Annotation of src/usr.bin/ssh/clientloop.c, Revision 1.242
1.242 ! dtucker 1: /* $OpenBSD: clientloop.c,v 1.241 2012/08/17 00:45:45 dtucker 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 */
1.190 djm 169: struct channel_reply_ctx {
170: const char *request_type;
1.234 djm 171: int id;
172: enum confirm_action action;
1.190 djm 173: };
174:
1.196 djm 175: /* Global request success/failure callbacks */
176: struct global_confirm {
177: TAILQ_ENTRY(global_confirm) entry;
178: global_confirm_cb *cb;
179: void *ctx;
180: int ref_count;
181: };
182: TAILQ_HEAD(global_confirms, global_confirm);
183: static struct global_confirms global_confirms =
184: TAILQ_HEAD_INITIALIZER(global_confirms);
185:
1.54 markus 186: /*XXX*/
187: extern Kex *xxx_kex;
188:
1.123 djm 189: void ssh_process_session2_setup(int, int, int, Buffer *);
190:
1.1 deraadt 191: /* Restores stdin to blocking mode. */
192:
1.77 itojun 193: static void
1.49 itojun 194: leave_non_blocking(void)
1.1 deraadt 195: {
1.11 markus 196: if (in_non_blocking_mode) {
1.125 djm 197: unset_nonblock(fileno(stdin));
1.11 markus 198: in_non_blocking_mode = 0;
199: }
1.1 deraadt 200: }
201:
1.11 markus 202: /* Puts stdin terminal in non-blocking mode. */
203:
1.77 itojun 204: static void
1.49 itojun 205: enter_non_blocking(void)
1.1 deraadt 206: {
1.11 markus 207: in_non_blocking_mode = 1;
1.124 djm 208: set_nonblock(fileno(stdin));
1.1 deraadt 209: }
210:
1.13 markus 211: /*
212: * Signal handler for the window change signal (SIGWINCH). This just sets a
213: * flag indicating that the window has changed.
214: */
1.157 deraadt 215: /*ARGSUSED */
1.77 itojun 216: static void
1.11 markus 217: window_change_handler(int sig)
1.1 deraadt 218: {
1.11 markus 219: received_window_change_signal = 1;
220: signal(SIGWINCH, window_change_handler);
1.1 deraadt 221: }
222:
1.13 markus 223: /*
224: * Signal handler for signals that cause the program to terminate. These
225: * signals must be trapped to restore terminal modes.
226: */
1.157 deraadt 227: /*ARGSUSED */
1.77 itojun 228: static void
1.11 markus 229: signal_handler(int sig)
1.1 deraadt 230: {
1.75 markus 231: received_signal = sig;
232: quit_pending = 1;
1.1 deraadt 233: }
234:
1.13 markus 235: /*
236: * Returns current time in seconds from Jan 1, 1970 with the maximum
237: * available resolution.
238: */
1.1 deraadt 239:
1.77 itojun 240: static double
1.49 itojun 241: get_current_time(void)
1.1 deraadt 242: {
1.11 markus 243: struct timeval tv;
244: gettimeofday(&tv, NULL);
245: return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
1.138 djm 246: }
247:
1.222 djm 248: /*
249: * Sets control_persist_exit_time to the absolute time when the
250: * backgrounded control master should exit due to expiry of the
251: * ControlPersist timeout. Sets it to 0 if we are not a backgrounded
252: * control master process, or if there is no ControlPersist timeout.
253: */
254: static void
255: set_control_persist_exit_time(void)
256: {
257: if (muxserver_sock == -1 || !options.control_persist
1.232 djm 258: || options.control_persist_timeout == 0) {
1.222 djm 259: /* not using a ControlPersist timeout */
260: control_persist_exit_time = 0;
1.232 djm 261: } else if (channel_still_open()) {
1.222 djm 262: /* some client connections are still open */
263: if (control_persist_exit_time > 0)
264: debug2("%s: cancel scheduled exit", __func__);
265: control_persist_exit_time = 0;
266: } else if (control_persist_exit_time <= 0) {
267: /* a client connection has recently closed */
268: control_persist_exit_time = time(NULL) +
269: (time_t)options.control_persist_timeout;
270: debug2("%s: schedule exit in %d seconds", __func__,
271: options.control_persist_timeout);
272: }
273: /* else we are already counting down to the timeout */
274: }
275:
1.238 dtucker 276: #define SSH_X11_VALID_DISPLAY_CHARS ":/.-_"
277: static int
278: client_x11_display_valid(const char *display)
279: {
280: size_t i, dlen;
281:
282: dlen = strlen(display);
283: for (i = 0; i < dlen; i++) {
284: if (!isalnum(display[i]) &&
285: strchr(SSH_X11_VALID_DISPLAY_CHARS, display[i]) == NULL) {
286: debug("Invalid character '%c' in DISPLAY", display[i]);
287: return 0;
288: }
289: }
290: return 1;
291: }
292:
1.138 djm 293: #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
294: void
295: client_x11_get_proto(const char *display, const char *xauth_path,
1.221 djm 296: u_int trusted, u_int timeout, char **_proto, char **_data)
1.138 djm 297: {
298: char cmd[1024];
299: char line[512];
300: char xdisplay[512];
301: static char proto[512], data[512];
302: FILE *f;
303: int got_data = 0, generated = 0, do_unlink = 0, i;
304: char *xauthdir, *xauthfile;
305: struct stat st;
1.221 djm 306: u_int now;
1.138 djm 307:
308: xauthdir = xauthfile = NULL;
309: *_proto = proto;
310: *_data = data;
311: proto[0] = data[0] = '\0';
312:
313: if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
314: debug("No xauth program.");
1.238 dtucker 315: } else if (!client_x11_display_valid(display)) {
316: logit("DISPLAY '%s' invalid, falling back to fake xauth data",
317: display);
1.138 djm 318: } else {
319: if (display == NULL) {
320: debug("x11_get_proto: DISPLAY not set");
321: return;
322: }
323: /*
324: * Handle FamilyLocal case where $DISPLAY does
325: * not match an authorization entry. For this we
326: * just try "xauth list unix:displaynum.screennum".
327: * XXX: "localhost" match to determine FamilyLocal
328: * is not perfect.
329: */
330: if (strncmp(display, "localhost:", 10) == 0) {
331: snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
332: display + 10);
333: display = xdisplay;
334: }
335: if (trusted == 0) {
336: xauthdir = xmalloc(MAXPATHLEN);
337: xauthfile = xmalloc(MAXPATHLEN);
1.225 djm 338: mktemp_proto(xauthdir, MAXPATHLEN);
1.138 djm 339: if (mkdtemp(xauthdir) != NULL) {
340: do_unlink = 1;
341: snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
342: xauthdir);
343: snprintf(cmd, sizeof(cmd),
344: "%s -f %s generate %s " SSH_X11_PROTO
1.221 djm 345: " untrusted timeout %u 2>" _PATH_DEVNULL,
346: xauth_path, xauthfile, display, timeout);
1.138 djm 347: debug2("x11_get_proto: %s", cmd);
348: if (system(cmd) == 0)
349: generated = 1;
1.221 djm 350: if (x11_refuse_time == 0) {
351: now = time(NULL) + 1;
352: if (UINT_MAX - timeout < now)
353: x11_refuse_time = UINT_MAX;
354: else
355: x11_refuse_time = now + timeout;
356: }
1.138 djm 357: }
358: }
1.181 markus 359:
360: /*
361: * When in untrusted mode, we read the cookie only if it was
362: * successfully generated as an untrusted one in the step
363: * above.
364: */
365: if (trusted || generated) {
366: snprintf(cmd, sizeof(cmd),
367: "%s %s%s list %s 2>" _PATH_DEVNULL,
368: xauth_path,
369: generated ? "-f " : "" ,
370: generated ? xauthfile : "",
371: display);
372: debug2("x11_get_proto: %s", cmd);
373: f = popen(cmd, "r");
374: if (f && fgets(line, sizeof(line), f) &&
375: sscanf(line, "%*s %511s %511s", proto, data) == 2)
376: got_data = 1;
377: if (f)
378: pclose(f);
379: } else
380: error("Warning: untrusted X11 forwarding setup failed: "
381: "xauth key data not generated");
1.138 djm 382: }
383:
384: if (do_unlink) {
385: unlink(xauthfile);
386: rmdir(xauthdir);
387: }
388: if (xauthdir)
389: xfree(xauthdir);
390: if (xauthfile)
391: xfree(xauthfile);
392:
393: /*
394: * If we didn't get authentication data, just make up some
395: * data. The forwarding code will check the validity of the
396: * response anyway, and substitute this data. The X11
397: * server, however, will ignore this fake data and use
398: * whatever authentication mechanisms it was using otherwise
399: * for the local connection.
400: */
401: if (!got_data) {
402: u_int32_t rnd = 0;
403:
404: logit("Warning: No xauth data; "
405: "using fake authentication data for X11 forwarding.");
406: strlcpy(proto, SSH_X11_PROTO, sizeof proto);
407: for (i = 0; i < 16; i++) {
408: if (i % 4 == 0)
409: rnd = arc4random();
410: snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
411: rnd & 0xff);
412: rnd >>= 8;
413: }
414: }
1.1 deraadt 415: }
416:
1.13 markus 417: /*
418: * This is called when the interactive is entered. This checks if there is
419: * an EOF coming on stdin. We must check this explicitly, as select() does
420: * not appear to wake up when redirecting from /dev/null.
421: */
1.1 deraadt 422:
1.77 itojun 423: static void
1.49 itojun 424: client_check_initial_eof_on_stdin(void)
1.1 deraadt 425: {
1.11 markus 426: int len;
427: char buf[1];
1.1 deraadt 428:
1.13 markus 429: /*
430: * If standard input is to be "redirected from /dev/null", we simply
431: * mark that we have seen an EOF and send an EOF message to the
432: * server. Otherwise, we try to read a single character; it appears
433: * that for some files, such /dev/null, select() never wakes up for
434: * read for this descriptor, which means that we never get EOF. This
435: * way we will get the EOF if stdin comes from /dev/null or similar.
436: */
1.11 markus 437: if (stdin_null_flag) {
438: /* Fake EOF on stdin. */
439: debug("Sending eof.");
440: stdin_eof = 1;
441: packet_start(SSH_CMSG_EOF);
442: packet_send();
443: } else {
444: enter_non_blocking();
445:
446: /* Check for immediate EOF on stdin. */
447: len = read(fileno(stdin), buf, 1);
448: if (len == 0) {
1.197 djm 449: /*
450: * EOF. Record that we have seen it and send
451: * EOF to server.
452: */
1.11 markus 453: debug("Sending eof.");
454: stdin_eof = 1;
455: packet_start(SSH_CMSG_EOF);
456: packet_send();
457: } else if (len > 0) {
1.13 markus 458: /*
459: * Got data. We must store the data in the buffer,
460: * and also process it as an escape character if
461: * appropriate.
462: */
1.195 djm 463: if ((u_char) buf[0] == escape_char1)
464: escape_pending1 = 1;
1.52 markus 465: else
1.11 markus 466: buffer_append(&stdin_buffer, buf, 1);
467: }
468: leave_non_blocking();
469: }
1.1 deraadt 470: }
471:
472:
1.13 markus 473: /*
474: * Make packets from buffered stdin data, and buffer them for sending to the
475: * connection.
476: */
1.1 deraadt 477:
1.77 itojun 478: static void
1.49 itojun 479: client_make_packets_from_stdin_data(void)
1.1 deraadt 480: {
1.42 markus 481: u_int len;
1.1 deraadt 482:
1.11 markus 483: /* Send buffered stdin data to the server. */
484: while (buffer_len(&stdin_buffer) > 0 &&
1.90 deraadt 485: packet_not_very_much_data_to_write()) {
1.11 markus 486: len = buffer_len(&stdin_buffer);
487: /* Keep the packets at reasonable size. */
488: if (len > packet_get_maxsize())
489: len = packet_get_maxsize();
490: packet_start(SSH_CMSG_STDIN_DATA);
491: packet_put_string(buffer_ptr(&stdin_buffer), len);
492: packet_send();
493: buffer_consume(&stdin_buffer, len);
494: /* If we have a pending EOF, send it now. */
495: if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
496: packet_start(SSH_CMSG_EOF);
497: packet_send();
498: }
1.1 deraadt 499: }
500: }
501:
1.13 markus 502: /*
503: * Checks if the client window has changed, and sends a packet about it to
504: * the server if so. The actual change is detected elsewhere (by a software
505: * interrupt on Unix); this just checks the flag and sends a message if
506: * appropriate.
507: */
1.1 deraadt 508:
1.77 itojun 509: static void
1.49 itojun 510: client_check_window_change(void)
1.1 deraadt 511: {
1.16 markus 512: struct winsize ws;
513:
514: if (! received_window_change_signal)
515: return;
516: /** XXX race */
517: received_window_change_signal = 0;
518:
1.37 markus 519: debug2("client_check_window_change: changed");
1.16 markus 520:
521: if (compat20) {
1.123 djm 522: channel_send_window_changes();
1.16 markus 523: } else {
1.123 djm 524: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
525: return;
1.16 markus 526: packet_start(SSH_CMSG_WINDOW_SIZE);
1.158 deraadt 527: packet_put_int((u_int)ws.ws_row);
528: packet_put_int((u_int)ws.ws_col);
529: packet_put_int((u_int)ws.ws_xpixel);
530: packet_put_int((u_int)ws.ws_ypixel);
1.16 markus 531: packet_send();
1.1 deraadt 532: }
533: }
534:
1.117 markus 535: static void
536: client_global_request_reply(int type, u_int32_t seq, void *ctxt)
537: {
1.196 djm 538: struct global_confirm *gc;
539:
540: if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
541: return;
542: if (gc->cb != NULL)
543: gc->cb(type, seq, gc->ctx);
544: if (--gc->ref_count <= 0) {
545: TAILQ_REMOVE(&global_confirms, gc, entry);
546: bzero(gc, sizeof(*gc));
547: xfree(gc);
548: }
549:
1.210 andreas 550: packet_set_alive_timeouts(0);
1.117 markus 551: }
552:
553: static void
554: server_alive_check(void)
555: {
1.210 andreas 556: if (packet_inc_alive_timeouts() > options.server_alive_count_max) {
1.228 djm 557: logit("Timeout, server %s not responding.", host);
1.176 markus 558: cleanup_exit(255);
559: }
1.117 markus 560: packet_start(SSH2_MSG_GLOBAL_REQUEST);
561: packet_put_cstring("keepalive@openssh.com");
562: packet_put_char(1); /* boolean: want reply */
563: packet_send();
1.196 djm 564: /* Insert an empty placeholder to maintain ordering */
565: client_register_global_confirm(NULL, NULL);
1.117 markus 566: }
567:
1.13 markus 568: /*
569: * Waits until the client can do something (some data becomes available on
570: * one of the file descriptors).
571: */
1.77 itojun 572: static void
1.46 markus 573: client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
1.130 avsm 574: int *maxfdp, u_int *nallocp, int rekeying)
1.11 markus 575: {
1.117 markus 576: struct timeval tv, *tvp;
1.222 djm 577: int timeout_secs;
1.240 djm 578: time_t minwait_secs = 0;
1.117 markus 579: int ret;
580:
1.46 markus 581: /* Add any selections by the channel mechanism. */
1.239 djm 582: channel_prepare_select(readsetp, writesetp, maxfdp, nallocp,
583: &minwait_secs, rekeying);
1.11 markus 584:
1.16 markus 585: if (!compat20) {
1.17 markus 586: /* Read from the connection, unless our buffers are full. */
1.16 markus 587: if (buffer_len(&stdout_buffer) < buffer_high &&
588: buffer_len(&stderr_buffer) < buffer_high &&
589: channel_not_very_much_buffered_data())
1.46 markus 590: FD_SET(connection_in, *readsetp);
1.17 markus 591: /*
592: * Read from stdin, unless we have seen EOF or have very much
593: * buffered data to send to the server.
594: */
595: if (!stdin_eof && packet_not_very_much_data_to_write())
1.46 markus 596: FD_SET(fileno(stdin), *readsetp);
1.17 markus 597:
598: /* Select stdout/stderr if have data in buffer. */
599: if (buffer_len(&stdout_buffer) > 0)
1.46 markus 600: FD_SET(fileno(stdout), *writesetp);
1.17 markus 601: if (buffer_len(&stderr_buffer) > 0)
1.46 markus 602: FD_SET(fileno(stderr), *writesetp);
1.16 markus 603: } else {
1.71 markus 604: /* channel_prepare_select could have closed the last channel */
1.84 markus 605: if (session_closed && !channel_still_open() &&
606: !packet_have_data_to_write()) {
607: /* clear mask since we did not call select() */
1.87 markus 608: memset(*readsetp, 0, *nallocp);
609: memset(*writesetp, 0, *nallocp);
1.84 markus 610: return;
1.71 markus 611: } else {
612: FD_SET(connection_in, *readsetp);
613: }
1.16 markus 614: }
1.11 markus 615:
616: /* Select server connection if have data to write to the server. */
617: if (packet_have_data_to_write())
1.46 markus 618: FD_SET(connection_out, *writesetp);
1.11 markus 619:
1.13 markus 620: /*
621: * Wait for something to happen. This will suspend the process until
622: * some selected descriptor can be read, written, or has some other
1.222 djm 623: * event pending, or a timeout expires.
1.13 markus 624: */
1.11 markus 625:
1.222 djm 626: timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */
627: if (options.server_alive_interval > 0 && compat20)
628: timeout_secs = options.server_alive_interval;
629: set_control_persist_exit_time();
630: if (control_persist_exit_time > 0) {
631: timeout_secs = MIN(timeout_secs,
632: control_persist_exit_time - time(NULL));
633: if (timeout_secs < 0)
634: timeout_secs = 0;
635: }
1.239 djm 636: if (minwait_secs != 0)
637: timeout_secs = MIN(timeout_secs, (int)minwait_secs);
1.222 djm 638: if (timeout_secs == INT_MAX)
1.117 markus 639: tvp = NULL;
1.129 deraadt 640: else {
1.222 djm 641: tv.tv_sec = timeout_secs;
1.117 markus 642: tv.tv_usec = 0;
643: tvp = &tv;
644: }
1.222 djm 645:
1.117 markus 646: ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
647: if (ret < 0) {
1.11 markus 648: char buf[100];
1.51 markus 649:
650: /*
651: * We have to clear the select masks, because we return.
652: * We have to return, because the mainloop checks for the flags
653: * set by the signal handlers.
654: */
1.87 markus 655: memset(*readsetp, 0, *nallocp);
656: memset(*writesetp, 0, *nallocp);
1.50 deraadt 657:
1.11 markus 658: if (errno == EINTR)
659: return;
660: /* Note: we might still have data in the buffers. */
661: snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
662: buffer_append(&stderr_buffer, buf, strlen(buf));
663: quit_pending = 1;
1.117 markus 664: } else if (ret == 0)
665: server_alive_check();
1.11 markus 666: }
667:
1.77 itojun 668: static void
1.31 markus 669: client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
1.1 deraadt 670: {
1.11 markus 671: /* Flush stdout and stderr buffers. */
1.31 markus 672: if (buffer_len(bout) > 0)
1.197 djm 673: atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
674: buffer_len(bout));
1.31 markus 675: if (buffer_len(berr) > 0)
1.197 djm 676: atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
677: buffer_len(berr));
1.11 markus 678:
1.233 djm 679: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.11 markus 680:
1.13 markus 681: /*
682: * Free (and clear) the buffer to reduce the amount of data that gets
683: * written to swap.
684: */
1.31 markus 685: buffer_free(bin);
686: buffer_free(bout);
687: buffer_free(berr);
1.11 markus 688:
689: /* Send the suspend signal to the program itself. */
690: kill(getpid(), SIGTSTP);
691:
1.132 djm 692: /* Reset window sizes in case they have changed */
693: received_window_change_signal = 1;
1.11 markus 694:
695: /* OK, we have been continued by the user. Reinitialize buffers. */
1.31 markus 696: buffer_init(bin);
697: buffer_init(bout);
698: buffer_init(berr);
1.11 markus 699:
1.233 djm 700: enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.11 markus 701: }
702:
1.77 itojun 703: static void
1.161 deraadt 704: client_process_net_input(fd_set *readset)
1.11 markus 705: {
1.212 andreas 706: int len, cont = 0;
1.17 markus 707: char buf[8192];
1.11 markus 708:
1.13 markus 709: /*
710: * Read input from the server, and add any such data to the buffer of
711: * the packet subsystem.
712: */
1.11 markus 713: if (FD_ISSET(connection_in, readset)) {
714: /* Read as much as possible. */
1.212 andreas 715: len = roaming_read(connection_in, buf, sizeof(buf), &cont);
716: if (len == 0 && cont == 0) {
1.197 djm 717: /*
718: * Received EOF. The remote host has closed the
719: * connection.
720: */
721: snprintf(buf, sizeof buf,
722: "Connection to %.300s closed by remote host.\r\n",
723: host);
1.1 deraadt 724: buffer_append(&stderr_buffer, buf, strlen(buf));
725: quit_pending = 1;
726: return;
1.11 markus 727: }
1.13 markus 728: /*
729: * There is a kernel bug on Solaris that causes select to
730: * sometimes wake up even though there is no data available.
731: */
1.53 millert 732: if (len < 0 && (errno == EAGAIN || errno == EINTR))
1.11 markus 733: len = 0;
734:
735: if (len < 0) {
1.197 djm 736: /*
737: * An error has encountered. Perhaps there is a
738: * network problem.
739: */
740: snprintf(buf, sizeof buf,
741: "Read from remote host %.300s: %.100s\r\n",
742: host, strerror(errno));
1.11 markus 743: buffer_append(&stderr_buffer, buf, strlen(buf));
744: quit_pending = 1;
745: return;
746: }
747: packet_process_incoming(buf, len);
748: }
1.17 markus 749: }
1.16 markus 750:
1.97 jakob 751: static void
1.190 djm 752: client_status_confirm(int type, Channel *c, void *ctx)
1.123 djm 753: {
1.190 djm 754: struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
755: char errmsg[256];
756: int tochan;
757:
1.234 djm 758: /*
759: * If a TTY was explicitly requested, then a failure to allocate
760: * one is fatal.
761: */
762: if (cr->action == CONFIRM_TTY &&
763: (options.request_tty == REQUEST_TTY_FORCE ||
764: options.request_tty == REQUEST_TTY_YES))
765: cr->action = CONFIRM_CLOSE;
766:
1.190 djm 767: /* XXX supress on mux _client_ quietmode */
768: tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
1.217 djm 769: c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
1.190 djm 770:
771: if (type == SSH2_MSG_CHANNEL_SUCCESS) {
772: debug2("%s request accepted on channel %d",
773: cr->request_type, c->self);
774: } else if (type == SSH2_MSG_CHANNEL_FAILURE) {
775: if (tochan) {
776: snprintf(errmsg, sizeof(errmsg),
777: "%s request failed\r\n", cr->request_type);
778: } else {
779: snprintf(errmsg, sizeof(errmsg),
780: "%s request failed on channel %d",
781: cr->request_type, c->self);
782: }
783: /* If error occurred on primary session channel, then exit */
1.234 djm 784: if (cr->action == CONFIRM_CLOSE && c->self == session_ident)
1.190 djm 785: fatal("%s", errmsg);
1.234 djm 786: /*
787: * If error occurred on mux client, append to
788: * their stderr.
789: */
790: if (tochan) {
791: buffer_append(&c->extended, errmsg,
792: strlen(errmsg));
793: } else
1.190 djm 794: error("%s", errmsg);
1.234 djm 795: if (cr->action == CONFIRM_TTY) {
796: /*
797: * If a TTY allocation error occurred, then arrange
798: * for the correct TTY to leave raw mode.
799: */
800: if (c->self == session_ident)
801: leave_raw_mode(0);
802: else
803: mux_tty_alloc_failed(c);
804: } else if (cr->action == CONFIRM_CLOSE) {
1.190 djm 805: chan_read_failed(c);
806: chan_write_failed(c);
807: }
808: }
809: xfree(cr);
810: }
811:
812: static void
813: client_abandon_status_confirm(Channel *c, void *ctx)
814: {
815: xfree(ctx);
816: }
1.129 deraadt 817:
1.236 djm 818: void
1.234 djm 819: client_expect_confirm(int id, const char *request,
820: enum confirm_action action)
1.190 djm 821: {
822: struct channel_reply_ctx *cr = xmalloc(sizeof(*cr));
1.123 djm 823:
1.190 djm 824: cr->request_type = request;
1.234 djm 825: cr->action = action;
1.123 djm 826:
1.190 djm 827: channel_register_status_confirm(id, client_status_confirm,
828: client_abandon_status_confirm, cr);
1.196 djm 829: }
830:
831: void
832: client_register_global_confirm(global_confirm_cb *cb, void *ctx)
833: {
1.201 djm 834: struct global_confirm *gc, *last_gc;
1.196 djm 835:
836: /* Coalesce identical callbacks */
1.201 djm 837: last_gc = TAILQ_LAST(&global_confirms, global_confirms);
838: if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
839: if (++last_gc->ref_count >= INT_MAX)
840: fatal("%s: last_gc->ref_count = %d",
841: __func__, last_gc->ref_count);
1.196 djm 842: return;
843: }
844:
845: gc = xmalloc(sizeof(*gc));
846: gc->cb = cb;
847: gc->ctx = ctx;
848: gc->ref_count = 1;
849: TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
1.123 djm 850: }
851:
852: static void
1.99 markus 853: process_cmdline(void)
1.97 jakob 854: {
855: void (*handler)(int);
1.135 djm 856: char *s, *cmd, *cancel_host;
1.237 markus 857: int delete = 0, local = 0, remote = 0, dynamic = 0;
858: int cancel_port, ok;
1.135 djm 859: Forward fwd;
1.97 jakob 860:
1.183 djm 861: bzero(&fwd, sizeof(fwd));
862: fwd.listen_host = fwd.connect_host = NULL;
863:
1.233 djm 864: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.101 markus 865: handler = signal(SIGINT, SIG_IGN);
1.99 markus 866: cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
1.97 jakob 867: if (s == NULL)
868: goto out;
1.179 tedu 869: while (isspace(*s))
1.97 jakob 870: s++;
1.121 djm 871: if (*s == '-')
872: s++; /* Skip cmdline '-', if any */
1.120 dtucker 873: if (*s == '\0')
1.97 jakob 874: goto out;
1.121 djm 875:
1.122 djm 876: if (*s == 'h' || *s == 'H' || *s == '?') {
1.121 djm 877: logit("Commands:");
1.164 djm 878: logit(" -L[bind_address:]port:host:hostport "
879: "Request local forward");
880: logit(" -R[bind_address:]port:host:hostport "
881: "Request remote forward");
1.204 stevesk 882: logit(" -D[bind_address:]port "
883: "Request dynamic forward");
1.237 markus 884: logit(" -KL[bind_address:]port "
885: "Cancel local forward");
1.165 stevesk 886: logit(" -KR[bind_address:]port "
1.164 djm 887: "Cancel remote forward");
1.237 markus 888: logit(" -KD[bind_address:]port "
889: "Cancel dynamic forward");
1.146 reyk 890: if (!options.permit_local_command)
891: goto out;
1.164 djm 892: logit(" !args "
893: "Execute local command");
1.146 reyk 894: goto out;
895: }
896:
897: if (*s == '!' && options.permit_local_command) {
898: s++;
899: ssh_local_cmd(s);
1.121 djm 900: goto out;
901: }
902:
903: if (*s == 'K') {
904: delete = 1;
905: s++;
906: }
1.204 stevesk 907: if (*s == 'L')
908: local = 1;
909: else if (*s == 'R')
910: remote = 1;
911: else if (*s == 'D')
912: dynamic = 1;
913: else {
1.109 itojun 914: logit("Invalid command.");
1.97 jakob 915: goto out;
916: }
1.204 stevesk 917:
1.237 markus 918: if (delete && !compat20) {
1.109 itojun 919: logit("Not supported for SSH protocol version 1.");
1.97 jakob 920: goto out;
921: }
1.121 djm 922:
1.179 tedu 923: while (isspace(*++s))
924: ;
1.97 jakob 925:
1.217 djm 926: /* XXX update list of forwards in options */
1.121 djm 927: if (delete) {
1.135 djm 928: cancel_port = 0;
929: cancel_host = hpdelim(&s); /* may be NULL */
930: if (s != NULL) {
931: cancel_port = a2port(s);
932: cancel_host = cleanhostname(cancel_host);
933: } else {
934: cancel_port = a2port(cancel_host);
935: cancel_host = NULL;
1.121 djm 936: }
1.208 djm 937: if (cancel_port <= 0) {
1.135 djm 938: logit("Bad forwarding close port");
1.121 djm 939: goto out;
940: }
1.237 markus 941: if (remote)
942: ok = channel_request_rforward_cancel(cancel_host,
943: cancel_port) == 0;
944: else if (dynamic)
945: ok = channel_cancel_lport_listener(cancel_host,
946: cancel_port, 0, options.gateway_ports) > 0;
947: else
948: ok = channel_cancel_lport_listener(cancel_host,
949: cancel_port, CHANNEL_CANCEL_PORT_STATIC,
950: options.gateway_ports) > 0;
951: if (!ok) {
952: logit("Unkown port forwarding.");
953: goto out;
954: }
955: logit("Canceled forwarding.");
1.121 djm 956: } else {
1.209 djm 957: if (!parse_forward(&fwd, s, dynamic, remote)) {
1.121 djm 958: logit("Bad forwarding specification.");
959: goto out;
960: }
1.204 stevesk 961: if (local || dynamic) {
1.135 djm 962: if (channel_setup_local_fwd_listener(fwd.listen_host,
963: fwd.listen_port, fwd.connect_host,
964: fwd.connect_port, options.gateway_ports) < 0) {
1.121 djm 965: logit("Port forwarding failed.");
966: goto out;
967: }
1.135 djm 968: } else {
1.167 markus 969: if (channel_request_remote_forwarding(fwd.listen_host,
1.135 djm 970: fwd.listen_port, fwd.connect_host,
1.167 markus 971: fwd.connect_port) < 0) {
972: logit("Port forwarding failed.");
973: goto out;
974: }
1.135 djm 975: }
1.121 djm 976: logit("Forwarding port.");
977: }
978:
1.97 jakob 979: out:
980: signal(SIGINT, handler);
1.233 djm 981: enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.97 jakob 982: if (cmd)
983: xfree(cmd);
1.183 djm 984: if (fwd.listen_host != NULL)
985: xfree(fwd.listen_host);
986: if (fwd.connect_host != NULL)
987: xfree(fwd.connect_host);
1.97 jakob 988: }
989:
1.195 djm 990: /*
991: * Process the characters one by one, call with c==NULL for proto1 case.
992: */
1.77 itojun 993: static int
1.195 djm 994: process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
995: char *buf, int len)
1.31 markus 996: {
1.32 markus 997: char string[1024];
1.31 markus 998: pid_t pid;
999: int bytes = 0;
1.42 markus 1000: u_int i;
1001: u_char ch;
1.31 markus 1002: char *s;
1.195 djm 1003: int *escape_pendingp, escape_char;
1004: struct escape_filter_ctx *efc;
1.31 markus 1005:
1.195 djm 1006: if (c == NULL) {
1007: escape_pendingp = &escape_pending1;
1008: escape_char = escape_char1;
1009: } else {
1010: if (c->filter_ctx == NULL)
1011: return 0;
1012: efc = (struct escape_filter_ctx *)c->filter_ctx;
1013: escape_pendingp = &efc->escape_pending;
1014: escape_char = efc->escape_char;
1015: }
1016:
1.139 djm 1017: if (len <= 0)
1018: return (0);
1019:
1020: for (i = 0; i < (u_int)len; i++) {
1.31 markus 1021: /* Get one character at a time. */
1022: ch = buf[i];
1023:
1.195 djm 1024: if (*escape_pendingp) {
1.31 markus 1025: /* We have previously seen an escape character. */
1026: /* Clear the flag now. */
1.195 djm 1027: *escape_pendingp = 0;
1.31 markus 1028:
1029: /* Process the escaped character. */
1030: switch (ch) {
1031: case '.':
1032: /* Terminate the connection. */
1.195 djm 1033: snprintf(string, sizeof string, "%c.\r\n",
1034: escape_char);
1.32 markus 1035: buffer_append(berr, string, strlen(string));
1.31 markus 1036:
1.217 djm 1037: if (c && c->ctl_chan != -1) {
1.195 djm 1038: chan_read_failed(c);
1039: chan_write_failed(c);
1.241 dtucker 1040: mux_master_session_cleanup_cb(c->self,
1041: NULL);
1.195 djm 1042: return 0;
1043: } else
1044: quit_pending = 1;
1.31 markus 1045: return -1;
1046:
1047: case 'Z' - 64:
1.195 djm 1048: /* XXX support this for mux clients */
1.217 djm 1049: if (c && c->ctl_chan != -1) {
1.195 djm 1050: noescape:
1051: snprintf(string, sizeof string,
1052: "%c%c escape not available to "
1053: "multiplexed sessions\r\n",
1054: escape_char, ch);
1055: buffer_append(berr, string,
1056: strlen(string));
1057: continue;
1058: }
1.197 djm 1059: /* Suspend the program. Inform the user */
1.195 djm 1060: snprintf(string, sizeof string,
1061: "%c^Z [suspend ssh]\r\n", escape_char);
1.32 markus 1062: buffer_append(berr, string, strlen(string));
1.31 markus 1063:
1064: /* Restore terminal modes and suspend. */
1065: client_suspend_self(bin, bout, berr);
1066:
1067: /* We have been continued. */
1068: continue;
1069:
1.111 markus 1070: case 'B':
1071: if (compat20) {
1072: snprintf(string, sizeof string,
1073: "%cB\r\n", escape_char);
1074: buffer_append(berr, string,
1075: strlen(string));
1076: channel_request_start(session_ident,
1077: "break", 0);
1078: packet_put_int(1000);
1079: packet_send();
1080: }
1081: continue;
1082:
1.54 markus 1083: case 'R':
1.59 markus 1084: if (compat20) {
1085: if (datafellows & SSH_BUG_NOREKEY)
1.197 djm 1086: logit("Server does not "
1087: "support re-keying");
1.59 markus 1088: else
1089: need_rekeying = 1;
1090: }
1.54 markus 1091: continue;
1092:
1.242 ! dtucker 1093: case 'V':
! 1094: /* FALLTHROUGH */
! 1095: case 'v':
! 1096: if (c && c->ctl_chan != -1)
! 1097: goto noescape;
! 1098: if (!log_is_on_stderr()) {
! 1099: snprintf(string, sizeof string,
! 1100: "%c%c [Logging to syslog]\r\n",
! 1101: escape_char, ch);
! 1102: buffer_append(berr, string,
! 1103: strlen(string));
! 1104: continue;
! 1105: }
! 1106: if (ch == 'V' && options.log_level >
! 1107: SYSLOG_LEVEL_QUIET)
! 1108: log_change_level(--options.log_level);
! 1109: if (ch == 'v' && options.log_level <
! 1110: SYSLOG_LEVEL_DEBUG3)
! 1111: log_change_level(++options.log_level);
! 1112: snprintf(string, sizeof string,
! 1113: "%c%c [LogLevel %s]\r\n", escape_char, ch,
! 1114: log_level_name(options.log_level));
! 1115: buffer_append(berr, string, strlen(string));
! 1116: continue;
! 1117:
1.31 markus 1118: case '&':
1.217 djm 1119: if (c && c->ctl_chan != -1)
1.195 djm 1120: goto noescape;
1.31 markus 1121: /*
1.197 djm 1122: * Detach the program (continue to serve
1123: * connections, but put in background and no
1124: * more new connections).
1.31 markus 1125: */
1126: /* Restore tty modes. */
1.233 djm 1127: leave_raw_mode(
1128: options.request_tty == REQUEST_TTY_FORCE);
1.31 markus 1129:
1130: /* Stop listening for new connections. */
1.86 markus 1131: channel_stop_listening();
1.31 markus 1132:
1.86 markus 1133: snprintf(string, sizeof string,
1134: "%c& [backgrounded]\n", escape_char);
1135: buffer_append(berr, string, strlen(string));
1.31 markus 1136:
1137: /* Fork into background. */
1138: pid = fork();
1139: if (pid < 0) {
1140: error("fork: %.100s", strerror(errno));
1141: continue;
1142: }
1143: if (pid != 0) { /* This is the parent. */
1144: /* The parent just exits. */
1145: exit(0);
1146: }
1147: /* The child continues serving connections. */
1.86 markus 1148: if (compat20) {
1149: buffer_append(bin, "\004", 1);
1150: /* fake EOF on stdin */
1151: return -1;
1152: } else if (!stdin_eof) {
1153: /*
1.197 djm 1154: * Sending SSH_CMSG_EOF alone does not
1155: * always appear to be enough. So we
1156: * try to send an EOF character first.
1.86 markus 1157: */
1158: packet_start(SSH_CMSG_STDIN_DATA);
1159: packet_put_string("\004", 1);
1160: packet_send();
1161: /* Close stdin. */
1162: stdin_eof = 1;
1163: if (buffer_len(bin) == 0) {
1164: packet_start(SSH_CMSG_EOF);
1165: packet_send();
1166: }
1167: }
1168: continue;
1.31 markus 1169:
1170: case '?':
1.217 djm 1171: if (c && c->ctl_chan != -1) {
1.195 djm 1172: snprintf(string, sizeof string,
1173: "%c?\r\n\
1174: Supported escape sequences:\r\n\
1175: %c. - terminate session\r\n\
1176: %cB - send a BREAK to the remote system\r\n\
1177: %cR - Request rekey (SSH protocol 2 only)\r\n\
1178: %c# - list forwarded connections\r\n\
1179: %c? - this message\r\n\
1180: %c%c - send the escape character by typing it twice\r\n\
1181: (Note that escapes are only recognized immediately after newline.)\r\n",
1182: escape_char, escape_char,
1183: escape_char, escape_char,
1184: escape_char, escape_char,
1.206 djm 1185: escape_char, escape_char);
1.195 djm 1186: } else {
1187: snprintf(string, sizeof string,
1.31 markus 1188: "%c?\r\n\
1189: Supported escape sequences:\r\n\
1.195 djm 1190: %c. - terminate connection (and any multiplexed sessions)\r\n\
1191: %cB - send a BREAK to the remote system\r\n\
1192: %cC - open a command line\r\n\
1193: %cR - Request rekey (SSH protocol 2 only)\r\n\
1.242 ! dtucker 1194: %cV - Increase verbosity (LogLevel)\r\n\
! 1195: %cv - Decrease verbosity (LogLevel)\r\n\
1.195 djm 1196: %c^Z - suspend ssh\r\n\
1197: %c# - list forwarded connections\r\n\
1198: %c& - background ssh (when waiting for connections to terminate)\r\n\
1199: %c? - this message\r\n\
1200: %c%c - send the escape character by typing it twice\r\n\
1.31 markus 1201: (Note that escapes are only recognized immediately after newline.)\r\n",
1.242 ! dtucker 1202: escape_char, escape_char,
1.195 djm 1203: escape_char, escape_char,
1204: escape_char, escape_char,
1205: escape_char, escape_char,
1206: escape_char, escape_char,
1207: escape_char, escape_char,
1208: escape_char);
1209: }
1.32 markus 1210: buffer_append(berr, string, strlen(string));
1.31 markus 1211: continue;
1212:
1213: case '#':
1.195 djm 1214: snprintf(string, sizeof string, "%c#\r\n",
1215: escape_char);
1.32 markus 1216: buffer_append(berr, string, strlen(string));
1.31 markus 1217: s = channel_open_message();
1218: buffer_append(berr, s, strlen(s));
1219: xfree(s);
1.97 jakob 1220: continue;
1221:
1222: case 'C':
1.217 djm 1223: if (c && c->ctl_chan != -1)
1.206 djm 1224: goto noescape;
1.99 markus 1225: process_cmdline();
1.31 markus 1226: continue;
1227:
1228: default:
1229: if (ch != escape_char) {
1230: buffer_put_char(bin, escape_char);
1231: bytes++;
1232: }
1233: /* Escaped characters fall through here */
1234: break;
1235: }
1236: } else {
1237: /*
1.197 djm 1238: * The previous character was not an escape char.
1239: * Check if this is an escape.
1.31 markus 1240: */
1241: if (last_was_cr && ch == escape_char) {
1.197 djm 1242: /*
1243: * It is. Set the flag and continue to
1244: * next character.
1245: */
1.195 djm 1246: *escape_pendingp = 1;
1.31 markus 1247: continue;
1248: }
1249: }
1250:
1251: /*
1252: * Normal character. Record whether it was a newline,
1253: * and append it to the buffer.
1254: */
1255: last_was_cr = (ch == '\r' || ch == '\n');
1256: buffer_put_char(bin, ch);
1257: bytes++;
1258: }
1259: return bytes;
1260: }
1261:
1.77 itojun 1262: static void
1.161 deraadt 1263: client_process_input(fd_set *readset)
1.17 markus 1264: {
1.21 deraadt 1265: int len;
1.31 markus 1266: char buf[8192];
1.16 markus 1267:
1.11 markus 1268: /* Read input from stdin. */
1269: if (FD_ISSET(fileno(stdin), readset)) {
1270: /* Read as much as possible. */
1271: len = read(fileno(stdin), buf, sizeof(buf));
1.64 markus 1272: if (len < 0 && (errno == EAGAIN || errno == EINTR))
1273: return; /* we'll try again later */
1.11 markus 1274: if (len <= 0) {
1.13 markus 1275: /*
1276: * Received EOF or error. They are treated
1277: * similarly, except that an error message is printed
1278: * if it was an error condition.
1279: */
1.11 markus 1280: if (len < 0) {
1.197 djm 1281: snprintf(buf, sizeof buf, "read: %.100s\r\n",
1282: strerror(errno));
1.11 markus 1283: buffer_append(&stderr_buffer, buf, strlen(buf));
1284: }
1285: /* Mark that we have seen EOF. */
1286: stdin_eof = 1;
1.13 markus 1287: /*
1288: * Send an EOF message to the server unless there is
1289: * data in the buffer. If there is data in the
1290: * buffer, no message will be sent now. Code
1291: * elsewhere will send the EOF when the buffer
1292: * becomes empty if stdin_eof is set.
1293: */
1.11 markus 1294: if (buffer_len(&stdin_buffer) == 0) {
1.1 deraadt 1295: packet_start(SSH_CMSG_EOF);
1296: packet_send();
1.11 markus 1297: }
1.195 djm 1298: } else if (escape_char1 == SSH_ESCAPECHAR_NONE) {
1.13 markus 1299: /*
1300: * Normal successful read, and no escape character.
1301: * Just append the data to buffer.
1302: */
1.11 markus 1303: buffer_append(&stdin_buffer, buf, len);
1304: } else {
1.13 markus 1305: /*
1.197 djm 1306: * Normal, successful read. But we have an escape
1307: * character and have to process the characters one
1308: * by one.
1.13 markus 1309: */
1.195 djm 1310: if (process_escapes(NULL, &stdin_buffer,
1311: &stdout_buffer, &stderr_buffer, buf, len) == -1)
1.31 markus 1312: return;
1.11 markus 1313: }
1314: }
1315: }
1316:
1.77 itojun 1317: static void
1.161 deraadt 1318: client_process_output(fd_set *writeset)
1.11 markus 1319: {
1320: int len;
1321: char buf[100];
1.1 deraadt 1322:
1.11 markus 1323: /* Write buffered output to stdout. */
1324: if (FD_ISSET(fileno(stdout), writeset)) {
1325: /* Write as much data as possible. */
1326: len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1.14 deraadt 1327: buffer_len(&stdout_buffer));
1.11 markus 1328: if (len <= 0) {
1.64 markus 1329: if (errno == EINTR || errno == EAGAIN)
1.11 markus 1330: len = 0;
1331: else {
1.13 markus 1332: /*
1333: * An error or EOF was encountered. Put an
1334: * error message to stderr buffer.
1335: */
1.197 djm 1336: snprintf(buf, sizeof buf,
1337: "write stdout: %.50s\r\n", strerror(errno));
1.11 markus 1338: buffer_append(&stderr_buffer, buf, strlen(buf));
1339: quit_pending = 1;
1340: return;
1341: }
1342: }
1343: /* Consume printed data from the buffer. */
1344: buffer_consume(&stdout_buffer, len);
1345: }
1346: /* Write buffered output to stderr. */
1347: if (FD_ISSET(fileno(stderr), writeset)) {
1348: /* Write as much data as possible. */
1349: len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1.14 deraadt 1350: buffer_len(&stderr_buffer));
1.11 markus 1351: if (len <= 0) {
1.64 markus 1352: if (errno == EINTR || errno == EAGAIN)
1.11 markus 1353: len = 0;
1354: else {
1.197 djm 1355: /*
1356: * EOF or error, but can't even print
1357: * error message.
1358: */
1.11 markus 1359: quit_pending = 1;
1360: return;
1361: }
1362: }
1363: /* Consume printed characters from the buffer. */
1364: buffer_consume(&stderr_buffer, len);
1365: }
1.1 deraadt 1366: }
1367:
1.13 markus 1368: /*
1.15 markus 1369: * Get packets from the connection input buffer, and process them as long as
1370: * there are packets available.
1371: *
1372: * Any unknown packets received during the actual
1373: * session cause the session to terminate. This is
1374: * intended to make debugging easier since no
1375: * confirmations are sent. Any compatible protocol
1376: * extensions must be negotiated during the
1377: * preparatory phase.
1378: */
1379:
1.77 itojun 1380: static void
1.49 itojun 1381: client_process_buffered_input_packets(void)
1.15 markus 1382: {
1.197 djm 1383: dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
1384: compat20 ? xxx_kex : NULL);
1.15 markus 1385: }
1386:
1.31 markus 1387: /* scan buf[] for '~' before sending data to the peer */
1.30 markus 1388:
1.195 djm 1389: /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1390: void *
1391: client_new_escape_filter_ctx(int escape_char)
1392: {
1393: struct escape_filter_ctx *ret;
1394:
1395: ret = xmalloc(sizeof(*ret));
1396: ret->escape_pending = 0;
1397: ret->escape_char = escape_char;
1398: return (void *)ret;
1399: }
1400:
1.198 djm 1401: /* Free the escape filter context on channel free */
1402: void
1403: client_filter_cleanup(int cid, void *ctx)
1404: {
1405: xfree(ctx);
1406: }
1407:
1.195 djm 1408: int
1409: client_simple_escape_filter(Channel *c, char *buf, int len)
1.30 markus 1410: {
1.190 djm 1411: if (c->extended_usage != CHAN_EXTENDED_WRITE)
1412: return 0;
1413:
1.195 djm 1414: return process_escapes(c, &c->input, &c->output, &c->extended,
1415: buf, len);
1.30 markus 1416: }
1417:
1.77 itojun 1418: static void
1.60 markus 1419: client_channel_closed(int id, void *arg)
1420: {
1.83 markus 1421: channel_cancel_cleanup(id);
1.60 markus 1422: session_closed = 1;
1.233 djm 1423: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.60 markus 1424: }
1425:
1.15 markus 1426: /*
1.13 markus 1427: * Implements the interactive session with the server. This is called after
1428: * the user has been authenticated, and a command has been started on the
1.72 stevesk 1429: * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1430: * used as an escape character for terminating or suspending the session.
1.13 markus 1431: */
1.1 deraadt 1432:
1.20 markus 1433: int
1.30 markus 1434: client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1.1 deraadt 1435: {
1.46 markus 1436: fd_set *readset = NULL, *writeset = NULL;
1.11 markus 1437: double start_time, total_time;
1.130 avsm 1438: int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1.200 markus 1439: u_int64_t ibytes, obytes;
1.130 avsm 1440: u_int nalloc = 0;
1.11 markus 1441: char buf[100];
1442:
1443: debug("Entering interactive session.");
1444:
1445: start_time = get_current_time();
1446:
1447: /* Initialize variables. */
1.195 djm 1448: escape_pending1 = 0;
1.11 markus 1449: last_was_cr = 1;
1450: exit_status = -1;
1451: stdin_eof = 0;
1452: buffer_high = 64 * 1024;
1453: connection_in = packet_get_connection_in();
1454: connection_out = packet_get_connection_out();
1.46 markus 1455: max_fd = MAX(connection_in, connection_out);
1456:
1457: if (!compat20) {
1.63 markus 1458: /* enable nonblocking unless tty */
1459: if (!isatty(fileno(stdin)))
1460: set_nonblock(fileno(stdin));
1461: if (!isatty(fileno(stdout)))
1462: set_nonblock(fileno(stdout));
1463: if (!isatty(fileno(stderr)))
1464: set_nonblock(fileno(stderr));
1.46 markus 1465: max_fd = MAX(max_fd, fileno(stdin));
1466: max_fd = MAX(max_fd, fileno(stdout));
1467: max_fd = MAX(max_fd, fileno(stderr));
1468: }
1.11 markus 1469: quit_pending = 0;
1.195 djm 1470: escape_char1 = escape_char_arg;
1.11 markus 1471:
1472: /* Initialize buffers. */
1473: buffer_init(&stdin_buffer);
1474: buffer_init(&stdout_buffer);
1475: buffer_init(&stderr_buffer);
1476:
1.15 markus 1477: client_init_dispatch();
1478:
1.105 markus 1479: /*
1480: * Set signal handlers, (e.g. to restore non-blocking mode)
1481: * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1482: */
1.131 djm 1483: if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1484: signal(SIGHUP, signal_handler);
1.105 markus 1485: if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1486: signal(SIGINT, signal_handler);
1487: if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1488: signal(SIGQUIT, signal_handler);
1489: if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1490: signal(SIGTERM, signal_handler);
1.132 djm 1491: signal(SIGWINCH, window_change_handler);
1.11 markus 1492:
1493: if (have_pty)
1.233 djm 1494: enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.11 markus 1495:
1.48 markus 1496: if (compat20) {
1497: session_ident = ssh2_chan_id;
1.232 djm 1498: if (session_ident != -1) {
1499: if (escape_char_arg != SSH_ESCAPECHAR_NONE) {
1500: channel_register_filter(session_ident,
1501: client_simple_escape_filter, NULL,
1502: client_filter_cleanup,
1503: client_new_escape_filter_ctx(
1504: escape_char_arg));
1505: }
1.60 markus 1506: channel_register_cleanup(session_ident,
1.143 djm 1507: client_channel_closed, 0);
1.232 djm 1508: }
1.48 markus 1509: } else {
1510: /* Check if we should immediately send eof on stdin. */
1.16 markus 1511: client_check_initial_eof_on_stdin();
1.48 markus 1512: }
1.30 markus 1513:
1.11 markus 1514: /* Main loop of the client for the interactive session mode. */
1515: while (!quit_pending) {
1516:
1.13 markus 1517: /* Process buffered packets sent by the server. */
1.11 markus 1518: client_process_buffered_input_packets();
1519:
1.60 markus 1520: if (compat20 && session_closed && !channel_still_open())
1521: break;
1522:
1.56 markus 1523: rekeying = (xxx_kex != NULL && !xxx_kex->done);
1.16 markus 1524:
1.56 markus 1525: if (rekeying) {
1526: debug("rekeying in progress");
1527: } else {
1528: /*
1529: * Make packets of buffered stdin data, and buffer
1530: * them for sending to the server.
1531: */
1532: if (!compat20)
1533: client_make_packets_from_stdin_data();
1.11 markus 1534:
1.56 markus 1535: /*
1536: * Make packets from buffered channel data, and
1537: * enqueue them for sending to the server.
1538: */
1539: if (packet_not_very_much_data_to_write())
1540: channel_output_poll();
1.11 markus 1541:
1.56 markus 1542: /*
1543: * Check if the window size has changed, and buffer a
1544: * message about it to the server if so.
1545: */
1546: client_check_window_change();
1.11 markus 1547:
1.56 markus 1548: if (quit_pending)
1549: break;
1550: }
1.13 markus 1551: /*
1552: * Wait until we have something to do (something becomes
1553: * available on one of the descriptors).
1554: */
1.81 markus 1555: max_fd2 = max_fd;
1.56 markus 1556: client_wait_until_can_do_something(&readset, &writeset,
1.81 markus 1557: &max_fd2, &nalloc, rekeying);
1.11 markus 1558:
1559: if (quit_pending)
1560: break;
1561:
1.56 markus 1562: /* Do channel operations unless rekeying in progress. */
1563: if (!rekeying) {
1564: channel_after_select(readset, writeset);
1.108 markus 1565: if (need_rekeying || packet_need_rekeying()) {
1566: debug("need rekeying");
1.56 markus 1567: xxx_kex->done = 0;
1568: kex_send_kexinit(xxx_kex);
1569: need_rekeying = 0;
1570: }
1571: }
1.11 markus 1572:
1.17 markus 1573: /* Buffer input from the connection. */
1.46 markus 1574: client_process_net_input(readset);
1.17 markus 1575:
1576: if (quit_pending)
1577: break;
1.11 markus 1578:
1.17 markus 1579: if (!compat20) {
1580: /* Buffer data from stdin */
1.46 markus 1581: client_process_input(readset);
1.17 markus 1582: /*
1583: * Process output to stdout and stderr. Output to
1584: * the connection is processed elsewhere (above).
1585: */
1.46 markus 1586: client_process_output(writeset);
1.214 andreas 1587: }
1588:
1589: if (session_resumed) {
1590: connection_in = packet_get_connection_in();
1591: connection_out = packet_get_connection_out();
1592: max_fd = MAX(max_fd, connection_out);
1593: max_fd = MAX(max_fd, connection_in);
1594: session_resumed = 0;
1.17 markus 1595: }
1.11 markus 1596:
1.197 djm 1597: /*
1598: * Send as much buffered packet data as possible to the
1599: * sender.
1600: */
1.46 markus 1601: if (FD_ISSET(connection_out, writeset))
1.11 markus 1602: packet_write_poll();
1.222 djm 1603:
1604: /*
1605: * If we are a backgrounded control master, and the
1606: * timeout has expired without any active client
1607: * connections, then quit.
1608: */
1609: if (control_persist_exit_time > 0) {
1610: if (time(NULL) >= control_persist_exit_time) {
1611: debug("ControlPersist timeout expired");
1612: break;
1613: }
1614: }
1.11 markus 1615: }
1.46 markus 1616: if (readset)
1617: xfree(readset);
1618: if (writeset)
1619: xfree(writeset);
1.11 markus 1620:
1621: /* Terminate the session. */
1622:
1623: /* Stop watching for window change. */
1.132 djm 1624: signal(SIGWINCH, SIG_DFL);
1.211 andreas 1625:
1.213 stevesk 1626: if (compat20) {
1627: packet_start(SSH2_MSG_DISCONNECT);
1628: packet_put_int(SSH2_DISCONNECT_BY_APPLICATION);
1629: packet_put_cstring("disconnected by user");
1.219 djm 1630: packet_put_cstring(""); /* language tag */
1.213 stevesk 1631: packet_send();
1632: packet_write_wait();
1633: }
1.11 markus 1634:
1.76 markus 1635: channel_free_all();
1.11 markus 1636:
1.75 markus 1637: if (have_pty)
1.233 djm 1638: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.75 markus 1639:
1640: /* restore blocking io */
1641: if (!isatty(fileno(stdin)))
1642: unset_nonblock(fileno(stdin));
1643: if (!isatty(fileno(stdout)))
1644: unset_nonblock(fileno(stdout));
1645: if (!isatty(fileno(stderr)))
1646: unset_nonblock(fileno(stderr));
1.116 dtucker 1647:
1648: /*
1649: * If there was no shell or command requested, there will be no remote
1650: * exit status to be returned. In that case, clear error code if the
1651: * connection was deliberately terminated at this end.
1652: */
1653: if (no_shell_flag && received_signal == SIGTERM) {
1654: received_signal = 0;
1655: exit_status = 0;
1656: }
1.75 markus 1657:
1.113 markus 1658: if (received_signal)
1.89 itojun 1659: fatal("Killed by signal %d.", (int) received_signal);
1.75 markus 1660:
1.13 markus 1661: /*
1662: * In interactive mode (with pseudo tty) display a message indicating
1663: * that the connection has been closed.
1664: */
1.11 markus 1665: if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1.197 djm 1666: snprintf(buf, sizeof buf,
1667: "Connection to %.64s closed.\r\n", host);
1.11 markus 1668: buffer_append(&stderr_buffer, buf, strlen(buf));
1669: }
1.70 markus 1670:
1.11 markus 1671: /* Output any buffered data for stdout. */
1.231 djm 1672: if (buffer_len(&stdout_buffer) > 0) {
1.230 djm 1673: len = atomicio(vwrite, fileno(stdout),
1674: buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer));
1.231 djm 1675: if (len < 0 || (u_int)len != buffer_len(&stdout_buffer))
1.11 markus 1676: error("Write failed flushing stdout buffer.");
1.231 djm 1677: else
1678: buffer_consume(&stdout_buffer, len);
1.11 markus 1679: }
1680:
1681: /* Output any buffered data for stderr. */
1.231 djm 1682: if (buffer_len(&stderr_buffer) > 0) {
1.230 djm 1683: len = atomicio(vwrite, fileno(stderr),
1684: buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
1.231 djm 1685: if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
1.11 markus 1686: error("Write failed flushing stderr buffer.");
1.231 djm 1687: else
1688: buffer_consume(&stderr_buffer, len);
1.11 markus 1689: }
1690:
1691: /* Clear and free any buffers. */
1692: memset(buf, 0, sizeof(buf));
1693: buffer_free(&stdin_buffer);
1694: buffer_free(&stdout_buffer);
1695: buffer_free(&stderr_buffer);
1696:
1697: /* Report bytes transferred, and transfer rates. */
1698: total_time = get_current_time() - start_time;
1.200 markus 1699: packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
1700: packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
1701: verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
1.229 djm 1702: (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
1.11 markus 1703: if (total_time > 0)
1.200 markus 1704: verbose("Bytes per second: sent %.1f, received %.1f",
1705: obytes / total_time, ibytes / total_time);
1.11 markus 1706: /* Return the exit status of the program. */
1707: debug("Exit status %d", exit_status);
1708: return exit_status;
1.15 markus 1709: }
1710:
1711: /*********/
1712:
1.77 itojun 1713: static void
1.94 markus 1714: client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1.15 markus 1715: {
1.42 markus 1716: u_int data_len;
1.15 markus 1717: char *data = packet_get_string(&data_len);
1.93 markus 1718: packet_check_eom();
1.15 markus 1719: buffer_append(&stdout_buffer, data, data_len);
1720: memset(data, 0, data_len);
1721: xfree(data);
1722: }
1.77 itojun 1723: static void
1.94 markus 1724: client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1.15 markus 1725: {
1.42 markus 1726: u_int data_len;
1.15 markus 1727: char *data = packet_get_string(&data_len);
1.93 markus 1728: packet_check_eom();
1.15 markus 1729: buffer_append(&stderr_buffer, data, data_len);
1730: memset(data, 0, data_len);
1731: xfree(data);
1732: }
1.77 itojun 1733: static void
1.94 markus 1734: client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1.15 markus 1735: {
1736: exit_status = packet_get_int();
1.93 markus 1737: packet_check_eom();
1.15 markus 1738: /* Acknowledge the exit. */
1739: packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1740: packet_send();
1741: /*
1742: * Must wait for packet to be sent since we are
1743: * exiting the loop.
1744: */
1745: packet_write_wait();
1746: /* Flag that we want to exit. */
1747: quit_pending = 1;
1748: }
1.115 markus 1749: static void
1750: client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1751: {
1752: Channel *c = NULL;
1753: int remote_id, sock;
1754:
1755: /* Read the remote channel number from the message. */
1756: remote_id = packet_get_int();
1757: packet_check_eom();
1758:
1759: /*
1760: * Get a connection to the local authentication agent (this may again
1761: * get forwarded).
1762: */
1763: sock = ssh_get_authentication_socket();
1764:
1765: /*
1766: * If we could not connect the agent, send an error message back to
1767: * the server. This should never happen unless the agent dies,
1768: * because authentication forwarding is only enabled if we have an
1769: * agent.
1770: */
1771: if (sock >= 0) {
1772: c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1773: -1, 0, 0, 0, "authentication agent connection", 1);
1774: c->remote_id = remote_id;
1775: c->force_drain = 1;
1776: }
1777: if (c == NULL) {
1778: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1779: packet_put_int(remote_id);
1780: } else {
1781: /* Send a confirmation to the remote host. */
1782: debug("Forwarding authentication connection.");
1783: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1784: packet_put_int(remote_id);
1785: packet_put_int(c->self);
1786: }
1787: packet_send();
1788: }
1.15 markus 1789:
1.77 itojun 1790: static Channel *
1.40 markus 1791: client_request_forwarded_tcpip(const char *request_type, int rchan)
1792: {
1.103 deraadt 1793: Channel *c = NULL;
1.40 markus 1794: char *listen_address, *originator_address;
1.208 djm 1795: u_short listen_port, originator_port;
1.40 markus 1796:
1797: /* Get rest of the packet */
1798: listen_address = packet_get_string(NULL);
1799: listen_port = packet_get_int();
1800: originator_address = packet_get_string(NULL);
1801: originator_port = packet_get_int();
1.93 markus 1802: packet_check_eom();
1.40 markus 1803:
1.191 djm 1804: debug("client_request_forwarded_tcpip: listen %s port %d, "
1805: "originator %s port %d", listen_address, listen_port,
1806: originator_address, originator_port);
1807:
1808: c = channel_connect_by_listen_address(listen_port,
1809: "forwarded-tcpip", originator_address);
1.40 markus 1810:
1811: xfree(originator_address);
1812: xfree(listen_address);
1813: return c;
1814: }
1815:
1.103 deraadt 1816: static Channel *
1.40 markus 1817: client_request_x11(const char *request_type, int rchan)
1818: {
1819: Channel *c = NULL;
1820: char *originator;
1.208 djm 1821: u_short originator_port;
1.67 markus 1822: int sock;
1.40 markus 1823:
1824: if (!options.forward_x11) {
1825: error("Warning: ssh server tried X11 forwarding.");
1.197 djm 1826: error("Warning: this is probably a break-in attempt by a "
1827: "malicious server.");
1.221 djm 1828: return NULL;
1829: }
1830: if (x11_refuse_time != 0 && time(NULL) >= x11_refuse_time) {
1831: verbose("Rejected X11 connection after ForwardX11Timeout "
1832: "expired");
1.40 markus 1833: return NULL;
1834: }
1835: originator = packet_get_string(NULL);
1836: if (datafellows & SSH_BUG_X11FWD) {
1837: debug2("buggy server: x11 request w/o originator_port");
1838: originator_port = 0;
1839: } else {
1840: originator_port = packet_get_int();
1841: }
1.93 markus 1842: packet_check_eom();
1.40 markus 1843: /* XXX check permission */
1.47 markus 1844: debug("client_request_x11: request from %s %d", originator,
1845: originator_port);
1.67 markus 1846: xfree(originator);
1.40 markus 1847: sock = x11_connect_display();
1.67 markus 1848: if (sock < 0)
1849: return NULL;
1850: c = channel_new("x11",
1851: SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1.110 markus 1852: CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1.82 markus 1853: c->force_drain = 1;
1.40 markus 1854: return c;
1855: }
1856:
1.103 deraadt 1857: static Channel *
1.40 markus 1858: client_request_agent(const char *request_type, int rchan)
1859: {
1860: Channel *c = NULL;
1.67 markus 1861: int sock;
1.40 markus 1862:
1863: if (!options.forward_agent) {
1864: error("Warning: ssh server tried agent forwarding.");
1.197 djm 1865: error("Warning: this is probably a break-in attempt by a "
1866: "malicious server.");
1.40 markus 1867: return NULL;
1868: }
1.177 stevesk 1869: sock = ssh_get_authentication_socket();
1.67 markus 1870: if (sock < 0)
1871: return NULL;
1872: c = channel_new("authentication agent connection",
1873: SSH_CHANNEL_OPEN, sock, sock, -1,
1.185 dtucker 1874: CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0,
1.110 markus 1875: "authentication agent connection", 1);
1.82 markus 1876: c->force_drain = 1;
1.40 markus 1877: return c;
1.180 djm 1878: }
1879:
1880: int
1881: client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
1882: {
1883: Channel *c;
1884: int fd;
1885:
1886: if (tun_mode == SSH_TUNMODE_NO)
1887: return 0;
1888:
1889: if (!compat20) {
1.207 stevesk 1890: error("Tunnel forwarding is not supported for protocol 1");
1.180 djm 1891: return -1;
1892: }
1893:
1894: debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
1895:
1896: /* Open local tunnel device */
1897: if ((fd = tun_open(local_tun, tun_mode)) == -1) {
1898: error("Tunnel device open failed.");
1899: return -1;
1900: }
1901:
1902: c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1903: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1);
1904: c->datagram = 1;
1905:
1906: packet_start(SSH2_MSG_CHANNEL_OPEN);
1907: packet_put_cstring("tun@openssh.com");
1908: packet_put_int(c->self);
1909: packet_put_int(c->local_window_max);
1910: packet_put_int(c->local_maxpacket);
1911: packet_put_int(tun_mode);
1912: packet_put_int(remote_tun);
1913: packet_send();
1914:
1915: return 0;
1.40 markus 1916: }
1917:
1.22 markus 1918: /* XXXX move to generic input handler */
1.77 itojun 1919: static void
1.94 markus 1920: client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1.22 markus 1921: {
1922: Channel *c = NULL;
1923: char *ctype;
1924: int rchan;
1.102 markus 1925: u_int rmaxpack, rwindow, len;
1.22 markus 1926:
1927: ctype = packet_get_string(&len);
1928: rchan = packet_get_int();
1929: rwindow = packet_get_int();
1930: rmaxpack = packet_get_int();
1931:
1.24 markus 1932: debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1.22 markus 1933: ctype, rchan, rwindow, rmaxpack);
1934:
1.40 markus 1935: if (strcmp(ctype, "forwarded-tcpip") == 0) {
1936: c = client_request_forwarded_tcpip(ctype, rchan);
1937: } else if (strcmp(ctype, "x11") == 0) {
1938: c = client_request_x11(ctype, rchan);
1939: } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1940: c = client_request_agent(ctype, rchan);
1.22 markus 1941: }
1942: /* XXX duplicate : */
1943: if (c != NULL) {
1944: debug("confirm %s", ctype);
1945: c->remote_id = rchan;
1946: c->remote_window = rwindow;
1947: c->remote_maxpacket = rmaxpack;
1.69 markus 1948: if (c->type != SSH_CHANNEL_CONNECTING) {
1949: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1950: packet_put_int(c->remote_id);
1951: packet_put_int(c->self);
1952: packet_put_int(c->local_window);
1953: packet_put_int(c->local_maxpacket);
1954: packet_send();
1955: }
1.22 markus 1956: } else {
1957: debug("failure %s", ctype);
1958: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1959: packet_put_int(rchan);
1960: packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1.66 markus 1961: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.69 markus 1962: packet_put_cstring("open failed");
1.66 markus 1963: packet_put_cstring("");
1964: }
1.22 markus 1965: packet_send();
1966: }
1967: xfree(ctype);
1968: }
1.77 itojun 1969: static void
1.94 markus 1970: client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1.48 markus 1971: {
1972: Channel *c = NULL;
1.123 djm 1973: int exitval, id, reply, success = 0;
1.48 markus 1974: char *rtype;
1975:
1976: id = packet_get_int();
1977: rtype = packet_get_string(NULL);
1978: reply = packet_get_char();
1979:
1980: debug("client_input_channel_req: channel %d rtype %s reply %d",
1981: id, rtype, reply);
1982:
1.128 djm 1983: if (id == -1) {
1984: error("client_input_channel_req: request for channel -1");
1985: } else if ((c = channel_lookup(id)) == NULL) {
1.197 djm 1986: error("client_input_channel_req: channel %d: "
1987: "unknown channel", id);
1.193 markus 1988: } else if (strcmp(rtype, "eow@openssh.com") == 0) {
1989: packet_check_eom();
1990: chan_rcvd_eow(c);
1.48 markus 1991: } else if (strcmp(rtype, "exit-status") == 0) {
1.123 djm 1992: exitval = packet_get_int();
1.217 djm 1993: if (c->ctl_chan != -1) {
1994: mux_exit_message(c, exitval);
1.215 djm 1995: success = 1;
1996: } else if (id == session_ident) {
1997: /* Record exit value of local session */
1.123 djm 1998: success = 1;
1999: exit_status = exitval;
1.215 djm 2000: } else {
1.218 djm 2001: /* Probably for a mux channel that has already closed */
2002: debug("%s: no sink for exit-status on channel %d",
2003: __func__, id);
1.123 djm 2004: }
1.93 markus 2005: packet_check_eom();
1.48 markus 2006: }
1.226 djm 2007: if (reply && c != NULL) {
1.48 markus 2008: packet_start(success ?
2009: SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1.205 markus 2010: packet_put_int(c->remote_id);
1.48 markus 2011: packet_send();
2012: }
2013: xfree(rtype);
2014: }
1.95 markus 2015: static void
2016: client_input_global_request(int type, u_int32_t seq, void *ctxt)
2017: {
2018: char *rtype;
2019: int want_reply;
2020: int success = 0;
2021:
2022: rtype = packet_get_string(NULL);
2023: want_reply = packet_get_char();
1.117 markus 2024: debug("client_input_global_request: rtype %s want_reply %d",
2025: rtype, want_reply);
1.95 markus 2026: if (want_reply) {
2027: packet_start(success ?
2028: SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
2029: packet_send();
2030: packet_write_wait();
2031: }
2032: xfree(rtype);
2033: }
1.22 markus 2034:
1.123 djm 2035: void
1.129 deraadt 2036: client_session2_setup(int id, int want_tty, int want_subsystem,
1.190 djm 2037: const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
1.123 djm 2038: {
2039: int len;
1.132 djm 2040: Channel *c = NULL;
1.123 djm 2041:
2042: debug2("%s: id %d", __func__, id);
2043:
1.132 djm 2044: if ((c = channel_lookup(id)) == NULL)
2045: fatal("client_session2_setup: channel %d: unknown channel", id);
1.224 djm 2046:
2047: packet_set_interactive(want_tty,
2048: options.ip_qos_interactive, options.ip_qos_bulk);
1.132 djm 2049:
1.123 djm 2050: if (want_tty) {
2051: struct winsize ws;
2052:
2053: /* Store window size in the packet. */
2054: if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
2055: memset(&ws, 0, sizeof(ws));
2056:
1.190 djm 2057: channel_request_start(id, "pty-req", 1);
1.234 djm 2058: client_expect_confirm(id, "PTY allocation", CONFIRM_TTY);
1.123 djm 2059: packet_put_cstring(term != NULL ? term : "");
1.158 deraadt 2060: packet_put_int((u_int)ws.ws_col);
2061: packet_put_int((u_int)ws.ws_row);
2062: packet_put_int((u_int)ws.ws_xpixel);
2063: packet_put_int((u_int)ws.ws_ypixel);
1.194 djm 2064: if (tiop == NULL)
2065: tiop = get_saved_tio();
2066: tty_make_modes(-1, tiop);
1.123 djm 2067: packet_send();
2068: /* XXX wait for reply */
1.132 djm 2069: c->client_tty = 1;
1.123 djm 2070: }
2071:
2072: /* Transfer any environment variables from client to server */
1.126 djm 2073: if (options.num_send_env != 0 && env != NULL) {
1.123 djm 2074: int i, j, matched;
2075: char *name, *val;
2076:
2077: debug("Sending environment.");
1.126 djm 2078: for (i = 0; env[i] != NULL; i++) {
1.123 djm 2079: /* Split */
1.126 djm 2080: name = xstrdup(env[i]);
1.123 djm 2081: if ((val = strchr(name, '=')) == NULL) {
1.144 stevesk 2082: xfree(name);
1.123 djm 2083: continue;
2084: }
2085: *val++ = '\0';
2086:
2087: matched = 0;
2088: for (j = 0; j < options.num_send_env; j++) {
2089: if (match_pattern(name, options.send_env[j])) {
2090: matched = 1;
2091: break;
2092: }
2093: }
2094: if (!matched) {
2095: debug3("Ignored env %s", name);
1.144 stevesk 2096: xfree(name);
1.123 djm 2097: continue;
2098: }
2099:
2100: debug("Sending env %s = %s", name, val);
2101: channel_request_start(id, "env", 0);
2102: packet_put_cstring(name);
2103: packet_put_cstring(val);
2104: packet_send();
1.144 stevesk 2105: xfree(name);
1.123 djm 2106: }
2107: }
2108:
2109: len = buffer_len(cmd);
2110: if (len > 0) {
2111: if (len > 900)
2112: len = 900;
2113: if (want_subsystem) {
1.190 djm 2114: debug("Sending subsystem: %.*s",
2115: len, (u_char*)buffer_ptr(cmd));
2116: channel_request_start(id, "subsystem", 1);
1.234 djm 2117: client_expect_confirm(id, "subsystem", CONFIRM_CLOSE);
1.123 djm 2118: } else {
1.190 djm 2119: debug("Sending command: %.*s",
2120: len, (u_char*)buffer_ptr(cmd));
2121: channel_request_start(id, "exec", 1);
1.234 djm 2122: client_expect_confirm(id, "exec", CONFIRM_CLOSE);
1.123 djm 2123: }
2124: packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
2125: packet_send();
2126: } else {
1.190 djm 2127: channel_request_start(id, "shell", 1);
1.234 djm 2128: client_expect_confirm(id, "shell", CONFIRM_CLOSE);
1.123 djm 2129: packet_send();
2130: }
2131: }
2132:
1.77 itojun 2133: static void
1.49 itojun 2134: client_init_dispatch_20(void)
1.16 markus 2135: {
1.55 markus 2136: dispatch_init(&dispatch_protocol_error);
1.100 markus 2137:
1.16 markus 2138: dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
2139: dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
2140: dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
2141: dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1.22 markus 2142: dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1.16 markus 2143: dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2144: dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1.48 markus 2145: dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1.16 markus 2146: dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1.189 djm 2147: dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
2148: dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
1.95 markus 2149: dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1.55 markus 2150:
2151: /* rekeying */
2152: dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1.100 markus 2153:
2154: /* global request reply messages */
2155: dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
2156: dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1.16 markus 2157: }
1.197 djm 2158:
1.77 itojun 2159: static void
1.49 itojun 2160: client_init_dispatch_13(void)
1.15 markus 2161: {
2162: dispatch_init(NULL);
2163: dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
2164: dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
2165: dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
2166: dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2167: dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2168: dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2169: dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2170: dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2171: dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1.39 markus 2172:
2173: dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1.115 markus 2174: &client_input_agent_open : &deny_input_open);
1.39 markus 2175: dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2176: &x11_input_open : &deny_input_open);
1.15 markus 2177: }
1.197 djm 2178:
1.77 itojun 2179: static void
1.49 itojun 2180: client_init_dispatch_15(void)
1.15 markus 2181: {
2182: client_init_dispatch_13();
2183: dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2184: dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2185: }
1.197 djm 2186:
1.79 stevesk 2187: static void
1.49 itojun 2188: client_init_dispatch(void)
1.15 markus 2189: {
1.16 markus 2190: if (compat20)
2191: client_init_dispatch_20();
2192: else if (compat13)
1.15 markus 2193: client_init_dispatch_13();
2194: else
2195: client_init_dispatch_15();
1.232 djm 2196: }
2197:
2198: void
2199: client_stop_mux(void)
2200: {
2201: if (options.control_path != NULL && muxserver_sock != -1)
2202: unlink(options.control_path);
2203: /*
2204: * If we are in persist mode, signal that we should close when all
2205: * active channels are closed.
2206: */
1.235 djm 2207: if (options.control_persist) {
1.232 djm 2208: session_closed = 1;
1.235 djm 2209: setproctitle("[stopped mux]");
2210: }
1.113 markus 2211: }
2212:
2213: /* client specific fatal cleanup */
2214: void
1.114 markus 2215: cleanup_exit(int i)
1.113 markus 2216: {
1.233 djm 2217: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.113 markus 2218: leave_non_blocking();
1.192 djm 2219: if (options.control_path != NULL && muxserver_sock != -1)
1.123 djm 2220: unlink(options.control_path);
1.223 djm 2221: ssh_kill_proxy_command();
1.114 markus 2222: _exit(i);
1.1 deraadt 2223: }
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