Annotation of src/usr.bin/ssh/channels.c, Revision 1.333
1.333 ! markus 1: /* $OpenBSD: channels.c,v 1.332 2014/04/28 03:09:18 djm Exp $ */
1.1 deraadt 2: /*
1.26 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
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.234 stevesk 43: #include <sys/ioctl.h>
1.235 stevesk 44: #include <sys/un.h>
1.251 stevesk 45: #include <sys/socket.h>
1.261 stevesk 46: #include <sys/time.h>
1.275 djm 47: #include <sys/queue.h>
1.251 stevesk 48:
49: #include <netinet/in.h>
50: #include <arpa/inet.h>
1.233 stevesk 51:
1.254 stevesk 52: #include <errno.h>
1.298 dtucker 53: #include <fcntl.h>
1.255 stevesk 54: #include <netdb.h>
1.263 stevesk 55: #include <stdio.h>
1.262 stevesk 56: #include <stdlib.h>
1.260 stevesk 57: #include <string.h>
1.233 stevesk 58: #include <termios.h>
1.256 stevesk 59: #include <unistd.h>
1.265 deraadt 60: #include <stdarg.h>
1.1 deraadt 61:
1.265 deraadt 62: #include "xmalloc.h"
1.1 deraadt 63: #include "ssh.h"
1.82 markus 64: #include "ssh1.h"
65: #include "ssh2.h"
1.1 deraadt 66: #include "packet.h"
1.82 markus 67: #include "log.h"
68: #include "misc.h"
1.265 deraadt 69: #include "buffer.h"
1.14 markus 70: #include "channels.h"
71: #include "compat.h"
1.82 markus 72: #include "canohost.h"
1.64 markus 73: #include "key.h"
74: #include "authfd.h"
1.147 stevesk 75: #include "pathnames.h"
1.1 deraadt 76:
1.121 markus 77: /* -- channel core */
1.12 markus 78:
1.27 markus 79: /*
80: * Pointer to an array containing all allocated channels. The array is
81: * dynamically extended as needed.
82: */
1.113 markus 83: static Channel **channels = NULL;
1.1 deraadt 84:
1.27 markus 85: /*
86: * Size of the channel array. All slots of the array must always be
1.113 markus 87: * initialized (at least the type field); unused slots set to NULL
1.27 markus 88: */
1.209 avsm 89: static u_int channels_alloc = 0;
1.1 deraadt 90:
1.27 markus 91: /*
92: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 93: * updated in channel_new.
1.27 markus 94: */
1.84 markus 95: static int channel_max_fd = 0;
1.1 deraadt 96:
97:
1.121 markus 98: /* -- tcp forwarding */
1.1 deraadt 99:
1.27 markus 100: /*
101: * Data structure for storing which hosts are permitted for forward requests.
102: * The local sides of any remote forwards are stored in this array to prevent
103: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
104: * network (which might be behind a firewall).
105: */
1.25 markus 106: typedef struct {
1.41 markus 107: char *host_to_connect; /* Connect to 'host'. */
108: u_short port_to_connect; /* Connect to 'port'. */
1.333 ! markus 109: char *listen_host; /* Remote side should listen address. */
! 110: u_short listen_port; /* Remote side should listen port. */
1.1 deraadt 111: } ForwardPermission;
112:
1.257 dtucker 113: /* List of all permitted host/port pairs to connect by the user. */
1.305 djm 114: static ForwardPermission *permitted_opens = NULL;
1.121 markus 115:
1.257 dtucker 116: /* List of all permitted host/port pairs to connect by the admin. */
1.305 djm 117: static ForwardPermission *permitted_adm_opens = NULL;
1.257 dtucker 118:
119: /* Number of permitted host/port pairs in the array permitted by the user. */
1.1 deraadt 120: static int num_permitted_opens = 0;
1.257 dtucker 121:
122: /* Number of permitted host/port pair in the array permitted by the admin. */
123: static int num_adm_permitted_opens = 0;
124:
1.314 dtucker 125: /* special-case port number meaning allow any port */
126: #define FWD_PERMIT_ANY_PORT 0
127:
1.27 markus 128: /*
129: * If this is true, all opens are permitted. This is the case on the server
130: * on which we have to trust the client anyway, and the user could do
131: * anything after logging in anyway.
132: */
1.1 deraadt 133: static int all_opens_permitted = 0;
134:
1.121 markus 135:
136: /* -- X11 forwarding */
137:
138: /* Maximum number of fake X11 displays to try. */
139: #define MAX_DISPLAYS 1000
140:
1.219 djm 141: /* Saved X11 local (client) display. */
142: static char *x11_saved_display = NULL;
143:
1.121 markus 144: /* Saved X11 authentication protocol name. */
145: static char *x11_saved_proto = NULL;
146:
147: /* Saved X11 authentication data. This is the real data. */
148: static char *x11_saved_data = NULL;
149: static u_int x11_saved_data_len = 0;
150:
151: /*
152: * Fake X11 authentication data. This is what the server will be sending us;
153: * we should replace any occurrences of this by the real data.
154: */
1.240 deraadt 155: static u_char *x11_fake_data = NULL;
1.121 markus 156: static u_int x11_fake_data_len;
157:
158:
159: /* -- agent forwarding */
160:
161: #define NUM_SOCKS 10
162:
1.82 markus 163: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 164: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 165:
1.121 markus 166: /* helper */
1.127 itojun 167: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 168:
1.276 djm 169: /* non-blocking connect helpers */
170: static int connect_next(struct channel_connect *);
171: static void channel_connect_ctx_free(struct channel_connect *);
172:
1.121 markus 173: /* -- channel core */
1.41 markus 174:
175: Channel *
1.229 markus 176: channel_by_id(int id)
1.41 markus 177: {
178: Channel *c;
1.113 markus 179:
1.209 avsm 180: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 181: logit("channel_by_id: %d: bad id", id);
1.41 markus 182: return NULL;
183: }
1.113 markus 184: c = channels[id];
185: if (c == NULL) {
1.229 markus 186: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 187: return NULL;
188: }
189: return c;
1.55 markus 190: }
191:
1.27 markus 192: /*
1.229 markus 193: * Returns the channel if it is allowed to receive protocol messages.
194: * Private channels, like listening sockets, may not receive messages.
195: */
196: Channel *
197: channel_lookup(int id)
198: {
199: Channel *c;
200:
201: if ((c = channel_by_id(id)) == NULL)
202: return (NULL);
203:
1.237 deraadt 204: switch (c->type) {
1.229 markus 205: case SSH_CHANNEL_X11_OPEN:
206: case SSH_CHANNEL_LARVAL:
207: case SSH_CHANNEL_CONNECTING:
208: case SSH_CHANNEL_DYNAMIC:
209: case SSH_CHANNEL_OPENING:
210: case SSH_CHANNEL_OPEN:
211: case SSH_CHANNEL_INPUT_DRAINING:
212: case SSH_CHANNEL_OUTPUT_DRAINING:
1.323 dtucker 213: case SSH_CHANNEL_ABANDONED:
1.229 markus 214: return (c);
215: }
216: logit("Non-public channel %d, type %d.", id, c->type);
217: return (NULL);
218: }
219:
220: /*
1.55 markus 221: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 222: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 223: */
1.127 itojun 224: static void
1.71 markus 225: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 226: int extusage, int nonblock, int is_tty)
1.1 deraadt 227: {
1.25 markus 228: /* Update the maximum file descriptor value. */
1.84 markus 229: channel_max_fd = MAX(channel_max_fd, rfd);
230: channel_max_fd = MAX(channel_max_fd, wfd);
231: channel_max_fd = MAX(channel_max_fd, efd);
232:
1.298 dtucker 233: if (rfd != -1)
234: fcntl(rfd, F_SETFD, FD_CLOEXEC);
235: if (wfd != -1 && wfd != rfd)
236: fcntl(wfd, F_SETFD, FD_CLOEXEC);
237: if (efd != -1 && efd != rfd && efd != wfd)
238: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 239:
1.52 markus 240: c->rfd = rfd;
241: c->wfd = wfd;
242: c->sock = (rfd == wfd) ? rfd : -1;
243: c->efd = efd;
244: c->extended_usage = extusage;
1.71 markus 245:
1.282 dtucker 246: if ((c->isatty = is_tty) != 0)
1.194 markus 247: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 248:
1.71 markus 249: /* enable nonblocking mode */
250: if (nonblock) {
251: if (rfd != -1)
252: set_nonblock(rfd);
253: if (wfd != -1)
254: set_nonblock(wfd);
255: if (efd != -1)
256: set_nonblock(efd);
257: }
1.52 markus 258: }
259:
260: /*
261: * Allocate a new channel object and set its type and socket. This will cause
262: * remote_name to be freed.
263: */
1.113 markus 264: Channel *
1.52 markus 265: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 266: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 267: {
1.209 avsm 268: int found;
269: u_int i;
1.52 markus 270: Channel *c;
1.25 markus 271:
272: /* Do initial allocation if this is the first call. */
273: if (channels_alloc == 0) {
274: channels_alloc = 10;
1.242 djm 275: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 276: for (i = 0; i < channels_alloc; i++)
1.113 markus 277: channels[i] = NULL;
1.25 markus 278: }
279: /* Try to find a free slot where to put the new channel. */
280: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 281: if (channels[i] == NULL) {
1.25 markus 282: /* Found a free slot. */
1.209 avsm 283: found = (int)i;
1.25 markus 284: break;
285: }
1.209 avsm 286: if (found < 0) {
1.27 markus 287: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 288: found = channels_alloc;
1.179 markus 289: if (channels_alloc > 10000)
290: fatal("channel_new: internal error: channels_alloc %d "
291: "too big.", channels_alloc);
1.243 djm 292: channels = xrealloc(channels, channels_alloc + 10,
293: sizeof(Channel *));
1.195 markus 294: channels_alloc += 10;
1.70 markus 295: debug2("channel: expanding %d", channels_alloc);
1.25 markus 296: for (i = found; i < channels_alloc; i++)
1.113 markus 297: channels[i] = NULL;
1.25 markus 298: }
1.113 markus 299: /* Initialize and return new channel. */
1.242 djm 300: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 301: buffer_init(&c->input);
302: buffer_init(&c->output);
1.41 markus 303: buffer_init(&c->extended);
1.293 djm 304: c->path = NULL;
1.312 djm 305: c->listening_addr = NULL;
306: c->listening_port = 0;
1.159 markus 307: c->ostate = CHAN_OUTPUT_OPEN;
308: c->istate = CHAN_INPUT_OPEN;
309: c->flags = 0;
1.281 djm 310: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0);
1.317 djm 311: c->notbefore = 0;
1.25 markus 312: c->self = found;
313: c->type = type;
1.41 markus 314: c->ctype = ctype;
1.51 markus 315: c->local_window = window;
316: c->local_window_max = window;
317: c->local_consumed = 0;
318: c->local_maxpacket = maxpack;
1.25 markus 319: c->remote_id = -1;
1.190 markus 320: c->remote_name = xstrdup(remote_name);
1.41 markus 321: c->remote_window = 0;
322: c->remote_maxpacket = 0;
1.133 markus 323: c->force_drain = 0;
1.149 markus 324: c->single_connection = 0;
1.131 markus 325: c->detach_user = NULL;
1.225 djm 326: c->detach_close = 0;
1.275 djm 327: c->open_confirm = NULL;
328: c->open_confirm_ctx = NULL;
1.65 markus 329: c->input_filter = NULL;
1.231 reyk 330: c->output_filter = NULL;
1.280 djm 331: c->filter_ctx = NULL;
332: c->filter_cleanup = NULL;
1.302 djm 333: c->ctl_chan = -1;
334: c->mux_rcb = NULL;
335: c->mux_ctx = NULL;
1.304 djm 336: c->mux_pause = 0;
1.299 markus 337: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 338: TAILQ_INIT(&c->status_confirms);
1.25 markus 339: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 340: return c;
1.1 deraadt 341: }
1.52 markus 342:
1.132 markus 343: static int
344: channel_find_maxfd(void)
345: {
1.209 avsm 346: u_int i;
347: int max = 0;
1.132 markus 348: Channel *c;
349:
350: for (i = 0; i < channels_alloc; i++) {
351: c = channels[i];
352: if (c != NULL) {
353: max = MAX(max, c->rfd);
354: max = MAX(max, c->wfd);
355: max = MAX(max, c->efd);
356: }
357: }
358: return max;
359: }
360:
361: int
362: channel_close_fd(int *fdp)
363: {
364: int ret = 0, fd = *fdp;
365:
366: if (fd != -1) {
367: ret = close(fd);
368: *fdp = -1;
369: if (fd == channel_max_fd)
370: channel_max_fd = channel_find_maxfd();
371: }
372: return ret;
373: }
374:
1.52 markus 375: /* Close all channel fd/socket. */
1.127 itojun 376: static void
1.52 markus 377: channel_close_fds(Channel *c)
378: {
1.132 markus 379: channel_close_fd(&c->sock);
380: channel_close_fd(&c->rfd);
381: channel_close_fd(&c->wfd);
382: channel_close_fd(&c->efd);
1.121 markus 383: }
384:
385: /* Free the channel and close its fd/socket. */
386: void
387: channel_free(Channel *c)
388: {
389: char *s;
1.209 avsm 390: u_int i, n;
1.275 djm 391: struct channel_confirm *cc;
1.121 markus 392:
393: for (n = 0, i = 0; i < channels_alloc; i++)
394: if (channels[i])
395: n++;
1.209 avsm 396: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 397: c->remote_name ? c->remote_name : "???", n);
398:
399: s = channel_open_message();
1.194 markus 400: debug3("channel %d: status: %s", c->self, s);
1.321 djm 401: free(s);
1.121 markus 402:
403: if (c->sock != -1)
404: shutdown(c->sock, SHUT_RDWR);
405: channel_close_fds(c);
406: buffer_free(&c->input);
407: buffer_free(&c->output);
408: buffer_free(&c->extended);
1.321 djm 409: free(c->remote_name);
410: c->remote_name = NULL;
411: free(c->path);
412: c->path = NULL;
413: free(c->listening_addr);
414: c->listening_addr = NULL;
1.275 djm 415: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
416: if (cc->abandon_cb != NULL)
417: cc->abandon_cb(c, cc->ctx);
418: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 419: explicit_bzero(cc, sizeof(*cc));
1.321 djm 420: free(cc);
1.275 djm 421: }
1.280 djm 422: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
423: c->filter_cleanup(c->self, c->filter_ctx);
1.121 markus 424: channels[c->self] = NULL;
1.321 djm 425: free(c);
1.121 markus 426: }
427:
428: void
1.126 markus 429: channel_free_all(void)
1.121 markus 430: {
1.209 avsm 431: u_int i;
1.121 markus 432:
1.126 markus 433: for (i = 0; i < channels_alloc; i++)
434: if (channels[i] != NULL)
435: channel_free(channels[i]);
1.131 markus 436: }
437:
1.121 markus 438: /*
439: * Closes the sockets/fds of all channels. This is used to close extra file
440: * descriptors after a fork.
441: */
442: void
1.142 itojun 443: channel_close_all(void)
1.121 markus 444: {
1.209 avsm 445: u_int i;
1.121 markus 446:
447: for (i = 0; i < channels_alloc; i++)
448: if (channels[i] != NULL)
449: channel_close_fds(channels[i]);
450: }
451:
452: /*
1.131 markus 453: * Stop listening to channels.
454: */
455: void
456: channel_stop_listening(void)
457: {
1.209 avsm 458: u_int i;
1.131 markus 459: Channel *c;
460:
461: for (i = 0; i < channels_alloc; i++) {
462: c = channels[i];
463: if (c != NULL) {
464: switch (c->type) {
465: case SSH_CHANNEL_AUTH_SOCKET:
466: case SSH_CHANNEL_PORT_LISTENER:
467: case SSH_CHANNEL_RPORT_LISTENER:
468: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 469: channel_close_fd(&c->sock);
1.131 markus 470: channel_free(c);
471: break;
472: }
473: }
474: }
475: }
476:
477: /*
1.121 markus 478: * Returns true if no channel has too much buffered data, and false if one or
479: * more channel is overfull.
480: */
481: int
1.142 itojun 482: channel_not_very_much_buffered_data(void)
1.121 markus 483: {
484: u_int i;
485: Channel *c;
486:
487: for (i = 0; i < channels_alloc; i++) {
488: c = channels[i];
489: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 490: #if 0
491: if (!compat20 &&
492: buffer_len(&c->input) > packet_get_maxsize()) {
1.185 markus 493: debug2("channel %d: big input buffer %d",
1.121 markus 494: c->self, buffer_len(&c->input));
495: return 0;
496: }
1.136 markus 497: #endif
1.121 markus 498: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 499: debug2("channel %d: big output buffer %u > %u",
1.136 markus 500: c->self, buffer_len(&c->output),
501: packet_get_maxsize());
1.121 markus 502: return 0;
503: }
504: }
505: }
506: return 1;
507: }
508:
509: /* Returns true if any channel is still open. */
510: int
1.142 itojun 511: channel_still_open(void)
1.121 markus 512: {
1.209 avsm 513: u_int i;
1.121 markus 514: Channel *c;
515:
516: for (i = 0; i < channels_alloc; i++) {
517: c = channels[i];
518: if (c == NULL)
519: continue;
520: switch (c->type) {
521: case SSH_CHANNEL_X11_LISTENER:
522: case SSH_CHANNEL_PORT_LISTENER:
523: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 524: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 525: case SSH_CHANNEL_CLOSED:
526: case SSH_CHANNEL_AUTH_SOCKET:
527: case SSH_CHANNEL_DYNAMIC:
528: case SSH_CHANNEL_CONNECTING:
529: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 530: case SSH_CHANNEL_ABANDONED:
1.121 markus 531: continue;
532: case SSH_CHANNEL_LARVAL:
533: if (!compat20)
534: fatal("cannot happen: SSH_CHANNEL_LARVAL");
535: continue;
536: case SSH_CHANNEL_OPENING:
537: case SSH_CHANNEL_OPEN:
538: case SSH_CHANNEL_X11_OPEN:
1.302 djm 539: case SSH_CHANNEL_MUX_CLIENT:
1.121 markus 540: return 1;
541: case SSH_CHANNEL_INPUT_DRAINING:
542: case SSH_CHANNEL_OUTPUT_DRAINING:
543: if (!compat13)
544: fatal("cannot happen: OUT_DRAIN");
545: return 1;
546: default:
547: fatal("channel_still_open: bad channel type %d", c->type);
548: /* NOTREACHED */
549: }
550: }
551: return 0;
552: }
553:
554: /* Returns the id of an open channel suitable for keepaliving */
555: int
1.142 itojun 556: channel_find_open(void)
1.121 markus 557: {
1.209 avsm 558: u_int i;
1.121 markus 559: Channel *c;
560:
561: for (i = 0; i < channels_alloc; i++) {
562: c = channels[i];
1.206 djm 563: if (c == NULL || c->remote_id < 0)
1.121 markus 564: continue;
565: switch (c->type) {
566: case SSH_CHANNEL_CLOSED:
567: case SSH_CHANNEL_DYNAMIC:
568: case SSH_CHANNEL_X11_LISTENER:
569: case SSH_CHANNEL_PORT_LISTENER:
570: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 571: case SSH_CHANNEL_MUX_LISTENER:
572: case SSH_CHANNEL_MUX_CLIENT:
1.121 markus 573: case SSH_CHANNEL_OPENING:
574: case SSH_CHANNEL_CONNECTING:
575: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 576: case SSH_CHANNEL_ABANDONED:
1.121 markus 577: continue;
578: case SSH_CHANNEL_LARVAL:
579: case SSH_CHANNEL_AUTH_SOCKET:
580: case SSH_CHANNEL_OPEN:
581: case SSH_CHANNEL_X11_OPEN:
582: return i;
583: case SSH_CHANNEL_INPUT_DRAINING:
584: case SSH_CHANNEL_OUTPUT_DRAINING:
585: if (!compat13)
586: fatal("cannot happen: OUT_DRAIN");
587: return i;
588: default:
589: fatal("channel_find_open: bad channel type %d", c->type);
590: /* NOTREACHED */
591: }
592: }
593: return -1;
594: }
595:
596:
597: /*
598: * Returns a message describing the currently open forwarded connections,
599: * suitable for sending to the client. The message contains crlf pairs for
600: * newlines.
601: */
602: char *
1.142 itojun 603: channel_open_message(void)
1.121 markus 604: {
605: Buffer buffer;
606: Channel *c;
607: char buf[1024], *cp;
1.209 avsm 608: u_int i;
1.121 markus 609:
610: buffer_init(&buffer);
611: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
612: buffer_append(&buffer, buf, strlen(buf));
613: for (i = 0; i < channels_alloc; i++) {
614: c = channels[i];
615: if (c == NULL)
616: continue;
617: switch (c->type) {
618: case SSH_CHANNEL_X11_LISTENER:
619: case SSH_CHANNEL_PORT_LISTENER:
620: case SSH_CHANNEL_RPORT_LISTENER:
621: case SSH_CHANNEL_CLOSED:
622: case SSH_CHANNEL_AUTH_SOCKET:
623: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 624: case SSH_CHANNEL_ABANDONED:
1.302 djm 625: case SSH_CHANNEL_MUX_CLIENT:
626: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 627: continue;
628: case SSH_CHANNEL_LARVAL:
629: case SSH_CHANNEL_OPENING:
630: case SSH_CHANNEL_CONNECTING:
631: case SSH_CHANNEL_DYNAMIC:
632: case SSH_CHANNEL_OPEN:
633: case SSH_CHANNEL_X11_OPEN:
634: case SSH_CHANNEL_INPUT_DRAINING:
635: case SSH_CHANNEL_OUTPUT_DRAINING:
1.204 djm 636: snprintf(buf, sizeof buf,
1.302 djm 637: " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cc %d)\r\n",
1.121 markus 638: c->self, c->remote_name,
639: c->type, c->remote_id,
640: c->istate, buffer_len(&c->input),
641: c->ostate, buffer_len(&c->output),
1.302 djm 642: c->rfd, c->wfd, c->ctl_chan);
1.121 markus 643: buffer_append(&buffer, buf, strlen(buf));
644: continue;
645: default:
646: fatal("channel_open_message: bad channel type %d", c->type);
647: /* NOTREACHED */
648: }
649: }
650: buffer_append(&buffer, "\0", 1);
651: cp = xstrdup(buffer_ptr(&buffer));
652: buffer_free(&buffer);
653: return cp;
654: }
655:
656: void
657: channel_send_open(int id)
658: {
659: Channel *c = channel_lookup(id);
1.180 deraadt 660:
1.121 markus 661: if (c == NULL) {
1.188 itojun 662: logit("channel_send_open: %d: bad id", id);
1.121 markus 663: return;
664: }
1.184 markus 665: debug2("channel %d: send open", id);
1.121 markus 666: packet_start(SSH2_MSG_CHANNEL_OPEN);
667: packet_put_cstring(c->ctype);
668: packet_put_int(c->self);
669: packet_put_int(c->local_window);
670: packet_put_int(c->local_maxpacket);
671: packet_send();
672: }
673:
674: void
1.184 markus 675: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 676: {
1.184 markus 677: Channel *c = channel_lookup(id);
1.180 deraadt 678:
1.121 markus 679: if (c == NULL) {
1.188 itojun 680: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 681: return;
682: }
1.204 djm 683: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 684: packet_start(SSH2_MSG_CHANNEL_REQUEST);
685: packet_put_int(c->remote_id);
686: packet_put_cstring(service);
687: packet_put_char(wantconfirm);
688: }
1.241 deraadt 689:
1.121 markus 690: void
1.275 djm 691: channel_register_status_confirm(int id, channel_confirm_cb *cb,
692: channel_confirm_abandon_cb *abandon_cb, void *ctx)
693: {
694: struct channel_confirm *cc;
695: Channel *c;
696:
697: if ((c = channel_lookup(id)) == NULL)
698: fatal("channel_register_expect: %d: bad id", id);
699:
1.327 djm 700: cc = xcalloc(1, sizeof(*cc));
1.275 djm 701: cc->cb = cb;
702: cc->abandon_cb = abandon_cb;
703: cc->ctx = ctx;
704: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
705: }
706:
707: void
1.304 djm 708: channel_register_open_confirm(int id, channel_open_fn *fn, void *ctx)
1.121 markus 709: {
710: Channel *c = channel_lookup(id);
1.180 deraadt 711:
1.121 markus 712: if (c == NULL) {
1.287 stevesk 713: logit("channel_register_open_confirm: %d: bad id", id);
1.121 markus 714: return;
715: }
1.275 djm 716: c->open_confirm = fn;
717: c->open_confirm_ctx = ctx;
1.121 markus 718: }
1.241 deraadt 719:
1.121 markus 720: void
1.225 djm 721: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 722: {
1.229 markus 723: Channel *c = channel_by_id(id);
1.180 deraadt 724:
1.121 markus 725: if (c == NULL) {
1.188 itojun 726: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 727: return;
728: }
1.131 markus 729: c->detach_user = fn;
1.225 djm 730: c->detach_close = do_close;
1.121 markus 731: }
1.241 deraadt 732:
1.121 markus 733: void
734: channel_cancel_cleanup(int id)
735: {
1.229 markus 736: Channel *c = channel_by_id(id);
1.180 deraadt 737:
1.121 markus 738: if (c == NULL) {
1.188 itojun 739: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 740: return;
1.52 markus 741: }
1.131 markus 742: c->detach_user = NULL;
1.225 djm 743: c->detach_close = 0;
1.121 markus 744: }
1.241 deraadt 745:
1.121 markus 746: void
1.231 reyk 747: channel_register_filter(int id, channel_infilter_fn *ifn,
1.280 djm 748: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 749: {
750: Channel *c = channel_lookup(id);
1.180 deraadt 751:
1.121 markus 752: if (c == NULL) {
1.188 itojun 753: logit("channel_register_filter: %d: bad id", id);
1.121 markus 754: return;
1.52 markus 755: }
1.231 reyk 756: c->input_filter = ifn;
757: c->output_filter = ofn;
1.279 djm 758: c->filter_ctx = ctx;
1.280 djm 759: c->filter_cleanup = cfn;
1.52 markus 760: }
761:
1.49 markus 762: void
1.121 markus 763: channel_set_fds(int id, int rfd, int wfd, int efd,
1.282 dtucker 764: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 765: {
1.121 markus 766: Channel *c = channel_lookup(id);
1.180 deraadt 767:
1.121 markus 768: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
769: fatal("channel_activate for non-larval channel %d.", id);
1.282 dtucker 770: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 771: c->type = SSH_CHANNEL_OPEN;
1.168 markus 772: c->local_window = c->local_window_max = window_max;
1.121 markus 773: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
774: packet_put_int(c->remote_id);
775: packet_put_int(c->local_window);
776: packet_send();
1.1 deraadt 777: }
778:
1.27 markus 779: /*
1.41 markus 780: * 'channel_pre*' are called just before select() to add any bits relevant to
781: * channels in the select bitmasks.
782: */
783: /*
784: * 'channel_post*': perform any appropriate operations for channels which
785: * have events pending.
1.27 markus 786: */
1.237 deraadt 787: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 788: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
789: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
790:
1.259 stevesk 791: /* ARGSUSED */
1.127 itojun 792: static void
1.237 deraadt 793: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 794: {
795: FD_SET(c->sock, readset);
796: }
797:
1.259 stevesk 798: /* ARGSUSED */
1.127 itojun 799: static void
1.237 deraadt 800: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 801: {
802: debug3("channel %d: waiting for connection", c->self);
803: FD_SET(c->sock, writeset);
804: }
805:
1.127 itojun 806: static void
1.237 deraadt 807: channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 808: {
809: if (buffer_len(&c->input) < packet_get_maxsize())
810: FD_SET(c->sock, readset);
811: if (buffer_len(&c->output) > 0)
812: FD_SET(c->sock, writeset);
813: }
1.1 deraadt 814:
1.127 itojun 815: static void
1.237 deraadt 816: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 817: {
1.157 markus 818: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 819:
1.44 markus 820: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 821: limit > 0 &&
1.250 djm 822: buffer_len(&c->input) < limit &&
823: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 824: FD_SET(c->rfd, readset);
825: if (c->ostate == CHAN_OUTPUT_OPEN ||
826: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
827: if (buffer_len(&c->output) > 0) {
828: FD_SET(c->wfd, writeset);
829: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 830: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 831: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
832: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 833: else
834: chan_obuf_empty(c);
1.44 markus 835: }
836: }
837: /** XXX check close conditions, too */
1.277 markus 838: if (compat20 && c->efd != -1 &&
839: !(c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 840: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
841: buffer_len(&c->extended) > 0)
842: FD_SET(c->efd, writeset);
1.306 djm 843: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
844: (c->extended_usage == CHAN_EXTENDED_READ ||
845: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 846: buffer_len(&c->extended) < c->remote_window)
847: FD_SET(c->efd, readset);
848: }
1.204 djm 849: /* XXX: What about efd? races? */
1.44 markus 850: }
851:
1.259 stevesk 852: /* ARGSUSED */
1.127 itojun 853: static void
1.237 deraadt 854: channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 855: {
856: if (buffer_len(&c->input) == 0) {
857: packet_start(SSH_MSG_CHANNEL_CLOSE);
858: packet_put_int(c->remote_id);
859: packet_send();
860: c->type = SSH_CHANNEL_CLOSED;
1.194 markus 861: debug2("channel %d: closing after input drain.", c->self);
1.41 markus 862: }
863: }
864:
1.259 stevesk 865: /* ARGSUSED */
1.127 itojun 866: static void
1.237 deraadt 867: channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 868: {
869: if (buffer_len(&c->output) == 0)
1.113 markus 870: chan_mark_dead(c);
1.49 markus 871: else
1.41 markus 872: FD_SET(c->sock, writeset);
873: }
874:
875: /*
876: * This is a special state for X11 authentication spoofing. An opened X11
877: * connection (when authentication spoofing is being done) remains in this
878: * state until the first packet has been completely read. The authentication
879: * data in that packet is then substituted by the real data if it matches the
880: * fake data, and the channel is put into normal mode.
1.51 markus 881: * XXX All this happens at the client side.
1.121 markus 882: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 883: */
1.127 itojun 884: static int
1.121 markus 885: x11_open_helper(Buffer *b)
1.1 deraadt 886: {
1.77 markus 887: u_char *ucp;
888: u_int proto_len, data_len;
1.25 markus 889:
1.41 markus 890: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 891: if (buffer_len(b) < 12)
1.41 markus 892: return 0;
893:
894: /* Parse the lengths of variable-length fields. */
1.155 stevesk 895: ucp = buffer_ptr(b);
1.41 markus 896: if (ucp[0] == 0x42) { /* Byte order MSB first. */
897: proto_len = 256 * ucp[6] + ucp[7];
898: data_len = 256 * ucp[8] + ucp[9];
899: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
900: proto_len = ucp[6] + 256 * ucp[7];
901: data_len = ucp[8] + 256 * ucp[9];
902: } else {
1.194 markus 903: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 904: ucp[0]);
1.41 markus 905: return -1;
906: }
907:
908: /* Check if the whole packet is in buffer. */
1.121 markus 909: if (buffer_len(b) <
1.41 markus 910: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
911: return 0;
912:
913: /* Check if authentication protocol matches. */
914: if (proto_len != strlen(x11_saved_proto) ||
915: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 916: debug2("X11 connection uses different authentication protocol.");
1.41 markus 917: return -1;
918: }
919: /* Check if authentication data matches our fake data. */
920: if (data_len != x11_fake_data_len ||
1.308 djm 921: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.41 markus 922: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 923: debug2("X11 auth data does not match fake data.");
1.41 markus 924: return -1;
925: }
926: /* Check fake data length */
927: if (x11_fake_data_len != x11_saved_data_len) {
928: error("X11 fake_data_len %d != saved_data_len %d",
929: x11_fake_data_len, x11_saved_data_len);
930: return -1;
931: }
932: /*
933: * Received authentication protocol and data match
934: * our fake data. Substitute the fake data with real
935: * data.
936: */
937: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
938: x11_saved_data, x11_saved_data_len);
939: return 1;
940: }
941:
1.127 itojun 942: static void
1.237 deraadt 943: channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 944: {
1.121 markus 945: int ret = x11_open_helper(&c->output);
1.180 deraadt 946:
1.41 markus 947: if (ret == 1) {
948: /* Start normal processing for the channel. */
949: c->type = SSH_CHANNEL_OPEN;
1.47 markus 950: channel_pre_open_13(c, readset, writeset);
1.41 markus 951: } else if (ret == -1) {
952: /*
953: * We have received an X11 connection that has bad
954: * authentication information.
955: */
1.188 itojun 956: logit("X11 connection rejected because of wrong authentication.");
1.41 markus 957: buffer_clear(&c->input);
958: buffer_clear(&c->output);
1.132 markus 959: channel_close_fd(&c->sock);
1.41 markus 960: c->sock = -1;
961: c->type = SSH_CHANNEL_CLOSED;
962: packet_start(SSH_MSG_CHANNEL_CLOSE);
963: packet_put_int(c->remote_id);
964: packet_send();
965: }
966: }
1.25 markus 967:
1.127 itojun 968: static void
1.237 deraadt 969: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 970: {
1.121 markus 971: int ret = x11_open_helper(&c->output);
1.133 markus 972:
973: /* c->force_drain = 1; */
974:
1.41 markus 975: if (ret == 1) {
976: c->type = SSH_CHANNEL_OPEN;
1.157 markus 977: channel_pre_open(c, readset, writeset);
1.41 markus 978: } else if (ret == -1) {
1.188 itojun 979: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 980: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 981: chan_read_failed(c);
982: buffer_clear(&c->input);
983: chan_ibuf_empty(c);
984: buffer_clear(&c->output);
985: /* for proto v1, the peer will send an IEOF */
986: if (compat20)
987: chan_write_failed(c);
988: else
989: c->type = SSH_CHANNEL_OPEN;
1.194 markus 990: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 991: }
992: }
1.25 markus 993:
1.302 djm 994: static void
995: channel_pre_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
996: {
1.304 djm 997: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.302 djm 998: buffer_check_alloc(&c->input, CHAN_RBUF))
999: FD_SET(c->rfd, readset);
1000: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1001: /* clear buffer immediately (discard any partial packet) */
1002: buffer_clear(&c->input);
1003: chan_ibuf_empty(c);
1004: /* Start output drain. XXX just kill chan? */
1005: chan_rcvd_oclose(c);
1006: }
1007: if (c->ostate == CHAN_OUTPUT_OPEN ||
1008: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1009: if (buffer_len(&c->output) > 0)
1010: FD_SET(c->wfd, writeset);
1011: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1012: chan_obuf_empty(c);
1013: }
1014: }
1015:
1.104 markus 1016: /* try to decode a socks4 header */
1.259 stevesk 1017: /* ARGSUSED */
1.127 itojun 1018: static int
1.237 deraadt 1019: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 1020: {
1.181 markus 1021: char *p, *host;
1.292 djm 1022: u_int len, have, i, found, need;
1.148 deraadt 1023: char username[256];
1.103 markus 1024: struct {
1025: u_int8_t version;
1026: u_int8_t command;
1027: u_int16_t dest_port;
1.104 markus 1028: struct in_addr dest_addr;
1.103 markus 1029: } s4_req, s4_rsp;
1030:
1.104 markus 1031: debug2("channel %d: decode socks4", c->self);
1.109 markus 1032:
1033: have = buffer_len(&c->input);
1034: len = sizeof(s4_req);
1035: if (have < len)
1036: return 0;
1037: p = buffer_ptr(&c->input);
1.292 djm 1038:
1039: need = 1;
1040: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1041: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1042: debug2("channel %d: socks4a request", c->self);
1043: /* ... and needs an extra string (the hostname) */
1044: need = 2;
1045: }
1046: /* Check for terminating NUL on the string(s) */
1.109 markus 1047: for (found = 0, i = len; i < have; i++) {
1048: if (p[i] == '\0') {
1.292 djm 1049: found++;
1050: if (found == need)
1051: break;
1.109 markus 1052: }
1053: if (i > 1024) {
1054: /* the peer is probably sending garbage */
1055: debug("channel %d: decode socks4: too long",
1056: c->self);
1057: return -1;
1058: }
1059: }
1.292 djm 1060: if (found < need)
1.109 markus 1061: return 0;
1.103 markus 1062: buffer_get(&c->input, (char *)&s4_req.version, 1);
1063: buffer_get(&c->input, (char *)&s4_req.command, 1);
1064: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 1065: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 1066: have = buffer_len(&c->input);
1.103 markus 1067: p = buffer_ptr(&c->input);
1.331 djm 1068: if (memchr(p, '\0', have) == NULL)
1069: fatal("channel %d: decode socks4: user not nul terminated",
1070: c->self);
1.103 markus 1071: len = strlen(p);
1.106 markus 1072: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.292 djm 1073: len++; /* trailing '\0' */
1.103 markus 1074: if (len > have)
1.104 markus 1075: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 1076: c->self, len, have);
1077: strlcpy(username, p, sizeof(username));
1078: buffer_consume(&c->input, len);
1079:
1.321 djm 1080: free(c->path);
1081: c->path = NULL;
1.292 djm 1082: if (need == 1) { /* SOCKS4: one string */
1083: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1084: c->path = xstrdup(host);
1.292 djm 1085: } else { /* SOCKS4A: two strings */
1086: have = buffer_len(&c->input);
1087: p = buffer_ptr(&c->input);
1088: len = strlen(p);
1089: debug2("channel %d: decode socks4a: host %s/%d",
1090: c->self, p, len);
1091: len++; /* trailing '\0' */
1092: if (len > have)
1093: fatal("channel %d: decode socks4a: len %d > have %d",
1094: c->self, len, have);
1.293 djm 1095: if (len > NI_MAXHOST) {
1.292 djm 1096: error("channel %d: hostname \"%.100s\" too long",
1097: c->self, p);
1098: return -1;
1099: }
1.293 djm 1100: c->path = xstrdup(p);
1.292 djm 1101: buffer_consume(&c->input, len);
1102: }
1.103 markus 1103: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1104:
1.194 markus 1105: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1106: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1107:
1.104 markus 1108: if (s4_req.command != 1) {
1.292 djm 1109: debug("channel %d: cannot handle: %s cn %d",
1110: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1111: return -1;
1.103 markus 1112: }
1.104 markus 1113: s4_rsp.version = 0; /* vn: 0 for reply */
1114: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1115: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1116: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1117: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1118: return 1;
1119: }
1120:
1.193 markus 1121: /* try to decode a socks5 header */
1122: #define SSH_SOCKS5_AUTHDONE 0x1000
1123: #define SSH_SOCKS5_NOAUTH 0x00
1124: #define SSH_SOCKS5_IPV4 0x01
1125: #define SSH_SOCKS5_DOMAIN 0x03
1126: #define SSH_SOCKS5_IPV6 0x04
1127: #define SSH_SOCKS5_CONNECT 0x01
1128: #define SSH_SOCKS5_SUCCESS 0x00
1129:
1.259 stevesk 1130: /* ARGSUSED */
1.193 markus 1131: static int
1.237 deraadt 1132: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1133: {
1134: struct {
1135: u_int8_t version;
1136: u_int8_t command;
1137: u_int8_t reserved;
1138: u_int8_t atyp;
1139: } s5_req, s5_rsp;
1140: u_int16_t dest_port;
1.324 djm 1141: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1142: u_char *p;
1.252 djm 1143: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1144:
1145: debug2("channel %d: decode socks5", c->self);
1146: p = buffer_ptr(&c->input);
1147: if (p[0] != 0x05)
1148: return -1;
1149: have = buffer_len(&c->input);
1150: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1151: /* format: ver | nmethods | methods */
1.198 djm 1152: if (have < 2)
1.193 markus 1153: return 0;
1154: nmethods = p[1];
1155: if (have < nmethods + 2)
1156: return 0;
1157: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1158: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1159: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1160: found = 1;
1161: break;
1162: }
1163: }
1164: if (!found) {
1165: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1166: c->self);
1167: return -1;
1168: }
1169: buffer_consume(&c->input, nmethods + 2);
1170: buffer_put_char(&c->output, 0x05); /* version */
1171: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1172: FD_SET(c->sock, writeset);
1173: c->flags |= SSH_SOCKS5_AUTHDONE;
1174: debug2("channel %d: socks5 auth done", c->self);
1175: return 0; /* need more */
1176: }
1177: debug2("channel %d: socks5 post auth", c->self);
1178: if (have < sizeof(s5_req)+1)
1179: return 0; /* need more */
1.247 deraadt 1180: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1181: if (s5_req.version != 0x05 ||
1182: s5_req.command != SSH_SOCKS5_CONNECT ||
1183: s5_req.reserved != 0x00) {
1.194 markus 1184: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1185: return -1;
1186: }
1.213 deraadt 1187: switch (s5_req.atyp){
1.193 markus 1188: case SSH_SOCKS5_IPV4:
1189: addrlen = 4;
1190: af = AF_INET;
1191: break;
1192: case SSH_SOCKS5_DOMAIN:
1193: addrlen = p[sizeof(s5_req)];
1194: af = -1;
1195: break;
1196: case SSH_SOCKS5_IPV6:
1197: addrlen = 16;
1198: af = AF_INET6;
1199: break;
1200: default:
1.194 markus 1201: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1202: return -1;
1203: }
1.252 djm 1204: need = sizeof(s5_req) + addrlen + 2;
1205: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1206: need++;
1207: if (have < need)
1.193 markus 1208: return 0;
1209: buffer_consume(&c->input, sizeof(s5_req));
1210: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1211: buffer_consume(&c->input, 1); /* host string length */
1.324 djm 1212: buffer_get(&c->input, &dest_addr, addrlen);
1.193 markus 1213: buffer_get(&c->input, (char *)&dest_port, 2);
1214: dest_addr[addrlen] = '\0';
1.321 djm 1215: free(c->path);
1216: c->path = NULL;
1.293 djm 1217: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1218: if (addrlen >= NI_MAXHOST) {
1.293 djm 1219: error("channel %d: dynamic request: socks5 hostname "
1220: "\"%.100s\" too long", c->self, dest_addr);
1221: return -1;
1222: }
1223: c->path = xstrdup(dest_addr);
1224: } else {
1225: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1226: return -1;
1227: c->path = xstrdup(ntop);
1228: }
1.193 markus 1229: c->host_port = ntohs(dest_port);
1.198 djm 1230:
1.194 markus 1231: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1232: c->self, c->path, c->host_port, s5_req.command);
1233:
1234: s5_rsp.version = 0x05;
1235: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1236: s5_rsp.reserved = 0; /* ignored */
1237: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1238: dest_port = 0; /* ignored */
1239:
1.246 deraadt 1240: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1.325 djm 1241: buffer_put_int(&c->output, ntohl(INADDR_ANY)); /* bind address */
1.246 deraadt 1242: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1243: return 1;
1.301 dtucker 1244: }
1245:
1246: Channel *
1.302 djm 1247: channel_connect_stdio_fwd(const char *host_to_connect, u_short port_to_connect,
1248: int in, int out)
1.301 dtucker 1249: {
1250: Channel *c;
1251:
1252: debug("channel_connect_stdio_fwd %s:%d", host_to_connect,
1253: port_to_connect);
1254:
1255: c = channel_new("stdio-forward", SSH_CHANNEL_OPENING, in, out,
1256: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1257: 0, "stdio-forward", /*nonblock*/0);
1258:
1259: c->path = xstrdup(host_to_connect);
1260: c->host_port = port_to_connect;
1261: c->listening_port = 0;
1262: c->force_drain = 1;
1263:
1264: channel_register_fds(c, in, out, -1, 0, 1, 0);
1265: port_open_helper(c, "direct-tcpip");
1266:
1267: return c;
1.193 markus 1268: }
1269:
1.104 markus 1270: /* dynamic port forwarding */
1.127 itojun 1271: static void
1.237 deraadt 1272: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1273: {
1274: u_char *p;
1.217 djm 1275: u_int have;
1276: int ret;
1.103 markus 1277:
1.104 markus 1278: have = buffer_len(&c->input);
1279: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1280: /* buffer_dump(&c->input); */
1.104 markus 1281: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1282: if (have < 3) {
1.104 markus 1283: /* need more */
1284: FD_SET(c->sock, readset);
1285: return;
1286: }
1287: /* try to guess the protocol */
1288: p = buffer_ptr(&c->input);
1289: switch (p[0]) {
1290: case 0x04:
1291: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1292: break;
1293: case 0x05:
1294: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1295: break;
1296: default:
1297: ret = -1;
1298: break;
1299: }
1300: if (ret < 0) {
1.113 markus 1301: chan_mark_dead(c);
1.104 markus 1302: } else if (ret == 0) {
1303: debug2("channel %d: pre_dynamic: need more", c->self);
1304: /* need more */
1305: FD_SET(c->sock, readset);
1306: } else {
1307: /* switch to the next state */
1308: c->type = SSH_CHANNEL_OPENING;
1309: port_open_helper(c, "direct-tcpip");
1310: }
1.103 markus 1311: }
1312:
1.41 markus 1313: /* This is our fake X11 server socket. */
1.259 stevesk 1314: /* ARGSUSED */
1.127 itojun 1315: static void
1.237 deraadt 1316: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1317: {
1.113 markus 1318: Channel *nc;
1.285 djm 1319: struct sockaddr_storage addr;
1.320 markus 1320: int newsock, oerrno;
1.41 markus 1321: socklen_t addrlen;
1.85 markus 1322: char buf[16384], *remote_ipaddr;
1.51 markus 1323: int remote_port;
1.25 markus 1324:
1.41 markus 1325: if (FD_ISSET(c->sock, readset)) {
1326: debug("X11 connection requested.");
1327: addrlen = sizeof(addr);
1.285 djm 1328: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.149 markus 1329: if (c->single_connection) {
1.320 markus 1330: oerrno = errno;
1.194 markus 1331: debug2("single_connection: closing X11 listener.");
1.149 markus 1332: channel_close_fd(&c->sock);
1333: chan_mark_dead(c);
1.320 markus 1334: errno = oerrno;
1.149 markus 1335: }
1.41 markus 1336: if (newsock < 0) {
1.320 markus 1337: if (errno != EINTR && errno != EWOULDBLOCK &&
1338: errno != ECONNABORTED)
1339: error("accept: %.100s", strerror(errno));
1.317 djm 1340: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1341: c->notbefore = monotime() + 1;
1.41 markus 1342: return;
1343: }
1.162 stevesk 1344: set_nodelay(newsock);
1.85 markus 1345: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1346: remote_port = get_peer_port(newsock);
1.41 markus 1347: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1348: remote_ipaddr, remote_port);
1.51 markus 1349:
1.113 markus 1350: nc = channel_new("accepted x11 socket",
1.51 markus 1351: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1352: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.51 markus 1353: if (compat20) {
1354: packet_start(SSH2_MSG_CHANNEL_OPEN);
1355: packet_put_cstring("x11");
1.113 markus 1356: packet_put_int(nc->self);
1.149 markus 1357: packet_put_int(nc->local_window_max);
1358: packet_put_int(nc->local_maxpacket);
1.85 markus 1359: /* originator ipaddr and port */
1360: packet_put_cstring(remote_ipaddr);
1.57 markus 1361: if (datafellows & SSH_BUG_X11FWD) {
1.194 markus 1362: debug2("ssh2 x11 bug compat mode");
1.57 markus 1363: } else {
1364: packet_put_int(remote_port);
1365: }
1.51 markus 1366: packet_send();
1367: } else {
1368: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1369: packet_put_int(nc->self);
1.121 markus 1370: if (packet_get_protocol_flags() &
1371: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1372: packet_put_cstring(buf);
1.51 markus 1373: packet_send();
1374: }
1.321 djm 1375: free(remote_ipaddr);
1.41 markus 1376: }
1377: }
1.25 markus 1378:
1.127 itojun 1379: static void
1.103 markus 1380: port_open_helper(Channel *c, char *rtype)
1381: {
1382: int direct;
1383: char buf[1024];
1.328 djm 1384: char *local_ipaddr = get_local_ipaddr(c->sock);
1.330 djm 1385: int local_port = c->sock == -1 ? 65536 : get_sock_port(c->sock, 1);
1.103 markus 1386: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1387: int remote_port = get_peer_port(c->sock);
1.303 djm 1388:
1389: if (remote_port == -1) {
1390: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1391: free(remote_ipaddr);
1.303 djm 1392: remote_ipaddr = xstrdup("127.0.0.1");
1393: remote_port = 65535;
1394: }
1.103 markus 1395:
1396: direct = (strcmp(rtype, "direct-tcpip") == 0);
1397:
1398: snprintf(buf, sizeof buf,
1399: "%s: listening port %d for %.100s port %d, "
1.328 djm 1400: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1401: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1402: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1403:
1.321 djm 1404: free(c->remote_name);
1.103 markus 1405: c->remote_name = xstrdup(buf);
1406:
1407: if (compat20) {
1408: packet_start(SSH2_MSG_CHANNEL_OPEN);
1409: packet_put_cstring(rtype);
1410: packet_put_int(c->self);
1411: packet_put_int(c->local_window_max);
1412: packet_put_int(c->local_maxpacket);
1413: if (direct) {
1414: /* target host, port */
1415: packet_put_cstring(c->path);
1416: packet_put_int(c->host_port);
1417: } else {
1418: /* listen address, port */
1419: packet_put_cstring(c->path);
1.328 djm 1420: packet_put_int(local_port);
1.103 markus 1421: }
1422: /* originator host and port */
1423: packet_put_cstring(remote_ipaddr);
1.216 markus 1424: packet_put_int((u_int)remote_port);
1.103 markus 1425: packet_send();
1426: } else {
1427: packet_start(SSH_MSG_PORT_OPEN);
1428: packet_put_int(c->self);
1429: packet_put_cstring(c->path);
1430: packet_put_int(c->host_port);
1.121 markus 1431: if (packet_get_protocol_flags() &
1432: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1433: packet_put_cstring(c->remote_name);
1434: packet_send();
1435: }
1.321 djm 1436: free(remote_ipaddr);
1.328 djm 1437: free(local_ipaddr);
1.103 markus 1438: }
1439:
1.226 djm 1440: static void
1441: channel_set_reuseaddr(int fd)
1442: {
1443: int on = 1;
1444:
1445: /*
1446: * Set socket options.
1447: * Allow local port reuse in TIME_WAIT.
1448: */
1449: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1450: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1451: }
1452:
1.41 markus 1453: /*
1454: * This socket is listening for connections to a forwarded TCP/IP port.
1455: */
1.259 stevesk 1456: /* ARGSUSED */
1.127 itojun 1457: static void
1.237 deraadt 1458: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1459: {
1.103 markus 1460: Channel *nc;
1.285 djm 1461: struct sockaddr_storage addr;
1.113 markus 1462: int newsock, nextstate;
1.41 markus 1463: socklen_t addrlen;
1.103 markus 1464: char *rtype;
1.73 markus 1465:
1.41 markus 1466: if (FD_ISSET(c->sock, readset)) {
1467: debug("Connection to port %d forwarding "
1468: "to %.100s port %d requested.",
1469: c->listening_port, c->path, c->host_port);
1.103 markus 1470:
1.137 markus 1471: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1472: nextstate = SSH_CHANNEL_OPENING;
1473: rtype = "forwarded-tcpip";
1474: } else {
1475: if (c->host_port == 0) {
1476: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1477: rtype = "dynamic-tcpip";
1.137 markus 1478: } else {
1479: nextstate = SSH_CHANNEL_OPENING;
1480: rtype = "direct-tcpip";
1481: }
1482: }
1.103 markus 1483:
1.41 markus 1484: addrlen = sizeof(addr);
1.285 djm 1485: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1486: if (newsock < 0) {
1.320 markus 1487: if (errno != EINTR && errno != EWOULDBLOCK &&
1488: errno != ECONNABORTED)
1489: error("accept: %.100s", strerror(errno));
1.317 djm 1490: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1491: c->notbefore = monotime() + 1;
1.41 markus 1492: return;
1493: }
1.169 stevesk 1494: set_nodelay(newsock);
1.190 markus 1495: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1496: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1497: nc->listening_port = c->listening_port;
1498: nc->host_port = c->host_port;
1.293 djm 1499: if (c->path != NULL)
1500: nc->path = xstrdup(c->path);
1.103 markus 1501:
1.299 markus 1502: if (nextstate != SSH_CHANNEL_DYNAMIC)
1.103 markus 1503: port_open_helper(nc, rtype);
1.41 markus 1504: }
1505: }
1.25 markus 1506:
1.41 markus 1507: /*
1508: * This is the authentication agent socket listening for connections from
1509: * clients.
1510: */
1.259 stevesk 1511: /* ARGSUSED */
1.127 itojun 1512: static void
1.237 deraadt 1513: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1514: {
1.113 markus 1515: Channel *nc;
1516: int newsock;
1.285 djm 1517: struct sockaddr_storage addr;
1.41 markus 1518: socklen_t addrlen;
1.25 markus 1519:
1.41 markus 1520: if (FD_ISSET(c->sock, readset)) {
1521: addrlen = sizeof(addr);
1.285 djm 1522: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1523: if (newsock < 0) {
1.317 djm 1524: error("accept from auth socket: %.100s",
1525: strerror(errno));
1526: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1527: c->notbefore = monotime() + 1;
1.41 markus 1528: return;
1529: }
1.113 markus 1530: nc = channel_new("accepted auth socket",
1.73 markus 1531: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1532: c->local_window_max, c->local_maxpacket,
1.190 markus 1533: 0, "accepted auth socket", 1);
1.73 markus 1534: if (compat20) {
1535: packet_start(SSH2_MSG_CHANNEL_OPEN);
1536: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1537: packet_put_int(nc->self);
1.73 markus 1538: packet_put_int(c->local_window_max);
1539: packet_put_int(c->local_maxpacket);
1540: } else {
1541: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1542: packet_put_int(nc->self);
1.73 markus 1543: }
1.41 markus 1544: packet_send();
1545: }
1546: }
1.25 markus 1547:
1.259 stevesk 1548: /* ARGSUSED */
1.127 itojun 1549: static void
1.237 deraadt 1550: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1551: {
1.276 djm 1552: int err = 0, sock;
1.129 stevesk 1553: socklen_t sz = sizeof(err);
1.114 markus 1554:
1.75 markus 1555: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1556: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1557: err = errno;
1558: error("getsockopt SO_ERROR failed");
1559: }
1560: if (err == 0) {
1.276 djm 1561: debug("channel %d: connected to %s port %d",
1562: c->self, c->connect_ctx.host, c->connect_ctx.port);
1563: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1564: c->type = SSH_CHANNEL_OPEN;
1565: if (compat20) {
1566: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1567: packet_put_int(c->remote_id);
1568: packet_put_int(c->self);
1569: packet_put_int(c->local_window);
1570: packet_put_int(c->local_maxpacket);
1571: } else {
1572: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1573: packet_put_int(c->remote_id);
1574: packet_put_int(c->self);
1575: }
1.75 markus 1576: } else {
1.276 djm 1577: debug("channel %d: connection failed: %s",
1.114 markus 1578: c->self, strerror(err));
1.276 djm 1579: /* Try next address, if any */
1580: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1581: close(c->sock);
1582: c->sock = c->rfd = c->wfd = sock;
1583: channel_max_fd = channel_find_maxfd();
1584: return;
1585: }
1586: /* Exhausted all addresses */
1587: error("connect_to %.100s port %d: failed.",
1588: c->connect_ctx.host, c->connect_ctx.port);
1589: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1590: if (compat20) {
1591: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1592: packet_put_int(c->remote_id);
1593: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1594: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1595: packet_put_cstring(strerror(err));
1596: packet_put_cstring("");
1597: }
1.75 markus 1598: } else {
1.114 markus 1599: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1600: packet_put_int(c->remote_id);
1.75 markus 1601: }
1.114 markus 1602: chan_mark_dead(c);
1.75 markus 1603: }
1.114 markus 1604: packet_send();
1.75 markus 1605: }
1606: }
1607:
1.259 stevesk 1608: /* ARGSUSED */
1.127 itojun 1609: static int
1.237 deraadt 1610: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1611: {
1.214 markus 1612: char buf[CHAN_RBUF];
1.41 markus 1613: int len;
1.25 markus 1614:
1.118 markus 1615: if (c->rfd != -1 &&
1.41 markus 1616: FD_ISSET(c->rfd, readset)) {
1617: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1618: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1619: return 1;
1.41 markus 1620: if (len <= 0) {
1.194 markus 1621: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1622: c->self, c->rfd, len);
1.104 markus 1623: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1624: debug2("channel %d: not open", c->self);
1.113 markus 1625: chan_mark_dead(c);
1.103 markus 1626: return -1;
1.104 markus 1627: } else if (compat13) {
1.158 markus 1628: buffer_clear(&c->output);
1.41 markus 1629: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.194 markus 1630: debug2("channel %d: input draining.", c->self);
1.25 markus 1631: } else {
1.41 markus 1632: chan_read_failed(c);
1.25 markus 1633: }
1.41 markus 1634: return -1;
1635: }
1.143 deraadt 1636: if (c->input_filter != NULL) {
1.66 markus 1637: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1638: debug2("channel %d: filter stops", c->self);
1.65 markus 1639: chan_read_failed(c);
1640: }
1.228 reyk 1641: } else if (c->datagram) {
1642: buffer_put_string(&c->input, buf, len);
1.65 markus 1643: } else {
1644: buffer_append(&c->input, buf, len);
1645: }
1.41 markus 1646: }
1647: return 1;
1648: }
1.241 deraadt 1649:
1.259 stevesk 1650: /* ARGSUSED */
1.127 itojun 1651: static int
1.237 deraadt 1652: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1653: {
1.95 markus 1654: struct termios tio;
1.231 reyk 1655: u_char *data = NULL, *buf;
1.309 djm 1656: u_int dlen, olen = 0;
1.41 markus 1657: int len;
1.25 markus 1658:
1.41 markus 1659: /* Send buffered output data to the socket. */
1.118 markus 1660: if (c->wfd != -1 &&
1.41 markus 1661: FD_ISSET(c->wfd, writeset) &&
1662: buffer_len(&c->output) > 0) {
1.309 djm 1663: olen = buffer_len(&c->output);
1.231 reyk 1664: if (c->output_filter != NULL) {
1665: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1666: debug2("channel %d: filter stops", c->self);
1.232 reyk 1667: if (c->type != SSH_CHANNEL_OPEN)
1668: chan_mark_dead(c);
1669: else
1670: chan_write_failed(c);
1671: return -1;
1.231 reyk 1672: }
1673: } else if (c->datagram) {
1674: buf = data = buffer_get_string(&c->output, &dlen);
1675: } else {
1676: buf = data = buffer_ptr(&c->output);
1677: dlen = buffer_len(&c->output);
1678: }
1679:
1.228 reyk 1680: if (c->datagram) {
1681: /* ignore truncated writes, datagrams might get lost */
1.231 reyk 1682: len = write(c->wfd, buf, dlen);
1.321 djm 1683: free(data);
1.228 reyk 1684: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1685: return 1;
1686: if (len <= 0) {
1687: if (c->type != SSH_CHANNEL_OPEN)
1688: chan_mark_dead(c);
1689: else
1690: chan_write_failed(c);
1691: return -1;
1692: }
1.309 djm 1693: goto out;
1.228 reyk 1694: }
1.231 reyk 1695:
1696: len = write(c->wfd, buf, dlen);
1.53 markus 1697: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1698: return 1;
1.41 markus 1699: if (len <= 0) {
1.104 markus 1700: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1701: debug2("channel %d: not open", c->self);
1.113 markus 1702: chan_mark_dead(c);
1.104 markus 1703: return -1;
1704: } else if (compat13) {
1.158 markus 1705: buffer_clear(&c->output);
1.194 markus 1706: debug2("channel %d: input draining.", c->self);
1.41 markus 1707: c->type = SSH_CHANNEL_INPUT_DRAINING;
1708: } else {
1709: chan_write_failed(c);
1710: }
1711: return -1;
1.91 markus 1712: }
1.231 reyk 1713: if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1714: if (tcgetattr(c->wfd, &tio) == 0 &&
1715: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1716: /*
1717: * Simulate echo to reduce the impact of
1.96 markus 1718: * traffic analysis. We need to match the
1.95 markus 1719: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1720: * (4 byte channel id + buf)
1.91 markus 1721: */
1.95 markus 1722: packet_send_ignore(4 + len);
1.91 markus 1723: packet_send();
1724: }
1.25 markus 1725: }
1.41 markus 1726: buffer_consume(&c->output, len);
1.44 markus 1727: }
1.309 djm 1728: out:
1729: if (compat20 && olen > 0)
1730: c->local_consumed += olen - buffer_len(&c->output);
1.44 markus 1731: return 1;
1732: }
1.241 deraadt 1733:
1.127 itojun 1734: static int
1.237 deraadt 1735: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1736: {
1.214 markus 1737: char buf[CHAN_RBUF];
1.44 markus 1738: int len;
1739:
1.45 markus 1740: /** XXX handle drain efd, too */
1.44 markus 1741: if (c->efd != -1) {
1742: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1743: FD_ISSET(c->efd, writeset) &&
1744: buffer_len(&c->extended) > 0) {
1745: len = write(c->efd, buffer_ptr(&c->extended),
1746: buffer_len(&c->extended));
1.70 markus 1747: debug2("channel %d: written %d to efd %d",
1.44 markus 1748: c->self, len, c->efd);
1.93 markus 1749: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1750: return 1;
1751: if (len <= 0) {
1752: debug2("channel %d: closing write-efd %d",
1753: c->self, c->efd);
1.132 markus 1754: channel_close_fd(&c->efd);
1.93 markus 1755: } else {
1.44 markus 1756: buffer_consume(&c->extended, len);
1757: c->local_consumed += len;
1758: }
1.306 djm 1759: } else if (c->efd != -1 &&
1760: (c->extended_usage == CHAN_EXTENDED_READ ||
1761: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 1762: FD_ISSET(c->efd, readset)) {
1763: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1764: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1765: c->self, len, c->efd);
1.93 markus 1766: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1767: return 1;
1768: if (len <= 0) {
1769: debug2("channel %d: closing read-efd %d",
1.45 markus 1770: c->self, c->efd);
1.132 markus 1771: channel_close_fd(&c->efd);
1.93 markus 1772: } else {
1.306 djm 1773: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
1774: debug3("channel %d: discard efd",
1775: c->self);
1776: } else
1777: buffer_append(&c->extended, buf, len);
1.93 markus 1778: }
1.44 markus 1779: }
1780: }
1781: return 1;
1782: }
1.241 deraadt 1783:
1.259 stevesk 1784: /* ARGSUSED */
1.127 itojun 1785: static int
1.93 markus 1786: channel_check_window(Channel *c)
1.44 markus 1787: {
1.104 markus 1788: if (c->type == SSH_CHANNEL_OPEN &&
1789: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 1790: ((c->local_window_max - c->local_window >
1.269 markus 1791: c->local_maxpacket*3) ||
1792: c->local_window < c->local_window_max/2) &&
1.44 markus 1793: c->local_consumed > 0) {
1794: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1795: packet_put_int(c->remote_id);
1796: packet_put_int(c->local_consumed);
1797: packet_send();
1.70 markus 1798: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1799: c->self, c->local_window,
1800: c->local_consumed);
1801: c->local_window += c->local_consumed;
1802: c->local_consumed = 0;
1.1 deraadt 1803: }
1.41 markus 1804: return 1;
1.1 deraadt 1805: }
1806:
1.127 itojun 1807: static void
1.237 deraadt 1808: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1809: {
1810: channel_handle_rfd(c, readset, writeset);
1811: channel_handle_wfd(c, readset, writeset);
1.157 markus 1812: if (!compat20)
1.137 markus 1813: return;
1.44 markus 1814: channel_handle_efd(c, readset, writeset);
1.93 markus 1815: channel_check_window(c);
1.44 markus 1816: }
1817:
1.302 djm 1818: static u_int
1819: read_mux(Channel *c, u_int need)
1820: {
1821: char buf[CHAN_RBUF];
1822: int len;
1823: u_int rlen;
1824:
1825: if (buffer_len(&c->input) < need) {
1826: rlen = need - buffer_len(&c->input);
1827: len = read(c->rfd, buf, MIN(rlen, CHAN_RBUF));
1828: if (len <= 0) {
1829: if (errno != EINTR && errno != EAGAIN) {
1830: debug2("channel %d: ctl read<=0 rfd %d len %d",
1831: c->self, c->rfd, len);
1832: chan_read_failed(c);
1833: return 0;
1834: }
1835: } else
1836: buffer_append(&c->input, buf, len);
1837: }
1838: return buffer_len(&c->input);
1839: }
1840:
1841: static void
1842: channel_post_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
1843: {
1844: u_int need;
1845: ssize_t len;
1846:
1847: if (!compat20)
1848: fatal("%s: entered with !compat20", __func__);
1849:
1.304 djm 1850: if (c->rfd != -1 && !c->mux_pause && FD_ISSET(c->rfd, readset) &&
1.302 djm 1851: (c->istate == CHAN_INPUT_OPEN ||
1852: c->istate == CHAN_INPUT_WAIT_DRAIN)) {
1853: /*
1854: * Don't not read past the precise end of packets to
1855: * avoid disrupting fd passing.
1856: */
1857: if (read_mux(c, 4) < 4) /* read header */
1858: return;
1859: need = get_u32(buffer_ptr(&c->input));
1860: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1861: if (need > CHANNEL_MUX_MAX_PACKET) {
1862: debug2("channel %d: packet too big %u > %u",
1863: c->self, CHANNEL_MUX_MAX_PACKET, need);
1864: chan_rcvd_oclose(c);
1865: return;
1866: }
1867: if (read_mux(c, need + 4) < need + 4) /* read body */
1868: return;
1869: if (c->mux_rcb(c) != 0) {
1870: debug("channel %d: mux_rcb failed", c->self);
1871: chan_mark_dead(c);
1872: return;
1873: }
1874: }
1875:
1876: if (c->wfd != -1 && FD_ISSET(c->wfd, writeset) &&
1877: buffer_len(&c->output) > 0) {
1878: len = write(c->wfd, buffer_ptr(&c->output),
1879: buffer_len(&c->output));
1880: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1881: return;
1882: if (len <= 0) {
1883: chan_mark_dead(c);
1884: return;
1885: }
1886: buffer_consume(&c->output, len);
1887: }
1888: }
1889:
1890: static void
1891: channel_post_mux_listener(Channel *c, fd_set *readset, fd_set *writeset)
1892: {
1893: Channel *nc;
1894: struct sockaddr_storage addr;
1895: socklen_t addrlen;
1896: int newsock;
1897: uid_t euid;
1898: gid_t egid;
1899:
1900: if (!FD_ISSET(c->sock, readset))
1901: return;
1902:
1903: debug("multiplexing control connection");
1904:
1905: /*
1906: * Accept connection on control socket
1907: */
1908: memset(&addr, 0, sizeof(addr));
1909: addrlen = sizeof(addr);
1910: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
1911: &addrlen)) == -1) {
1912: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 1913: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1914: c->notbefore = monotime() + 1;
1.302 djm 1915: return;
1916: }
1917:
1918: if (getpeereid(newsock, &euid, &egid) < 0) {
1919: error("%s getpeereid failed: %s", __func__,
1920: strerror(errno));
1921: close(newsock);
1922: return;
1923: }
1924: if ((euid != 0) && (getuid() != euid)) {
1925: error("multiplex uid mismatch: peer euid %u != uid %u",
1926: (u_int)euid, (u_int)getuid());
1927: close(newsock);
1928: return;
1929: }
1930: nc = channel_new("multiplex client", SSH_CHANNEL_MUX_CLIENT,
1931: newsock, newsock, -1, c->local_window_max,
1932: c->local_maxpacket, 0, "mux-control", 1);
1933: nc->mux_rcb = c->mux_rcb;
1934: debug3("%s: new mux channel %d fd %d", __func__,
1935: nc->self, nc->sock);
1936: /* establish state */
1937: nc->mux_rcb(nc);
1938: /* mux state transitions must not elicit protocol messages */
1939: nc->flags |= CHAN_LOCAL;
1940: }
1941:
1.259 stevesk 1942: /* ARGSUSED */
1.127 itojun 1943: static void
1.237 deraadt 1944: channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
1.1 deraadt 1945: {
1.41 markus 1946: int len;
1.180 deraadt 1947:
1.41 markus 1948: /* Send buffered output data to the socket. */
1949: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1950: len = write(c->sock, buffer_ptr(&c->output),
1951: buffer_len(&c->output));
1952: if (len <= 0)
1.158 markus 1953: buffer_clear(&c->output);
1.41 markus 1954: else
1955: buffer_consume(&c->output, len);
1956: }
1957: }
1.25 markus 1958:
1.127 itojun 1959: static void
1.44 markus 1960: channel_handler_init_20(void)
1961: {
1.157 markus 1962: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1963: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1964: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1965: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1966: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1967: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1968: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1969: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.302 djm 1970: channel_pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
1971: channel_pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
1.44 markus 1972:
1.157 markus 1973: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1974: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1975: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1976: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1977: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1978: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1979: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.302 djm 1980: channel_post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
1981: channel_post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.44 markus 1982: }
1983:
1.127 itojun 1984: static void
1.41 markus 1985: channel_handler_init_13(void)
1986: {
1987: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1988: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1989: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1990: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1991: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1992: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1993: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1994: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1995: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1996:
1.157 markus 1997: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 1998: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1999: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2000: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2001: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 2002: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 2003: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 2004: }
1.25 markus 2005:
1.127 itojun 2006: static void
1.41 markus 2007: channel_handler_init_15(void)
2008: {
1.157 markus 2009: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 2010: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 2011: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2012: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2013: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 2014: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 2015: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 2016:
1.41 markus 2017: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2018: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2019: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 2020: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 2021: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 2022: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 2023: }
1.27 markus 2024:
1.127 itojun 2025: static void
1.41 markus 2026: channel_handler_init(void)
2027: {
2028: int i;
1.180 deraadt 2029:
1.148 deraadt 2030: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 2031: channel_pre[i] = NULL;
2032: channel_post[i] = NULL;
2033: }
1.44 markus 2034: if (compat20)
2035: channel_handler_init_20();
2036: else if (compat13)
1.41 markus 2037: channel_handler_init_13();
2038: else
2039: channel_handler_init_15();
2040: }
1.25 markus 2041:
1.140 markus 2042: /* gc dead channels */
2043: static void
2044: channel_garbage_collect(Channel *c)
2045: {
2046: if (c == NULL)
2047: return;
2048: if (c->detach_user != NULL) {
1.225 djm 2049: if (!chan_is_dead(c, c->detach_close))
1.140 markus 2050: return;
1.194 markus 2051: debug2("channel %d: gc: notify user", c->self);
1.140 markus 2052: c->detach_user(c->self, NULL);
2053: /* if we still have a callback */
2054: if (c->detach_user != NULL)
2055: return;
1.194 markus 2056: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2057: }
2058: if (!chan_is_dead(c, 1))
2059: return;
1.194 markus 2060: debug2("channel %d: garbage collecting", c->self);
1.140 markus 2061: channel_free(c);
2062: }
2063:
1.127 itojun 2064: static void
1.317 djm 2065: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset,
2066: time_t *unpause_secs)
1.41 markus 2067: {
2068: static int did_init = 0;
1.299 markus 2069: u_int i, oalloc;
1.41 markus 2070: Channel *c;
1.317 djm 2071: time_t now;
1.25 markus 2072:
1.41 markus 2073: if (!did_init) {
2074: channel_handler_init();
2075: did_init = 1;
2076: }
1.322 dtucker 2077: now = monotime();
1.317 djm 2078: if (unpause_secs != NULL)
2079: *unpause_secs = 0;
1.299 markus 2080: for (i = 0, oalloc = channels_alloc; i < oalloc; i++) {
1.113 markus 2081: c = channels[i];
2082: if (c == NULL)
1.41 markus 2083: continue;
1.299 markus 2084: if (c->delayed) {
2085: if (ftab == channel_pre)
2086: c->delayed = 0;
2087: else
2088: continue;
2089: }
1.317 djm 2090: if (ftab[c->type] != NULL) {
2091: /*
2092: * Run handlers that are not paused.
2093: */
2094: if (c->notbefore <= now)
2095: (*ftab[c->type])(c, readset, writeset);
2096: else if (unpause_secs != NULL) {
2097: /*
2098: * Collect the time that the earliest
2099: * channel comes off pause.
2100: */
2101: debug3("%s: chan %d: skip for %d more seconds",
2102: __func__, c->self,
2103: (int)(c->notbefore - now));
2104: if (*unpause_secs == 0 ||
2105: (c->notbefore - now) < *unpause_secs)
2106: *unpause_secs = c->notbefore - now;
2107: }
2108: }
1.140 markus 2109: channel_garbage_collect(c);
1.1 deraadt 2110: }
1.317 djm 2111: if (unpause_secs != NULL && *unpause_secs != 0)
2112: debug3("%s: first channel unpauses in %d seconds",
2113: __func__, (int)*unpause_secs);
1.1 deraadt 2114: }
2115:
1.121 markus 2116: /*
2117: * Allocate/update select bitmasks and add any bits relevant to channels in
2118: * select bitmasks.
2119: */
1.49 markus 2120: void
1.100 markus 2121: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.318 djm 2122: u_int *nallocp, time_t *minwait_secs, int rekeying)
1.41 markus 2123: {
1.243 djm 2124: u_int n, sz, nfdset;
1.84 markus 2125:
2126: n = MAX(*maxfdp, channel_max_fd);
2127:
1.243 djm 2128: nfdset = howmany(n+1, NFDBITS);
2129: /* Explicitly test here, because xrealloc isn't always called */
2130: if (nfdset && SIZE_T_MAX / nfdset < sizeof(fd_mask))
2131: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2132: sz = nfdset * sizeof(fd_mask);
2133:
1.132 markus 2134: /* perhaps check sz < nalloc/2 and shrink? */
2135: if (*readsetp == NULL || sz > *nallocp) {
1.243 djm 2136: *readsetp = xrealloc(*readsetp, nfdset, sizeof(fd_mask));
2137: *writesetp = xrealloc(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2138: *nallocp = sz;
1.84 markus 2139: }
1.132 markus 2140: *maxfdp = n;
1.84 markus 2141: memset(*readsetp, 0, sz);
2142: memset(*writesetp, 0, sz);
2143:
1.100 markus 2144: if (!rekeying)
1.317 djm 2145: channel_handler(channel_pre, *readsetp, *writesetp,
2146: minwait_secs);
1.41 markus 2147: }
2148:
1.121 markus 2149: /*
2150: * After select, perform any appropriate operations for channels which have
2151: * events pending.
2152: */
1.49 markus 2153: void
1.237 deraadt 2154: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 2155: {
1.317 djm 2156: channel_handler(channel_post, readset, writeset, NULL);
1.41 markus 2157: }
2158:
1.121 markus 2159:
1.84 markus 2160: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2161: void
1.142 itojun 2162: channel_output_poll(void)
1.1 deraadt 2163: {
1.41 markus 2164: Channel *c;
1.209 avsm 2165: u_int i, len;
1.1 deraadt 2166:
1.25 markus 2167: for (i = 0; i < channels_alloc; i++) {
1.113 markus 2168: c = channels[i];
2169: if (c == NULL)
2170: continue;
1.37 markus 2171:
1.121 markus 2172: /*
2173: * We are only interested in channels that can have buffered
2174: * incoming data.
2175: */
1.37 markus 2176: if (compat13) {
1.41 markus 2177: if (c->type != SSH_CHANNEL_OPEN &&
2178: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 2179: continue;
2180: } else {
1.41 markus 2181: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 2182: continue;
2183: }
1.46 markus 2184: if (compat20 &&
2185: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2186: /* XXX is this true? */
1.140 markus 2187: debug3("channel %d: will not send data after close", c->self);
1.44 markus 2188: continue;
2189: }
1.25 markus 2190:
2191: /* Get the amount of buffered data for this channel. */
1.93 markus 2192: if ((c->istate == CHAN_INPUT_OPEN ||
2193: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
2194: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 2195: if (c->datagram) {
2196: if (len > 0) {
2197: u_char *data;
2198: u_int dlen;
2199:
2200: data = buffer_get_string(&c->input,
2201: &dlen);
1.309 djm 2202: if (dlen > c->remote_window ||
2203: dlen > c->remote_maxpacket) {
2204: debug("channel %d: datagram "
2205: "too big for channel",
2206: c->self);
1.321 djm 2207: free(data);
1.309 djm 2208: continue;
2209: }
1.228 reyk 2210: packet_start(SSH2_MSG_CHANNEL_DATA);
2211: packet_put_int(c->remote_id);
2212: packet_put_string(data, dlen);
2213: packet_send();
2214: c->remote_window -= dlen + 4;
1.321 djm 2215: free(data);
1.228 reyk 2216: }
2217: continue;
2218: }
1.121 markus 2219: /*
2220: * Send some data for the other side over the secure
2221: * connection.
2222: */
1.44 markus 2223: if (compat20) {
2224: if (len > c->remote_window)
2225: len = c->remote_window;
2226: if (len > c->remote_maxpacket)
2227: len = c->remote_maxpacket;
1.25 markus 2228: } else {
1.44 markus 2229: if (packet_is_interactive()) {
2230: if (len > 1024)
2231: len = 512;
2232: } else {
2233: /* Keep the packets at reasonable size. */
2234: if (len > packet_get_maxsize()/2)
2235: len = packet_get_maxsize()/2;
2236: }
1.25 markus 2237: }
1.41 markus 2238: if (len > 0) {
1.44 markus 2239: packet_start(compat20 ?
2240: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 2241: packet_put_int(c->remote_id);
2242: packet_put_string(buffer_ptr(&c->input), len);
2243: packet_send();
2244: buffer_consume(&c->input, len);
2245: c->remote_window -= len;
2246: }
2247: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 2248: if (compat13)
2249: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 2250: /*
2251: * input-buffer is empty and read-socket shutdown:
1.172 markus 2252: * tell peer, that we will not send more data: send IEOF.
2253: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 2254: */
1.172 markus 2255: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 2256: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2257: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 2258: else
2259: chan_ibuf_empty(c);
1.25 markus 2260: }
1.44 markus 2261: /* Send extended data, i.e. stderr */
2262: if (compat20 &&
1.172 markus 2263: !(c->flags & CHAN_EOF_SENT) &&
1.44 markus 2264: c->remote_window > 0 &&
2265: (len = buffer_len(&c->extended)) > 0 &&
2266: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 2267: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 2268: c->self, c->remote_window, buffer_len(&c->extended),
2269: c->extended_usage);
1.44 markus 2270: if (len > c->remote_window)
2271: len = c->remote_window;
2272: if (len > c->remote_maxpacket)
2273: len = c->remote_maxpacket;
2274: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
2275: packet_put_int(c->remote_id);
2276: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
2277: packet_put_string(buffer_ptr(&c->extended), len);
2278: packet_send();
2279: buffer_consume(&c->extended, len);
2280: c->remote_window -= len;
1.93 markus 2281: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 2282: }
1.25 markus 2283: }
1.1 deraadt 2284: }
2285:
1.121 markus 2286:
2287: /* -- protocol input */
1.249 djm 2288:
2289: /* ARGSUSED */
1.49 markus 2290: void
1.154 markus 2291: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2292: {
1.37 markus 2293: int id;
1.332 djm 2294: const u_char *data;
1.309 djm 2295: u_int data_len, win_len;
1.41 markus 2296: Channel *c;
1.25 markus 2297:
2298: /* Get the channel number and verify it. */
1.37 markus 2299: id = packet_get_int();
1.41 markus 2300: c = channel_lookup(id);
2301: if (c == NULL)
1.37 markus 2302: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 2303:
2304: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2305: if (c->type != SSH_CHANNEL_OPEN &&
2306: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 2307: return;
2308:
1.25 markus 2309: /* Get the data. */
1.274 markus 2310: data = packet_get_string_ptr(&data_len);
1.309 djm 2311: win_len = data_len;
2312: if (c->datagram)
2313: win_len += 4; /* string length header */
1.200 markus 2314:
2315: /*
2316: * Ignore data for protocol > 1.3 if output end is no longer open.
2317: * For protocol 2 the sending side is reducing its window as it sends
2318: * data, so we must 'fake' consumption of the data in order to ensure
2319: * that window updates are sent back. Otherwise the connection might
2320: * deadlock.
2321: */
2322: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
2323: if (compat20) {
1.309 djm 2324: c->local_window -= win_len;
2325: c->local_consumed += win_len;
1.200 markus 2326: }
2327: return;
2328: }
1.41 markus 2329:
1.143 deraadt 2330: if (compat20) {
1.309 djm 2331: if (win_len > c->local_maxpacket) {
1.188 itojun 2332: logit("channel %d: rcvd big packet %d, maxpack %d",
1.309 djm 2333: c->self, win_len, c->local_maxpacket);
1.44 markus 2334: }
1.309 djm 2335: if (win_len > c->local_window) {
1.188 itojun 2336: logit("channel %d: rcvd too much data %d, win %d",
1.309 djm 2337: c->self, win_len, c->local_window);
1.44 markus 2338: return;
2339: }
1.309 djm 2340: c->local_window -= win_len;
1.44 markus 2341: }
1.228 reyk 2342: if (c->datagram)
2343: buffer_put_string(&c->output, data, data_len);
2344: else
2345: buffer_append(&c->output, data, data_len);
1.274 markus 2346: packet_check_eom();
1.1 deraadt 2347: }
1.121 markus 2348:
1.249 djm 2349: /* ARGSUSED */
1.49 markus 2350: void
1.154 markus 2351: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2352: {
2353: int id;
2354: char *data;
1.177 markus 2355: u_int data_len, tcode;
1.44 markus 2356: Channel *c;
2357:
2358: /* Get the channel number and verify it. */
2359: id = packet_get_int();
2360: c = channel_lookup(id);
2361:
2362: if (c == NULL)
2363: packet_disconnect("Received extended_data for bad channel %d.", id);
2364: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2365: logit("channel %d: ext data for non open", id);
1.44 markus 2366: return;
1.172 markus 2367: }
2368: if (c->flags & CHAN_EOF_RCVD) {
2369: if (datafellows & SSH_BUG_EXTEOF)
2370: debug("channel %d: accepting ext data after eof", id);
2371: else
2372: packet_disconnect("Received extended_data after EOF "
2373: "on channel %d.", id);
1.44 markus 2374: }
2375: tcode = packet_get_int();
2376: if (c->efd == -1 ||
2377: c->extended_usage != CHAN_EXTENDED_WRITE ||
2378: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2379: logit("channel %d: bad ext data", c->self);
1.44 markus 2380: return;
2381: }
2382: data = packet_get_string(&data_len);
1.152 markus 2383: packet_check_eom();
1.44 markus 2384: if (data_len > c->local_window) {
1.188 itojun 2385: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2386: c->self, data_len, c->local_window);
1.321 djm 2387: free(data);
1.44 markus 2388: return;
2389: }
1.70 markus 2390: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2391: c->local_window -= data_len;
2392: buffer_append(&c->extended, data, data_len);
1.321 djm 2393: free(data);
1.44 markus 2394: }
2395:
1.249 djm 2396: /* ARGSUSED */
1.49 markus 2397: void
1.154 markus 2398: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2399: {
2400: int id;
2401: Channel *c;
2402:
2403: id = packet_get_int();
1.152 markus 2404: packet_check_eom();
1.41 markus 2405: c = channel_lookup(id);
2406: if (c == NULL)
2407: packet_disconnect("Received ieof for nonexistent channel %d.", id);
2408: chan_rcvd_ieof(c);
1.133 markus 2409:
2410: /* XXX force input close */
1.156 markus 2411: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2412: debug("channel %d: FORCE input drain", c->self);
2413: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2414: if (buffer_len(&c->input) == 0)
2415: chan_ibuf_empty(c);
1.133 markus 2416: }
2417:
1.41 markus 2418: }
1.1 deraadt 2419:
1.249 djm 2420: /* ARGSUSED */
1.49 markus 2421: void
1.154 markus 2422: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2423: {
1.41 markus 2424: int id;
2425: Channel *c;
1.1 deraadt 2426:
1.41 markus 2427: id = packet_get_int();
1.152 markus 2428: packet_check_eom();
1.41 markus 2429: c = channel_lookup(id);
2430: if (c == NULL)
2431: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 2432:
2433: /*
2434: * Send a confirmation that we have closed the channel and no more
2435: * data is coming for it.
2436: */
1.25 markus 2437: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 2438: packet_put_int(c->remote_id);
1.25 markus 2439: packet_send();
2440:
1.27 markus 2441: /*
2442: * If the channel is in closed state, we have sent a close request,
2443: * and the other side will eventually respond with a confirmation.
2444: * Thus, we cannot free the channel here, because then there would be
2445: * no-one to receive the confirmation. The channel gets freed when
2446: * the confirmation arrives.
2447: */
1.41 markus 2448: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 2449: /*
2450: * Not a closed channel - mark it as draining, which will
2451: * cause it to be freed later.
2452: */
1.158 markus 2453: buffer_clear(&c->input);
1.41 markus 2454: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 2455: }
1.1 deraadt 2456: }
2457:
1.41 markus 2458: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.249 djm 2459: /* ARGSUSED */
1.49 markus 2460: void
1.154 markus 2461: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2462: {
2463: int id = packet_get_int();
2464: Channel *c = channel_lookup(id);
1.151 markus 2465:
1.152 markus 2466: packet_check_eom();
1.41 markus 2467: if (c == NULL)
2468: packet_disconnect("Received oclose for nonexistent channel %d.", id);
2469: chan_rcvd_oclose(c);
2470: }
1.1 deraadt 2471:
1.249 djm 2472: /* ARGSUSED */
1.49 markus 2473: void
1.154 markus 2474: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2475: {
1.41 markus 2476: int id = packet_get_int();
2477: Channel *c = channel_lookup(id);
1.1 deraadt 2478:
1.152 markus 2479: packet_check_eom();
1.41 markus 2480: if (c == NULL)
2481: packet_disconnect("Received close confirmation for "
2482: "out-of-range channel %d.", id);
1.323 dtucker 2483: if (c->type != SSH_CHANNEL_CLOSED && c->type != SSH_CHANNEL_ABANDONED)
1.41 markus 2484: packet_disconnect("Received close confirmation for "
2485: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 2486: channel_free(c);
1.1 deraadt 2487: }
2488:
1.249 djm 2489: /* ARGSUSED */
1.49 markus 2490: void
1.154 markus 2491: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2492: {
1.41 markus 2493: int id, remote_id;
2494: Channel *c;
1.1 deraadt 2495:
1.41 markus 2496: id = packet_get_int();
2497: c = channel_lookup(id);
1.25 markus 2498:
1.41 markus 2499: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2500: packet_disconnect("Received open confirmation for "
2501: "non-opening channel %d.", id);
2502: remote_id = packet_get_int();
1.27 markus 2503: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2504: c->remote_id = remote_id;
2505: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2506:
2507: if (compat20) {
2508: c->remote_window = packet_get_int();
2509: c->remote_maxpacket = packet_get_int();
1.275 djm 2510: if (c->open_confirm) {
1.70 markus 2511: debug2("callback start");
1.304 djm 2512: c->open_confirm(c->self, 1, c->open_confirm_ctx);
1.70 markus 2513: debug2("callback done");
1.44 markus 2514: }
1.194 markus 2515: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
1.44 markus 2516: c->remote_window, c->remote_maxpacket);
2517: }
1.152 markus 2518: packet_check_eom();
1.1 deraadt 2519: }
2520:
1.127 itojun 2521: static char *
1.114 markus 2522: reason2txt(int reason)
2523: {
1.143 deraadt 2524: switch (reason) {
1.114 markus 2525: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2526: return "administratively prohibited";
2527: case SSH2_OPEN_CONNECT_FAILED:
2528: return "connect failed";
2529: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2530: return "unknown channel type";
2531: case SSH2_OPEN_RESOURCE_SHORTAGE:
2532: return "resource shortage";
2533: }
1.117 stevesk 2534: return "unknown reason";
1.114 markus 2535: }
2536:
1.249 djm 2537: /* ARGSUSED */
1.49 markus 2538: void
1.154 markus 2539: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2540: {
1.86 markus 2541: int id, reason;
2542: char *msg = NULL, *lang = NULL;
1.41 markus 2543: Channel *c;
2544:
2545: id = packet_get_int();
2546: c = channel_lookup(id);
1.25 markus 2547:
1.41 markus 2548: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2549: packet_disconnect("Received open failure for "
2550: "non-opening channel %d.", id);
1.44 markus 2551: if (compat20) {
1.86 markus 2552: reason = packet_get_int();
1.110 markus 2553: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 2554: msg = packet_get_string(NULL);
2555: lang = packet_get_string(NULL);
2556: }
1.188 itojun 2557: logit("channel %d: open failed: %s%s%s", id,
1.114 markus 2558: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.321 djm 2559: free(msg);
2560: free(lang);
1.304 djm 2561: if (c->open_confirm) {
2562: debug2("callback start");
2563: c->open_confirm(c->self, 0, c->open_confirm_ctx);
2564: debug2("callback done");
2565: }
1.44 markus 2566: }
1.152 markus 2567: packet_check_eom();
1.291 djm 2568: /* Schedule the channel for cleanup/deletion. */
2569: chan_mark_dead(c);
1.44 markus 2570: }
2571:
1.249 djm 2572: /* ARGSUSED */
1.121 markus 2573: void
1.154 markus 2574: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2575: {
2576: Channel *c;
1.178 markus 2577: int id;
2578: u_int adjust;
1.121 markus 2579:
2580: if (!compat20)
2581: return;
2582:
2583: /* Get the channel number and verify it. */
2584: id = packet_get_int();
2585: c = channel_lookup(id);
1.1 deraadt 2586:
1.229 markus 2587: if (c == NULL) {
2588: logit("Received window adjust for non-open channel %d.", id);
1.121 markus 2589: return;
2590: }
2591: adjust = packet_get_int();
1.152 markus 2592: packet_check_eom();
1.178 markus 2593: debug2("channel %d: rcvd adjust %u", id, adjust);
1.121 markus 2594: c->remote_window += adjust;
2595: }
1.1 deraadt 2596:
1.249 djm 2597: /* ARGSUSED */
1.121 markus 2598: void
1.154 markus 2599: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2600: {
1.121 markus 2601: Channel *c = NULL;
2602: u_short host_port;
2603: char *host, *originator_string;
1.276 djm 2604: int remote_id;
1.121 markus 2605:
2606: remote_id = packet_get_int();
2607: host = packet_get_string(NULL);
2608: host_port = packet_get_int();
1.25 markus 2609:
1.121 markus 2610: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2611: originator_string = packet_get_string(NULL);
2612: } else {
2613: originator_string = xstrdup("unknown (remote did not supply name)");
2614: }
1.152 markus 2615: packet_check_eom();
1.276 djm 2616: c = channel_connect_to(host, host_port,
2617: "connected socket", originator_string);
1.321 djm 2618: free(originator_string);
2619: free(host);
1.121 markus 2620: if (c == NULL) {
2621: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2622: packet_put_int(remote_id);
2623: packet_send();
1.276 djm 2624: } else
2625: c->remote_id = remote_id;
1.1 deraadt 2626: }
2627:
1.275 djm 2628: /* ARGSUSED */
2629: void
2630: channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
2631: {
2632: Channel *c;
2633: struct channel_confirm *cc;
1.289 markus 2634: int id;
1.275 djm 2635:
2636: /* Reset keepalive timeout */
1.296 andreas 2637: packet_set_alive_timeouts(0);
1.275 djm 2638:
1.289 markus 2639: id = packet_get_int();
1.275 djm 2640: packet_check_eom();
2641:
1.289 markus 2642: debug2("channel_input_status_confirm: type %d id %d", type, id);
1.275 djm 2643:
1.289 markus 2644: if ((c = channel_lookup(id)) == NULL) {
2645: logit("channel_input_status_confirm: %d: unknown", id);
1.275 djm 2646: return;
2647: }
2648: ;
2649: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
2650: return;
2651: cc->cb(type, c, cc->ctx);
2652: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 2653: explicit_bzero(cc, sizeof(*cc));
1.321 djm 2654: free(cc);
1.275 djm 2655: }
1.121 markus 2656:
2657: /* -- tcp forwarding */
1.135 markus 2658:
2659: void
2660: channel_set_af(int af)
2661: {
2662: IPv4or6 = af;
2663: }
1.121 markus 2664:
1.312 djm 2665:
2666: /*
2667: * Determine whether or not a port forward listens to loopback, the
2668: * specified address or wildcard. On the client, a specified bind
2669: * address will always override gateway_ports. On the server, a
2670: * gateway_ports of 1 (``yes'') will override the client's specification
2671: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
2672: * will bind to whatever address the client asked for.
2673: *
2674: * Special-case listen_addrs are:
2675: *
2676: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2677: * "" (empty string), "*" -> wildcard v4/v6
2678: * "localhost" -> loopback v4/v6
2679: */
2680: static const char *
2681: channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
2682: int is_client, int gateway_ports)
2683: {
2684: const char *addr = NULL;
2685: int wildcard = 0;
2686:
2687: if (listen_addr == NULL) {
2688: /* No address specified: default to gateway_ports setting */
2689: if (gateway_ports)
2690: wildcard = 1;
2691: } else if (gateway_ports || is_client) {
2692: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
2693: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
2694: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.326 djm 2695: (!is_client && gateway_ports == 1)) {
1.312 djm 2696: wildcard = 1;
1.326 djm 2697: /*
2698: * Notify client if they requested a specific listen
2699: * address and it was overridden.
2700: */
2701: if (*listen_addr != '\0' &&
2702: strcmp(listen_addr, "0.0.0.0") != 0 &&
2703: strcmp(listen_addr, "*") != 0) {
2704: packet_send_debug("Forwarding listen address "
2705: "\"%s\" overridden by server "
2706: "GatewayPorts", listen_addr);
2707: }
2708: }
1.312 djm 2709: else if (strcmp(listen_addr, "localhost") != 0)
2710: addr = listen_addr;
2711: }
2712: if (wildcardp != NULL)
2713: *wildcardp = wildcard;
2714: return addr;
2715: }
2716:
1.160 markus 2717: static int
1.295 djm 2718: channel_setup_fwd_listener(int type, const char *listen_addr,
2719: u_short listen_port, int *allocated_listen_port,
1.160 markus 2720: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
1.25 markus 2721: {
1.113 markus 2722: Channel *c;
1.226 djm 2723: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2724: struct addrinfo hints, *ai, *aitop;
1.212 djm 2725: const char *host, *addr;
1.35 markus 2726: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 2727: in_port_t *lport_p;
1.25 markus 2728:
1.160 markus 2729: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2730: listen_addr : host_to_connect;
1.212 djm 2731: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2732:
1.160 markus 2733: if (host == NULL) {
2734: error("No forward host name.");
1.218 markus 2735: return 0;
1.73 markus 2736: }
1.294 djm 2737: if (strlen(host) >= NI_MAXHOST) {
1.87 markus 2738: error("Forward host name too long.");
1.218 markus 2739: return 0;
1.87 markus 2740: }
1.25 markus 2741:
1.312 djm 2742: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
2743: addr = channel_fwd_bind_addr(listen_addr, &wildcard,
2744: is_client, gateway_ports);
1.212 djm 2745: debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
2746: type, wildcard, (addr == NULL) ? "NULL" : addr);
2747:
2748: /*
1.35 markus 2749: * getaddrinfo returns a loopback address if the hostname is
2750: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2751: */
1.35 markus 2752: memset(&hints, 0, sizeof(hints));
2753: hints.ai_family = IPv4or6;
1.212 djm 2754: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2755: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2756: snprintf(strport, sizeof strport, "%d", listen_port);
1.212 djm 2757: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2758: if (addr == NULL) {
2759: /* This really shouldn't happen */
2760: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 2761: ssh_gai_strerror(r));
1.212 djm 2762: } else {
1.218 markus 2763: error("channel_setup_fwd_listener: "
1.271 dtucker 2764: "getaddrinfo(%.64s): %s", addr,
2765: ssh_gai_strerror(r));
1.212 djm 2766: }
1.218 markus 2767: return 0;
1.212 djm 2768: }
1.295 djm 2769: if (allocated_listen_port != NULL)
2770: *allocated_listen_port = 0;
1.35 markus 2771: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 2772: switch (ai->ai_family) {
2773: case AF_INET:
2774: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
2775: sin_port;
2776: break;
2777: case AF_INET6:
2778: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
2779: sin6_port;
2780: break;
2781: default:
1.35 markus 2782: continue;
1.295 djm 2783: }
2784: /*
2785: * If allocating a port for -R forwards, then use the
2786: * same port for all address families.
2787: */
2788: if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2789: allocated_listen_port != NULL && *allocated_listen_port > 0)
2790: *lport_p = htons(*allocated_listen_port);
2791:
1.35 markus 2792: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2793: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.160 markus 2794: error("channel_setup_fwd_listener: getnameinfo failed");
1.35 markus 2795: continue;
2796: }
2797: /* Create a port to listen for the host. */
1.300 dtucker 2798: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2799: if (sock < 0) {
2800: /* this is no error since kernel may not support ipv6 */
2801: verbose("socket: %.100s", strerror(errno));
2802: continue;
2803: }
1.226 djm 2804:
2805: channel_set_reuseaddr(sock);
1.182 stevesk 2806:
1.295 djm 2807: debug("Local forwarding listening on %s port %s.",
2808: ntop, strport);
1.35 markus 2809:
2810: /* Bind the socket to the address. */
2811: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2812: /* address can be in use ipv6 address is already bound */
2813: verbose("bind: %.100s", strerror(errno));
2814: close(sock);
2815: continue;
2816: }
2817: /* Start listening for connections on the socket. */
1.199 markus 2818: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2819: error("listen: %.100s", strerror(errno));
2820: close(sock);
2821: continue;
2822: }
1.295 djm 2823:
2824: /*
2825: * listen_port == 0 requests a dynamically allocated port -
2826: * record what we got.
2827: */
2828: if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2829: allocated_listen_port != NULL &&
2830: *allocated_listen_port == 0) {
2831: *allocated_listen_port = get_sock_port(sock, 1);
2832: debug("Allocated listen port %d",
2833: *allocated_listen_port);
2834: }
2835:
1.35 markus 2836: /* Allocate a channel number for the socket. */
1.121 markus 2837: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2838: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2839: 0, "port listener", 1);
1.293 djm 2840: c->path = xstrdup(host);
1.113 markus 2841: c->host_port = port_to_connect;
1.312 djm 2842: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.315 markus 2843: if (listen_port == 0 && allocated_listen_port != NULL &&
2844: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
2845: c->listening_port = *allocated_listen_port;
2846: else
2847: c->listening_port = listen_port;
1.35 markus 2848: success = 1;
2849: }
2850: if (success == 0)
1.160 markus 2851: error("channel_setup_fwd_listener: cannot listen to port: %d",
1.87 markus 2852: listen_port);
1.35 markus 2853: freeaddrinfo(aitop);
1.87 markus 2854: return success;
1.25 markus 2855: }
1.1 deraadt 2856:
1.202 djm 2857: int
2858: channel_cancel_rport_listener(const char *host, u_short port)
2859: {
1.209 avsm 2860: u_int i;
2861: int found = 0;
1.202 djm 2862:
1.213 deraadt 2863: for (i = 0; i < channels_alloc; i++) {
1.202 djm 2864: Channel *c = channels[i];
1.312 djm 2865: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
2866: continue;
2867: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
2868: debug2("%s: close channel %d", __func__, i);
2869: channel_free(c);
2870: found = 1;
2871: }
2872: }
2873:
2874: return (found);
2875: }
2876:
2877: int
2878: channel_cancel_lport_listener(const char *lhost, u_short lport,
1.313 markus 2879: int cport, int gateway_ports)
1.312 djm 2880: {
2881: u_int i;
2882: int found = 0;
2883: const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, gateway_ports);
1.202 djm 2884:
1.312 djm 2885: for (i = 0; i < channels_alloc; i++) {
2886: Channel *c = channels[i];
2887: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
2888: continue;
1.313 markus 2889: if (c->listening_port != lport)
1.312 djm 2890: continue;
1.313 markus 2891: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
2892: /* skip dynamic forwardings */
2893: if (c->host_port == 0)
2894: continue;
2895: } else {
2896: if (c->host_port != cport)
2897: continue;
2898: }
1.312 djm 2899: if ((c->listening_addr == NULL && addr != NULL) ||
2900: (c->listening_addr != NULL && addr == NULL))
2901: continue;
2902: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 2903: debug2("%s: close channel %d", __func__, i);
1.202 djm 2904: channel_free(c);
2905: found = 1;
2906: }
2907: }
2908:
2909: return (found);
2910: }
2911:
1.160 markus 2912: /* protocol local port fwd, used by ssh (and sshd in v1) */
2913: int
1.212 djm 2914: channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
1.160 markus 2915: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2916: {
2917: return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
1.295 djm 2918: listen_host, listen_port, NULL, host_to_connect, port_to_connect,
1.212 djm 2919: gateway_ports);
1.160 markus 2920: }
2921:
2922: /* protocol v2 remote port fwd, used by sshd */
2923: int
2924: channel_setup_remote_fwd_listener(const char *listen_address,
1.295 djm 2925: u_short listen_port, int *allocated_listen_port, int gateway_ports)
1.160 markus 2926: {
2927: return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
1.295 djm 2928: listen_address, listen_port, allocated_listen_port,
2929: NULL, 0, gateway_ports);
1.160 markus 2930: }
2931:
1.27 markus 2932: /*
1.312 djm 2933: * Translate the requested rfwd listen host to something usable for
2934: * this server.
2935: */
2936: static const char *
2937: channel_rfwd_bind_host(const char *listen_host)
2938: {
2939: if (listen_host == NULL) {
2940: if (datafellows & SSH_BUG_RFWD_ADDR)
2941: return "127.0.0.1";
2942: else
2943: return "localhost";
2944: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
2945: if (datafellows & SSH_BUG_RFWD_ADDR)
2946: return "0.0.0.0";
2947: else
2948: return "";
2949: } else
2950: return listen_host;
2951: }
2952:
2953: /*
1.27 markus 2954: * Initiate forwarding of connections to port "port" on remote host through
2955: * the secure channel to host:port from local side.
1.315 markus 2956: * Returns handle (index) for updating the dynamic listen port with
2957: * channel_update_permitted_opens().
1.27 markus 2958: */
1.253 markus 2959: int
1.212 djm 2960: channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
1.73 markus 2961: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2962: {
1.315 markus 2963: int type, success = 0, idx = -1;
1.73 markus 2964:
1.25 markus 2965: /* Send the forward request to the remote side. */
1.44 markus 2966: if (compat20) {
2967: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2968: packet_put_cstring("tcpip-forward");
1.312 djm 2969: packet_put_char(1); /* boolean: want reply */
2970: packet_put_cstring(channel_rfwd_bind_host(listen_host));
1.44 markus 2971: packet_put_int(listen_port);
1.73 markus 2972: packet_send();
2973: packet_write_wait();
2974: /* Assume that server accepts the request */
2975: success = 1;
1.44 markus 2976: } else {
2977: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2978: packet_put_int(listen_port);
2979: packet_put_cstring(host_to_connect);
1.44 markus 2980: packet_put_int(port_to_connect);
2981: packet_send();
2982: packet_write_wait();
1.73 markus 2983:
2984: /* Wait for response from the remote side. */
1.153 markus 2985: type = packet_read();
1.73 markus 2986: switch (type) {
2987: case SSH_SMSG_SUCCESS:
2988: success = 1;
2989: break;
2990: case SSH_SMSG_FAILURE:
2991: break;
2992: default:
2993: /* Unknown packet */
2994: packet_disconnect("Protocol error for port forward request:"
2995: "received packet type %d.", type);
2996: }
2997: }
2998: if (success) {
1.305 djm 2999: /* Record that connection to this host/port is permitted. */
3000: permitted_opens = xrealloc(permitted_opens,
3001: num_permitted_opens + 1, sizeof(*permitted_opens));
1.315 markus 3002: idx = num_permitted_opens++;
3003: permitted_opens[idx].host_to_connect = xstrdup(host_to_connect);
3004: permitted_opens[idx].port_to_connect = port_to_connect;
1.333 ! markus 3005: permitted_opens[idx].listen_host = listen_host ?
! 3006: xstrdup(listen_host) : NULL;
1.315 markus 3007: permitted_opens[idx].listen_port = listen_port;
1.44 markus 3008: }
1.315 markus 3009: return (idx);
1.1 deraadt 3010: }
3011:
1.333 ! markus 3012: static int
! 3013: open_match(ForwardPermission *allowed_open, const char *requestedhost,
! 3014: u_short requestedport)
! 3015: {
! 3016: if (allowed_open->host_to_connect == NULL)
! 3017: return 0;
! 3018: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
! 3019: allowed_open->port_to_connect != requestedport)
! 3020: return 0;
! 3021: if (strcmp(allowed_open->host_to_connect, requestedhost) != 0)
! 3022: return 0;
! 3023: return 1;
! 3024: }
! 3025:
! 3026: /*
! 3027: * Note that in he listen host/port case
! 3028: * we don't support FWD_PERMIT_ANY_PORT and
! 3029: * need to translate between the configured-host (listen_host)
! 3030: * and what we've sent to the remote server (channel_rfwd_bind_host)
! 3031: */
! 3032: static int
! 3033: open_listen_match(ForwardPermission *allowed_open, const char *requestedhost,
! 3034: u_short requestedport, int translate)
! 3035: {
! 3036: const char *allowed_host;
! 3037:
! 3038: if (allowed_open->host_to_connect == NULL)
! 3039: return 0;
! 3040: if (allowed_open->listen_port != requestedport)
! 3041: return 0;
! 3042: allowed_host = translate ?
! 3043: channel_rfwd_bind_host(allowed_open->listen_host) :
! 3044: allowed_open->listen_host;
! 3045: if (allowed_host == NULL ||
! 3046: strcmp(allowed_host, requestedhost) != 0)
! 3047: return 0;
! 3048: return 1;
! 3049: }
! 3050:
1.27 markus 3051: /*
1.208 deraadt 3052: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3053: * local side.
3054: */
1.312 djm 3055: int
1.212 djm 3056: channel_request_rforward_cancel(const char *host, u_short port)
1.202 djm 3057: {
3058: int i;
3059:
3060: if (!compat20)
1.312 djm 3061: return -1;
1.202 djm 3062:
3063: for (i = 0; i < num_permitted_opens; i++) {
1.333 ! markus 3064: if (open_listen_match(&permitted_opens[i], host, port, 0))
1.202 djm 3065: break;
3066: }
3067: if (i >= num_permitted_opens) {
3068: debug("%s: requested forward not found", __func__);
1.312 djm 3069: return -1;
1.202 djm 3070: }
3071: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3072: packet_put_cstring("cancel-tcpip-forward");
3073: packet_put_char(0);
1.312 djm 3074: packet_put_cstring(channel_rfwd_bind_host(host));
1.202 djm 3075: packet_put_int(port);
3076: packet_send();
3077:
1.333 ! markus 3078: permitted_opens[i].port_to_connect = 0;
1.202 djm 3079: permitted_opens[i].listen_port = 0;
1.321 djm 3080: free(permitted_opens[i].host_to_connect);
1.202 djm 3081: permitted_opens[i].host_to_connect = NULL;
1.333 ! markus 3082: free(permitted_opens[i].listen_host);
! 3083: permitted_opens[i].listen_host = NULL;
1.312 djm 3084:
3085: return 0;
1.202 djm 3086: }
3087:
3088: /*
1.27 markus 3089: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
3090: * listening for the port, and sends back a success reply (or disconnect
1.253 markus 3091: * message if there was an error).
1.27 markus 3092: */
1.253 markus 3093: int
1.56 markus 3094: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 3095: {
1.31 markus 3096: u_short port, host_port;
1.253 markus 3097: int success = 0;
1.25 markus 3098: char *hostname;
1.1 deraadt 3099:
1.25 markus 3100: /* Get arguments from the packet. */
3101: port = packet_get_int();
3102: hostname = packet_get_string(NULL);
3103: host_port = packet_get_int();
3104:
1.27 markus 3105: /*
3106: * Check that an unprivileged user is not trying to forward a
3107: * privileged port.
3108: */
1.25 markus 3109: if (port < IPPORT_RESERVED && !is_root)
1.192 markus 3110: packet_disconnect(
3111: "Requested forwarding of port %d but user is not root.",
3112: port);
3113: if (host_port == 0)
3114: packet_disconnect("Dynamic forwarding denied.");
3115:
1.73 markus 3116: /* Initiate forwarding */
1.253 markus 3117: success = channel_setup_local_fwd_listener(NULL, port, hostname,
1.212 djm 3118: host_port, gateway_ports);
1.25 markus 3119:
3120: /* Free the argument string. */
1.321 djm 3121: free(hostname);
1.253 markus 3122:
3123: return (success ? 0 : -1);
1.1 deraadt 3124: }
3125:
1.99 markus 3126: /*
3127: * Permits opening to any host/port if permitted_opens[] is empty. This is
3128: * usually called by the server, because the user could connect to any port
3129: * anyway, and the server has no way to know but to trust the client anyway.
3130: */
3131: void
1.142 itojun 3132: channel_permit_all_opens(void)
1.99 markus 3133: {
3134: if (num_permitted_opens == 0)
3135: all_opens_permitted = 1;
3136: }
3137:
1.101 markus 3138: void
1.99 markus 3139: channel_add_permitted_opens(char *host, int port)
3140: {
3141: debug("allow port forwarding to host %s port %d", host, port);
3142:
1.305 djm 3143: permitted_opens = xrealloc(permitted_opens,
3144: num_permitted_opens + 1, sizeof(*permitted_opens));
1.99 markus 3145: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
3146: permitted_opens[num_permitted_opens].port_to_connect = port;
1.333 ! markus 3147: permitted_opens[num_permitted_opens].listen_host = NULL;
! 3148: permitted_opens[num_permitted_opens].listen_port = 0;
1.99 markus 3149: num_permitted_opens++;
3150:
3151: all_opens_permitted = 0;
1.315 markus 3152: }
3153:
3154: /*
3155: * Update the listen port for a dynamic remote forward, after
3156: * the actual 'newport' has been allocated. If 'newport' < 0 is
3157: * passed then they entry will be invalidated.
3158: */
3159: void
3160: channel_update_permitted_opens(int idx, int newport)
3161: {
3162: if (idx < 0 || idx >= num_permitted_opens) {
3163: debug("channel_update_permitted_opens: index out of range:"
3164: " %d num_permitted_opens %d", idx, num_permitted_opens);
3165: return;
3166: }
3167: debug("%s allowed port %d for forwarding to host %s port %d",
3168: newport > 0 ? "Updating" : "Removing",
3169: newport,
3170: permitted_opens[idx].host_to_connect,
3171: permitted_opens[idx].port_to_connect);
3172: if (newport >= 0) {
3173: permitted_opens[idx].listen_port =
3174: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
3175: } else {
3176: permitted_opens[idx].listen_port = 0;
3177: permitted_opens[idx].port_to_connect = 0;
1.321 djm 3178: free(permitted_opens[idx].host_to_connect);
1.315 markus 3179: permitted_opens[idx].host_to_connect = NULL;
1.333 ! markus 3180: free(permitted_opens[idx].listen_host);
! 3181: permitted_opens[idx].listen_host = NULL;
1.315 markus 3182: }
1.99 markus 3183: }
3184:
1.258 dtucker 3185: int
1.257 dtucker 3186: channel_add_adm_permitted_opens(char *host, int port)
3187: {
1.258 dtucker 3188: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 3189:
1.305 djm 3190: permitted_adm_opens = xrealloc(permitted_adm_opens,
3191: num_adm_permitted_opens + 1, sizeof(*permitted_adm_opens));
1.257 dtucker 3192: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
3193: = xstrdup(host);
3194: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.333 ! markus 3195: permitted_adm_opens[num_adm_permitted_opens].listen_host = NULL;
! 3196: permitted_adm_opens[num_adm_permitted_opens].listen_port = 0;
1.258 dtucker 3197: return ++num_adm_permitted_opens;
1.257 dtucker 3198: }
3199:
3200: void
1.316 dtucker 3201: channel_disable_adm_local_opens(void)
3202: {
1.319 djm 3203: channel_clear_adm_permitted_opens();
3204: permitted_adm_opens = xmalloc(sizeof(*permitted_adm_opens));
3205: permitted_adm_opens[num_adm_permitted_opens].host_to_connect = NULL;
3206: num_adm_permitted_opens = 1;
1.316 dtucker 3207: }
3208:
3209: void
1.99 markus 3210: channel_clear_permitted_opens(void)
3211: {
3212: int i;
3213:
1.333 ! markus 3214: for (i = 0; i < num_permitted_opens; i++) {
1.321 djm 3215: free(permitted_opens[i].host_to_connect);
1.333 ! markus 3216: free(permitted_opens[i].listen_host);
! 3217: }
1.321 djm 3218: free(permitted_opens);
3219: permitted_opens = NULL;
1.99 markus 3220: num_permitted_opens = 0;
1.257 dtucker 3221: }
3222:
3223: void
3224: channel_clear_adm_permitted_opens(void)
3225: {
3226: int i;
1.99 markus 3227:
1.333 ! markus 3228: for (i = 0; i < num_adm_permitted_opens; i++) {
1.321 djm 3229: free(permitted_adm_opens[i].host_to_connect);
1.333 ! markus 3230: free(permitted_adm_opens[i].listen_host);
! 3231: }
1.321 djm 3232: free(permitted_adm_opens);
3233: permitted_adm_opens = NULL;
1.257 dtucker 3234: num_adm_permitted_opens = 0;
1.278 dtucker 3235: }
3236:
3237: void
3238: channel_print_adm_permitted_opens(void)
3239: {
1.286 djm 3240: int i;
1.278 dtucker 3241:
1.290 stevesk 3242: printf("permitopen");
1.288 stevesk 3243: if (num_adm_permitted_opens == 0) {
1.290 stevesk 3244: printf(" any\n");
1.288 stevesk 3245: return;
3246: }
1.278 dtucker 3247: for (i = 0; i < num_adm_permitted_opens; i++)
1.316 dtucker 3248: if (permitted_adm_opens[i].host_to_connect == NULL)
3249: printf(" none");
3250: else
1.278 dtucker 3251: printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
3252: permitted_adm_opens[i].port_to_connect);
1.290 stevesk 3253: printf("\n");
1.99 markus 3254: }
3255:
1.314 dtucker 3256: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3257: int
3258: permitopen_port(const char *p)
3259: {
3260: int port;
3261:
3262: if (strcmp(p, "*") == 0)
3263: return FWD_PERMIT_ANY_PORT;
3264: if ((port = a2port(p)) > 0)
3265: return port;
3266: return -1;
3267: }
3268:
1.276 djm 3269: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 3270: static int
1.276 djm 3271: connect_next(struct channel_connect *cctx)
1.41 markus 3272: {
1.276 djm 3273: int sock, saved_errno;
1.41 markus 3274: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
3275:
1.276 djm 3276: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
3277: if (cctx->ai->ai_family != AF_INET &&
3278: cctx->ai->ai_family != AF_INET6)
1.41 markus 3279: continue;
1.276 djm 3280: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
3281: ntop, sizeof(ntop), strport, sizeof(strport),
3282: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
3283: error("connect_next: getnameinfo failed");
1.41 markus 3284: continue;
3285: }
1.300 dtucker 3286: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
3287: cctx->ai->ai_protocol)) == -1) {
1.276 djm 3288: if (cctx->ai->ai_next == NULL)
1.186 djm 3289: error("socket: %.100s", strerror(errno));
3290: else
3291: verbose("socket: %.100s", strerror(errno));
1.41 markus 3292: continue;
3293: }
1.205 djm 3294: if (set_nonblock(sock) == -1)
3295: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 3296: if (connect(sock, cctx->ai->ai_addr,
3297: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
3298: debug("connect_next: host %.100s ([%.100s]:%s): "
3299: "%.100s", cctx->host, ntop, strport,
1.41 markus 3300: strerror(errno));
1.276 djm 3301: saved_errno = errno;
1.41 markus 3302: close(sock);
1.276 djm 3303: errno = saved_errno;
1.89 stevesk 3304: continue; /* fail -- try next */
1.41 markus 3305: }
1.276 djm 3306: debug("connect_next: host %.100s ([%.100s]:%s) "
3307: "in progress, fd=%d", cctx->host, ntop, strport, sock);
3308: cctx->ai = cctx->ai->ai_next;
3309: set_nodelay(sock);
3310: return sock;
3311: }
3312: return -1;
3313: }
1.41 markus 3314:
1.276 djm 3315: static void
3316: channel_connect_ctx_free(struct channel_connect *cctx)
3317: {
1.321 djm 3318: free(cctx->host);
1.276 djm 3319: if (cctx->aitop)
3320: freeaddrinfo(cctx->aitop);
1.329 tedu 3321: memset(cctx, 0, sizeof(*cctx));
1.276 djm 3322: }
3323:
3324: /* Return CONNECTING channel to remote host, port */
3325: static Channel *
3326: connect_to(const char *host, u_short port, char *ctype, char *rname)
3327: {
3328: struct addrinfo hints;
3329: int gaierr;
3330: int sock = -1;
3331: char strport[NI_MAXSERV];
3332: struct channel_connect cctx;
3333: Channel *c;
3334:
1.284 djm 3335: memset(&cctx, 0, sizeof(cctx));
1.276 djm 3336: memset(&hints, 0, sizeof(hints));
3337: hints.ai_family = IPv4or6;
3338: hints.ai_socktype = SOCK_STREAM;
3339: snprintf(strport, sizeof strport, "%d", port);
3340: if ((gaierr = getaddrinfo(host, strport, &hints, &cctx.aitop)) != 0) {
3341: error("connect_to %.100s: unknown host (%s)", host,
3342: ssh_gai_strerror(gaierr));
3343: return NULL;
1.41 markus 3344: }
1.276 djm 3345:
3346: cctx.host = xstrdup(host);
3347: cctx.port = port;
3348: cctx.ai = cctx.aitop;
3349:
3350: if ((sock = connect_next(&cctx)) == -1) {
3351: error("connect to %.100s port %d failed: %s",
3352: host, port, strerror(errno));
3353: channel_connect_ctx_free(&cctx);
3354: return NULL;
1.41 markus 3355: }
1.276 djm 3356: c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
3357: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
3358: c->connect_ctx = cctx;
3359: return c;
1.41 markus 3360: }
1.99 markus 3361:
1.276 djm 3362: Channel *
1.333 ! markus 3363: channel_connect_by_listen_address(const char *listen_host,
! 3364: u_short listen_port, char *ctype, char *rname)
1.73 markus 3365: {
3366: int i;
1.99 markus 3367:
1.276 djm 3368: for (i = 0; i < num_permitted_opens; i++) {
1.333 ! markus 3369: if (open_listen_match(&permitted_opens[i], listen_host,
! 3370: listen_port, 1)) {
1.99 markus 3371: return connect_to(
1.73 markus 3372: permitted_opens[i].host_to_connect,
1.276 djm 3373: permitted_opens[i].port_to_connect, ctype, rname);
3374: }
3375: }
1.74 markus 3376: error("WARNING: Server requests forwarding for unknown listen_port %d",
3377: listen_port);
1.276 djm 3378: return NULL;
1.73 markus 3379: }
3380:
1.99 markus 3381: /* Check if connecting to that port is permitted and connect. */
1.276 djm 3382: Channel *
3383: channel_connect_to(const char *host, u_short port, char *ctype, char *rname)
1.99 markus 3384: {
1.257 dtucker 3385: int i, permit, permit_adm = 1;
1.99 markus 3386:
3387: permit = all_opens_permitted;
3388: if (!permit) {
3389: for (i = 0; i < num_permitted_opens; i++)
1.333 ! markus 3390: if (open_match(&permitted_opens[i], host, port)) {
1.99 markus 3391: permit = 1;
1.333 ! markus 3392: break;
! 3393: }
1.257 dtucker 3394: }
1.99 markus 3395:
1.257 dtucker 3396: if (num_adm_permitted_opens > 0) {
3397: permit_adm = 0;
3398: for (i = 0; i < num_adm_permitted_opens; i++)
1.333 ! markus 3399: if (open_match(&permitted_adm_opens[i], host, port)) {
1.257 dtucker 3400: permit_adm = 1;
1.333 ! markus 3401: break;
! 3402: }
1.99 markus 3403: }
1.257 dtucker 3404:
3405: if (!permit || !permit_adm) {
1.188 itojun 3406: logit("Received request to connect to host %.100s port %d, "
1.99 markus 3407: "but the request was denied.", host, port);
1.276 djm 3408: return NULL;
1.99 markus 3409: }
1.276 djm 3410: return connect_to(host, port, ctype, rname);
1.204 djm 3411: }
3412:
3413: void
3414: channel_send_window_changes(void)
3415: {
1.209 avsm 3416: u_int i;
1.204 djm 3417: struct winsize ws;
3418:
3419: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 3420: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 3421: channels[i]->type != SSH_CHANNEL_OPEN)
3422: continue;
3423: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
3424: continue;
3425: channel_request_start(i, "window-change", 0);
1.238 deraadt 3426: packet_put_int((u_int)ws.ws_col);
3427: packet_put_int((u_int)ws.ws_row);
3428: packet_put_int((u_int)ws.ws_xpixel);
3429: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 3430: packet_send();
3431: }
1.99 markus 3432: }
3433:
1.121 markus 3434: /* -- X11 forwarding */
1.1 deraadt 3435:
1.27 markus 3436: /*
3437: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 3438: * Returns 0 and a suitable display number for the DISPLAY variable
3439: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 3440: */
1.141 stevesk 3441: int
1.163 stevesk 3442: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 3443: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 3444: {
1.149 markus 3445: Channel *nc = NULL;
1.31 markus 3446: int display_number, sock;
3447: u_short port;
1.35 markus 3448: struct addrinfo hints, *ai, *aitop;
3449: char strport[NI_MAXSERV];
3450: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 3451:
1.224 markus 3452: if (chanids == NULL)
3453: return -1;
3454:
1.33 markus 3455: for (display_number = x11_display_offset;
1.148 deraadt 3456: display_number < MAX_DISPLAYS;
3457: display_number++) {
1.25 markus 3458: port = 6000 + display_number;
1.35 markus 3459: memset(&hints, 0, sizeof(hints));
3460: hints.ai_family = IPv4or6;
1.163 stevesk 3461: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 3462: hints.ai_socktype = SOCK_STREAM;
3463: snprintf(strport, sizeof strport, "%d", port);
3464: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3465: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 3466: return -1;
1.25 markus 3467: }
1.35 markus 3468: for (ai = aitop; ai; ai = ai->ai_next) {
3469: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
3470: continue;
1.300 dtucker 3471: sock = socket(ai->ai_family, ai->ai_socktype,
3472: ai->ai_protocol);
1.35 markus 3473: if (sock < 0) {
3474: error("socket: %.100s", strerror(errno));
1.203 markus 3475: freeaddrinfo(aitop);
1.141 stevesk 3476: return -1;
1.35 markus 3477: }
1.226 djm 3478: channel_set_reuseaddr(sock);
1.35 markus 3479: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 3480: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 3481: close(sock);
1.183 itojun 3482:
1.35 markus 3483: for (n = 0; n < num_socks; n++) {
3484: close(socks[n]);
3485: }
3486: num_socks = 0;
3487: break;
3488: }
3489: socks[num_socks++] = sock;
3490: if (num_socks == NUM_SOCKS)
3491: break;
1.25 markus 3492: }
1.83 stevesk 3493: freeaddrinfo(aitop);
1.35 markus 3494: if (num_socks > 0)
3495: break;
1.25 markus 3496: }
3497: if (display_number >= MAX_DISPLAYS) {
3498: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 3499: return -1;
1.25 markus 3500: }
3501: /* Start listening for connections on the socket. */
1.35 markus 3502: for (n = 0; n < num_socks; n++) {
3503: sock = socks[n];
1.199 markus 3504: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3505: error("listen: %.100s", strerror(errno));
3506: close(sock);
1.141 stevesk 3507: return -1;
1.35 markus 3508: }
1.25 markus 3509: }
1.35 markus 3510:
3511: /* Allocate a channel for each socket. */
1.242 djm 3512: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 3513: for (n = 0; n < num_socks; n++) {
3514: sock = socks[n];
1.149 markus 3515: nc = channel_new("x11 listener",
1.51 markus 3516: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
3517: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 3518: 0, "X11 inet listener", 1);
1.167 markus 3519: nc->single_connection = single_connection;
1.224 markus 3520: (*chanids)[n] = nc->self;
1.35 markus 3521: }
1.224 markus 3522: (*chanids)[n] = -1;
1.1 deraadt 3523:
1.141 stevesk 3524: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 3525: *display_numberp = display_number;
3526: return (0);
1.1 deraadt 3527: }
3528:
1.127 itojun 3529: static int
1.77 markus 3530: connect_local_xsocket(u_int dnr)
1.1 deraadt 3531: {
1.25 markus 3532: int sock;
3533: struct sockaddr_un addr;
3534:
1.147 stevesk 3535: sock = socket(AF_UNIX, SOCK_STREAM, 0);
3536: if (sock < 0)
3537: error("socket: %.100s", strerror(errno));
3538: memset(&addr, 0, sizeof(addr));
3539: addr.sun_family = AF_UNIX;
3540: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 3541: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 3542: return sock;
3543: close(sock);
1.25 markus 3544: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
3545: return -1;
1.1 deraadt 3546: }
3547:
1.51 markus 3548: int
3549: x11_connect_display(void)
1.1 deraadt 3550: {
1.248 deraadt 3551: u_int display_number;
1.25 markus 3552: const char *display;
1.51 markus 3553: char buf[1024], *cp;
1.35 markus 3554: struct addrinfo hints, *ai, *aitop;
3555: char strport[NI_MAXSERV];
1.248 deraadt 3556: int gaierr, sock = 0;
1.25 markus 3557:
3558: /* Try to open a socket for the local X server. */
3559: display = getenv("DISPLAY");
3560: if (!display) {
3561: error("DISPLAY not set.");
1.51 markus 3562: return -1;
1.25 markus 3563: }
1.27 markus 3564: /*
3565: * Now we decode the value of the DISPLAY variable and make a
3566: * connection to the real X server.
3567: */
3568:
3569: /*
3570: * Check if it is a unix domain socket. Unix domain displays are in
3571: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3572: */
1.25 markus 3573: if (strncmp(display, "unix:", 5) == 0 ||
3574: display[0] == ':') {
3575: /* Connect to the unix domain socket. */
1.248 deraadt 3576: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 3577: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3578: display);
1.51 markus 3579: return -1;
1.25 markus 3580: }
3581: /* Create a socket. */
3582: sock = connect_local_xsocket(display_number);
3583: if (sock < 0)
1.51 markus 3584: return -1;
1.25 markus 3585:
3586: /* OK, we now have a connection to the display. */
1.51 markus 3587: return sock;
1.25 markus 3588: }
1.27 markus 3589: /*
3590: * Connect to an inet socket. The DISPLAY value is supposedly
3591: * hostname:d[.s], where hostname may also be numeric IP address.
3592: */
1.145 stevesk 3593: strlcpy(buf, display, sizeof(buf));
1.25 markus 3594: cp = strchr(buf, ':');
3595: if (!cp) {
3596: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 3597: return -1;
1.25 markus 3598: }
3599: *cp = 0;
1.27 markus 3600: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 3601: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 3602: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3603: display);
1.51 markus 3604: return -1;
1.25 markus 3605: }
1.35 markus 3606:
3607: /* Look up the host address */
3608: memset(&hints, 0, sizeof(hints));
3609: hints.ai_family = IPv4or6;
3610: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 3611: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 3612: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3613: error("%.100s: unknown host. (%s)", buf,
3614: ssh_gai_strerror(gaierr));
1.51 markus 3615: return -1;
1.25 markus 3616: }
1.35 markus 3617: for (ai = aitop; ai; ai = ai->ai_next) {
3618: /* Create a socket. */
1.300 dtucker 3619: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 3620: if (sock < 0) {
1.194 markus 3621: debug2("socket: %.100s", strerror(errno));
1.41 markus 3622: continue;
3623: }
3624: /* Connect it to the display. */
3625: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 3626: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 3627: 6000 + display_number, strerror(errno));
3628: close(sock);
3629: continue;
3630: }
3631: /* Success */
3632: break;
1.35 markus 3633: }
3634: freeaddrinfo(aitop);
3635: if (!ai) {
1.248 deraadt 3636: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 3637: strerror(errno));
1.51 markus 3638: return -1;
1.25 markus 3639: }
1.162 stevesk 3640: set_nodelay(sock);
1.51 markus 3641: return sock;
3642: }
3643:
3644: /*
3645: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
3646: * the remote channel number. We should do whatever we want, and respond
3647: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
3648: */
3649:
1.259 stevesk 3650: /* ARGSUSED */
1.51 markus 3651: void
1.154 markus 3652: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 3653: {
1.113 markus 3654: Channel *c = NULL;
3655: int remote_id, sock = 0;
1.51 markus 3656: char *remote_host;
1.25 markus 3657:
1.113 markus 3658: debug("Received X11 open request.");
1.51 markus 3659:
1.113 markus 3660: remote_id = packet_get_int();
1.121 markus 3661:
3662: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 3663: remote_host = packet_get_string(NULL);
1.51 markus 3664: } else {
3665: remote_host = xstrdup("unknown (remote did not supply name)");
3666: }
1.152 markus 3667: packet_check_eom();
1.25 markus 3668:
1.51 markus 3669: /* Obtain a connection to the real X display. */
3670: sock = x11_connect_display();
1.113 markus 3671: if (sock != -1) {
3672: /* Allocate a channel for this connection. */
3673: c = channel_new("connected x11 socket",
3674: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
3675: remote_host, 1);
1.167 markus 3676: c->remote_id = remote_id;
3677: c->force_drain = 1;
1.113 markus 3678: }
1.321 djm 3679: free(remote_host);
1.113 markus 3680: if (c == NULL) {
1.51 markus 3681: /* Send refusal to the remote host. */
3682: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 3683: packet_put_int(remote_id);
1.51 markus 3684: } else {
3685: /* Send a confirmation to the remote host. */
3686: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 3687: packet_put_int(remote_id);
3688: packet_put_int(c->self);
1.51 markus 3689: }
1.113 markus 3690: packet_send();
1.72 markus 3691: }
3692:
3693: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
1.259 stevesk 3694: /* ARGSUSED */
1.72 markus 3695: void
1.154 markus 3696: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 3697: {
3698: int rchan = packet_get_int();
1.180 deraadt 3699:
1.143 deraadt 3700: switch (type) {
1.72 markus 3701: case SSH_SMSG_AGENT_OPEN:
3702: error("Warning: ssh server tried agent forwarding.");
3703: break;
3704: case SSH_SMSG_X11_OPEN:
3705: error("Warning: ssh server tried X11 forwarding.");
3706: break;
3707: default:
1.154 markus 3708: error("deny_input_open: type %d", type);
1.72 markus 3709: break;
3710: }
1.230 stevesk 3711: error("Warning: this is probably a break-in attempt by a malicious server.");
1.72 markus 3712: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
3713: packet_put_int(rchan);
3714: packet_send();
1.1 deraadt 3715: }
3716:
1.27 markus 3717: /*
3718: * Requests forwarding of X11 connections, generates fake authentication
3719: * data, and enables authentication spoofing.
1.121 markus 3720: * This should be called in the client only.
1.27 markus 3721: */
1.49 markus 3722: void
1.215 djm 3723: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.311 djm 3724: const char *proto, const char *data, int want_reply)
1.1 deraadt 3725: {
1.77 markus 3726: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 3727: u_int i, value;
1.25 markus 3728: char *new_data;
3729: int screen_number;
3730: const char *cp;
1.207 avsm 3731: u_int32_t rnd = 0;
1.25 markus 3732:
1.220 markus 3733: if (x11_saved_display == NULL)
3734: x11_saved_display = xstrdup(disp);
3735: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 3736: error("x11_request_forwarding_with_spoofing: different "
3737: "$DISPLAY already forwarded");
3738: return;
3739: }
3740:
1.266 djm 3741: cp = strchr(disp, ':');
1.25 markus 3742: if (cp)
3743: cp = strchr(cp, '.');
3744: if (cp)
1.245 deraadt 3745: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 3746: else
3747: screen_number = 0;
3748:
1.219 djm 3749: if (x11_saved_proto == NULL) {
3750: /* Save protocol name. */
3751: x11_saved_proto = xstrdup(proto);
3752: /*
1.221 djm 3753: * Extract real authentication data and generate fake data
1.219 djm 3754: * of the same length.
3755: */
3756: x11_saved_data = xmalloc(data_len);
3757: x11_fake_data = xmalloc(data_len);
3758: for (i = 0; i < data_len; i++) {
3759: if (sscanf(data + 2 * i, "%2x", &value) != 1)
3760: fatal("x11_request_forwarding: bad "
3761: "authentication data: %.100s", data);
3762: if (i % 4 == 0)
3763: rnd = arc4random();
3764: x11_saved_data[i] = value;
3765: x11_fake_data[i] = rnd & 0xff;
3766: rnd >>= 8;
3767: }
3768: x11_saved_data_len = data_len;
3769: x11_fake_data_len = data_len;
1.25 markus 3770: }
3771:
3772: /* Convert the fake data into hex. */
1.219 djm 3773: new_data = tohex(x11_fake_data, data_len);
1.25 markus 3774:
3775: /* Send the request packet. */
1.51 markus 3776: if (compat20) {
1.311 djm 3777: channel_request_start(client_session_id, "x11-req", want_reply);
1.51 markus 3778: packet_put_char(0); /* XXX bool single connection */
3779: } else {
3780: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
3781: }
3782: packet_put_cstring(proto);
3783: packet_put_cstring(new_data);
1.25 markus 3784: packet_put_int(screen_number);
3785: packet_send();
3786: packet_write_wait();
1.321 djm 3787: free(new_data);
1.1 deraadt 3788: }
3789:
1.121 markus 3790:
3791: /* -- agent forwarding */
3792:
1.1 deraadt 3793: /* Sends a message to the server to request authentication fd forwarding. */
3794:
1.49 markus 3795: void
1.142 itojun 3796: auth_request_forwarding(void)
1.1 deraadt 3797: {
1.25 markus 3798: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
3799: packet_send();
3800: packet_write_wait();
1.1 deraadt 3801: }
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