Annotation of src/usr.bin/ssh/clientloop.c, Revision 1.235
1.235 ! djm 1: /* $OpenBSD: clientloop.c,v 1.234 2011/05/08 12:52:01 djm Exp $ */
1.1 deraadt 2: /*
1.12 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
1.33 deraadt 6: * The main loop for the interactive session (client side).
1.20 markus 7: *
1.33 deraadt 8: * As far as I am concerned, the code I have written for this software
9: * can be used freely for any purpose. Any derived versions of this
10: * software must be clearly marked as such, and if the derived work is
11: * incompatible with the protocol description in the RFC file, it must be
12: * called by a name other than "ssh" or "Secure Shell".
13: *
14: *
15: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
16: *
17: * Redistribution and use in source and binary forms, with or without
18: * modification, are permitted provided that the following conditions
19: * are met:
20: * 1. Redistributions of source code must retain the above copyright
21: * notice, this list of conditions and the following disclaimer.
22: * 2. Redistributions in binary form must reproduce the above copyright
23: * notice, this list of conditions and the following disclaimer in the
24: * documentation and/or other materials provided with the distribution.
25: *
26: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.20 markus 36: *
37: *
1.33 deraadt 38: * SSH2 support added by Markus Friedl.
1.78 markus 39: * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
1.20 markus 40: *
1.33 deraadt 41: * Redistribution and use in source and binary forms, with or without
42: * modification, are permitted provided that the following conditions
43: * are met:
44: * 1. Redistributions of source code must retain the above copyright
45: * notice, this list of conditions and the following disclaimer.
46: * 2. Redistributions in binary form must reproduce the above copyright
47: * notice, this list of conditions and the following disclaimer in the
48: * documentation and/or other materials provided with the distribution.
49: *
50: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
51: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
52: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
53: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
54: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
55: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
56: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
57: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
58: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
59: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.12 deraadt 60: */
1.1 deraadt 61:
1.152 stevesk 62:
1.175 deraadt 63: #include <sys/types.h>
1.152 stevesk 64: #include <sys/ioctl.h>
1.154 stevesk 65: #include <sys/stat.h>
1.166 stevesk 66: #include <sys/socket.h>
1.171 stevesk 67: #include <sys/time.h>
1.172 stevesk 68: #include <sys/param.h>
1.189 djm 69: #include <sys/queue.h>
1.150 stevesk 70:
1.155 stevesk 71: #include <ctype.h>
1.168 stevesk 72: #include <errno.h>
1.151 stevesk 73: #include <paths.h>
1.153 stevesk 74: #include <signal.h>
1.174 stevesk 75: #include <stdio.h>
1.173 stevesk 76: #include <stdlib.h>
1.170 stevesk 77: #include <string.h>
1.150 stevesk 78: #include <termios.h>
1.175 deraadt 79: #include <pwd.h>
1.169 stevesk 80: #include <unistd.h>
1.1 deraadt 81:
1.175 deraadt 82: #include "xmalloc.h"
1.45 markus 83: #include "ssh.h"
84: #include "ssh1.h"
85: #include "ssh2.h"
1.1 deraadt 86: #include "packet.h"
87: #include "buffer.h"
1.15 markus 88: #include "compat.h"
1.74 markus 89: #include "channels.h"
1.15 markus 90: #include "dispatch.h"
1.40 markus 91: #include "key.h"
1.175 deraadt 92: #include "cipher.h"
1.54 markus 93: #include "kex.h"
1.45 markus 94: #include "log.h"
95: #include "readconf.h"
96: #include "clientloop.h"
1.147 djm 97: #include "sshconnect.h"
1.40 markus 98: #include "authfd.h"
1.45 markus 99: #include "atomicio.h"
1.118 deraadt 100: #include "sshpty.h"
1.63 markus 101: #include "misc.h"
1.123 djm 102: #include "match.h"
103: #include "msg.h"
1.212 andreas 104: #include "roaming.h"
1.39 markus 105:
106: /* import options */
107: extern Options options;
108:
1.1 deraadt 109: /* Flag indicating that stdin should be redirected from /dev/null. */
110: extern int stdin_null_flag;
111:
1.116 dtucker 112: /* Flag indicating that no shell has been requested */
113: extern int no_shell_flag;
114:
1.123 djm 115: /* Control socket */
1.217 djm 116: extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */
1.123 djm 117:
1.13 markus 118: /*
119: * Name of the host we are connecting to. This is the name given on the
120: * command line, or the HostName specified for the user-supplied name in a
121: * configuration file.
122: */
1.1 deraadt 123: extern char *host;
124:
1.13 markus 125: /*
126: * Flag to indicate that we have received a window change signal which has
127: * not yet been processed. This will cause a message indicating the new
128: * window size to be sent to the server a little later. This is volatile
129: * because this is updated in a signal handler.
130: */
1.88 markus 131: static volatile sig_atomic_t received_window_change_signal = 0;
132: static volatile sig_atomic_t received_signal = 0;
1.1 deraadt 133:
1.145 djm 134: /* Flag indicating whether the user's terminal is in non-blocking mode. */
1.1 deraadt 135: static int in_non_blocking_mode = 0;
136:
1.222 djm 137: /* Time when backgrounded control master using ControlPersist should exit */
138: static time_t control_persist_exit_time = 0;
139:
1.1 deraadt 140: /* Common data for the client loop code. */
1.217 djm 141: volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
1.195 djm 142: static int escape_char1; /* Escape character. (proto1 only) */
143: static int escape_pending1; /* Last character was an escape (proto1 only) */
1.11 markus 144: static int last_was_cr; /* Last character was a newline. */
1.197 djm 145: static int exit_status; /* Used to store the command exit status. */
146: static int stdin_eof; /* EOF has been encountered on stderr. */
1.11 markus 147: static Buffer stdin_buffer; /* Buffer for stdin data. */
148: static Buffer stdout_buffer; /* Buffer for stdout data. */
149: static Buffer stderr_buffer; /* Buffer for stderr data. */
1.221 djm 150: static u_int buffer_high; /* Soft max buffer size. */
1.11 markus 151: static int connection_in; /* Connection to server (input). */
152: static int connection_out; /* Connection to server (output). */
1.56 markus 153: static int need_rekeying; /* Set to non-zero if rekeying is requested. */
1.221 djm 154: static int session_closed; /* In SSH2: login session closed. */
155: static int x11_refuse_time; /* If >0, refuse x11 opens after this time. */
1.1 deraadt 156:
1.77 itojun 157: static void client_init_dispatch(void);
1.16 markus 158: int session_ident = -1;
159:
1.214 andreas 160: int session_resumed = 0;
161:
1.195 djm 162: /* Track escape per proto2 channel */
163: struct escape_filter_ctx {
164: int escape_pending;
165: int escape_char;
166: };
167:
168: /* Context for channel confirmation replies */
1.234 djm 169: enum confirm_action { CONFIRM_WARN = 0, CONFIRM_CLOSE, CONFIRM_TTY };
1.190 djm 170: struct channel_reply_ctx {
171: const char *request_type;
1.234 djm 172: int id;
173: enum confirm_action action;
1.190 djm 174: };
175:
1.196 djm 176: /* Global request success/failure callbacks */
177: struct global_confirm {
178: TAILQ_ENTRY(global_confirm) entry;
179: global_confirm_cb *cb;
180: void *ctx;
181: int ref_count;
182: };
183: TAILQ_HEAD(global_confirms, global_confirm);
184: static struct global_confirms global_confirms =
185: TAILQ_HEAD_INITIALIZER(global_confirms);
186:
1.54 markus 187: /*XXX*/
188: extern Kex *xxx_kex;
189:
1.123 djm 190: void ssh_process_session2_setup(int, int, int, Buffer *);
191:
1.1 deraadt 192: /* Restores stdin to blocking mode. */
193:
1.77 itojun 194: static void
1.49 itojun 195: leave_non_blocking(void)
1.1 deraadt 196: {
1.11 markus 197: if (in_non_blocking_mode) {
1.125 djm 198: unset_nonblock(fileno(stdin));
1.11 markus 199: in_non_blocking_mode = 0;
200: }
1.1 deraadt 201: }
202:
1.11 markus 203: /* Puts stdin terminal in non-blocking mode. */
204:
1.77 itojun 205: static void
1.49 itojun 206: enter_non_blocking(void)
1.1 deraadt 207: {
1.11 markus 208: in_non_blocking_mode = 1;
1.124 djm 209: set_nonblock(fileno(stdin));
1.1 deraadt 210: }
211:
1.13 markus 212: /*
213: * Signal handler for the window change signal (SIGWINCH). This just sets a
214: * flag indicating that the window has changed.
215: */
1.157 deraadt 216: /*ARGSUSED */
1.77 itojun 217: static void
1.11 markus 218: window_change_handler(int sig)
1.1 deraadt 219: {
1.11 markus 220: received_window_change_signal = 1;
221: signal(SIGWINCH, window_change_handler);
1.1 deraadt 222: }
223:
1.13 markus 224: /*
225: * Signal handler for signals that cause the program to terminate. These
226: * signals must be trapped to restore terminal modes.
227: */
1.157 deraadt 228: /*ARGSUSED */
1.77 itojun 229: static void
1.11 markus 230: signal_handler(int sig)
1.1 deraadt 231: {
1.75 markus 232: received_signal = sig;
233: quit_pending = 1;
1.1 deraadt 234: }
235:
1.13 markus 236: /*
237: * Returns current time in seconds from Jan 1, 1970 with the maximum
238: * available resolution.
239: */
1.1 deraadt 240:
1.77 itojun 241: static double
1.49 itojun 242: get_current_time(void)
1.1 deraadt 243: {
1.11 markus 244: struct timeval tv;
245: gettimeofday(&tv, NULL);
246: return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
1.138 djm 247: }
248:
1.222 djm 249: /*
250: * Sets control_persist_exit_time to the absolute time when the
251: * backgrounded control master should exit due to expiry of the
252: * ControlPersist timeout. Sets it to 0 if we are not a backgrounded
253: * control master process, or if there is no ControlPersist timeout.
254: */
255: static void
256: set_control_persist_exit_time(void)
257: {
258: if (muxserver_sock == -1 || !options.control_persist
1.232 djm 259: || options.control_persist_timeout == 0) {
1.222 djm 260: /* not using a ControlPersist timeout */
261: control_persist_exit_time = 0;
1.232 djm 262: } else if (channel_still_open()) {
1.222 djm 263: /* some client connections are still open */
264: if (control_persist_exit_time > 0)
265: debug2("%s: cancel scheduled exit", __func__);
266: control_persist_exit_time = 0;
267: } else if (control_persist_exit_time <= 0) {
268: /* a client connection has recently closed */
269: control_persist_exit_time = time(NULL) +
270: (time_t)options.control_persist_timeout;
271: debug2("%s: schedule exit in %d seconds", __func__,
272: options.control_persist_timeout);
273: }
274: /* else we are already counting down to the timeout */
275: }
276:
1.138 djm 277: #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
278: void
279: client_x11_get_proto(const char *display, const char *xauth_path,
1.221 djm 280: u_int trusted, u_int timeout, char **_proto, char **_data)
1.138 djm 281: {
282: char cmd[1024];
283: char line[512];
284: char xdisplay[512];
285: static char proto[512], data[512];
286: FILE *f;
287: int got_data = 0, generated = 0, do_unlink = 0, i;
288: char *xauthdir, *xauthfile;
289: struct stat st;
1.221 djm 290: u_int now;
1.138 djm 291:
292: xauthdir = xauthfile = NULL;
293: *_proto = proto;
294: *_data = data;
295: proto[0] = data[0] = '\0';
296:
297: if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
298: debug("No xauth program.");
299: } else {
300: if (display == NULL) {
301: debug("x11_get_proto: DISPLAY not set");
302: return;
303: }
304: /*
305: * Handle FamilyLocal case where $DISPLAY does
306: * not match an authorization entry. For this we
307: * just try "xauth list unix:displaynum.screennum".
308: * XXX: "localhost" match to determine FamilyLocal
309: * is not perfect.
310: */
311: if (strncmp(display, "localhost:", 10) == 0) {
312: snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
313: display + 10);
314: display = xdisplay;
315: }
316: if (trusted == 0) {
317: xauthdir = xmalloc(MAXPATHLEN);
318: xauthfile = xmalloc(MAXPATHLEN);
1.225 djm 319: mktemp_proto(xauthdir, MAXPATHLEN);
1.138 djm 320: if (mkdtemp(xauthdir) != NULL) {
321: do_unlink = 1;
322: snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
323: xauthdir);
324: snprintf(cmd, sizeof(cmd),
325: "%s -f %s generate %s " SSH_X11_PROTO
1.221 djm 326: " untrusted timeout %u 2>" _PATH_DEVNULL,
327: xauth_path, xauthfile, display, timeout);
1.138 djm 328: debug2("x11_get_proto: %s", cmd);
329: if (system(cmd) == 0)
330: generated = 1;
1.221 djm 331: if (x11_refuse_time == 0) {
332: now = time(NULL) + 1;
333: if (UINT_MAX - timeout < now)
334: x11_refuse_time = UINT_MAX;
335: else
336: x11_refuse_time = now + timeout;
337: }
1.138 djm 338: }
339: }
1.181 markus 340:
341: /*
342: * When in untrusted mode, we read the cookie only if it was
343: * successfully generated as an untrusted one in the step
344: * above.
345: */
346: if (trusted || generated) {
347: snprintf(cmd, sizeof(cmd),
348: "%s %s%s list %s 2>" _PATH_DEVNULL,
349: xauth_path,
350: generated ? "-f " : "" ,
351: generated ? xauthfile : "",
352: display);
353: debug2("x11_get_proto: %s", cmd);
354: f = popen(cmd, "r");
355: if (f && fgets(line, sizeof(line), f) &&
356: sscanf(line, "%*s %511s %511s", proto, data) == 2)
357: got_data = 1;
358: if (f)
359: pclose(f);
360: } else
361: error("Warning: untrusted X11 forwarding setup failed: "
362: "xauth key data not generated");
1.138 djm 363: }
364:
365: if (do_unlink) {
366: unlink(xauthfile);
367: rmdir(xauthdir);
368: }
369: if (xauthdir)
370: xfree(xauthdir);
371: if (xauthfile)
372: xfree(xauthfile);
373:
374: /*
375: * If we didn't get authentication data, just make up some
376: * data. The forwarding code will check the validity of the
377: * response anyway, and substitute this data. The X11
378: * server, however, will ignore this fake data and use
379: * whatever authentication mechanisms it was using otherwise
380: * for the local connection.
381: */
382: if (!got_data) {
383: u_int32_t rnd = 0;
384:
385: logit("Warning: No xauth data; "
386: "using fake authentication data for X11 forwarding.");
387: strlcpy(proto, SSH_X11_PROTO, sizeof proto);
388: for (i = 0; i < 16; i++) {
389: if (i % 4 == 0)
390: rnd = arc4random();
391: snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
392: rnd & 0xff);
393: rnd >>= 8;
394: }
395: }
1.1 deraadt 396: }
397:
1.13 markus 398: /*
399: * This is called when the interactive is entered. This checks if there is
400: * an EOF coming on stdin. We must check this explicitly, as select() does
401: * not appear to wake up when redirecting from /dev/null.
402: */
1.1 deraadt 403:
1.77 itojun 404: static void
1.49 itojun 405: client_check_initial_eof_on_stdin(void)
1.1 deraadt 406: {
1.11 markus 407: int len;
408: char buf[1];
1.1 deraadt 409:
1.13 markus 410: /*
411: * If standard input is to be "redirected from /dev/null", we simply
412: * mark that we have seen an EOF and send an EOF message to the
413: * server. Otherwise, we try to read a single character; it appears
414: * that for some files, such /dev/null, select() never wakes up for
415: * read for this descriptor, which means that we never get EOF. This
416: * way we will get the EOF if stdin comes from /dev/null or similar.
417: */
1.11 markus 418: if (stdin_null_flag) {
419: /* Fake EOF on stdin. */
420: debug("Sending eof.");
421: stdin_eof = 1;
422: packet_start(SSH_CMSG_EOF);
423: packet_send();
424: } else {
425: enter_non_blocking();
426:
427: /* Check for immediate EOF on stdin. */
428: len = read(fileno(stdin), buf, 1);
429: if (len == 0) {
1.197 djm 430: /*
431: * EOF. Record that we have seen it and send
432: * EOF to server.
433: */
1.11 markus 434: debug("Sending eof.");
435: stdin_eof = 1;
436: packet_start(SSH_CMSG_EOF);
437: packet_send();
438: } else if (len > 0) {
1.13 markus 439: /*
440: * Got data. We must store the data in the buffer,
441: * and also process it as an escape character if
442: * appropriate.
443: */
1.195 djm 444: if ((u_char) buf[0] == escape_char1)
445: escape_pending1 = 1;
1.52 markus 446: else
1.11 markus 447: buffer_append(&stdin_buffer, buf, 1);
448: }
449: leave_non_blocking();
450: }
1.1 deraadt 451: }
452:
453:
1.13 markus 454: /*
455: * Make packets from buffered stdin data, and buffer them for sending to the
456: * connection.
457: */
1.1 deraadt 458:
1.77 itojun 459: static void
1.49 itojun 460: client_make_packets_from_stdin_data(void)
1.1 deraadt 461: {
1.42 markus 462: u_int len;
1.1 deraadt 463:
1.11 markus 464: /* Send buffered stdin data to the server. */
465: while (buffer_len(&stdin_buffer) > 0 &&
1.90 deraadt 466: packet_not_very_much_data_to_write()) {
1.11 markus 467: len = buffer_len(&stdin_buffer);
468: /* Keep the packets at reasonable size. */
469: if (len > packet_get_maxsize())
470: len = packet_get_maxsize();
471: packet_start(SSH_CMSG_STDIN_DATA);
472: packet_put_string(buffer_ptr(&stdin_buffer), len);
473: packet_send();
474: buffer_consume(&stdin_buffer, len);
475: /* If we have a pending EOF, send it now. */
476: if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
477: packet_start(SSH_CMSG_EOF);
478: packet_send();
479: }
1.1 deraadt 480: }
481: }
482:
1.13 markus 483: /*
484: * Checks if the client window has changed, and sends a packet about it to
485: * the server if so. The actual change is detected elsewhere (by a software
486: * interrupt on Unix); this just checks the flag and sends a message if
487: * appropriate.
488: */
1.1 deraadt 489:
1.77 itojun 490: static void
1.49 itojun 491: client_check_window_change(void)
1.1 deraadt 492: {
1.16 markus 493: struct winsize ws;
494:
495: if (! received_window_change_signal)
496: return;
497: /** XXX race */
498: received_window_change_signal = 0;
499:
1.37 markus 500: debug2("client_check_window_change: changed");
1.16 markus 501:
502: if (compat20) {
1.123 djm 503: channel_send_window_changes();
1.16 markus 504: } else {
1.123 djm 505: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
506: return;
1.16 markus 507: packet_start(SSH_CMSG_WINDOW_SIZE);
1.158 deraadt 508: packet_put_int((u_int)ws.ws_row);
509: packet_put_int((u_int)ws.ws_col);
510: packet_put_int((u_int)ws.ws_xpixel);
511: packet_put_int((u_int)ws.ws_ypixel);
1.16 markus 512: packet_send();
1.1 deraadt 513: }
514: }
515:
1.117 markus 516: static void
517: client_global_request_reply(int type, u_int32_t seq, void *ctxt)
518: {
1.196 djm 519: struct global_confirm *gc;
520:
521: if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
522: return;
523: if (gc->cb != NULL)
524: gc->cb(type, seq, gc->ctx);
525: if (--gc->ref_count <= 0) {
526: TAILQ_REMOVE(&global_confirms, gc, entry);
527: bzero(gc, sizeof(*gc));
528: xfree(gc);
529: }
530:
1.210 andreas 531: packet_set_alive_timeouts(0);
1.117 markus 532: }
533:
534: static void
535: server_alive_check(void)
536: {
1.210 andreas 537: if (packet_inc_alive_timeouts() > options.server_alive_count_max) {
1.228 djm 538: logit("Timeout, server %s not responding.", host);
1.176 markus 539: cleanup_exit(255);
540: }
1.117 markus 541: packet_start(SSH2_MSG_GLOBAL_REQUEST);
542: packet_put_cstring("keepalive@openssh.com");
543: packet_put_char(1); /* boolean: want reply */
544: packet_send();
1.196 djm 545: /* Insert an empty placeholder to maintain ordering */
546: client_register_global_confirm(NULL, NULL);
1.117 markus 547: }
548:
1.13 markus 549: /*
550: * Waits until the client can do something (some data becomes available on
551: * one of the file descriptors).
552: */
1.77 itojun 553: static void
1.46 markus 554: client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
1.130 avsm 555: int *maxfdp, u_int *nallocp, int rekeying)
1.11 markus 556: {
1.117 markus 557: struct timeval tv, *tvp;
1.222 djm 558: int timeout_secs;
1.117 markus 559: int ret;
560:
1.46 markus 561: /* Add any selections by the channel mechanism. */
1.81 markus 562: channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
1.11 markus 563:
1.16 markus 564: if (!compat20) {
1.17 markus 565: /* Read from the connection, unless our buffers are full. */
1.16 markus 566: if (buffer_len(&stdout_buffer) < buffer_high &&
567: buffer_len(&stderr_buffer) < buffer_high &&
568: channel_not_very_much_buffered_data())
1.46 markus 569: FD_SET(connection_in, *readsetp);
1.17 markus 570: /*
571: * Read from stdin, unless we have seen EOF or have very much
572: * buffered data to send to the server.
573: */
574: if (!stdin_eof && packet_not_very_much_data_to_write())
1.46 markus 575: FD_SET(fileno(stdin), *readsetp);
1.17 markus 576:
577: /* Select stdout/stderr if have data in buffer. */
578: if (buffer_len(&stdout_buffer) > 0)
1.46 markus 579: FD_SET(fileno(stdout), *writesetp);
1.17 markus 580: if (buffer_len(&stderr_buffer) > 0)
1.46 markus 581: FD_SET(fileno(stderr), *writesetp);
1.16 markus 582: } else {
1.71 markus 583: /* channel_prepare_select could have closed the last channel */
1.84 markus 584: if (session_closed && !channel_still_open() &&
585: !packet_have_data_to_write()) {
586: /* clear mask since we did not call select() */
1.87 markus 587: memset(*readsetp, 0, *nallocp);
588: memset(*writesetp, 0, *nallocp);
1.84 markus 589: return;
1.71 markus 590: } else {
591: FD_SET(connection_in, *readsetp);
592: }
1.16 markus 593: }
1.11 markus 594:
595: /* Select server connection if have data to write to the server. */
596: if (packet_have_data_to_write())
1.46 markus 597: FD_SET(connection_out, *writesetp);
1.11 markus 598:
1.13 markus 599: /*
600: * Wait for something to happen. This will suspend the process until
601: * some selected descriptor can be read, written, or has some other
1.222 djm 602: * event pending, or a timeout expires.
1.13 markus 603: */
1.11 markus 604:
1.222 djm 605: timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */
606: if (options.server_alive_interval > 0 && compat20)
607: timeout_secs = options.server_alive_interval;
608: set_control_persist_exit_time();
609: if (control_persist_exit_time > 0) {
610: timeout_secs = MIN(timeout_secs,
611: control_persist_exit_time - time(NULL));
612: if (timeout_secs < 0)
613: timeout_secs = 0;
614: }
615: if (timeout_secs == INT_MAX)
1.117 markus 616: tvp = NULL;
1.129 deraadt 617: else {
1.222 djm 618: tv.tv_sec = timeout_secs;
1.117 markus 619: tv.tv_usec = 0;
620: tvp = &tv;
621: }
1.222 djm 622:
1.117 markus 623: ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
624: if (ret < 0) {
1.11 markus 625: char buf[100];
1.51 markus 626:
627: /*
628: * We have to clear the select masks, because we return.
629: * We have to return, because the mainloop checks for the flags
630: * set by the signal handlers.
631: */
1.87 markus 632: memset(*readsetp, 0, *nallocp);
633: memset(*writesetp, 0, *nallocp);
1.50 deraadt 634:
1.11 markus 635: if (errno == EINTR)
636: return;
637: /* Note: we might still have data in the buffers. */
638: snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
639: buffer_append(&stderr_buffer, buf, strlen(buf));
640: quit_pending = 1;
1.117 markus 641: } else if (ret == 0)
642: server_alive_check();
1.11 markus 643: }
644:
1.77 itojun 645: static void
1.31 markus 646: client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
1.1 deraadt 647: {
1.11 markus 648: /* Flush stdout and stderr buffers. */
1.31 markus 649: if (buffer_len(bout) > 0)
1.197 djm 650: atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
651: buffer_len(bout));
1.31 markus 652: if (buffer_len(berr) > 0)
1.197 djm 653: atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
654: buffer_len(berr));
1.11 markus 655:
1.233 djm 656: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.11 markus 657:
1.13 markus 658: /*
659: * Free (and clear) the buffer to reduce the amount of data that gets
660: * written to swap.
661: */
1.31 markus 662: buffer_free(bin);
663: buffer_free(bout);
664: buffer_free(berr);
1.11 markus 665:
666: /* Send the suspend signal to the program itself. */
667: kill(getpid(), SIGTSTP);
668:
1.132 djm 669: /* Reset window sizes in case they have changed */
670: received_window_change_signal = 1;
1.11 markus 671:
672: /* OK, we have been continued by the user. Reinitialize buffers. */
1.31 markus 673: buffer_init(bin);
674: buffer_init(bout);
675: buffer_init(berr);
1.11 markus 676:
1.233 djm 677: enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.11 markus 678: }
679:
1.77 itojun 680: static void
1.161 deraadt 681: client_process_net_input(fd_set *readset)
1.11 markus 682: {
1.212 andreas 683: int len, cont = 0;
1.17 markus 684: char buf[8192];
1.11 markus 685:
1.13 markus 686: /*
687: * Read input from the server, and add any such data to the buffer of
688: * the packet subsystem.
689: */
1.11 markus 690: if (FD_ISSET(connection_in, readset)) {
691: /* Read as much as possible. */
1.212 andreas 692: len = roaming_read(connection_in, buf, sizeof(buf), &cont);
693: if (len == 0 && cont == 0) {
1.197 djm 694: /*
695: * Received EOF. The remote host has closed the
696: * connection.
697: */
698: snprintf(buf, sizeof buf,
699: "Connection to %.300s closed by remote host.\r\n",
700: host);
1.1 deraadt 701: buffer_append(&stderr_buffer, buf, strlen(buf));
702: quit_pending = 1;
703: return;
1.11 markus 704: }
1.13 markus 705: /*
706: * There is a kernel bug on Solaris that causes select to
707: * sometimes wake up even though there is no data available.
708: */
1.53 millert 709: if (len < 0 && (errno == EAGAIN || errno == EINTR))
1.11 markus 710: len = 0;
711:
712: if (len < 0) {
1.197 djm 713: /*
714: * An error has encountered. Perhaps there is a
715: * network problem.
716: */
717: snprintf(buf, sizeof buf,
718: "Read from remote host %.300s: %.100s\r\n",
719: host, strerror(errno));
1.11 markus 720: buffer_append(&stderr_buffer, buf, strlen(buf));
721: quit_pending = 1;
722: return;
723: }
724: packet_process_incoming(buf, len);
725: }
1.17 markus 726: }
1.16 markus 727:
1.97 jakob 728: static void
1.190 djm 729: client_status_confirm(int type, Channel *c, void *ctx)
1.123 djm 730: {
1.190 djm 731: struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
732: char errmsg[256];
733: int tochan;
734:
1.234 djm 735: /*
736: * If a TTY was explicitly requested, then a failure to allocate
737: * one is fatal.
738: */
739: if (cr->action == CONFIRM_TTY &&
740: (options.request_tty == REQUEST_TTY_FORCE ||
741: options.request_tty == REQUEST_TTY_YES))
742: cr->action = CONFIRM_CLOSE;
743:
1.190 djm 744: /* XXX supress on mux _client_ quietmode */
745: tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
1.217 djm 746: c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
1.190 djm 747:
748: if (type == SSH2_MSG_CHANNEL_SUCCESS) {
749: debug2("%s request accepted on channel %d",
750: cr->request_type, c->self);
751: } else if (type == SSH2_MSG_CHANNEL_FAILURE) {
752: if (tochan) {
753: snprintf(errmsg, sizeof(errmsg),
754: "%s request failed\r\n", cr->request_type);
755: } else {
756: snprintf(errmsg, sizeof(errmsg),
757: "%s request failed on channel %d",
758: cr->request_type, c->self);
759: }
760: /* If error occurred on primary session channel, then exit */
1.234 djm 761: if (cr->action == CONFIRM_CLOSE && c->self == session_ident)
1.190 djm 762: fatal("%s", errmsg);
1.234 djm 763: /*
764: * If error occurred on mux client, append to
765: * their stderr.
766: */
767: if (tochan) {
768: buffer_append(&c->extended, errmsg,
769: strlen(errmsg));
770: } else
1.190 djm 771: error("%s", errmsg);
1.234 djm 772: if (cr->action == CONFIRM_TTY) {
773: /*
774: * If a TTY allocation error occurred, then arrange
775: * for the correct TTY to leave raw mode.
776: */
777: if (c->self == session_ident)
778: leave_raw_mode(0);
779: else
780: mux_tty_alloc_failed(c);
781: } else if (cr->action == CONFIRM_CLOSE) {
1.190 djm 782: chan_read_failed(c);
783: chan_write_failed(c);
784: }
785: }
786: xfree(cr);
787: }
788:
789: static void
790: client_abandon_status_confirm(Channel *c, void *ctx)
791: {
792: xfree(ctx);
793: }
1.129 deraadt 794:
1.190 djm 795: static void
1.234 djm 796: client_expect_confirm(int id, const char *request,
797: enum confirm_action action)
1.190 djm 798: {
799: struct channel_reply_ctx *cr = xmalloc(sizeof(*cr));
1.123 djm 800:
1.190 djm 801: cr->request_type = request;
1.234 djm 802: cr->action = action;
1.123 djm 803:
1.190 djm 804: channel_register_status_confirm(id, client_status_confirm,
805: client_abandon_status_confirm, cr);
1.196 djm 806: }
807:
808: void
809: client_register_global_confirm(global_confirm_cb *cb, void *ctx)
810: {
1.201 djm 811: struct global_confirm *gc, *last_gc;
1.196 djm 812:
813: /* Coalesce identical callbacks */
1.201 djm 814: last_gc = TAILQ_LAST(&global_confirms, global_confirms);
815: if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
816: if (++last_gc->ref_count >= INT_MAX)
817: fatal("%s: last_gc->ref_count = %d",
818: __func__, last_gc->ref_count);
1.196 djm 819: return;
820: }
821:
822: gc = xmalloc(sizeof(*gc));
823: gc->cb = cb;
824: gc->ctx = ctx;
825: gc->ref_count = 1;
826: TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
1.123 djm 827: }
828:
829: static void
1.99 markus 830: process_cmdline(void)
1.97 jakob 831: {
832: void (*handler)(int);
1.135 djm 833: char *s, *cmd, *cancel_host;
1.121 djm 834: int delete = 0;
1.204 stevesk 835: int local = 0, remote = 0, dynamic = 0;
1.208 djm 836: int cancel_port;
1.135 djm 837: Forward fwd;
1.97 jakob 838:
1.183 djm 839: bzero(&fwd, sizeof(fwd));
840: fwd.listen_host = fwd.connect_host = NULL;
841:
1.233 djm 842: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.101 markus 843: handler = signal(SIGINT, SIG_IGN);
1.99 markus 844: cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
1.97 jakob 845: if (s == NULL)
846: goto out;
1.179 tedu 847: while (isspace(*s))
1.97 jakob 848: s++;
1.121 djm 849: if (*s == '-')
850: s++; /* Skip cmdline '-', if any */
1.120 dtucker 851: if (*s == '\0')
1.97 jakob 852: goto out;
1.121 djm 853:
1.122 djm 854: if (*s == 'h' || *s == 'H' || *s == '?') {
1.121 djm 855: logit("Commands:");
1.164 djm 856: logit(" -L[bind_address:]port:host:hostport "
857: "Request local forward");
858: logit(" -R[bind_address:]port:host:hostport "
859: "Request remote forward");
1.204 stevesk 860: logit(" -D[bind_address:]port "
861: "Request dynamic forward");
1.165 stevesk 862: logit(" -KR[bind_address:]port "
1.164 djm 863: "Cancel remote forward");
1.146 reyk 864: if (!options.permit_local_command)
865: goto out;
1.164 djm 866: logit(" !args "
867: "Execute local command");
1.146 reyk 868: goto out;
869: }
870:
871: if (*s == '!' && options.permit_local_command) {
872: s++;
873: ssh_local_cmd(s);
1.121 djm 874: goto out;
875: }
876:
877: if (*s == 'K') {
878: delete = 1;
879: s++;
880: }
1.204 stevesk 881: if (*s == 'L')
882: local = 1;
883: else if (*s == 'R')
884: remote = 1;
885: else if (*s == 'D')
886: dynamic = 1;
887: else {
1.109 itojun 888: logit("Invalid command.");
1.97 jakob 889: goto out;
890: }
1.204 stevesk 891:
892: if ((local || dynamic) && delete) {
1.121 djm 893: logit("Not supported.");
894: goto out;
895: }
1.204 stevesk 896: if (remote && delete && !compat20) {
1.109 itojun 897: logit("Not supported for SSH protocol version 1.");
1.97 jakob 898: goto out;
899: }
1.121 djm 900:
1.179 tedu 901: while (isspace(*++s))
902: ;
1.97 jakob 903:
1.217 djm 904: /* XXX update list of forwards in options */
1.121 djm 905: if (delete) {
1.135 djm 906: cancel_port = 0;
907: cancel_host = hpdelim(&s); /* may be NULL */
908: if (s != NULL) {
909: cancel_port = a2port(s);
910: cancel_host = cleanhostname(cancel_host);
911: } else {
912: cancel_port = a2port(cancel_host);
913: cancel_host = NULL;
1.121 djm 914: }
1.208 djm 915: if (cancel_port <= 0) {
1.135 djm 916: logit("Bad forwarding close port");
1.121 djm 917: goto out;
918: }
1.135 djm 919: channel_request_rforward_cancel(cancel_host, cancel_port);
1.121 djm 920: } else {
1.209 djm 921: if (!parse_forward(&fwd, s, dynamic, remote)) {
1.121 djm 922: logit("Bad forwarding specification.");
923: goto out;
924: }
1.204 stevesk 925: if (local || dynamic) {
1.135 djm 926: if (channel_setup_local_fwd_listener(fwd.listen_host,
927: fwd.listen_port, fwd.connect_host,
928: fwd.connect_port, options.gateway_ports) < 0) {
1.121 djm 929: logit("Port forwarding failed.");
930: goto out;
931: }
1.135 djm 932: } else {
1.167 markus 933: if (channel_request_remote_forwarding(fwd.listen_host,
1.135 djm 934: fwd.listen_port, fwd.connect_host,
1.167 markus 935: fwd.connect_port) < 0) {
936: logit("Port forwarding failed.");
937: goto out;
938: }
1.135 djm 939: }
940:
1.121 djm 941: logit("Forwarding port.");
942: }
943:
1.97 jakob 944: out:
945: signal(SIGINT, handler);
1.233 djm 946: enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.97 jakob 947: if (cmd)
948: xfree(cmd);
1.183 djm 949: if (fwd.listen_host != NULL)
950: xfree(fwd.listen_host);
951: if (fwd.connect_host != NULL)
952: xfree(fwd.connect_host);
1.97 jakob 953: }
954:
1.195 djm 955: /*
956: * Process the characters one by one, call with c==NULL for proto1 case.
957: */
1.77 itojun 958: static int
1.195 djm 959: process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
960: char *buf, int len)
1.31 markus 961: {
1.32 markus 962: char string[1024];
1.31 markus 963: pid_t pid;
964: int bytes = 0;
1.42 markus 965: u_int i;
966: u_char ch;
1.31 markus 967: char *s;
1.195 djm 968: int *escape_pendingp, escape_char;
969: struct escape_filter_ctx *efc;
1.31 markus 970:
1.195 djm 971: if (c == NULL) {
972: escape_pendingp = &escape_pending1;
973: escape_char = escape_char1;
974: } else {
975: if (c->filter_ctx == NULL)
976: return 0;
977: efc = (struct escape_filter_ctx *)c->filter_ctx;
978: escape_pendingp = &efc->escape_pending;
979: escape_char = efc->escape_char;
980: }
981:
1.139 djm 982: if (len <= 0)
983: return (0);
984:
985: for (i = 0; i < (u_int)len; i++) {
1.31 markus 986: /* Get one character at a time. */
987: ch = buf[i];
988:
1.195 djm 989: if (*escape_pendingp) {
1.31 markus 990: /* We have previously seen an escape character. */
991: /* Clear the flag now. */
1.195 djm 992: *escape_pendingp = 0;
1.31 markus 993:
994: /* Process the escaped character. */
995: switch (ch) {
996: case '.':
997: /* Terminate the connection. */
1.195 djm 998: snprintf(string, sizeof string, "%c.\r\n",
999: escape_char);
1.32 markus 1000: buffer_append(berr, string, strlen(string));
1.31 markus 1001:
1.217 djm 1002: if (c && c->ctl_chan != -1) {
1.195 djm 1003: chan_read_failed(c);
1004: chan_write_failed(c);
1005: return 0;
1006: } else
1007: quit_pending = 1;
1.31 markus 1008: return -1;
1009:
1010: case 'Z' - 64:
1.195 djm 1011: /* XXX support this for mux clients */
1.217 djm 1012: if (c && c->ctl_chan != -1) {
1.195 djm 1013: noescape:
1014: snprintf(string, sizeof string,
1015: "%c%c escape not available to "
1016: "multiplexed sessions\r\n",
1017: escape_char, ch);
1018: buffer_append(berr, string,
1019: strlen(string));
1020: continue;
1021: }
1.197 djm 1022: /* Suspend the program. Inform the user */
1.195 djm 1023: snprintf(string, sizeof string,
1024: "%c^Z [suspend ssh]\r\n", escape_char);
1.32 markus 1025: buffer_append(berr, string, strlen(string));
1.31 markus 1026:
1027: /* Restore terminal modes and suspend. */
1028: client_suspend_self(bin, bout, berr);
1029:
1030: /* We have been continued. */
1031: continue;
1032:
1.111 markus 1033: case 'B':
1034: if (compat20) {
1035: snprintf(string, sizeof string,
1036: "%cB\r\n", escape_char);
1037: buffer_append(berr, string,
1038: strlen(string));
1039: channel_request_start(session_ident,
1040: "break", 0);
1041: packet_put_int(1000);
1042: packet_send();
1043: }
1044: continue;
1045:
1.54 markus 1046: case 'R':
1.59 markus 1047: if (compat20) {
1048: if (datafellows & SSH_BUG_NOREKEY)
1.197 djm 1049: logit("Server does not "
1050: "support re-keying");
1.59 markus 1051: else
1052: need_rekeying = 1;
1053: }
1.54 markus 1054: continue;
1055:
1.31 markus 1056: case '&':
1.217 djm 1057: if (c && c->ctl_chan != -1)
1.195 djm 1058: goto noescape;
1.31 markus 1059: /*
1.197 djm 1060: * Detach the program (continue to serve
1061: * connections, but put in background and no
1062: * more new connections).
1.31 markus 1063: */
1064: /* Restore tty modes. */
1.233 djm 1065: leave_raw_mode(
1066: options.request_tty == REQUEST_TTY_FORCE);
1.31 markus 1067:
1068: /* Stop listening for new connections. */
1.86 markus 1069: channel_stop_listening();
1.31 markus 1070:
1.86 markus 1071: snprintf(string, sizeof string,
1072: "%c& [backgrounded]\n", escape_char);
1073: buffer_append(berr, string, strlen(string));
1.31 markus 1074:
1075: /* Fork into background. */
1076: pid = fork();
1077: if (pid < 0) {
1078: error("fork: %.100s", strerror(errno));
1079: continue;
1080: }
1081: if (pid != 0) { /* This is the parent. */
1082: /* The parent just exits. */
1083: exit(0);
1084: }
1085: /* The child continues serving connections. */
1.86 markus 1086: if (compat20) {
1087: buffer_append(bin, "\004", 1);
1088: /* fake EOF on stdin */
1089: return -1;
1090: } else if (!stdin_eof) {
1091: /*
1.197 djm 1092: * Sending SSH_CMSG_EOF alone does not
1093: * always appear to be enough. So we
1094: * try to send an EOF character first.
1.86 markus 1095: */
1096: packet_start(SSH_CMSG_STDIN_DATA);
1097: packet_put_string("\004", 1);
1098: packet_send();
1099: /* Close stdin. */
1100: stdin_eof = 1;
1101: if (buffer_len(bin) == 0) {
1102: packet_start(SSH_CMSG_EOF);
1103: packet_send();
1104: }
1105: }
1106: continue;
1.31 markus 1107:
1108: case '?':
1.217 djm 1109: if (c && c->ctl_chan != -1) {
1.195 djm 1110: snprintf(string, sizeof string,
1111: "%c?\r\n\
1112: Supported escape sequences:\r\n\
1113: %c. - terminate session\r\n\
1114: %cB - send a BREAK to the remote system\r\n\
1115: %cR - Request rekey (SSH protocol 2 only)\r\n\
1116: %c# - list forwarded connections\r\n\
1117: %c? - this message\r\n\
1118: %c%c - send the escape character by typing it twice\r\n\
1119: (Note that escapes are only recognized immediately after newline.)\r\n",
1120: escape_char, escape_char,
1121: escape_char, escape_char,
1122: escape_char, escape_char,
1.206 djm 1123: escape_char, escape_char);
1.195 djm 1124: } else {
1125: snprintf(string, sizeof string,
1.31 markus 1126: "%c?\r\n\
1127: Supported escape sequences:\r\n\
1.195 djm 1128: %c. - terminate connection (and any multiplexed sessions)\r\n\
1129: %cB - send a BREAK to the remote system\r\n\
1130: %cC - open a command line\r\n\
1131: %cR - Request rekey (SSH protocol 2 only)\r\n\
1132: %c^Z - suspend ssh\r\n\
1133: %c# - list forwarded connections\r\n\
1134: %c& - background ssh (when waiting for connections to terminate)\r\n\
1135: %c? - this message\r\n\
1136: %c%c - send the escape character by typing it twice\r\n\
1.31 markus 1137: (Note that escapes are only recognized immediately after newline.)\r\n",
1.195 djm 1138: escape_char, escape_char,
1139: escape_char, escape_char,
1140: escape_char, escape_char,
1141: escape_char, escape_char,
1142: escape_char, escape_char,
1143: escape_char);
1144: }
1.32 markus 1145: buffer_append(berr, string, strlen(string));
1.31 markus 1146: continue;
1147:
1148: case '#':
1.195 djm 1149: snprintf(string, sizeof string, "%c#\r\n",
1150: escape_char);
1.32 markus 1151: buffer_append(berr, string, strlen(string));
1.31 markus 1152: s = channel_open_message();
1153: buffer_append(berr, s, strlen(s));
1154: xfree(s);
1.97 jakob 1155: continue;
1156:
1157: case 'C':
1.217 djm 1158: if (c && c->ctl_chan != -1)
1.206 djm 1159: goto noescape;
1.99 markus 1160: process_cmdline();
1.31 markus 1161: continue;
1162:
1163: default:
1164: if (ch != escape_char) {
1165: buffer_put_char(bin, escape_char);
1166: bytes++;
1167: }
1168: /* Escaped characters fall through here */
1169: break;
1170: }
1171: } else {
1172: /*
1.197 djm 1173: * The previous character was not an escape char.
1174: * Check if this is an escape.
1.31 markus 1175: */
1176: if (last_was_cr && ch == escape_char) {
1.197 djm 1177: /*
1178: * It is. Set the flag and continue to
1179: * next character.
1180: */
1.195 djm 1181: *escape_pendingp = 1;
1.31 markus 1182: continue;
1183: }
1184: }
1185:
1186: /*
1187: * Normal character. Record whether it was a newline,
1188: * and append it to the buffer.
1189: */
1190: last_was_cr = (ch == '\r' || ch == '\n');
1191: buffer_put_char(bin, ch);
1192: bytes++;
1193: }
1194: return bytes;
1195: }
1196:
1.77 itojun 1197: static void
1.161 deraadt 1198: client_process_input(fd_set *readset)
1.17 markus 1199: {
1.21 deraadt 1200: int len;
1.31 markus 1201: char buf[8192];
1.16 markus 1202:
1.11 markus 1203: /* Read input from stdin. */
1204: if (FD_ISSET(fileno(stdin), readset)) {
1205: /* Read as much as possible. */
1206: len = read(fileno(stdin), buf, sizeof(buf));
1.64 markus 1207: if (len < 0 && (errno == EAGAIN || errno == EINTR))
1208: return; /* we'll try again later */
1.11 markus 1209: if (len <= 0) {
1.13 markus 1210: /*
1211: * Received EOF or error. They are treated
1212: * similarly, except that an error message is printed
1213: * if it was an error condition.
1214: */
1.11 markus 1215: if (len < 0) {
1.197 djm 1216: snprintf(buf, sizeof buf, "read: %.100s\r\n",
1217: strerror(errno));
1.11 markus 1218: buffer_append(&stderr_buffer, buf, strlen(buf));
1219: }
1220: /* Mark that we have seen EOF. */
1221: stdin_eof = 1;
1.13 markus 1222: /*
1223: * Send an EOF message to the server unless there is
1224: * data in the buffer. If there is data in the
1225: * buffer, no message will be sent now. Code
1226: * elsewhere will send the EOF when the buffer
1227: * becomes empty if stdin_eof is set.
1228: */
1.11 markus 1229: if (buffer_len(&stdin_buffer) == 0) {
1.1 deraadt 1230: packet_start(SSH_CMSG_EOF);
1231: packet_send();
1.11 markus 1232: }
1.195 djm 1233: } else if (escape_char1 == SSH_ESCAPECHAR_NONE) {
1.13 markus 1234: /*
1235: * Normal successful read, and no escape character.
1236: * Just append the data to buffer.
1237: */
1.11 markus 1238: buffer_append(&stdin_buffer, buf, len);
1239: } else {
1.13 markus 1240: /*
1.197 djm 1241: * Normal, successful read. But we have an escape
1242: * character and have to process the characters one
1243: * by one.
1.13 markus 1244: */
1.195 djm 1245: if (process_escapes(NULL, &stdin_buffer,
1246: &stdout_buffer, &stderr_buffer, buf, len) == -1)
1.31 markus 1247: return;
1.11 markus 1248: }
1249: }
1250: }
1251:
1.77 itojun 1252: static void
1.161 deraadt 1253: client_process_output(fd_set *writeset)
1.11 markus 1254: {
1255: int len;
1256: char buf[100];
1.1 deraadt 1257:
1.11 markus 1258: /* Write buffered output to stdout. */
1259: if (FD_ISSET(fileno(stdout), writeset)) {
1260: /* Write as much data as possible. */
1261: len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1.14 deraadt 1262: buffer_len(&stdout_buffer));
1.11 markus 1263: if (len <= 0) {
1.64 markus 1264: if (errno == EINTR || errno == EAGAIN)
1.11 markus 1265: len = 0;
1266: else {
1.13 markus 1267: /*
1268: * An error or EOF was encountered. Put an
1269: * error message to stderr buffer.
1270: */
1.197 djm 1271: snprintf(buf, sizeof buf,
1272: "write stdout: %.50s\r\n", strerror(errno));
1.11 markus 1273: buffer_append(&stderr_buffer, buf, strlen(buf));
1274: quit_pending = 1;
1275: return;
1276: }
1277: }
1278: /* Consume printed data from the buffer. */
1279: buffer_consume(&stdout_buffer, len);
1280: }
1281: /* Write buffered output to stderr. */
1282: if (FD_ISSET(fileno(stderr), writeset)) {
1283: /* Write as much data as possible. */
1284: len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1.14 deraadt 1285: buffer_len(&stderr_buffer));
1.11 markus 1286: if (len <= 0) {
1.64 markus 1287: if (errno == EINTR || errno == EAGAIN)
1.11 markus 1288: len = 0;
1289: else {
1.197 djm 1290: /*
1291: * EOF or error, but can't even print
1292: * error message.
1293: */
1.11 markus 1294: quit_pending = 1;
1295: return;
1296: }
1297: }
1298: /* Consume printed characters from the buffer. */
1299: buffer_consume(&stderr_buffer, len);
1300: }
1.1 deraadt 1301: }
1302:
1.13 markus 1303: /*
1.15 markus 1304: * Get packets from the connection input buffer, and process them as long as
1305: * there are packets available.
1306: *
1307: * Any unknown packets received during the actual
1308: * session cause the session to terminate. This is
1309: * intended to make debugging easier since no
1310: * confirmations are sent. Any compatible protocol
1311: * extensions must be negotiated during the
1312: * preparatory phase.
1313: */
1314:
1.77 itojun 1315: static void
1.49 itojun 1316: client_process_buffered_input_packets(void)
1.15 markus 1317: {
1.197 djm 1318: dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
1319: compat20 ? xxx_kex : NULL);
1.15 markus 1320: }
1321:
1.31 markus 1322: /* scan buf[] for '~' before sending data to the peer */
1.30 markus 1323:
1.195 djm 1324: /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1325: void *
1326: client_new_escape_filter_ctx(int escape_char)
1327: {
1328: struct escape_filter_ctx *ret;
1329:
1330: ret = xmalloc(sizeof(*ret));
1331: ret->escape_pending = 0;
1332: ret->escape_char = escape_char;
1333: return (void *)ret;
1334: }
1335:
1.198 djm 1336: /* Free the escape filter context on channel free */
1337: void
1338: client_filter_cleanup(int cid, void *ctx)
1339: {
1340: xfree(ctx);
1341: }
1342:
1.195 djm 1343: int
1344: client_simple_escape_filter(Channel *c, char *buf, int len)
1.30 markus 1345: {
1.190 djm 1346: if (c->extended_usage != CHAN_EXTENDED_WRITE)
1347: return 0;
1348:
1.195 djm 1349: return process_escapes(c, &c->input, &c->output, &c->extended,
1350: buf, len);
1.30 markus 1351: }
1352:
1.77 itojun 1353: static void
1.60 markus 1354: client_channel_closed(int id, void *arg)
1355: {
1.83 markus 1356: channel_cancel_cleanup(id);
1.60 markus 1357: session_closed = 1;
1.233 djm 1358: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.60 markus 1359: }
1360:
1.15 markus 1361: /*
1.13 markus 1362: * Implements the interactive session with the server. This is called after
1363: * the user has been authenticated, and a command has been started on the
1.72 stevesk 1364: * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1365: * used as an escape character for terminating or suspending the session.
1.13 markus 1366: */
1.1 deraadt 1367:
1.20 markus 1368: int
1.30 markus 1369: client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1.1 deraadt 1370: {
1.46 markus 1371: fd_set *readset = NULL, *writeset = NULL;
1.11 markus 1372: double start_time, total_time;
1.130 avsm 1373: int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1.200 markus 1374: u_int64_t ibytes, obytes;
1.130 avsm 1375: u_int nalloc = 0;
1.11 markus 1376: char buf[100];
1377:
1378: debug("Entering interactive session.");
1379:
1380: start_time = get_current_time();
1381:
1382: /* Initialize variables. */
1.195 djm 1383: escape_pending1 = 0;
1.11 markus 1384: last_was_cr = 1;
1385: exit_status = -1;
1386: stdin_eof = 0;
1387: buffer_high = 64 * 1024;
1388: connection_in = packet_get_connection_in();
1389: connection_out = packet_get_connection_out();
1.46 markus 1390: max_fd = MAX(connection_in, connection_out);
1391:
1392: if (!compat20) {
1.63 markus 1393: /* enable nonblocking unless tty */
1394: if (!isatty(fileno(stdin)))
1395: set_nonblock(fileno(stdin));
1396: if (!isatty(fileno(stdout)))
1397: set_nonblock(fileno(stdout));
1398: if (!isatty(fileno(stderr)))
1399: set_nonblock(fileno(stderr));
1.46 markus 1400: max_fd = MAX(max_fd, fileno(stdin));
1401: max_fd = MAX(max_fd, fileno(stdout));
1402: max_fd = MAX(max_fd, fileno(stderr));
1403: }
1.11 markus 1404: quit_pending = 0;
1.195 djm 1405: escape_char1 = escape_char_arg;
1.11 markus 1406:
1407: /* Initialize buffers. */
1408: buffer_init(&stdin_buffer);
1409: buffer_init(&stdout_buffer);
1410: buffer_init(&stderr_buffer);
1411:
1.15 markus 1412: client_init_dispatch();
1413:
1.105 markus 1414: /*
1415: * Set signal handlers, (e.g. to restore non-blocking mode)
1416: * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1417: */
1.131 djm 1418: if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1419: signal(SIGHUP, signal_handler);
1.105 markus 1420: if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1421: signal(SIGINT, signal_handler);
1422: if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1423: signal(SIGQUIT, signal_handler);
1424: if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1425: signal(SIGTERM, signal_handler);
1.132 djm 1426: signal(SIGWINCH, window_change_handler);
1.11 markus 1427:
1428: if (have_pty)
1.233 djm 1429: enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.11 markus 1430:
1.48 markus 1431: if (compat20) {
1432: session_ident = ssh2_chan_id;
1.232 djm 1433: if (session_ident != -1) {
1434: if (escape_char_arg != SSH_ESCAPECHAR_NONE) {
1435: channel_register_filter(session_ident,
1436: client_simple_escape_filter, NULL,
1437: client_filter_cleanup,
1438: client_new_escape_filter_ctx(
1439: escape_char_arg));
1440: }
1.60 markus 1441: channel_register_cleanup(session_ident,
1.143 djm 1442: client_channel_closed, 0);
1.232 djm 1443: }
1.48 markus 1444: } else {
1445: /* Check if we should immediately send eof on stdin. */
1.16 markus 1446: client_check_initial_eof_on_stdin();
1.48 markus 1447: }
1.30 markus 1448:
1.11 markus 1449: /* Main loop of the client for the interactive session mode. */
1450: while (!quit_pending) {
1451:
1.13 markus 1452: /* Process buffered packets sent by the server. */
1.11 markus 1453: client_process_buffered_input_packets();
1454:
1.60 markus 1455: if (compat20 && session_closed && !channel_still_open())
1456: break;
1457:
1.56 markus 1458: rekeying = (xxx_kex != NULL && !xxx_kex->done);
1.16 markus 1459:
1.56 markus 1460: if (rekeying) {
1461: debug("rekeying in progress");
1462: } else {
1463: /*
1464: * Make packets of buffered stdin data, and buffer
1465: * them for sending to the server.
1466: */
1467: if (!compat20)
1468: client_make_packets_from_stdin_data();
1.11 markus 1469:
1.56 markus 1470: /*
1471: * Make packets from buffered channel data, and
1472: * enqueue them for sending to the server.
1473: */
1474: if (packet_not_very_much_data_to_write())
1475: channel_output_poll();
1.11 markus 1476:
1.56 markus 1477: /*
1478: * Check if the window size has changed, and buffer a
1479: * message about it to the server if so.
1480: */
1481: client_check_window_change();
1.11 markus 1482:
1.56 markus 1483: if (quit_pending)
1484: break;
1485: }
1.13 markus 1486: /*
1487: * Wait until we have something to do (something becomes
1488: * available on one of the descriptors).
1489: */
1.81 markus 1490: max_fd2 = max_fd;
1.56 markus 1491: client_wait_until_can_do_something(&readset, &writeset,
1.81 markus 1492: &max_fd2, &nalloc, rekeying);
1.11 markus 1493:
1494: if (quit_pending)
1495: break;
1496:
1.56 markus 1497: /* Do channel operations unless rekeying in progress. */
1498: if (!rekeying) {
1499: channel_after_select(readset, writeset);
1.108 markus 1500: if (need_rekeying || packet_need_rekeying()) {
1501: debug("need rekeying");
1.56 markus 1502: xxx_kex->done = 0;
1503: kex_send_kexinit(xxx_kex);
1504: need_rekeying = 0;
1505: }
1506: }
1.11 markus 1507:
1.17 markus 1508: /* Buffer input from the connection. */
1.46 markus 1509: client_process_net_input(readset);
1.17 markus 1510:
1511: if (quit_pending)
1512: break;
1.11 markus 1513:
1.17 markus 1514: if (!compat20) {
1515: /* Buffer data from stdin */
1.46 markus 1516: client_process_input(readset);
1.17 markus 1517: /*
1518: * Process output to stdout and stderr. Output to
1519: * the connection is processed elsewhere (above).
1520: */
1.46 markus 1521: client_process_output(writeset);
1.214 andreas 1522: }
1523:
1524: if (session_resumed) {
1525: connection_in = packet_get_connection_in();
1526: connection_out = packet_get_connection_out();
1527: max_fd = MAX(max_fd, connection_out);
1528: max_fd = MAX(max_fd, connection_in);
1529: session_resumed = 0;
1.17 markus 1530: }
1.11 markus 1531:
1.197 djm 1532: /*
1533: * Send as much buffered packet data as possible to the
1534: * sender.
1535: */
1.46 markus 1536: if (FD_ISSET(connection_out, writeset))
1.11 markus 1537: packet_write_poll();
1.222 djm 1538:
1539: /*
1540: * If we are a backgrounded control master, and the
1541: * timeout has expired without any active client
1542: * connections, then quit.
1543: */
1544: if (control_persist_exit_time > 0) {
1545: if (time(NULL) >= control_persist_exit_time) {
1546: debug("ControlPersist timeout expired");
1547: break;
1548: }
1549: }
1.11 markus 1550: }
1.46 markus 1551: if (readset)
1552: xfree(readset);
1553: if (writeset)
1554: xfree(writeset);
1.11 markus 1555:
1556: /* Terminate the session. */
1557:
1558: /* Stop watching for window change. */
1.132 djm 1559: signal(SIGWINCH, SIG_DFL);
1.211 andreas 1560:
1.213 stevesk 1561: if (compat20) {
1562: packet_start(SSH2_MSG_DISCONNECT);
1563: packet_put_int(SSH2_DISCONNECT_BY_APPLICATION);
1564: packet_put_cstring("disconnected by user");
1.219 djm 1565: packet_put_cstring(""); /* language tag */
1.213 stevesk 1566: packet_send();
1567: packet_write_wait();
1568: }
1.11 markus 1569:
1.76 markus 1570: channel_free_all();
1.11 markus 1571:
1.75 markus 1572: if (have_pty)
1.233 djm 1573: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.75 markus 1574:
1575: /* restore blocking io */
1576: if (!isatty(fileno(stdin)))
1577: unset_nonblock(fileno(stdin));
1578: if (!isatty(fileno(stdout)))
1579: unset_nonblock(fileno(stdout));
1580: if (!isatty(fileno(stderr)))
1581: unset_nonblock(fileno(stderr));
1.116 dtucker 1582:
1583: /*
1584: * If there was no shell or command requested, there will be no remote
1585: * exit status to be returned. In that case, clear error code if the
1586: * connection was deliberately terminated at this end.
1587: */
1588: if (no_shell_flag && received_signal == SIGTERM) {
1589: received_signal = 0;
1590: exit_status = 0;
1591: }
1.75 markus 1592:
1.113 markus 1593: if (received_signal)
1.89 itojun 1594: fatal("Killed by signal %d.", (int) received_signal);
1.75 markus 1595:
1.13 markus 1596: /*
1597: * In interactive mode (with pseudo tty) display a message indicating
1598: * that the connection has been closed.
1599: */
1.11 markus 1600: if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1.197 djm 1601: snprintf(buf, sizeof buf,
1602: "Connection to %.64s closed.\r\n", host);
1.11 markus 1603: buffer_append(&stderr_buffer, buf, strlen(buf));
1604: }
1.70 markus 1605:
1.11 markus 1606: /* Output any buffered data for stdout. */
1.231 djm 1607: if (buffer_len(&stdout_buffer) > 0) {
1.230 djm 1608: len = atomicio(vwrite, fileno(stdout),
1609: buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer));
1.231 djm 1610: if (len < 0 || (u_int)len != buffer_len(&stdout_buffer))
1.11 markus 1611: error("Write failed flushing stdout buffer.");
1.231 djm 1612: else
1613: buffer_consume(&stdout_buffer, len);
1.11 markus 1614: }
1615:
1616: /* Output any buffered data for stderr. */
1.231 djm 1617: if (buffer_len(&stderr_buffer) > 0) {
1.230 djm 1618: len = atomicio(vwrite, fileno(stderr),
1619: buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
1.231 djm 1620: if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
1.11 markus 1621: error("Write failed flushing stderr buffer.");
1.231 djm 1622: else
1623: buffer_consume(&stderr_buffer, len);
1.11 markus 1624: }
1625:
1626: /* Clear and free any buffers. */
1627: memset(buf, 0, sizeof(buf));
1628: buffer_free(&stdin_buffer);
1629: buffer_free(&stdout_buffer);
1630: buffer_free(&stderr_buffer);
1631:
1632: /* Report bytes transferred, and transfer rates. */
1633: total_time = get_current_time() - start_time;
1.200 markus 1634: packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
1635: packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
1636: verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
1.229 djm 1637: (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
1.11 markus 1638: if (total_time > 0)
1.200 markus 1639: verbose("Bytes per second: sent %.1f, received %.1f",
1640: obytes / total_time, ibytes / total_time);
1.11 markus 1641: /* Return the exit status of the program. */
1642: debug("Exit status %d", exit_status);
1643: return exit_status;
1.15 markus 1644: }
1645:
1646: /*********/
1647:
1.77 itojun 1648: static void
1.94 markus 1649: client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1.15 markus 1650: {
1.42 markus 1651: u_int data_len;
1.15 markus 1652: char *data = packet_get_string(&data_len);
1.93 markus 1653: packet_check_eom();
1.15 markus 1654: buffer_append(&stdout_buffer, data, data_len);
1655: memset(data, 0, data_len);
1656: xfree(data);
1657: }
1.77 itojun 1658: static void
1.94 markus 1659: client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1.15 markus 1660: {
1.42 markus 1661: u_int data_len;
1.15 markus 1662: char *data = packet_get_string(&data_len);
1.93 markus 1663: packet_check_eom();
1.15 markus 1664: buffer_append(&stderr_buffer, data, data_len);
1665: memset(data, 0, data_len);
1666: xfree(data);
1667: }
1.77 itojun 1668: static void
1.94 markus 1669: client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1.15 markus 1670: {
1671: exit_status = packet_get_int();
1.93 markus 1672: packet_check_eom();
1.15 markus 1673: /* Acknowledge the exit. */
1674: packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1675: packet_send();
1676: /*
1677: * Must wait for packet to be sent since we are
1678: * exiting the loop.
1679: */
1680: packet_write_wait();
1681: /* Flag that we want to exit. */
1682: quit_pending = 1;
1683: }
1.115 markus 1684: static void
1685: client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1686: {
1687: Channel *c = NULL;
1688: int remote_id, sock;
1689:
1690: /* Read the remote channel number from the message. */
1691: remote_id = packet_get_int();
1692: packet_check_eom();
1693:
1694: /*
1695: * Get a connection to the local authentication agent (this may again
1696: * get forwarded).
1697: */
1698: sock = ssh_get_authentication_socket();
1699:
1700: /*
1701: * If we could not connect the agent, send an error message back to
1702: * the server. This should never happen unless the agent dies,
1703: * because authentication forwarding is only enabled if we have an
1704: * agent.
1705: */
1706: if (sock >= 0) {
1707: c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1708: -1, 0, 0, 0, "authentication agent connection", 1);
1709: c->remote_id = remote_id;
1710: c->force_drain = 1;
1711: }
1712: if (c == NULL) {
1713: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1714: packet_put_int(remote_id);
1715: } else {
1716: /* Send a confirmation to the remote host. */
1717: debug("Forwarding authentication connection.");
1718: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1719: packet_put_int(remote_id);
1720: packet_put_int(c->self);
1721: }
1722: packet_send();
1723: }
1.15 markus 1724:
1.77 itojun 1725: static Channel *
1.40 markus 1726: client_request_forwarded_tcpip(const char *request_type, int rchan)
1727: {
1.103 deraadt 1728: Channel *c = NULL;
1.40 markus 1729: char *listen_address, *originator_address;
1.208 djm 1730: u_short listen_port, originator_port;
1.40 markus 1731:
1732: /* Get rest of the packet */
1733: listen_address = packet_get_string(NULL);
1734: listen_port = packet_get_int();
1735: originator_address = packet_get_string(NULL);
1736: originator_port = packet_get_int();
1.93 markus 1737: packet_check_eom();
1.40 markus 1738:
1.191 djm 1739: debug("client_request_forwarded_tcpip: listen %s port %d, "
1740: "originator %s port %d", listen_address, listen_port,
1741: originator_address, originator_port);
1742:
1743: c = channel_connect_by_listen_address(listen_port,
1744: "forwarded-tcpip", originator_address);
1.40 markus 1745:
1746: xfree(originator_address);
1747: xfree(listen_address);
1748: return c;
1749: }
1750:
1.103 deraadt 1751: static Channel *
1.40 markus 1752: client_request_x11(const char *request_type, int rchan)
1753: {
1754: Channel *c = NULL;
1755: char *originator;
1.208 djm 1756: u_short originator_port;
1.67 markus 1757: int sock;
1.40 markus 1758:
1759: if (!options.forward_x11) {
1760: error("Warning: ssh server tried X11 forwarding.");
1.197 djm 1761: error("Warning: this is probably a break-in attempt by a "
1762: "malicious server.");
1.221 djm 1763: return NULL;
1764: }
1765: if (x11_refuse_time != 0 && time(NULL) >= x11_refuse_time) {
1766: verbose("Rejected X11 connection after ForwardX11Timeout "
1767: "expired");
1.40 markus 1768: return NULL;
1769: }
1770: originator = packet_get_string(NULL);
1771: if (datafellows & SSH_BUG_X11FWD) {
1772: debug2("buggy server: x11 request w/o originator_port");
1773: originator_port = 0;
1774: } else {
1775: originator_port = packet_get_int();
1776: }
1.93 markus 1777: packet_check_eom();
1.40 markus 1778: /* XXX check permission */
1.47 markus 1779: debug("client_request_x11: request from %s %d", originator,
1780: originator_port);
1.67 markus 1781: xfree(originator);
1.40 markus 1782: sock = x11_connect_display();
1.67 markus 1783: if (sock < 0)
1784: return NULL;
1785: c = channel_new("x11",
1786: SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1.110 markus 1787: CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1.82 markus 1788: c->force_drain = 1;
1.40 markus 1789: return c;
1790: }
1791:
1.103 deraadt 1792: static Channel *
1.40 markus 1793: client_request_agent(const char *request_type, int rchan)
1794: {
1795: Channel *c = NULL;
1.67 markus 1796: int sock;
1.40 markus 1797:
1798: if (!options.forward_agent) {
1799: error("Warning: ssh server tried agent forwarding.");
1.197 djm 1800: error("Warning: this is probably a break-in attempt by a "
1801: "malicious server.");
1.40 markus 1802: return NULL;
1803: }
1.177 stevesk 1804: sock = ssh_get_authentication_socket();
1.67 markus 1805: if (sock < 0)
1806: return NULL;
1807: c = channel_new("authentication agent connection",
1808: SSH_CHANNEL_OPEN, sock, sock, -1,
1.185 dtucker 1809: CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0,
1.110 markus 1810: "authentication agent connection", 1);
1.82 markus 1811: c->force_drain = 1;
1.40 markus 1812: return c;
1.180 djm 1813: }
1814:
1815: int
1816: client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
1817: {
1818: Channel *c;
1819: int fd;
1820:
1821: if (tun_mode == SSH_TUNMODE_NO)
1822: return 0;
1823:
1824: if (!compat20) {
1.207 stevesk 1825: error("Tunnel forwarding is not supported for protocol 1");
1.180 djm 1826: return -1;
1827: }
1828:
1829: debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
1830:
1831: /* Open local tunnel device */
1832: if ((fd = tun_open(local_tun, tun_mode)) == -1) {
1833: error("Tunnel device open failed.");
1834: return -1;
1835: }
1836:
1837: c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1838: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1);
1839: c->datagram = 1;
1840:
1841: packet_start(SSH2_MSG_CHANNEL_OPEN);
1842: packet_put_cstring("tun@openssh.com");
1843: packet_put_int(c->self);
1844: packet_put_int(c->local_window_max);
1845: packet_put_int(c->local_maxpacket);
1846: packet_put_int(tun_mode);
1847: packet_put_int(remote_tun);
1848: packet_send();
1849:
1850: return 0;
1.40 markus 1851: }
1852:
1.22 markus 1853: /* XXXX move to generic input handler */
1.77 itojun 1854: static void
1.94 markus 1855: client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1.22 markus 1856: {
1857: Channel *c = NULL;
1858: char *ctype;
1859: int rchan;
1.102 markus 1860: u_int rmaxpack, rwindow, len;
1.22 markus 1861:
1862: ctype = packet_get_string(&len);
1863: rchan = packet_get_int();
1864: rwindow = packet_get_int();
1865: rmaxpack = packet_get_int();
1866:
1.24 markus 1867: debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1.22 markus 1868: ctype, rchan, rwindow, rmaxpack);
1869:
1.40 markus 1870: if (strcmp(ctype, "forwarded-tcpip") == 0) {
1871: c = client_request_forwarded_tcpip(ctype, rchan);
1872: } else if (strcmp(ctype, "x11") == 0) {
1873: c = client_request_x11(ctype, rchan);
1874: } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1875: c = client_request_agent(ctype, rchan);
1.22 markus 1876: }
1877: /* XXX duplicate : */
1878: if (c != NULL) {
1879: debug("confirm %s", ctype);
1880: c->remote_id = rchan;
1881: c->remote_window = rwindow;
1882: c->remote_maxpacket = rmaxpack;
1.69 markus 1883: if (c->type != SSH_CHANNEL_CONNECTING) {
1884: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1885: packet_put_int(c->remote_id);
1886: packet_put_int(c->self);
1887: packet_put_int(c->local_window);
1888: packet_put_int(c->local_maxpacket);
1889: packet_send();
1890: }
1.22 markus 1891: } else {
1892: debug("failure %s", ctype);
1893: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1894: packet_put_int(rchan);
1895: packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1.66 markus 1896: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.69 markus 1897: packet_put_cstring("open failed");
1.66 markus 1898: packet_put_cstring("");
1899: }
1.22 markus 1900: packet_send();
1901: }
1902: xfree(ctype);
1903: }
1.77 itojun 1904: static void
1.94 markus 1905: client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1.48 markus 1906: {
1907: Channel *c = NULL;
1.123 djm 1908: int exitval, id, reply, success = 0;
1.48 markus 1909: char *rtype;
1910:
1911: id = packet_get_int();
1912: rtype = packet_get_string(NULL);
1913: reply = packet_get_char();
1914:
1915: debug("client_input_channel_req: channel %d rtype %s reply %d",
1916: id, rtype, reply);
1917:
1.128 djm 1918: if (id == -1) {
1919: error("client_input_channel_req: request for channel -1");
1920: } else if ((c = channel_lookup(id)) == NULL) {
1.197 djm 1921: error("client_input_channel_req: channel %d: "
1922: "unknown channel", id);
1.193 markus 1923: } else if (strcmp(rtype, "eow@openssh.com") == 0) {
1924: packet_check_eom();
1925: chan_rcvd_eow(c);
1.48 markus 1926: } else if (strcmp(rtype, "exit-status") == 0) {
1.123 djm 1927: exitval = packet_get_int();
1.217 djm 1928: if (c->ctl_chan != -1) {
1929: mux_exit_message(c, exitval);
1.215 djm 1930: success = 1;
1931: } else if (id == session_ident) {
1932: /* Record exit value of local session */
1.123 djm 1933: success = 1;
1934: exit_status = exitval;
1.215 djm 1935: } else {
1.218 djm 1936: /* Probably for a mux channel that has already closed */
1937: debug("%s: no sink for exit-status on channel %d",
1938: __func__, id);
1.123 djm 1939: }
1.93 markus 1940: packet_check_eom();
1.48 markus 1941: }
1.226 djm 1942: if (reply && c != NULL) {
1.48 markus 1943: packet_start(success ?
1944: SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1.205 markus 1945: packet_put_int(c->remote_id);
1.48 markus 1946: packet_send();
1947: }
1948: xfree(rtype);
1949: }
1.95 markus 1950: static void
1951: client_input_global_request(int type, u_int32_t seq, void *ctxt)
1952: {
1953: char *rtype;
1954: int want_reply;
1955: int success = 0;
1956:
1957: rtype = packet_get_string(NULL);
1958: want_reply = packet_get_char();
1.117 markus 1959: debug("client_input_global_request: rtype %s want_reply %d",
1960: rtype, want_reply);
1.95 markus 1961: if (want_reply) {
1962: packet_start(success ?
1963: SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1964: packet_send();
1965: packet_write_wait();
1966: }
1967: xfree(rtype);
1968: }
1.22 markus 1969:
1.123 djm 1970: void
1.129 deraadt 1971: client_session2_setup(int id, int want_tty, int want_subsystem,
1.190 djm 1972: const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
1.123 djm 1973: {
1974: int len;
1.132 djm 1975: Channel *c = NULL;
1.123 djm 1976:
1977: debug2("%s: id %d", __func__, id);
1978:
1.132 djm 1979: if ((c = channel_lookup(id)) == NULL)
1980: fatal("client_session2_setup: channel %d: unknown channel", id);
1.224 djm 1981:
1982: packet_set_interactive(want_tty,
1983: options.ip_qos_interactive, options.ip_qos_bulk);
1.132 djm 1984:
1.123 djm 1985: if (want_tty) {
1986: struct winsize ws;
1987:
1988: /* Store window size in the packet. */
1989: if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
1990: memset(&ws, 0, sizeof(ws));
1991:
1.190 djm 1992: channel_request_start(id, "pty-req", 1);
1.234 djm 1993: client_expect_confirm(id, "PTY allocation", CONFIRM_TTY);
1.123 djm 1994: packet_put_cstring(term != NULL ? term : "");
1.158 deraadt 1995: packet_put_int((u_int)ws.ws_col);
1996: packet_put_int((u_int)ws.ws_row);
1997: packet_put_int((u_int)ws.ws_xpixel);
1998: packet_put_int((u_int)ws.ws_ypixel);
1.194 djm 1999: if (tiop == NULL)
2000: tiop = get_saved_tio();
2001: tty_make_modes(-1, tiop);
1.123 djm 2002: packet_send();
2003: /* XXX wait for reply */
1.132 djm 2004: c->client_tty = 1;
1.123 djm 2005: }
2006:
2007: /* Transfer any environment variables from client to server */
1.126 djm 2008: if (options.num_send_env != 0 && env != NULL) {
1.123 djm 2009: int i, j, matched;
2010: char *name, *val;
2011:
2012: debug("Sending environment.");
1.126 djm 2013: for (i = 0; env[i] != NULL; i++) {
1.123 djm 2014: /* Split */
1.126 djm 2015: name = xstrdup(env[i]);
1.123 djm 2016: if ((val = strchr(name, '=')) == NULL) {
1.144 stevesk 2017: xfree(name);
1.123 djm 2018: continue;
2019: }
2020: *val++ = '\0';
2021:
2022: matched = 0;
2023: for (j = 0; j < options.num_send_env; j++) {
2024: if (match_pattern(name, options.send_env[j])) {
2025: matched = 1;
2026: break;
2027: }
2028: }
2029: if (!matched) {
2030: debug3("Ignored env %s", name);
1.144 stevesk 2031: xfree(name);
1.123 djm 2032: continue;
2033: }
2034:
2035: debug("Sending env %s = %s", name, val);
2036: channel_request_start(id, "env", 0);
2037: packet_put_cstring(name);
2038: packet_put_cstring(val);
2039: packet_send();
1.144 stevesk 2040: xfree(name);
1.123 djm 2041: }
2042: }
2043:
2044: len = buffer_len(cmd);
2045: if (len > 0) {
2046: if (len > 900)
2047: len = 900;
2048: if (want_subsystem) {
1.190 djm 2049: debug("Sending subsystem: %.*s",
2050: len, (u_char*)buffer_ptr(cmd));
2051: channel_request_start(id, "subsystem", 1);
1.234 djm 2052: client_expect_confirm(id, "subsystem", CONFIRM_CLOSE);
1.123 djm 2053: } else {
1.190 djm 2054: debug("Sending command: %.*s",
2055: len, (u_char*)buffer_ptr(cmd));
2056: channel_request_start(id, "exec", 1);
1.234 djm 2057: client_expect_confirm(id, "exec", CONFIRM_CLOSE);
1.123 djm 2058: }
2059: packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
2060: packet_send();
2061: } else {
1.190 djm 2062: channel_request_start(id, "shell", 1);
1.234 djm 2063: client_expect_confirm(id, "shell", CONFIRM_CLOSE);
1.123 djm 2064: packet_send();
2065: }
2066: }
2067:
1.77 itojun 2068: static void
1.49 itojun 2069: client_init_dispatch_20(void)
1.16 markus 2070: {
1.55 markus 2071: dispatch_init(&dispatch_protocol_error);
1.100 markus 2072:
1.16 markus 2073: dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
2074: dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
2075: dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
2076: dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1.22 markus 2077: dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1.16 markus 2078: dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2079: dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1.48 markus 2080: dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1.16 markus 2081: dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1.189 djm 2082: dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
2083: dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
1.95 markus 2084: dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1.55 markus 2085:
2086: /* rekeying */
2087: dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1.100 markus 2088:
2089: /* global request reply messages */
2090: dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
2091: dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1.16 markus 2092: }
1.197 djm 2093:
1.77 itojun 2094: static void
1.49 itojun 2095: client_init_dispatch_13(void)
1.15 markus 2096: {
2097: dispatch_init(NULL);
2098: dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
2099: dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
2100: dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
2101: dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2102: dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2103: dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2104: dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2105: dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2106: dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1.39 markus 2107:
2108: dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1.115 markus 2109: &client_input_agent_open : &deny_input_open);
1.39 markus 2110: dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2111: &x11_input_open : &deny_input_open);
1.15 markus 2112: }
1.197 djm 2113:
1.77 itojun 2114: static void
1.49 itojun 2115: client_init_dispatch_15(void)
1.15 markus 2116: {
2117: client_init_dispatch_13();
2118: dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2119: dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2120: }
1.197 djm 2121:
1.79 stevesk 2122: static void
1.49 itojun 2123: client_init_dispatch(void)
1.15 markus 2124: {
1.16 markus 2125: if (compat20)
2126: client_init_dispatch_20();
2127: else if (compat13)
1.15 markus 2128: client_init_dispatch_13();
2129: else
2130: client_init_dispatch_15();
1.232 djm 2131: }
2132:
2133: void
2134: client_stop_mux(void)
2135: {
2136: if (options.control_path != NULL && muxserver_sock != -1)
2137: unlink(options.control_path);
2138: /*
2139: * If we are in persist mode, signal that we should close when all
2140: * active channels are closed.
2141: */
1.235 ! djm 2142: if (options.control_persist) {
1.232 djm 2143: session_closed = 1;
1.235 ! djm 2144: setproctitle("[stopped mux]");
! 2145: }
1.113 markus 2146: }
2147:
2148: /* client specific fatal cleanup */
2149: void
1.114 markus 2150: cleanup_exit(int i)
1.113 markus 2151: {
1.233 djm 2152: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.113 markus 2153: leave_non_blocking();
1.192 djm 2154: if (options.control_path != NULL && muxserver_sock != -1)
1.123 djm 2155: unlink(options.control_path);
1.223 djm 2156: ssh_kill_proxy_command();
1.114 markus 2157: _exit(i);
1.1 deraadt 2158: }
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