Annotation of src/usr.bin/ssh/clientloop.c, Revision 1.406
1.406 ! djm 1: /* $OpenBSD: clientloop.c,v 1.405 2024/04/30 02:14:10 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>
1.189 djm 68: #include <sys/queue.h>
1.150 stevesk 69:
1.155 stevesk 70: #include <ctype.h>
1.168 stevesk 71: #include <errno.h>
1.151 stevesk 72: #include <paths.h>
1.374 djm 73: #include <poll.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>
1.328 deraadt 78: #include <stdarg.h>
1.150 stevesk 79: #include <termios.h>
1.175 deraadt 80: #include <pwd.h>
1.169 stevesk 81: #include <unistd.h>
1.266 deraadt 82: #include <limits.h>
1.1 deraadt 83:
1.175 deraadt 84: #include "xmalloc.h"
1.45 markus 85: #include "ssh.h"
86: #include "ssh2.h"
1.1 deraadt 87: #include "packet.h"
1.315 markus 88: #include "sshbuf.h"
1.15 markus 89: #include "compat.h"
1.74 markus 90: #include "channels.h"
1.15 markus 91: #include "dispatch.h"
1.317 markus 92: #include "sshkey.h"
1.175 deraadt 93: #include "cipher.h"
1.54 markus 94: #include "kex.h"
1.275 markus 95: #include "myproposal.h"
1.45 markus 96: #include "log.h"
1.261 millert 97: #include "misc.h"
1.45 markus 98: #include "readconf.h"
99: #include "clientloop.h"
1.147 djm 100: #include "sshconnect.h"
1.40 markus 101: #include "authfd.h"
1.45 markus 102: #include "atomicio.h"
1.118 deraadt 103: #include "sshpty.h"
1.123 djm 104: #include "match.h"
105: #include "msg.h"
1.262 djm 106: #include "ssherr.h"
1.267 djm 107: #include "hostfile.h"
1.319 djm 108:
1.375 djm 109: /* Permitted RSA signature algorithms for UpdateHostkeys proofs */
110: #define HOSTKEY_PROOF_RSA_ALGS "rsa-sha2-512,rsa-sha2-256"
111:
1.397 djm 112: /* Uncertainty (in percent) of keystroke timing intervals */
113: #define SSH_KEYSTROKE_TIMING_FUZZ 10
114:
1.39 markus 115: /* import options */
116: extern Options options;
1.1 deraadt 117:
1.123 djm 118: /* Control socket */
1.217 djm 119: extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */
1.123 djm 120:
1.13 markus 121: /*
122: * Name of the host we are connecting to. This is the name given on the
1.324 jmc 123: * command line, or the Hostname specified for the user-supplied name in a
1.13 markus 124: * configuration file.
125: */
1.1 deraadt 126: extern char *host;
127:
1.13 markus 128: /*
1.330 djm 129: * If this field is not NULL, the ForwardAgent socket is this path and different
130: * instead of SSH_AUTH_SOCK.
131: */
132: extern char *forward_agent_sock_path;
133:
134: /*
1.13 markus 135: * Flag to indicate that we have received a window change signal which has
136: * not yet been processed. This will cause a message indicating the new
137: * window size to be sent to the server a little later. This is volatile
138: * because this is updated in a signal handler.
139: */
1.88 markus 140: static volatile sig_atomic_t received_window_change_signal = 0;
141: static volatile sig_atomic_t received_signal = 0;
1.1 deraadt 142:
1.222 djm 143: /* Time when backgrounded control master using ControlPersist should exit */
144: static time_t control_persist_exit_time = 0;
145:
1.1 deraadt 146: /* Common data for the client loop code. */
1.217 djm 147: volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
1.11 markus 148: static int last_was_cr; /* Last character was a newline. */
1.197 djm 149: static int exit_status; /* Used to store the command exit status. */
1.11 markus 150: static int connection_in; /* Connection to server (input). */
151: static int connection_out; /* Connection to server (output). */
1.56 markus 152: static int need_rekeying; /* Set to non-zero if rekeying is requested. */
1.221 djm 153: static int session_closed; /* In SSH2: login session closed. */
1.388 dtucker 154: static time_t x11_refuse_time; /* If >0, refuse x11 opens after this time. */
1.345 dtucker 155: static time_t server_alive_time; /* Time to do server_alive_check */
1.384 djm 156: static int hostkeys_update_complete;
157: static int session_setup_complete;
1.1 deraadt 158:
1.321 djm 159: static void client_init_dispatch(struct ssh *ssh);
1.16 markus 160: int session_ident = -1;
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 */
1.303 djm 176: /* XXX move to struct ssh? */
1.196 djm 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:
1.315 markus 187: void ssh_process_session2_setup(int, int, int, struct sshbuf *);
1.377 djm 188: static void quit_message(const char *fmt, ...)
189: __attribute__((__format__ (printf, 1, 2)));
190:
191: static void
192: quit_message(const char *fmt, ...)
193: {
1.406 ! djm 194: char *msg, *fmt2;
1.377 djm 195: va_list args;
1.406 ! djm 196: xasprintf(&fmt2, "%s\r\n", fmt);
1.377 djm 197:
198: va_start(args, fmt);
1.406 ! djm 199: xvasprintf(&msg, fmt2, args);
1.377 djm 200: va_end(args);
201:
1.406 ! djm 202: (void)atomicio(vwrite, STDERR_FILENO, msg, strlen(msg));
1.402 dtucker 203: free(msg);
1.406 ! djm 204: free(fmt2);
! 205:
1.377 djm 206: quit_pending = 1;
207: }
1.123 djm 208:
1.13 markus 209: /*
210: * Signal handler for the window change signal (SIGWINCH). This just sets a
211: * flag indicating that the window has changed.
212: */
1.77 itojun 213: static void
1.11 markus 214: window_change_handler(int sig)
1.1 deraadt 215: {
1.11 markus 216: received_window_change_signal = 1;
1.1 deraadt 217: }
218:
1.13 markus 219: /*
220: * Signal handler for signals that cause the program to terminate. These
221: * signals must be trapped to restore terminal modes.
222: */
1.77 itojun 223: static void
1.11 markus 224: signal_handler(int sig)
1.1 deraadt 225: {
1.75 markus 226: received_signal = sig;
227: quit_pending = 1;
1.1 deraadt 228: }
229:
1.13 markus 230: /*
1.222 djm 231: * Sets control_persist_exit_time to the absolute time when the
232: * backgrounded control master should exit due to expiry of the
233: * ControlPersist timeout. Sets it to 0 if we are not a backgrounded
234: * control master process, or if there is no ControlPersist timeout.
235: */
236: static void
1.303 djm 237: set_control_persist_exit_time(struct ssh *ssh)
1.222 djm 238: {
239: if (muxserver_sock == -1 || !options.control_persist
1.232 djm 240: || options.control_persist_timeout == 0) {
1.222 djm 241: /* not using a ControlPersist timeout */
242: control_persist_exit_time = 0;
1.303 djm 243: } else if (channel_still_open(ssh)) {
1.222 djm 244: /* some client connections are still open */
245: if (control_persist_exit_time > 0)
1.354 djm 246: debug2_f("cancel scheduled exit");
1.222 djm 247: control_persist_exit_time = 0;
248: } else if (control_persist_exit_time <= 0) {
249: /* a client connection has recently closed */
1.251 dtucker 250: control_persist_exit_time = monotime() +
1.222 djm 251: (time_t)options.control_persist_timeout;
1.354 djm 252: debug2_f("schedule exit in %d seconds",
1.222 djm 253: options.control_persist_timeout);
254: }
255: /* else we are already counting down to the timeout */
256: }
257:
1.238 dtucker 258: #define SSH_X11_VALID_DISPLAY_CHARS ":/.-_"
259: static int
260: client_x11_display_valid(const char *display)
261: {
262: size_t i, dlen;
263:
1.279 djm 264: if (display == NULL)
265: return 0;
266:
1.238 dtucker 267: dlen = strlen(display);
268: for (i = 0; i < dlen; i++) {
1.256 deraadt 269: if (!isalnum((u_char)display[i]) &&
1.238 dtucker 270: strchr(SSH_X11_VALID_DISPLAY_CHARS, display[i]) == NULL) {
271: debug("Invalid character '%c' in DISPLAY", display[i]);
272: return 0;
273: }
274: }
275: return 1;
276: }
277:
1.274 djm 278: #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
279: #define X11_TIMEOUT_SLACK 60
1.279 djm 280: int
1.303 djm 281: client_x11_get_proto(struct ssh *ssh, const char *display,
282: const char *xauth_path, u_int trusted, u_int timeout,
283: char **_proto, char **_data)
1.138 djm 284: {
1.318 djm 285: char *cmd, line[512], xdisplay[512];
1.279 djm 286: char xauthfile[PATH_MAX], xauthdir[PATH_MAX];
1.138 djm 287: static char proto[512], data[512];
288: FILE *f;
1.288 tedu 289: int got_data = 0, generated = 0, do_unlink = 0, r;
1.138 djm 290: struct stat st;
1.274 djm 291: u_int now, x11_timeout_real;
1.138 djm 292:
293: *_proto = proto;
294: *_data = data;
1.279 djm 295: proto[0] = data[0] = xauthfile[0] = xauthdir[0] = '\0';
1.138 djm 296:
1.279 djm 297: if (!client_x11_display_valid(display)) {
1.283 millert 298: if (display != NULL)
299: logit("DISPLAY \"%s\" invalid; disabling X11 forwarding",
300: display);
1.279 djm 301: return -1;
302: }
303: if (xauth_path != NULL && stat(xauth_path, &st) == -1) {
1.138 djm 304: debug("No xauth program.");
1.279 djm 305: xauth_path = NULL;
306: }
307:
308: if (xauth_path != NULL) {
1.138 djm 309: /*
310: * Handle FamilyLocal case where $DISPLAY does
311: * not match an authorization entry. For this we
312: * just try "xauth list unix:displaynum.screennum".
313: * XXX: "localhost" match to determine FamilyLocal
314: * is not perfect.
315: */
316: if (strncmp(display, "localhost:", 10) == 0) {
1.279 djm 317: if ((r = snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
318: display + 10)) < 0 ||
319: (size_t)r >= sizeof(xdisplay)) {
1.354 djm 320: error_f("display name too long");
1.279 djm 321: return -1;
322: }
1.138 djm 323: display = xdisplay;
324: }
325: if (trusted == 0) {
1.274 djm 326: /*
1.279 djm 327: * Generate an untrusted X11 auth cookie.
328: *
1.274 djm 329: * The authentication cookie should briefly outlive
330: * ssh's willingness to forward X11 connections to
331: * avoid nasty fail-open behaviour in the X server.
332: */
1.279 djm 333: mktemp_proto(xauthdir, sizeof(xauthdir));
334: if (mkdtemp(xauthdir) == NULL) {
1.354 djm 335: error_f("mkdtemp: %s", strerror(errno));
1.279 djm 336: return -1;
337: }
338: do_unlink = 1;
339: if ((r = snprintf(xauthfile, sizeof(xauthfile),
340: "%s/xauthfile", xauthdir)) < 0 ||
341: (size_t)r >= sizeof(xauthfile)) {
1.354 djm 342: error_f("xauthfile path too long");
1.279 djm 343: rmdir(xauthdir);
344: return -1;
345: }
346:
1.318 djm 347: if (timeout == 0) {
348: /* auth doesn't time out */
349: xasprintf(&cmd, "%s -f %s generate %s %s "
350: "untrusted 2>%s",
351: xauth_path, xauthfile, display,
352: SSH_X11_PROTO, _PATH_DEVNULL);
353: } else {
354: /* Add some slack to requested expiry */
355: if (timeout < UINT_MAX - X11_TIMEOUT_SLACK)
356: x11_timeout_real = timeout +
357: X11_TIMEOUT_SLACK;
358: else {
359: /* Don't overflow on long timeouts */
360: x11_timeout_real = UINT_MAX;
361: }
362: xasprintf(&cmd, "%s -f %s generate %s %s "
363: "untrusted timeout %u 2>%s",
364: xauth_path, xauthfile, display,
365: SSH_X11_PROTO, x11_timeout_real,
366: _PATH_DEVNULL);
367: }
1.354 djm 368: debug2_f("xauth command: %s", cmd);
1.318 djm 369:
370: if (timeout != 0 && x11_refuse_time == 0) {
1.279 djm 371: now = monotime() + 1;
1.388 dtucker 372: if (SSH_TIME_T_MAX - timeout < now)
373: x11_refuse_time = SSH_TIME_T_MAX;
1.279 djm 374: else
375: x11_refuse_time = now + timeout;
1.303 djm 376: channel_set_x11_refuse_time(ssh,
377: x11_refuse_time);
1.138 djm 378: }
1.279 djm 379: if (system(cmd) == 0)
380: generated = 1;
1.318 djm 381: free(cmd);
1.138 djm 382: }
1.181 markus 383:
384: /*
385: * When in untrusted mode, we read the cookie only if it was
386: * successfully generated as an untrusted one in the step
387: * above.
388: */
389: if (trusted || generated) {
1.318 djm 390: xasprintf(&cmd,
1.181 markus 391: "%s %s%s list %s 2>" _PATH_DEVNULL,
392: xauth_path,
393: generated ? "-f " : "" ,
394: generated ? xauthfile : "",
395: display);
396: debug2("x11_get_proto: %s", cmd);
397: f = popen(cmd, "r");
398: if (f && fgets(line, sizeof(line), f) &&
399: sscanf(line, "%*s %511s %511s", proto, data) == 2)
400: got_data = 1;
401: if (f)
402: pclose(f);
1.318 djm 403: free(cmd);
1.279 djm 404: }
1.138 djm 405: }
406:
407: if (do_unlink) {
408: unlink(xauthfile);
409: rmdir(xauthdir);
410: }
411:
1.279 djm 412: /* Don't fall back to fake X11 data for untrusted forwarding */
413: if (!trusted && !got_data) {
414: error("Warning: untrusted X11 forwarding setup failed: "
415: "xauth key data not generated");
416: return -1;
417: }
418:
1.138 djm 419: /*
420: * If we didn't get authentication data, just make up some
421: * data. The forwarding code will check the validity of the
422: * response anyway, and substitute this data. The X11
423: * server, however, will ignore this fake data and use
424: * whatever authentication mechanisms it was using otherwise
425: * for the local connection.
426: */
427: if (!got_data) {
1.288 tedu 428: u_int8_t rnd[16];
429: u_int i;
1.138 djm 430:
431: logit("Warning: No xauth data; "
432: "using fake authentication data for X11 forwarding.");
433: strlcpy(proto, SSH_X11_PROTO, sizeof proto);
1.288 tedu 434: arc4random_buf(rnd, sizeof(rnd));
435: for (i = 0; i < sizeof(rnd); i++) {
1.138 djm 436: snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
1.288 tedu 437: rnd[i]);
1.138 djm 438: }
439: }
1.279 djm 440:
441: return 0;
1.1 deraadt 442: }
443:
1.13 markus 444: /*
445: * Checks if the client window has changed, and sends a packet about it to
446: * the server if so. The actual change is detected elsewhere (by a software
447: * interrupt on Unix); this just checks the flag and sends a message if
448: * appropriate.
449: */
1.1 deraadt 450:
1.77 itojun 451: static void
1.303 djm 452: client_check_window_change(struct ssh *ssh)
1.1 deraadt 453: {
1.292 djm 454: if (!received_window_change_signal)
1.16 markus 455: return;
456: received_window_change_signal = 0;
1.354 djm 457: debug2_f("changed");
1.303 djm 458: channel_send_window_changes(ssh);
1.1 deraadt 459: }
460:
1.264 markus 461: static int
1.297 markus 462: client_global_request_reply(int type, u_int32_t seq, struct ssh *ssh)
1.117 markus 463: {
1.196 djm 464: struct global_confirm *gc;
465:
466: if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
1.264 markus 467: return 0;
1.196 djm 468: if (gc->cb != NULL)
1.303 djm 469: gc->cb(ssh, type, seq, gc->ctx);
1.196 djm 470: if (--gc->ref_count <= 0) {
471: TAILQ_REMOVE(&global_confirms, gc, entry);
1.342 jsg 472: freezero(gc, sizeof(*gc));
1.196 djm 473: }
474:
1.320 djm 475: ssh_packet_set_alive_timeouts(ssh, 0);
1.264 markus 476: return 0;
1.117 markus 477: }
478:
479: static void
1.345 dtucker 480: schedule_server_alive_check(void)
481: {
482: if (options.server_alive_interval > 0)
483: server_alive_time = monotime() + options.server_alive_interval;
484: }
485:
486: static void
1.320 djm 487: server_alive_check(struct ssh *ssh)
1.117 markus 488: {
1.320 djm 489: int r;
490:
491: if (ssh_packet_inc_alive_timeouts(ssh) > options.server_alive_count_max) {
1.228 djm 492: logit("Timeout, server %s not responding.", host);
1.176 markus 493: cleanup_exit(255);
494: }
1.320 djm 495: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
496: (r = sshpkt_put_cstring(ssh, "keepalive@openssh.com")) != 0 ||
497: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* boolean: want reply */
498: (r = sshpkt_send(ssh)) != 0)
1.354 djm 499: fatal_fr(r, "send packet");
1.196 djm 500: /* Insert an empty placeholder to maintain ordering */
501: client_register_global_confirm(NULL, NULL);
1.345 dtucker 502: schedule_server_alive_check();
1.117 markus 503: }
504:
1.393 djm 505: /* Try to send a dummy keystroke */
506: static int
507: send_chaff(struct ssh *ssh)
508: {
509: int r;
510:
1.403 djm 511: if (ssh->kex == NULL || (ssh->kex->flags & KEX_HAS_PING) == 0)
1.393 djm 512: return 0;
513: /* XXX probabilistically send chaff? */
514: /*
515: * a SSH2_MSG_CHANNEL_DATA payload is 9 bytes:
516: * 4 bytes channel ID + 4 bytes string length + 1 byte string data
517: * simulate that here.
518: */
519: if ((r = sshpkt_start(ssh, SSH2_MSG_PING)) != 0 ||
520: (r = sshpkt_put_cstring(ssh, "PING!")) != 0 ||
521: (r = sshpkt_send(ssh)) != 0)
522: fatal_fr(r, "send packet");
523: return 1;
524: }
525:
1.397 djm 526: /* Sets the next interval to send a keystroke or chaff packet */
527: static void
528: set_next_interval(const struct timespec *now, struct timespec *next_interval,
529: u_int interval_ms, int starting)
530: {
531: struct timespec tmp;
532: long long interval_ns, fuzz_ns;
533: static long long rate_fuzz;
534:
535: interval_ns = interval_ms * (1000LL * 1000);
536: fuzz_ns = (interval_ns * SSH_KEYSTROKE_TIMING_FUZZ) / 100;
537: /* Center fuzz around requested interval */
538: if (fuzz_ns > INT_MAX)
539: fuzz_ns = INT_MAX;
540: if (fuzz_ns > interval_ns) {
541: /* Shouldn't happen */
542: fatal_f("internal error: fuzz %u%% %lldns > interval %lldns",
543: SSH_KEYSTROKE_TIMING_FUZZ, fuzz_ns, interval_ns);
544: }
545: /*
546: * Randomise the keystroke/chaff intervals in two ways:
547: * 1. Each interval has some random jitter applied to make the
548: * interval-to-interval time unpredictable.
549: * 2. The overall interval rate is also randomly perturbed for each
1.398 djm 550: * chaffing session to make the average rate unpredictable.
1.397 djm 551: */
552: if (starting)
553: rate_fuzz = arc4random_uniform(fuzz_ns);
554: interval_ns -= fuzz_ns;
555: interval_ns += arc4random_uniform(fuzz_ns) + rate_fuzz;
556:
557: tmp.tv_sec = interval_ns / (1000 * 1000 * 1000);
558: tmp.tv_nsec = interval_ns % (1000 * 1000 * 1000);
559:
560: timespecadd(now, &tmp, next_interval);
561: }
562:
1.393 djm 563: /*
564: * Performs keystroke timing obfuscation. Returns non-zero if the
565: * output fd should be polled.
566: */
567: static int
1.396 djm 568: obfuscate_keystroke_timing(struct ssh *ssh, struct timespec *timeout,
569: int channel_did_enqueue)
1.393 djm 570: {
571: static int active;
572: static struct timespec next_interval, chaff_until;
573: struct timespec now, tmp;
574: int just_started = 0, had_keystroke = 0;
575: static unsigned long long nchaff;
576: char *stop_reason = NULL;
577: long long n;
578:
579: monotime_ts(&now);
580:
581: if (options.obscure_keystroke_timing_interval <= 0)
582: return 1; /* disabled in config */
583:
1.401 djm 584: if (!channel_tty_open(ssh) || quit_pending) {
1.393 djm 585: /* Stop if no channels left of we're waiting for one to close */
586: stop_reason = "no active channels";
587: } else if (ssh_packet_is_rekeying(ssh)) {
588: /* Stop if we're rekeying */
589: stop_reason = "rekeying started";
590: } else if (!ssh_packet_interactive_data_to_write(ssh) &&
591: ssh_packet_have_data_to_write(ssh)) {
592: /* Stop if the output buffer has more than a few keystrokes */
593: stop_reason = "output buffer filling";
1.396 djm 594: } else if (active && channel_did_enqueue &&
595: ssh_packet_have_data_to_write(ssh)) {
1.393 djm 596: /* Still in active mode and have a keystroke queued. */
597: had_keystroke = 1;
598: } else if (active) {
599: if (timespeccmp(&now, &chaff_until, >=)) {
600: /* Stop if there have been no keystrokes for a while */
601: stop_reason = "chaff time expired";
602: } else if (timespeccmp(&now, &next_interval, >=)) {
603: /* Otherwise if we were due to send, then send chaff */
604: if (send_chaff(ssh))
605: nchaff++;
606: }
607: }
608:
609: if (stop_reason != NULL) {
1.395 djm 610: if (active) {
611: debug3_f("stopping: %s (%llu chaff packets sent)",
612: stop_reason, nchaff);
613: active = 0;
614: }
1.393 djm 615: return 1;
616: }
617:
618: /*
619: * If we're in interactive mode, and only have a small amount
620: * of outbound data, then we assume that the user is typing
621: * interactively. In this case, start quantising outbound packets to
622: * fixed time intervals to hide inter-keystroke timing.
623: */
1.396 djm 624: if (!active && ssh_packet_interactive_data_to_write(ssh) &&
625: channel_did_enqueue && ssh_packet_have_data_to_write(ssh)) {
1.397 djm 626: debug3_f("starting: interval ~%dms",
1.393 djm 627: options.obscure_keystroke_timing_interval);
628: just_started = had_keystroke = active = 1;
629: nchaff = 0;
1.397 djm 630: set_next_interval(&now, &next_interval,
631: options.obscure_keystroke_timing_interval, 1);
1.393 djm 632: }
633:
634: /* Don't hold off if obfuscation inactive */
635: if (!active)
636: return 1;
637:
638: if (had_keystroke) {
639: /*
640: * Arrange to send chaff packets for a random interval after
641: * the last keystroke was sent.
642: */
643: ms_to_timespec(&tmp, SSH_KEYSTROKE_CHAFF_MIN_MS +
644: arc4random_uniform(SSH_KEYSTROKE_CHAFF_RNG_MS));
645: timespecadd(&now, &tmp, &chaff_until);
646: }
647:
648: ptimeout_deadline_monotime_tsp(timeout, &next_interval);
649:
650: if (just_started)
651: return 1;
652:
653: /* Don't arm output fd for poll until the timing interval has elapsed */
654: if (timespeccmp(&now, &next_interval, <))
655: return 0;
656:
657: /* Calculate number of intervals missed since the last check */
1.394 djm 658: n = (now.tv_sec - next_interval.tv_sec) * 1000LL * 1000 * 1000;
1.393 djm 659: n += now.tv_nsec - next_interval.tv_nsec;
1.394 djm 660: n /= options.obscure_keystroke_timing_interval * 1000LL * 1000;
1.393 djm 661: n = (n < 0) ? 1 : n + 1;
662:
663: /* Advance to the next interval */
1.397 djm 664: set_next_interval(&now, &next_interval,
665: options.obscure_keystroke_timing_interval * n, 0);
1.393 djm 666: return 1;
667: }
668:
1.13 markus 669: /*
670: * Waits until the client can do something (some data becomes available on
671: * one of the file descriptors).
672: */
1.77 itojun 673: static void
1.374 djm 674: client_wait_until_can_do_something(struct ssh *ssh, struct pollfd **pfdp,
1.396 djm 675: u_int *npfd_allocp, u_int *npfd_activep, int channel_did_enqueue,
1.400 djm 676: sigset_t *sigsetp, int *conn_in_readyp, int *conn_out_readyp)
1.11 markus 677: {
1.386 djm 678: struct timespec timeout;
1.393 djm 679: int ret, oready;
1.374 djm 680: u_int p;
1.117 markus 681:
1.374 djm 682: *conn_in_readyp = *conn_out_readyp = 0;
1.11 markus 683:
1.374 djm 684: /* Prepare channel poll. First two pollfd entries are reserved */
1.386 djm 685: ptimeout_init(&timeout);
686: channel_prepare_poll(ssh, pfdp, npfd_allocp, npfd_activep, 2, &timeout);
1.374 djm 687: if (*npfd_activep < 2)
688: fatal_f("bad npfd %u", *npfd_activep); /* shouldn't happen */
689:
690: /* channel_prepare_poll could have closed the last channel */
1.303 djm 691: if (session_closed && !channel_still_open(ssh) &&
1.320 djm 692: !ssh_packet_have_data_to_write(ssh)) {
1.374 djm 693: /* clear events since we did not call poll() */
694: for (p = 0; p < *npfd_activep; p++)
695: (*pfdp)[p].revents = 0;
1.292 djm 696: return;
1.16 markus 697: }
1.11 markus 698:
1.396 djm 699: oready = obfuscate_keystroke_timing(ssh, &timeout, channel_did_enqueue);
1.393 djm 700:
1.374 djm 701: /* Monitor server connection on reserved pollfd entries */
702: (*pfdp)[0].fd = connection_in;
703: (*pfdp)[0].events = POLLIN;
704: (*pfdp)[1].fd = connection_out;
1.393 djm 705: (*pfdp)[1].events = (oready && ssh_packet_have_data_to_write(ssh)) ?
706: POLLOUT : 0;
1.11 markus 707:
1.13 markus 708: /*
709: * Wait for something to happen. This will suspend the process until
1.374 djm 710: * some polled descriptor can be read, written, or has some other
1.222 djm 711: * event pending, or a timeout expires.
1.13 markus 712: */
1.386 djm 713: set_control_persist_exit_time(ssh);
714: if (control_persist_exit_time > 0)
715: ptimeout_deadline_monotime(&timeout, control_persist_exit_time);
1.345 dtucker 716: if (options.server_alive_interval > 0)
1.386 djm 717: ptimeout_deadline_monotime(&timeout, server_alive_time);
1.396 djm 718: if (options.rekey_interval > 0 && !ssh_packet_is_rekeying(ssh)) {
1.386 djm 719: ptimeout_deadline_sec(&timeout,
1.320 djm 720: ssh_packet_get_rekey_timeout(ssh));
1.386 djm 721: }
1.374 djm 722:
1.400 djm 723: ret = ppoll(*pfdp, *npfd_activep, ptimeout_get_tsp(&timeout), sigsetp);
1.222 djm 724:
1.326 deraadt 725: if (ret == -1) {
1.51 markus 726: /*
1.374 djm 727: * We have to clear the events because we return.
1.51 markus 728: * We have to return, because the mainloop checks for the flags
729: * set by the signal handlers.
730: */
1.374 djm 731: for (p = 0; p < *npfd_activep; p++)
732: (*pfdp)[p].revents = 0;
1.11 markus 733: if (errno == EINTR)
734: return;
735: /* Note: we might still have data in the buffers. */
1.377 djm 736: quit_message("poll: %s", strerror(errno));
1.374 djm 737: return;
738: }
739:
740: *conn_in_readyp = (*pfdp)[0].revents != 0;
741: *conn_out_readyp = (*pfdp)[1].revents != 0;
742:
743: if (options.server_alive_interval > 0 && !*conn_in_readyp &&
744: monotime() >= server_alive_time) {
1.249 dtucker 745: /*
1.374 djm 746: * ServerAlive check is needed. We can't rely on the poll
1.345 dtucker 747: * timing out since traffic on the client side such as port
748: * forwards can keep waking it up.
1.249 dtucker 749: */
1.345 dtucker 750: server_alive_check(ssh);
1.374 djm 751: }
1.11 markus 752: }
753:
1.77 itojun 754: static void
1.315 markus 755: client_suspend_self(struct sshbuf *bin, struct sshbuf *bout, struct sshbuf *berr)
1.1 deraadt 756: {
1.11 markus 757: /* Flush stdout and stderr buffers. */
1.315 markus 758: if (sshbuf_len(bout) > 0)
759: atomicio(vwrite, fileno(stdout), sshbuf_mutable_ptr(bout),
760: sshbuf_len(bout));
761: if (sshbuf_len(berr) > 0)
762: atomicio(vwrite, fileno(stderr), sshbuf_mutable_ptr(berr),
763: sshbuf_len(berr));
1.11 markus 764:
1.233 djm 765: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.11 markus 766:
1.305 djm 767: sshbuf_reset(bin);
768: sshbuf_reset(bout);
769: sshbuf_reset(berr);
1.11 markus 770:
771: /* Send the suspend signal to the program itself. */
772: kill(getpid(), SIGTSTP);
773:
1.132 djm 774: /* Reset window sizes in case they have changed */
775: received_window_change_signal = 1;
1.11 markus 776:
1.233 djm 777: enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.11 markus 778: }
779:
1.77 itojun 780: static void
1.374 djm 781: client_process_net_input(struct ssh *ssh)
1.11 markus 782: {
1.378 djm 783: int r;
1.11 markus 784:
1.13 markus 785: /*
786: * Read input from the server, and add any such data to the buffer of
787: * the packet subsystem.
788: */
1.374 djm 789: schedule_server_alive_check();
1.378 djm 790: if ((r = ssh_packet_process_read(ssh, connection_in)) == 0)
791: return; /* success */
792: if (r == SSH_ERR_SYSTEM_ERROR) {
793: if (errno == EAGAIN || errno == EINTR)
794: return;
795: if (errno == EPIPE) {
796: quit_message("Connection to %s closed by remote host.",
797: host);
798: return;
799: }
1.11 markus 800: }
1.378 djm 801: quit_message("Read from remote host %s: %s", host, ssh_err(r));
1.17 markus 802: }
1.16 markus 803:
1.97 jakob 804: static void
1.303 djm 805: client_status_confirm(struct ssh *ssh, int type, Channel *c, void *ctx)
1.123 djm 806: {
1.190 djm 807: struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
808: char errmsg[256];
1.315 markus 809: int r, tochan;
1.190 djm 810:
1.234 djm 811: /*
812: * If a TTY was explicitly requested, then a failure to allocate
813: * one is fatal.
814: */
815: if (cr->action == CONFIRM_TTY &&
816: (options.request_tty == REQUEST_TTY_FORCE ||
817: options.request_tty == REQUEST_TTY_YES))
818: cr->action = CONFIRM_CLOSE;
819:
1.312 djm 820: /* XXX suppress on mux _client_ quietmode */
1.190 djm 821: tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
1.217 djm 822: c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
1.190 djm 823:
824: if (type == SSH2_MSG_CHANNEL_SUCCESS) {
825: debug2("%s request accepted on channel %d",
826: cr->request_type, c->self);
827: } else if (type == SSH2_MSG_CHANNEL_FAILURE) {
828: if (tochan) {
829: snprintf(errmsg, sizeof(errmsg),
830: "%s request failed\r\n", cr->request_type);
831: } else {
832: snprintf(errmsg, sizeof(errmsg),
833: "%s request failed on channel %d",
834: cr->request_type, c->self);
835: }
836: /* If error occurred on primary session channel, then exit */
1.234 djm 837: if (cr->action == CONFIRM_CLOSE && c->self == session_ident)
1.190 djm 838: fatal("%s", errmsg);
1.234 djm 839: /*
840: * If error occurred on mux client, append to
841: * their stderr.
842: */
843: if (tochan) {
1.360 djm 844: debug3_f("channel %d: mux request: %s", c->self,
845: cr->request_type);
1.315 markus 846: if ((r = sshbuf_put(c->extended, errmsg,
847: strlen(errmsg))) != 0)
1.354 djm 848: fatal_fr(r, "sshbuf_put");
1.234 djm 849: } else
1.190 djm 850: error("%s", errmsg);
1.234 djm 851: if (cr->action == CONFIRM_TTY) {
852: /*
853: * If a TTY allocation error occurred, then arrange
854: * for the correct TTY to leave raw mode.
855: */
856: if (c->self == session_ident)
857: leave_raw_mode(0);
858: else
1.303 djm 859: mux_tty_alloc_failed(ssh, c);
1.234 djm 860: } else if (cr->action == CONFIRM_CLOSE) {
1.303 djm 861: chan_read_failed(ssh, c);
862: chan_write_failed(ssh, c);
1.190 djm 863: }
864: }
1.250 djm 865: free(cr);
1.190 djm 866: }
867:
868: static void
1.303 djm 869: client_abandon_status_confirm(struct ssh *ssh, Channel *c, void *ctx)
1.190 djm 870: {
1.250 djm 871: free(ctx);
1.190 djm 872: }
1.129 deraadt 873:
1.236 djm 874: void
1.303 djm 875: client_expect_confirm(struct ssh *ssh, int id, const char *request,
1.234 djm 876: enum confirm_action action)
1.190 djm 877: {
1.255 djm 878: struct channel_reply_ctx *cr = xcalloc(1, sizeof(*cr));
1.123 djm 879:
1.190 djm 880: cr->request_type = request;
1.234 djm 881: cr->action = action;
1.123 djm 882:
1.303 djm 883: channel_register_status_confirm(ssh, id, client_status_confirm,
1.190 djm 884: client_abandon_status_confirm, cr);
1.196 djm 885: }
886:
887: void
888: client_register_global_confirm(global_confirm_cb *cb, void *ctx)
889: {
1.201 djm 890: struct global_confirm *gc, *last_gc;
1.196 djm 891:
892: /* Coalesce identical callbacks */
1.201 djm 893: last_gc = TAILQ_LAST(&global_confirms, global_confirms);
894: if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
895: if (++last_gc->ref_count >= INT_MAX)
1.354 djm 896: fatal_f("last_gc->ref_count = %d",
897: last_gc->ref_count);
1.196 djm 898: return;
899: }
900:
1.255 djm 901: gc = xcalloc(1, sizeof(*gc));
1.196 djm 902: gc->cb = cb;
903: gc->ctx = ctx;
904: gc->ref_count = 1;
905: TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
1.123 djm 906: }
907:
1.384 djm 908: /*
909: * Returns non-zero if the client is able to handle a hostkeys-00@openssh.com
910: * hostkey update request.
911: */
912: static int
913: can_update_hostkeys(void)
914: {
915: if (hostkeys_update_complete)
916: return 0;
917: if (options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK &&
918: options.batch_mode)
919: return 0; /* won't ask in batchmode, so don't even try */
920: if (!options.update_hostkeys || options.num_user_hostfiles <= 0)
921: return 0;
922: return 1;
923: }
924:
1.385 dtucker 925: static void
926: client_repledge(void)
1.384 djm 927: {
928: debug3_f("enter");
929:
930: /* Might be able to tighten pledge now that session is established */
931: if (options.control_master || options.control_path != NULL ||
932: options.forward_x11 || options.fork_after_authentication ||
933: can_update_hostkeys() ||
934: (session_ident != -1 && !session_setup_complete)) {
935: /* Can't tighten */
936: return;
937: }
938: /*
939: * LocalCommand and UpdateHostkeys have finished, so can get rid of
940: * filesystem.
941: *
942: * XXX protocol allows a server can to change hostkeys during the
943: * connection at rekey time that could trigger a hostkeys update
944: * but AFAIK no implementations support this. Could improve by
945: * forcing known_hosts to be read-only or via unveil(2).
946: */
947: if (options.num_local_forwards != 0 ||
948: options.num_remote_forwards != 0 ||
949: options.num_permitted_remote_opens != 0 ||
950: options.enable_escape_commandline != 0) {
951: /* rfwd needs inet */
952: debug("pledge: network");
953: if (pledge("stdio unix inet dns proc tty", NULL) == -1)
954: fatal_f("pledge(): %s", strerror(errno));
955: } else if (options.forward_agent != 0) {
956: /* agent forwarding needs to open $SSH_AUTH_SOCK at will */
957: debug("pledge: agent");
958: if (pledge("stdio unix proc tty", NULL) == -1)
959: fatal_f("pledge(): %s", strerror(errno));
960: } else {
961: debug("pledge: fork");
962: if (pledge("stdio proc tty", NULL) == -1)
963: fatal_f("pledge(): %s", strerror(errno));
964: }
965: /* XXX further things to do:
966: *
967: * - might be able to get rid of proc if we kill ~^Z
968: * - ssh -N (no session)
969: * - stdio forwarding
970: * - sessions without tty
971: */
972: }
973:
1.123 djm 974: static void
1.303 djm 975: process_cmdline(struct ssh *ssh)
1.97 jakob 976: {
977: void (*handler)(int);
1.261 millert 978: char *s, *cmd;
979: int ok, delete = 0, local = 0, remote = 0, dynamic = 0;
980: struct Forward fwd;
1.97 jakob 981:
1.257 tedu 982: memset(&fwd, 0, sizeof(fwd));
1.183 djm 983:
1.233 djm 984: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.332 dtucker 985: handler = ssh_signal(SIGINT, SIG_IGN);
1.99 markus 986: cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
1.97 jakob 987: if (s == NULL)
988: goto out;
1.256 deraadt 989: while (isspace((u_char)*s))
1.97 jakob 990: s++;
1.121 djm 991: if (*s == '-')
992: s++; /* Skip cmdline '-', if any */
1.120 dtucker 993: if (*s == '\0')
1.97 jakob 994: goto out;
1.121 djm 995:
1.122 djm 996: if (*s == 'h' || *s == 'H' || *s == '?') {
1.121 djm 997: logit("Commands:");
1.164 djm 998: logit(" -L[bind_address:]port:host:hostport "
999: "Request local forward");
1000: logit(" -R[bind_address:]port:host:hostport "
1001: "Request remote forward");
1.204 stevesk 1002: logit(" -D[bind_address:]port "
1003: "Request dynamic forward");
1.237 markus 1004: logit(" -KL[bind_address:]port "
1005: "Cancel local forward");
1.165 stevesk 1006: logit(" -KR[bind_address:]port "
1.164 djm 1007: "Cancel remote forward");
1.237 markus 1008: logit(" -KD[bind_address:]port "
1009: "Cancel dynamic forward");
1.146 reyk 1010: if (!options.permit_local_command)
1011: goto out;
1.164 djm 1012: logit(" !args "
1013: "Execute local command");
1.146 reyk 1014: goto out;
1015: }
1016:
1017: if (*s == '!' && options.permit_local_command) {
1018: s++;
1019: ssh_local_cmd(s);
1.121 djm 1020: goto out;
1021: }
1022:
1023: if (*s == 'K') {
1024: delete = 1;
1025: s++;
1026: }
1.204 stevesk 1027: if (*s == 'L')
1028: local = 1;
1029: else if (*s == 'R')
1030: remote = 1;
1031: else if (*s == 'D')
1032: dynamic = 1;
1033: else {
1.109 itojun 1034: logit("Invalid command.");
1.97 jakob 1035: goto out;
1036: }
1.204 stevesk 1037:
1.256 deraadt 1038: while (isspace((u_char)*++s))
1.179 tedu 1039: ;
1.97 jakob 1040:
1.217 djm 1041: /* XXX update list of forwards in options */
1.121 djm 1042: if (delete) {
1.261 millert 1043: /* We pass 1 for dynamicfwd to restrict to 1 or 2 fields. */
1044: if (!parse_forward(&fwd, s, 1, 0)) {
1045: logit("Bad forwarding close specification.");
1.121 djm 1046: goto out;
1047: }
1.237 markus 1048: if (remote)
1.303 djm 1049: ok = channel_request_rforward_cancel(ssh, &fwd) == 0;
1.237 markus 1050: else if (dynamic)
1.303 djm 1051: ok = channel_cancel_lport_listener(ssh, &fwd,
1.261 millert 1052: 0, &options.fwd_opts) > 0;
1.237 markus 1053: else
1.303 djm 1054: ok = channel_cancel_lport_listener(ssh, &fwd,
1.261 millert 1055: CHANNEL_CANCEL_PORT_STATIC,
1056: &options.fwd_opts) > 0;
1.237 markus 1057: if (!ok) {
1.290 dtucker 1058: logit("Unknown port forwarding.");
1.237 markus 1059: goto out;
1060: }
1061: logit("Canceled forwarding.");
1.121 djm 1062: } else {
1.382 dtucker 1063: /* -R specs can be both dynamic or not, so check both. */
1064: if (remote) {
1065: if (!parse_forward(&fwd, s, 0, remote) &&
1066: !parse_forward(&fwd, s, 1, remote)) {
1067: logit("Bad remote forwarding specification.");
1068: goto out;
1069: }
1070: } else if (!parse_forward(&fwd, s, dynamic, remote)) {
1071: logit("Bad local forwarding specification.");
1.121 djm 1072: goto out;
1073: }
1.204 stevesk 1074: if (local || dynamic) {
1.303 djm 1075: if (!channel_setup_local_fwd_listener(ssh, &fwd,
1.261 millert 1076: &options.fwd_opts)) {
1.121 djm 1077: logit("Port forwarding failed.");
1078: goto out;
1079: }
1.135 djm 1080: } else {
1.303 djm 1081: if (channel_request_remote_forwarding(ssh, &fwd) < 0) {
1.167 markus 1082: logit("Port forwarding failed.");
1083: goto out;
1084: }
1.135 djm 1085: }
1.121 djm 1086: logit("Forwarding port.");
1087: }
1088:
1.97 jakob 1089: out:
1.332 dtucker 1090: ssh_signal(SIGINT, handler);
1.233 djm 1091: enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.250 djm 1092: free(cmd);
1093: free(fwd.listen_host);
1.261 millert 1094: free(fwd.listen_path);
1.250 djm 1095: free(fwd.connect_host);
1.261 millert 1096: free(fwd.connect_path);
1.97 jakob 1097: }
1098:
1.244 dtucker 1099: /* reasons to suppress output of an escape command in help output */
1100: #define SUPPRESS_NEVER 0 /* never suppress, always show */
1.292 djm 1101: #define SUPPRESS_MUXCLIENT 1 /* don't show in mux client sessions */
1102: #define SUPPRESS_MUXMASTER 2 /* don't show in mux master sessions */
1103: #define SUPPRESS_SYSLOG 4 /* don't show when logging to syslog */
1.383 djm 1104: #define SUPPRESS_NOCMDLINE 8 /* don't show when cmdline disabled*/
1.244 dtucker 1105: struct escape_help_text {
1106: const char *cmd;
1107: const char *text;
1108: unsigned int flags;
1109: };
1110: static struct escape_help_text esc_txt[] = {
1111: {".", "terminate session", SUPPRESS_MUXMASTER},
1112: {".", "terminate connection (and any multiplexed sessions)",
1113: SUPPRESS_MUXCLIENT},
1.292 djm 1114: {"B", "send a BREAK to the remote system", SUPPRESS_NEVER},
1.383 djm 1115: {"C", "open a command line", SUPPRESS_MUXCLIENT|SUPPRESS_NOCMDLINE},
1.292 djm 1116: {"R", "request rekey", SUPPRESS_NEVER},
1.246 dtucker 1117: {"V/v", "decrease/increase verbosity (LogLevel)", SUPPRESS_MUXCLIENT},
1.244 dtucker 1118: {"^Z", "suspend ssh", SUPPRESS_MUXCLIENT},
1119: {"#", "list forwarded connections", SUPPRESS_NEVER},
1120: {"&", "background ssh (when waiting for connections to terminate)",
1121: SUPPRESS_MUXCLIENT},
1122: {"?", "this message", SUPPRESS_NEVER},
1123: };
1124:
1125: static void
1.315 markus 1126: print_escape_help(struct sshbuf *b, int escape_char, int mux_client,
1127: int using_stderr)
1.244 dtucker 1128: {
1129: unsigned int i, suppress_flags;
1.315 markus 1130: int r;
1.244 dtucker 1131:
1.315 markus 1132: if ((r = sshbuf_putf(b,
1133: "%c?\r\nSupported escape sequences:\r\n", escape_char)) != 0)
1.354 djm 1134: fatal_fr(r, "sshbuf_putf");
1.244 dtucker 1135:
1.292 djm 1136: suppress_flags =
1.244 dtucker 1137: (mux_client ? SUPPRESS_MUXCLIENT : 0) |
1138: (mux_client ? 0 : SUPPRESS_MUXMASTER) |
1.383 djm 1139: (using_stderr ? 0 : SUPPRESS_SYSLOG) |
1140: (options.enable_escape_commandline == 0 ? SUPPRESS_NOCMDLINE : 0);
1.244 dtucker 1141:
1142: for (i = 0; i < sizeof(esc_txt)/sizeof(esc_txt[0]); i++) {
1143: if (esc_txt[i].flags & suppress_flags)
1144: continue;
1.315 markus 1145: if ((r = sshbuf_putf(b, " %c%-3s - %s\r\n",
1146: escape_char, esc_txt[i].cmd, esc_txt[i].text)) != 0)
1.354 djm 1147: fatal_fr(r, "sshbuf_putf");
1.244 dtucker 1148: }
1149:
1.315 markus 1150: if ((r = sshbuf_putf(b,
1.246 dtucker 1151: " %c%c - send the escape character by typing it twice\r\n"
1.244 dtucker 1152: "(Note that escapes are only recognized immediately after "
1.315 markus 1153: "newline.)\r\n", escape_char, escape_char)) != 0)
1.354 djm 1154: fatal_fr(r, "sshbuf_putf");
1.244 dtucker 1155: }
1156:
1.314 djm 1157: /*
1.296 naddy 1158: * Process the characters one by one.
1.195 djm 1159: */
1.77 itojun 1160: static int
1.303 djm 1161: process_escapes(struct ssh *ssh, Channel *c,
1.315 markus 1162: struct sshbuf *bin, struct sshbuf *bout, struct sshbuf *berr,
1.195 djm 1163: char *buf, int len)
1.31 markus 1164: {
1165: pid_t pid;
1.315 markus 1166: int r, bytes = 0;
1.42 markus 1167: u_int i;
1168: u_char ch;
1.31 markus 1169: char *s;
1.392 dtucker 1170: struct escape_filter_ctx *efc;
1.31 markus 1171:
1.392 dtucker 1172: if (c == NULL || c->filter_ctx == NULL || len <= 0)
1.294 djm 1173: return 0;
1.314 djm 1174:
1.392 dtucker 1175: efc = (struct escape_filter_ctx *)c->filter_ctx;
1.139 djm 1176:
1177: for (i = 0; i < (u_int)len; i++) {
1.31 markus 1178: /* Get one character at a time. */
1179: ch = buf[i];
1180:
1.294 djm 1181: if (efc->escape_pending) {
1.31 markus 1182: /* We have previously seen an escape character. */
1183: /* Clear the flag now. */
1.294 djm 1184: efc->escape_pending = 0;
1.31 markus 1185:
1186: /* Process the escaped character. */
1187: switch (ch) {
1188: case '.':
1189: /* Terminate the connection. */
1.315 markus 1190: if ((r = sshbuf_putf(berr, "%c.\r\n",
1191: efc->escape_char)) != 0)
1.354 djm 1192: fatal_fr(r, "sshbuf_putf");
1.217 djm 1193: if (c && c->ctl_chan != -1) {
1.387 djm 1194: channel_force_close(ssh, c, 1);
1.195 djm 1195: return 0;
1196: } else
1197: quit_pending = 1;
1.31 markus 1198: return -1;
1199:
1200: case 'Z' - 64:
1.195 djm 1201: /* XXX support this for mux clients */
1.217 djm 1202: if (c && c->ctl_chan != -1) {
1.245 dtucker 1203: char b[16];
1.195 djm 1204: noescape:
1.245 dtucker 1205: if (ch == 'Z' - 64)
1206: snprintf(b, sizeof b, "^Z");
1207: else
1208: snprintf(b, sizeof b, "%c", ch);
1.315 markus 1209: if ((r = sshbuf_putf(berr,
1.245 dtucker 1210: "%c%s escape not available to "
1.195 djm 1211: "multiplexed sessions\r\n",
1.315 markus 1212: efc->escape_char, b)) != 0)
1.354 djm 1213: fatal_fr(r, "sshbuf_putf");
1.195 djm 1214: continue;
1215: }
1.197 djm 1216: /* Suspend the program. Inform the user */
1.315 markus 1217: if ((r = sshbuf_putf(berr,
1218: "%c^Z [suspend ssh]\r\n",
1219: efc->escape_char)) != 0)
1.354 djm 1220: fatal_fr(r, "sshbuf_putf");
1.31 markus 1221:
1222: /* Restore terminal modes and suspend. */
1223: client_suspend_self(bin, bout, berr);
1224:
1225: /* We have been continued. */
1226: continue;
1227:
1.111 markus 1228: case 'B':
1.315 markus 1229: if ((r = sshbuf_putf(berr,
1230: "%cB\r\n", efc->escape_char)) != 0)
1.354 djm 1231: fatal_fr(r, "sshbuf_putf");
1.303 djm 1232: channel_request_start(ssh, c->self, "break", 0);
1.315 markus 1233: if ((r = sshpkt_put_u32(ssh, 1000)) != 0 ||
1234: (r = sshpkt_send(ssh)) != 0)
1.354 djm 1235: fatal_fr(r, "send packet");
1.111 markus 1236: continue;
1237:
1.54 markus 1238: case 'R':
1.357 djm 1239: if (ssh->compat & SSH_BUG_NOREKEY)
1.292 djm 1240: logit("Server does not "
1241: "support re-keying");
1242: else
1243: need_rekeying = 1;
1.54 markus 1244: continue;
1245:
1.242 dtucker 1246: case 'V':
1247: /* FALLTHROUGH */
1248: case 'v':
1249: if (c && c->ctl_chan != -1)
1250: goto noescape;
1251: if (!log_is_on_stderr()) {
1.315 markus 1252: if ((r = sshbuf_putf(berr,
1.242 dtucker 1253: "%c%c [Logging to syslog]\r\n",
1.315 markus 1254: efc->escape_char, ch)) != 0)
1.354 djm 1255: fatal_fr(r, "sshbuf_putf");
1.242 dtucker 1256: continue;
1257: }
1258: if (ch == 'V' && options.log_level >
1259: SYSLOG_LEVEL_QUIET)
1260: log_change_level(--options.log_level);
1261: if (ch == 'v' && options.log_level <
1262: SYSLOG_LEVEL_DEBUG3)
1263: log_change_level(++options.log_level);
1.315 markus 1264: if ((r = sshbuf_putf(berr,
1.294 djm 1265: "%c%c [LogLevel %s]\r\n",
1266: efc->escape_char, ch,
1.315 markus 1267: log_level_name(options.log_level))) != 0)
1.354 djm 1268: fatal_fr(r, "sshbuf_putf");
1.242 dtucker 1269: continue;
1270:
1.31 markus 1271: case '&':
1.392 dtucker 1272: if (c->ctl_chan != -1)
1.195 djm 1273: goto noescape;
1.31 markus 1274: /*
1.197 djm 1275: * Detach the program (continue to serve
1276: * connections, but put in background and no
1277: * more new connections).
1.31 markus 1278: */
1279: /* Restore tty modes. */
1.233 djm 1280: leave_raw_mode(
1281: options.request_tty == REQUEST_TTY_FORCE);
1.31 markus 1282:
1283: /* Stop listening for new connections. */
1.303 djm 1284: channel_stop_listening(ssh);
1.31 markus 1285:
1.354 djm 1286: if ((r = sshbuf_putf(berr, "%c& "
1287: "[backgrounded]\n", efc->escape_char)) != 0)
1288: fatal_fr(r, "sshbuf_putf");
1.31 markus 1289:
1290: /* Fork into background. */
1291: pid = fork();
1.326 deraadt 1292: if (pid == -1) {
1.31 markus 1293: error("fork: %.100s", strerror(errno));
1294: continue;
1295: }
1296: if (pid != 0) { /* This is the parent. */
1297: /* The parent just exits. */
1298: exit(0);
1299: }
1300: /* The child continues serving connections. */
1.292 djm 1301: /* fake EOF on stdin */
1.315 markus 1302: if ((r = sshbuf_put_u8(bin, 4)) != 0)
1.354 djm 1303: fatal_fr(r, "sshbuf_put_u8");
1.292 djm 1304: return -1;
1.31 markus 1305: case '?':
1.294 djm 1306: print_escape_help(berr, efc->escape_char,
1.244 dtucker 1307: (c && c->ctl_chan != -1),
1308: log_is_on_stderr());
1.31 markus 1309: continue;
1310:
1311: case '#':
1.315 markus 1312: if ((r = sshbuf_putf(berr, "%c#\r\n",
1313: efc->escape_char)) != 0)
1.354 djm 1314: fatal_fr(r, "sshbuf_putf");
1.303 djm 1315: s = channel_open_message(ssh);
1.315 markus 1316: if ((r = sshbuf_put(berr, s, strlen(s))) != 0)
1.354 djm 1317: fatal_fr(r, "sshbuf_put");
1.250 djm 1318: free(s);
1.97 jakob 1319: continue;
1320:
1321: case 'C':
1.217 djm 1322: if (c && c->ctl_chan != -1)
1.206 djm 1323: goto noescape;
1.383 djm 1324: if (options.enable_escape_commandline == 0) {
1325: if ((r = sshbuf_putf(berr,
1326: "commandline disabled\r\n")) != 0)
1327: fatal_fr(r, "sshbuf_putf");
1328: continue;
1329: }
1.303 djm 1330: process_cmdline(ssh);
1.31 markus 1331: continue;
1332:
1333: default:
1.294 djm 1334: if (ch != efc->escape_char) {
1.315 markus 1335: if ((r = sshbuf_put_u8(bin,
1336: efc->escape_char)) != 0)
1.354 djm 1337: fatal_fr(r, "sshbuf_put_u8");
1.31 markus 1338: bytes++;
1339: }
1340: /* Escaped characters fall through here */
1341: break;
1342: }
1343: } else {
1344: /*
1.197 djm 1345: * The previous character was not an escape char.
1346: * Check if this is an escape.
1.31 markus 1347: */
1.294 djm 1348: if (last_was_cr && ch == efc->escape_char) {
1.197 djm 1349: /*
1350: * It is. Set the flag and continue to
1351: * next character.
1352: */
1.294 djm 1353: efc->escape_pending = 1;
1.31 markus 1354: continue;
1355: }
1356: }
1357:
1358: /*
1359: * Normal character. Record whether it was a newline,
1360: * and append it to the buffer.
1361: */
1362: last_was_cr = (ch == '\r' || ch == '\n');
1.315 markus 1363: if ((r = sshbuf_put_u8(bin, ch)) != 0)
1.354 djm 1364: fatal_fr(r, "sshbuf_put_u8");
1.31 markus 1365: bytes++;
1366: }
1367: return bytes;
1368: }
1369:
1.13 markus 1370: /*
1.15 markus 1371: * Get packets from the connection input buffer, and process them as long as
1372: * there are packets available.
1373: *
1374: * Any unknown packets received during the actual
1375: * session cause the session to terminate. This is
1376: * intended to make debugging easier since no
1377: * confirmations are sent. Any compatible protocol
1378: * extensions must be negotiated during the
1379: * preparatory phase.
1380: */
1381:
1.77 itojun 1382: static void
1.321 djm 1383: client_process_buffered_input_packets(struct ssh *ssh)
1.15 markus 1384: {
1.321 djm 1385: ssh_dispatch_run_fatal(ssh, DISPATCH_NONBLOCK, &quit_pending);
1.15 markus 1386: }
1387:
1.31 markus 1388: /* scan buf[] for '~' before sending data to the peer */
1.30 markus 1389:
1.195 djm 1390: /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1391: void *
1392: client_new_escape_filter_ctx(int escape_char)
1393: {
1394: struct escape_filter_ctx *ret;
1395:
1.255 djm 1396: ret = xcalloc(1, sizeof(*ret));
1.195 djm 1397: ret->escape_pending = 0;
1398: ret->escape_char = escape_char;
1399: return (void *)ret;
1400: }
1401:
1.198 djm 1402: /* Free the escape filter context on channel free */
1403: void
1.303 djm 1404: client_filter_cleanup(struct ssh *ssh, int cid, void *ctx)
1.198 djm 1405: {
1.250 djm 1406: free(ctx);
1.198 djm 1407: }
1408:
1.195 djm 1409: int
1.303 djm 1410: client_simple_escape_filter(struct ssh *ssh, Channel *c, char *buf, int len)
1.30 markus 1411: {
1.190 djm 1412: if (c->extended_usage != CHAN_EXTENDED_WRITE)
1413: return 0;
1414:
1.303 djm 1415: return process_escapes(ssh, c, c->input, c->output, c->extended,
1.195 djm 1416: buf, len);
1.30 markus 1417: }
1418:
1.77 itojun 1419: static void
1.387 djm 1420: client_channel_closed(struct ssh *ssh, int id, int force, void *arg)
1.60 markus 1421: {
1.303 djm 1422: channel_cancel_cleanup(ssh, id);
1.60 markus 1423: session_closed = 1;
1.233 djm 1424: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.60 markus 1425: }
1426:
1.15 markus 1427: /*
1.13 markus 1428: * Implements the interactive session with the server. This is called after
1429: * the user has been authenticated, and a command has been started on the
1.72 stevesk 1430: * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1431: * used as an escape character for terminating or suspending the session.
1.13 markus 1432: */
1.20 markus 1433: int
1.303 djm 1434: client_loop(struct ssh *ssh, int have_pty, int escape_char_arg,
1435: int ssh2_chan_id)
1.1 deraadt 1436: {
1.374 djm 1437: struct pollfd *pfd = NULL;
1438: u_int npfd_alloc = 0, npfd_active = 0;
1.11 markus 1439: double start_time, total_time;
1.406 ! djm 1440: int channel_did_enqueue = 0, r;
1.200 markus 1441: u_int64_t ibytes, obytes;
1.374 djm 1442: int conn_in_ready, conn_out_ready;
1.400 djm 1443: sigset_t bsigset, osigset;
1.11 markus 1444:
1445: debug("Entering interactive session.");
1.384 djm 1446: session_ident = ssh2_chan_id;
1.277 semarie 1447:
1.278 semarie 1448: if (options.control_master &&
1.286 djm 1449: !option_clear_or_none(options.control_path)) {
1.278 semarie 1450: debug("pledge: id");
1.327 mestre 1451: if (pledge("stdio rpath wpath cpath unix inet dns recvfd sendfd proc exec id tty",
1.278 semarie 1452: NULL) == -1)
1.354 djm 1453: fatal_f("pledge(): %s", strerror(errno));
1.278 semarie 1454:
1455: } else if (options.forward_x11 || options.permit_local_command) {
1.277 semarie 1456: debug("pledge: exec");
1457: if (pledge("stdio rpath wpath cpath unix inet dns proc exec tty",
1458: NULL) == -1)
1.354 djm 1459: fatal_f("pledge(): %s", strerror(errno));
1.277 semarie 1460:
1461: } else if (options.update_hostkeys) {
1.373 jsg 1462: debug("pledge: filesystem");
1.277 semarie 1463: if (pledge("stdio rpath wpath cpath unix inet dns proc tty",
1464: NULL) == -1)
1.354 djm 1465: fatal_f("pledge(): %s", strerror(errno));
1.277 semarie 1466:
1.286 djm 1467: } else if (!option_clear_or_none(options.proxy_command) ||
1.369 djm 1468: options.fork_after_authentication) {
1.277 semarie 1469: debug("pledge: proc");
1470: if (pledge("stdio cpath unix inet dns proc tty", NULL) == -1)
1.354 djm 1471: fatal_f("pledge(): %s", strerror(errno));
1.277 semarie 1472:
1473: } else {
1474: debug("pledge: network");
1.300 mestre 1475: if (pledge("stdio unix inet dns proc tty", NULL) == -1)
1.354 djm 1476: fatal_f("pledge(): %s", strerror(errno));
1.277 semarie 1477: }
1.11 markus 1478:
1.384 djm 1479: /* might be able to tighten now */
1480: client_repledge();
1481:
1.307 dtucker 1482: start_time = monotime_double();
1.11 markus 1483:
1484: /* Initialize variables. */
1485: last_was_cr = 1;
1486: exit_status = -1;
1.320 djm 1487: connection_in = ssh_packet_get_connection_in(ssh);
1488: connection_out = ssh_packet_get_connection_out(ssh);
1.46 markus 1489:
1.11 markus 1490: quit_pending = 0;
1491:
1.321 djm 1492: client_init_dispatch(ssh);
1.15 markus 1493:
1.105 markus 1494: /*
1495: * Set signal handlers, (e.g. to restore non-blocking mode)
1496: * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1497: */
1.332 dtucker 1498: if (ssh_signal(SIGHUP, SIG_IGN) != SIG_IGN)
1499: ssh_signal(SIGHUP, signal_handler);
1500: if (ssh_signal(SIGINT, SIG_IGN) != SIG_IGN)
1501: ssh_signal(SIGINT, signal_handler);
1502: if (ssh_signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1503: ssh_signal(SIGQUIT, signal_handler);
1504: if (ssh_signal(SIGTERM, SIG_IGN) != SIG_IGN)
1505: ssh_signal(SIGTERM, signal_handler);
1506: ssh_signal(SIGWINCH, window_change_handler);
1.11 markus 1507:
1508: if (have_pty)
1.233 djm 1509: enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.11 markus 1510:
1.292 djm 1511: if (session_ident != -1) {
1512: if (escape_char_arg != SSH_ESCAPECHAR_NONE) {
1.303 djm 1513: channel_register_filter(ssh, session_ident,
1.292 djm 1514: client_simple_escape_filter, NULL,
1515: client_filter_cleanup,
1516: client_new_escape_filter_ctx(
1517: escape_char_arg));
1.232 djm 1518: }
1.303 djm 1519: channel_register_cleanup(ssh, session_ident,
1.292 djm 1520: client_channel_closed, 0);
1.48 markus 1521: }
1.345 dtucker 1522:
1523: schedule_server_alive_check();
1.30 markus 1524:
1.400 djm 1525: if (sigemptyset(&bsigset) == -1 ||
1526: sigaddset(&bsigset, SIGHUP) == -1 ||
1527: sigaddset(&bsigset, SIGINT) == -1 ||
1528: sigaddset(&bsigset, SIGQUIT) == -1 ||
1529: sigaddset(&bsigset, SIGTERM) == -1)
1530: error_f("bsigset setup: %s", strerror(errno));
1531:
1.11 markus 1532: /* Main loop of the client for the interactive session mode. */
1533: while (!quit_pending) {
1.396 djm 1534: channel_did_enqueue = 0;
1.11 markus 1535:
1.13 markus 1536: /* Process buffered packets sent by the server. */
1.321 djm 1537: client_process_buffered_input_packets(ssh);
1.11 markus 1538:
1.303 djm 1539: if (session_closed && !channel_still_open(ssh))
1.60 markus 1540: break;
1541:
1.303 djm 1542: if (ssh_packet_is_rekeying(ssh)) {
1.56 markus 1543: debug("rekeying in progress");
1.284 djm 1544: } else if (need_rekeying) {
1545: /* manual rekey request */
1546: debug("need rekeying");
1.303 djm 1547: if ((r = kex_start_rekex(ssh)) != 0)
1.354 djm 1548: fatal_fr(r, "kex_start_rekex");
1.284 djm 1549: need_rekeying = 0;
1.56 markus 1550: } else {
1551: /*
1552: * Make packets from buffered channel data, and
1553: * enqueue them for sending to the server.
1554: */
1.320 djm 1555: if (ssh_packet_not_very_much_data_to_write(ssh))
1.396 djm 1556: channel_did_enqueue = channel_output_poll(ssh);
1.11 markus 1557:
1.56 markus 1558: /*
1559: * Check if the window size has changed, and buffer a
1560: * message about it to the server if so.
1561: */
1.303 djm 1562: client_check_window_change(ssh);
1.56 markus 1563: }
1.13 markus 1564: /*
1565: * Wait until we have something to do (something becomes
1566: * available on one of the descriptors).
1567: */
1.400 djm 1568: if (sigprocmask(SIG_BLOCK, &bsigset, &osigset) == -1)
1569: error_f("bsigset sigprocmask: %s", strerror(errno));
1570: if (quit_pending)
1571: break;
1.374 djm 1572: client_wait_until_can_do_something(ssh, &pfd, &npfd_alloc,
1.400 djm 1573: &npfd_active, channel_did_enqueue, &osigset,
1.374 djm 1574: &conn_in_ready, &conn_out_ready);
1.405 djm 1575: if (sigprocmask(SIG_SETMASK, &osigset, NULL) == -1)
1.400 djm 1576: error_f("osigset sigprocmask: %s", strerror(errno));
1.11 markus 1577:
1578: if (quit_pending)
1579: break;
1580:
1.379 djm 1581: /* Do channel operations. */
1582: channel_after_poll(ssh, pfd, npfd_active);
1.11 markus 1583:
1.17 markus 1584: /* Buffer input from the connection. */
1.374 djm 1585: if (conn_in_ready)
1586: client_process_net_input(ssh);
1.17 markus 1587:
1588: if (quit_pending)
1589: break;
1.367 djm 1590:
1591: /* A timeout may have triggered rekeying */
1592: if ((r = ssh_packet_check_rekey(ssh)) != 0)
1593: fatal_fr(r, "cannot start rekeying");
1.11 markus 1594:
1.197 djm 1595: /*
1596: * Send as much buffered packet data as possible to the
1597: * sender.
1598: */
1.374 djm 1599: if (conn_out_ready) {
1.338 djm 1600: if ((r = ssh_packet_write_poll(ssh)) != 0) {
1601: sshpkt_fatal(ssh, r,
1602: "%s: ssh_packet_write_poll", __func__);
1603: }
1604: }
1.222 djm 1605:
1606: /*
1607: * If we are a backgrounded control master, and the
1608: * timeout has expired without any active client
1609: * connections, then quit.
1610: */
1611: if (control_persist_exit_time > 0) {
1.251 dtucker 1612: if (monotime() >= control_persist_exit_time) {
1.222 djm 1613: debug("ControlPersist timeout expired");
1614: break;
1615: }
1616: }
1.11 markus 1617: }
1.374 djm 1618: free(pfd);
1.11 markus 1619:
1620: /* Terminate the session. */
1621:
1.406 ! djm 1622: /*
! 1623: * In interactive mode (with pseudo tty) display a message indicating
! 1624: * that the connection has been closed.
! 1625: */
! 1626: if (have_pty && options.log_level >= SYSLOG_LEVEL_INFO)
! 1627: quit_message("Connection to %s closed.", host);
! 1628:
! 1629:
1.11 markus 1630: /* Stop watching for window change. */
1.332 dtucker 1631: ssh_signal(SIGWINCH, SIG_DFL);
1.211 andreas 1632:
1.320 djm 1633: if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
1634: (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_BY_APPLICATION)) != 0 ||
1635: (r = sshpkt_put_cstring(ssh, "disconnected by user")) != 0 ||
1636: (r = sshpkt_put_cstring(ssh, "")) != 0 || /* language tag */
1637: (r = sshpkt_send(ssh)) != 0 ||
1638: (r = ssh_packet_write_wait(ssh)) != 0)
1.354 djm 1639: fatal_fr(r, "send disconnect");
1.11 markus 1640:
1.303 djm 1641: channel_free_all(ssh);
1.11 markus 1642:
1.75 markus 1643: if (have_pty)
1.233 djm 1644: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.116 dtucker 1645:
1646: /*
1647: * If there was no shell or command requested, there will be no remote
1648: * exit status to be returned. In that case, clear error code if the
1649: * connection was deliberately terminated at this end.
1650: */
1.370 djm 1651: if (options.session_type == SESSION_TYPE_NONE &&
1652: received_signal == SIGTERM) {
1.116 dtucker 1653: received_signal = 0;
1654: exit_status = 0;
1655: }
1.75 markus 1656:
1.301 dtucker 1657: if (received_signal) {
1658: verbose("Killed by signal %d.", (int) received_signal);
1.359 djm 1659: cleanup_exit(255);
1.301 dtucker 1660: }
1.11 markus 1661:
1662: /* Report bytes transferred, and transfer rates. */
1.307 dtucker 1663: total_time = monotime_double() - start_time;
1.320 djm 1664: ssh_packet_get_bytes(ssh, &ibytes, &obytes);
1.200 markus 1665: verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
1.229 djm 1666: (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
1.11 markus 1667: if (total_time > 0)
1.200 markus 1668: verbose("Bytes per second: sent %.1f, received %.1f",
1669: obytes / total_time, ibytes / total_time);
1.11 markus 1670: /* Return the exit status of the program. */
1671: debug("Exit status %d", exit_status);
1672: return exit_status;
1.15 markus 1673: }
1674:
1675: /*********/
1676:
1.77 itojun 1677: static Channel *
1.303 djm 1678: client_request_forwarded_tcpip(struct ssh *ssh, const char *request_type,
1679: int rchan, u_int rwindow, u_int rmaxpack)
1.40 markus 1680: {
1.103 deraadt 1681: Channel *c = NULL;
1.289 markus 1682: struct sshbuf *b = NULL;
1.40 markus 1683: char *listen_address, *originator_address;
1.320 djm 1684: u_int listen_port, originator_port;
1.289 markus 1685: int r;
1.40 markus 1686:
1687: /* Get rest of the packet */
1.320 djm 1688: if ((r = sshpkt_get_cstring(ssh, &listen_address, NULL)) != 0 ||
1689: (r = sshpkt_get_u32(ssh, &listen_port)) != 0 ||
1690: (r = sshpkt_get_cstring(ssh, &originator_address, NULL)) != 0 ||
1691: (r = sshpkt_get_u32(ssh, &originator_port)) != 0 ||
1692: (r = sshpkt_get_end(ssh)) != 0)
1.354 djm 1693: fatal_fr(r, "parse packet");
1.40 markus 1694:
1.354 djm 1695: debug_f("listen %s port %d, originator %s port %d",
1.261 millert 1696: listen_address, listen_port, originator_address, originator_port);
1.191 djm 1697:
1.320 djm 1698: if (listen_port > 0xffff)
1.354 djm 1699: error_f("invalid listen port");
1.320 djm 1700: else if (originator_port > 0xffff)
1.354 djm 1701: error_f("invalid originator port");
1.320 djm 1702: else {
1703: c = channel_connect_by_listen_address(ssh,
1704: listen_address, listen_port, "forwarded-tcpip",
1705: originator_address);
1706: }
1.40 markus 1707:
1.289 markus 1708: if (c != NULL && c->type == SSH_CHANNEL_MUX_CLIENT) {
1709: if ((b = sshbuf_new()) == NULL) {
1.354 djm 1710: error_f("alloc reply");
1.289 markus 1711: goto out;
1712: }
1713: /* reconstruct and send to muxclient */
1714: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
1715: (r = sshbuf_put_u8(b, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
1716: (r = sshbuf_put_cstring(b, request_type)) != 0 ||
1717: (r = sshbuf_put_u32(b, rchan)) != 0 ||
1718: (r = sshbuf_put_u32(b, rwindow)) != 0 ||
1719: (r = sshbuf_put_u32(b, rmaxpack)) != 0 ||
1720: (r = sshbuf_put_cstring(b, listen_address)) != 0 ||
1721: (r = sshbuf_put_u32(b, listen_port)) != 0 ||
1722: (r = sshbuf_put_cstring(b, originator_address)) != 0 ||
1723: (r = sshbuf_put_u32(b, originator_port)) != 0 ||
1.303 djm 1724: (r = sshbuf_put_stringb(c->output, b)) != 0) {
1.354 djm 1725: error_fr(r, "compose for muxclient");
1.289 markus 1726: goto out;
1727: }
1728: }
1729:
1730: out:
1731: sshbuf_free(b);
1.250 djm 1732: free(originator_address);
1733: free(listen_address);
1.40 markus 1734: return c;
1735: }
1736:
1.103 deraadt 1737: static Channel *
1.303 djm 1738: client_request_forwarded_streamlocal(struct ssh *ssh,
1739: const char *request_type, int rchan)
1.261 millert 1740: {
1741: Channel *c = NULL;
1742: char *listen_path;
1.320 djm 1743: int r;
1.261 millert 1744:
1745: /* Get the remote path. */
1.320 djm 1746: if ((r = sshpkt_get_cstring(ssh, &listen_path, NULL)) != 0 ||
1747: (r = sshpkt_get_string(ssh, NULL, NULL)) != 0 || /* reserved */
1748: (r = sshpkt_get_end(ssh)) != 0)
1.354 djm 1749: fatal_fr(r, "parse packet");
1.261 millert 1750:
1.354 djm 1751: debug_f("request: %s", listen_path);
1.261 millert 1752:
1.303 djm 1753: c = channel_connect_by_listen_path(ssh, listen_path,
1.261 millert 1754: "forwarded-streamlocal@openssh.com", "forwarded-streamlocal");
1755: free(listen_path);
1756: return c;
1757: }
1758:
1759: static Channel *
1.303 djm 1760: client_request_x11(struct ssh *ssh, const char *request_type, int rchan)
1.40 markus 1761: {
1762: Channel *c = NULL;
1763: char *originator;
1.321 djm 1764: u_int originator_port;
1.320 djm 1765: int r, sock;
1.40 markus 1766:
1767: if (!options.forward_x11) {
1768: error("Warning: ssh server tried X11 forwarding.");
1.197 djm 1769: error("Warning: this is probably a break-in attempt by a "
1770: "malicious server.");
1.221 djm 1771: return NULL;
1772: }
1.388 dtucker 1773: if (x11_refuse_time != 0 && monotime() >= x11_refuse_time) {
1.221 djm 1774: verbose("Rejected X11 connection after ForwardX11Timeout "
1775: "expired");
1.40 markus 1776: return NULL;
1777: }
1.320 djm 1778: if ((r = sshpkt_get_cstring(ssh, &originator, NULL)) != 0 ||
1.321 djm 1779: (r = sshpkt_get_u32(ssh, &originator_port)) != 0 ||
1.320 djm 1780: (r = sshpkt_get_end(ssh)) != 0)
1.354 djm 1781: fatal_fr(r, "parse packet");
1.40 markus 1782: /* XXX check permission */
1.321 djm 1783: /* XXX range check originator port? */
1784: debug("client_request_x11: request from %s %u", originator,
1.47 markus 1785: originator_port);
1.250 djm 1786: free(originator);
1.303 djm 1787: sock = x11_connect_display(ssh);
1.67 markus 1788: if (sock < 0)
1789: return NULL;
1.399 djm 1790: c = channel_new(ssh, "x11-connection",
1.67 markus 1791: SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1.110 markus 1792: CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1.82 markus 1793: c->force_drain = 1;
1.40 markus 1794: return c;
1795: }
1796:
1.103 deraadt 1797: static Channel *
1.303 djm 1798: client_request_agent(struct ssh *ssh, const char *request_type, int rchan)
1.40 markus 1799: {
1800: Channel *c = NULL;
1.262 djm 1801: int r, sock;
1.40 markus 1802:
1803: if (!options.forward_agent) {
1804: error("Warning: ssh server tried agent forwarding.");
1.197 djm 1805: error("Warning: this is probably a break-in attempt by a "
1806: "malicious server.");
1.40 markus 1807: return NULL;
1808: }
1.330 djm 1809: if (forward_agent_sock_path == NULL) {
1810: r = ssh_get_authentication_socket(&sock);
1811: } else {
1812: r = ssh_get_authentication_socket_path(forward_agent_sock_path, &sock);
1813: }
1814: if (r != 0) {
1.262 djm 1815: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1.354 djm 1816: debug_fr(r, "ssh_get_authentication_socket");
1.67 markus 1817: return NULL;
1.262 djm 1818: }
1.372 djm 1819: if ((r = ssh_agent_bind_hostkey(sock, ssh->kex->initial_hostkey,
1820: ssh->kex->session_id, ssh->kex->initial_sig, 1)) == 0)
1821: debug_f("bound agent to hostkey");
1822: else
1823: debug2_fr(r, "ssh_agent_bind_hostkey");
1824:
1.399 djm 1825: c = channel_new(ssh, "agent-connection",
1.67 markus 1826: SSH_CHANNEL_OPEN, sock, sock, -1,
1.185 dtucker 1827: CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0,
1.110 markus 1828: "authentication agent connection", 1);
1.82 markus 1829: c->force_drain = 1;
1.40 markus 1830: return c;
1.180 djm 1831: }
1832:
1.306 djm 1833: char *
1.303 djm 1834: client_request_tun_fwd(struct ssh *ssh, int tun_mode,
1.343 djm 1835: int local_tun, int remote_tun, channel_open_fn *cb, void *cbctx)
1.180 djm 1836: {
1837: Channel *c;
1.320 djm 1838: int r, fd;
1.306 djm 1839: char *ifname = NULL;
1.180 djm 1840:
1841: if (tun_mode == SSH_TUNMODE_NO)
1842: return 0;
1843:
1844: debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
1845:
1846: /* Open local tunnel device */
1.306 djm 1847: if ((fd = tun_open(local_tun, tun_mode, &ifname)) == -1) {
1.180 djm 1848: error("Tunnel device open failed.");
1.306 djm 1849: return NULL;
1.180 djm 1850: }
1.306 djm 1851: debug("Tunnel forwarding using interface %s", ifname);
1.180 djm 1852:
1.399 djm 1853: c = channel_new(ssh, "tun-connection", SSH_CHANNEL_OPENING, fd, fd, -1,
1.180 djm 1854: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1);
1855: c->datagram = 1;
1.343 djm 1856:
1857: if (cb != NULL)
1858: channel_register_open_confirm(ssh, c->self, cb, cbctx);
1.180 djm 1859:
1.320 djm 1860: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
1861: (r = sshpkt_put_cstring(ssh, "tun@openssh.com")) != 0 ||
1862: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1863: (r = sshpkt_put_u32(ssh, c->local_window_max)) != 0 ||
1864: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0 ||
1865: (r = sshpkt_put_u32(ssh, tun_mode)) != 0 ||
1866: (r = sshpkt_put_u32(ssh, remote_tun)) != 0 ||
1867: (r = sshpkt_send(ssh)) != 0)
1.321 djm 1868: sshpkt_fatal(ssh, r, "%s: send reply", __func__);
1.180 djm 1869:
1.306 djm 1870: return ifname;
1.40 markus 1871: }
1872:
1.22 markus 1873: /* XXXX move to generic input handler */
1.264 markus 1874: static int
1.297 markus 1875: client_input_channel_open(int type, u_int32_t seq, struct ssh *ssh)
1.22 markus 1876: {
1877: Channel *c = NULL;
1.320 djm 1878: char *ctype = NULL;
1879: int r;
1880: u_int rchan;
1881: size_t len;
1882: u_int rmaxpack, rwindow;
1883:
1884: if ((r = sshpkt_get_cstring(ssh, &ctype, &len)) != 0 ||
1885: (r = sshpkt_get_u32(ssh, &rchan)) != 0 ||
1886: (r = sshpkt_get_u32(ssh, &rwindow)) != 0 ||
1887: (r = sshpkt_get_u32(ssh, &rmaxpack)) != 0)
1888: goto out;
1.22 markus 1889:
1.24 markus 1890: debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1.22 markus 1891: ctype, rchan, rwindow, rmaxpack);
1892:
1.40 markus 1893: if (strcmp(ctype, "forwarded-tcpip") == 0) {
1.303 djm 1894: c = client_request_forwarded_tcpip(ssh, ctype, rchan, rwindow,
1.289 markus 1895: rmaxpack);
1.261 millert 1896: } else if (strcmp(ctype, "forwarded-streamlocal@openssh.com") == 0) {
1.303 djm 1897: c = client_request_forwarded_streamlocal(ssh, ctype, rchan);
1.40 markus 1898: } else if (strcmp(ctype, "x11") == 0) {
1.303 djm 1899: c = client_request_x11(ssh, ctype, rchan);
1.40 markus 1900: } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1.303 djm 1901: c = client_request_agent(ssh, ctype, rchan);
1.22 markus 1902: }
1.289 markus 1903: if (c != NULL && c->type == SSH_CHANNEL_MUX_CLIENT) {
1904: debug3("proxied to downstream: %s", ctype);
1905: } else if (c != NULL) {
1.22 markus 1906: debug("confirm %s", ctype);
1907: c->remote_id = rchan;
1.304 djm 1908: c->have_remote_id = 1;
1.22 markus 1909: c->remote_window = rwindow;
1910: c->remote_maxpacket = rmaxpack;
1.69 markus 1911: if (c->type != SSH_CHANNEL_CONNECTING) {
1.320 djm 1912: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1913: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1914: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1915: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1916: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0 ||
1917: (r = sshpkt_send(ssh)) != 0)
1918: sshpkt_fatal(ssh, r, "%s: send reply", __func__);
1.69 markus 1919: }
1.22 markus 1920: } else {
1921: debug("failure %s", ctype);
1.320 djm 1922: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1923: (r = sshpkt_put_u32(ssh, rchan)) != 0 ||
1924: (r = sshpkt_put_u32(ssh, SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED)) != 0 ||
1925: (r = sshpkt_put_cstring(ssh, "open failed")) != 0 ||
1926: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1927: (r = sshpkt_send(ssh)) != 0)
1928: sshpkt_fatal(ssh, r, "%s: send failure", __func__);
1.22 markus 1929: }
1.320 djm 1930: r = 0;
1931: out:
1.250 djm 1932: free(ctype);
1.320 djm 1933: return r;
1.22 markus 1934: }
1.267 djm 1935:
1.264 markus 1936: static int
1.297 markus 1937: client_input_channel_req(int type, u_int32_t seq, struct ssh *ssh)
1.48 markus 1938: {
1939: Channel *c = NULL;
1.320 djm 1940: char *rtype = NULL;
1941: u_char reply;
1942: u_int id, exitval;
1943: int r, success = 0;
1944:
1945: if ((r = sshpkt_get_u32(ssh, &id)) != 0)
1946: return r;
1947: if (id <= INT_MAX)
1948: c = channel_lookup(ssh, id);
1.297 markus 1949: if (channel_proxy_upstream(c, type, seq, ssh))
1.289 markus 1950: return 0;
1.320 djm 1951: if ((r = sshpkt_get_cstring(ssh, &rtype, NULL)) != 0 ||
1952: (r = sshpkt_get_u8(ssh, &reply)) != 0)
1953: goto out;
1.48 markus 1954:
1.320 djm 1955: debug("client_input_channel_req: channel %u rtype %s reply %d",
1.48 markus 1956: id, rtype, reply);
1957:
1.320 djm 1958: if (c == NULL) {
1.197 djm 1959: error("client_input_channel_req: channel %d: "
1960: "unknown channel", id);
1.193 markus 1961: } else if (strcmp(rtype, "eow@openssh.com") == 0) {
1.320 djm 1962: if ((r = sshpkt_get_end(ssh)) != 0)
1963: goto out;
1.303 djm 1964: chan_rcvd_eow(ssh, c);
1.48 markus 1965: } else if (strcmp(rtype, "exit-status") == 0) {
1.320 djm 1966: if ((r = sshpkt_get_u32(ssh, &exitval)) != 0)
1967: goto out;
1.217 djm 1968: if (c->ctl_chan != -1) {
1.303 djm 1969: mux_exit_message(ssh, c, exitval);
1.215 djm 1970: success = 1;
1.320 djm 1971: } else if ((int)id == session_ident) {
1.215 djm 1972: /* Record exit value of local session */
1.123 djm 1973: success = 1;
1974: exit_status = exitval;
1.215 djm 1975: } else {
1.218 djm 1976: /* Probably for a mux channel that has already closed */
1.354 djm 1977: debug_f("no sink for exit-status on channel %d",
1978: id);
1.123 djm 1979: }
1.320 djm 1980: if ((r = sshpkt_get_end(ssh)) != 0)
1981: goto out;
1.48 markus 1982: }
1.259 djm 1983: if (reply && c != NULL && !(c->flags & CHAN_CLOSE_SENT)) {
1.304 djm 1984: if (!c->have_remote_id)
1.354 djm 1985: fatal_f("channel %d: no remote_id", c->self);
1.320 djm 1986: if ((r = sshpkt_start(ssh, success ?
1987: SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE)) != 0 ||
1988: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1989: (r = sshpkt_send(ssh)) != 0)
1990: sshpkt_fatal(ssh, r, "%s: send failure", __func__);
1.48 markus 1991: }
1.320 djm 1992: r = 0;
1993: out:
1.250 djm 1994: free(rtype);
1.320 djm 1995: return r;
1.48 markus 1996: }
1.267 djm 1997:
1.269 djm 1998: struct hostkeys_update_ctx {
1999: /* The hostname and (optionally) IP address string for the server */
2000: char *host_str, *ip_str;
2001:
2002: /*
2003: * Keys received from the server and a flag for each indicating
2004: * whether they already exist in known_hosts.
1.351 djm 2005: * keys_match is filled in by hostkeys_find() and later (for new
1.381 djm 2006: * keys) by client_global_hostkeys_prove_confirm().
1.269 djm 2007: */
2008: struct sshkey **keys;
1.351 djm 2009: u_int *keys_match; /* mask of HKF_MATCH_* from hostfile.h */
2010: int *keys_verified; /* flag for new keys verified by server */
2011: size_t nkeys, nnew, nincomplete; /* total, new keys, incomplete match */
1.269 djm 2012:
2013: /*
2014: * Keys that are in known_hosts, but were not present in the update
2015: * from the server (i.e. scheduled to be deleted).
2016: * Filled in by hostkeys_find().
2017: */
2018: struct sshkey **old_keys;
2019: size_t nold;
1.347 djm 2020:
2021: /* Various special cases. */
1.350 djm 2022: int complex_hostspec; /* wildcard or manual pattern-list host name */
1.347 djm 2023: int ca_available; /* saw CA key for this host */
1.352 djm 2024: int old_key_seen; /* saw old key with other name/addr */
1.353 djm 2025: int other_name_seen; /* saw key with other name/addr */
1.269 djm 2026: };
2027:
2028: static void
2029: hostkeys_update_ctx_free(struct hostkeys_update_ctx *ctx)
2030: {
2031: size_t i;
2032:
2033: if (ctx == NULL)
2034: return;
2035: for (i = 0; i < ctx->nkeys; i++)
2036: sshkey_free(ctx->keys[i]);
2037: free(ctx->keys);
1.351 djm 2038: free(ctx->keys_match);
2039: free(ctx->keys_verified);
1.269 djm 2040: for (i = 0; i < ctx->nold; i++)
2041: sshkey_free(ctx->old_keys[i]);
2042: free(ctx->old_keys);
2043: free(ctx->host_str);
2044: free(ctx->ip_str);
2045: free(ctx);
2046: }
2047:
1.350 djm 2048: /*
2049: * Returns non-zero if a known_hosts hostname list is not of a form that
2050: * can be handled by UpdateHostkeys. These include wildcard hostnames and
2051: * hostnames lists that do not follow the form host[,ip].
2052: */
2053: static int
2054: hostspec_is_complex(const char *hosts)
2055: {
2056: char *cp;
2057:
2058: /* wildcard */
2059: if (strchr(hosts, '*') != NULL || strchr(hosts, '?') != NULL)
2060: return 1;
2061: /* single host/ip = ok */
2062: if ((cp = strchr(hosts, ',')) == NULL)
2063: return 0;
2064: /* more than two entries on the line */
2065: if (strchr(cp + 1, ',') != NULL)
2066: return 1;
2067: /* XXX maybe parse cp+1 and ensure it is an IP? */
2068: return 0;
2069: }
2070:
1.352 djm 2071: /* callback to search for ctx->keys in known_hosts */
1.269 djm 2072: static int
2073: hostkeys_find(struct hostkey_foreach_line *l, void *_ctx)
2074: {
2075: struct hostkeys_update_ctx *ctx = (struct hostkeys_update_ctx *)_ctx;
2076: size_t i;
2077: struct sshkey **tmp;
2078:
1.353 djm 2079: if (l->key == NULL)
1.269 djm 2080: return 0;
1.353 djm 2081: if (l->status != HKF_STATUS_MATCHED) {
2082: /* Record if one of the keys appears on a non-matching line */
2083: for (i = 0; i < ctx->nkeys; i++) {
2084: if (sshkey_equal(l->key, ctx->keys[i])) {
2085: ctx->other_name_seen = 1;
1.354 djm 2086: debug3_f("found %s key under different "
2087: "name/addr at %s:%ld",
1.353 djm 2088: sshkey_ssh_name(ctx->keys[i]),
2089: l->path, l->linenum);
2090: return 0;
2091: }
2092: }
2093: return 0;
2094: }
2095: /* Don't proceed if revocation or CA markers are present */
2096: /* XXX relax this */
2097: if (l->marker != MRK_NONE) {
1.354 djm 2098: debug3_f("hostkeys file %s:%ld has CA/revocation marker",
2099: l->path, l->linenum);
1.353 djm 2100: ctx->complex_hostspec = 1;
2101: return 0;
2102: }
2103:
1.355 djm 2104: /* If CheckHostIP is enabled, then check for mismatched hostname/addr */
2105: if (ctx->ip_str != NULL && strchr(l->hosts, ',') != NULL) {
2106: if ((l->match & HKF_MATCH_HOST) == 0) {
2107: /* Record if address matched a different hostname. */
2108: ctx->other_name_seen = 1;
2109: debug3_f("found address %s against different hostname "
2110: "at %s:%ld", ctx->ip_str, l->path, l->linenum);
2111: return 0;
2112: } else if ((l->match & HKF_MATCH_IP) == 0) {
2113: /* Record if hostname matched a different address. */
2114: ctx->other_name_seen = 1;
2115: debug3_f("found hostname %s against different address "
2116: "at %s:%ld", ctx->host_str, l->path, l->linenum);
2117: }
1.353 djm 2118: }
1.269 djm 2119:
1.350 djm 2120: /*
2121: * UpdateHostkeys is skipped for wildcard host names and hostnames
2122: * that contain more than two entries (ssh never writes these).
2123: */
2124: if (hostspec_is_complex(l->hosts)) {
1.354 djm 2125: debug3_f("hostkeys file %s:%ld complex host specification",
2126: l->path, l->linenum);
1.350 djm 2127: ctx->complex_hostspec = 1;
1.347 djm 2128: return 0;
2129: }
2130:
1.269 djm 2131: /* Mark off keys we've already seen for this host */
2132: for (i = 0; i < ctx->nkeys; i++) {
1.351 djm 2133: if (!sshkey_equal(l->key, ctx->keys[i]))
2134: continue;
1.354 djm 2135: debug3_f("found %s key at %s:%ld",
1.351 djm 2136: sshkey_ssh_name(ctx->keys[i]), l->path, l->linenum);
2137: ctx->keys_match[i] |= l->match;
2138: return 0;
1.269 djm 2139: }
2140: /* This line contained a key that not offered by the server */
1.354 djm 2141: debug3_f("deprecated %s key at %s:%ld", sshkey_ssh_name(l->key),
2142: l->path, l->linenum);
1.299 deraadt 2143: if ((tmp = recallocarray(ctx->old_keys, ctx->nold, ctx->nold + 1,
1.269 djm 2144: sizeof(*ctx->old_keys))) == NULL)
1.354 djm 2145: fatal_f("recallocarray failed nold = %zu", ctx->nold);
1.269 djm 2146: ctx->old_keys = tmp;
2147: ctx->old_keys[ctx->nold++] = l->key;
2148: l->key = NULL;
2149:
2150: return 0;
2151: }
2152:
1.352 djm 2153: /* callback to search for ctx->old_keys in known_hosts under other names */
2154: static int
2155: hostkeys_check_old(struct hostkey_foreach_line *l, void *_ctx)
2156: {
2157: struct hostkeys_update_ctx *ctx = (struct hostkeys_update_ctx *)_ctx;
2158: size_t i;
2159: int hashed;
2160:
2161: /* only care about lines that *don't* match the active host spec */
2162: if (l->status == HKF_STATUS_MATCHED || l->key == NULL)
2163: return 0;
2164:
2165: hashed = l->match & (HKF_MATCH_HOST_HASHED|HKF_MATCH_IP_HASHED);
2166: for (i = 0; i < ctx->nold; i++) {
2167: if (!sshkey_equal(l->key, ctx->old_keys[i]))
2168: continue;
1.354 djm 2169: debug3_f("found deprecated %s key at %s:%ld as %s",
1.364 djm 2170: sshkey_ssh_name(ctx->old_keys[i]), l->path, l->linenum,
1.352 djm 2171: hashed ? "[HASHED]" : l->hosts);
2172: ctx->old_key_seen = 1;
2173: break;
2174: }
2175: return 0;
2176: }
2177:
2178: /*
2179: * Check known_hosts files for deprecated keys under other names. Returns 0
2180: * on success or -1 on failure. Updates ctx->old_key_seen if deprecated keys
2181: * exist under names other than the active hostname/IP.
2182: */
2183: static int
2184: check_old_keys_othernames(struct hostkeys_update_ctx *ctx)
2185: {
2186: size_t i;
2187: int r;
2188:
1.354 djm 2189: debug2_f("checking for %zu deprecated keys", ctx->nold);
1.352 djm 2190: for (i = 0; i < options.num_user_hostfiles; i++) {
1.354 djm 2191: debug3_f("searching %s for %s / %s",
1.352 djm 2192: options.user_hostfiles[i], ctx->host_str,
2193: ctx->ip_str ? ctx->ip_str : "(none)");
2194: if ((r = hostkeys_foreach(options.user_hostfiles[i],
2195: hostkeys_check_old, ctx, ctx->host_str, ctx->ip_str,
1.356 djm 2196: HKF_WANT_PARSE_KEY, 0)) != 0) {
1.352 djm 2197: if (r == SSH_ERR_SYSTEM_ERROR && errno == ENOENT) {
1.354 djm 2198: debug_f("hostkeys file %s does not exist",
2199: options.user_hostfiles[i]);
1.352 djm 2200: continue;
2201: }
1.354 djm 2202: error_fr(r, "hostkeys_foreach failed for %s",
2203: options.user_hostfiles[i]);
1.352 djm 2204: return -1;
2205: }
2206: }
2207: return 0;
2208: }
2209:
1.269 djm 2210: static void
1.337 djm 2211: hostkey_change_preamble(LogLevel loglevel)
1.269 djm 2212: {
1.336 djm 2213: do_log2(loglevel, "The server has updated its host keys.");
2214: do_log2(loglevel, "These changes were verified by the server's "
2215: "existing trusted key.");
2216: }
2217:
2218: static void
2219: update_known_hosts(struct hostkeys_update_ctx *ctx)
2220: {
2221: int r, was_raw = 0, first = 1;
2222: int asking = options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK;
2223: LogLevel loglevel = asking ? SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_VERBOSE;
1.269 djm 2224: char *fp, *response;
2225: size_t i;
1.333 djm 2226: struct stat sb;
1.269 djm 2227:
2228: for (i = 0; i < ctx->nkeys; i++) {
1.351 djm 2229: if (!ctx->keys_verified[i])
1.269 djm 2230: continue;
2231: if ((fp = sshkey_fingerprint(ctx->keys[i],
2232: options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
1.354 djm 2233: fatal_f("sshkey_fingerprint failed");
1.336 djm 2234: if (first && asking)
1.337 djm 2235: hostkey_change_preamble(loglevel);
1.269 djm 2236: do_log2(loglevel, "Learned new hostkey: %s %s",
2237: sshkey_type(ctx->keys[i]), fp);
1.336 djm 2238: first = 0;
1.269 djm 2239: free(fp);
2240: }
2241: for (i = 0; i < ctx->nold; i++) {
2242: if ((fp = sshkey_fingerprint(ctx->old_keys[i],
2243: options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
1.354 djm 2244: fatal_f("sshkey_fingerprint failed");
1.336 djm 2245: if (first && asking)
1.337 djm 2246: hostkey_change_preamble(loglevel);
1.269 djm 2247: do_log2(loglevel, "Deprecating obsolete hostkey: %s %s",
2248: sshkey_type(ctx->old_keys[i]), fp);
1.336 djm 2249: first = 0;
1.269 djm 2250: free(fp);
2251: }
2252: if (options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) {
1.271 djm 2253: if (get_saved_tio() != NULL) {
2254: leave_raw_mode(1);
2255: was_raw = 1;
2256: }
1.269 djm 2257: response = NULL;
2258: for (i = 0; !quit_pending && i < 3; i++) {
2259: free(response);
2260: response = read_passphrase("Accept updated hostkeys? "
2261: "(yes/no): ", RP_ECHO);
1.389 dtucker 2262: if (response != NULL && strcasecmp(response, "yes") == 0)
1.269 djm 2263: break;
2264: else if (quit_pending || response == NULL ||
2265: strcasecmp(response, "no") == 0) {
2266: options.update_hostkeys = 0;
2267: break;
2268: } else {
2269: do_log2(loglevel, "Please enter "
2270: "\"yes\" or \"no\"");
2271: }
2272: }
2273: if (quit_pending || i >= 3 || response == NULL)
2274: options.update_hostkeys = 0;
2275: free(response);
1.271 djm 2276: if (was_raw)
2277: enter_raw_mode(1);
1.269 djm 2278: }
1.333 djm 2279: if (options.update_hostkeys == 0)
2280: return;
1.269 djm 2281: /*
2282: * Now that all the keys are verified, we can go ahead and replace
2283: * them in known_hosts (assuming SSH_UPDATE_HOSTKEYS_ASK didn't
2284: * cancel the operation).
2285: */
1.333 djm 2286: for (i = 0; i < options.num_user_hostfiles; i++) {
2287: /*
2288: * NB. keys are only added to hostfiles[0], for the rest we
2289: * just delete the hostname entries.
2290: */
2291: if (stat(options.user_hostfiles[i], &sb) != 0) {
2292: if (errno == ENOENT) {
1.354 djm 2293: debug_f("known hosts file %s does not "
2294: "exist", options.user_hostfiles[i]);
1.333 djm 2295: } else {
1.354 djm 2296: error_f("known hosts file %s "
2297: "inaccessible: %s",
2298: options.user_hostfiles[i], strerror(errno));
1.333 djm 2299: }
2300: continue;
2301: }
2302: if ((r = hostfile_replace_entries(options.user_hostfiles[i],
2303: ctx->host_str, ctx->ip_str,
2304: i == 0 ? ctx->keys : NULL, i == 0 ? ctx->nkeys : 0,
2305: options.hash_known_hosts, 0,
2306: options.fingerprint_hash)) != 0) {
1.354 djm 2307: error_fr(r, "hostfile_replace_entries failed for %s",
2308: options.user_hostfiles[i]);
1.333 djm 2309: }
2310: }
1.269 djm 2311: }
2312:
2313: static void
1.381 djm 2314: client_global_hostkeys_prove_confirm(struct ssh *ssh, int type,
1.303 djm 2315: u_int32_t seq, void *_ctx)
1.269 djm 2316: {
2317: struct hostkeys_update_ctx *ctx = (struct hostkeys_update_ctx *)_ctx;
2318: size_t i, ndone;
2319: struct sshbuf *signdata;
1.375 djm 2320: int r, plaintype;
1.269 djm 2321: const u_char *sig;
1.375 djm 2322: const char *rsa_kexalg = NULL;
2323: char *alg = NULL;
1.269 djm 2324: size_t siglen;
2325:
2326: if (ctx->nnew == 0)
1.354 djm 2327: fatal_f("ctx->nnew == 0"); /* sanity */
1.269 djm 2328: if (type != SSH2_MSG_REQUEST_SUCCESS) {
2329: error("Server failed to confirm ownership of "
2330: "private host keys");
2331: hostkeys_update_ctx_free(ctx);
2332: return;
2333: }
1.375 djm 2334: if (sshkey_type_plain(sshkey_type_from_name(
2335: ssh->kex->hostkey_alg)) == KEY_RSA)
2336: rsa_kexalg = ssh->kex->hostkey_alg;
1.269 djm 2337: if ((signdata = sshbuf_new()) == NULL)
1.354 djm 2338: fatal_f("sshbuf_new failed");
1.269 djm 2339: /*
2340: * Expect a signature for each of the ctx->nnew private keys we
2341: * haven't seen before. They will be in the same order as the
1.351 djm 2342: * ctx->keys where the corresponding ctx->keys_match[i] == 0.
1.269 djm 2343: */
2344: for (ndone = i = 0; i < ctx->nkeys; i++) {
1.351 djm 2345: if (ctx->keys_match[i])
1.269 djm 2346: continue;
1.375 djm 2347: plaintype = sshkey_type_plain(ctx->keys[i]->type);
1.269 djm 2348: /* Prepare data to be signed: session ID, unique string, key */
2349: sshbuf_reset(signdata);
1.270 djm 2350: if ( (r = sshbuf_put_cstring(signdata,
2351: "hostkeys-prove-00@openssh.com")) != 0 ||
1.358 djm 2352: (r = sshbuf_put_stringb(signdata,
2353: ssh->kex->session_id)) != 0 ||
1.269 djm 2354: (r = sshkey_puts(ctx->keys[i], signdata)) != 0)
1.354 djm 2355: fatal_fr(r, "compose signdata");
1.269 djm 2356: /* Extract and verify signature */
2357: if ((r = sshpkt_get_string_direct(ssh, &sig, &siglen)) != 0) {
1.354 djm 2358: error_fr(r, "parse sig");
1.269 djm 2359: goto out;
2360: }
1.375 djm 2361: if ((r = sshkey_get_sigtype(sig, siglen, &alg)) != 0) {
2362: error_fr(r, "server gave unintelligible signature "
2363: "for %s key %zu", sshkey_type(ctx->keys[i]), i);
2364: goto out;
2365: }
1.309 djm 2366: /*
1.375 djm 2367: * Special case for RSA keys: if a RSA hostkey was negotiated,
2368: * then use its signature type for verification of RSA hostkey
2369: * proofs. Otherwise, accept only RSA-SHA256/512 signatures.
1.309 djm 2370: */
1.375 djm 2371: if (plaintype == KEY_RSA && rsa_kexalg == NULL &&
2372: match_pattern_list(alg, HOSTKEY_PROOF_RSA_ALGS, 0) != 1) {
2373: debug_f("server used untrusted RSA signature algorithm "
2374: "%s for key %zu, disregarding", alg, i);
2375: free(alg);
2376: /* zap the key from the list */
2377: sshkey_free(ctx->keys[i]);
2378: ctx->keys[i] = NULL;
2379: ndone++;
2380: continue;
2381: }
2382: debug3_f("verify %s key %zu using sigalg %s",
2383: sshkey_type(ctx->keys[i]), i, alg);
2384: free(alg);
1.269 djm 2385: if ((r = sshkey_verify(ctx->keys[i], sig, siglen,
1.308 djm 2386: sshbuf_ptr(signdata), sshbuf_len(signdata),
1.375 djm 2387: plaintype == KEY_RSA ? rsa_kexalg : NULL, 0, NULL)) != 0) {
1.361 djm 2388: error_fr(r, "server gave bad signature for %s key %zu",
1.354 djm 2389: sshkey_type(ctx->keys[i]), i);
1.269 djm 2390: goto out;
2391: }
2392: /* Key is good. Mark it as 'seen' */
1.351 djm 2393: ctx->keys_verified[i] = 1;
1.269 djm 2394: ndone++;
2395: }
1.354 djm 2396: /* Shouldn't happen */
1.269 djm 2397: if (ndone != ctx->nnew)
1.354 djm 2398: fatal_f("ndone != ctx->nnew (%zu / %zu)", ndone, ctx->nnew);
1.320 djm 2399: if ((r = sshpkt_get_end(ssh)) != 0) {
1.354 djm 2400: error_f("protocol error");
1.320 djm 2401: goto out;
2402: }
1.269 djm 2403:
2404: /* Make the edits to known_hosts */
2405: update_known_hosts(ctx);
2406: out:
2407: hostkeys_update_ctx_free(ctx);
1.384 djm 2408: hostkeys_update_complete = 1;
2409: client_repledge();
1.269 djm 2410: }
2411:
1.267 djm 2412: /*
1.270 djm 2413: * Handle hostkeys-00@openssh.com global request to inform the client of all
1.267 djm 2414: * the server's hostkeys. The keys are checked against the user's
2415: * HostkeyAlgorithms preference before they are accepted.
2416: */
2417: static int
1.321 djm 2418: client_input_hostkeys(struct ssh *ssh)
1.267 djm 2419: {
2420: const u_char *blob = NULL;
1.269 djm 2421: size_t i, len = 0;
1.267 djm 2422: struct sshbuf *buf = NULL;
1.269 djm 2423: struct sshkey *key = NULL, **tmp;
1.384 djm 2424: int r, prove_sent = 0;
1.269 djm 2425: char *fp;
1.267 djm 2426: static int hostkeys_seen = 0; /* XXX use struct ssh */
1.268 djm 2427: extern struct sockaddr_storage hostaddr; /* XXX from ssh.c */
1.272 djm 2428: struct hostkeys_update_ctx *ctx = NULL;
1.351 djm 2429: u_int want;
1.267 djm 2430:
2431: if (hostkeys_seen)
1.354 djm 2432: fatal_f("server already sent hostkeys");
1.384 djm 2433: if (!can_update_hostkeys())
1.267 djm 2434: return 1;
1.384 djm 2435: hostkeys_seen = 1;
1.272 djm 2436:
2437: ctx = xcalloc(1, sizeof(*ctx));
1.269 djm 2438: while (ssh_packet_remaining(ssh) > 0) {
1.267 djm 2439: sshkey_free(key);
2440: key = NULL;
1.269 djm 2441: if ((r = sshpkt_get_string_direct(ssh, &blob, &len)) != 0) {
1.354 djm 2442: error_fr(r, "parse key");
1.269 djm 2443: goto out;
2444: }
1.270 djm 2445: if ((r = sshkey_from_blob(blob, len, &key)) != 0) {
1.354 djm 2446: do_log2_fr(r, r == SSH_ERR_KEY_TYPE_UNKNOWN ?
1.335 djm 2447: SYSLOG_LEVEL_DEBUG1 : SYSLOG_LEVEL_ERROR,
1.354 djm 2448: "convert key");
1.335 djm 2449: continue;
1.270 djm 2450: }
1.267 djm 2451: fp = sshkey_fingerprint(key, options.fingerprint_hash,
2452: SSH_FP_DEFAULT);
1.354 djm 2453: debug3_f("received %s key %s", sshkey_type(key), fp);
1.267 djm 2454: free(fp);
1.275 markus 2455:
1.404 djm 2456: if (!hostkey_accepted_by_hostkeyalgs(key)) {
1.354 djm 2457: debug3_f("%s key not permitted by "
2458: "HostkeyAlgorithms", sshkey_ssh_name(key));
1.267 djm 2459: continue;
2460: }
1.269 djm 2461: /* Skip certs */
2462: if (sshkey_is_cert(key)) {
1.354 djm 2463: debug3_f("%s key is a certificate; skipping",
2464: sshkey_ssh_name(key));
1.269 djm 2465: continue;
2466: }
2467: /* Ensure keys are unique */
2468: for (i = 0; i < ctx->nkeys; i++) {
2469: if (sshkey_equal(key, ctx->keys[i])) {
1.354 djm 2470: error_f("received duplicated %s host key",
2471: sshkey_ssh_name(key));
1.269 djm 2472: goto out;
2473: }
2474: }
2475: /* Key is good, record it */
1.299 deraadt 2476: if ((tmp = recallocarray(ctx->keys, ctx->nkeys, ctx->nkeys + 1,
1.269 djm 2477: sizeof(*ctx->keys))) == NULL)
1.354 djm 2478: fatal_f("recallocarray failed nkeys = %zu",
2479: ctx->nkeys);
1.269 djm 2480: ctx->keys = tmp;
2481: ctx->keys[ctx->nkeys++] = key;
1.267 djm 2482: key = NULL;
2483: }
2484:
1.269 djm 2485: if (ctx->nkeys == 0) {
1.354 djm 2486: debug_f("server sent no hostkeys");
1.267 djm 2487: goto out;
2488: }
1.270 djm 2489:
1.351 djm 2490: if ((ctx->keys_match = calloc(ctx->nkeys,
2491: sizeof(*ctx->keys_match))) == NULL ||
2492: (ctx->keys_verified = calloc(ctx->nkeys,
2493: sizeof(*ctx->keys_verified))) == NULL)
1.354 djm 2494: fatal_f("calloc failed");
1.267 djm 2495:
1.268 djm 2496: get_hostfile_hostname_ipaddr(host,
2497: options.check_host_ip ? (struct sockaddr *)&hostaddr : NULL,
1.269 djm 2498: options.port, &ctx->host_str,
2499: options.check_host_ip ? &ctx->ip_str : NULL);
1.268 djm 2500:
1.269 djm 2501: /* Find which keys we already know about. */
1.333 djm 2502: for (i = 0; i < options.num_user_hostfiles; i++) {
1.354 djm 2503: debug_f("searching %s for %s / %s",
1.339 dtucker 2504: options.user_hostfiles[i], ctx->host_str,
1.340 dtucker 2505: ctx->ip_str ? ctx->ip_str : "(none)");
1.333 djm 2506: if ((r = hostkeys_foreach(options.user_hostfiles[i],
2507: hostkeys_find, ctx, ctx->host_str, ctx->ip_str,
1.356 djm 2508: HKF_WANT_PARSE_KEY, 0)) != 0) {
1.333 djm 2509: if (r == SSH_ERR_SYSTEM_ERROR && errno == ENOENT) {
1.354 djm 2510: debug_f("hostkeys file %s does not exist",
2511: options.user_hostfiles[i]);
1.333 djm 2512: continue;
2513: }
1.354 djm 2514: error_fr(r, "hostkeys_foreach failed for %s",
2515: options.user_hostfiles[i]);
1.333 djm 2516: goto out;
2517: }
1.267 djm 2518: }
2519:
1.269 djm 2520: /* Figure out if we have any new keys to add */
1.351 djm 2521: ctx->nnew = ctx->nincomplete = 0;
2522: want = HKF_MATCH_HOST | ( options.check_host_ip ? HKF_MATCH_IP : 0);
1.269 djm 2523: for (i = 0; i < ctx->nkeys; i++) {
1.351 djm 2524: if (ctx->keys_match[i] == 0)
1.269 djm 2525: ctx->nnew++;
1.351 djm 2526: if ((ctx->keys_match[i] & want) != want)
2527: ctx->nincomplete++;
1.269 djm 2528: }
2529:
1.354 djm 2530: debug3_f("%zu server keys: %zu new, %zu retained, "
2531: "%zu incomplete match. %zu to remove", ctx->nkeys, ctx->nnew,
2532: ctx->nkeys - ctx->nnew - ctx->nincomplete,
1.351 djm 2533: ctx->nincomplete, ctx->nold);
1.269 djm 2534:
1.353 djm 2535: if (ctx->nnew == 0 && ctx->nold == 0) {
1.354 djm 2536: debug_f("no new or deprecated keys from server");
1.353 djm 2537: goto out;
2538: }
2539:
2540: /* Various reasons why we cannot proceed with the update */
2541: if (ctx->complex_hostspec) {
1.354 djm 2542: debug_f("CA/revocation marker, manual host list or wildcard "
2543: "host pattern found, skipping UserKnownHostsFile update");
1.353 djm 2544: goto out;
2545: }
2546: if (ctx->other_name_seen) {
1.354 djm 2547: debug_f("host key found matching a different name/address, "
2548: "skipping UserKnownHostsFile update");
1.347 djm 2549: goto out;
1.352 djm 2550: }
2551: /*
2552: * If removing keys, check whether they appear under different
2553: * names/addresses and refuse to proceed if they do. This avoids
2554: * cases such as hosts with multiple names becoming inconsistent
2555: * with regards to CheckHostIP entries.
2556: * XXX UpdateHostkeys=force to override this (and other) checks?
2557: */
2558: if (ctx->nold != 0) {
2559: if (check_old_keys_othernames(ctx) != 0)
2560: goto out; /* error already logged */
2561: if (ctx->old_key_seen) {
1.354 djm 2562: debug_f("key(s) for %s%s%s exist under other names; "
2563: "skipping UserKnownHostsFile update",
1.352 djm 2564: ctx->host_str, ctx->ip_str == NULL ? "" : ",",
2565: ctx->ip_str == NULL ? "" : ctx->ip_str);
2566: goto out;
2567: }
2568: }
2569:
1.353 djm 2570: if (ctx->nnew == 0) {
1.351 djm 2571: /*
2572: * We have some keys to remove or fix matching for.
2573: * We can proceed to do this without requiring a fresh proof
2574: * from the server.
2575: */
1.269 djm 2576: update_known_hosts(ctx);
1.353 djm 2577: goto out;
2578: }
2579: /*
2580: * We have received previously-unseen keys from the server.
2581: * Ask the server to confirm ownership of the private halves.
2582: */
1.354 djm 2583: debug3_f("asking server to prove ownership for %zu keys", ctx->nnew);
1.353 djm 2584: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
2585: (r = sshpkt_put_cstring(ssh,
2586: "hostkeys-prove-00@openssh.com")) != 0 ||
2587: (r = sshpkt_put_u8(ssh, 1)) != 0) /* bool: want reply */
1.354 djm 2588: fatal_fr(r, "prepare hostkeys-prove");
1.353 djm 2589: if ((buf = sshbuf_new()) == NULL)
1.354 djm 2590: fatal_f("sshbuf_new");
1.353 djm 2591: for (i = 0; i < ctx->nkeys; i++) {
2592: if (ctx->keys_match[i])
2593: continue;
2594: sshbuf_reset(buf);
2595: if ((r = sshkey_putb(ctx->keys[i], buf)) != 0 ||
1.354 djm 2596: (r = sshpkt_put_stringb(ssh, buf)) != 0)
2597: fatal_fr(r, "assemble hostkeys-prove");
1.269 djm 2598: }
1.353 djm 2599: if ((r = sshpkt_send(ssh)) != 0)
1.354 djm 2600: fatal_fr(r, "send hostkeys-prove");
1.353 djm 2601: client_register_global_confirm(
1.381 djm 2602: client_global_hostkeys_prove_confirm, ctx);
1.353 djm 2603: ctx = NULL; /* will be freed in callback */
1.384 djm 2604: prove_sent = 1;
1.269 djm 2605:
1.267 djm 2606: /* Success */
2607: out:
1.269 djm 2608: hostkeys_update_ctx_free(ctx);
1.267 djm 2609: sshkey_free(key);
2610: sshbuf_free(buf);
1.384 djm 2611: if (!prove_sent) {
2612: /* UpdateHostkeys handling completed */
2613: hostkeys_update_complete = 1;
2614: client_repledge();
2615: }
1.269 djm 2616: /*
2617: * NB. Return success for all cases. The server doesn't need to know
2618: * what the client does with its hosts file.
2619: */
2620: return 1;
1.267 djm 2621: }
2622:
1.264 markus 2623: static int
1.297 markus 2624: client_input_global_request(int type, u_int32_t seq, struct ssh *ssh)
1.95 markus 2625: {
2626: char *rtype;
1.320 djm 2627: u_char want_reply;
2628: int r, success = 0;
1.95 markus 2629:
1.320 djm 2630: if ((r = sshpkt_get_cstring(ssh, &rtype, NULL)) != 0 ||
2631: (r = sshpkt_get_u8(ssh, &want_reply)) != 0)
2632: goto out;
1.117 markus 2633: debug("client_input_global_request: rtype %s want_reply %d",
2634: rtype, want_reply);
1.270 djm 2635: if (strcmp(rtype, "hostkeys-00@openssh.com") == 0)
1.321 djm 2636: success = client_input_hostkeys(ssh);
1.95 markus 2637: if (want_reply) {
1.320 djm 2638: if ((r = sshpkt_start(ssh, success ? SSH2_MSG_REQUEST_SUCCESS :
2639: SSH2_MSG_REQUEST_FAILURE)) != 0 ||
2640: (r = sshpkt_send(ssh)) != 0 ||
2641: (r = ssh_packet_write_wait(ssh)) != 0)
2642: goto out;
1.95 markus 2643: }
1.320 djm 2644: r = 0;
2645: out:
1.250 djm 2646: free(rtype);
1.320 djm 2647: return r;
1.95 markus 2648: }
1.22 markus 2649:
1.354 djm 2650: static void
2651: client_send_env(struct ssh *ssh, int id, const char *name, const char *val)
2652: {
2653: int r;
2654:
2655: debug("channel %d: setting env %s = \"%s\"", id, name, val);
2656: channel_request_start(ssh, id, "env", 0);
2657: if ((r = sshpkt_put_cstring(ssh, name)) != 0 ||
2658: (r = sshpkt_put_cstring(ssh, val)) != 0 ||
2659: (r = sshpkt_send(ssh)) != 0)
2660: fatal_fr(r, "send setenv");
2661: }
2662:
1.123 djm 2663: void
1.303 djm 2664: client_session2_setup(struct ssh *ssh, int id, int want_tty, int want_subsystem,
1.315 markus 2665: const char *term, struct termios *tiop, int in_fd, struct sshbuf *cmd,
2666: char **env)
1.123 djm 2667: {
1.380 djm 2668: size_t i, j, len;
2669: int matched, r;
1.313 djm 2670: char *name, *val;
1.132 djm 2671: Channel *c = NULL;
1.123 djm 2672:
1.354 djm 2673: debug2_f("id %d", id);
1.123 djm 2674:
1.303 djm 2675: if ((c = channel_lookup(ssh, id)) == NULL)
1.354 djm 2676: fatal_f("channel %d: unknown channel", id);
1.224 djm 2677:
1.320 djm 2678: ssh_packet_set_interactive(ssh, want_tty,
1.224 djm 2679: options.ip_qos_interactive, options.ip_qos_bulk);
1.132 djm 2680:
1.123 djm 2681: if (want_tty) {
2682: struct winsize ws;
2683:
2684: /* Store window size in the packet. */
1.326 deraadt 2685: if (ioctl(in_fd, TIOCGWINSZ, &ws) == -1)
1.123 djm 2686: memset(&ws, 0, sizeof(ws));
2687:
1.303 djm 2688: channel_request_start(ssh, id, "pty-req", 1);
2689: client_expect_confirm(ssh, id, "PTY allocation", CONFIRM_TTY);
1.320 djm 2690: if ((r = sshpkt_put_cstring(ssh, term != NULL ? term : ""))
2691: != 0 ||
2692: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
2693: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
2694: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
2695: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0)
1.354 djm 2696: fatal_fr(r, "build pty-req");
1.194 djm 2697: if (tiop == NULL)
2698: tiop = get_saved_tio();
1.316 markus 2699: ssh_tty_make_modes(ssh, -1, tiop);
1.320 djm 2700: if ((r = sshpkt_send(ssh)) != 0)
1.354 djm 2701: fatal_fr(r, "send pty-req");
1.123 djm 2702: /* XXX wait for reply */
1.132 djm 2703: c->client_tty = 1;
1.123 djm 2704: }
2705:
2706: /* Transfer any environment variables from client to server */
1.126 djm 2707: if (options.num_send_env != 0 && env != NULL) {
1.123 djm 2708: debug("Sending environment.");
1.126 djm 2709: for (i = 0; env[i] != NULL; i++) {
1.123 djm 2710: /* Split */
1.126 djm 2711: name = xstrdup(env[i]);
1.123 djm 2712: if ((val = strchr(name, '=')) == NULL) {
1.250 djm 2713: free(name);
1.123 djm 2714: continue;
2715: }
2716: *val++ = '\0';
2717:
2718: matched = 0;
2719: for (j = 0; j < options.num_send_env; j++) {
2720: if (match_pattern(name, options.send_env[j])) {
2721: matched = 1;
2722: break;
2723: }
2724: }
2725: if (!matched) {
2726: debug3("Ignored env %s", name);
1.250 djm 2727: free(name);
1.123 djm 2728: continue;
2729: }
1.354 djm 2730: client_send_env(ssh, id, name, val);
1.250 djm 2731: free(name);
1.123 djm 2732: }
1.313 djm 2733: }
2734: for (i = 0; i < options.num_setenv; i++) {
2735: /* Split */
2736: name = xstrdup(options.setenv[i]);
2737: if ((val = strchr(name, '=')) == NULL) {
2738: free(name);
2739: continue;
2740: }
2741: *val++ = '\0';
1.354 djm 2742: client_send_env(ssh, id, name, val);
1.313 djm 2743: free(name);
1.123 djm 2744: }
2745:
1.315 markus 2746: len = sshbuf_len(cmd);
1.123 djm 2747: if (len > 0) {
2748: if (len > 900)
2749: len = 900;
2750: if (want_subsystem) {
1.190 djm 2751: debug("Sending subsystem: %.*s",
1.380 djm 2752: (int)len, (const u_char*)sshbuf_ptr(cmd));
1.303 djm 2753: channel_request_start(ssh, id, "subsystem", 1);
2754: client_expect_confirm(ssh, id, "subsystem",
2755: CONFIRM_CLOSE);
1.123 djm 2756: } else {
1.190 djm 2757: debug("Sending command: %.*s",
1.380 djm 2758: (int)len, (const u_char*)sshbuf_ptr(cmd));
1.303 djm 2759: channel_request_start(ssh, id, "exec", 1);
2760: client_expect_confirm(ssh, id, "exec", CONFIRM_CLOSE);
1.123 djm 2761: }
1.320 djm 2762: if ((r = sshpkt_put_stringb(ssh, cmd)) != 0 ||
2763: (r = sshpkt_send(ssh)) != 0)
1.354 djm 2764: fatal_fr(r, "send command");
1.123 djm 2765: } else {
1.303 djm 2766: channel_request_start(ssh, id, "shell", 1);
2767: client_expect_confirm(ssh, id, "shell", CONFIRM_CLOSE);
1.354 djm 2768: if ((r = sshpkt_send(ssh)) != 0)
2769: fatal_fr(r, "send shell");
1.123 djm 2770: }
1.384 djm 2771:
2772: session_setup_complete = 1;
2773: client_repledge();
1.123 djm 2774: }
2775:
1.77 itojun 2776: static void
1.321 djm 2777: client_init_dispatch(struct ssh *ssh)
1.16 markus 2778: {
1.321 djm 2779: ssh_dispatch_init(ssh, &dispatch_protocol_error);
1.100 markus 2780:
1.321 djm 2781: ssh_dispatch_set(ssh, SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
2782: ssh_dispatch_set(ssh, SSH2_MSG_CHANNEL_DATA, &channel_input_data);
2783: ssh_dispatch_set(ssh, SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
2784: ssh_dispatch_set(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
2785: ssh_dispatch_set(ssh, SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
2786: ssh_dispatch_set(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2787: ssh_dispatch_set(ssh, SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2788: ssh_dispatch_set(ssh, SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
2789: ssh_dispatch_set(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
2790: ssh_dispatch_set(ssh, SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
2791: ssh_dispatch_set(ssh, SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
2792: ssh_dispatch_set(ssh, SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1.55 markus 2793:
2794: /* rekeying */
1.321 djm 2795: ssh_dispatch_set(ssh, SSH2_MSG_KEXINIT, &kex_input_kexinit);
1.100 markus 2796:
2797: /* global request reply messages */
1.321 djm 2798: ssh_dispatch_set(ssh, SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
2799: ssh_dispatch_set(ssh, SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1.232 djm 2800: }
2801:
2802: void
2803: client_stop_mux(void)
2804: {
2805: if (options.control_path != NULL && muxserver_sock != -1)
2806: unlink(options.control_path);
2807: /*
1.247 dtucker 2808: * If we are in persist mode, or don't have a shell, signal that we
2809: * should close when all active channels are closed.
1.232 djm 2810: */
1.366 djm 2811: if (options.control_persist || options.session_type == SESSION_TYPE_NONE) {
1.232 djm 2812: session_closed = 1;
1.235 djm 2813: setproctitle("[stopped mux]");
2814: }
1.113 markus 2815: }
2816:
2817: /* client specific fatal cleanup */
2818: void
1.114 markus 2819: cleanup_exit(int i)
1.113 markus 2820: {
1.233 djm 2821: leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1.192 djm 2822: if (options.control_path != NULL && muxserver_sock != -1)
1.123 djm 2823: unlink(options.control_path);
1.223 djm 2824: ssh_kill_proxy_command();
1.114 markus 2825: _exit(i);
1.1 deraadt 2826: }
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