Annotation of src/usr.bin/ssh/channels.c, Revision 1.438
1.438 ! djm 1: /* $OpenBSD: channels.c,v 1.437 2024/03/06 02:59:59 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>
1.336 millert 43: #include <sys/stat.h>
1.234 stevesk 44: #include <sys/ioctl.h>
1.235 stevesk 45: #include <sys/un.h>
1.251 stevesk 46: #include <sys/socket.h>
1.261 stevesk 47: #include <sys/time.h>
1.275 djm 48: #include <sys/queue.h>
1.251 stevesk 49:
50: #include <netinet/in.h>
51: #include <arpa/inet.h>
1.233 stevesk 52:
1.254 stevesk 53: #include <errno.h>
1.298 dtucker 54: #include <fcntl.h>
1.367 djm 55: #include <limits.h>
1.255 stevesk 56: #include <netdb.h>
1.411 djm 57: #include <poll.h>
1.367 djm 58: #include <stdarg.h>
1.341 millert 59: #include <stdint.h>
1.263 stevesk 60: #include <stdio.h>
1.262 stevesk 61: #include <stdlib.h>
1.260 stevesk 62: #include <string.h>
1.233 stevesk 63: #include <termios.h>
1.256 stevesk 64: #include <unistd.h>
1.1 deraadt 65:
1.265 deraadt 66: #include "xmalloc.h"
1.1 deraadt 67: #include "ssh.h"
1.82 markus 68: #include "ssh2.h"
1.354 markus 69: #include "ssherr.h"
1.367 djm 70: #include "sshbuf.h"
1.1 deraadt 71: #include "packet.h"
1.82 markus 72: #include "log.h"
73: #include "misc.h"
1.14 markus 74: #include "channels.h"
75: #include "compat.h"
1.82 markus 76: #include "canohost.h"
1.383 markus 77: #include "sshkey.h"
1.64 markus 78: #include "authfd.h"
1.147 stevesk 79: #include "pathnames.h"
1.381 djm 80: #include "match.h"
1.388 djm 81:
1.411 djm 82: /* XXX remove once we're satisfied there's no lurking bugs */
83: /* #define DEBUG_CHANNEL_POLL 1 */
84:
1.367 djm 85: /* -- agent forwarding */
86: #define NUM_SOCKS 10
1.12 markus 87:
1.367 djm 88: /* -- X11 forwarding */
89: /* Maximum number of fake X11 displays to try. */
90: #define MAX_DISPLAYS 1000
1.1 deraadt 91:
1.411 djm 92: /* Per-channel callback for pre/post IO actions */
1.410 djm 93: typedef void chan_fn(struct ssh *, Channel *c);
1.381 djm 94:
1.27 markus 95: /*
96: * Data structure for storing which hosts are permitted for forward requests.
97: * The local sides of any remote forwards are stored in this array to prevent
98: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
99: * network (which might be behind a firewall).
100: */
1.336 millert 101: /* XXX: streamlocal wants a path instead of host:port */
102: /* Overload host_to_connect; we could just make this match Forward */
103: /* XXX - can we use listen_host instead of listen_path? */
1.381 djm 104: struct permission {
1.41 markus 105: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 106: int port_to_connect; /* Connect to 'port'. */
1.333 markus 107: char *listen_host; /* Remote side should listen address. */
1.336 millert 108: char *listen_path; /* Remote side should listen path. */
109: int listen_port; /* Remote side should listen port. */
1.354 markus 110: Channel *downstream; /* Downstream mux*/
1.381 djm 111: };
112:
113: /*
114: * Stores the forwarding permission state for a single direction (local or
115: * remote).
116: */
117: struct permission_set {
118: /*
119: * List of all local permitted host/port pairs to allow for the
120: * user.
121: */
122: u_int num_permitted_user;
123: struct permission *permitted_user;
1.1 deraadt 124:
1.381 djm 125: /*
126: * List of all permitted host/port pairs to allow for the admin.
127: */
128: u_int num_permitted_admin;
129: struct permission *permitted_admin;
130:
131: /*
132: * If this is true, all opens/listens are permitted. This is the
133: * case on the server on which we have to trust the client anyway,
134: * and the user could do anything after logging in.
135: */
136: int all_permitted;
137: };
1.121 markus 138:
1.426 djm 139: /* Used to record timeouts per channel type */
140: struct ssh_channel_timeout {
141: char *type_pattern;
1.431 millert 142: int timeout_secs;
1.426 djm 143: };
144:
1.367 djm 145: /* Master structure for channels state */
146: struct ssh_channels {
147: /*
148: * Pointer to an array containing all allocated channels. The array
149: * is dynamically extended as needed.
150: */
151: Channel **channels;
1.257 dtucker 152:
1.367 djm 153: /*
154: * Size of the channel array. All slots of the array must always be
155: * initialized (at least the type field); unused slots set to NULL
156: */
157: u_int channels_alloc;
1.257 dtucker 158:
1.367 djm 159: /*
1.411 djm 160: * 'channel_pre*' are called just before IO to add any bits
161: * relevant to channels in the c->io_want bitmasks.
1.367 djm 162: *
163: * 'channel_post*': perform any appropriate operations for
1.411 djm 164: * channels which have c->io_ready events pending.
1.367 djm 165: */
166: chan_fn **channel_pre;
167: chan_fn **channel_post;
1.314 dtucker 168:
1.367 djm 169: /* -- tcp forwarding */
1.381 djm 170: struct permission_set local_perms;
171: struct permission_set remote_perms;
1.219 djm 172:
1.367 djm 173: /* -- X11 forwarding */
1.121 markus 174:
1.367 djm 175: /* Saved X11 local (client) display. */
176: char *x11_saved_display;
1.121 markus 177:
1.367 djm 178: /* Saved X11 authentication protocol name. */
179: char *x11_saved_proto;
1.347 djm 180:
1.367 djm 181: /* Saved X11 authentication data. This is the real data. */
182: char *x11_saved_data;
183: u_int x11_saved_data_len;
1.121 markus 184:
1.367 djm 185: /* Deadline after which all X11 connections are refused */
1.428 dtucker 186: time_t x11_refuse_time;
1.121 markus 187:
1.367 djm 188: /*
189: * Fake X11 authentication data. This is what the server will be
190: * sending us; we should replace any occurrences of this by the
191: * real data.
192: */
193: u_char *x11_fake_data;
194: u_int x11_fake_data_len;
1.121 markus 195:
1.367 djm 196: /* AF_UNSPEC or AF_INET or AF_INET6 */
197: int IPv4or6;
1.426 djm 198:
199: /* Channel timeouts by type */
200: struct ssh_channel_timeout *timeouts;
201: size_t ntimeouts;
1.436 djm 202: /* Global timeout for all OPEN channels */
203: int global_deadline;
204: time_t lastused;
1.367 djm 205: };
1.1 deraadt 206:
1.121 markus 207: /* helper */
1.367 djm 208: static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
1.354 markus 209: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 210:
1.276 djm 211: /* non-blocking connect helpers */
212: static int connect_next(struct channel_connect *);
213: static void channel_connect_ctx_free(struct channel_connect *);
1.372 markus 214: static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
215: static int rdynamic_connect_finish(struct ssh *, Channel *);
1.276 djm 216:
1.367 djm 217: /* Setup helper */
218: static void channel_handler_init(struct ssh_channels *sc);
219:
1.121 markus 220: /* -- channel core */
1.41 markus 221:
1.367 djm 222: void
223: channel_init_channels(struct ssh *ssh)
224: {
225: struct ssh_channels *sc;
226:
1.387 djm 227: if ((sc = calloc(1, sizeof(*sc))) == NULL)
1.403 djm 228: fatal_f("allocation failed");
1.367 djm 229: sc->channels_alloc = 10;
230: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
231: sc->IPv4or6 = AF_UNSPEC;
232: channel_handler_init(sc);
233:
234: ssh->chanctxt = sc;
235: }
236:
1.41 markus 237: Channel *
1.367 djm 238: channel_by_id(struct ssh *ssh, int id)
1.41 markus 239: {
240: Channel *c;
1.113 markus 241:
1.367 djm 242: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
1.403 djm 243: logit_f("%d: bad id", id);
1.41 markus 244: return NULL;
245: }
1.367 djm 246: c = ssh->chanctxt->channels[id];
1.113 markus 247: if (c == NULL) {
1.403 djm 248: logit_f("%d: bad id: channel free", id);
1.41 markus 249: return NULL;
250: }
251: return c;
1.55 markus 252: }
253:
1.354 markus 254: Channel *
1.368 djm 255: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 256: {
257: Channel *c;
258: u_int i;
259:
1.367 djm 260: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
261: c = ssh->chanctxt->channels[i];
1.368 djm 262: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 263: return c;
264: }
265: return NULL;
266: }
267:
1.27 markus 268: /*
1.229 markus 269: * Returns the channel if it is allowed to receive protocol messages.
270: * Private channels, like listening sockets, may not receive messages.
271: */
272: Channel *
1.367 djm 273: channel_lookup(struct ssh *ssh, int id)
1.229 markus 274: {
275: Channel *c;
276:
1.367 djm 277: if ((c = channel_by_id(ssh, id)) == NULL)
278: return NULL;
1.229 markus 279:
1.237 deraadt 280: switch (c->type) {
1.229 markus 281: case SSH_CHANNEL_X11_OPEN:
282: case SSH_CHANNEL_LARVAL:
283: case SSH_CHANNEL_CONNECTING:
284: case SSH_CHANNEL_DYNAMIC:
1.372 markus 285: case SSH_CHANNEL_RDYNAMIC_OPEN:
286: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 287: case SSH_CHANNEL_OPENING:
288: case SSH_CHANNEL_OPEN:
1.323 dtucker 289: case SSH_CHANNEL_ABANDONED:
1.354 markus 290: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 291: return c;
1.229 markus 292: }
293: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 294: return NULL;
1.229 markus 295: }
296:
297: /*
1.426 djm 298: * Add a timeout for open channels whose c->ctype (or c->xctype if it is set)
299: * match type_pattern.
300: */
301: void
302: channel_add_timeout(struct ssh *ssh, const char *type_pattern,
1.431 millert 303: int timeout_secs)
1.426 djm 304: {
305: struct ssh_channels *sc = ssh->chanctxt;
306:
1.436 djm 307: if (strcmp(type_pattern, "global") == 0) {
308: debug2_f("global channel timeout %d seconds", timeout_secs);
309: sc->global_deadline = timeout_secs;
310: return;
311: }
1.431 millert 312: debug2_f("channel type \"%s\" timeout %d seconds",
1.426 djm 313: type_pattern, timeout_secs);
314: sc->timeouts = xrecallocarray(sc->timeouts, sc->ntimeouts,
315: sc->ntimeouts + 1, sizeof(*sc->timeouts));
316: sc->timeouts[sc->ntimeouts].type_pattern = xstrdup(type_pattern);
317: sc->timeouts[sc->ntimeouts].timeout_secs = timeout_secs;
318: sc->ntimeouts++;
319: }
320:
321: /* Clears all previously-added channel timeouts */
322: void
323: channel_clear_timeouts(struct ssh *ssh)
324: {
325: struct ssh_channels *sc = ssh->chanctxt;
326: size_t i;
327:
328: debug3_f("clearing");
329: for (i = 0; i < sc->ntimeouts; i++)
330: free(sc->timeouts[i].type_pattern);
331: free(sc->timeouts);
332: sc->timeouts = NULL;
333: sc->ntimeouts = 0;
334: }
335:
1.431 millert 336: static int
1.426 djm 337: lookup_timeout(struct ssh *ssh, const char *type)
338: {
339: struct ssh_channels *sc = ssh->chanctxt;
340: size_t i;
341:
342: for (i = 0; i < sc->ntimeouts; i++) {
343: if (match_pattern(type, sc->timeouts[i].type_pattern))
344: return sc->timeouts[i].timeout_secs;
345: }
346:
347: return 0;
348: }
349:
350: /*
1.425 djm 351: * Sets "extended type" of a channel; used by session layer to add additional
352: * information about channel types (e.g. shell, login, subsystem) that can then
353: * be used to select timeouts.
1.426 djm 354: * Will reset c->inactive_deadline as a side-effect.
1.425 djm 355: */
356: void
357: channel_set_xtype(struct ssh *ssh, int id, const char *xctype)
358: {
359: Channel *c;
360:
361: if ((c = channel_by_id(ssh, id)) == NULL)
362: fatal_f("missing channel %d", id);
363: if (c->xctype != NULL)
364: free(c->xctype);
365: c->xctype = xstrdup(xctype);
1.426 djm 366: /* Type has changed, so look up inactivity deadline again */
367: c->inactive_deadline = lookup_timeout(ssh, c->xctype);
368: debug2_f("labeled channel %d as %s (inactive timeout %u)", id, xctype,
369: c->inactive_deadline);
1.425 djm 370: }
371:
372: /*
1.436 djm 373: * update "last used" time on a channel.
374: * NB. nothing else should update lastused except to clear it.
375: */
376: static void
377: channel_set_used_time(struct ssh *ssh, Channel *c)
378: {
379: ssh->chanctxt->lastused = monotime();
380: if (c != NULL)
381: c->lastused = ssh->chanctxt->lastused;
382: }
383:
384: /*
385: * Get the time at which a channel is due to time out for inactivity.
386: * Returns 0 if the channel is not due to time out ever.
387: */
388: static time_t
389: channel_get_expiry(struct ssh *ssh, Channel *c)
390: {
391: struct ssh_channels *sc = ssh->chanctxt;
392: time_t expiry = 0, channel_expiry;
393:
394: if (sc->lastused != 0 && sc->global_deadline != 0)
395: expiry = sc->lastused + sc->global_deadline;
396: if (c->lastused != 0 && c->inactive_deadline != 0) {
397: channel_expiry = c->lastused + c->inactive_deadline;
398: if (expiry == 0 || channel_expiry < expiry)
399: expiry = channel_expiry;
400: }
401: return expiry;
402: }
403:
404: /*
1.55 markus 405: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 406: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 407: */
1.127 itojun 408: static void
1.367 djm 409: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 410: int extusage, int nonblock, int is_tty)
1.1 deraadt 411: {
1.418 markus 412: int val;
413:
1.298 dtucker 414: if (rfd != -1)
1.430 dtucker 415: (void)fcntl(rfd, F_SETFD, FD_CLOEXEC);
1.298 dtucker 416: if (wfd != -1 && wfd != rfd)
1.430 dtucker 417: (void)fcntl(wfd, F_SETFD, FD_CLOEXEC);
1.298 dtucker 418: if (efd != -1 && efd != rfd && efd != wfd)
1.430 dtucker 419: (void)fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 420:
1.52 markus 421: c->rfd = rfd;
422: c->wfd = wfd;
423: c->sock = (rfd == wfd) ? rfd : -1;
424: c->efd = efd;
425: c->extended_usage = extusage;
1.71 markus 426:
1.282 dtucker 427: if ((c->isatty = is_tty) != 0)
1.194 markus 428: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 429:
1.71 markus 430: /* enable nonblocking mode */
1.407 djm 431: c->restore_block = 0;
432: if (nonblock == CHANNEL_NONBLOCK_STDIO) {
433: /*
434: * Special handling for stdio file descriptors: do not set
435: * non-blocking mode if they are TTYs. Otherwise prepare to
436: * restore their blocking state on exit to avoid interfering
437: * with other programs that follow.
438: */
1.418 markus 439: if (rfd != -1 && !isatty(rfd) &&
440: (val = fcntl(rfd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) {
1.427 djm 441: c->restore_flags[0] = val;
1.407 djm 442: c->restore_block |= CHANNEL_RESTORE_RFD;
443: set_nonblock(rfd);
444: }
1.418 markus 445: if (wfd != -1 && !isatty(wfd) &&
446: (val = fcntl(wfd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) {
1.427 djm 447: c->restore_flags[1] = val;
1.407 djm 448: c->restore_block |= CHANNEL_RESTORE_WFD;
449: set_nonblock(wfd);
450: }
1.418 markus 451: if (efd != -1 && !isatty(efd) &&
452: (val = fcntl(efd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) {
1.427 djm 453: c->restore_flags[2] = val;
1.407 djm 454: c->restore_block |= CHANNEL_RESTORE_EFD;
455: set_nonblock(efd);
456: }
457: } else if (nonblock) {
1.71 markus 458: if (rfd != -1)
459: set_nonblock(rfd);
460: if (wfd != -1)
461: set_nonblock(wfd);
462: if (efd != -1)
463: set_nonblock(efd);
464: }
1.436 djm 465: /* channel might be entering a larval state, so reset global timeout */
466: channel_set_used_time(ssh, NULL);
1.52 markus 467: }
468:
469: /*
1.419 djm 470: * Allocate a new channel object and set its type and socket.
1.52 markus 471: */
1.113 markus 472: Channel *
1.367 djm 473: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.419 djm 474: u_int window, u_int maxpack, int extusage, const char *remote_name,
475: int nonblock)
1.52 markus 476: {
1.367 djm 477: struct ssh_channels *sc = ssh->chanctxt;
478: u_int i, found;
1.52 markus 479: Channel *c;
1.402 djm 480: int r;
1.25 markus 481:
482: /* Try to find a free slot where to put the new channel. */
1.367 djm 483: for (i = 0; i < sc->channels_alloc; i++) {
484: if (sc->channels[i] == NULL) {
1.25 markus 485: /* Found a free slot. */
1.367 djm 486: found = i;
1.25 markus 487: break;
488: }
1.367 djm 489: }
490: if (i >= sc->channels_alloc) {
491: /*
492: * There are no free slots. Take last+1 slot and expand
493: * the array.
494: */
495: found = sc->channels_alloc;
496: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
1.403 djm 497: fatal_f("internal error: channels_alloc %d too big",
498: sc->channels_alloc);
1.367 djm 499: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
500: sc->channels_alloc + 10, sizeof(*sc->channels));
501: sc->channels_alloc += 10;
502: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 503: }
1.113 markus 504: /* Initialize and return new channel. */
1.367 djm 505: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
506: if ((c->input = sshbuf_new()) == NULL ||
507: (c->output = sshbuf_new()) == NULL ||
508: (c->extended = sshbuf_new()) == NULL)
1.403 djm 509: fatal_f("sshbuf_new failed");
1.402 djm 510: if ((r = sshbuf_set_max_size(c->input, CHAN_INPUT_MAX)) != 0)
1.403 djm 511: fatal_fr(r, "sshbuf_set_max_size");
1.159 markus 512: c->ostate = CHAN_OUTPUT_OPEN;
513: c->istate = CHAN_INPUT_OPEN;
1.367 djm 514: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 515: c->self = found;
516: c->type = type;
1.41 markus 517: c->ctype = ctype;
1.51 markus 518: c->local_window = window;
519: c->local_window_max = window;
520: c->local_maxpacket = maxpack;
1.190 markus 521: c->remote_name = xstrdup(remote_name);
1.302 djm 522: c->ctl_chan = -1;
1.299 markus 523: c->delayed = 1; /* prevent call to channel_post handler */
1.426 djm 524: c->inactive_deadline = lookup_timeout(ssh, c->ctype);
1.275 djm 525: TAILQ_INIT(&c->status_confirms);
1.426 djm 526: debug("channel %d: new %s [%s] (inactive timeout: %u)",
527: found, c->ctype, remote_name, c->inactive_deadline);
1.113 markus 528: return c;
1.1 deraadt 529: }
1.52 markus 530:
1.132 markus 531: int
1.407 djm 532: channel_close_fd(struct ssh *ssh, Channel *c, int *fdp)
1.132 markus 533: {
1.407 djm 534: int ret, fd = *fdp;
1.132 markus 535:
1.407 djm 536: if (fd == -1)
537: return 0;
538:
1.427 djm 539: /* restore blocking */
540: if (*fdp == c->rfd &&
541: (c->restore_block & CHANNEL_RESTORE_RFD) != 0)
542: (void)fcntl(*fdp, F_SETFL, c->restore_flags[0]);
543: else if (*fdp == c->wfd &&
544: (c->restore_block & CHANNEL_RESTORE_WFD) != 0)
545: (void)fcntl(*fdp, F_SETFL, c->restore_flags[1]);
546: else if (*fdp == c->efd &&
547: (c->restore_block & CHANNEL_RESTORE_EFD) != 0)
548: (void)fcntl(*fdp, F_SETFL, c->restore_flags[2]);
1.407 djm 549:
1.411 djm 550: if (*fdp == c->rfd) {
551: c->io_want &= ~SSH_CHAN_IO_RFD;
552: c->io_ready &= ~SSH_CHAN_IO_RFD;
553: c->rfd = -1;
1.415 djm 554: c->pfds[0] = -1;
1.411 djm 555: }
556: if (*fdp == c->wfd) {
557: c->io_want &= ~SSH_CHAN_IO_WFD;
558: c->io_ready &= ~SSH_CHAN_IO_WFD;
559: c->wfd = -1;
1.415 djm 560: c->pfds[1] = -1;
1.411 djm 561: }
562: if (*fdp == c->efd) {
563: c->io_want &= ~SSH_CHAN_IO_EFD;
564: c->io_ready &= ~SSH_CHAN_IO_EFD;
565: c->efd = -1;
1.415 djm 566: c->pfds[2] = -1;
1.411 djm 567: }
568: if (*fdp == c->sock) {
569: c->io_want &= ~SSH_CHAN_IO_SOCK;
570: c->io_ready &= ~SSH_CHAN_IO_SOCK;
571: c->sock = -1;
1.415 djm 572: c->pfds[3] = -1;
1.411 djm 573: }
574:
1.407 djm 575: ret = close(fd);
1.411 djm 576: *fdp = -1; /* probably redundant */
1.132 markus 577: return ret;
578: }
579:
1.52 markus 580: /* Close all channel fd/socket. */
1.127 itojun 581: static void
1.367 djm 582: channel_close_fds(struct ssh *ssh, Channel *c)
583: {
1.379 tb 584: int sock = c->sock, rfd = c->rfd, wfd = c->wfd, efd = c->efd;
585:
1.407 djm 586: channel_close_fd(ssh, c, &c->sock);
1.379 tb 587: if (rfd != sock)
1.407 djm 588: channel_close_fd(ssh, c, &c->rfd);
1.379 tb 589: if (wfd != sock && wfd != rfd)
1.407 djm 590: channel_close_fd(ssh, c, &c->wfd);
1.379 tb 591: if (efd != sock && efd != rfd && efd != wfd)
1.407 djm 592: channel_close_fd(ssh, c, &c->efd);
1.367 djm 593: }
594:
595: static void
1.381 djm 596: fwd_perm_clear(struct permission *perm)
1.52 markus 597: {
1.381 djm 598: free(perm->host_to_connect);
599: free(perm->listen_host);
600: free(perm->listen_path);
1.398 dtucker 601: memset(perm, 0, sizeof(*perm));
1.367 djm 602: }
603:
1.381 djm 604: /* Returns an printable name for the specified forwarding permission list */
605: static const char *
606: fwd_ident(int who, int where)
607: {
608: if (who == FORWARD_ADM) {
609: if (where == FORWARD_LOCAL)
610: return "admin local";
611: else if (where == FORWARD_REMOTE)
612: return "admin remote";
613: } else if (who == FORWARD_USER) {
614: if (where == FORWARD_LOCAL)
615: return "user local";
616: else if (where == FORWARD_REMOTE)
617: return "user remote";
618: }
619: fatal("Unknown forward permission list %d/%d", who, where);
620: }
621:
622: /* Returns the forwarding permission list for the specified direction */
623: static struct permission_set *
624: permission_set_get(struct ssh *ssh, int where)
625: {
626: struct ssh_channels *sc = ssh->chanctxt;
1.367 djm 627:
1.381 djm 628: switch (where) {
629: case FORWARD_LOCAL:
630: return &sc->local_perms;
631: break;
632: case FORWARD_REMOTE:
633: return &sc->remote_perms;
634: break;
635: default:
1.403 djm 636: fatal_f("invalid forwarding direction %d", where);
1.381 djm 637: }
638: }
639:
1.392 dtucker 640: /* Returns pointers to the specified forwarding list and its element count */
1.381 djm 641: static void
642: permission_set_get_array(struct ssh *ssh, int who, int where,
643: struct permission ***permpp, u_int **npermpp)
644: {
645: struct permission_set *pset = permission_set_get(ssh, where);
646:
647: switch (who) {
648: case FORWARD_USER:
649: *permpp = &pset->permitted_user;
650: *npermpp = &pset->num_permitted_user;
651: break;
652: case FORWARD_ADM:
653: *permpp = &pset->permitted_admin;
654: *npermpp = &pset->num_permitted_admin;
655: break;
656: default:
1.403 djm 657: fatal_f("invalid forwarding client %d", who);
1.381 djm 658: }
659: }
660:
1.409 jsg 661: /* Adds an entry to the specified forwarding list */
1.367 djm 662: static int
1.381 djm 663: permission_set_add(struct ssh *ssh, int who, int where,
1.367 djm 664: const char *host_to_connect, int port_to_connect,
665: const char *listen_host, const char *listen_path, int listen_port,
666: Channel *downstream)
667: {
1.381 djm 668: struct permission **permp;
669: u_int n, *npermp;
1.367 djm 670:
1.381 djm 671: permission_set_get_array(ssh, who, where, &permp, &npermp);
1.367 djm 672:
1.381 djm 673: if (*npermp >= INT_MAX)
1.403 djm 674: fatal_f("%s overflow", fwd_ident(who, where));
1.367 djm 675:
1.381 djm 676: *permp = xrecallocarray(*permp, *npermp, *npermp + 1, sizeof(**permp));
677: n = (*npermp)++;
1.367 djm 678: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
1.381 djm 679: (*permp)[n].host_to_connect = MAYBE_DUP(host_to_connect);
680: (*permp)[n].port_to_connect = port_to_connect;
681: (*permp)[n].listen_host = MAYBE_DUP(listen_host);
682: (*permp)[n].listen_path = MAYBE_DUP(listen_path);
683: (*permp)[n].listen_port = listen_port;
684: (*permp)[n].downstream = downstream;
1.367 djm 685: #undef MAYBE_DUP
686: return (int)n;
687: }
688:
689: static void
690: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
691: {
692: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 693: struct permission_set *pset = &sc->local_perms;
694: struct permission *perm;
1.367 djm 695: int r;
696: u_int i;
697:
1.381 djm 698: for (i = 0; i < pset->num_permitted_user; i++) {
699: perm = &pset->permitted_user[i];
700: if (perm->downstream != c)
1.367 djm 701: continue;
702:
703: /* cancel on the server, since mux client is gone */
704: debug("channel %d: cleanup remote forward for %s:%u",
1.381 djm 705: c->self, perm->listen_host, perm->listen_port);
1.367 djm 706: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
707: (r = sshpkt_put_cstring(ssh,
708: "cancel-tcpip-forward")) != 0 ||
709: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
710: (r = sshpkt_put_cstring(ssh,
1.381 djm 711: channel_rfwd_bind_host(perm->listen_host))) != 0 ||
712: (r = sshpkt_put_u32(ssh, perm->listen_port)) != 0 ||
1.367 djm 713: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 714: fatal_fr(r, "channel %i", c->self);
1.367 djm 715: }
1.381 djm 716: fwd_perm_clear(perm); /* unregister */
1.367 djm 717: }
1.121 markus 718: }
719:
720: /* Free the channel and close its fd/socket. */
721: void
1.367 djm 722: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 723: {
1.367 djm 724: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 725: char *s;
1.209 avsm 726: u_int i, n;
1.354 markus 727: Channel *other;
1.275 djm 728: struct channel_confirm *cc;
1.121 markus 729:
1.367 djm 730: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
731: if ((other = sc->channels[i]) == NULL)
732: continue;
733: n++;
734: /* detach from mux client and prepare for closing */
735: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
736: other->type == SSH_CHANNEL_MUX_PROXY &&
737: other->mux_ctx == c) {
738: other->mux_ctx = NULL;
739: other->type = SSH_CHANNEL_OPEN;
740: other->istate = CHAN_INPUT_CLOSED;
741: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 742: }
743: }
1.209 avsm 744: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 745: c->remote_name ? c->remote_name : "???", n);
746:
1.408 mbuhl 747: if (c->type == SSH_CHANNEL_MUX_CLIENT) {
1.367 djm 748: mux_remove_remote_forwardings(ssh, c);
1.408 mbuhl 749: free(c->mux_ctx);
750: c->mux_ctx = NULL;
751: } else if (c->type == SSH_CHANNEL_MUX_LISTENER) {
1.401 djm 752: free(c->mux_ctx);
753: c->mux_ctx = NULL;
754: }
1.354 markus 755:
1.384 markus 756: if (log_level_get() >= SYSLOG_LEVEL_DEBUG3) {
757: s = channel_open_message(ssh);
758: debug3("channel %d: status: %s", c->self, s);
759: free(s);
760: }
1.121 markus 761:
1.367 djm 762: channel_close_fds(ssh, c);
763: sshbuf_free(c->input);
764: sshbuf_free(c->output);
765: sshbuf_free(c->extended);
766: c->input = c->output = c->extended = NULL;
1.321 djm 767: free(c->remote_name);
768: c->remote_name = NULL;
769: free(c->path);
770: c->path = NULL;
771: free(c->listening_addr);
772: c->listening_addr = NULL;
1.425 djm 773: free(c->xctype);
774: c->xctype = NULL;
1.275 djm 775: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
776: if (cc->abandon_cb != NULL)
1.367 djm 777: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 778: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 779: freezero(cc, sizeof(*cc));
1.275 djm 780: }
1.280 djm 781: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 782: c->filter_cleanup(ssh, c->self, c->filter_ctx);
783: sc->channels[c->self] = NULL;
1.396 jsg 784: freezero(c, sizeof(*c));
1.121 markus 785: }
786:
787: void
1.367 djm 788: channel_free_all(struct ssh *ssh)
1.121 markus 789: {
1.209 avsm 790: u_int i;
1.390 dtucker 791: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 792:
1.390 dtucker 793: for (i = 0; i < sc->channels_alloc; i++)
794: if (sc->channels[i] != NULL)
795: channel_free(ssh, sc->channels[i]);
796:
797: free(sc->channels);
798: sc->channels = NULL;
799: sc->channels_alloc = 0;
800:
801: free(sc->x11_saved_display);
802: sc->x11_saved_display = NULL;
803:
804: free(sc->x11_saved_proto);
805: sc->x11_saved_proto = NULL;
806:
807: free(sc->x11_saved_data);
808: sc->x11_saved_data = NULL;
809: sc->x11_saved_data_len = 0;
810:
811: free(sc->x11_fake_data);
812: sc->x11_fake_data = NULL;
813: sc->x11_fake_data_len = 0;
1.131 markus 814: }
815:
1.121 markus 816: /*
817: * Closes the sockets/fds of all channels. This is used to close extra file
818: * descriptors after a fork.
819: */
820: void
1.367 djm 821: channel_close_all(struct ssh *ssh)
1.121 markus 822: {
1.209 avsm 823: u_int i;
1.121 markus 824:
1.367 djm 825: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
826: if (ssh->chanctxt->channels[i] != NULL)
827: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 828: }
829:
830: /*
1.131 markus 831: * Stop listening to channels.
832: */
833: void
1.367 djm 834: channel_stop_listening(struct ssh *ssh)
1.131 markus 835: {
1.209 avsm 836: u_int i;
1.131 markus 837: Channel *c;
838:
1.367 djm 839: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
840: c = ssh->chanctxt->channels[i];
1.131 markus 841: if (c != NULL) {
842: switch (c->type) {
843: case SSH_CHANNEL_AUTH_SOCKET:
844: case SSH_CHANNEL_PORT_LISTENER:
845: case SSH_CHANNEL_RPORT_LISTENER:
846: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 847: case SSH_CHANNEL_UNIX_LISTENER:
848: case SSH_CHANNEL_RUNIX_LISTENER:
1.407 djm 849: channel_close_fd(ssh, c, &c->sock);
1.367 djm 850: channel_free(ssh, c);
1.131 markus 851: break;
852: }
853: }
854: }
855: }
856:
857: /*
1.121 markus 858: * Returns true if no channel has too much buffered data, and false if one or
859: * more channel is overfull.
860: */
861: int
1.367 djm 862: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 863: {
864: u_int i;
1.367 djm 865: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 866: Channel *c;
867:
1.367 djm 868: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
869: c = ssh->chanctxt->channels[i];
870: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
871: continue;
872: if (sshbuf_len(c->output) > maxsize) {
873: debug2("channel %d: big output buffer %zu > %u",
874: c->self, sshbuf_len(c->output), maxsize);
875: return 0;
1.121 markus 876: }
877: }
878: return 1;
879: }
880:
881: /* Returns true if any channel is still open. */
882: int
1.367 djm 883: channel_still_open(struct ssh *ssh)
1.121 markus 884: {
1.209 avsm 885: u_int i;
1.121 markus 886: Channel *c;
887:
1.367 djm 888: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
889: c = ssh->chanctxt->channels[i];
1.121 markus 890: if (c == NULL)
891: continue;
892: switch (c->type) {
893: case SSH_CHANNEL_X11_LISTENER:
894: case SSH_CHANNEL_PORT_LISTENER:
895: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 896: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 897: case SSH_CHANNEL_CLOSED:
898: case SSH_CHANNEL_AUTH_SOCKET:
899: case SSH_CHANNEL_DYNAMIC:
1.372 markus 900: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 901: case SSH_CHANNEL_CONNECTING:
902: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 903: case SSH_CHANNEL_ABANDONED:
1.336 millert 904: case SSH_CHANNEL_UNIX_LISTENER:
905: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 906: continue;
907: case SSH_CHANNEL_LARVAL:
908: continue;
909: case SSH_CHANNEL_OPENING:
910: case SSH_CHANNEL_OPEN:
1.372 markus 911: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 912: case SSH_CHANNEL_X11_OPEN:
1.302 djm 913: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 914: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 915: return 1;
916: default:
1.403 djm 917: fatal_f("bad channel type %d", c->type);
1.121 markus 918: /* NOTREACHED */
919: }
1.434 djm 920: }
921: return 0;
922: }
923:
924: /* Returns true if a channel with a TTY is open. */
925: int
926: channel_tty_open(struct ssh *ssh)
927: {
928: u_int i;
929: Channel *c;
930:
931: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
932: c = ssh->chanctxt->channels[i];
933: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
934: continue;
935: if (c->client_tty)
936: return 1;
1.121 markus 937: }
938: return 0;
939: }
940:
941: /* Returns the id of an open channel suitable for keepaliving */
942: int
1.367 djm 943: channel_find_open(struct ssh *ssh)
1.121 markus 944: {
1.209 avsm 945: u_int i;
1.121 markus 946: Channel *c;
947:
1.367 djm 948: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
949: c = ssh->chanctxt->channels[i];
1.368 djm 950: if (c == NULL || !c->have_remote_id)
1.121 markus 951: continue;
952: switch (c->type) {
953: case SSH_CHANNEL_CLOSED:
954: case SSH_CHANNEL_DYNAMIC:
1.372 markus 955: case SSH_CHANNEL_RDYNAMIC_OPEN:
956: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 957: case SSH_CHANNEL_X11_LISTENER:
958: case SSH_CHANNEL_PORT_LISTENER:
959: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 960: case SSH_CHANNEL_MUX_LISTENER:
961: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 962: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 963: case SSH_CHANNEL_OPENING:
964: case SSH_CHANNEL_CONNECTING:
965: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 966: case SSH_CHANNEL_ABANDONED:
1.336 millert 967: case SSH_CHANNEL_UNIX_LISTENER:
968: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 969: continue;
970: case SSH_CHANNEL_LARVAL:
971: case SSH_CHANNEL_AUTH_SOCKET:
972: case SSH_CHANNEL_OPEN:
973: case SSH_CHANNEL_X11_OPEN:
974: return i;
975: default:
1.403 djm 976: fatal_f("bad channel type %d", c->type);
1.121 markus 977: /* NOTREACHED */
978: }
979: }
980: return -1;
981: }
982:
1.385 djm 983: /* Returns the state of the channel's extended usage flag */
984: const char *
985: channel_format_extended_usage(const Channel *c)
986: {
987: if (c->efd == -1)
988: return "closed";
989:
990: switch (c->extended_usage) {
991: case CHAN_EXTENDED_WRITE:
992: return "write";
993: case CHAN_EXTENDED_READ:
994: return "read";
995: case CHAN_EXTENDED_IGNORE:
996: return "ignore";
997: default:
998: return "UNKNOWN";
999: }
1000: }
1001:
1.386 djm 1002: static char *
1003: channel_format_status(const Channel *c)
1004: {
1005: char *ret = NULL;
1006:
1.425 djm 1007: xasprintf(&ret, "t%d [%s] %s%u i%u/%zu o%u/%zu e[%s]/%zu "
1.411 djm 1008: "fd %d/%d/%d sock %d cc %d io 0x%02x/0x%02x",
1.425 djm 1009: c->type, c->xctype != NULL ? c->xctype : c->ctype,
1.386 djm 1010: c->have_remote_id ? "r" : "nr", c->remote_id,
1011: c->istate, sshbuf_len(c->input),
1012: c->ostate, sshbuf_len(c->output),
1013: channel_format_extended_usage(c), sshbuf_len(c->extended),
1.411 djm 1014: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan,
1015: c->io_want, c->io_ready);
1.386 djm 1016: return ret;
1017: }
1018:
1.121 markus 1019: /*
1020: * Returns a message describing the currently open forwarded connections,
1021: * suitable for sending to the client. The message contains crlf pairs for
1022: * newlines.
1023: */
1024: char *
1.367 djm 1025: channel_open_message(struct ssh *ssh)
1.121 markus 1026: {
1.367 djm 1027: struct sshbuf *buf;
1.121 markus 1028: Channel *c;
1.209 avsm 1029: u_int i;
1.367 djm 1030: int r;
1.386 djm 1031: char *cp, *ret;
1.121 markus 1032:
1.367 djm 1033: if ((buf = sshbuf_new()) == NULL)
1.403 djm 1034: fatal_f("sshbuf_new");
1.367 djm 1035: if ((r = sshbuf_putf(buf,
1036: "The following connections are open:\r\n")) != 0)
1.403 djm 1037: fatal_fr(r, "sshbuf_putf");
1.367 djm 1038: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
1039: c = ssh->chanctxt->channels[i];
1.121 markus 1040: if (c == NULL)
1041: continue;
1042: switch (c->type) {
1043: case SSH_CHANNEL_X11_LISTENER:
1044: case SSH_CHANNEL_PORT_LISTENER:
1045: case SSH_CHANNEL_RPORT_LISTENER:
1046: case SSH_CHANNEL_CLOSED:
1047: case SSH_CHANNEL_AUTH_SOCKET:
1048: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 1049: case SSH_CHANNEL_ABANDONED:
1.302 djm 1050: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 1051: case SSH_CHANNEL_UNIX_LISTENER:
1052: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 1053: continue;
1054: case SSH_CHANNEL_LARVAL:
1055: case SSH_CHANNEL_OPENING:
1056: case SSH_CHANNEL_CONNECTING:
1057: case SSH_CHANNEL_DYNAMIC:
1.372 markus 1058: case SSH_CHANNEL_RDYNAMIC_OPEN:
1059: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 1060: case SSH_CHANNEL_OPEN:
1061: case SSH_CHANNEL_X11_OPEN:
1.354 markus 1062: case SSH_CHANNEL_MUX_PROXY:
1063: case SSH_CHANNEL_MUX_CLIENT:
1.386 djm 1064: cp = channel_format_status(c);
1065: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
1066: c->self, c->remote_name, cp)) != 0) {
1067: free(cp);
1.403 djm 1068: fatal_fr(r, "sshbuf_putf");
1.386 djm 1069: }
1070: free(cp);
1.121 markus 1071: continue;
1072: default:
1.403 djm 1073: fatal_f("bad channel type %d", c->type);
1.121 markus 1074: /* NOTREACHED */
1075: }
1076: }
1.367 djm 1077: if ((ret = sshbuf_dup_string(buf)) == NULL)
1.403 djm 1078: fatal_f("sshbuf_dup_string");
1.367 djm 1079: sshbuf_free(buf);
1080: return ret;
1081: }
1082:
1083: static void
1084: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
1085: {
1086: int r;
1087:
1088: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
1089: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
1090: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1091: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1092: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
1.403 djm 1093: fatal_r(r, "%s: channel %i: open", where, c->self);
1.367 djm 1094: }
1.121 markus 1095: }
1096:
1097: void
1.367 djm 1098: channel_send_open(struct ssh *ssh, int id)
1.121 markus 1099: {
1.367 djm 1100: Channel *c = channel_lookup(ssh, id);
1101: int r;
1.180 deraadt 1102:
1.121 markus 1103: if (c == NULL) {
1.188 itojun 1104: logit("channel_send_open: %d: bad id", id);
1.121 markus 1105: return;
1106: }
1.184 markus 1107: debug2("channel %d: send open", id);
1.367 djm 1108: open_preamble(ssh, __func__, c, c->ctype);
1109: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1110: fatal_fr(r, "channel %i", c->self);
1.121 markus 1111: }
1112:
1113: void
1.367 djm 1114: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 1115: {
1.367 djm 1116: Channel *c = channel_lookup(ssh, id);
1117: int r;
1.180 deraadt 1118:
1.121 markus 1119: if (c == NULL) {
1.403 djm 1120: logit_f("%d: unknown channel id", id);
1.121 markus 1121: return;
1122: }
1.368 djm 1123: if (!c->have_remote_id)
1.403 djm 1124: fatal_f("channel %d: no remote id", c->self);
1.368 djm 1125:
1.204 djm 1126: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 1127: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
1128: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1129: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
1130: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
1.403 djm 1131: fatal_fr(r, "channel %i", c->self);
1.367 djm 1132: }
1.121 markus 1133: }
1.241 deraadt 1134:
1.121 markus 1135: void
1.367 djm 1136: channel_register_status_confirm(struct ssh *ssh, int id,
1137: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 1138: {
1139: struct channel_confirm *cc;
1140: Channel *c;
1141:
1.367 djm 1142: if ((c = channel_lookup(ssh, id)) == NULL)
1.403 djm 1143: fatal_f("%d: bad id", id);
1.275 djm 1144:
1.327 djm 1145: cc = xcalloc(1, sizeof(*cc));
1.275 djm 1146: cc->cb = cb;
1147: cc->abandon_cb = abandon_cb;
1148: cc->ctx = ctx;
1149: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
1150: }
1151:
1152: void
1.367 djm 1153: channel_register_open_confirm(struct ssh *ssh, int id,
1154: channel_open_fn *fn, void *ctx)
1.121 markus 1155: {
1.367 djm 1156: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1157:
1.121 markus 1158: if (c == NULL) {
1.403 djm 1159: logit_f("%d: bad id", id);
1.121 markus 1160: return;
1161: }
1.275 djm 1162: c->open_confirm = fn;
1163: c->open_confirm_ctx = ctx;
1.121 markus 1164: }
1.241 deraadt 1165:
1.121 markus 1166: void
1.367 djm 1167: channel_register_cleanup(struct ssh *ssh, int id,
1168: channel_callback_fn *fn, int do_close)
1.121 markus 1169: {
1.367 djm 1170: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1171:
1.121 markus 1172: if (c == NULL) {
1.403 djm 1173: logit_f("%d: bad id", id);
1.121 markus 1174: return;
1175: }
1.131 markus 1176: c->detach_user = fn;
1.225 djm 1177: c->detach_close = do_close;
1.121 markus 1178: }
1.241 deraadt 1179:
1.121 markus 1180: void
1.367 djm 1181: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 1182: {
1.367 djm 1183: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1184:
1.121 markus 1185: if (c == NULL) {
1.403 djm 1186: logit_f("%d: bad id", id);
1.121 markus 1187: return;
1.52 markus 1188: }
1.131 markus 1189: c->detach_user = NULL;
1.225 djm 1190: c->detach_close = 0;
1.121 markus 1191: }
1.241 deraadt 1192:
1.121 markus 1193: void
1.367 djm 1194: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1195: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1196: {
1.367 djm 1197: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1198:
1.121 markus 1199: if (c == NULL) {
1.403 djm 1200: logit_f("%d: bad id", id);
1.121 markus 1201: return;
1.52 markus 1202: }
1.231 reyk 1203: c->input_filter = ifn;
1204: c->output_filter = ofn;
1.279 djm 1205: c->filter_ctx = ctx;
1.280 djm 1206: c->filter_cleanup = cfn;
1.52 markus 1207: }
1208:
1.49 markus 1209: void
1.367 djm 1210: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1211: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1212: {
1.367 djm 1213: Channel *c = channel_lookup(ssh, id);
1214: int r;
1.180 deraadt 1215:
1.121 markus 1216: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1217: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1218: if (!c->have_remote_id)
1.403 djm 1219: fatal_f("channel %d: no remote id", c->self);
1.368 djm 1220:
1.367 djm 1221: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1222: c->type = SSH_CHANNEL_OPEN;
1.436 djm 1223: channel_set_used_time(ssh, c);
1.168 markus 1224: c->local_window = c->local_window_max = window_max;
1.367 djm 1225:
1226: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1227: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1228: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1229: (r = sshpkt_send(ssh)) != 0)
1.403 djm 1230: fatal_fr(r, "channel %i", c->self);
1.1 deraadt 1231: }
1232:
1.127 itojun 1233: static void
1.410 djm 1234: channel_pre_listener(struct ssh *ssh, Channel *c)
1.41 markus 1235: {
1.410 djm 1236: c->io_want = SSH_CHAN_IO_SOCK_R;
1.41 markus 1237: }
1238:
1.127 itojun 1239: static void
1.410 djm 1240: channel_pre_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1241: {
1242: debug3("channel %d: waiting for connection", c->self);
1.410 djm 1243: c->io_want = SSH_CHAN_IO_SOCK_W;
1.75 markus 1244: }
1245:
1.127 itojun 1246: static void
1.410 djm 1247: channel_pre_open(struct ssh *ssh, Channel *c)
1.41 markus 1248: {
1.410 djm 1249: c->io_want = 0;
1.44 markus 1250: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1251: c->remote_window > 0 &&
1.367 djm 1252: sshbuf_len(c->input) < c->remote_window &&
1253: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1254: c->io_want |= SSH_CHAN_IO_RFD;
1.44 markus 1255: if (c->ostate == CHAN_OUTPUT_OPEN ||
1256: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1257: if (sshbuf_len(c->output) > 0) {
1.410 djm 1258: c->io_want |= SSH_CHAN_IO_WFD;
1.44 markus 1259: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1260: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1261: debug2("channel %d: "
1262: "obuf_empty delayed efd %d/(%zu)", c->self,
1263: c->efd, sshbuf_len(c->extended));
1.172 markus 1264: else
1.367 djm 1265: chan_obuf_empty(ssh, c);
1.44 markus 1266: }
1267: }
1268: /** XXX check close conditions, too */
1.358 djm 1269: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1270: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1271: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1272: sshbuf_len(c->extended) > 0)
1.410 djm 1273: c->io_want |= SSH_CHAN_IO_EFD_W;
1.306 djm 1274: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1275: (c->extended_usage == CHAN_EXTENDED_READ ||
1276: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1277: sshbuf_len(c->extended) < c->remote_window)
1.410 djm 1278: c->io_want |= SSH_CHAN_IO_EFD_R;
1.44 markus 1279: }
1.204 djm 1280: /* XXX: What about efd? races? */
1.44 markus 1281: }
1282:
1.41 markus 1283: /*
1284: * This is a special state for X11 authentication spoofing. An opened X11
1285: * connection (when authentication spoofing is being done) remains in this
1286: * state until the first packet has been completely read. The authentication
1287: * data in that packet is then substituted by the real data if it matches the
1288: * fake data, and the channel is put into normal mode.
1.51 markus 1289: * XXX All this happens at the client side.
1.121 markus 1290: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1291: */
1.127 itojun 1292: static int
1.367 djm 1293: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1294: {
1.367 djm 1295: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1296: u_char *ucp;
1297: u_int proto_len, data_len;
1.25 markus 1298:
1.347 djm 1299: /* Is this being called after the refusal deadline? */
1.367 djm 1300: if (sc->x11_refuse_time != 0 &&
1.428 dtucker 1301: monotime() >= sc->x11_refuse_time) {
1.347 djm 1302: verbose("Rejected X11 connection after ForwardX11Timeout "
1303: "expired");
1304: return -1;
1305: }
1306:
1.41 markus 1307: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1308: if (sshbuf_len(b) < 12)
1.41 markus 1309: return 0;
1310:
1311: /* Parse the lengths of variable-length fields. */
1.367 djm 1312: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1313: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1314: proto_len = 256 * ucp[6] + ucp[7];
1315: data_len = 256 * ucp[8] + ucp[9];
1316: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1317: proto_len = ucp[6] + 256 * ucp[7];
1318: data_len = ucp[8] + 256 * ucp[9];
1319: } else {
1.194 markus 1320: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1321: ucp[0]);
1.41 markus 1322: return -1;
1323: }
1324:
1325: /* Check if the whole packet is in buffer. */
1.367 djm 1326: if (sshbuf_len(b) <
1.41 markus 1327: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1328: return 0;
1329:
1330: /* Check if authentication protocol matches. */
1.367 djm 1331: if (proto_len != strlen(sc->x11_saved_proto) ||
1332: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1333: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1334: return -1;
1335: }
1336: /* Check if authentication data matches our fake data. */
1.367 djm 1337: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1338: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1339: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1340: debug2("X11 auth data does not match fake data.");
1.41 markus 1341: return -1;
1342: }
1343: /* Check fake data length */
1.367 djm 1344: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1345: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1346: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1347: return -1;
1348: }
1349: /*
1350: * Received authentication protocol and data match
1351: * our fake data. Substitute the fake data with real
1352: * data.
1353: */
1354: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1355: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1356: return 1;
1357: }
1358:
1.423 djm 1359: void
1360: channel_force_close(struct ssh *ssh, Channel *c, int abandon)
1361: {
1362: debug3_f("channel %d: forcibly closing", c->self);
1363: if (c->istate == CHAN_INPUT_OPEN)
1364: chan_read_failed(ssh, c);
1365: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1366: sshbuf_reset(c->input);
1367: chan_ibuf_empty(ssh, c);
1368: }
1369: if (c->ostate == CHAN_OUTPUT_OPEN ||
1370: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1371: sshbuf_reset(c->output);
1372: chan_write_failed(ssh, c);
1373: }
1374: if (c->detach_user)
1375: c->detach_user(ssh, c->self, 1, NULL);
1376: if (c->efd != -1)
1377: channel_close_fd(ssh, c, &c->efd);
1378: if (abandon)
1379: c->type = SSH_CHANNEL_ABANDONED;
1.426 djm 1380: /* exempt from inactivity timeouts */
1381: c->inactive_deadline = 0;
1382: c->lastused = 0;
1.423 djm 1383: }
1384:
1.127 itojun 1385: static void
1.410 djm 1386: channel_pre_x11_open(struct ssh *ssh, Channel *c)
1.41 markus 1387: {
1.367 djm 1388: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1389:
1390: /* c->force_drain = 1; */
1391:
1.41 markus 1392: if (ret == 1) {
1393: c->type = SSH_CHANNEL_OPEN;
1.436 djm 1394: channel_set_used_time(ssh, c);
1.410 djm 1395: channel_pre_open(ssh, c);
1.41 markus 1396: } else if (ret == -1) {
1.423 djm 1397: logit("X11 connection rejected because of wrong "
1398: "authentication.");
1.367 djm 1399: debug2("X11 rejected %d i%d/o%d",
1400: c->self, c->istate, c->ostate);
1.423 djm 1401: channel_force_close(ssh, c, 0);
1.41 markus 1402: }
1403: }
1.25 markus 1404:
1.302 djm 1405: static void
1.410 djm 1406: channel_pre_mux_client(struct ssh *ssh, Channel *c)
1.302 djm 1407: {
1.410 djm 1408: c->io_want = 0;
1.304 djm 1409: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1410: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1411: c->io_want |= SSH_CHAN_IO_RFD;
1.302 djm 1412: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1413: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1414: sshbuf_reset(c->input);
1415: chan_ibuf_empty(ssh, c);
1.302 djm 1416: /* Start output drain. XXX just kill chan? */
1.367 djm 1417: chan_rcvd_oclose(ssh, c);
1.302 djm 1418: }
1419: if (c->ostate == CHAN_OUTPUT_OPEN ||
1420: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1421: if (sshbuf_len(c->output) > 0)
1.410 djm 1422: c->io_want |= SSH_CHAN_IO_WFD;
1.302 djm 1423: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1424: chan_obuf_empty(ssh, c);
1.302 djm 1425: }
1426: }
1427:
1.104 markus 1428: /* try to decode a socks4 header */
1.127 itojun 1429: static int
1.372 markus 1430: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1431: {
1.367 djm 1432: const u_char *p;
1433: char *host;
1.292 djm 1434: u_int len, have, i, found, need;
1.148 deraadt 1435: char username[256];
1.103 markus 1436: struct {
1437: u_int8_t version;
1438: u_int8_t command;
1439: u_int16_t dest_port;
1.104 markus 1440: struct in_addr dest_addr;
1.103 markus 1441: } s4_req, s4_rsp;
1.367 djm 1442: int r;
1.103 markus 1443:
1.104 markus 1444: debug2("channel %d: decode socks4", c->self);
1.109 markus 1445:
1.372 markus 1446: have = sshbuf_len(input);
1.109 markus 1447: len = sizeof(s4_req);
1448: if (have < len)
1449: return 0;
1.372 markus 1450: p = sshbuf_ptr(input);
1.292 djm 1451:
1452: need = 1;
1453: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1454: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1455: debug2("channel %d: socks4a request", c->self);
1456: /* ... and needs an extra string (the hostname) */
1457: need = 2;
1458: }
1459: /* Check for terminating NUL on the string(s) */
1.109 markus 1460: for (found = 0, i = len; i < have; i++) {
1461: if (p[i] == '\0') {
1.292 djm 1462: found++;
1463: if (found == need)
1464: break;
1.109 markus 1465: }
1466: if (i > 1024) {
1467: /* the peer is probably sending garbage */
1468: debug("channel %d: decode socks4: too long",
1469: c->self);
1470: return -1;
1471: }
1472: }
1.292 djm 1473: if (found < need)
1.109 markus 1474: return 0;
1.372 markus 1475: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1476: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1477: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1478: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.403 djm 1479: debug_r(r, "channels %d: decode socks4", c->self);
1.367 djm 1480: return -1;
1481: }
1.372 markus 1482: have = sshbuf_len(input);
1483: p = sshbuf_ptr(input);
1.364 djm 1484: if (memchr(p, '\0', have) == NULL) {
1.403 djm 1485: error("channel %d: decode socks4: unterminated user", c->self);
1.364 djm 1486: return -1;
1487: }
1.103 markus 1488: len = strlen(p);
1.106 markus 1489: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1490: len++; /* trailing '\0' */
1.103 markus 1491: strlcpy(username, p, sizeof(username));
1.403 djm 1492: if ((r = sshbuf_consume(input, len)) != 0)
1493: fatal_fr(r, "channel %d: consume", c->self);
1.321 djm 1494: free(c->path);
1495: c->path = NULL;
1.292 djm 1496: if (need == 1) { /* SOCKS4: one string */
1497: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1498: c->path = xstrdup(host);
1.292 djm 1499: } else { /* SOCKS4A: two strings */
1.372 markus 1500: have = sshbuf_len(input);
1501: p = sshbuf_ptr(input);
1.364 djm 1502: if (memchr(p, '\0', have) == NULL) {
1503: error("channel %d: decode socks4a: host not nul "
1504: "terminated", c->self);
1505: return -1;
1506: }
1.292 djm 1507: len = strlen(p);
1508: debug2("channel %d: decode socks4a: host %s/%d",
1509: c->self, p, len);
1510: len++; /* trailing '\0' */
1.293 djm 1511: if (len > NI_MAXHOST) {
1.292 djm 1512: error("channel %d: hostname \"%.100s\" too long",
1513: c->self, p);
1514: return -1;
1515: }
1.293 djm 1516: c->path = xstrdup(p);
1.403 djm 1517: if ((r = sshbuf_consume(input, len)) != 0)
1518: fatal_fr(r, "channel %d: consume", c->self);
1.292 djm 1519: }
1.103 markus 1520: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1521:
1.194 markus 1522: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1523: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1524:
1.104 markus 1525: if (s4_req.command != 1) {
1.292 djm 1526: debug("channel %d: cannot handle: %s cn %d",
1527: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1528: return -1;
1.103 markus 1529: }
1.104 markus 1530: s4_rsp.version = 0; /* vn: 0 for reply */
1531: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1532: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1533: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.403 djm 1534: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0)
1535: fatal_fr(r, "channel %d: append reply", c->self);
1.104 markus 1536: return 1;
1537: }
1538:
1.193 markus 1539: /* try to decode a socks5 header */
1540: #define SSH_SOCKS5_AUTHDONE 0x1000
1541: #define SSH_SOCKS5_NOAUTH 0x00
1542: #define SSH_SOCKS5_IPV4 0x01
1543: #define SSH_SOCKS5_DOMAIN 0x03
1544: #define SSH_SOCKS5_IPV6 0x04
1545: #define SSH_SOCKS5_CONNECT 0x01
1546: #define SSH_SOCKS5_SUCCESS 0x00
1547:
1548: static int
1.372 markus 1549: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1550: {
1.367 djm 1551: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1552: struct {
1553: u_int8_t version;
1554: u_int8_t command;
1555: u_int8_t reserved;
1556: u_int8_t atyp;
1557: } s5_req, s5_rsp;
1558: u_int16_t dest_port;
1.324 djm 1559: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1560: const u_char *p;
1.252 djm 1561: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1562: int r;
1.193 markus 1563:
1564: debug2("channel %d: decode socks5", c->self);
1.372 markus 1565: p = sshbuf_ptr(input);
1.193 markus 1566: if (p[0] != 0x05)
1567: return -1;
1.372 markus 1568: have = sshbuf_len(input);
1.193 markus 1569: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1570: /* format: ver | nmethods | methods */
1.198 djm 1571: if (have < 2)
1.193 markus 1572: return 0;
1573: nmethods = p[1];
1574: if (have < nmethods + 2)
1575: return 0;
1576: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1577: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1578: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1579: found = 1;
1580: break;
1581: }
1582: }
1583: if (!found) {
1584: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1585: c->self);
1586: return -1;
1587: }
1.403 djm 1588: if ((r = sshbuf_consume(input, nmethods + 2)) != 0)
1589: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1590: /* version, method */
1.372 markus 1591: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1.403 djm 1592: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0)
1593: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1594: c->flags |= SSH_SOCKS5_AUTHDONE;
1595: debug2("channel %d: socks5 auth done", c->self);
1596: return 0; /* need more */
1597: }
1598: debug2("channel %d: socks5 post auth", c->self);
1599: if (have < sizeof(s5_req)+1)
1600: return 0; /* need more */
1.247 deraadt 1601: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1602: if (s5_req.version != 0x05 ||
1603: s5_req.command != SSH_SOCKS5_CONNECT ||
1604: s5_req.reserved != 0x00) {
1.194 markus 1605: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1606: return -1;
1607: }
1.213 deraadt 1608: switch (s5_req.atyp){
1.193 markus 1609: case SSH_SOCKS5_IPV4:
1610: addrlen = 4;
1611: af = AF_INET;
1612: break;
1613: case SSH_SOCKS5_DOMAIN:
1614: addrlen = p[sizeof(s5_req)];
1615: af = -1;
1616: break;
1617: case SSH_SOCKS5_IPV6:
1618: addrlen = 16;
1619: af = AF_INET6;
1620: break;
1621: default:
1.194 markus 1622: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1623: return -1;
1624: }
1.252 djm 1625: need = sizeof(s5_req) + addrlen + 2;
1626: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1627: need++;
1628: if (have < need)
1.193 markus 1629: return 0;
1.403 djm 1630: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0)
1631: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1632: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1633: /* host string length */
1.403 djm 1634: if ((r = sshbuf_consume(input, 1)) != 0)
1635: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1636: }
1.372 markus 1637: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1638: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.403 djm 1639: debug_r(r, "channel %d: parse addr/port", c->self);
1.367 djm 1640: return -1;
1641: }
1.193 markus 1642: dest_addr[addrlen] = '\0';
1.321 djm 1643: free(c->path);
1644: c->path = NULL;
1.293 djm 1645: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1646: if (addrlen >= NI_MAXHOST) {
1.293 djm 1647: error("channel %d: dynamic request: socks5 hostname "
1648: "\"%.100s\" too long", c->self, dest_addr);
1649: return -1;
1650: }
1651: c->path = xstrdup(dest_addr);
1652: } else {
1653: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1654: return -1;
1655: c->path = xstrdup(ntop);
1656: }
1.193 markus 1657: c->host_port = ntohs(dest_port);
1.198 djm 1658:
1.194 markus 1659: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1660: c->self, c->path, c->host_port, s5_req.command);
1661:
1662: s5_rsp.version = 0x05;
1663: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1664: s5_rsp.reserved = 0; /* ignored */
1665: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1666: dest_port = 0; /* ignored */
1667:
1.372 markus 1668: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1669: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1670: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.403 djm 1671: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1672: return 1;
1.301 dtucker 1673: }
1674:
1675: Channel *
1.367 djm 1676: channel_connect_stdio_fwd(struct ssh *ssh,
1.432 dlg 1677: const char *host_to_connect, int port_to_connect,
1.407 djm 1678: int in, int out, int nonblock)
1.301 dtucker 1679: {
1680: Channel *c;
1681:
1.403 djm 1682: debug_f("%s:%d", host_to_connect, port_to_connect);
1.301 dtucker 1683:
1.367 djm 1684: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1685: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.407 djm 1686: 0, "stdio-forward", nonblock);
1.301 dtucker 1687:
1688: c->path = xstrdup(host_to_connect);
1689: c->host_port = port_to_connect;
1690: c->listening_port = 0;
1691: c->force_drain = 1;
1692:
1.367 djm 1693: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1.432 dlg 1694: port_open_helper(ssh, c, port_to_connect == PORT_STREAMLOCAL ?
1695: "direct-streamlocal@openssh.com" : "direct-tcpip");
1.301 dtucker 1696:
1697: return c;
1.193 markus 1698: }
1699:
1.104 markus 1700: /* dynamic port forwarding */
1.127 itojun 1701: static void
1.410 djm 1702: channel_pre_dynamic(struct ssh *ssh, Channel *c)
1.104 markus 1703: {
1.367 djm 1704: const u_char *p;
1.217 djm 1705: u_int have;
1706: int ret;
1.103 markus 1707:
1.410 djm 1708: c->io_want = 0;
1.367 djm 1709: have = sshbuf_len(c->input);
1.104 markus 1710: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1711: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1712: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1713: if (have < 3) {
1.104 markus 1714: /* need more */
1.410 djm 1715: c->io_want |= SSH_CHAN_IO_RFD;
1.104 markus 1716: return;
1717: }
1718: /* try to guess the protocol */
1.367 djm 1719: p = sshbuf_ptr(c->input);
1720: /* XXX sshbuf_peek_u8? */
1.104 markus 1721: switch (p[0]) {
1722: case 0x04:
1.372 markus 1723: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1724: break;
1725: case 0x05:
1.372 markus 1726: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1727: break;
1728: default:
1729: ret = -1;
1730: break;
1731: }
1732: if (ret < 0) {
1.367 djm 1733: chan_mark_dead(ssh, c);
1.104 markus 1734: } else if (ret == 0) {
1735: debug2("channel %d: pre_dynamic: need more", c->self);
1736: /* need more */
1.410 djm 1737: c->io_want |= SSH_CHAN_IO_RFD;
1.372 markus 1738: if (sshbuf_len(c->output))
1.410 djm 1739: c->io_want |= SSH_CHAN_IO_WFD;
1.104 markus 1740: } else {
1741: /* switch to the next state */
1742: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1743: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1744: }
1.103 markus 1745: }
1746:
1.372 markus 1747: /* simulate read-error */
1748: static void
1749: rdynamic_close(struct ssh *ssh, Channel *c)
1750: {
1751: c->type = SSH_CHANNEL_OPEN;
1.423 djm 1752: channel_force_close(ssh, c, 0);
1.372 markus 1753: }
1754:
1755: /* reverse dynamic port forwarding */
1756: static void
1.411 djm 1757: channel_before_prepare_io_rdynamic(struct ssh *ssh, Channel *c)
1.372 markus 1758: {
1759: const u_char *p;
1760: u_int have, len;
1761: int r, ret;
1762:
1763: have = sshbuf_len(c->output);
1764: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1765: /* sshbuf_dump(c->output, stderr); */
1766: /* EOF received */
1767: if (c->flags & CHAN_EOF_RCVD) {
1.403 djm 1768: if ((r = sshbuf_consume(c->output, have)) != 0)
1769: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1770: rdynamic_close(ssh, c);
1771: return;
1772: }
1773: /* check if the fixed size part of the packet is in buffer. */
1774: if (have < 3)
1775: return;
1776: /* try to guess the protocol */
1777: p = sshbuf_ptr(c->output);
1778: switch (p[0]) {
1779: case 0x04:
1780: /* switch input/output for reverse forwarding */
1781: ret = channel_decode_socks4(c, c->output, c->input);
1782: break;
1783: case 0x05:
1784: ret = channel_decode_socks5(c, c->output, c->input);
1785: break;
1786: default:
1787: ret = -1;
1788: break;
1789: }
1790: if (ret < 0) {
1791: rdynamic_close(ssh, c);
1792: } else if (ret == 0) {
1793: debug2("channel %d: pre_rdynamic: need more", c->self);
1794: /* send socks request to peer */
1795: len = sshbuf_len(c->input);
1796: if (len > 0 && len < c->remote_window) {
1797: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1798: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1799: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1800: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 1801: fatal_fr(r, "channel %i: rdynamic", c->self);
1.372 markus 1802: }
1.403 djm 1803: if ((r = sshbuf_consume(c->input, len)) != 0)
1804: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1805: c->remote_window -= len;
1806: }
1807: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1808: /* the connect failed */
1809: rdynamic_close(ssh, c);
1810: }
1811: }
1812:
1.41 markus 1813: /* This is our fake X11 server socket. */
1.127 itojun 1814: static void
1.410 djm 1815: channel_post_x11_listener(struct ssh *ssh, Channel *c)
1.41 markus 1816: {
1.113 markus 1817: Channel *nc;
1.285 djm 1818: struct sockaddr_storage addr;
1.367 djm 1819: int r, newsock, oerrno, remote_port;
1.41 markus 1820: socklen_t addrlen;
1.85 markus 1821: char buf[16384], *remote_ipaddr;
1.25 markus 1822:
1.410 djm 1823: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1824: return;
1825:
1826: debug("X11 connection requested.");
1827: addrlen = sizeof(addr);
1828: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1829: if (c->single_connection) {
1830: oerrno = errno;
1831: debug2("single_connection: closing X11 listener.");
1.407 djm 1832: channel_close_fd(ssh, c, &c->sock);
1.367 djm 1833: chan_mark_dead(ssh, c);
1834: errno = oerrno;
1835: }
1.393 deraadt 1836: if (newsock == -1) {
1.367 djm 1837: if (errno != EINTR && errno != EWOULDBLOCK &&
1838: errno != ECONNABORTED)
1839: error("accept: %.100s", strerror(errno));
1840: if (errno == EMFILE || errno == ENFILE)
1841: c->notbefore = monotime() + 1;
1842: return;
1843: }
1844: set_nodelay(newsock);
1845: remote_ipaddr = get_peer_ipaddr(newsock);
1846: remote_port = get_peer_port(newsock);
1847: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1848: remote_ipaddr, remote_port);
1849:
1.424 djm 1850: nc = channel_new(ssh, "x11-connection",
1.367 djm 1851: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1852: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1853: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1854: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1855: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.403 djm 1856: fatal_fr(r, "channel %i: reply", c->self);
1.41 markus 1857: }
1.367 djm 1858: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1859: fatal_fr(r, "channel %i: send", c->self);
1.367 djm 1860: free(remote_ipaddr);
1.41 markus 1861: }
1.25 markus 1862:
1.127 itojun 1863: static void
1.367 djm 1864: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1865: {
1.328 djm 1866: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1867: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1868: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1869: int remote_port = get_peer_port(c->sock);
1.367 djm 1870: int r;
1.303 djm 1871:
1872: if (remote_port == -1) {
1873: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1874: free(remote_ipaddr);
1.303 djm 1875: remote_ipaddr = xstrdup("127.0.0.1");
1876: remote_port = 65535;
1877: }
1.103 markus 1878:
1.367 djm 1879: free(c->remote_name);
1880: xasprintf(&c->remote_name,
1.103 markus 1881: "%s: listening port %d for %.100s port %d, "
1.328 djm 1882: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1883: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1884: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1885:
1.367 djm 1886: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1887: if (strcmp(rtype, "direct-tcpip") == 0) {
1888: /* target host, port */
1.367 djm 1889: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1890: (r = sshpkt_put_u32(ssh, c->host_port)) != 0)
1891: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1892: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1893: /* target path */
1.403 djm 1894: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1895: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1896: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1897: /* listen path */
1.403 djm 1898: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1899: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1900: } else {
1.358 djm 1901: /* listen address, port */
1.367 djm 1902: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1903: (r = sshpkt_put_u32(ssh, local_port)) != 0)
1904: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1905: }
1906: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1907: /* reserved for future owner/mode info */
1.403 djm 1908: if ((r = sshpkt_put_cstring(ssh, "")) != 0)
1909: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1910: } else {
1911: /* originator host and port */
1.367 djm 1912: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1.403 djm 1913: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0)
1914: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1915: }
1.367 djm 1916: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1917: fatal_fr(r, "channel %i: send", c->self);
1.321 djm 1918: free(remote_ipaddr);
1.328 djm 1919: free(local_ipaddr);
1.103 markus 1920: }
1921:
1.347 djm 1922: void
1.428 dtucker 1923: channel_set_x11_refuse_time(struct ssh *ssh, time_t refuse_time)
1.347 djm 1924: {
1.367 djm 1925: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1926: }
1927:
1.41 markus 1928: /*
1929: * This socket is listening for connections to a forwarded TCP/IP port.
1930: */
1.127 itojun 1931: static void
1.410 djm 1932: channel_post_port_listener(struct ssh *ssh, Channel *c)
1.41 markus 1933: {
1.103 markus 1934: Channel *nc;
1.285 djm 1935: struct sockaddr_storage addr;
1.113 markus 1936: int newsock, nextstate;
1.41 markus 1937: socklen_t addrlen;
1.103 markus 1938: char *rtype;
1.73 markus 1939:
1.410 djm 1940: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1941: return;
1942:
1943: debug("Connection to port %d forwarding to %.100s port %d requested.",
1944: c->listening_port, c->path, c->host_port);
1.103 markus 1945:
1.367 djm 1946: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1947: nextstate = SSH_CHANNEL_OPENING;
1948: rtype = "forwarded-tcpip";
1949: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1950: nextstate = SSH_CHANNEL_OPENING;
1951: rtype = "forwarded-streamlocal@openssh.com";
1952: } else if (c->host_port == PORT_STREAMLOCAL) {
1953: nextstate = SSH_CHANNEL_OPENING;
1954: rtype = "direct-streamlocal@openssh.com";
1955: } else if (c->host_port == 0) {
1956: nextstate = SSH_CHANNEL_DYNAMIC;
1957: rtype = "dynamic-tcpip";
1958: } else {
1959: nextstate = SSH_CHANNEL_OPENING;
1960: rtype = "direct-tcpip";
1961: }
1.103 markus 1962:
1.367 djm 1963: addrlen = sizeof(addr);
1964: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1965: if (newsock == -1) {
1.367 djm 1966: if (errno != EINTR && errno != EWOULDBLOCK &&
1967: errno != ECONNABORTED)
1968: error("accept: %.100s", strerror(errno));
1969: if (errno == EMFILE || errno == ENFILE)
1970: c->notbefore = monotime() + 1;
1971: return;
1.41 markus 1972: }
1.367 djm 1973: if (c->host_port != PORT_STREAMLOCAL)
1974: set_nodelay(newsock);
1975: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1976: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1977: nc->listening_port = c->listening_port;
1978: nc->host_port = c->host_port;
1979: if (c->path != NULL)
1980: nc->path = xstrdup(c->path);
1981:
1982: if (nextstate != SSH_CHANNEL_DYNAMIC)
1983: port_open_helper(ssh, nc, rtype);
1.41 markus 1984: }
1.25 markus 1985:
1.41 markus 1986: /*
1987: * This is the authentication agent socket listening for connections from
1988: * clients.
1989: */
1.127 itojun 1990: static void
1.410 djm 1991: channel_post_auth_listener(struct ssh *ssh, Channel *c)
1.41 markus 1992: {
1.113 markus 1993: Channel *nc;
1.367 djm 1994: int r, newsock;
1.285 djm 1995: struct sockaddr_storage addr;
1.41 markus 1996: socklen_t addrlen;
1.25 markus 1997:
1.410 djm 1998: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1999: return;
2000:
2001: addrlen = sizeof(addr);
2002: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 2003: if (newsock == -1) {
1.367 djm 2004: error("accept from auth socket: %.100s", strerror(errno));
2005: if (errno == EMFILE || errno == ENFILE)
2006: c->notbefore = monotime() + 1;
2007: return;
1.41 markus 2008: }
1.424 djm 2009: nc = channel_new(ssh, "agent-connection",
1.367 djm 2010: SSH_CHANNEL_OPENING, newsock, newsock, -1,
2011: c->local_window_max, c->local_maxpacket,
2012: 0, "accepted auth socket", 1);
2013: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
2014: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 2015: fatal_fr(r, "channel %i", c->self);
1.41 markus 2016: }
1.25 markus 2017:
1.127 itojun 2018: static void
1.410 djm 2019: channel_post_connecting(struct ssh *ssh, Channel *c)
1.75 markus 2020: {
1.372 markus 2021: int err = 0, sock, isopen, r;
1.129 stevesk 2022: socklen_t sz = sizeof(err);
1.114 markus 2023:
1.410 djm 2024: if ((c->io_ready & SSH_CHAN_IO_SOCK_W) == 0)
1.367 djm 2025: return;
1.368 djm 2026: if (!c->have_remote_id)
1.403 djm 2027: fatal_f("channel %d: no remote id", c->self);
1.372 markus 2028: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
2029: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.429 djm 2030:
1.393 deraadt 2031: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 2032: err = errno;
2033: error("getsockopt SO_ERROR failed");
2034: }
1.429 djm 2035:
1.367 djm 2036: if (err == 0) {
1.429 djm 2037: /* Non-blocking connection completed */
1.367 djm 2038: debug("channel %d: connected to %s port %d",
2039: c->self, c->connect_ctx.host, c->connect_ctx.port);
2040: channel_connect_ctx_free(&c->connect_ctx);
2041: c->type = SSH_CHANNEL_OPEN;
1.436 djm 2042: channel_set_used_time(ssh, c);
1.372 markus 2043: if (isopen) {
2044: /* no message necessary */
2045: } else {
2046: if ((r = sshpkt_start(ssh,
2047: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
2048: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2049: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
2050: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 2051: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0 ||
2052: (r = sshpkt_send(ssh)) != 0)
2053: fatal_fr(r, "channel %i open confirm", c->self);
1.367 djm 2054: }
1.429 djm 2055: return;
2056: }
2057: if (err == EINTR || err == EAGAIN || err == EINPROGRESS)
2058: return;
2059:
2060: /* Non-blocking connection failed */
2061: debug("channel %d: connection failed: %s", c->self, strerror(err));
2062:
2063: /* Try next address, if any */
2064: if ((sock = connect_next(&c->connect_ctx)) == -1) {
2065: /* Exhausted all addresses for this destination */
1.367 djm 2066: error("connect_to %.100s port %d: failed.",
2067: c->connect_ctx.host, c->connect_ctx.port);
2068: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 2069: if (isopen) {
2070: rdynamic_close(ssh, c);
2071: } else {
2072: if ((r = sshpkt_start(ssh,
2073: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
2074: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 2075: (r = sshpkt_put_u32(ssh,
2076: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
2077: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1.403 djm 2078: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2079: (r = sshpkt_send(ssh)) != 0)
2080: fatal_fr(r, "channel %i: failure", c->self);
1.372 markus 2081: chan_mark_dead(ssh, c);
1.75 markus 2082: }
2083: }
1.429 djm 2084:
2085: /* New non-blocking connection in progress */
2086: close(c->sock);
2087: c->sock = c->rfd = c->wfd = sock;
1.75 markus 2088: }
2089:
1.127 itojun 2090: static int
1.410 djm 2091: channel_handle_rfd(struct ssh *ssh, Channel *c)
1.41 markus 2092: {
1.214 markus 2093: char buf[CHAN_RBUF];
1.367 djm 2094: ssize_t len;
2095: int r;
1.426 djm 2096: size_t nr = 0, have, avail, maxlen = CHANNEL_MAX_READ;
1.25 markus 2097:
1.410 djm 2098: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.412 djm 2099: return 1; /* Shouldn't happen */
2100: if ((avail = sshbuf_avail(c->input)) == 0)
2101: return 1; /* Shouldn't happen */
2102:
2103: /*
2104: * For "simple" channels (i.e. not datagram or filtered), we can
2105: * read directly to the channel buffer.
2106: */
2107: if (c->input_filter == NULL && !c->datagram) {
2108: /* Only OPEN channels have valid rwin */
2109: if (c->type == SSH_CHANNEL_OPEN) {
2110: if ((have = sshbuf_len(c->input)) >= c->remote_window)
2111: return 1; /* shouldn't happen */
2112: if (maxlen > c->remote_window - have)
2113: maxlen = c->remote_window - have;
2114: }
2115: if (maxlen > avail)
2116: maxlen = avail;
1.426 djm 2117: if ((r = sshbuf_read(c->rfd, c->input, maxlen, &nr)) != 0) {
1.413 djm 2118: if (errno == EINTR || errno == EAGAIN)
2119: return 1;
1.412 djm 2120: debug2("channel %d: read failed rfd %d maxlen %zu: %s",
2121: c->self, c->rfd, maxlen, ssh_err(r));
2122: goto rfail;
2123: }
1.426 djm 2124: if (nr != 0)
1.436 djm 2125: channel_set_used_time(ssh, c);
1.367 djm 2126: return 1;
1.412 djm 2127: }
1.367 djm 2128:
2129: len = read(c->rfd, buf, sizeof(buf));
1.393 deraadt 2130: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2131: return 1;
2132: if (len <= 0) {
1.412 djm 2133: debug2("channel %d: read<=0 rfd %d len %zd: %s",
2134: c->self, c->rfd, len,
2135: len == 0 ? "closed" : strerror(errno));
2136: rfail:
1.367 djm 2137: if (c->type != SSH_CHANNEL_OPEN) {
2138: debug2("channel %d: not open", c->self);
2139: chan_mark_dead(ssh, c);
1.41 markus 2140: return -1;
1.65 markus 2141: } else {
1.367 djm 2142: chan_read_failed(ssh, c);
1.65 markus 2143: }
1.367 djm 2144: return -1;
2145: }
1.436 djm 2146: channel_set_used_time(ssh, c);
1.367 djm 2147: if (c->input_filter != NULL) {
2148: if (c->input_filter(ssh, c, buf, len) == -1) {
2149: debug2("channel %d: filter stops", c->self);
2150: chan_read_failed(ssh, c);
2151: }
2152: } else if (c->datagram) {
2153: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1.403 djm 2154: fatal_fr(r, "channel %i: put datagram", c->self);
1.412 djm 2155: }
1.41 markus 2156: return 1;
2157: }
1.241 deraadt 2158:
1.127 itojun 2159: static int
1.410 djm 2160: channel_handle_wfd(struct ssh *ssh, Channel *c)
1.41 markus 2161: {
1.95 markus 2162: struct termios tio;
1.367 djm 2163: u_char *data = NULL, *buf; /* XXX const; need filter API change */
2164: size_t dlen, olen = 0;
2165: int r, len;
2166:
1.410 djm 2167: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
2168: return 1;
2169: if (sshbuf_len(c->output) == 0)
1.367 djm 2170: return 1;
1.25 markus 2171:
1.41 markus 2172: /* Send buffered output data to the socket. */
1.367 djm 2173: olen = sshbuf_len(c->output);
2174: if (c->output_filter != NULL) {
2175: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
2176: debug2("channel %d: filter stops", c->self);
2177: if (c->type != SSH_CHANNEL_OPEN)
2178: chan_mark_dead(ssh, c);
2179: else
2180: chan_write_failed(ssh, c);
2181: return -1;
1.231 reyk 2182: }
1.367 djm 2183: } else if (c->datagram) {
2184: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1.403 djm 2185: fatal_fr(r, "channel %i: get datagram", c->self);
1.369 djm 2186: buf = data;
1.367 djm 2187: } else {
2188: buf = data = sshbuf_mutable_ptr(c->output);
2189: dlen = sshbuf_len(c->output);
2190: }
1.231 reyk 2191:
1.367 djm 2192: if (c->datagram) {
2193: /* ignore truncated writes, datagrams might get lost */
1.374 djm 2194: len = write(c->wfd, buf, dlen);
1.367 djm 2195: free(data);
1.393 deraadt 2196: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 2197: return 1;
1.367 djm 2198: if (len <= 0)
2199: goto write_fail;
2200: goto out;
2201: }
2202:
2203: len = write(c->wfd, buf, dlen);
1.393 deraadt 2204: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2205: return 1;
2206: if (len <= 0) {
2207: write_fail:
2208: if (c->type != SSH_CHANNEL_OPEN) {
2209: debug2("channel %d: not open", c->self);
2210: chan_mark_dead(ssh, c);
1.41 markus 2211: return -1;
1.367 djm 2212: } else {
2213: chan_write_failed(ssh, c);
1.91 markus 2214: }
1.367 djm 2215: return -1;
2216: }
1.436 djm 2217: channel_set_used_time(ssh, c);
1.367 djm 2218: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2219: if (tcgetattr(c->wfd, &tio) == 0 &&
2220: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2221: /*
2222: * Simulate echo to reduce the impact of
2223: * traffic analysis. We need to match the
2224: * size of a SSH2_MSG_CHANNEL_DATA message
2225: * (4 byte channel id + buf)
2226: */
2227: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2228: (r = sshpkt_send(ssh)) != 0)
1.403 djm 2229: fatal_fr(r, "channel %i: ignore", c->self);
1.25 markus 2230: }
1.367 djm 2231: }
1.403 djm 2232: if ((r = sshbuf_consume(c->output, len)) != 0)
2233: fatal_fr(r, "channel %i: consume", c->self);
1.309 djm 2234: out:
1.367 djm 2235: c->local_consumed += olen - sshbuf_len(c->output);
2236:
2237: return 1;
2238: }
2239:
2240: static int
1.410 djm 2241: channel_handle_efd_write(struct ssh *ssh, Channel *c)
1.367 djm 2242: {
2243: int r;
2244: ssize_t len;
2245:
1.410 djm 2246: if ((c->io_ready & SSH_CHAN_IO_EFD_W) == 0)
2247: return 1;
2248: if (sshbuf_len(c->extended) == 0)
1.367 djm 2249: return 1;
2250:
2251: len = write(c->efd, sshbuf_ptr(c->extended),
2252: sshbuf_len(c->extended));
2253: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 deraadt 2254: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2255: return 1;
2256: if (len <= 0) {
2257: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1.407 djm 2258: channel_close_fd(ssh, c, &c->efd);
1.367 djm 2259: } else {
1.403 djm 2260: if ((r = sshbuf_consume(c->extended, len)) != 0)
2261: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2262: c->local_consumed += len;
1.436 djm 2263: channel_set_used_time(ssh, c);
1.367 djm 2264: }
1.44 markus 2265: return 1;
2266: }
1.241 deraadt 2267:
1.127 itojun 2268: static int
1.410 djm 2269: channel_handle_efd_read(struct ssh *ssh, Channel *c)
1.44 markus 2270: {
1.214 markus 2271: char buf[CHAN_RBUF];
1.367 djm 2272: int r;
2273: ssize_t len;
2274:
1.410 djm 2275: if ((c->io_ready & SSH_CHAN_IO_EFD_R) == 0)
1.367 djm 2276: return 1;
1.44 markus 2277:
1.367 djm 2278: len = read(c->efd, buf, sizeof(buf));
2279: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 deraadt 2280: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2281: return 1;
2282: if (len <= 0) {
1.403 djm 2283: debug2("channel %d: closing read-efd %d", c->self, c->efd);
1.407 djm 2284: channel_close_fd(ssh, c, &c->efd);
1.426 djm 2285: return 1;
2286: }
1.436 djm 2287: channel_set_used_time(ssh, c);
1.426 djm 2288: if (c->extended_usage == CHAN_EXTENDED_IGNORE)
1.403 djm 2289: debug3("channel %d: discard efd", c->self);
2290: else if ((r = sshbuf_put(c->extended, buf, len)) != 0)
2291: fatal_fr(r, "channel %i: append", c->self);
1.44 markus 2292: return 1;
2293: }
1.241 deraadt 2294:
1.127 itojun 2295: static int
1.410 djm 2296: channel_handle_efd(struct ssh *ssh, Channel *c)
1.44 markus 2297: {
1.367 djm 2298: if (c->efd == -1)
2299: return 1;
2300:
2301: /** XXX handle drain efd, too */
2302:
2303: if (c->extended_usage == CHAN_EXTENDED_WRITE)
1.410 djm 2304: return channel_handle_efd_write(ssh, c);
1.367 djm 2305: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2306: c->extended_usage == CHAN_EXTENDED_IGNORE)
1.410 djm 2307: return channel_handle_efd_read(ssh, c);
1.367 djm 2308:
2309: return 1;
2310: }
2311:
2312: static int
2313: channel_check_window(struct ssh *ssh, Channel *c)
2314: {
2315: int r;
2316:
1.104 markus 2317: if (c->type == SSH_CHANNEL_OPEN &&
2318: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2319: ((c->local_window_max - c->local_window >
1.269 markus 2320: c->local_maxpacket*3) ||
2321: c->local_window < c->local_window_max/2) &&
1.44 markus 2322: c->local_consumed > 0) {
1.368 djm 2323: if (!c->have_remote_id)
1.403 djm 2324: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2325: if ((r = sshpkt_start(ssh,
2326: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2327: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2328: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2329: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2330: fatal_fr(r, "channel %i", c->self);
1.367 djm 2331: }
1.403 djm 2332: debug2("channel %d: window %d sent adjust %d", c->self,
2333: c->local_window, c->local_consumed);
1.44 markus 2334: c->local_window += c->local_consumed;
2335: c->local_consumed = 0;
1.1 deraadt 2336: }
1.41 markus 2337: return 1;
1.1 deraadt 2338: }
2339:
1.127 itojun 2340: static void
1.410 djm 2341: channel_post_open(struct ssh *ssh, Channel *c)
1.41 markus 2342: {
1.410 djm 2343: channel_handle_rfd(ssh, c);
2344: channel_handle_wfd(ssh, c);
2345: channel_handle_efd(ssh, c);
1.367 djm 2346: channel_check_window(ssh, c);
1.44 markus 2347: }
2348:
1.302 djm 2349: static u_int
1.367 djm 2350: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2351: {
2352: char buf[CHAN_RBUF];
1.367 djm 2353: ssize_t len;
1.302 djm 2354: u_int rlen;
1.367 djm 2355: int r;
1.302 djm 2356:
1.367 djm 2357: if (sshbuf_len(c->input) < need) {
2358: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2359: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 deraadt 2360: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2361: return sshbuf_len(c->input);
1.302 djm 2362: if (len <= 0) {
1.367 djm 2363: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2364: c->self, c->rfd, len);
1.367 djm 2365: chan_read_failed(ssh, c);
1.349 naddy 2366: return 0;
1.403 djm 2367: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
2368: fatal_fr(r, "channel %i: append", c->self);
1.302 djm 2369: }
1.367 djm 2370: return sshbuf_len(c->input);
1.302 djm 2371: }
2372:
2373: static void
1.410 djm 2374: channel_post_mux_client_read(struct ssh *ssh, Channel *c)
1.302 djm 2375: {
2376: u_int need;
2377:
1.410 djm 2378: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.367 djm 2379: return;
2380: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2381: return;
2382: if (c->mux_pause)
2383: return;
2384:
2385: /*
2386: * Don't not read past the precise end of packets to
2387: * avoid disrupting fd passing.
2388: */
2389: if (read_mux(ssh, c, 4) < 4) /* read header */
2390: return;
2391: /* XXX sshbuf_peek_u32 */
2392: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2393: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2394: if (need > CHANNEL_MUX_MAX_PACKET) {
2395: debug2("channel %d: packet too big %u > %u",
2396: c->self, CHANNEL_MUX_MAX_PACKET, need);
2397: chan_rcvd_oclose(ssh, c);
2398: return;
2399: }
2400: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2401: return;
2402: if (c->mux_rcb(ssh, c) != 0) {
2403: debug("channel %d: mux_rcb failed", c->self);
2404: chan_mark_dead(ssh, c);
2405: return;
1.302 djm 2406: }
1.367 djm 2407: }
2408:
2409: static void
1.410 djm 2410: channel_post_mux_client_write(struct ssh *ssh, Channel *c)
1.367 djm 2411: {
2412: ssize_t len;
2413: int r;
1.302 djm 2414:
1.410 djm 2415: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
2416: return;
2417: if (sshbuf_len(c->output) == 0)
1.367 djm 2418: return;
2419:
2420: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 deraadt 2421: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2422: return;
2423: if (len <= 0) {
2424: chan_mark_dead(ssh, c);
2425: return;
1.302 djm 2426: }
1.367 djm 2427: if ((r = sshbuf_consume(c->output, len)) != 0)
1.403 djm 2428: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2429: }
2430:
2431: static void
1.410 djm 2432: channel_post_mux_client(struct ssh *ssh, Channel *c)
1.367 djm 2433: {
1.410 djm 2434: channel_post_mux_client_read(ssh, c);
2435: channel_post_mux_client_write(ssh, c);
1.302 djm 2436: }
2437:
2438: static void
1.410 djm 2439: channel_post_mux_listener(struct ssh *ssh, Channel *c)
1.302 djm 2440: {
2441: Channel *nc;
2442: struct sockaddr_storage addr;
2443: socklen_t addrlen;
2444: int newsock;
2445: uid_t euid;
2446: gid_t egid;
2447:
1.410 djm 2448: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.302 djm 2449: return;
2450:
2451: debug("multiplexing control connection");
2452:
2453: /*
2454: * Accept connection on control socket
2455: */
2456: memset(&addr, 0, sizeof(addr));
2457: addrlen = sizeof(addr);
2458: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2459: &addrlen)) == -1) {
1.403 djm 2460: error_f("accept: %s", strerror(errno));
1.317 djm 2461: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2462: c->notbefore = monotime() + 1;
1.302 djm 2463: return;
2464: }
2465:
1.393 deraadt 2466: if (getpeereid(newsock, &euid, &egid) == -1) {
1.403 djm 2467: error_f("getpeereid failed: %s", strerror(errno));
1.302 djm 2468: close(newsock);
2469: return;
2470: }
2471: if ((euid != 0) && (getuid() != euid)) {
2472: error("multiplex uid mismatch: peer euid %u != uid %u",
2473: (u_int)euid, (u_int)getuid());
2474: close(newsock);
2475: return;
2476: }
1.424 djm 2477: nc = channel_new(ssh, "mux-control", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2478: newsock, newsock, -1, c->local_window_max,
2479: c->local_maxpacket, 0, "mux-control", 1);
2480: nc->mux_rcb = c->mux_rcb;
1.403 djm 2481: debug3_f("new mux channel %d fd %d", nc->self, nc->sock);
1.302 djm 2482: /* establish state */
1.367 djm 2483: nc->mux_rcb(ssh, nc);
1.302 djm 2484: /* mux state transitions must not elicit protocol messages */
2485: nc->flags |= CHAN_LOCAL;
2486: }
2487:
1.127 itojun 2488: static void
1.367 djm 2489: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2490: {
1.367 djm 2491: chan_fn **pre, **post;
2492:
2493: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
1.406 djm 2494: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
1.403 djm 2495: fatal_f("allocation failed");
1.367 djm 2496:
2497: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2498: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2499: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2500: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2501: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2502: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2503: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2504: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2505: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2506: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2507: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2508: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2509: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2510:
2511: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2512: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2513: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2514: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2515: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2516: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2517: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2518: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2519: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2520: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2521: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2522: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2523:
1.367 djm 2524: sc->channel_pre = pre;
2525: sc->channel_post = post;
1.44 markus 2526: }
2527:
1.140 markus 2528: /* gc dead channels */
2529: static void
1.367 djm 2530: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2531: {
2532: if (c == NULL)
2533: return;
2534: if (c->detach_user != NULL) {
1.367 djm 2535: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2536: return;
1.385 djm 2537:
1.194 markus 2538: debug2("channel %d: gc: notify user", c->self);
1.423 djm 2539: c->detach_user(ssh, c->self, 0, NULL);
1.140 markus 2540: /* if we still have a callback */
2541: if (c->detach_user != NULL)
2542: return;
1.194 markus 2543: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2544: }
1.367 djm 2545: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2546: return;
1.194 markus 2547: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2548: channel_free(ssh, c);
1.140 markus 2549: }
2550:
1.367 djm 2551: enum channel_table { CHAN_PRE, CHAN_POST };
2552:
1.127 itojun 2553: static void
1.422 djm 2554: channel_handler(struct ssh *ssh, int table, struct timespec *timeout)
1.41 markus 2555: {
1.367 djm 2556: struct ssh_channels *sc = ssh->chanctxt;
2557: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2558: u_int i, oalloc;
1.41 markus 2559: Channel *c;
1.317 djm 2560: time_t now;
1.25 markus 2561:
1.322 dtucker 2562: now = monotime();
1.367 djm 2563: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2564: c = sc->channels[i];
1.113 markus 2565: if (c == NULL)
1.41 markus 2566: continue;
1.417 djm 2567: /* Try to keep IO going while rekeying */
2568: if (ssh_packet_is_rekeying(ssh) && c->type != SSH_CHANNEL_OPEN)
2569: continue;
1.299 markus 2570: if (c->delayed) {
1.367 djm 2571: if (table == CHAN_PRE)
1.299 markus 2572: c->delayed = 0;
2573: else
2574: continue;
2575: }
1.317 djm 2576: if (ftab[c->type] != NULL) {
1.436 djm 2577: if (table == CHAN_PRE && c->type == SSH_CHANNEL_OPEN &&
2578: channel_get_expiry(ssh, c) != 0 &&
2579: now >= channel_get_expiry(ssh, c)) {
1.426 djm 2580: /* channel closed for inactivity */
2581: verbose("channel %d: closing after %u seconds "
2582: "of inactivity", c->self,
2583: c->inactive_deadline);
2584: channel_force_close(ssh, c, 1);
2585: } else if (c->notbefore <= now) {
2586: /* Run handlers that are not paused. */
1.410 djm 2587: (*ftab[c->type])(ssh, c);
1.426 djm 2588: /* inactivity timeouts must interrupt poll() */
2589: if (timeout != NULL &&
2590: c->type == SSH_CHANNEL_OPEN &&
1.436 djm 2591: channel_get_expiry(ssh, c) != 0) {
1.426 djm 2592: ptimeout_deadline_monotime(timeout,
1.436 djm 2593: channel_get_expiry(ssh, c));
1.426 djm 2594: }
2595: } else if (timeout != NULL) {
1.317 djm 2596: /*
1.426 djm 2597: * Arrange for poll() wakeup when channel pause
1.422 djm 2598: * timer expires.
1.317 djm 2599: */
1.422 djm 2600: ptimeout_deadline_monotime(timeout,
2601: c->notbefore);
1.317 djm 2602: }
2603: }
1.367 djm 2604: channel_garbage_collect(ssh, c);
1.1 deraadt 2605: }
2606: }
2607:
1.121 markus 2608: /*
1.411 djm 2609: * Create sockets before preparing IO.
1.372 markus 2610: * This is necessary for things that need to happen after reading
1.411 djm 2611: * the network-input but need to be completed before IO event setup, e.g.
2612: * because they may create new channels.
1.372 markus 2613: */
2614: static void
1.411 djm 2615: channel_before_prepare_io(struct ssh *ssh)
1.372 markus 2616: {
2617: struct ssh_channels *sc = ssh->chanctxt;
2618: Channel *c;
2619: u_int i, oalloc;
2620:
2621: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2622: c = sc->channels[i];
2623: if (c == NULL)
2624: continue;
2625: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
1.411 djm 2626: channel_before_prepare_io_rdynamic(ssh, c);
2627: }
2628: }
2629:
2630: static void
2631: dump_channel_poll(const char *func, const char *what, Channel *c,
2632: u_int pollfd_offset, struct pollfd *pfd)
2633: {
2634: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2635: debug3("%s: channel %d: %s r%d w%d e%d s%d c->pfds [ %d %d %d %d ] "
2636: "io_want 0x%02x io_ready 0x%02x pfd[%u].fd=%d "
2637: "pfd.ev 0x%02x pfd.rev 0x%02x", func, c->self, what,
2638: c->rfd, c->wfd, c->efd, c->sock,
2639: c->pfds[0], c->pfds[1], c->pfds[2], c->pfds[3],
2640: c->io_want, c->io_ready,
2641: pollfd_offset, pfd->fd, pfd->events, pfd->revents);
1.411 djm 2642: #endif
2643: }
2644:
2645: /* Prepare pollfd entries for a single channel */
2646: static void
2647: channel_prepare_pollfd(Channel *c, u_int *next_pollfd,
2648: struct pollfd *pfd, u_int npfd)
2649: {
1.415 djm 2650: u_int ev, p = *next_pollfd;
1.411 djm 2651:
2652: if (c == NULL)
2653: return;
2654: if (p + 4 > npfd) {
2655: /* Shouldn't happen */
2656: fatal_f("channel %d: bad pfd offset %u (max %u)",
2657: c->self, p, npfd);
2658: }
1.415 djm 2659: c->pfds[0] = c->pfds[1] = c->pfds[2] = c->pfds[3] = -1;
1.411 djm 2660: /*
2661: * prepare c->rfd
2662: *
2663: * This is a special case, since c->rfd might be the same as
2664: * c->wfd, c->efd and/or c->sock. Handle those here if they want
2665: * IO too.
2666: */
2667: if (c->rfd != -1) {
1.415 djm 2668: ev = 0;
1.411 djm 2669: if ((c->io_want & SSH_CHAN_IO_RFD) != 0)
1.415 djm 2670: ev |= POLLIN;
1.411 djm 2671: /* rfd == wfd */
1.415 djm 2672: if (c->wfd == c->rfd) {
2673: if ((c->io_want & SSH_CHAN_IO_WFD) != 0)
2674: ev |= POLLOUT;
2675: }
1.411 djm 2676: /* rfd == efd */
1.415 djm 2677: if (c->efd == c->rfd) {
2678: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
2679: ev |= POLLIN;
2680: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
2681: ev |= POLLOUT;
2682: }
1.411 djm 2683: /* rfd == sock */
1.415 djm 2684: if (c->sock == c->rfd) {
2685: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
2686: ev |= POLLIN;
2687: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
2688: ev |= POLLOUT;
2689: }
2690: /* Pack a pfd entry if any event armed for this fd */
2691: if (ev != 0) {
2692: c->pfds[0] = p;
2693: pfd[p].fd = c->rfd;
2694: pfd[p].events = ev;
2695: dump_channel_poll(__func__, "rfd", c, p, &pfd[p]);
2696: p++;
2697: }
1.411 djm 2698: }
1.415 djm 2699: /* prepare c->wfd if wanting IO and not already handled above */
1.411 djm 2700: if (c->wfd != -1 && c->rfd != c->wfd) {
1.415 djm 2701: ev = 0;
2702: if ((c->io_want & SSH_CHAN_IO_WFD))
2703: ev |= POLLOUT;
2704: /* Pack a pfd entry if any event armed for this fd */
2705: if (ev != 0) {
2706: c->pfds[1] = p;
2707: pfd[p].fd = c->wfd;
2708: pfd[p].events = ev;
2709: dump_channel_poll(__func__, "wfd", c, p, &pfd[p]);
2710: p++;
2711: }
1.411 djm 2712: }
1.415 djm 2713: /* prepare c->efd if wanting IO and not already handled above */
1.411 djm 2714: if (c->efd != -1 && c->rfd != c->efd) {
1.415 djm 2715: ev = 0;
1.411 djm 2716: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
1.415 djm 2717: ev |= POLLIN;
1.411 djm 2718: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
1.415 djm 2719: ev |= POLLOUT;
2720: /* Pack a pfd entry if any event armed for this fd */
2721: if (ev != 0) {
2722: c->pfds[2] = p;
2723: pfd[p].fd = c->efd;
2724: pfd[p].events = ev;
2725: dump_channel_poll(__func__, "efd", c, p, &pfd[p]);
2726: p++;
2727: }
1.411 djm 2728: }
1.415 djm 2729: /* prepare c->sock if wanting IO and not already handled above */
1.411 djm 2730: if (c->sock != -1 && c->rfd != c->sock) {
1.415 djm 2731: ev = 0;
1.411 djm 2732: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
1.415 djm 2733: ev |= POLLIN;
1.411 djm 2734: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
1.415 djm 2735: ev |= POLLOUT;
2736: /* Pack a pfd entry if any event armed for this fd */
2737: if (ev != 0) {
2738: c->pfds[3] = p;
2739: pfd[p].fd = c->sock;
2740: pfd[p].events = 0;
2741: dump_channel_poll(__func__, "sock", c, p, &pfd[p]);
2742: p++;
2743: }
1.372 markus 2744: }
1.411 djm 2745: *next_pollfd = p;
1.372 markus 2746: }
2747:
1.411 djm 2748: /* * Allocate/prepare poll structure */
1.49 markus 2749: void
1.411 djm 2750: channel_prepare_poll(struct ssh *ssh, struct pollfd **pfdp, u_int *npfd_allocp,
1.422 djm 2751: u_int *npfd_activep, u_int npfd_reserved, struct timespec *timeout)
1.41 markus 2752: {
1.410 djm 2753: struct ssh_channels *sc = ssh->chanctxt;
1.411 djm 2754: u_int i, oalloc, p, npfd = npfd_reserved;
2755:
2756: channel_before_prepare_io(ssh); /* might create a new channel */
1.416 djm 2757: /* clear out I/O flags from last poll */
2758: for (i = 0; i < sc->channels_alloc; i++) {
2759: if (sc->channels[i] == NULL)
2760: continue;
2761: sc->channels[i]->io_want = sc->channels[i]->io_ready = 0;
2762: }
1.411 djm 2763: /* Allocate 4x pollfd for each channel (rfd, wfd, efd, sock) */
2764: if (sc->channels_alloc >= (INT_MAX / 4) - npfd_reserved)
2765: fatal_f("too many channels"); /* shouldn't happen */
1.417 djm 2766: npfd += sc->channels_alloc * 4;
1.411 djm 2767: if (npfd > *npfd_allocp) {
2768: *pfdp = xrecallocarray(*pfdp, *npfd_allocp,
2769: npfd, sizeof(**pfdp));
2770: *npfd_allocp = npfd;
2771: }
2772: *npfd_activep = npfd_reserved;
2773: oalloc = sc->channels_alloc;
1.372 markus 2774:
1.422 djm 2775: channel_handler(ssh, CHAN_PRE, timeout);
1.84 markus 2776:
1.411 djm 2777: if (oalloc != sc->channels_alloc) {
2778: /* shouldn't happen */
2779: fatal_f("channels_alloc changed during CHAN_PRE "
2780: "(was %u, now %u)", oalloc, sc->channels_alloc);
2781: }
1.84 markus 2782:
1.411 djm 2783: /* Prepare pollfd */
2784: p = npfd_reserved;
2785: for (i = 0; i < sc->channels_alloc; i++)
2786: channel_prepare_pollfd(sc->channels[i], &p, *pfdp, npfd);
2787: *npfd_activep = p;
2788: }
2789:
2790: static void
1.415 djm 2791: fd_ready(Channel *c, int p, struct pollfd *pfds, u_int npfd, int fd,
1.411 djm 2792: const char *what, u_int revents_mask, u_int ready)
2793: {
2794: struct pollfd *pfd = &pfds[p];
1.410 djm 2795:
1.411 djm 2796: if (fd == -1)
2797: return;
1.415 djm 2798: if (p == -1 || (u_int)p >= npfd)
2799: fatal_f("channel %d: bad pfd %d (max %u)", c->self, p, npfd);
1.411 djm 2800: dump_channel_poll(__func__, what, c, p, pfd);
2801: if (pfd->fd != fd) {
2802: fatal("channel %d: inconsistent %s fd=%d pollfd[%u].fd %d "
2803: "r%d w%d e%d s%d", c->self, what, fd, p, pfd->fd,
2804: c->rfd, c->wfd, c->efd, c->sock);
2805: }
2806: if ((pfd->revents & POLLNVAL) != 0) {
2807: fatal("channel %d: invalid %s pollfd[%u].fd %d r%d w%d e%d s%d",
2808: c->self, what, p, pfd->fd, c->rfd, c->wfd, c->efd, c->sock);
1.410 djm 2809: }
1.411 djm 2810: if ((pfd->revents & (revents_mask|POLLHUP|POLLERR)) != 0)
2811: c->io_ready |= ready & c->io_want;
1.41 markus 2812: }
2813:
1.121 markus 2814: /*
1.411 djm 2815: * After poll, perform any appropriate operations for channels which have
1.121 markus 2816: * events pending.
2817: */
1.49 markus 2818: void
1.411 djm 2819: channel_after_poll(struct ssh *ssh, struct pollfd *pfd, u_int npfd)
1.41 markus 2820: {
1.410 djm 2821: struct ssh_channels *sc = ssh->chanctxt;
1.415 djm 2822: u_int i;
2823: int p;
1.410 djm 2824: Channel *c;
2825:
1.411 djm 2826: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2827: for (p = 0; p < (int)npfd; p++) {
1.411 djm 2828: if (pfd[p].revents == 0)
2829: continue;
2830: debug_f("pfd[%u].fd %d rev 0x%04x",
2831: p, pfd[p].fd, pfd[p].revents);
2832: }
2833: #endif
2834:
2835: /* Convert pollfd into c->io_ready */
2836: for (i = 0; i < sc->channels_alloc; i++) {
1.410 djm 2837: c = sc->channels[i];
1.415 djm 2838: if (c == NULL)
1.410 djm 2839: continue;
1.411 djm 2840: /* if rfd is shared with efd/sock then wfd should be too */
2841: if (c->rfd != -1 && c->wfd != -1 && c->rfd != c->wfd &&
2842: (c->rfd == c->efd || c->rfd == c->sock)) {
2843: /* Shouldn't happen */
2844: fatal_f("channel %d: unexpected fds r%d w%d e%d s%d",
2845: c->self, c->rfd, c->wfd, c->efd, c->sock);
2846: }
1.410 djm 2847: c->io_ready = 0;
1.411 djm 2848: /* rfd, potentially shared with wfd, efd and sock */
1.415 djm 2849: if (c->rfd != -1 && (p = c->pfds[0]) != -1) {
2850: fd_ready(c, p, pfd, npfd, c->rfd,
2851: "rfd", POLLIN, SSH_CHAN_IO_RFD);
1.411 djm 2852: if (c->rfd == c->wfd) {
1.415 djm 2853: fd_ready(c, p, pfd, npfd, c->wfd,
2854: "wfd/r", POLLOUT, SSH_CHAN_IO_WFD);
1.411 djm 2855: }
2856: if (c->rfd == c->efd) {
1.415 djm 2857: fd_ready(c, p, pfd, npfd, c->efd,
2858: "efdr/r", POLLIN, SSH_CHAN_IO_EFD_R);
2859: fd_ready(c, p, pfd, npfd, c->efd,
2860: "efdw/r", POLLOUT, SSH_CHAN_IO_EFD_W);
1.411 djm 2861: }
2862: if (c->rfd == c->sock) {
1.415 djm 2863: fd_ready(c, p, pfd, npfd, c->sock,
2864: "sockr/r", POLLIN, SSH_CHAN_IO_SOCK_R);
2865: fd_ready(c, p, pfd, npfd, c->sock,
2866: "sockw/r", POLLOUT, SSH_CHAN_IO_SOCK_W);
1.411 djm 2867: }
1.415 djm 2868: dump_channel_poll(__func__, "rfd", c, p, pfd);
1.411 djm 2869: }
2870: /* wfd */
1.415 djm 2871: if (c->wfd != -1 && c->wfd != c->rfd &&
2872: (p = c->pfds[1]) != -1) {
2873: fd_ready(c, p, pfd, npfd, c->wfd,
2874: "wfd", POLLOUT, SSH_CHAN_IO_WFD);
2875: dump_channel_poll(__func__, "wfd", c, p, pfd);
1.411 djm 2876: }
2877: /* efd */
1.415 djm 2878: if (c->efd != -1 && c->efd != c->rfd &&
2879: (p = c->pfds[2]) != -1) {
2880: fd_ready(c, p, pfd, npfd, c->efd,
2881: "efdr", POLLIN, SSH_CHAN_IO_EFD_R);
2882: fd_ready(c, p, pfd, npfd, c->efd,
2883: "efdw", POLLOUT, SSH_CHAN_IO_EFD_W);
2884: dump_channel_poll(__func__, "efd", c, p, pfd);
1.411 djm 2885: }
2886: /* sock */
1.415 djm 2887: if (c->sock != -1 && c->sock != c->rfd &&
2888: (p = c->pfds[3]) != -1) {
2889: fd_ready(c, p, pfd, npfd, c->sock,
2890: "sockr", POLLIN, SSH_CHAN_IO_SOCK_R);
2891: fd_ready(c, p, pfd, npfd, c->sock,
2892: "sockw", POLLOUT, SSH_CHAN_IO_SOCK_W);
2893: dump_channel_poll(__func__, "sock", c, p, pfd);
1.411 djm 2894: }
1.410 djm 2895: }
2896: channel_handler(ssh, CHAN_POST, NULL);
1.367 djm 2897: }
2898:
2899: /*
2900: * Enqueue data for channels with open or draining c->input.
1.433 djm 2901: * Returns non-zero if a packet was enqueued.
1.367 djm 2902: */
1.433 djm 2903: static int
1.367 djm 2904: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2905: {
1.373 djm 2906: size_t len, plen;
2907: const u_char *pkt;
1.367 djm 2908: int r;
2909:
2910: if ((len = sshbuf_len(c->input)) == 0) {
2911: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2912: /*
2913: * input-buffer is empty and read-socket shutdown:
2914: * tell peer, that we will not send more data:
2915: * send IEOF.
2916: * hack for extended data: delay EOF if EFD still
2917: * in use.
2918: */
2919: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2920: debug2("channel %d: "
2921: "ibuf_empty delayed efd %d/(%zu)",
2922: c->self, c->efd, sshbuf_len(c->extended));
2923: else
2924: chan_ibuf_empty(ssh, c);
2925: }
1.433 djm 2926: return 0;
1.367 djm 2927: }
2928:
1.368 djm 2929: if (!c->have_remote_id)
1.403 djm 2930: fatal_f("channel %d: no remote id", c->self);
1.368 djm 2931:
1.367 djm 2932: if (c->datagram) {
2933: /* Check datagram will fit; drop if not */
1.373 djm 2934: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
1.403 djm 2935: fatal_fr(r, "channel %i: get datagram", c->self);
1.367 djm 2936: /*
2937: * XXX this does tail-drop on the datagram queue which is
2938: * usually suboptimal compared to head-drop. Better to have
2939: * backpressure at read time? (i.e. read + discard)
2940: */
1.373 djm 2941: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2942: debug("channel %d: datagram too big", c->self);
1.433 djm 2943: return 0;
1.367 djm 2944: }
2945: /* Enqueue it */
2946: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2947: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2948: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.403 djm 2949: (r = sshpkt_send(ssh)) != 0)
2950: fatal_fr(r, "channel %i: send datagram", c->self);
1.373 djm 2951: c->remote_window -= plen;
1.433 djm 2952: return 1;
1.367 djm 2953: }
2954:
2955: /* Enqueue packet for buffered data. */
2956: if (len > c->remote_window)
2957: len = c->remote_window;
2958: if (len > c->remote_maxpacket)
2959: len = c->remote_maxpacket;
2960: if (len == 0)
1.433 djm 2961: return 0;
1.367 djm 2962: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2963: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2964: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
1.403 djm 2965: (r = sshpkt_send(ssh)) != 0)
2966: fatal_fr(r, "channel %i: send data", c->self);
1.367 djm 2967: if ((r = sshbuf_consume(c->input, len)) != 0)
1.403 djm 2968: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2969: c->remote_window -= len;
1.433 djm 2970: return 1;
1.41 markus 2971: }
2972:
1.367 djm 2973: /*
2974: * Enqueue data for channels with open c->extended in read mode.
1.433 djm 2975: * Returns non-zero if a packet was enqueued.
1.367 djm 2976: */
1.433 djm 2977: static int
1.367 djm 2978: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2979: {
2980: size_t len;
2981: int r;
2982:
2983: if ((len = sshbuf_len(c->extended)) == 0)
1.433 djm 2984: return 0;
1.367 djm 2985:
2986: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2987: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2988: if (len > c->remote_window)
2989: len = c->remote_window;
2990: if (len > c->remote_maxpacket)
2991: len = c->remote_maxpacket;
2992: if (len == 0)
1.433 djm 2993: return 0;
1.368 djm 2994: if (!c->have_remote_id)
1.403 djm 2995: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2996: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2997: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2998: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2999: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
1.403 djm 3000: (r = sshpkt_send(ssh)) != 0)
3001: fatal_fr(r, "channel %i: data", c->self);
1.367 djm 3002: if ((r = sshbuf_consume(c->extended, len)) != 0)
1.403 djm 3003: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 3004: c->remote_window -= len;
3005: debug2("channel %d: sent ext data %zu", c->self, len);
1.433 djm 3006: return 1;
1.367 djm 3007: }
1.121 markus 3008:
1.433 djm 3009: /*
3010: * If there is data to send to the connection, enqueue some of it now.
3011: * Returns non-zero if data was enqueued.
3012: */
3013: int
1.367 djm 3014: channel_output_poll(struct ssh *ssh)
1.1 deraadt 3015: {
1.367 djm 3016: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 3017: Channel *c;
1.367 djm 3018: u_int i;
1.433 djm 3019: int ret = 0;
1.1 deraadt 3020:
1.367 djm 3021: for (i = 0; i < sc->channels_alloc; i++) {
3022: c = sc->channels[i];
1.113 markus 3023: if (c == NULL)
3024: continue;
1.37 markus 3025:
1.121 markus 3026: /*
3027: * We are only interested in channels that can have buffered
3028: * incoming data.
3029: */
1.358 djm 3030: if (c->type != SSH_CHANNEL_OPEN)
3031: continue;
3032: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 3033: /* XXX is this true? */
1.367 djm 3034: debug3("channel %d: will not send data after close",
3035: c->self);
1.44 markus 3036: continue;
3037: }
1.25 markus 3038:
3039: /* Get the amount of buffered data for this channel. */
1.367 djm 3040: if (c->istate == CHAN_INPUT_OPEN ||
3041: c->istate == CHAN_INPUT_WAIT_DRAIN)
1.433 djm 3042: ret |= channel_output_poll_input_open(ssh, c);
1.44 markus 3043: /* Send extended data, i.e. stderr */
1.358 djm 3044: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 3045: c->extended_usage == CHAN_EXTENDED_READ)
1.433 djm 3046: ret |= channel_output_poll_extended_read(ssh, c);
1.25 markus 3047: }
1.433 djm 3048: return ret;
1.1 deraadt 3049: }
3050:
1.354 markus 3051: /* -- mux proxy support */
3052:
3053: /*
3054: * When multiplexing channel messages for mux clients we have to deal
3055: * with downstream messages from the mux client and upstream messages
3056: * from the ssh server:
3057: * 1) Handling downstream messages is straightforward and happens
3058: * in channel_proxy_downstream():
3059: * - We forward all messages (mostly) unmodified to the server.
3060: * - However, in order to route messages from upstream to the correct
3061: * downstream client, we have to replace the channel IDs used by the
3062: * mux clients with a unique channel ID because the mux clients might
3063: * use conflicting channel IDs.
3064: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
3065: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
3066: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
3067: * with the newly allocated channel ID.
3068: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 3069: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 3070: * is then translated back to the original mux client ID.
3071: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
3072: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
3073: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
3074: * downstream mux client are removed.
3075: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
3076: * requires more work, because they are not addressed to a specific
3077: * channel. E.g. client_request_forwarded_tcpip() needs to figure
3078: * out whether the request is addressed to the local client or a
3079: * specific downstream client based on the listen-address/port.
1.380 djm 3080: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 3081: * not supported as the matching session/channel cannot be identified
3082: * easily.
3083: */
3084:
3085: /*
3086: * receive packets from downstream mux clients:
3087: * channel callback fired on read from mux client, creates
3088: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
3089: * on channel creation.
3090: */
3091: int
1.367 djm 3092: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 3093: {
3094: Channel *c = NULL;
3095: struct sshbuf *original = NULL, *modified = NULL;
3096: const u_char *cp;
3097: char *ctype = NULL, *listen_host = NULL;
3098: u_char type;
3099: size_t have;
1.370 djm 3100: int ret = -1, r;
1.355 djm 3101: u_int id, remote_id, listen_port;
1.354 markus 3102:
1.367 djm 3103: /* sshbuf_dump(downstream->input, stderr); */
3104: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 3105: != 0) {
1.403 djm 3106: error_fr(r, "parse");
1.354 markus 3107: return -1;
3108: }
3109: if (have < 2) {
1.403 djm 3110: error_f("short message");
1.354 markus 3111: return -1;
3112: }
3113: type = cp[1];
3114: /* skip padlen + type */
3115: cp += 2;
3116: have -= 2;
3117: if (ssh_packet_log_type(type))
1.403 djm 3118: debug3_f("channel %u: down->up: type %u",
1.354 markus 3119: downstream->self, type);
3120:
3121: switch (type) {
3122: case SSH2_MSG_CHANNEL_OPEN:
3123: if ((original = sshbuf_from(cp, have)) == NULL ||
3124: (modified = sshbuf_new()) == NULL) {
1.403 djm 3125: error_f("alloc");
1.354 markus 3126: goto out;
3127: }
3128: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
3129: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 3130: error_fr(r, "parse");
1.354 markus 3131: goto out;
3132: }
1.424 djm 3133: c = channel_new(ssh, "mux-proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 3134: -1, -1, -1, 0, 0, 0, ctype, 1);
1.354 markus 3135: c->mux_ctx = downstream; /* point to mux client */
3136: c->mux_downstream_id = id; /* original downstream id */
3137: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
3138: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
3139: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 3140: error_fr(r, "compose");
1.367 djm 3141: channel_free(ssh, c);
1.354 markus 3142: goto out;
3143: }
3144: break;
3145: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3146: /*
3147: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
3148: * need to parse 'remote_id' instead of 'ctype'.
3149: */
3150: if ((original = sshbuf_from(cp, have)) == NULL ||
3151: (modified = sshbuf_new()) == NULL) {
1.403 djm 3152: error_f("alloc");
1.354 markus 3153: goto out;
3154: }
3155: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
3156: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 3157: error_fr(r, "parse");
1.354 markus 3158: goto out;
3159: }
1.424 djm 3160: c = channel_new(ssh, "mux-proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 3161: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
1.354 markus 3162: c->mux_ctx = downstream; /* point to mux client */
3163: c->mux_downstream_id = id;
3164: c->remote_id = remote_id;
1.368 djm 3165: c->have_remote_id = 1;
1.354 markus 3166: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
3167: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
3168: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 3169: error_fr(r, "compose");
1.367 djm 3170: channel_free(ssh, c);
1.354 markus 3171: goto out;
3172: }
3173: break;
3174: case SSH2_MSG_GLOBAL_REQUEST:
3175: if ((original = sshbuf_from(cp, have)) == NULL) {
1.403 djm 3176: error_f("alloc");
1.354 markus 3177: goto out;
3178: }
3179: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
1.403 djm 3180: error_fr(r, "parse");
1.354 markus 3181: goto out;
3182: }
3183: if (strcmp(ctype, "tcpip-forward") != 0) {
1.403 djm 3184: error_f("unsupported request %s", ctype);
1.354 markus 3185: goto out;
3186: }
3187: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
3188: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
3189: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
1.403 djm 3190: error_fr(r, "parse");
1.354 markus 3191: goto out;
3192: }
1.355 djm 3193: if (listen_port > 65535) {
1.403 djm 3194: error_f("tcpip-forward for %s: bad port %u",
3195: listen_host, listen_port);
1.355 djm 3196: goto out;
3197: }
1.354 markus 3198: /* Record that connection to this host/port is permitted. */
1.437 djm 3199: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>",
3200: -1, listen_host, NULL, (int)listen_port, downstream);
1.354 markus 3201: break;
3202: case SSH2_MSG_CHANNEL_CLOSE:
3203: if (have < 4)
3204: break;
3205: remote_id = PEEK_U32(cp);
1.367 djm 3206: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 3207: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 3208: channel_free(ssh, c);
1.354 markus 3209: else
3210: c->flags |= CHAN_CLOSE_SENT;
3211: }
3212: break;
3213: }
3214: if (modified) {
3215: if ((r = sshpkt_start(ssh, type)) != 0 ||
3216: (r = sshpkt_putb(ssh, modified)) != 0 ||
3217: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3218: error_fr(r, "send");
1.354 markus 3219: goto out;
3220: }
3221: } else {
3222: if ((r = sshpkt_start(ssh, type)) != 0 ||
3223: (r = sshpkt_put(ssh, cp, have)) != 0 ||
3224: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3225: error_fr(r, "send");
1.354 markus 3226: goto out;
3227: }
3228: }
3229: ret = 0;
3230: out:
3231: free(ctype);
3232: free(listen_host);
3233: sshbuf_free(original);
3234: sshbuf_free(modified);
3235: return ret;
3236: }
3237:
3238: /*
3239: * receive packets from upstream server and de-multiplex packets
3240: * to correct downstream:
3241: * implemented as a helper for channel input handlers,
3242: * replaces local (proxy) channel ID with downstream channel ID.
3243: */
3244: int
1.363 markus 3245: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 3246: {
3247: struct sshbuf *b = NULL;
3248: Channel *downstream;
3249: const u_char *cp = NULL;
3250: size_t len;
3251: int r;
3252:
3253: /*
3254: * When receiving packets from the peer we need to check whether we
3255: * need to forward the packets to the mux client. In this case we
1.380 djm 3256: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 3257: * so we can cleanup the channel.
3258: */
3259: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
3260: return 0;
3261: if ((downstream = c->mux_ctx) == NULL)
3262: return 0;
3263: switch (type) {
3264: case SSH2_MSG_CHANNEL_CLOSE:
3265: case SSH2_MSG_CHANNEL_DATA:
3266: case SSH2_MSG_CHANNEL_EOF:
3267: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
3268: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3269: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
3270: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
3271: case SSH2_MSG_CHANNEL_SUCCESS:
3272: case SSH2_MSG_CHANNEL_FAILURE:
3273: case SSH2_MSG_CHANNEL_REQUEST:
3274: break;
3275: default:
1.403 djm 3276: debug2_f("channel %u: unsupported type %u", c->self, type);
1.354 markus 3277: return 0;
3278: }
3279: if ((b = sshbuf_new()) == NULL) {
1.403 djm 3280: error_f("alloc reply");
1.354 markus 3281: goto out;
3282: }
3283: /* get remaining payload (after id) */
3284: cp = sshpkt_ptr(ssh, &len);
3285: if (cp == NULL) {
1.403 djm 3286: error_f("no packet");
1.354 markus 3287: goto out;
3288: }
3289: /* translate id and send to muxclient */
3290: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
3291: (r = sshbuf_put_u8(b, type)) != 0 ||
3292: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
3293: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 3294: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.403 djm 3295: error_fr(r, "compose muxclient");
1.354 markus 3296: goto out;
3297: }
3298: /* sshbuf_dump(b, stderr); */
3299: if (ssh_packet_log_type(type))
1.403 djm 3300: debug3_f("channel %u: up->down: type %u", c->self, type);
1.354 markus 3301: out:
3302: /* update state */
3303: switch (type) {
3304: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3305: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 3306: if (cp && len > 4) {
1.354 markus 3307: c->remote_id = PEEK_U32(cp);
1.368 djm 3308: c->have_remote_id = 1;
3309: }
1.354 markus 3310: break;
3311: case SSH2_MSG_CHANNEL_CLOSE:
3312: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 3313: channel_free(ssh, c);
1.354 markus 3314: else
3315: c->flags |= CHAN_CLOSE_RCVD;
3316: break;
3317: }
3318: sshbuf_free(b);
3319: return 1;
3320: }
1.121 markus 3321:
3322: /* -- protocol input */
1.249 djm 3323:
1.367 djm 3324: /* Parse a channel ID from the current packet */
3325: static int
3326: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
3327: {
3328: u_int32_t id;
3329: int r;
3330:
3331: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
1.403 djm 3332: error_r(r, "%s: parse id", where);
1.367 djm 3333: ssh_packet_disconnect(ssh, "Invalid %s message", what);
3334: }
3335: if (id > INT_MAX) {
1.403 djm 3336: error_r(r, "%s: bad channel id %u", where, id);
1.367 djm 3337: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
3338: }
3339: return (int)id;
3340: }
3341:
3342: /* Lookup a channel from an ID in the current packet */
3343: static Channel *
3344: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
3345: {
3346: int id = channel_parse_id(ssh, where, what);
3347: Channel *c;
3348:
3349: if ((c = channel_lookup(ssh, id)) == NULL) {
3350: ssh_packet_disconnect(ssh,
3351: "%s packet referred to nonexistent channel %d", what, id);
3352: }
3353: return c;
3354: }
3355:
1.339 markus 3356: int
1.363 markus 3357: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3358: {
1.332 djm 3359: const u_char *data;
1.367 djm 3360: size_t data_len, win_len;
3361: Channel *c = channel_from_packet_id(ssh, __func__, "data");
3362: int r;
1.25 markus 3363:
1.363 markus 3364: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3365: return 0;
1.25 markus 3366:
3367: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 3368: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 3369: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
3370: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 3371: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 3372: return 0;
1.37 markus 3373:
1.25 markus 3374: /* Get the data. */
1.389 djm 3375: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3376: (r = sshpkt_get_end(ssh)) != 0)
1.403 djm 3377: fatal_fr(r, "channel %i: get data", c->self);
1.367 djm 3378:
1.309 djm 3379: win_len = data_len;
3380: if (c->datagram)
3381: win_len += 4; /* string length header */
1.200 markus 3382:
3383: /*
1.367 djm 3384: * The sending side reduces its window as it sends data, so we
3385: * must 'fake' consumption of the data in order to ensure that window
3386: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 3387: */
1.358 djm 3388: if (c->ostate != CHAN_OUTPUT_OPEN) {
3389: c->local_window -= win_len;
3390: c->local_consumed += win_len;
1.339 markus 3391: return 0;
1.200 markus 3392: }
1.41 markus 3393:
1.358 djm 3394: if (win_len > c->local_maxpacket) {
1.367 djm 3395: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 3396: c->self, win_len, c->local_maxpacket);
1.367 djm 3397: return 0;
1.358 djm 3398: }
3399: if (win_len > c->local_window) {
1.435 djm 3400: c->local_window_exceeded += win_len - c->local_window;
3401: logit("channel %d: rcvd too much data %zu, win %u/%u "
3402: "(excess %u)", c->self, win_len, c->local_window,
3403: c->local_window_max, c->local_window_exceeded);
3404: c->local_window = 0;
3405: /* Allow 10% grace before bringing the hammer down */
3406: if (c->local_window_exceeded > (c->local_window_max / 10)) {
3407: ssh_packet_disconnect(ssh, "channel %d: peer ignored "
3408: "channel window", c->self);
3409: }
3410: } else {
3411: c->local_window -= win_len;
3412: c->local_window_exceeded = 0;
1.44 markus 3413: }
1.358 djm 3414:
1.367 djm 3415: if (c->datagram) {
3416: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
1.403 djm 3417: fatal_fr(r, "channel %i: append datagram", c->self);
1.367 djm 3418: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
1.403 djm 3419: fatal_fr(r, "channel %i: append data", c->self);
1.367 djm 3420:
1.339 markus 3421: return 0;
1.1 deraadt 3422: }
1.121 markus 3423:
1.339 markus 3424: int
1.363 markus 3425: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 3426: {
1.367 djm 3427: const u_char *data;
3428: size_t data_len;
3429: u_int32_t tcode;
3430: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
3431: int r;
1.44 markus 3432:
1.363 markus 3433: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3434: return 0;
1.44 markus 3435: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 3436: logit("channel %d: ext data for non open", c->self);
1.339 markus 3437: return 0;
1.172 markus 3438: }
3439: if (c->flags & CHAN_EOF_RCVD) {
1.404 djm 3440: if (ssh->compat & SSH_BUG_EXTEOF)
1.367 djm 3441: debug("channel %d: accepting ext data after eof",
3442: c->self);
1.172 markus 3443: else
1.367 djm 3444: ssh_packet_disconnect(ssh, "Received extended_data "
3445: "after EOF on channel %d.", c->self);
3446: }
3447:
3448: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
1.403 djm 3449: error_fr(r, "parse tcode");
1.367 djm 3450: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3451: }
3452: if (c->efd == -1 ||
3453: c->extended_usage != CHAN_EXTENDED_WRITE ||
3454: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3455: logit("channel %d: bad ext data", c->self);
1.339 markus 3456: return 0;
1.44 markus 3457: }
1.389 djm 3458: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3459: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3460: error_fr(r, "parse data");
1.367 djm 3461: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3462: }
3463:
1.44 markus 3464: if (data_len > c->local_window) {
1.367 djm 3465: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3466: c->self, data_len, c->local_window);
1.339 markus 3467: return 0;
1.44 markus 3468: }
1.367 djm 3469: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3470: /* XXX sshpkt_getb? */
3471: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
1.403 djm 3472: error_fr(r, "append");
1.44 markus 3473: c->local_window -= data_len;
1.339 markus 3474: return 0;
1.44 markus 3475: }
3476:
1.339 markus 3477: int
1.363 markus 3478: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3479: {
1.367 djm 3480: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3481: int r;
1.367 djm 3482:
1.389 djm 3483: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3484: error_fr(r, "parse data");
1.389 djm 3485: ssh_packet_disconnect(ssh, "Invalid ieof message");
3486: }
1.41 markus 3487:
1.363 markus 3488: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3489: return 0;
1.367 djm 3490: chan_rcvd_ieof(ssh, c);
1.133 markus 3491:
3492: /* XXX force input close */
1.156 markus 3493: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3494: debug("channel %d: FORCE input drain", c->self);
3495: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3496: if (sshbuf_len(c->input) == 0)
3497: chan_ibuf_empty(ssh, c);
1.133 markus 3498: }
1.339 markus 3499: return 0;
1.41 markus 3500: }
1.1 deraadt 3501:
1.339 markus 3502: int
1.363 markus 3503: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3504: {
1.367 djm 3505: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3506: int r;
1.151 markus 3507:
1.363 markus 3508: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3509: return 0;
1.389 djm 3510: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3511: error_fr(r, "parse data");
1.389 djm 3512: ssh_packet_disconnect(ssh, "Invalid oclose message");
3513: }
1.367 djm 3514: chan_rcvd_oclose(ssh, c);
1.339 markus 3515: return 0;
1.1 deraadt 3516: }
3517:
1.339 markus 3518: int
1.363 markus 3519: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3520: {
1.367 djm 3521: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3522: u_int32_t remote_window, remote_maxpacket;
3523: int r;
1.25 markus 3524:
1.363 markus 3525: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3526: return 0;
3527: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3528: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3529: "non-opening channel %d.", c->self);
3530: /*
3531: * Record the remote channel number and mark that the channel
3532: * is now open.
3533: */
1.368 djm 3534: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3535: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3536: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3537: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3538: error_fr(r, "window/maxpacket");
1.389 djm 3539: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3540: }
3541:
1.368 djm 3542: c->have_remote_id = 1;
1.367 djm 3543: c->remote_window = remote_window;
3544: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3545: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3546: if (c->open_confirm) {
1.403 djm 3547: debug2_f("channel %d: callback start", c->self);
1.367 djm 3548: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
1.403 djm 3549: debug2_f("channel %d: callback done", c->self);
1.44 markus 3550: }
1.436 djm 3551: channel_set_used_time(ssh, c);
1.358 djm 3552: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3553: c->remote_window, c->remote_maxpacket);
1.339 markus 3554: return 0;
1.1 deraadt 3555: }
3556:
1.127 itojun 3557: static char *
1.114 markus 3558: reason2txt(int reason)
3559: {
1.143 deraadt 3560: switch (reason) {
1.114 markus 3561: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3562: return "administratively prohibited";
3563: case SSH2_OPEN_CONNECT_FAILED:
3564: return "connect failed";
3565: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3566: return "unknown channel type";
3567: case SSH2_OPEN_RESOURCE_SHORTAGE:
3568: return "resource shortage";
3569: }
1.117 stevesk 3570: return "unknown reason";
1.114 markus 3571: }
3572:
1.339 markus 3573: int
1.363 markus 3574: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3575: {
1.367 djm 3576: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3577: u_int32_t reason;
3578: char *msg = NULL;
3579: int r;
1.25 markus 3580:
1.363 markus 3581: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3582: return 0;
3583: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3584: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3585: "non-opening channel %d.", c->self);
3586: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
1.403 djm 3587: error_fr(r, "parse reason");
1.389 djm 3588: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3589: }
1.378 djm 3590: /* skip language */
3591: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3592: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3593: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3594: error_fr(r, "parse msg/lang");
1.389 djm 3595: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3596: }
1.367 djm 3597: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3598: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3599: free(msg);
3600: if (c->open_confirm) {
1.403 djm 3601: debug2_f("channel %d: callback start", c->self);
1.367 djm 3602: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
1.403 djm 3603: debug2_f("channel %d: callback done", c->self);
1.44 markus 3604: }
1.291 djm 3605: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3606: chan_mark_dead(ssh, c);
1.339 markus 3607: return 0;
1.44 markus 3608: }
3609:
1.339 markus 3610: int
1.363 markus 3611: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3612: {
1.367 djm 3613: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3614: Channel *c;
1.367 djm 3615: u_int32_t adjust;
3616: u_int new_rwin;
3617: int r;
1.1 deraadt 3618:
1.367 djm 3619: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3620: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3621: return 0;
1.372 markus 3622: }
1.367 djm 3623:
1.363 markus 3624: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3625: return 0;
1.389 djm 3626: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3627: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3628: error_fr(r, "parse adjust");
1.389 djm 3629: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3630: }
3631: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3632: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3633: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3634: c->self, adjust, c->remote_window);
3635: }
3636: c->remote_window = new_rwin;
1.339 markus 3637: return 0;
1.121 markus 3638: }
1.1 deraadt 3639:
1.339 markus 3640: int
1.363 markus 3641: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3642: {
1.367 djm 3643: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3644: Channel *c;
3645: struct channel_confirm *cc;
3646:
3647: /* Reset keepalive timeout */
1.389 djm 3648: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3649:
1.403 djm 3650: debug2_f("type %d id %d", type, id);
1.275 djm 3651:
1.367 djm 3652: if ((c = channel_lookup(ssh, id)) == NULL) {
1.403 djm 3653: logit_f("%d: unknown", id);
1.339 markus 3654: return 0;
1.367 djm 3655: }
1.363 markus 3656: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3657: return 0;
1.394 dtucker 3658: if (sshpkt_get_end(ssh) != 0)
1.389 djm 3659: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3660: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3661: return 0;
1.367 djm 3662: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3663: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 3664: freezero(cc, sizeof(*cc));
1.339 markus 3665: return 0;
1.275 djm 3666: }
1.121 markus 3667:
3668: /* -- tcp forwarding */
1.135 markus 3669:
3670: void
1.367 djm 3671: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3672: {
1.367 djm 3673: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3674: }
1.121 markus 3675:
1.312 djm 3676:
3677: /*
3678: * Determine whether or not a port forward listens to loopback, the
3679: * specified address or wildcard. On the client, a specified bind
3680: * address will always override gateway_ports. On the server, a
3681: * gateway_ports of 1 (``yes'') will override the client's specification
3682: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3683: * will bind to whatever address the client asked for.
3684: *
3685: * Special-case listen_addrs are:
3686: *
3687: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3688: * "" (empty string), "*" -> wildcard v4/v6
3689: * "localhost" -> loopback v4/v6
1.334 djm 3690: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3691: */
3692: static const char *
1.389 djm 3693: channel_fwd_bind_addr(struct ssh *ssh, const char *listen_addr, int *wildcardp,
1.336 millert 3694: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3695: {
3696: const char *addr = NULL;
3697: int wildcard = 0;
3698:
3699: if (listen_addr == NULL) {
3700: /* No address specified: default to gateway_ports setting */
1.336 millert 3701: if (fwd_opts->gateway_ports)
1.312 djm 3702: wildcard = 1;
1.336 millert 3703: } else if (fwd_opts->gateway_ports || is_client) {
1.404 djm 3704: if (((ssh->compat & SSH_OLD_FORWARD_ADDR) &&
1.312 djm 3705: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3706: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3707: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3708: wildcard = 1;
1.326 djm 3709: /*
3710: * Notify client if they requested a specific listen
3711: * address and it was overridden.
3712: */
3713: if (*listen_addr != '\0' &&
3714: strcmp(listen_addr, "0.0.0.0") != 0 &&
3715: strcmp(listen_addr, "*") != 0) {
1.389 djm 3716: ssh_packet_send_debug(ssh,
3717: "Forwarding listen address "
1.326 djm 3718: "\"%s\" overridden by server "
3719: "GatewayPorts", listen_addr);
3720: }
1.334 djm 3721: } else if (strcmp(listen_addr, "localhost") != 0 ||
3722: strcmp(listen_addr, "127.0.0.1") == 0 ||
3723: strcmp(listen_addr, "::1") == 0) {
1.395 djm 3724: /*
3725: * Accept explicit localhost address when
3726: * GatewayPorts=yes. The "localhost" hostname is
3727: * deliberately skipped here so it will listen on all
3728: * available local address families.
3729: */
1.334 djm 3730: addr = listen_addr;
1.326 djm 3731: }
1.334 djm 3732: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3733: strcmp(listen_addr, "::1") == 0) {
3734: /*
3735: * If a specific IPv4/IPv6 localhost address has been
3736: * requested then accept it even if gateway_ports is in
3737: * effect. This allows the client to prefer IPv4 or IPv6.
3738: */
3739: addr = listen_addr;
1.312 djm 3740: }
3741: if (wildcardp != NULL)
3742: *wildcardp = wildcard;
3743: return addr;
3744: }
3745:
1.160 markus 3746: static int
1.367 djm 3747: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3748: struct Forward *fwd, int *allocated_listen_port,
3749: struct ForwardOptions *fwd_opts)
1.25 markus 3750: {
1.113 markus 3751: Channel *c;
1.226 djm 3752: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3753: struct addrinfo hints, *ai, *aitop;
1.212 djm 3754: const char *host, *addr;
1.35 markus 3755: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3756: in_port_t *lport_p;
1.25 markus 3757:
1.212 djm 3758: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3759:
1.344 millert 3760: if (is_client && fwd->connect_path != NULL) {
3761: host = fwd->connect_path;
3762: } else {
3763: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3764: fwd->listen_host : fwd->connect_host;
3765: if (host == NULL) {
3766: error("No forward host name.");
3767: return 0;
3768: }
3769: if (strlen(host) >= NI_MAXHOST) {
3770: error("Forward host name too long.");
3771: return 0;
3772: }
1.87 markus 3773: }
1.25 markus 3774:
1.312 djm 3775: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3776: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3777: is_client, fwd_opts);
1.403 djm 3778: debug3_f("type %d wildcard %d addr %s", type, wildcard,
3779: (addr == NULL) ? "NULL" : addr);
1.212 djm 3780:
3781: /*
1.35 markus 3782: * getaddrinfo returns a loopback address if the hostname is
3783: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3784: */
1.35 markus 3785: memset(&hints, 0, sizeof(hints));
1.367 djm 3786: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3787: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3788: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3789: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3790: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3791: if (addr == NULL) {
3792: /* This really shouldn't happen */
1.389 djm 3793: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3794: ssh_gai_strerror(r));
1.212 djm 3795: } else {
1.403 djm 3796: error_f("getaddrinfo(%.64s): %s", addr,
1.271 dtucker 3797: ssh_gai_strerror(r));
1.212 djm 3798: }
1.218 markus 3799: return 0;
1.212 djm 3800: }
1.295 djm 3801: if (allocated_listen_port != NULL)
3802: *allocated_listen_port = 0;
1.35 markus 3803: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3804: switch (ai->ai_family) {
3805: case AF_INET:
3806: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3807: sin_port;
3808: break;
3809: case AF_INET6:
3810: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3811: sin6_port;
3812: break;
3813: default:
1.35 markus 3814: continue;
1.295 djm 3815: }
3816: /*
3817: * If allocating a port for -R forwards, then use the
3818: * same port for all address families.
3819: */
1.367 djm 3820: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3821: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3822: *allocated_listen_port > 0)
1.295 djm 3823: *lport_p = htons(*allocated_listen_port);
3824:
1.35 markus 3825: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3826: strport, sizeof(strport),
3827: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.403 djm 3828: error_f("getnameinfo failed");
1.35 markus 3829: continue;
3830: }
3831: /* Create a port to listen for the host. */
1.300 dtucker 3832: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 3833: if (sock == -1) {
1.35 markus 3834: /* this is no error since kernel may not support ipv6 */
1.377 djm 3835: verbose("socket [%s]:%s: %.100s", ntop, strport,
3836: strerror(errno));
1.35 markus 3837: continue;
3838: }
1.226 djm 3839:
1.376 djm 3840: set_reuseaddr(sock);
1.182 stevesk 3841:
1.295 djm 3842: debug("Local forwarding listening on %s port %s.",
3843: ntop, strport);
1.35 markus 3844:
3845: /* Bind the socket to the address. */
1.393 deraadt 3846: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3847: /*
3848: * address can be in if use ipv6 address is
3849: * already bound
3850: */
1.377 djm 3851: verbose("bind [%s]:%s: %.100s",
3852: ntop, strport, strerror(errno));
1.35 markus 3853: close(sock);
3854: continue;
3855: }
3856: /* Start listening for connections on the socket. */
1.393 deraadt 3857: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3858: error("listen [%s]:%s: %.100s", ntop, strport,
3859: strerror(errno));
1.35 markus 3860: close(sock);
3861: continue;
3862: }
1.295 djm 3863:
3864: /*
1.336 millert 3865: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3866: * record what we got.
3867: */
1.367 djm 3868: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3869: fwd->listen_port == 0 &&
1.295 djm 3870: allocated_listen_port != NULL &&
3871: *allocated_listen_port == 0) {
1.350 djm 3872: *allocated_listen_port = get_local_port(sock);
1.295 djm 3873: debug("Allocated listen port %d",
3874: *allocated_listen_port);
3875: }
3876:
1.35 markus 3877: /* Allocate a channel number for the socket. */
1.424 djm 3878: c = channel_new(ssh, "port-listener", type, sock, sock, -1,
1.51 markus 3879: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3880: 0, "port listener", 1);
1.293 djm 3881: c->path = xstrdup(host);
1.336 millert 3882: c->host_port = fwd->connect_port;
1.312 djm 3883: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3884: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.404 djm 3885: !(ssh->compat & SSH_BUG_DYNAMIC_RPORT))
1.315 markus 3886: c->listening_port = *allocated_listen_port;
3887: else
1.336 millert 3888: c->listening_port = fwd->listen_port;
1.35 markus 3889: success = 1;
3890: }
3891: if (success == 0)
1.403 djm 3892: error_f("cannot listen to port: %d", fwd->listen_port);
1.35 markus 3893: freeaddrinfo(aitop);
1.87 markus 3894: return success;
1.25 markus 3895: }
1.1 deraadt 3896:
1.336 millert 3897: static int
1.367 djm 3898: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3899: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3900: {
3901: struct sockaddr_un sunaddr;
3902: const char *path;
3903: Channel *c;
3904: int port, sock;
3905: mode_t omask;
3906:
3907: switch (type) {
3908: case SSH_CHANNEL_UNIX_LISTENER:
3909: if (fwd->connect_path != NULL) {
3910: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3911: error("Local connecting path too long: %s",
3912: fwd->connect_path);
3913: return 0;
3914: }
3915: path = fwd->connect_path;
3916: port = PORT_STREAMLOCAL;
3917: } else {
3918: if (fwd->connect_host == NULL) {
3919: error("No forward host name.");
3920: return 0;
3921: }
3922: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3923: error("Forward host name too long.");
3924: return 0;
3925: }
3926: path = fwd->connect_host;
3927: port = fwd->connect_port;
3928: }
3929: break;
3930: case SSH_CHANNEL_RUNIX_LISTENER:
3931: path = fwd->listen_path;
3932: port = PORT_STREAMLOCAL;
3933: break;
3934: default:
1.403 djm 3935: error_f("unexpected channel type %d", type);
1.336 millert 3936: return 0;
3937: }
3938:
3939: if (fwd->listen_path == NULL) {
3940: error("No forward path name.");
3941: return 0;
3942: }
3943: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3944: error("Local listening path too long: %s", fwd->listen_path);
3945: return 0;
3946: }
3947:
1.403 djm 3948: debug3_f("type %d path %s", type, fwd->listen_path);
1.336 millert 3949:
3950: /* Start a Unix domain listener. */
3951: omask = umask(fwd_opts->streamlocal_bind_mask);
3952: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3953: fwd_opts->streamlocal_bind_unlink);
3954: umask(omask);
3955: if (sock < 0)
3956: return 0;
3957:
3958: debug("Local forwarding listening on path %s.", fwd->listen_path);
3959:
3960: /* Allocate a channel number for the socket. */
1.424 djm 3961: c = channel_new(ssh, "unix-listener", type, sock, sock, -1,
1.336 millert 3962: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3963: 0, "unix listener", 1);
3964: c->path = xstrdup(path);
3965: c->host_port = port;
3966: c->listening_port = PORT_STREAMLOCAL;
3967: c->listening_addr = xstrdup(fwd->listen_path);
3968: return 1;
3969: }
3970:
3971: static int
1.367 djm 3972: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3973: const char *host, u_short port)
1.202 djm 3974: {
1.209 avsm 3975: u_int i;
3976: int found = 0;
1.202 djm 3977:
1.367 djm 3978: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3979: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3980: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3981: continue;
3982: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
1.403 djm 3983: debug2_f("close channel %d", i);
1.367 djm 3984: channel_free(ssh, c);
1.312 djm 3985: found = 1;
3986: }
3987: }
3988:
1.367 djm 3989: return found;
1.312 djm 3990: }
3991:
1.336 millert 3992: static int
1.367 djm 3993: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3994: {
3995: u_int i;
3996: int found = 0;
3997:
1.367 djm 3998: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3999: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 4000: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
4001: continue;
4002: if (c->path == NULL)
4003: continue;
4004: if (strcmp(c->path, path) == 0) {
1.403 djm 4005: debug2_f("close channel %d", i);
1.367 djm 4006: channel_free(ssh, c);
1.336 millert 4007: found = 1;
4008: }
4009: }
4010:
1.367 djm 4011: return found;
1.336 millert 4012: }
4013:
1.312 djm 4014: int
1.367 djm 4015: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 4016: {
1.367 djm 4017: if (fwd->listen_path != NULL) {
4018: return channel_cancel_rport_listener_streamlocal(ssh,
4019: fwd->listen_path);
4020: } else {
4021: return channel_cancel_rport_listener_tcpip(ssh,
4022: fwd->listen_host, fwd->listen_port);
4023: }
1.336 millert 4024: }
4025:
4026: static int
1.367 djm 4027: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
4028: const char *lhost, u_short lport, int cport,
4029: struct ForwardOptions *fwd_opts)
1.312 djm 4030: {
4031: u_int i;
4032: int found = 0;
1.389 djm 4033: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 4034:
1.367 djm 4035: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
4036: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 4037: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
4038: continue;
1.313 markus 4039: if (c->listening_port != lport)
1.312 djm 4040: continue;
1.313 markus 4041: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
4042: /* skip dynamic forwardings */
4043: if (c->host_port == 0)
4044: continue;
4045: } else {
4046: if (c->host_port != cport)
4047: continue;
4048: }
1.312 djm 4049: if ((c->listening_addr == NULL && addr != NULL) ||
4050: (c->listening_addr != NULL && addr == NULL))
4051: continue;
4052: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.403 djm 4053: debug2_f("close channel %d", i);
1.367 djm 4054: channel_free(ssh, c);
1.202 djm 4055: found = 1;
4056: }
4057: }
4058:
1.367 djm 4059: return found;
1.202 djm 4060: }
4061:
1.336 millert 4062: static int
1.367 djm 4063: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 4064: {
4065: u_int i;
4066: int found = 0;
4067:
4068: if (path == NULL) {
1.403 djm 4069: error_f("no path specified.");
1.336 millert 4070: return 0;
4071: }
4072:
1.367 djm 4073: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
4074: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 4075: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
4076: continue;
4077: if (c->listening_addr == NULL)
4078: continue;
4079: if (strcmp(c->listening_addr, path) == 0) {
1.403 djm 4080: debug2_f("close channel %d", i);
1.367 djm 4081: channel_free(ssh, c);
1.336 millert 4082: found = 1;
4083: }
4084: }
4085:
1.367 djm 4086: return found;
1.336 millert 4087: }
4088:
4089: int
1.367 djm 4090: channel_cancel_lport_listener(struct ssh *ssh,
4091: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 4092: {
1.367 djm 4093: if (fwd->listen_path != NULL) {
4094: return channel_cancel_lport_listener_streamlocal(ssh,
4095: fwd->listen_path);
4096: } else {
4097: return channel_cancel_lport_listener_tcpip(ssh,
4098: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
4099: }
1.336 millert 4100: }
4101:
1.362 markus 4102: /* protocol local port fwd, used by ssh */
1.160 markus 4103: int
1.367 djm 4104: channel_setup_local_fwd_listener(struct ssh *ssh,
4105: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 4106: {
1.336 millert 4107: if (fwd->listen_path != NULL) {
1.367 djm 4108: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 4109: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
4110: } else {
1.367 djm 4111: return channel_setup_fwd_listener_tcpip(ssh,
4112: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 4113: }
1.160 markus 4114: }
4115:
1.381 djm 4116: /* Matches a remote forwarding permission against a requested forwarding */
4117: static int
4118: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
4119: {
4120: int ret;
4121: char *lhost;
4122:
4123: /* XXX add ACLs for streamlocal */
4124: if (fwd->listen_path != NULL)
4125: return 1;
4126:
4127: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
4128: return 0;
4129:
4130: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
4131: allowed_open->listen_port != fwd->listen_port)
4132: return 0;
4133:
4134: /* Match hostnames case-insensitively */
4135: lhost = xstrdup(fwd->listen_host);
4136: lowercase(lhost);
4137: ret = match_pattern(lhost, allowed_open->listen_host);
4138: free(lhost);
4139:
4140: return ret;
4141: }
4142:
4143: /* Checks whether a requested remote forwarding is permitted */
4144: static int
4145: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
4146: {
4147: struct ssh_channels *sc = ssh->chanctxt;
4148: struct permission_set *pset = &sc->remote_perms;
4149: u_int i, permit, permit_adm = 1;
4150: struct permission *perm;
4151:
4152: /* XXX apply GatewayPorts override before checking? */
4153:
4154: permit = pset->all_permitted;
4155: if (!permit) {
4156: for (i = 0; i < pset->num_permitted_user; i++) {
4157: perm = &pset->permitted_user[i];
4158: if (remote_open_match(perm, fwd)) {
4159: permit = 1;
4160: break;
4161: }
4162: }
4163: }
4164:
4165: if (pset->num_permitted_admin > 0) {
4166: permit_adm = 0;
4167: for (i = 0; i < pset->num_permitted_admin; i++) {
4168: perm = &pset->permitted_admin[i];
4169: if (remote_open_match(perm, fwd)) {
4170: permit_adm = 1;
4171: break;
4172: }
4173: }
4174: }
4175:
4176: return permit && permit_adm;
4177: }
4178:
1.160 markus 4179: /* protocol v2 remote port fwd, used by sshd */
4180: int
1.367 djm 4181: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 4182: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 4183: {
1.381 djm 4184: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 4185: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 4186: if (fwd->listen_path != NULL)
4187: /* XXX always allowed, see remote_open_match() */
4188: logit("Received request from %.100s port %d to "
4189: "remote forward to path \"%.100s\", "
4190: "but the request was denied.",
4191: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
4192: fwd->listen_path);
4193: else if(fwd->listen_host != NULL)
4194: logit("Received request from %.100s port %d to "
4195: "remote forward to host %.100s port %d, "
4196: "but the request was denied.",
4197: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
4198: fwd->listen_host, fwd->listen_port );
4199: else
4200: logit("Received request from %.100s port %d to remote "
4201: "forward, but the request was denied.",
4202: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 4203: return 0;
4204: }
1.336 millert 4205: if (fwd->listen_path != NULL) {
1.367 djm 4206: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 4207: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
4208: } else {
1.367 djm 4209: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 4210: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
4211: fwd_opts);
4212: }
1.160 markus 4213: }
4214:
1.27 markus 4215: /*
1.312 djm 4216: * Translate the requested rfwd listen host to something usable for
4217: * this server.
4218: */
4219: static const char *
4220: channel_rfwd_bind_host(const char *listen_host)
4221: {
4222: if (listen_host == NULL) {
1.378 djm 4223: return "localhost";
1.312 djm 4224: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 4225: return "";
1.312 djm 4226: } else
4227: return listen_host;
4228: }
4229:
4230: /*
1.27 markus 4231: * Initiate forwarding of connections to port "port" on remote host through
4232: * the secure channel to host:port from local side.
1.315 markus 4233: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 4234: * channel_update_permission().
1.27 markus 4235: */
1.253 markus 4236: int
1.367 djm 4237: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 4238: {
1.367 djm 4239: int r, success = 0, idx = -1;
1.421 mbuhl 4240: const char *host_to_connect, *listen_host, *listen_path;
1.367 djm 4241: int port_to_connect, listen_port;
1.73 markus 4242:
1.25 markus 4243: /* Send the forward request to the remote side. */
1.358 djm 4244: if (fwd->listen_path != NULL) {
1.367 djm 4245: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4246: (r = sshpkt_put_cstring(ssh,
4247: "streamlocal-forward@openssh.com")) != 0 ||
4248: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4249: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
4250: (r = sshpkt_send(ssh)) != 0 ||
4251: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4252: fatal_fr(r, "request streamlocal");
1.336 millert 4253: } else {
1.367 djm 4254: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4255: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
4256: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4257: (r = sshpkt_put_cstring(ssh,
4258: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
4259: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
4260: (r = sshpkt_send(ssh)) != 0 ||
4261: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4262: fatal_fr(r, "request tcpip-forward");
1.73 markus 4263: }
1.358 djm 4264: /* Assume that server accepts the request */
4265: success = 1;
1.73 markus 4266: if (success) {
1.305 djm 4267: /* Record that connection to this host/port is permitted. */
1.367 djm 4268: host_to_connect = listen_host = listen_path = NULL;
4269: port_to_connect = listen_port = 0;
1.336 millert 4270: if (fwd->connect_path != NULL) {
1.421 mbuhl 4271: host_to_connect = fwd->connect_path;
1.367 djm 4272: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 4273: } else {
1.421 mbuhl 4274: host_to_connect = fwd->connect_host;
1.367 djm 4275: port_to_connect = fwd->connect_port;
1.336 millert 4276: }
4277: if (fwd->listen_path != NULL) {
1.421 mbuhl 4278: listen_path = fwd->listen_path;
1.367 djm 4279: listen_port = PORT_STREAMLOCAL;
1.336 millert 4280: } else {
1.421 mbuhl 4281: listen_host = fwd->listen_host;
1.367 djm 4282: listen_port = fwd->listen_port;
4283: }
1.381 djm 4284: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 4285: host_to_connect, port_to_connect,
4286: listen_host, listen_path, listen_port, NULL);
1.44 markus 4287: }
1.367 djm 4288: return idx;
1.1 deraadt 4289: }
4290:
1.333 markus 4291: static int
1.381 djm 4292: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 4293: int requestedport)
1.333 markus 4294: {
4295: if (allowed_open->host_to_connect == NULL)
4296: return 0;
4297: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
4298: allowed_open->port_to_connect != requestedport)
4299: return 0;
1.351 dtucker 4300: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
4301: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 4302: return 0;
4303: return 1;
4304: }
4305:
4306: /*
1.336 millert 4307: * Note that in the listen host/port case
1.333 markus 4308: * we don't support FWD_PERMIT_ANY_PORT and
4309: * need to translate between the configured-host (listen_host)
4310: * and what we've sent to the remote server (channel_rfwd_bind_host)
4311: */
4312: static int
1.381 djm 4313: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 4314: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 4315: {
4316: const char *allowed_host;
4317:
4318: if (allowed_open->host_to_connect == NULL)
4319: return 0;
4320: if (allowed_open->listen_port != requestedport)
4321: return 0;
1.335 djm 4322: if (!translate && allowed_open->listen_host == NULL &&
4323: requestedhost == NULL)
4324: return 1;
1.333 markus 4325: allowed_host = translate ?
4326: channel_rfwd_bind_host(allowed_open->listen_host) :
4327: allowed_open->listen_host;
1.382 djm 4328: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 4329: strcmp(allowed_host, requestedhost) != 0)
4330: return 0;
4331: return 1;
4332: }
4333:
1.336 millert 4334: static int
1.381 djm 4335: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 4336: const char *requestedpath)
4337: {
4338: if (allowed_open->host_to_connect == NULL)
4339: return 0;
4340: if (allowed_open->listen_port != PORT_STREAMLOCAL)
4341: return 0;
4342: if (allowed_open->listen_path == NULL ||
4343: strcmp(allowed_open->listen_path, requestedpath) != 0)
4344: return 0;
4345: return 1;
4346: }
4347:
1.27 markus 4348: /*
1.208 deraadt 4349: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 4350: * local side.
4351: */
1.336 millert 4352: static int
1.367 djm 4353: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
4354: const char *host, u_short port)
1.202 djm 4355: {
1.367 djm 4356: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4357: struct permission_set *pset = &sc->local_perms;
1.367 djm 4358: int r;
4359: u_int i;
1.397 markus 4360: struct permission *perm = NULL;
1.202 djm 4361:
1.381 djm 4362: for (i = 0; i < pset->num_permitted_user; i++) {
4363: perm = &pset->permitted_user[i];
4364: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 4365: break;
1.381 djm 4366: perm = NULL;
1.202 djm 4367: }
1.381 djm 4368: if (perm == NULL) {
1.403 djm 4369: debug_f("requested forward not found");
1.312 djm 4370: return -1;
1.202 djm 4371: }
1.367 djm 4372: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4373: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
4374: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4375: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
4376: (r = sshpkt_put_u32(ssh, port)) != 0 ||
4377: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4378: fatal_fr(r, "send cancel");
1.367 djm 4379:
1.381 djm 4380: fwd_perm_clear(perm); /* unregister */
1.336 millert 4381:
4382: return 0;
4383: }
4384:
4385: /*
4386: * Request cancellation of remote forwarding of Unix domain socket
4387: * path from local side.
4388: */
4389: static int
1.367 djm 4390: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 4391: {
1.367 djm 4392: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4393: struct permission_set *pset = &sc->local_perms;
1.367 djm 4394: int r;
4395: u_int i;
1.397 markus 4396: struct permission *perm = NULL;
1.336 millert 4397:
1.381 djm 4398: for (i = 0; i < pset->num_permitted_user; i++) {
4399: perm = &pset->permitted_user[i];
4400: if (open_listen_match_streamlocal(perm, path))
1.336 millert 4401: break;
1.381 djm 4402: perm = NULL;
1.336 millert 4403: }
1.381 djm 4404: if (perm == NULL) {
1.403 djm 4405: debug_f("requested forward not found");
1.336 millert 4406: return -1;
4407: }
1.367 djm 4408: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4409: (r = sshpkt_put_cstring(ssh,
4410: "cancel-streamlocal-forward@openssh.com")) != 0 ||
4411: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4412: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
4413: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4414: fatal_fr(r, "send cancel");
1.367 djm 4415:
1.381 djm 4416: fwd_perm_clear(perm); /* unregister */
1.312 djm 4417:
4418: return 0;
1.202 djm 4419: }
4420:
4421: /*
1.336 millert 4422: * Request cancellation of remote forwarding of a connection from local side.
4423: */
4424: int
1.367 djm 4425: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 4426: {
4427: if (fwd->listen_path != NULL) {
1.367 djm 4428: return channel_request_rforward_cancel_streamlocal(ssh,
4429: fwd->listen_path);
1.336 millert 4430: } else {
1.367 djm 4431: return channel_request_rforward_cancel_tcpip(ssh,
4432: fwd->listen_host,
4433: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 4434: }
1.1 deraadt 4435: }
4436:
1.99 markus 4437: /*
1.381 djm 4438: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 4439: * usually called by the server, because the user could connect to any port
4440: * anyway, and the server has no way to know but to trust the client anyway.
4441: */
4442: void
1.381 djm 4443: channel_permit_all(struct ssh *ssh, int where)
4444: {
4445: struct permission_set *pset = permission_set_get(ssh, where);
4446:
4447: if (pset->num_permitted_user == 0)
4448: pset->all_permitted = 1;
4449: }
4450:
4451: /*
4452: * Permit the specified host/port for forwarding.
4453: */
4454: void
4455: channel_add_permission(struct ssh *ssh, int who, int where,
4456: char *host, int port)
4457: {
4458: int local = where == FORWARD_LOCAL;
4459: struct permission_set *pset = permission_set_get(ssh, where);
4460:
4461: debug("allow %s forwarding to host %s port %d",
4462: fwd_ident(who, where), host, port);
4463: /*
4464: * Remote forwards set listen_host/port, local forwards set
4465: * host/port_to_connect.
4466: */
4467: permission_set_add(ssh, who, where,
4468: local ? host : 0, local ? port : 0,
4469: local ? NULL : host, NULL, local ? 0 : port, NULL);
4470: pset->all_permitted = 0;
4471: }
4472:
4473: /*
4474: * Administratively disable forwarding.
4475: */
4476: void
4477: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4478: {
1.381 djm 4479: channel_clear_permission(ssh, FORWARD_ADM, where);
4480: permission_set_add(ssh, FORWARD_ADM, where,
4481: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4482: }
4483:
1.381 djm 4484: /*
4485: * Clear a list of permitted opens.
4486: */
1.101 markus 4487: void
1.381 djm 4488: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4489: {
1.381 djm 4490: struct permission **permp;
4491: u_int *npermp;
1.367 djm 4492:
1.381 djm 4493: permission_set_get_array(ssh, who, where, &permp, &npermp);
4494: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4495: *npermp = 0;
1.315 markus 4496: }
4497:
4498: /*
4499: * Update the listen port for a dynamic remote forward, after
4500: * the actual 'newport' has been allocated. If 'newport' < 0 is
4501: * passed then they entry will be invalidated.
4502: */
4503: void
1.381 djm 4504: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4505: {
1.381 djm 4506: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4507:
1.381 djm 4508: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
1.403 djm 4509: debug_f("index out of range: %d num_permitted_user %d",
4510: idx, pset->num_permitted_user);
1.315 markus 4511: return;
4512: }
4513: debug("%s allowed port %d for forwarding to host %s port %d",
4514: newport > 0 ? "Updating" : "Removing",
4515: newport,
1.381 djm 4516: pset->permitted_user[idx].host_to_connect,
4517: pset->permitted_user[idx].port_to_connect);
1.367 djm 4518: if (newport <= 0)
1.381 djm 4519: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4520: else {
1.381 djm 4521: pset->permitted_user[idx].listen_port =
1.404 djm 4522: (ssh->compat & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
1.315 markus 4523: }
1.314 dtucker 4524: }
4525:
1.276 djm 4526: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4527: static int
1.276 djm 4528: connect_next(struct channel_connect *cctx)
1.41 markus 4529: {
1.276 djm 4530: int sock, saved_errno;
1.336 millert 4531: struct sockaddr_un *sunaddr;
1.367 djm 4532: char ntop[NI_MAXHOST];
4533: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4534:
1.276 djm 4535: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4536: switch (cctx->ai->ai_family) {
4537: case AF_UNIX:
4538: /* unix:pathname instead of host:port */
4539: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4540: strlcpy(ntop, "unix", sizeof(ntop));
4541: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4542: break;
4543: case AF_INET:
4544: case AF_INET6:
4545: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4546: ntop, sizeof(ntop), strport, sizeof(strport),
4547: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.420 djm 4548: error_f("getnameinfo failed");
1.336 millert 4549: continue;
4550: }
4551: break;
4552: default:
1.41 markus 4553: continue;
4554: }
1.420 djm 4555: debug_f("start for host %.100s ([%.100s]:%s)",
4556: cctx->host, ntop, strport);
1.300 dtucker 4557: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4558: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4559: if (cctx->ai->ai_next == NULL)
1.186 djm 4560: error("socket: %.100s", strerror(errno));
4561: else
4562: verbose("socket: %.100s", strerror(errno));
1.41 markus 4563: continue;
4564: }
1.205 djm 4565: if (set_nonblock(sock) == -1)
1.403 djm 4566: fatal_f("set_nonblock(%d)", sock);
1.276 djm 4567: if (connect(sock, cctx->ai->ai_addr,
4568: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
1.420 djm 4569: debug_f("host %.100s ([%.100s]:%s): %.100s",
4570: cctx->host, ntop, strport, strerror(errno));
1.276 djm 4571: saved_errno = errno;
1.41 markus 4572: close(sock);
1.276 djm 4573: errno = saved_errno;
1.89 stevesk 4574: continue; /* fail -- try next */
1.41 markus 4575: }
1.336 millert 4576: if (cctx->ai->ai_family != AF_UNIX)
4577: set_nodelay(sock);
1.420 djm 4578: debug_f("connect host %.100s ([%.100s]:%s) in progress, fd=%d",
4579: cctx->host, ntop, strport, sock);
1.276 djm 4580: cctx->ai = cctx->ai->ai_next;
4581: return sock;
4582: }
4583: return -1;
4584: }
1.41 markus 4585:
1.276 djm 4586: static void
4587: channel_connect_ctx_free(struct channel_connect *cctx)
4588: {
1.321 djm 4589: free(cctx->host);
1.336 millert 4590: if (cctx->aitop) {
4591: if (cctx->aitop->ai_family == AF_UNIX)
4592: free(cctx->aitop);
4593: else
4594: freeaddrinfo(cctx->aitop);
4595: }
1.329 tedu 4596: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4597: }
4598:
1.357 dtucker 4599: /*
1.372 markus 4600: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4601: * passing back the failure reason if appropriate.
4602: */
1.372 markus 4603: static int
4604: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4605: char *ctype, char *rname, struct channel_connect *cctx,
4606: int *reason, const char **errmsg)
1.276 djm 4607: {
4608: struct addrinfo hints;
4609: int gaierr;
4610: int sock = -1;
4611: char strport[NI_MAXSERV];
1.336 millert 4612:
4613: if (port == PORT_STREAMLOCAL) {
4614: struct sockaddr_un *sunaddr;
4615: struct addrinfo *ai;
4616:
4617: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4618: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4619: return -1;
1.336 millert 4620: }
4621:
4622: /*
4623: * Fake up a struct addrinfo for AF_UNIX connections.
4624: * channel_connect_ctx_free() must check ai_family
4625: * and use free() not freeaddirinfo() for AF_UNIX.
4626: */
4627: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4628: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4629: ai->ai_addr = (struct sockaddr *)(ai + 1);
4630: ai->ai_addrlen = sizeof(*sunaddr);
4631: ai->ai_family = AF_UNIX;
1.372 markus 4632: ai->ai_socktype = socktype;
1.336 millert 4633: ai->ai_protocol = PF_UNSPEC;
4634: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4635: sunaddr->sun_family = AF_UNIX;
4636: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4637: cctx->aitop = ai;
1.336 millert 4638: } else {
4639: memset(&hints, 0, sizeof(hints));
1.367 djm 4640: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4641: hints.ai_socktype = socktype;
1.336 millert 4642: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4643: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4644: != 0) {
4645: if (errmsg != NULL)
4646: *errmsg = ssh_gai_strerror(gaierr);
4647: if (reason != NULL)
4648: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4649: error("connect_to %.100s: unknown host (%s)", name,
4650: ssh_gai_strerror(gaierr));
1.372 markus 4651: return -1;
1.336 millert 4652: }
1.41 markus 4653: }
1.276 djm 4654:
1.372 markus 4655: cctx->host = xstrdup(name);
4656: cctx->port = port;
4657: cctx->ai = cctx->aitop;
1.276 djm 4658:
1.372 markus 4659: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4660: error("connect to %.100s port %d failed: %s",
1.336 millert 4661: name, port, strerror(errno));
1.372 markus 4662: return -1;
4663: }
4664:
4665: return sock;
4666: }
4667:
4668: /* Return CONNECTING channel to remote host:port or local socket path */
4669: static Channel *
4670: connect_to(struct ssh *ssh, const char *host, int port,
4671: char *ctype, char *rname)
4672: {
4673: struct channel_connect cctx;
4674: Channel *c;
4675: int sock;
4676:
4677: memset(&cctx, 0, sizeof(cctx));
4678: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4679: &cctx, NULL, NULL);
4680: if (sock == -1) {
1.276 djm 4681: channel_connect_ctx_free(&cctx);
4682: return NULL;
1.41 markus 4683: }
1.367 djm 4684: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4685: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4686: c->host_port = port;
4687: c->path = xstrdup(host);
1.276 djm 4688: c->connect_ctx = cctx;
1.372 markus 4689:
1.276 djm 4690: return c;
1.41 markus 4691: }
1.99 markus 4692:
1.354 markus 4693: /*
4694: * returns either the newly connected channel or the downstream channel
4695: * that needs to deal with this connection.
4696: */
1.276 djm 4697: Channel *
1.367 djm 4698: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4699: u_short listen_port, char *ctype, char *rname)
1.73 markus 4700: {
1.367 djm 4701: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4702: struct permission_set *pset = &sc->local_perms;
1.367 djm 4703: u_int i;
1.381 djm 4704: struct permission *perm;
1.99 markus 4705:
1.381 djm 4706: for (i = 0; i < pset->num_permitted_user; i++) {
4707: perm = &pset->permitted_user[i];
4708: if (open_listen_match_tcpip(perm,
4709: listen_host, listen_port, 1)) {
4710: if (perm->downstream)
4711: return perm->downstream;
4712: if (perm->port_to_connect == 0)
1.372 markus 4713: return rdynamic_connect_prepare(ssh,
4714: ctype, rname);
1.367 djm 4715: return connect_to(ssh,
1.381 djm 4716: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4717: ctype, rname);
1.276 djm 4718: }
4719: }
1.74 markus 4720: error("WARNING: Server requests forwarding for unknown listen_port %d",
4721: listen_port);
1.276 djm 4722: return NULL;
1.73 markus 4723: }
4724:
1.336 millert 4725: Channel *
1.367 djm 4726: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4727: char *ctype, char *rname)
1.336 millert 4728: {
1.367 djm 4729: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4730: struct permission_set *pset = &sc->local_perms;
1.367 djm 4731: u_int i;
1.381 djm 4732: struct permission *perm;
1.336 millert 4733:
1.381 djm 4734: for (i = 0; i < pset->num_permitted_user; i++) {
4735: perm = &pset->permitted_user[i];
4736: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4737: return connect_to(ssh,
1.381 djm 4738: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4739: ctype, rname);
1.336 millert 4740: }
4741: }
4742: error("WARNING: Server requests forwarding for unknown path %.100s",
4743: path);
4744: return NULL;
4745: }
4746:
1.99 markus 4747: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4748: Channel *
1.367 djm 4749: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4750: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4751: {
1.367 djm 4752: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4753: struct permission_set *pset = &sc->local_perms;
1.372 markus 4754: struct channel_connect cctx;
4755: Channel *c;
1.367 djm 4756: u_int i, permit, permit_adm = 1;
1.372 markus 4757: int sock;
1.381 djm 4758: struct permission *perm;
1.99 markus 4759:
1.381 djm 4760: permit = pset->all_permitted;
1.99 markus 4761: if (!permit) {
1.381 djm 4762: for (i = 0; i < pset->num_permitted_user; i++) {
4763: perm = &pset->permitted_user[i];
4764: if (open_match(perm, host, port)) {
1.99 markus 4765: permit = 1;
1.333 markus 4766: break;
4767: }
1.367 djm 4768: }
1.257 dtucker 4769: }
1.99 markus 4770:
1.381 djm 4771: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4772: permit_adm = 0;
1.381 djm 4773: for (i = 0; i < pset->num_permitted_admin; i++) {
4774: perm = &pset->permitted_admin[i];
4775: if (open_match(perm, host, port)) {
1.257 dtucker 4776: permit_adm = 1;
1.333 markus 4777: break;
4778: }
1.367 djm 4779: }
1.99 markus 4780: }
1.257 dtucker 4781:
4782: if (!permit || !permit_adm) {
1.391 florian 4783: logit("Received request from %.100s port %d to connect to "
4784: "host %.100s port %d, but the request was denied.",
4785: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4786: if (reason != NULL)
4787: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4788: return NULL;
1.99 markus 4789: }
1.372 markus 4790:
4791: memset(&cctx, 0, sizeof(cctx));
4792: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4793: &cctx, reason, errmsg);
4794: if (sock == -1) {
4795: channel_connect_ctx_free(&cctx);
4796: return NULL;
4797: }
4798:
4799: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4800: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4801: c->host_port = port;
4802: c->path = xstrdup(host);
4803: c->connect_ctx = cctx;
4804:
4805: return c;
1.336 millert 4806: }
4807:
4808: /* Check if connecting to that path is permitted and connect. */
4809: Channel *
1.367 djm 4810: channel_connect_to_path(struct ssh *ssh, const char *path,
4811: char *ctype, char *rname)
1.336 millert 4812: {
1.367 djm 4813: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4814: struct permission_set *pset = &sc->local_perms;
1.367 djm 4815: u_int i, permit, permit_adm = 1;
1.381 djm 4816: struct permission *perm;
1.336 millert 4817:
1.381 djm 4818: permit = pset->all_permitted;
1.336 millert 4819: if (!permit) {
1.381 djm 4820: for (i = 0; i < pset->num_permitted_user; i++) {
4821: perm = &pset->permitted_user[i];
4822: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4823: permit = 1;
4824: break;
4825: }
1.367 djm 4826: }
1.336 millert 4827: }
4828:
1.381 djm 4829: if (pset->num_permitted_admin > 0) {
1.336 millert 4830: permit_adm = 0;
1.381 djm 4831: for (i = 0; i < pset->num_permitted_admin; i++) {
4832: perm = &pset->permitted_admin[i];
4833: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4834: permit_adm = 1;
4835: break;
4836: }
1.367 djm 4837: }
1.336 millert 4838: }
4839:
4840: if (!permit || !permit_adm) {
4841: logit("Received request to connect to path %.100s, "
4842: "but the request was denied.", path);
4843: return NULL;
4844: }
1.367 djm 4845: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4846: }
4847:
4848: void
1.367 djm 4849: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4850: {
1.367 djm 4851: struct ssh_channels *sc = ssh->chanctxt;
4852: struct winsize ws;
4853: int r;
1.209 avsm 4854: u_int i;
1.204 djm 4855:
1.367 djm 4856: for (i = 0; i < sc->channels_alloc; i++) {
4857: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4858: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4859: continue;
1.393 deraadt 4860: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4861: continue;
1.367 djm 4862: channel_request_start(ssh, i, "window-change", 0);
4863: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4864: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4865: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4866: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4867: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4868: fatal_fr(r, "channel %u; send window-change", i);
1.204 djm 4869: }
1.372 markus 4870: }
4871:
4872: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4873: static Channel *
4874: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4875: {
4876: Channel *c;
4877: int r;
4878:
4879: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4880: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4881: c->host_port = 0;
4882: c->path = NULL;
4883:
4884: /*
4885: * We need to open the channel before we have a FD,
4886: * so that we can get SOCKS header from peer.
4887: */
4888: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4889: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4890: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4891: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 4892: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0)
4893: fatal_fr(r, "channel %i; confirm", c->self);
1.372 markus 4894: return c;
4895: }
4896:
4897: /* Return CONNECTING socket to remote host:port or local socket path */
4898: static int
4899: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4900: {
1.405 markus 4901: struct ssh_channels *sc = ssh->chanctxt;
4902: struct permission_set *pset = &sc->local_perms;
4903: struct permission *perm;
1.372 markus 4904: struct channel_connect cctx;
1.405 markus 4905: u_int i, permit_adm = 1;
1.372 markus 4906: int sock;
1.405 markus 4907:
4908: if (pset->num_permitted_admin > 0) {
4909: permit_adm = 0;
4910: for (i = 0; i < pset->num_permitted_admin; i++) {
4911: perm = &pset->permitted_admin[i];
4912: if (open_match(perm, c->path, c->host_port)) {
4913: permit_adm = 1;
4914: break;
4915: }
4916: }
4917: }
4918: if (!permit_adm) {
4919: debug_f("requested forward not permitted");
4920: return -1;
4921: }
1.372 markus 4922:
4923: memset(&cctx, 0, sizeof(cctx));
4924: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4925: NULL, &cctx, NULL, NULL);
4926: if (sock == -1)
4927: channel_connect_ctx_free(&cctx);
4928: else {
4929: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4930: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4931: c->connect_ctx = cctx;
4932: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4933: }
4934: return sock;
1.99 markus 4935: }
4936:
1.121 markus 4937: /* -- X11 forwarding */
1.1 deraadt 4938:
1.27 markus 4939: /*
4940: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4941: * Returns 0 and a suitable display number for the DISPLAY variable
4942: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4943: */
1.141 stevesk 4944: int
1.367 djm 4945: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4946: int x11_use_localhost, int single_connection,
4947: u_int *display_numberp, int **chanids)
1.1 deraadt 4948: {
1.149 markus 4949: Channel *nc = NULL;
1.31 markus 4950: int display_number, sock;
4951: u_short port;
1.35 markus 4952: struct addrinfo hints, *ai, *aitop;
4953: char strport[NI_MAXSERV];
4954: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4955:
1.224 markus 4956: if (chanids == NULL)
4957: return -1;
4958:
1.33 markus 4959: for (display_number = x11_display_offset;
1.148 deraadt 4960: display_number < MAX_DISPLAYS;
4961: display_number++) {
1.25 markus 4962: port = 6000 + display_number;
1.35 markus 4963: memset(&hints, 0, sizeof(hints));
1.367 djm 4964: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4965: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4966: hints.ai_socktype = SOCK_STREAM;
4967: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4968: if ((gaierr = getaddrinfo(NULL, strport,
4969: &hints, &aitop)) != 0) {
1.271 dtucker 4970: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4971: return -1;
1.25 markus 4972: }
1.35 markus 4973: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4974: if (ai->ai_family != AF_INET &&
4975: ai->ai_family != AF_INET6)
1.35 markus 4976: continue;
1.300 dtucker 4977: sock = socket(ai->ai_family, ai->ai_socktype,
4978: ai->ai_protocol);
1.393 deraadt 4979: if (sock == -1) {
1.35 markus 4980: error("socket: %.100s", strerror(errno));
1.203 markus 4981: freeaddrinfo(aitop);
1.141 stevesk 4982: return -1;
1.35 markus 4983: }
1.376 djm 4984: set_reuseaddr(sock);
1.393 deraadt 4985: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.403 djm 4986: debug2_f("bind port %d: %.100s", port,
4987: strerror(errno));
1.35 markus 4988: close(sock);
1.367 djm 4989: for (n = 0; n < num_socks; n++)
1.35 markus 4990: close(socks[n]);
4991: num_socks = 0;
4992: break;
4993: }
4994: socks[num_socks++] = sock;
4995: if (num_socks == NUM_SOCKS)
4996: break;
1.25 markus 4997: }
1.83 stevesk 4998: freeaddrinfo(aitop);
1.35 markus 4999: if (num_socks > 0)
5000: break;
1.25 markus 5001: }
5002: if (display_number >= MAX_DISPLAYS) {
5003: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 5004: return -1;
1.25 markus 5005: }
5006: /* Start listening for connections on the socket. */
1.35 markus 5007: for (n = 0; n < num_socks; n++) {
5008: sock = socks[n];
1.393 deraadt 5009: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 5010: error("listen: %.100s", strerror(errno));
5011: close(sock);
1.141 stevesk 5012: return -1;
1.35 markus 5013: }
1.25 markus 5014: }
1.35 markus 5015:
5016: /* Allocate a channel for each socket. */
1.242 djm 5017: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 5018: for (n = 0; n < num_socks; n++) {
5019: sock = socks[n];
1.424 djm 5020: nc = channel_new(ssh, "x11-listener",
1.51 markus 5021: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
5022: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 5023: 0, "X11 inet listener", 1);
1.167 markus 5024: nc->single_connection = single_connection;
1.224 markus 5025: (*chanids)[n] = nc->self;
1.35 markus 5026: }
1.224 markus 5027: (*chanids)[n] = -1;
1.1 deraadt 5028:
1.141 stevesk 5029: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 5030: *display_numberp = display_number;
1.367 djm 5031: return 0;
1.1 deraadt 5032: }
5033:
1.127 itojun 5034: static int
1.77 markus 5035: connect_local_xsocket(u_int dnr)
1.1 deraadt 5036: {
1.25 markus 5037: int sock;
5038: struct sockaddr_un addr;
5039:
1.147 stevesk 5040: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 deraadt 5041: if (sock == -1)
1.147 stevesk 5042: error("socket: %.100s", strerror(errno));
5043: memset(&addr, 0, sizeof(addr));
5044: addr.sun_family = AF_UNIX;
5045: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 5046: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 5047: return sock;
5048: close(sock);
1.25 markus 5049: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
5050: return -1;
1.1 deraadt 5051: }
5052:
1.51 markus 5053: int
1.367 djm 5054: x11_connect_display(struct ssh *ssh)
1.1 deraadt 5055: {
1.248 deraadt 5056: u_int display_number;
1.25 markus 5057: const char *display;
1.51 markus 5058: char buf[1024], *cp;
1.35 markus 5059: struct addrinfo hints, *ai, *aitop;
5060: char strport[NI_MAXSERV];
1.248 deraadt 5061: int gaierr, sock = 0;
1.25 markus 5062:
5063: /* Try to open a socket for the local X server. */
5064: display = getenv("DISPLAY");
5065: if (!display) {
5066: error("DISPLAY not set.");
1.51 markus 5067: return -1;
1.25 markus 5068: }
1.27 markus 5069: /*
5070: * Now we decode the value of the DISPLAY variable and make a
5071: * connection to the real X server.
5072: */
5073:
5074: /*
5075: * Check if it is a unix domain socket. Unix domain displays are in
5076: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
5077: */
1.25 markus 5078: if (strncmp(display, "unix:", 5) == 0 ||
5079: display[0] == ':') {
5080: /* Connect to the unix domain socket. */
1.367 djm 5081: if (sscanf(strrchr(display, ':') + 1, "%u",
5082: &display_number) != 1) {
5083: error("Could not parse display number from DISPLAY: "
5084: "%.100s", display);
1.51 markus 5085: return -1;
1.25 markus 5086: }
5087: /* Create a socket. */
5088: sock = connect_local_xsocket(display_number);
5089: if (sock < 0)
1.51 markus 5090: return -1;
1.25 markus 5091:
5092: /* OK, we now have a connection to the display. */
1.51 markus 5093: return sock;
1.25 markus 5094: }
1.27 markus 5095: /*
5096: * Connect to an inet socket. The DISPLAY value is supposedly
5097: * hostname:d[.s], where hostname may also be numeric IP address.
5098: */
1.145 stevesk 5099: strlcpy(buf, display, sizeof(buf));
1.25 markus 5100: cp = strchr(buf, ':');
5101: if (!cp) {
5102: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 5103: return -1;
1.25 markus 5104: }
5105: *cp = 0;
1.367 djm 5106: /*
5107: * buf now contains the host name. But first we parse the
5108: * display number.
5109: */
1.248 deraadt 5110: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 5111: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 5112: display);
1.51 markus 5113: return -1;
1.25 markus 5114: }
1.35 markus 5115:
5116: /* Look up the host address */
5117: memset(&hints, 0, sizeof(hints));
1.367 djm 5118: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 5119: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 5120: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 5121: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 5122: error("%.100s: unknown host. (%s)", buf,
5123: ssh_gai_strerror(gaierr));
1.51 markus 5124: return -1;
1.25 markus 5125: }
1.35 markus 5126: for (ai = aitop; ai; ai = ai->ai_next) {
5127: /* Create a socket. */
1.300 dtucker 5128: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 5129: if (sock == -1) {
1.194 markus 5130: debug2("socket: %.100s", strerror(errno));
1.41 markus 5131: continue;
5132: }
5133: /* Connect it to the display. */
1.393 deraadt 5134: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 5135: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 5136: 6000 + display_number, strerror(errno));
5137: close(sock);
5138: continue;
5139: }
5140: /* Success */
5141: break;
1.35 markus 5142: }
5143: freeaddrinfo(aitop);
5144: if (!ai) {
1.367 djm 5145: error("connect %.100s port %u: %.100s", buf,
5146: 6000 + display_number, strerror(errno));
1.51 markus 5147: return -1;
1.25 markus 5148: }
1.162 stevesk 5149: set_nodelay(sock);
1.51 markus 5150: return sock;
5151: }
5152:
5153: /*
1.27 markus 5154: * Requests forwarding of X11 connections, generates fake authentication
5155: * data, and enables authentication spoofing.
1.121 markus 5156: * This should be called in the client only.
1.27 markus 5157: */
1.49 markus 5158: void
1.367 djm 5159: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
5160: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 5161: {
1.367 djm 5162: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 5163: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 5164: u_int i, value;
1.367 djm 5165: const char *cp;
1.25 markus 5166: char *new_data;
1.367 djm 5167: int r, screen_number;
1.25 markus 5168:
1.367 djm 5169: if (sc->x11_saved_display == NULL)
5170: sc->x11_saved_display = xstrdup(disp);
5171: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 5172: error("x11_request_forwarding_with_spoofing: different "
5173: "$DISPLAY already forwarded");
5174: return;
5175: }
5176:
1.266 djm 5177: cp = strchr(disp, ':');
1.25 markus 5178: if (cp)
5179: cp = strchr(cp, '.');
5180: if (cp)
1.245 deraadt 5181: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 5182: else
5183: screen_number = 0;
5184:
1.367 djm 5185: if (sc->x11_saved_proto == NULL) {
1.219 djm 5186: /* Save protocol name. */
1.367 djm 5187: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 5188:
5189: /* Extract real authentication data. */
1.367 djm 5190: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 5191: for (i = 0; i < data_len; i++) {
1.403 djm 5192: if (sscanf(data + 2 * i, "%2x", &value) != 1) {
1.219 djm 5193: fatal("x11_request_forwarding: bad "
5194: "authentication data: %.100s", data);
1.403 djm 5195: }
1.367 djm 5196: sc->x11_saved_data[i] = value;
1.219 djm 5197: }
1.367 djm 5198: sc->x11_saved_data_len = data_len;
1.353 natano 5199:
5200: /* Generate fake data of the same length. */
1.367 djm 5201: sc->x11_fake_data = xmalloc(data_len);
5202: arc4random_buf(sc->x11_fake_data, data_len);
5203: sc->x11_fake_data_len = data_len;
1.25 markus 5204: }
5205:
5206: /* Convert the fake data into hex. */
1.367 djm 5207: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 5208:
5209: /* Send the request packet. */
1.367 djm 5210: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
5211: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
5212: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
5213: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
5214: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
5215: (r = sshpkt_send(ssh)) != 0 ||
5216: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 5217: fatal_fr(r, "send x11-req");
1.321 djm 5218: free(new_data);
1.1 deraadt 5219: }
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