Annotation of src/usr.bin/ssh/clientloop.c, Revision 1.113
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"
1.113 ! markus 62: RCSID("$OpenBSD: clientloop.c,v 1.112 2003/06/28 16:23:06 deraadt 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:
1.13 markus 92: /*
93: * Name of the host we are connecting to. This is the name given on the
94: * command line, or the HostName specified for the user-supplied name in a
95: * configuration file.
96: */
1.1 deraadt 97: extern char *host;
98:
1.13 markus 99: /*
100: * Flag to indicate that we have received a window change signal which has
101: * not yet been processed. This will cause a message indicating the new
102: * window size to be sent to the server a little later. This is volatile
103: * because this is updated in a signal handler.
104: */
1.88 markus 105: static volatile sig_atomic_t received_window_change_signal = 0;
106: static volatile sig_atomic_t received_signal = 0;
1.1 deraadt 107:
108: /* Flag indicating whether the user\'s terminal is in non-blocking mode. */
109: static int in_non_blocking_mode = 0;
110:
111: /* Common data for the client loop code. */
1.31 markus 112: static int quit_pending; /* Set to non-zero to quit the client loop. */
113: static int escape_char; /* Escape character. */
1.11 markus 114: static int escape_pending; /* Last character was the escape character */
115: static int last_was_cr; /* Last character was a newline. */
116: static int exit_status; /* Used to store the exit status of the command. */
117: static int stdin_eof; /* EOF has been encountered on standard error. */
118: static Buffer stdin_buffer; /* Buffer for stdin data. */
119: static Buffer stdout_buffer; /* Buffer for stdout data. */
120: static Buffer stderr_buffer; /* Buffer for stderr data. */
1.42 markus 121: static u_long stdin_bytes, stdout_bytes, stderr_bytes;
122: static u_int buffer_high;/* Soft max buffer size. */
1.11 markus 123: static int connection_in; /* Connection to server (input). */
124: static int connection_out; /* Connection to server (output). */
1.56 markus 125: static int need_rekeying; /* Set to non-zero if rekeying is requested. */
1.60 markus 126: static int session_closed = 0; /* In SSH2: login session closed. */
1.1 deraadt 127:
1.77 itojun 128: static void client_init_dispatch(void);
1.16 markus 129: int session_ident = -1;
130:
1.54 markus 131: /*XXX*/
132: extern Kex *xxx_kex;
133:
1.1 deraadt 134: /* Restores stdin to blocking mode. */
135:
1.77 itojun 136: static void
1.49 itojun 137: leave_non_blocking(void)
1.1 deraadt 138: {
1.11 markus 139: if (in_non_blocking_mode) {
140: (void) fcntl(fileno(stdin), F_SETFL, 0);
141: in_non_blocking_mode = 0;
142: }
1.1 deraadt 143: }
144:
1.11 markus 145: /* Puts stdin terminal in non-blocking mode. */
146:
1.77 itojun 147: static void
1.49 itojun 148: enter_non_blocking(void)
1.1 deraadt 149: {
1.11 markus 150: in_non_blocking_mode = 1;
151: (void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
1.1 deraadt 152: }
153:
1.13 markus 154: /*
155: * Signal handler for the window change signal (SIGWINCH). This just sets a
156: * flag indicating that the window has changed.
157: */
1.1 deraadt 158:
1.77 itojun 159: static void
1.11 markus 160: window_change_handler(int sig)
1.1 deraadt 161: {
1.11 markus 162: received_window_change_signal = 1;
163: signal(SIGWINCH, window_change_handler);
1.1 deraadt 164: }
165:
1.13 markus 166: /*
167: * Signal handler for signals that cause the program to terminate. These
168: * signals must be trapped to restore terminal modes.
169: */
1.1 deraadt 170:
1.77 itojun 171: static void
1.11 markus 172: signal_handler(int sig)
1.1 deraadt 173: {
1.75 markus 174: received_signal = sig;
175: quit_pending = 1;
1.1 deraadt 176: }
177:
1.13 markus 178: /*
179: * Returns current time in seconds from Jan 1, 1970 with the maximum
180: * available resolution.
181: */
1.1 deraadt 182:
1.77 itojun 183: static double
1.49 itojun 184: get_current_time(void)
1.1 deraadt 185: {
1.11 markus 186: struct timeval tv;
187: gettimeofday(&tv, NULL);
188: return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
1.1 deraadt 189: }
190:
1.13 markus 191: /*
192: * This is called when the interactive is entered. This checks if there is
193: * an EOF coming on stdin. We must check this explicitly, as select() does
194: * not appear to wake up when redirecting from /dev/null.
195: */
1.1 deraadt 196:
1.77 itojun 197: static void
1.49 itojun 198: client_check_initial_eof_on_stdin(void)
1.1 deraadt 199: {
1.11 markus 200: int len;
201: char buf[1];
1.1 deraadt 202:
1.13 markus 203: /*
204: * If standard input is to be "redirected from /dev/null", we simply
205: * mark that we have seen an EOF and send an EOF message to the
206: * server. Otherwise, we try to read a single character; it appears
207: * that for some files, such /dev/null, select() never wakes up for
208: * read for this descriptor, which means that we never get EOF. This
209: * way we will get the EOF if stdin comes from /dev/null or similar.
210: */
1.11 markus 211: if (stdin_null_flag) {
212: /* Fake EOF on stdin. */
213: debug("Sending eof.");
214: stdin_eof = 1;
215: packet_start(SSH_CMSG_EOF);
216: packet_send();
217: } else {
218: enter_non_blocking();
219:
220: /* Check for immediate EOF on stdin. */
221: len = read(fileno(stdin), buf, 1);
222: if (len == 0) {
1.13 markus 223: /* EOF. Record that we have seen it and send EOF to server. */
1.11 markus 224: debug("Sending eof.");
225: stdin_eof = 1;
226: packet_start(SSH_CMSG_EOF);
227: packet_send();
228: } else if (len > 0) {
1.13 markus 229: /*
230: * Got data. We must store the data in the buffer,
231: * and also process it as an escape character if
232: * appropriate.
233: */
1.42 markus 234: if ((u_char) buf[0] == escape_char)
1.11 markus 235: escape_pending = 1;
1.52 markus 236: else
1.11 markus 237: buffer_append(&stdin_buffer, buf, 1);
238: }
239: leave_non_blocking();
240: }
1.1 deraadt 241: }
242:
243:
1.13 markus 244: /*
245: * Make packets from buffered stdin data, and buffer them for sending to the
246: * connection.
247: */
1.1 deraadt 248:
1.77 itojun 249: static void
1.49 itojun 250: client_make_packets_from_stdin_data(void)
1.1 deraadt 251: {
1.42 markus 252: u_int len;
1.1 deraadt 253:
1.11 markus 254: /* Send buffered stdin data to the server. */
255: while (buffer_len(&stdin_buffer) > 0 &&
1.90 deraadt 256: packet_not_very_much_data_to_write()) {
1.11 markus 257: len = buffer_len(&stdin_buffer);
258: /* Keep the packets at reasonable size. */
259: if (len > packet_get_maxsize())
260: len = packet_get_maxsize();
261: packet_start(SSH_CMSG_STDIN_DATA);
262: packet_put_string(buffer_ptr(&stdin_buffer), len);
263: packet_send();
264: buffer_consume(&stdin_buffer, len);
1.52 markus 265: stdin_bytes += len;
1.11 markus 266: /* If we have a pending EOF, send it now. */
267: if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
268: packet_start(SSH_CMSG_EOF);
269: packet_send();
270: }
1.1 deraadt 271: }
272: }
273:
1.13 markus 274: /*
275: * Checks if the client window has changed, and sends a packet about it to
276: * the server if so. The actual change is detected elsewhere (by a software
277: * interrupt on Unix); this just checks the flag and sends a message if
278: * appropriate.
279: */
1.1 deraadt 280:
1.77 itojun 281: static void
1.49 itojun 282: client_check_window_change(void)
1.1 deraadt 283: {
1.16 markus 284: struct winsize ws;
285:
286: if (! received_window_change_signal)
287: return;
288: /** XXX race */
289: received_window_change_signal = 0;
290:
291: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
292: return;
293:
1.37 markus 294: debug2("client_check_window_change: changed");
1.16 markus 295:
296: if (compat20) {
297: channel_request_start(session_ident, "window-change", 0);
298: packet_put_int(ws.ws_col);
299: packet_put_int(ws.ws_row);
300: packet_put_int(ws.ws_xpixel);
301: packet_put_int(ws.ws_ypixel);
302: packet_send();
303: } else {
304: packet_start(SSH_CMSG_WINDOW_SIZE);
305: packet_put_int(ws.ws_row);
306: packet_put_int(ws.ws_col);
307: packet_put_int(ws.ws_xpixel);
308: packet_put_int(ws.ws_ypixel);
309: packet_send();
1.1 deraadt 310: }
311: }
312:
1.13 markus 313: /*
314: * Waits until the client can do something (some data becomes available on
315: * one of the file descriptors).
316: */
1.1 deraadt 317:
1.77 itojun 318: static void
1.46 markus 319: client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
1.81 markus 320: int *maxfdp, int *nallocp, int rekeying)
1.11 markus 321: {
1.46 markus 322: /* Add any selections by the channel mechanism. */
1.81 markus 323: channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
1.11 markus 324:
1.16 markus 325: if (!compat20) {
1.17 markus 326: /* Read from the connection, unless our buffers are full. */
1.16 markus 327: if (buffer_len(&stdout_buffer) < buffer_high &&
328: buffer_len(&stderr_buffer) < buffer_high &&
329: channel_not_very_much_buffered_data())
1.46 markus 330: FD_SET(connection_in, *readsetp);
1.17 markus 331: /*
332: * Read from stdin, unless we have seen EOF or have very much
333: * buffered data to send to the server.
334: */
335: if (!stdin_eof && packet_not_very_much_data_to_write())
1.46 markus 336: FD_SET(fileno(stdin), *readsetp);
1.17 markus 337:
338: /* Select stdout/stderr if have data in buffer. */
339: if (buffer_len(&stdout_buffer) > 0)
1.46 markus 340: FD_SET(fileno(stdout), *writesetp);
1.17 markus 341: if (buffer_len(&stderr_buffer) > 0)
1.46 markus 342: FD_SET(fileno(stderr), *writesetp);
1.16 markus 343: } else {
1.71 markus 344: /* channel_prepare_select could have closed the last channel */
1.84 markus 345: if (session_closed && !channel_still_open() &&
346: !packet_have_data_to_write()) {
347: /* clear mask since we did not call select() */
1.87 markus 348: memset(*readsetp, 0, *nallocp);
349: memset(*writesetp, 0, *nallocp);
1.84 markus 350: return;
1.71 markus 351: } else {
352: FD_SET(connection_in, *readsetp);
353: }
1.16 markus 354: }
1.11 markus 355:
356: /* Select server connection if have data to write to the server. */
357: if (packet_have_data_to_write())
1.46 markus 358: FD_SET(connection_out, *writesetp);
1.11 markus 359:
1.13 markus 360: /*
361: * Wait for something to happen. This will suspend the process until
362: * some selected descriptor can be read, written, or has some other
363: * event pending. Note: if you want to implement SSH_MSG_IGNORE
364: * messages to fool traffic analysis, this might be the place to do
365: * it: just have a random timeout for the select, and send a random
366: * SSH_MSG_IGNORE packet when the timeout expires.
367: */
1.11 markus 368:
1.46 markus 369: if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) {
1.11 markus 370: char buf[100];
1.51 markus 371:
372: /*
373: * We have to clear the select masks, because we return.
374: * We have to return, because the mainloop checks for the flags
375: * set by the signal handlers.
376: */
1.87 markus 377: memset(*readsetp, 0, *nallocp);
378: memset(*writesetp, 0, *nallocp);
1.50 deraadt 379:
1.11 markus 380: if (errno == EINTR)
381: return;
382: /* Note: we might still have data in the buffers. */
383: snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
384: buffer_append(&stderr_buffer, buf, strlen(buf));
385: quit_pending = 1;
386: }
387: }
388:
1.77 itojun 389: static void
1.31 markus 390: client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
1.1 deraadt 391: {
1.11 markus 392: struct winsize oldws, newws;
393:
394: /* Flush stdout and stderr buffers. */
1.31 markus 395: if (buffer_len(bout) > 0)
1.112 deraadt 396: atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
1.31 markus 397: if (buffer_len(berr) > 0)
1.112 deraadt 398: atomicio(vwrite, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
1.11 markus 399:
400: leave_raw_mode();
401:
1.13 markus 402: /*
403: * Free (and clear) the buffer to reduce the amount of data that gets
404: * written to swap.
405: */
1.31 markus 406: buffer_free(bin);
407: buffer_free(bout);
408: buffer_free(berr);
1.11 markus 409:
410: /* Save old window size. */
411: ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
412:
413: /* Send the suspend signal to the program itself. */
414: kill(getpid(), SIGTSTP);
415:
416: /* Check if the window size has changed. */
417: if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 &&
418: (oldws.ws_row != newws.ws_row ||
1.90 deraadt 419: oldws.ws_col != newws.ws_col ||
420: oldws.ws_xpixel != newws.ws_xpixel ||
421: oldws.ws_ypixel != newws.ws_ypixel))
1.11 markus 422: received_window_change_signal = 1;
423:
424: /* OK, we have been continued by the user. Reinitialize buffers. */
1.31 markus 425: buffer_init(bin);
426: buffer_init(bout);
427: buffer_init(berr);
1.11 markus 428:
429: enter_raw_mode();
430: }
431:
1.77 itojun 432: static void
1.17 markus 433: client_process_net_input(fd_set * readset)
1.11 markus 434: {
1.17 markus 435: int len;
436: char buf[8192];
1.11 markus 437:
1.13 markus 438: /*
439: * Read input from the server, and add any such data to the buffer of
440: * the packet subsystem.
441: */
1.11 markus 442: if (FD_ISSET(connection_in, readset)) {
443: /* Read as much as possible. */
444: len = read(connection_in, buf, sizeof(buf));
445: if (len == 0) {
446: /* Received EOF. The remote host has closed the connection. */
447: snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
448: host);
1.1 deraadt 449: buffer_append(&stderr_buffer, buf, strlen(buf));
450: quit_pending = 1;
451: return;
1.11 markus 452: }
1.13 markus 453: /*
454: * There is a kernel bug on Solaris that causes select to
455: * sometimes wake up even though there is no data available.
456: */
1.53 millert 457: if (len < 0 && (errno == EAGAIN || errno == EINTR))
1.11 markus 458: len = 0;
459:
460: if (len < 0) {
461: /* An error has encountered. Perhaps there is a network problem. */
462: snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
463: host, strerror(errno));
464: buffer_append(&stderr_buffer, buf, strlen(buf));
465: quit_pending = 1;
466: return;
467: }
468: packet_process_incoming(buf, len);
469: }
1.17 markus 470: }
1.16 markus 471:
1.97 jakob 472: static void
1.99 markus 473: process_cmdline(void)
1.97 jakob 474: {
475: void (*handler)(int);
476: char *s, *cmd;
477: u_short fwd_port, fwd_host_port;
478: char buf[1024], sfwd_port[6], sfwd_host_port[6];
479: int local = 0;
480:
481: leave_raw_mode();
1.101 markus 482: handler = signal(SIGINT, SIG_IGN);
1.99 markus 483: cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
1.97 jakob 484: if (s == NULL)
485: goto out;
486: while (*s && isspace(*s))
487: s++;
488: if (*s == 0)
489: goto out;
490: if (strlen(s) < 2 || s[0] != '-' || !(s[1] == 'L' || s[1] == 'R')) {
1.109 itojun 491: logit("Invalid command.");
1.97 jakob 492: goto out;
493: }
494: if (s[1] == 'L')
495: local = 1;
496: if (!local && !compat20) {
1.109 itojun 497: logit("Not supported for SSH protocol version 1.");
1.97 jakob 498: goto out;
499: }
500: s += 2;
501: while (*s && isspace(*s))
502: s++;
503:
504: if (sscanf(s, "%5[0-9]:%255[^:]:%5[0-9]",
505: sfwd_port, buf, sfwd_host_port) != 3 &&
506: sscanf(s, "%5[0-9]/%255[^/]/%5[0-9]",
507: sfwd_port, buf, sfwd_host_port) != 3) {
1.109 itojun 508: logit("Bad forwarding specification.");
1.97 jakob 509: goto out;
510: }
511: if ((fwd_port = a2port(sfwd_port)) == 0 ||
512: (fwd_host_port = a2port(sfwd_host_port)) == 0) {
1.109 itojun 513: logit("Bad forwarding port(s).");
1.97 jakob 514: goto out;
515: }
516: if (local) {
1.99 markus 517: if (channel_setup_local_fwd_listener(fwd_port, buf,
518: fwd_host_port, options.gateway_ports) < 0) {
1.109 itojun 519: logit("Port forwarding failed.");
1.97 jakob 520: goto out;
521: }
522: } else
523: channel_request_remote_forwarding(fwd_port, buf,
524: fwd_host_port);
1.109 itojun 525: logit("Forwarding port.");
1.97 jakob 526: out:
527: signal(SIGINT, handler);
528: enter_raw_mode();
529: if (cmd)
530: xfree(cmd);
531: }
532:
1.31 markus 533: /* process the characters one by one */
1.77 itojun 534: static int
1.31 markus 535: process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
536: {
1.32 markus 537: char string[1024];
1.31 markus 538: pid_t pid;
539: int bytes = 0;
1.42 markus 540: u_int i;
541: u_char ch;
1.31 markus 542: char *s;
543:
544: for (i = 0; i < len; i++) {
545: /* Get one character at a time. */
546: ch = buf[i];
547:
548: if (escape_pending) {
549: /* We have previously seen an escape character. */
550: /* Clear the flag now. */
551: escape_pending = 0;
552:
553: /* Process the escaped character. */
554: switch (ch) {
555: case '.':
556: /* Terminate the connection. */
1.32 markus 557: snprintf(string, sizeof string, "%c.\r\n", escape_char);
558: buffer_append(berr, string, strlen(string));
1.31 markus 559:
560: quit_pending = 1;
561: return -1;
562:
563: case 'Z' - 64:
564: /* Suspend the program. */
565: /* Print a message to that effect to the user. */
1.32 markus 566: snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
567: buffer_append(berr, string, strlen(string));
1.31 markus 568:
569: /* Restore terminal modes and suspend. */
570: client_suspend_self(bin, bout, berr);
571:
572: /* We have been continued. */
573: continue;
574:
1.111 markus 575: case 'B':
576: if (compat20) {
577: snprintf(string, sizeof string,
578: "%cB\r\n", escape_char);
579: buffer_append(berr, string,
580: strlen(string));
581: channel_request_start(session_ident,
582: "break", 0);
583: packet_put_int(1000);
584: packet_send();
585: }
586: continue;
587:
1.54 markus 588: case 'R':
1.59 markus 589: if (compat20) {
590: if (datafellows & SSH_BUG_NOREKEY)
1.109 itojun 591: logit("Server does not support re-keying");
1.59 markus 592: else
593: need_rekeying = 1;
594: }
1.54 markus 595: continue;
596:
1.31 markus 597: case '&':
598: /*
599: * Detach the program (continue to serve connections,
600: * but put in background and no more new connections).
601: */
602: /* Restore tty modes. */
603: leave_raw_mode();
604:
605: /* Stop listening for new connections. */
1.86 markus 606: channel_stop_listening();
1.31 markus 607:
1.86 markus 608: snprintf(string, sizeof string,
609: "%c& [backgrounded]\n", escape_char);
610: buffer_append(berr, string, strlen(string));
1.31 markus 611:
612: /* Fork into background. */
613: pid = fork();
614: if (pid < 0) {
615: error("fork: %.100s", strerror(errno));
616: continue;
617: }
618: if (pid != 0) { /* This is the parent. */
619: /* The parent just exits. */
620: exit(0);
621: }
622: /* The child continues serving connections. */
1.86 markus 623: if (compat20) {
624: buffer_append(bin, "\004", 1);
625: /* fake EOF on stdin */
626: return -1;
627: } else if (!stdin_eof) {
628: /*
629: * Sending SSH_CMSG_EOF alone does not always appear
630: * to be enough. So we try to send an EOF character
631: * first.
632: */
633: packet_start(SSH_CMSG_STDIN_DATA);
634: packet_put_string("\004", 1);
635: packet_send();
636: /* Close stdin. */
637: stdin_eof = 1;
638: if (buffer_len(bin) == 0) {
639: packet_start(SSH_CMSG_EOF);
640: packet_send();
641: }
642: }
643: continue;
1.31 markus 644:
645: case '?':
1.32 markus 646: snprintf(string, sizeof string,
1.31 markus 647: "%c?\r\n\
648: Supported escape sequences:\r\n\
1.104 stevesk 649: %c. - terminate connection\r\n\
1.111 markus 650: %cB - send a BREAK to the remote system\r\n\
1.104 stevesk 651: %cC - open a command line\r\n\
652: %cR - Request rekey (SSH protocol 2 only)\r\n\
653: %c^Z - suspend ssh\r\n\
654: %c# - list forwarded connections\r\n\
655: %c& - background ssh (when waiting for connections to terminate)\r\n\
656: %c? - this message\r\n\
657: %c%c - send the escape character by typing it twice\r\n\
1.31 markus 658: (Note that escapes are only recognized immediately after newline.)\r\n",
1.104 stevesk 659: escape_char, escape_char, escape_char, escape_char,
660: escape_char, escape_char, escape_char, escape_char,
1.111 markus 661: escape_char, escape_char, escape_char);
1.32 markus 662: buffer_append(berr, string, strlen(string));
1.31 markus 663: continue;
664:
665: case '#':
1.32 markus 666: snprintf(string, sizeof string, "%c#\r\n", escape_char);
667: buffer_append(berr, string, strlen(string));
1.31 markus 668: s = channel_open_message();
669: buffer_append(berr, s, strlen(s));
670: xfree(s);
1.97 jakob 671: continue;
672:
673: case 'C':
1.99 markus 674: process_cmdline();
1.31 markus 675: continue;
676:
677: default:
678: if (ch != escape_char) {
679: buffer_put_char(bin, escape_char);
680: bytes++;
681: }
682: /* Escaped characters fall through here */
683: break;
684: }
685: } else {
686: /*
687: * The previous character was not an escape char. Check if this
688: * is an escape.
689: */
690: if (last_was_cr && ch == escape_char) {
691: /* It is. Set the flag and continue to next character. */
692: escape_pending = 1;
693: continue;
694: }
695: }
696:
697: /*
698: * Normal character. Record whether it was a newline,
699: * and append it to the buffer.
700: */
701: last_was_cr = (ch == '\r' || ch == '\n');
702: buffer_put_char(bin, ch);
703: bytes++;
704: }
705: return bytes;
706: }
707:
1.77 itojun 708: static void
1.17 markus 709: client_process_input(fd_set * readset)
710: {
1.21 deraadt 711: int len;
1.31 markus 712: char buf[8192];
1.16 markus 713:
1.11 markus 714: /* Read input from stdin. */
715: if (FD_ISSET(fileno(stdin), readset)) {
716: /* Read as much as possible. */
717: len = read(fileno(stdin), buf, sizeof(buf));
1.64 markus 718: if (len < 0 && (errno == EAGAIN || errno == EINTR))
719: return; /* we'll try again later */
1.11 markus 720: if (len <= 0) {
1.13 markus 721: /*
722: * Received EOF or error. They are treated
723: * similarly, except that an error message is printed
724: * if it was an error condition.
725: */
1.11 markus 726: if (len < 0) {
727: snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
728: buffer_append(&stderr_buffer, buf, strlen(buf));
729: }
730: /* Mark that we have seen EOF. */
731: stdin_eof = 1;
1.13 markus 732: /*
733: * Send an EOF message to the server unless there is
734: * data in the buffer. If there is data in the
735: * buffer, no message will be sent now. Code
736: * elsewhere will send the EOF when the buffer
737: * becomes empty if stdin_eof is set.
738: */
1.11 markus 739: if (buffer_len(&stdin_buffer) == 0) {
1.1 deraadt 740: packet_start(SSH_CMSG_EOF);
741: packet_send();
1.11 markus 742: }
1.72 stevesk 743: } else if (escape_char == SSH_ESCAPECHAR_NONE) {
1.13 markus 744: /*
745: * Normal successful read, and no escape character.
746: * Just append the data to buffer.
747: */
1.11 markus 748: buffer_append(&stdin_buffer, buf, len);
749: } else {
1.13 markus 750: /*
751: * Normal, successful read. But we have an escape character
752: * and have to process the characters one by one.
753: */
1.52 markus 754: if (process_escapes(&stdin_buffer, &stdout_buffer,
755: &stderr_buffer, buf, len) == -1)
1.31 markus 756: return;
1.11 markus 757: }
758: }
759: }
760:
1.77 itojun 761: static void
1.11 markus 762: client_process_output(fd_set * writeset)
763: {
764: int len;
765: char buf[100];
1.1 deraadt 766:
1.11 markus 767: /* Write buffered output to stdout. */
768: if (FD_ISSET(fileno(stdout), writeset)) {
769: /* Write as much data as possible. */
770: len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1.14 deraadt 771: buffer_len(&stdout_buffer));
1.11 markus 772: if (len <= 0) {
1.64 markus 773: if (errno == EINTR || errno == EAGAIN)
1.11 markus 774: len = 0;
775: else {
1.13 markus 776: /*
777: * An error or EOF was encountered. Put an
778: * error message to stderr buffer.
779: */
1.11 markus 780: snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
781: buffer_append(&stderr_buffer, buf, strlen(buf));
782: quit_pending = 1;
783: return;
784: }
785: }
786: /* Consume printed data from the buffer. */
787: buffer_consume(&stdout_buffer, len);
1.57 markus 788: stdout_bytes += len;
1.11 markus 789: }
790: /* Write buffered output to stderr. */
791: if (FD_ISSET(fileno(stderr), writeset)) {
792: /* Write as much data as possible. */
793: len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1.14 deraadt 794: buffer_len(&stderr_buffer));
1.11 markus 795: if (len <= 0) {
1.64 markus 796: if (errno == EINTR || errno == EAGAIN)
1.11 markus 797: len = 0;
798: else {
1.13 markus 799: /* EOF or error, but can't even print error message. */
1.11 markus 800: quit_pending = 1;
801: return;
802: }
803: }
804: /* Consume printed characters from the buffer. */
805: buffer_consume(&stderr_buffer, len);
1.57 markus 806: stderr_bytes += len;
1.11 markus 807: }
1.1 deraadt 808: }
809:
1.13 markus 810: /*
1.15 markus 811: * Get packets from the connection input buffer, and process them as long as
812: * there are packets available.
813: *
814: * Any unknown packets received during the actual
815: * session cause the session to terminate. This is
816: * intended to make debugging easier since no
817: * confirmations are sent. Any compatible protocol
818: * extensions must be negotiated during the
819: * preparatory phase.
820: */
821:
1.77 itojun 822: static void
1.49 itojun 823: client_process_buffered_input_packets(void)
1.15 markus 824: {
1.54 markus 825: dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL);
1.15 markus 826: }
827:
1.31 markus 828: /* scan buf[] for '~' before sending data to the peer */
1.30 markus 829:
1.77 itojun 830: static int
1.31 markus 831: simple_escape_filter(Channel *c, char *buf, int len)
1.30 markus 832: {
1.31 markus 833: /* XXX we assume c->extended is writeable */
834: return process_escapes(&c->input, &c->output, &c->extended, buf, len);
1.30 markus 835: }
836:
1.77 itojun 837: static void
1.60 markus 838: client_channel_closed(int id, void *arg)
839: {
840: if (id != session_ident)
841: error("client_channel_closed: id %d != session_ident %d",
842: id, session_ident);
1.83 markus 843: channel_cancel_cleanup(id);
1.60 markus 844: session_closed = 1;
1.113 ! markus 845: leave_raw_mode();
1.60 markus 846: }
847:
1.15 markus 848: /*
1.13 markus 849: * Implements the interactive session with the server. This is called after
850: * the user has been authenticated, and a command has been started on the
1.72 stevesk 851: * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character
852: * used as an escape character for terminating or suspending the session.
1.13 markus 853: */
1.1 deraadt 854:
1.20 markus 855: int
1.30 markus 856: client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1.1 deraadt 857: {
1.46 markus 858: fd_set *readset = NULL, *writeset = NULL;
1.11 markus 859: double start_time, total_time;
1.81 markus 860: int max_fd = 0, max_fd2 = 0, len, rekeying = 0, nalloc = 0;
1.11 markus 861: char buf[100];
862:
863: debug("Entering interactive session.");
864:
865: start_time = get_current_time();
866:
867: /* Initialize variables. */
868: escape_pending = 0;
869: last_was_cr = 1;
870: exit_status = -1;
871: stdin_eof = 0;
872: buffer_high = 64 * 1024;
873: connection_in = packet_get_connection_in();
874: connection_out = packet_get_connection_out();
1.46 markus 875: max_fd = MAX(connection_in, connection_out);
876:
877: if (!compat20) {
1.63 markus 878: /* enable nonblocking unless tty */
879: if (!isatty(fileno(stdin)))
880: set_nonblock(fileno(stdin));
881: if (!isatty(fileno(stdout)))
882: set_nonblock(fileno(stdout));
883: if (!isatty(fileno(stderr)))
884: set_nonblock(fileno(stderr));
1.46 markus 885: max_fd = MAX(max_fd, fileno(stdin));
886: max_fd = MAX(max_fd, fileno(stdout));
887: max_fd = MAX(max_fd, fileno(stderr));
888: }
1.11 markus 889: stdin_bytes = 0;
890: stdout_bytes = 0;
891: stderr_bytes = 0;
892: quit_pending = 0;
893: escape_char = escape_char_arg;
894:
895: /* Initialize buffers. */
896: buffer_init(&stdin_buffer);
897: buffer_init(&stdout_buffer);
898: buffer_init(&stderr_buffer);
899:
1.15 markus 900: client_init_dispatch();
901:
1.105 markus 902: /*
903: * Set signal handlers, (e.g. to restore non-blocking mode)
904: * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
905: */
906: if (signal(SIGINT, SIG_IGN) != SIG_IGN)
907: signal(SIGINT, signal_handler);
908: if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
909: signal(SIGQUIT, signal_handler);
910: if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
911: signal(SIGTERM, signal_handler);
1.11 markus 912: if (have_pty)
913: signal(SIGWINCH, window_change_handler);
914:
915: if (have_pty)
916: enter_raw_mode();
917:
1.48 markus 918: if (compat20) {
919: session_ident = ssh2_chan_id;
1.72 stevesk 920: if (escape_char != SSH_ESCAPECHAR_NONE)
1.48 markus 921: channel_register_filter(session_ident,
922: simple_escape_filter);
1.60 markus 923: if (session_ident != -1)
924: channel_register_cleanup(session_ident,
925: client_channel_closed);
1.48 markus 926: } else {
927: /* Check if we should immediately send eof on stdin. */
1.16 markus 928: client_check_initial_eof_on_stdin();
1.48 markus 929: }
1.30 markus 930:
1.11 markus 931: /* Main loop of the client for the interactive session mode. */
932: while (!quit_pending) {
933:
1.13 markus 934: /* Process buffered packets sent by the server. */
1.11 markus 935: client_process_buffered_input_packets();
936:
1.60 markus 937: if (compat20 && session_closed && !channel_still_open())
938: break;
939:
1.56 markus 940: rekeying = (xxx_kex != NULL && !xxx_kex->done);
1.16 markus 941:
1.56 markus 942: if (rekeying) {
943: debug("rekeying in progress");
944: } else {
945: /*
946: * Make packets of buffered stdin data, and buffer
947: * them for sending to the server.
948: */
949: if (!compat20)
950: client_make_packets_from_stdin_data();
1.11 markus 951:
1.56 markus 952: /*
953: * Make packets from buffered channel data, and
954: * enqueue them for sending to the server.
955: */
956: if (packet_not_very_much_data_to_write())
957: channel_output_poll();
1.11 markus 958:
1.56 markus 959: /*
960: * Check if the window size has changed, and buffer a
961: * message about it to the server if so.
962: */
963: client_check_window_change();
1.11 markus 964:
1.56 markus 965: if (quit_pending)
966: break;
967: }
1.13 markus 968: /*
969: * Wait until we have something to do (something becomes
970: * available on one of the descriptors).
971: */
1.81 markus 972: max_fd2 = max_fd;
1.56 markus 973: client_wait_until_can_do_something(&readset, &writeset,
1.81 markus 974: &max_fd2, &nalloc, rekeying);
1.11 markus 975:
976: if (quit_pending)
977: break;
978:
1.56 markus 979: /* Do channel operations unless rekeying in progress. */
980: if (!rekeying) {
981: channel_after_select(readset, writeset);
1.108 markus 982: if (need_rekeying || packet_need_rekeying()) {
983: debug("need rekeying");
1.56 markus 984: xxx_kex->done = 0;
985: kex_send_kexinit(xxx_kex);
986: need_rekeying = 0;
987: }
988: }
1.11 markus 989:
1.17 markus 990: /* Buffer input from the connection. */
1.46 markus 991: client_process_net_input(readset);
1.17 markus 992:
993: if (quit_pending)
994: break;
1.11 markus 995:
1.17 markus 996: if (!compat20) {
997: /* Buffer data from stdin */
1.46 markus 998: client_process_input(readset);
1.17 markus 999: /*
1000: * Process output to stdout and stderr. Output to
1001: * the connection is processed elsewhere (above).
1002: */
1.46 markus 1003: client_process_output(writeset);
1.17 markus 1004: }
1.11 markus 1005:
1.13 markus 1006: /* Send as much buffered packet data as possible to the sender. */
1.46 markus 1007: if (FD_ISSET(connection_out, writeset))
1.11 markus 1008: packet_write_poll();
1009: }
1.46 markus 1010: if (readset)
1011: xfree(readset);
1012: if (writeset)
1013: xfree(writeset);
1.11 markus 1014:
1015: /* Terminate the session. */
1016:
1017: /* Stop watching for window change. */
1018: if (have_pty)
1019: signal(SIGWINCH, SIG_DFL);
1020:
1.76 markus 1021: channel_free_all();
1.11 markus 1022:
1.75 markus 1023: if (have_pty)
1024: leave_raw_mode();
1025:
1026: /* restore blocking io */
1027: if (!isatty(fileno(stdin)))
1028: unset_nonblock(fileno(stdin));
1029: if (!isatty(fileno(stdout)))
1030: unset_nonblock(fileno(stdout));
1031: if (!isatty(fileno(stderr)))
1032: unset_nonblock(fileno(stderr));
1033:
1.113 ! markus 1034: if (received_signal)
1.89 itojun 1035: fatal("Killed by signal %d.", (int) received_signal);
1.75 markus 1036:
1.13 markus 1037: /*
1038: * In interactive mode (with pseudo tty) display a message indicating
1039: * that the connection has been closed.
1040: */
1.11 markus 1041: if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1042: snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
1043: buffer_append(&stderr_buffer, buf, strlen(buf));
1044: }
1.70 markus 1045:
1.11 markus 1046: /* Output any buffered data for stdout. */
1.70 markus 1047: while (buffer_len(&stdout_buffer) > 0) {
1048: len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1.14 deraadt 1049: buffer_len(&stdout_buffer));
1.70 markus 1050: if (len <= 0) {
1.11 markus 1051: error("Write failed flushing stdout buffer.");
1.70 markus 1052: break;
1053: }
1.11 markus 1054: buffer_consume(&stdout_buffer, len);
1.57 markus 1055: stdout_bytes += len;
1.11 markus 1056: }
1057:
1058: /* Output any buffered data for stderr. */
1.70 markus 1059: while (buffer_len(&stderr_buffer) > 0) {
1060: len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1.14 deraadt 1061: buffer_len(&stderr_buffer));
1.70 markus 1062: if (len <= 0) {
1.11 markus 1063: error("Write failed flushing stderr buffer.");
1.70 markus 1064: break;
1065: }
1.11 markus 1066: buffer_consume(&stderr_buffer, len);
1.57 markus 1067: stderr_bytes += len;
1.11 markus 1068: }
1069:
1070: /* Clear and free any buffers. */
1071: memset(buf, 0, sizeof(buf));
1072: buffer_free(&stdin_buffer);
1073: buffer_free(&stdout_buffer);
1074: buffer_free(&stderr_buffer);
1075:
1076: /* Report bytes transferred, and transfer rates. */
1077: total_time = get_current_time() - start_time;
1078: debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
1.90 deraadt 1079: stdin_bytes, stdout_bytes, stderr_bytes, total_time);
1.11 markus 1080: if (total_time > 0)
1081: debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
1.90 deraadt 1082: stdin_bytes / total_time, stdout_bytes / total_time,
1083: stderr_bytes / total_time);
1.11 markus 1084:
1085: /* Return the exit status of the program. */
1086: debug("Exit status %d", exit_status);
1087: return exit_status;
1.15 markus 1088: }
1089:
1090: /*********/
1091:
1.77 itojun 1092: static void
1.94 markus 1093: client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1.15 markus 1094: {
1.42 markus 1095: u_int data_len;
1.15 markus 1096: char *data = packet_get_string(&data_len);
1.93 markus 1097: packet_check_eom();
1.15 markus 1098: buffer_append(&stdout_buffer, data, data_len);
1099: memset(data, 0, data_len);
1100: xfree(data);
1101: }
1.77 itojun 1102: static void
1.94 markus 1103: client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1.15 markus 1104: {
1.42 markus 1105: u_int data_len;
1.15 markus 1106: char *data = packet_get_string(&data_len);
1.93 markus 1107: packet_check_eom();
1.15 markus 1108: buffer_append(&stderr_buffer, data, data_len);
1109: memset(data, 0, data_len);
1110: xfree(data);
1111: }
1.77 itojun 1112: static void
1.94 markus 1113: client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1.15 markus 1114: {
1115: exit_status = packet_get_int();
1.93 markus 1116: packet_check_eom();
1.15 markus 1117: /* Acknowledge the exit. */
1118: packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1119: packet_send();
1120: /*
1121: * Must wait for packet to be sent since we are
1122: * exiting the loop.
1123: */
1124: packet_write_wait();
1125: /* Flag that we want to exit. */
1126: quit_pending = 1;
1127: }
1128:
1.77 itojun 1129: static Channel *
1.40 markus 1130: client_request_forwarded_tcpip(const char *request_type, int rchan)
1131: {
1.103 deraadt 1132: Channel *c = NULL;
1.40 markus 1133: char *listen_address, *originator_address;
1134: int listen_port, originator_port;
1.67 markus 1135: int sock;
1.40 markus 1136:
1137: /* Get rest of the packet */
1138: listen_address = packet_get_string(NULL);
1139: listen_port = packet_get_int();
1140: originator_address = packet_get_string(NULL);
1141: originator_port = packet_get_int();
1.93 markus 1142: packet_check_eom();
1.40 markus 1143:
1144: debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1145: listen_address, listen_port, originator_address, originator_port);
1146:
1.80 stevesk 1147: sock = channel_connect_by_listen_address(listen_port);
1.67 markus 1148: if (sock < 0) {
1149: xfree(originator_address);
1150: xfree(listen_address);
1151: return NULL;
1152: }
1153: c = channel_new("forwarded-tcpip",
1154: SSH_CHANNEL_CONNECTING, sock, sock, -1,
1155: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1.110 markus 1156: originator_address, 1);
1.40 markus 1157: xfree(originator_address);
1158: xfree(listen_address);
1159: return c;
1160: }
1161:
1.103 deraadt 1162: static Channel *
1.40 markus 1163: client_request_x11(const char *request_type, int rchan)
1164: {
1165: Channel *c = NULL;
1166: char *originator;
1167: int originator_port;
1.67 markus 1168: int sock;
1.40 markus 1169:
1170: if (!options.forward_x11) {
1171: error("Warning: ssh server tried X11 forwarding.");
1172: error("Warning: this is probably a break in attempt by a malicious server.");
1173: return NULL;
1174: }
1175: originator = packet_get_string(NULL);
1176: if (datafellows & SSH_BUG_X11FWD) {
1177: debug2("buggy server: x11 request w/o originator_port");
1178: originator_port = 0;
1179: } else {
1180: originator_port = packet_get_int();
1181: }
1.93 markus 1182: packet_check_eom();
1.40 markus 1183: /* XXX check permission */
1.47 markus 1184: debug("client_request_x11: request from %s %d", originator,
1185: originator_port);
1.67 markus 1186: xfree(originator);
1.40 markus 1187: sock = x11_connect_display();
1.67 markus 1188: if (sock < 0)
1189: return NULL;
1190: c = channel_new("x11",
1191: SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1.110 markus 1192: CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1.82 markus 1193: c->force_drain = 1;
1.40 markus 1194: return c;
1195: }
1196:
1.103 deraadt 1197: static Channel *
1.40 markus 1198: client_request_agent(const char *request_type, int rchan)
1199: {
1200: Channel *c = NULL;
1.67 markus 1201: int sock;
1.40 markus 1202:
1203: if (!options.forward_agent) {
1204: error("Warning: ssh server tried agent forwarding.");
1205: error("Warning: this is probably a break in attempt by a malicious server.");
1206: return NULL;
1207: }
1208: sock = ssh_get_authentication_socket();
1.67 markus 1209: if (sock < 0)
1210: return NULL;
1211: c = channel_new("authentication agent connection",
1212: SSH_CHANNEL_OPEN, sock, sock, -1,
1213: CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1.110 markus 1214: "authentication agent connection", 1);
1.82 markus 1215: c->force_drain = 1;
1.40 markus 1216: return c;
1217: }
1218:
1.22 markus 1219: /* XXXX move to generic input handler */
1.77 itojun 1220: static void
1.94 markus 1221: client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1.22 markus 1222: {
1223: Channel *c = NULL;
1224: char *ctype;
1225: int rchan;
1.102 markus 1226: u_int rmaxpack, rwindow, len;
1.22 markus 1227:
1228: ctype = packet_get_string(&len);
1229: rchan = packet_get_int();
1230: rwindow = packet_get_int();
1231: rmaxpack = packet_get_int();
1232:
1.24 markus 1233: debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1.22 markus 1234: ctype, rchan, rwindow, rmaxpack);
1235:
1.40 markus 1236: if (strcmp(ctype, "forwarded-tcpip") == 0) {
1237: c = client_request_forwarded_tcpip(ctype, rchan);
1238: } else if (strcmp(ctype, "x11") == 0) {
1239: c = client_request_x11(ctype, rchan);
1240: } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1241: c = client_request_agent(ctype, rchan);
1.22 markus 1242: }
1243: /* XXX duplicate : */
1244: if (c != NULL) {
1245: debug("confirm %s", ctype);
1246: c->remote_id = rchan;
1247: c->remote_window = rwindow;
1248: c->remote_maxpacket = rmaxpack;
1.69 markus 1249: if (c->type != SSH_CHANNEL_CONNECTING) {
1250: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1251: packet_put_int(c->remote_id);
1252: packet_put_int(c->self);
1253: packet_put_int(c->local_window);
1254: packet_put_int(c->local_maxpacket);
1255: packet_send();
1256: }
1.22 markus 1257: } else {
1258: debug("failure %s", ctype);
1259: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1260: packet_put_int(rchan);
1261: packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1.66 markus 1262: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.69 markus 1263: packet_put_cstring("open failed");
1.66 markus 1264: packet_put_cstring("");
1265: }
1.22 markus 1266: packet_send();
1267: }
1268: xfree(ctype);
1269: }
1.77 itojun 1270: static void
1.94 markus 1271: client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1.48 markus 1272: {
1273: Channel *c = NULL;
1274: int id, reply, success = 0;
1275: char *rtype;
1276:
1277: id = packet_get_int();
1278: rtype = packet_get_string(NULL);
1279: reply = packet_get_char();
1280:
1281: debug("client_input_channel_req: channel %d rtype %s reply %d",
1282: id, rtype, reply);
1283:
1284: if (session_ident == -1) {
1285: error("client_input_channel_req: no channel %d", session_ident);
1286: } else if (id != session_ident) {
1287: error("client_input_channel_req: channel %d: wrong channel: %d",
1288: session_ident, id);
1289: }
1290: c = channel_lookup(id);
1291: if (c == NULL) {
1292: error("client_input_channel_req: channel %d: unknown channel", id);
1293: } else if (strcmp(rtype, "exit-status") == 0) {
1294: success = 1;
1295: exit_status = packet_get_int();
1.93 markus 1296: packet_check_eom();
1.48 markus 1297: }
1298: if (reply) {
1299: packet_start(success ?
1300: SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1301: packet_put_int(c->remote_id);
1302: packet_send();
1303: }
1304: xfree(rtype);
1305: }
1.95 markus 1306: static void
1307: client_input_global_request(int type, u_int32_t seq, void *ctxt)
1308: {
1309: char *rtype;
1310: int want_reply;
1311: int success = 0;
1312:
1313: rtype = packet_get_string(NULL);
1314: want_reply = packet_get_char();
1315: debug("client_input_global_request: rtype %s want_reply %d", rtype, want_reply);
1316: if (want_reply) {
1317: packet_start(success ?
1318: SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1319: packet_send();
1320: packet_write_wait();
1321: }
1322: xfree(rtype);
1323: }
1.22 markus 1324:
1.77 itojun 1325: static void
1.49 itojun 1326: client_init_dispatch_20(void)
1.16 markus 1327: {
1.55 markus 1328: dispatch_init(&dispatch_protocol_error);
1.100 markus 1329:
1.16 markus 1330: dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1331: dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1332: dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1333: dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1.22 markus 1334: dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1.16 markus 1335: dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1336: dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1.48 markus 1337: dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1.16 markus 1338: dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1.95 markus 1339: dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1.55 markus 1340:
1341: /* rekeying */
1342: dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1.100 markus 1343:
1344: /* global request reply messages */
1345: dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
1346: dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1.16 markus 1347: }
1.77 itojun 1348: static void
1.49 itojun 1349: client_init_dispatch_13(void)
1.15 markus 1350: {
1351: dispatch_init(NULL);
1352: dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1353: dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1354: dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1355: dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1356: dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1357: dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1358: dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
1359: dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
1360: dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1.39 markus 1361:
1362: dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1363: &auth_input_open_request : &deny_input_open);
1364: dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
1365: &x11_input_open : &deny_input_open);
1.15 markus 1366: }
1.77 itojun 1367: static void
1.49 itojun 1368: client_init_dispatch_15(void)
1.15 markus 1369: {
1370: client_init_dispatch_13();
1371: dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1372: dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
1373: }
1.79 stevesk 1374: static void
1.49 itojun 1375: client_init_dispatch(void)
1.15 markus 1376: {
1.16 markus 1377: if (compat20)
1378: client_init_dispatch_20();
1379: else if (compat13)
1.15 markus 1380: client_init_dispatch_13();
1381: else
1382: client_init_dispatch_15();
1.113 ! markus 1383: }
! 1384:
! 1385: /* client specific fatal cleanup */
! 1386: void
! 1387: fatal(const char *fmt,...)
! 1388: {
! 1389: va_list args;
! 1390:
! 1391: va_start(args, fmt);
! 1392: do_log(SYSLOG_LEVEL_FATAL, fmt, args);
! 1393: va_end(args);
! 1394: leave_raw_mode();
! 1395: leave_non_blocking();
! 1396: _exit(255);
1.1 deraadt 1397: }
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