 747: /*
748: * Normal successful read, and no escape character.
749: * Just append the data to buffer.
750: */
1.11 markus 751: buffer_append(&stdin_buffer, buf, len);
752: } else {
1.13 markus 753: /*
754: * Normal, successful read. But we have an escape character
755: * and have to process the characters one by one.
756: */
1.52 markus 757: if (process_escapes(&stdin_buffer, &stdout_buffer,
758: &stderr_buffer, buf, len) == -1)
1.31 markus 759: return;
1.11 markus 760: }
761: }
762: }
763:
1.77 itojun 764: static void
1.11 markus 765: client_process_output(fd_set * writeset)
766: {
767: int len;
768: char buf[100];
1.1 deraadt 769:
1.11 markus 770: /* Write buffered output to stdout. */
771: if (FD_ISSET(fileno(stdout), writeset)) {
772: /* Write as much data as possible. */
773: len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1.14 deraadt 774: buffer_len(&stdout_buffer));
1.11 markus 775: if (len <= 0) {
1.64 markus 776: if (errno == EINTR || errno == EAGAIN)
1.11 markus 777: len = 0;
778: else {
1.13 markus 779: /*
780: * An error or EOF was encountered. Put an
781: * error message to stderr buffer.
782: */
1.11 markus 783: snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
784: buffer_append(&stderr_buffer, buf, strlen(buf));
785: quit_pending = 1;
786: return;
787: }
788: }
789: /* Consume printed data from the buffer. */
790: buffer_consume(&stdout_buffer, len);
1.57 markus 791: stdout_bytes += len;
1.11 markus 792: }
793: /* Write buffered output to stderr. */
794: if (FD_ISSET(fileno(stderr), writeset)) {
795: /* Write as much data as possible. */
796: len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1.14 deraadt 797: buffer_len(&stderr_buffer));
1.11 markus 798: if (len <= 0) {
1.64 markus 799: if (errno == EINTR || errno == EAGAIN)
1.11 markus 800: len = 0;
801: else {
1.13 markus 802: /* EOF or error, but can't even print error message. */
1.11 markus 803: quit_pending = 1;
804: return;
805: }
806: }
807: /* Consume printed characters from the buffer. */
808: buffer_consume(&stderr_buffer, len);
1.57 markus 809: stderr_bytes += len;
1.11 markus 810: }
1.1 deraadt 811: }
812:
1.13 markus 813: /*
1.15 markus 814: * Get packets from the connection input buffer, and process them as long as
815: * there are packets available.
816: *
817: * Any unknown packets received during the actual
818: * session cause the session to terminate. This is
819: * intended to make debugging easier since no
820: * confirmations are sent. Any compatible protocol
821: * extensions must be negotiated during the
822: * preparatory phase.
823: */
824:
1.77 itojun 825: static void
1.49 itojun 826: client_process_buffered_input_packets(void)
1.15 markus 827: {
1.54 markus 828: dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL);
1.15 markus 829: }
830:
1.31 markus 831: /* scan buf[] for '~' before sending data to the peer */
1.30 markus 832:
1.77 itojun 833: static int
1.31 markus 834: simple_escape_filter(Channel *c, char *buf, int len)
1.30 markus 835: {
1.31 markus 836: /* XXX we assume c->extended is writeable */
837: return process_escapes(&c->input, &c->output, &c->extended, buf, len);
1.30 markus 838: }
839:
1.77 itojun 840: static void
1.60 markus 841: client_channel_closed(int id, void *arg)
842: {
843: if (id != session_ident)
844: error("client_channel_closed: id %d != session_ident %d",
845: id, session_ident);
1.83 markus 846: channel_cancel_cleanup(id);
1.60 markus 847: session_closed = 1;
1.113 markus 848: leave_raw_mode();
1.60 markus 849: }
850:
1.15 markus 851: /*
1.13 markus 852: * Implements the interactive session with the server. This is called after
853: * the user has been authenticated, and a command has been started on the
1.72 stevesk 854: * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character
855: * used as an escape character for terminating or suspending the session.
1.13 markus 856: */
1.1 deraadt 857:
1.20 markus 858: int
1.30 markus 859: client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1.1 deraadt 860: {
1.46 markus 861: fd_set *readset = NULL, *writeset = NULL;
1.11 markus 862: double start_time, total_time;
1.81 markus 863: int max_fd = 0, max_fd2 = 0, len, rekeying = 0, nalloc = 0;
1.11 markus 864: char buf[100];
865:
866: debug("Entering interactive session.");
867:
868: start_time = get_current_time();
869:
870: /* Initialize variables. */
871: escape_pending = 0;
872: last_was_cr = 1;
873: exit_status = -1;
874: stdin_eof = 0;
875: buffer_high = 64 * 1024;
876: connection_in = packet_get_connection_in();
877: connection_out = packet_get_connection_out();
1.46 markus 878: max_fd = MAX(connection_in, connection_out);
879:
880: if (!compat20) {
1.63 markus 881: /* enable nonblocking unless tty */
882: if (!isatty(fileno(stdin)))
883: set_nonblock(fileno(stdin));
884: if (!isatty(fileno(stdout)))
885: set_nonblock(fileno(stdout));
886: if (!isatty(fileno(stderr)))
887: set_nonblock(fileno(stderr));
1.46 markus 888: max_fd = MAX(max_fd, fileno(stdin));
889: max_fd = MAX(max_fd, fileno(stdout));
890: max_fd = MAX(max_fd, fileno(stderr));
891: }
1.11 markus 892: stdin_bytes = 0;
893: stdout_bytes = 0;
894: stderr_bytes = 0;
895: quit_pending = 0;
896: escape_char = escape_char_arg;
897:
898: /* Initialize buffers. */
899: buffer_init(&stdin_buffer);
900: buffer_init(&stdout_buffer);
901: buffer_init(&stderr_buffer);
902:
1.15 markus 903: client_init_dispatch();
904:
1.105 markus 905: /*
906: * Set signal handlers, (e.g. to restore non-blocking mode)
907: * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
908: */
909: if (signal(SIGINT, SIG_IGN) != SIG_IGN)
910: signal(SIGINT, signal_handler);
911: if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
912: signal(SIGQUIT, signal_handler);
913: if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
914: signal(SIGTERM, signal_handler);
1.11 markus 915: if (have_pty)
916: signal(SIGWINCH, window_change_handler);
917:
918: if (have_pty)
919: enter_raw_mode();
920:
1.48 markus 921: if (compat20) {
922: session_ident = ssh2_chan_id;
1.72 stevesk 923: if (escape_char != SSH_ESCAPECHAR_NONE)
1.48 markus 924: channel_register_filter(session_ident,
925: simple_escape_filter);
1.60 markus 926: if (session_ident != -1)
927: channel_register_cleanup(session_ident,
928: client_channel_closed);
1.48 markus 929: } else {
930: /* Check if we should immediately send eof on stdin. */
1.16 markus 931: client_check_initial_eof_on_stdin();
1.48 markus 932: }
1.30 markus 933:
1.11 markus 934: /* Main loop of the client for the interactive session mode. */
935: while (!quit_pending) {
936:
1.13 markus 937: /* Process buffered packets sent by the server. */
1.11 markus 938: client_process_buffered_input_packets();
939:
1.60 markus 940: if (compat20 && session_closed && !channel_still_open())
941: break;
942:
1.56 markus 943: rekeying = (xxx_kex != NULL && !xxx_kex->done);
1.16 markus 944:
1.56 markus 945: if (rekeying) {
946: debug("rekeying in progress");
947: } else {
948: /*
949: * Make packets of buffered stdin data, and buffer
950: * them for sending to the server.
951: */
952: if (!compat20)
953: client_make_packets_from_stdin_data();
1.11 markus 954:
1.56 markus 955: /*
956: * Make packets from buffered channel data, and
957: * enqueue them for sending to the server.
958: */
959: if (packet_not_very_much_data_to_write())
960: channel_output_poll();
1.11 markus 961:
1.56 markus 962: /*
963: * Check if the window size has changed, and buffer a
964: * message about it to the server if so.
965: */
966: client_check_window_change();
1.11 markus 967:
1.56 markus 968: if (quit_pending)
969: break;
970: }
1.13 markus 971: /*
972: * Wait until we have something to do (something becomes
973: * available on one of the descriptors).
974: */
1.81 markus 975: max_fd2 = max_fd;
1.56 markus 976: client_wait_until_can_do_something(&readset, &writeset,
1.81 markus 977: &max_fd2, &nalloc, rekeying);
1.11 markus 978:
979: if (quit_pending)
980: break;
981:
1.56 markus 982: /* Do channel operations unless rekeying in progress. */
983: if (!rekeying) {
984: channel_after_select(readset, writeset);
1.108 markus 985: if (need_rekeying || packet_need_rekeying()) {
986: debug("need rekeying");
1.56 markus 987: xxx_kex->done = 0;
988: kex_send_kexinit(xxx_kex);
989: need_rekeying = 0;
990: }
991: }
1.11 markus 992:
1.17 markus 993: /* Buffer input from the connection. */
1.46 markus 994: client_process_net_input(readset);
1.17 markus 995:
996: if (quit_pending)
997: break;
1.11 markus 998:
1.17 markus 999: if (!compat20) {
1000: /* Buffer data from stdin */
1.46 markus 1001: client_process_input(readset);
1.17 markus 1002: /*
1003: * Process output to stdout and stderr. Output to
1004: * the connection is processed elsewhere (above).
1005: */
1.46 markus 1006: client_process_output(writeset);
1.17 markus 1007: }
1.11 markus 1008:
1.13 markus 1009: /* Send as much buffered packet data as possible to the sender. */
1.46 markus 1010: if (FD_ISSET(connection_out, writeset))
1.11 markus 1011: packet_write_poll();
1012: }
1.46 markus 1013: if (readset)
1014: xfree(readset);
1015: if (writeset)
1016: xfree(writeset);
1.11 markus 1017:
1018: /* Terminate the session. */
1019:
1020: /* Stop watching for window change. */
1021: if (have_pty)
1022: signal(SIGWINCH, SIG_DFL);
1023:
1.76 markus 1024: channel_free_all();
1.11 markus 1025:
1.75 markus 1026: if (have_pty)
1027: leave_raw_mode();
1028:
1029: /* restore blocking io */
1030: if (!isatty(fileno(stdin)))
1031: unset_nonblock(fileno(stdin));
1032: if (!isatty(fileno(stdout)))
1033: unset_nonblock(fileno(stdout));
1034: if (!isatty(fileno(stderr)))
1035: unset_nonblock(fileno(stderr));
1.116 ! dtucker 1036:
! 1037: /*
! 1038: * If there was no shell or command requested, there will be no remote
! 1039: * exit status to be returned. In that case, clear error code if the
! 1040: * connection was deliberately terminated at this end.
! 1041: */
! 1042: if (no_shell_flag && received_signal == SIGTERM) {
! 1043: received_signal = 0;
! 1044: exit_status = 0;
! 1045: }
1.75 markus 1046:
1.113 markus 1047: if (received_signal)
1.89 itojun 1048: fatal("Killed by signal %d.", (int) received_signal);
1.75 markus 1049:
1.13 markus 1050: /*
1051: * In interactive mode (with pseudo tty) display a message indicating
1052: * that the connection has been closed.
1053: */
1.11 markus 1054: if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1055: snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
1056: buffer_append(&stderr_buffer, buf, strlen(buf));
1057: }
1.70 markus 1058:
1.11 markus 1059: /* Output any buffered data for stdout. */
1.70 markus 1060: while (buffer_len(&stdout_buffer) > 0) {
1061: len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1.14 deraadt 1062: buffer_len(&stdout_buffer));
1.70 markus 1063: if (len <= 0) {
1.11 markus 1064: error("Write failed flushing stdout buffer.");
1.70 markus 1065: break;
1066: }
1.11 markus 1067: buffer_consume(&stdout_buffer, len);
1.57 markus 1068: stdout_bytes += len;
1.11 markus 1069: }
1070:
1071: /* Output any buffered data for stderr. */
1.70 markus 1072: while (buffer_len(&stderr_buffer) > 0) {
1073: len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1.14 deraadt 1074: buffer_len(&stderr_buffer));
1.70 markus 1075: if (len <= 0) {
1.11 markus 1076: error("Write failed flushing stderr buffer.");
1.70 markus 1077: break;
1078: }
1.11 markus 1079: buffer_consume(&stderr_buffer, len);
1.57 markus 1080: stderr_bytes += len;
1.11 markus 1081: }
1082:
1083: /* Clear and free any buffers. */
1084: memset(buf, 0, sizeof(buf));
1085: buffer_free(&stdin_buffer);
1086: buffer_free(&stdout_buffer);
1087: buffer_free(&stderr_buffer);
1088:
1089: /* Report bytes transferred, and transfer rates. */
1090: total_time = get_current_time() - start_time;
1091: debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
1.90 deraadt 1092: stdin_bytes, stdout_bytes, stderr_bytes, total_time);
1.11 markus 1093: if (total_time > 0)
1094: debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
1.90 deraadt 1095: stdin_bytes / total_time, stdout_bytes / total_time,
1096: stderr_bytes / total_time);
1.11 markus 1097:
1098: /* Return the exit status of the program. */
1099: debug("Exit status %d", exit_status);
1100: return exit_status;
1.15 markus 1101: }
1102:
1103: /*********/
1104:
1.77 itojun 1105: static void
1.94 markus 1106: client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1.15 markus 1107: {
1.42 markus 1108: u_int data_len;
1.15 markus 1109: char *data = packet_get_string(&data_len);
1.93 markus 1110: packet_check_eom();
1.15 markus 1111: buffer_append(&stdout_buffer, data, data_len);
1112: memset(data, 0, data_len);
1113: xfree(data);
1114: }
1.77 itojun 1115: static void
1.94 markus 1116: client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1.15 markus 1117: {
1.42 markus 1118: u_int data_len;
1.15 markus 1119: char *data = packet_get_string(&data_len);
1.93 markus 1120: packet_check_eom();
1.15 markus 1121: buffer_append(&stderr_buffer, data, data_len);
1122: memset(data, 0, data_len);
1123: xfree(data);
1124: }
1.77 itojun 1125: static void
1.94 markus 1126: client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1.15 markus 1127: {
1128: exit_status = packet_get_int();
1.93 markus 1129: packet_check_eom();
1.15 markus 1130: /* Acknowledge the exit. */
1131: packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1132: packet_send();
1133: /*
1134: * Must wait for packet to be sent since we are
1135: * exiting the loop.
1136: */
1137: packet_write_wait();
1138: /* Flag that we want to exit. */
1139: quit_pending = 1;
1140: }
1.115 markus 1141: static void
1142: client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1143: {
1144: Channel *c = NULL;
1145: int remote_id, sock;
1146:
1147: /* Read the remote channel number from the message. */
1148: remote_id = packet_get_int();
1149: packet_check_eom();
1150:
1151: /*
1152: * Get a connection to the local authentication agent (this may again
1153: * get forwarded).
1154: */
1155: sock = ssh_get_authentication_socket();
1156:
1157: /*
1158: * If we could not connect the agent, send an error message back to
1159: * the server. This should never happen unless the agent dies,
1160: * because authentication forwarding is only enabled if we have an
1161: * agent.
1162: */
1163: if (sock >= 0) {
1164: c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1165: -1, 0, 0, 0, "authentication agent connection", 1);
1166: c->remote_id = remote_id;
1167: c->force_drain = 1;
1168: }
1169: if (c == NULL) {
1170: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1171: packet_put_int(remote_id);
1172: } else {
1173: /* Send a confirmation to the remote host. */
1174: debug("Forwarding authentication connection.");
1175: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1176: packet_put_int(remote_id);
1177: packet_put_int(c->self);
1178: }
1179: packet_send();
1180: }
1.15 markus 1181:
1.77 itojun 1182: static Channel *
1.40 markus 1183: client_request_forwarded_tcpip(const char *request_type, int rchan)
1184: {
1.103 deraadt 1185: Channel *c = NULL;
1.40 markus 1186: char *listen_address, *originator_address;
1187: int listen_port, originator_port;
1.67 markus 1188: int sock;
1.40 markus 1189:
1190: /* Get rest of the packet */
1191: listen_address = packet_get_string(NULL);
1192: listen_port = packet_get_int();
1193: originator_address = packet_get_string(NULL);
1194: originator_port = packet_get_int();
1.93 markus 1195: packet_check_eom();
1.40 markus 1196:
1197: debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1198: listen_address, listen_port, originator_address, originator_port);
1199:
1.80 stevesk 1200: sock = channel_connect_by_listen_address(listen_port);
1.67 markus 1201: if (sock < 0) {
1202: xfree(originator_address);
1203: xfree(listen_address);
1204: return NULL;
1205: }
1206: c = channel_new("forwarded-tcpip",
1207: SSH_CHANNEL_CONNECTING, sock, sock, -1,
1208: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1.110 markus 1209: originator_address, 1);
1.40 markus 1210: xfree(originator_address);
1211: xfree(listen_address);
1212: return c;
1213: }
1214:
1.103 deraadt 1215: static Channel *
1.40 markus 1216: client_request_x11(const char *request_type, int rchan)
1217: {
1218: Channel *c = NULL;
1219: char *originator;
1220: int originator_port;
1.67 markus 1221: int sock;
1.40 markus 1222:
1223: if (!options.forward_x11) {
1224: error("Warning: ssh server tried X11 forwarding.");
1225: error("Warning: this is probably a break in attempt by a malicious server.");
1226: return NULL;
1227: }
1228: originator = packet_get_string(NULL);
1229: if (datafellows & SSH_BUG_X11FWD) {
1230: debug2("buggy server: x11 request w/o originator_port");
1231: originator_port = 0;
1232: } else {
1233: originator_port = packet_get_int();
1234: }
1.93 markus 1235: packet_check_eom();
1.40 markus 1236: /* XXX check permission */
1.47 markus 1237: debug("client_request_x11: request from %s %d", originator,
1238: originator_port);
1.67 markus 1239: xfree(originator);
1.40 markus 1240: sock = x11_connect_display();
1.67 markus 1241: if (sock < 0)
1242: return NULL;
1243: c = channel_new("x11",
1244: SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1.110 markus 1245: CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1.82 markus 1246: c->force_drain = 1;
1.40 markus 1247: return c;
1248: }
1249:
1.103 deraadt 1250: static Channel *
1.40 markus 1251: client_request_agent(const char *request_type, int rchan)
1252: {
1253: Channel *c = NULL;
1.67 markus 1254: int sock;
1.40 markus 1255:
1256: if (!options.forward_agent) {
1257: error("Warning: ssh server tried agent forwarding.");
1258: error("Warning: this is probably a break in attempt by a malicious server.");
1259: return NULL;
1260: }
1261: sock = ssh_get_authentication_socket();
1.67 markus 1262: if (sock < 0)
1263: return NULL;
1264: c = channel_new("authentication agent connection",
1265: SSH_CHANNEL_OPEN, sock, sock, -1,
1266: CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1.110 markus 1267: "authentication agent connection", 1);
1.82 markus 1268: c->force_drain = 1;
1.40 markus 1269: return c;
1270: }
1271:
1.22 markus 1272: /* XXXX move to generic input handler */
1.77 itojun 1273: static void
1.94 markus 1274: client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1.22 markus 1275: {
1276: Channel *c = NULL;
1277: char *ctype;
1278: int rchan;
1.102 markus 1279: u_int rmaxpack, rwindow, len;
1.22 markus 1280:
1281: ctype = packet_get_string(&len);
1282: rchan = packet_get_int();
1283: rwindow = packet_get_int();
1284: rmaxpack = packet_get_int();
1285:
1.24 markus 1286: debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1.22 markus 1287: ctype, rchan, rwindow, rmaxpack);
1288:
1.40 markus 1289: if (strcmp(ctype, "forwarded-tcpip") == 0) {
1290: c = client_request_forwarded_tcpip(ctype, rchan);
1291: } else if (strcmp(ctype, "x11") == 0) {
1292: c = client_request_x11(ctype, rchan);
1293: } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1294: c = client_request_agent(ctype, rchan);
1.22 markus 1295: }
1296: /* XXX duplicate : */
1297: if (c != NULL) {
1298: debug("confirm %s", ctype);
1299: c->remote_id = rchan;
1300: c->remote_window = rwindow;
1301: c->remote_maxpacket = rmaxpack;
1.69 markus 1302: if (c->type != SSH_CHANNEL_CONNECTING) {
1303: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1304: packet_put_int(c->remote_id);
1305: packet_put_int(c->self);
1306: packet_put_int(c->local_window);
1307: packet_put_int(c->local_maxpacket);
1308: packet_send();
1309: }
1.22 markus 1310: } else {
1311: debug("failure %s", ctype);
1312: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1313: packet_put_int(rchan);
1314: packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1.66 markus 1315: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.69 markus 1316: packet_put_cstring("open failed");
1.66 markus 1317: packet_put_cstring("");
1318: }
1.22 markus 1319: packet_send();
1320: }
1321: xfree(ctype);
1322: }
1.77 itojun 1323: static void
1.94 markus 1324: client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1.48 markus 1325: {
1326: Channel *c = NULL;
1327: int id, reply, success = 0;
1328: char *rtype;
1329:
1330: id = packet_get_int();
1331: rtype = packet_get_string(NULL);
1332: reply = packet_get_char();
1333:
1334: debug("client_input_channel_req: channel %d rtype %s reply %d",
1335: id, rtype, reply);
1336:
1337: if (session_ident == -1) {
1338: error("client_input_channel_req: no channel %d", session_ident);
1339: } else if (id != session_ident) {
1340: error("client_input_channel_req: channel %d: wrong channel: %d",
1341: session_ident, id);
1342: }
1343: c = channel_lookup(id);
1344: if (c == NULL) {
1345: error("client_input_channel_req: channel %d: unknown channel", id);
1346: } else if (strcmp(rtype, "exit-status") == 0) {
1347: success = 1;
1348: exit_status = packet_get_int();
1.93 markus 1349: packet_check_eom();
1.48 markus 1350: }
1351: if (reply) {
1352: packet_start(success ?
1353: SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1354: packet_put_int(c->remote_id);
1355: packet_send();
1356: }
1357: xfree(rtype);
1358: }
1.95 markus 1359: static void
1360: client_input_global_request(int type, u_int32_t seq, void *ctxt)
1361: {
1362: char *rtype;
1363: int want_reply;
1364: int success = 0;
1365:
1366: rtype = packet_get_string(NULL);
1367: want_reply = packet_get_char();
1368: debug("client_input_global_request: rtype %s want_reply %d", rtype, want_reply);
1369: if (want_reply) {
1370: packet_start(success ?
1371: SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1372: packet_send();
1373: packet_write_wait();
1374: }
1375: xfree(rtype);
1376: }
1.22 markus 1377:
1.77 itojun 1378: static void
1.49 itojun 1379: client_init_dispatch_20(void)
1.16 markus 1380: {
1.55 markus 1381: dispatch_init(&dispatch_protocol_error);
1.100 markus 1382:
1.16 markus 1383: dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1384: dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1385: dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1386: dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1.22 markus 1387: dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1.16 markus 1388: dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1389: dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1.48 markus 1390: dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1.16 markus 1391: dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1.95 markus 1392: dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1.55 markus 1393:
1394: /* rekeying */
1395: dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1.100 markus 1396:
1397: /* global request reply messages */
1398: dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
1399: dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1.16 markus 1400: }
1.77 itojun 1401: static void
1.49 itojun 1402: client_init_dispatch_13(void)
1.15 markus 1403: {
1404: dispatch_init(NULL);
1405: dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1406: dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1407: dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1408: dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1409: dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1410: dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1411: dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
1412: dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
1413: dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1.39 markus 1414:
1415: dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1.115 markus 1416: &client_input_agent_open : &deny_input_open);
1.39 markus 1417: dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
1418: &x11_input_open : &deny_input_open);
1.15 markus 1419: }
1.77 itojun 1420: static void
1.49 itojun 1421: client_init_dispatch_15(void)
1.15 markus 1422: {
1423: client_init_dispatch_13();
1424: dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1425: dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
1426: }
1.79 stevesk 1427: static void
1.49 itojun 1428: client_init_dispatch(void)
1.15 markus 1429: {
1.16 markus 1430: if (compat20)
1431: client_init_dispatch_20();
1432: else if (compat13)
1.15 markus 1433: client_init_dispatch_13();
1434: else
1435: client_init_dispatch_15();
1.113 markus 1436: }
1437:
1438: /* client specific fatal cleanup */
1439: void
1.114 markus 1440: cleanup_exit(int i)
1.113 markus 1441: {
1442: leave_raw_mode();
1443: leave_non_blocking();
1.114 markus 1444: _exit(i);
1.1 deraadt 1445: }
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