Annotation of src/usr.bin/ssh/channels.c, Revision 1.435
1.435 ! djm 1: /* $OpenBSD: channels.c,v 1.434 2023/11/15 22:51:49 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: /* -- tcp forwarding */
89: /* special-case port number meaning allow any port */
90: #define FWD_PERMIT_ANY_PORT 0
1.1 deraadt 91:
1.367 djm 92: /* special-case wildcard meaning allow any host */
93: #define FWD_PERMIT_ANY_HOST "*"
1.1 deraadt 94:
1.367 djm 95: /* -- X11 forwarding */
96: /* Maximum number of fake X11 displays to try. */
97: #define MAX_DISPLAYS 1000
1.1 deraadt 98:
1.411 djm 99: /* Per-channel callback for pre/post IO actions */
1.410 djm 100: typedef void chan_fn(struct ssh *, Channel *c);
1.381 djm 101:
1.27 markus 102: /*
103: * Data structure for storing which hosts are permitted for forward requests.
104: * The local sides of any remote forwards are stored in this array to prevent
105: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
106: * network (which might be behind a firewall).
107: */
1.336 millert 108: /* XXX: streamlocal wants a path instead of host:port */
109: /* Overload host_to_connect; we could just make this match Forward */
110: /* XXX - can we use listen_host instead of listen_path? */
1.381 djm 111: struct permission {
1.41 markus 112: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 113: int port_to_connect; /* Connect to 'port'. */
1.333 markus 114: char *listen_host; /* Remote side should listen address. */
1.336 millert 115: char *listen_path; /* Remote side should listen path. */
116: int listen_port; /* Remote side should listen port. */
1.354 markus 117: Channel *downstream; /* Downstream mux*/
1.381 djm 118: };
119:
120: /*
121: * Stores the forwarding permission state for a single direction (local or
122: * remote).
123: */
124: struct permission_set {
125: /*
126: * List of all local permitted host/port pairs to allow for the
127: * user.
128: */
129: u_int num_permitted_user;
130: struct permission *permitted_user;
1.1 deraadt 131:
1.381 djm 132: /*
133: * List of all permitted host/port pairs to allow for the admin.
134: */
135: u_int num_permitted_admin;
136: struct permission *permitted_admin;
137:
138: /*
139: * If this is true, all opens/listens are permitted. This is the
140: * case on the server on which we have to trust the client anyway,
141: * and the user could do anything after logging in.
142: */
143: int all_permitted;
144: };
1.121 markus 145:
1.426 djm 146: /* Used to record timeouts per channel type */
147: struct ssh_channel_timeout {
148: char *type_pattern;
1.431 millert 149: int timeout_secs;
1.426 djm 150: };
151:
1.367 djm 152: /* Master structure for channels state */
153: struct ssh_channels {
154: /*
155: * Pointer to an array containing all allocated channels. The array
156: * is dynamically extended as needed.
157: */
158: Channel **channels;
1.257 dtucker 159:
1.367 djm 160: /*
161: * Size of the channel array. All slots of the array must always be
162: * initialized (at least the type field); unused slots set to NULL
163: */
164: u_int channels_alloc;
1.257 dtucker 165:
1.367 djm 166: /*
1.411 djm 167: * 'channel_pre*' are called just before IO to add any bits
168: * relevant to channels in the c->io_want bitmasks.
1.367 djm 169: *
170: * 'channel_post*': perform any appropriate operations for
1.411 djm 171: * channels which have c->io_ready events pending.
1.367 djm 172: */
173: chan_fn **channel_pre;
174: chan_fn **channel_post;
1.314 dtucker 175:
1.367 djm 176: /* -- tcp forwarding */
1.381 djm 177: struct permission_set local_perms;
178: struct permission_set remote_perms;
1.219 djm 179:
1.367 djm 180: /* -- X11 forwarding */
1.121 markus 181:
1.367 djm 182: /* Saved X11 local (client) display. */
183: char *x11_saved_display;
1.121 markus 184:
1.367 djm 185: /* Saved X11 authentication protocol name. */
186: char *x11_saved_proto;
1.347 djm 187:
1.367 djm 188: /* Saved X11 authentication data. This is the real data. */
189: char *x11_saved_data;
190: u_int x11_saved_data_len;
1.121 markus 191:
1.367 djm 192: /* Deadline after which all X11 connections are refused */
1.428 dtucker 193: time_t x11_refuse_time;
1.121 markus 194:
1.367 djm 195: /*
196: * Fake X11 authentication data. This is what the server will be
197: * sending us; we should replace any occurrences of this by the
198: * real data.
199: */
200: u_char *x11_fake_data;
201: u_int x11_fake_data_len;
1.121 markus 202:
1.367 djm 203: /* AF_UNSPEC or AF_INET or AF_INET6 */
204: int IPv4or6;
1.426 djm 205:
206: /* Channel timeouts by type */
207: struct ssh_channel_timeout *timeouts;
208: size_t ntimeouts;
1.367 djm 209: };
1.1 deraadt 210:
1.121 markus 211: /* helper */
1.367 djm 212: static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
1.354 markus 213: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 214:
1.276 djm 215: /* non-blocking connect helpers */
216: static int connect_next(struct channel_connect *);
217: static void channel_connect_ctx_free(struct channel_connect *);
1.372 markus 218: static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
219: static int rdynamic_connect_finish(struct ssh *, Channel *);
1.276 djm 220:
1.367 djm 221: /* Setup helper */
222: static void channel_handler_init(struct ssh_channels *sc);
223:
1.121 markus 224: /* -- channel core */
1.41 markus 225:
1.367 djm 226: void
227: channel_init_channels(struct ssh *ssh)
228: {
229: struct ssh_channels *sc;
230:
1.387 djm 231: if ((sc = calloc(1, sizeof(*sc))) == NULL)
1.403 djm 232: fatal_f("allocation failed");
1.367 djm 233: sc->channels_alloc = 10;
234: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
235: sc->IPv4or6 = AF_UNSPEC;
236: channel_handler_init(sc);
237:
238: ssh->chanctxt = sc;
239: }
240:
1.41 markus 241: Channel *
1.367 djm 242: channel_by_id(struct ssh *ssh, int id)
1.41 markus 243: {
244: Channel *c;
1.113 markus 245:
1.367 djm 246: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
1.403 djm 247: logit_f("%d: bad id", id);
1.41 markus 248: return NULL;
249: }
1.367 djm 250: c = ssh->chanctxt->channels[id];
1.113 markus 251: if (c == NULL) {
1.403 djm 252: logit_f("%d: bad id: channel free", id);
1.41 markus 253: return NULL;
254: }
255: return c;
1.55 markus 256: }
257:
1.354 markus 258: Channel *
1.368 djm 259: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 260: {
261: Channel *c;
262: u_int i;
263:
1.367 djm 264: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
265: c = ssh->chanctxt->channels[i];
1.368 djm 266: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 267: return c;
268: }
269: return NULL;
270: }
271:
1.27 markus 272: /*
1.229 markus 273: * Returns the channel if it is allowed to receive protocol messages.
274: * Private channels, like listening sockets, may not receive messages.
275: */
276: Channel *
1.367 djm 277: channel_lookup(struct ssh *ssh, int id)
1.229 markus 278: {
279: Channel *c;
280:
1.367 djm 281: if ((c = channel_by_id(ssh, id)) == NULL)
282: return NULL;
1.229 markus 283:
1.237 deraadt 284: switch (c->type) {
1.229 markus 285: case SSH_CHANNEL_X11_OPEN:
286: case SSH_CHANNEL_LARVAL:
287: case SSH_CHANNEL_CONNECTING:
288: case SSH_CHANNEL_DYNAMIC:
1.372 markus 289: case SSH_CHANNEL_RDYNAMIC_OPEN:
290: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 291: case SSH_CHANNEL_OPENING:
292: case SSH_CHANNEL_OPEN:
1.323 dtucker 293: case SSH_CHANNEL_ABANDONED:
1.354 markus 294: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 295: return c;
1.229 markus 296: }
297: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 298: return NULL;
1.229 markus 299: }
300:
301: /*
1.426 djm 302: * Add a timeout for open channels whose c->ctype (or c->xctype if it is set)
303: * match type_pattern.
304: */
305: void
306: channel_add_timeout(struct ssh *ssh, const char *type_pattern,
1.431 millert 307: int timeout_secs)
1.426 djm 308: {
309: struct ssh_channels *sc = ssh->chanctxt;
310:
1.431 millert 311: debug2_f("channel type \"%s\" timeout %d seconds",
1.426 djm 312: type_pattern, timeout_secs);
313: sc->timeouts = xrecallocarray(sc->timeouts, sc->ntimeouts,
314: sc->ntimeouts + 1, sizeof(*sc->timeouts));
315: sc->timeouts[sc->ntimeouts].type_pattern = xstrdup(type_pattern);
316: sc->timeouts[sc->ntimeouts].timeout_secs = timeout_secs;
317: sc->ntimeouts++;
318: }
319:
320: /* Clears all previously-added channel timeouts */
321: void
322: channel_clear_timeouts(struct ssh *ssh)
323: {
324: struct ssh_channels *sc = ssh->chanctxt;
325: size_t i;
326:
327: debug3_f("clearing");
328: for (i = 0; i < sc->ntimeouts; i++)
329: free(sc->timeouts[i].type_pattern);
330: free(sc->timeouts);
331: sc->timeouts = NULL;
332: sc->ntimeouts = 0;
333: }
334:
1.431 millert 335: static int
1.426 djm 336: lookup_timeout(struct ssh *ssh, const char *type)
337: {
338: struct ssh_channels *sc = ssh->chanctxt;
339: size_t i;
340:
341: for (i = 0; i < sc->ntimeouts; i++) {
342: if (match_pattern(type, sc->timeouts[i].type_pattern))
343: return sc->timeouts[i].timeout_secs;
344: }
345:
346: return 0;
347: }
348:
349: /*
1.425 djm 350: * Sets "extended type" of a channel; used by session layer to add additional
351: * information about channel types (e.g. shell, login, subsystem) that can then
352: * be used to select timeouts.
1.426 djm 353: * Will reset c->inactive_deadline as a side-effect.
1.425 djm 354: */
355: void
356: channel_set_xtype(struct ssh *ssh, int id, const char *xctype)
357: {
358: Channel *c;
359:
360: if ((c = channel_by_id(ssh, id)) == NULL)
361: fatal_f("missing channel %d", id);
362: if (c->xctype != NULL)
363: free(c->xctype);
364: c->xctype = xstrdup(xctype);
1.426 djm 365: /* Type has changed, so look up inactivity deadline again */
366: c->inactive_deadline = lookup_timeout(ssh, c->xctype);
367: debug2_f("labeled channel %d as %s (inactive timeout %u)", id, xctype,
368: c->inactive_deadline);
1.425 djm 369: }
370:
371: /*
1.55 markus 372: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 373: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 374: */
1.127 itojun 375: static void
1.367 djm 376: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 377: int extusage, int nonblock, int is_tty)
1.1 deraadt 378: {
1.418 markus 379: int val;
380:
1.298 dtucker 381: if (rfd != -1)
1.430 dtucker 382: (void)fcntl(rfd, F_SETFD, FD_CLOEXEC);
1.298 dtucker 383: if (wfd != -1 && wfd != rfd)
1.430 dtucker 384: (void)fcntl(wfd, F_SETFD, FD_CLOEXEC);
1.298 dtucker 385: if (efd != -1 && efd != rfd && efd != wfd)
1.430 dtucker 386: (void)fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 387:
1.52 markus 388: c->rfd = rfd;
389: c->wfd = wfd;
390: c->sock = (rfd == wfd) ? rfd : -1;
391: c->efd = efd;
392: c->extended_usage = extusage;
1.71 markus 393:
1.282 dtucker 394: if ((c->isatty = is_tty) != 0)
1.194 markus 395: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 396:
1.71 markus 397: /* enable nonblocking mode */
1.407 djm 398: c->restore_block = 0;
399: if (nonblock == CHANNEL_NONBLOCK_STDIO) {
400: /*
401: * Special handling for stdio file descriptors: do not set
402: * non-blocking mode if they are TTYs. Otherwise prepare to
403: * restore their blocking state on exit to avoid interfering
404: * with other programs that follow.
405: */
1.418 markus 406: if (rfd != -1 && !isatty(rfd) &&
407: (val = fcntl(rfd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) {
1.427 djm 408: c->restore_flags[0] = val;
1.407 djm 409: c->restore_block |= CHANNEL_RESTORE_RFD;
410: set_nonblock(rfd);
411: }
1.418 markus 412: if (wfd != -1 && !isatty(wfd) &&
413: (val = fcntl(wfd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) {
1.427 djm 414: c->restore_flags[1] = val;
1.407 djm 415: c->restore_block |= CHANNEL_RESTORE_WFD;
416: set_nonblock(wfd);
417: }
1.418 markus 418: if (efd != -1 && !isatty(efd) &&
419: (val = fcntl(efd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) {
1.427 djm 420: c->restore_flags[2] = val;
1.407 djm 421: c->restore_block |= CHANNEL_RESTORE_EFD;
422: set_nonblock(efd);
423: }
424: } else if (nonblock) {
1.71 markus 425: if (rfd != -1)
426: set_nonblock(rfd);
427: if (wfd != -1)
428: set_nonblock(wfd);
429: if (efd != -1)
430: set_nonblock(efd);
431: }
1.52 markus 432: }
433:
434: /*
1.419 djm 435: * Allocate a new channel object and set its type and socket.
1.52 markus 436: */
1.113 markus 437: Channel *
1.367 djm 438: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.419 djm 439: u_int window, u_int maxpack, int extusage, const char *remote_name,
440: int nonblock)
1.52 markus 441: {
1.367 djm 442: struct ssh_channels *sc = ssh->chanctxt;
443: u_int i, found;
1.52 markus 444: Channel *c;
1.402 djm 445: int r;
1.25 markus 446:
447: /* Try to find a free slot where to put the new channel. */
1.367 djm 448: for (i = 0; i < sc->channels_alloc; i++) {
449: if (sc->channels[i] == NULL) {
1.25 markus 450: /* Found a free slot. */
1.367 djm 451: found = i;
1.25 markus 452: break;
453: }
1.367 djm 454: }
455: if (i >= sc->channels_alloc) {
456: /*
457: * There are no free slots. Take last+1 slot and expand
458: * the array.
459: */
460: found = sc->channels_alloc;
461: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
1.403 djm 462: fatal_f("internal error: channels_alloc %d too big",
463: sc->channels_alloc);
1.367 djm 464: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
465: sc->channels_alloc + 10, sizeof(*sc->channels));
466: sc->channels_alloc += 10;
467: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 468: }
1.113 markus 469: /* Initialize and return new channel. */
1.367 djm 470: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
471: if ((c->input = sshbuf_new()) == NULL ||
472: (c->output = sshbuf_new()) == NULL ||
473: (c->extended = sshbuf_new()) == NULL)
1.403 djm 474: fatal_f("sshbuf_new failed");
1.402 djm 475: if ((r = sshbuf_set_max_size(c->input, CHAN_INPUT_MAX)) != 0)
1.403 djm 476: fatal_fr(r, "sshbuf_set_max_size");
1.159 markus 477: c->ostate = CHAN_OUTPUT_OPEN;
478: c->istate = CHAN_INPUT_OPEN;
1.367 djm 479: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 480: c->self = found;
481: c->type = type;
1.41 markus 482: c->ctype = ctype;
1.51 markus 483: c->local_window = window;
484: c->local_window_max = window;
485: c->local_maxpacket = maxpack;
1.190 markus 486: c->remote_name = xstrdup(remote_name);
1.302 djm 487: c->ctl_chan = -1;
1.299 markus 488: c->delayed = 1; /* prevent call to channel_post handler */
1.426 djm 489: c->inactive_deadline = lookup_timeout(ssh, c->ctype);
1.275 djm 490: TAILQ_INIT(&c->status_confirms);
1.426 djm 491: debug("channel %d: new %s [%s] (inactive timeout: %u)",
492: found, c->ctype, remote_name, c->inactive_deadline);
1.113 markus 493: return c;
1.1 deraadt 494: }
1.52 markus 495:
1.132 markus 496: int
1.407 djm 497: channel_close_fd(struct ssh *ssh, Channel *c, int *fdp)
1.132 markus 498: {
1.407 djm 499: int ret, fd = *fdp;
1.132 markus 500:
1.407 djm 501: if (fd == -1)
502: return 0;
503:
1.427 djm 504: /* restore blocking */
505: if (*fdp == c->rfd &&
506: (c->restore_block & CHANNEL_RESTORE_RFD) != 0)
507: (void)fcntl(*fdp, F_SETFL, c->restore_flags[0]);
508: else if (*fdp == c->wfd &&
509: (c->restore_block & CHANNEL_RESTORE_WFD) != 0)
510: (void)fcntl(*fdp, F_SETFL, c->restore_flags[1]);
511: else if (*fdp == c->efd &&
512: (c->restore_block & CHANNEL_RESTORE_EFD) != 0)
513: (void)fcntl(*fdp, F_SETFL, c->restore_flags[2]);
1.407 djm 514:
1.411 djm 515: if (*fdp == c->rfd) {
516: c->io_want &= ~SSH_CHAN_IO_RFD;
517: c->io_ready &= ~SSH_CHAN_IO_RFD;
518: c->rfd = -1;
1.415 djm 519: c->pfds[0] = -1;
1.411 djm 520: }
521: if (*fdp == c->wfd) {
522: c->io_want &= ~SSH_CHAN_IO_WFD;
523: c->io_ready &= ~SSH_CHAN_IO_WFD;
524: c->wfd = -1;
1.415 djm 525: c->pfds[1] = -1;
1.411 djm 526: }
527: if (*fdp == c->efd) {
528: c->io_want &= ~SSH_CHAN_IO_EFD;
529: c->io_ready &= ~SSH_CHAN_IO_EFD;
530: c->efd = -1;
1.415 djm 531: c->pfds[2] = -1;
1.411 djm 532: }
533: if (*fdp == c->sock) {
534: c->io_want &= ~SSH_CHAN_IO_SOCK;
535: c->io_ready &= ~SSH_CHAN_IO_SOCK;
536: c->sock = -1;
1.415 djm 537: c->pfds[3] = -1;
1.411 djm 538: }
539:
1.407 djm 540: ret = close(fd);
1.411 djm 541: *fdp = -1; /* probably redundant */
1.132 markus 542: return ret;
543: }
544:
1.52 markus 545: /* Close all channel fd/socket. */
1.127 itojun 546: static void
1.367 djm 547: channel_close_fds(struct ssh *ssh, Channel *c)
548: {
1.379 tb 549: int sock = c->sock, rfd = c->rfd, wfd = c->wfd, efd = c->efd;
550:
1.407 djm 551: channel_close_fd(ssh, c, &c->sock);
1.379 tb 552: if (rfd != sock)
1.407 djm 553: channel_close_fd(ssh, c, &c->rfd);
1.379 tb 554: if (wfd != sock && wfd != rfd)
1.407 djm 555: channel_close_fd(ssh, c, &c->wfd);
1.379 tb 556: if (efd != sock && efd != rfd && efd != wfd)
1.407 djm 557: channel_close_fd(ssh, c, &c->efd);
1.367 djm 558: }
559:
560: static void
1.381 djm 561: fwd_perm_clear(struct permission *perm)
1.52 markus 562: {
1.381 djm 563: free(perm->host_to_connect);
564: free(perm->listen_host);
565: free(perm->listen_path);
1.398 dtucker 566: memset(perm, 0, sizeof(*perm));
1.367 djm 567: }
568:
1.381 djm 569: /* Returns an printable name for the specified forwarding permission list */
570: static const char *
571: fwd_ident(int who, int where)
572: {
573: if (who == FORWARD_ADM) {
574: if (where == FORWARD_LOCAL)
575: return "admin local";
576: else if (where == FORWARD_REMOTE)
577: return "admin remote";
578: } else if (who == FORWARD_USER) {
579: if (where == FORWARD_LOCAL)
580: return "user local";
581: else if (where == FORWARD_REMOTE)
582: return "user remote";
583: }
584: fatal("Unknown forward permission list %d/%d", who, where);
585: }
586:
587: /* Returns the forwarding permission list for the specified direction */
588: static struct permission_set *
589: permission_set_get(struct ssh *ssh, int where)
590: {
591: struct ssh_channels *sc = ssh->chanctxt;
1.367 djm 592:
1.381 djm 593: switch (where) {
594: case FORWARD_LOCAL:
595: return &sc->local_perms;
596: break;
597: case FORWARD_REMOTE:
598: return &sc->remote_perms;
599: break;
600: default:
1.403 djm 601: fatal_f("invalid forwarding direction %d", where);
1.381 djm 602: }
603: }
604:
1.392 dtucker 605: /* Returns pointers to the specified forwarding list and its element count */
1.381 djm 606: static void
607: permission_set_get_array(struct ssh *ssh, int who, int where,
608: struct permission ***permpp, u_int **npermpp)
609: {
610: struct permission_set *pset = permission_set_get(ssh, where);
611:
612: switch (who) {
613: case FORWARD_USER:
614: *permpp = &pset->permitted_user;
615: *npermpp = &pset->num_permitted_user;
616: break;
617: case FORWARD_ADM:
618: *permpp = &pset->permitted_admin;
619: *npermpp = &pset->num_permitted_admin;
620: break;
621: default:
1.403 djm 622: fatal_f("invalid forwarding client %d", who);
1.381 djm 623: }
624: }
625:
1.409 jsg 626: /* Adds an entry to the specified forwarding list */
1.367 djm 627: static int
1.381 djm 628: permission_set_add(struct ssh *ssh, int who, int where,
1.367 djm 629: const char *host_to_connect, int port_to_connect,
630: const char *listen_host, const char *listen_path, int listen_port,
631: Channel *downstream)
632: {
1.381 djm 633: struct permission **permp;
634: u_int n, *npermp;
1.367 djm 635:
1.381 djm 636: permission_set_get_array(ssh, who, where, &permp, &npermp);
1.367 djm 637:
1.381 djm 638: if (*npermp >= INT_MAX)
1.403 djm 639: fatal_f("%s overflow", fwd_ident(who, where));
1.367 djm 640:
1.381 djm 641: *permp = xrecallocarray(*permp, *npermp, *npermp + 1, sizeof(**permp));
642: n = (*npermp)++;
1.367 djm 643: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
1.381 djm 644: (*permp)[n].host_to_connect = MAYBE_DUP(host_to_connect);
645: (*permp)[n].port_to_connect = port_to_connect;
646: (*permp)[n].listen_host = MAYBE_DUP(listen_host);
647: (*permp)[n].listen_path = MAYBE_DUP(listen_path);
648: (*permp)[n].listen_port = listen_port;
649: (*permp)[n].downstream = downstream;
1.367 djm 650: #undef MAYBE_DUP
651: return (int)n;
652: }
653:
654: static void
655: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
656: {
657: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 658: struct permission_set *pset = &sc->local_perms;
659: struct permission *perm;
1.367 djm 660: int r;
661: u_int i;
662:
1.381 djm 663: for (i = 0; i < pset->num_permitted_user; i++) {
664: perm = &pset->permitted_user[i];
665: if (perm->downstream != c)
1.367 djm 666: continue;
667:
668: /* cancel on the server, since mux client is gone */
669: debug("channel %d: cleanup remote forward for %s:%u",
1.381 djm 670: c->self, perm->listen_host, perm->listen_port);
1.367 djm 671: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
672: (r = sshpkt_put_cstring(ssh,
673: "cancel-tcpip-forward")) != 0 ||
674: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
675: (r = sshpkt_put_cstring(ssh,
1.381 djm 676: channel_rfwd_bind_host(perm->listen_host))) != 0 ||
677: (r = sshpkt_put_u32(ssh, perm->listen_port)) != 0 ||
1.367 djm 678: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 679: fatal_fr(r, "channel %i", c->self);
1.367 djm 680: }
1.381 djm 681: fwd_perm_clear(perm); /* unregister */
1.367 djm 682: }
1.121 markus 683: }
684:
685: /* Free the channel and close its fd/socket. */
686: void
1.367 djm 687: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 688: {
1.367 djm 689: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 690: char *s;
1.209 avsm 691: u_int i, n;
1.354 markus 692: Channel *other;
1.275 djm 693: struct channel_confirm *cc;
1.121 markus 694:
1.367 djm 695: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
696: if ((other = sc->channels[i]) == NULL)
697: continue;
698: n++;
699: /* detach from mux client and prepare for closing */
700: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
701: other->type == SSH_CHANNEL_MUX_PROXY &&
702: other->mux_ctx == c) {
703: other->mux_ctx = NULL;
704: other->type = SSH_CHANNEL_OPEN;
705: other->istate = CHAN_INPUT_CLOSED;
706: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 707: }
708: }
1.209 avsm 709: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 710: c->remote_name ? c->remote_name : "???", n);
711:
1.408 mbuhl 712: if (c->type == SSH_CHANNEL_MUX_CLIENT) {
1.367 djm 713: mux_remove_remote_forwardings(ssh, c);
1.408 mbuhl 714: free(c->mux_ctx);
715: c->mux_ctx = NULL;
716: } else if (c->type == SSH_CHANNEL_MUX_LISTENER) {
1.401 djm 717: free(c->mux_ctx);
718: c->mux_ctx = NULL;
719: }
1.354 markus 720:
1.384 markus 721: if (log_level_get() >= SYSLOG_LEVEL_DEBUG3) {
722: s = channel_open_message(ssh);
723: debug3("channel %d: status: %s", c->self, s);
724: free(s);
725: }
1.121 markus 726:
1.367 djm 727: channel_close_fds(ssh, c);
728: sshbuf_free(c->input);
729: sshbuf_free(c->output);
730: sshbuf_free(c->extended);
731: c->input = c->output = c->extended = NULL;
1.321 djm 732: free(c->remote_name);
733: c->remote_name = NULL;
734: free(c->path);
735: c->path = NULL;
736: free(c->listening_addr);
737: c->listening_addr = NULL;
1.425 djm 738: free(c->xctype);
739: c->xctype = NULL;
1.275 djm 740: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
741: if (cc->abandon_cb != NULL)
1.367 djm 742: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 743: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 744: freezero(cc, sizeof(*cc));
1.275 djm 745: }
1.280 djm 746: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 747: c->filter_cleanup(ssh, c->self, c->filter_ctx);
748: sc->channels[c->self] = NULL;
1.396 jsg 749: freezero(c, sizeof(*c));
1.121 markus 750: }
751:
752: void
1.367 djm 753: channel_free_all(struct ssh *ssh)
1.121 markus 754: {
1.209 avsm 755: u_int i;
1.390 dtucker 756: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 757:
1.390 dtucker 758: for (i = 0; i < sc->channels_alloc; i++)
759: if (sc->channels[i] != NULL)
760: channel_free(ssh, sc->channels[i]);
761:
762: free(sc->channels);
763: sc->channels = NULL;
764: sc->channels_alloc = 0;
765:
766: free(sc->x11_saved_display);
767: sc->x11_saved_display = NULL;
768:
769: free(sc->x11_saved_proto);
770: sc->x11_saved_proto = NULL;
771:
772: free(sc->x11_saved_data);
773: sc->x11_saved_data = NULL;
774: sc->x11_saved_data_len = 0;
775:
776: free(sc->x11_fake_data);
777: sc->x11_fake_data = NULL;
778: sc->x11_fake_data_len = 0;
1.131 markus 779: }
780:
1.121 markus 781: /*
782: * Closes the sockets/fds of all channels. This is used to close extra file
783: * descriptors after a fork.
784: */
785: void
1.367 djm 786: channel_close_all(struct ssh *ssh)
1.121 markus 787: {
1.209 avsm 788: u_int i;
1.121 markus 789:
1.367 djm 790: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
791: if (ssh->chanctxt->channels[i] != NULL)
792: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 793: }
794:
795: /*
1.131 markus 796: * Stop listening to channels.
797: */
798: void
1.367 djm 799: channel_stop_listening(struct ssh *ssh)
1.131 markus 800: {
1.209 avsm 801: u_int i;
1.131 markus 802: Channel *c;
803:
1.367 djm 804: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
805: c = ssh->chanctxt->channels[i];
1.131 markus 806: if (c != NULL) {
807: switch (c->type) {
808: case SSH_CHANNEL_AUTH_SOCKET:
809: case SSH_CHANNEL_PORT_LISTENER:
810: case SSH_CHANNEL_RPORT_LISTENER:
811: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 812: case SSH_CHANNEL_UNIX_LISTENER:
813: case SSH_CHANNEL_RUNIX_LISTENER:
1.407 djm 814: channel_close_fd(ssh, c, &c->sock);
1.367 djm 815: channel_free(ssh, c);
1.131 markus 816: break;
817: }
818: }
819: }
820: }
821:
822: /*
1.121 markus 823: * Returns true if no channel has too much buffered data, and false if one or
824: * more channel is overfull.
825: */
826: int
1.367 djm 827: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 828: {
829: u_int i;
1.367 djm 830: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 831: Channel *c;
832:
1.367 djm 833: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
834: c = ssh->chanctxt->channels[i];
835: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
836: continue;
837: if (sshbuf_len(c->output) > maxsize) {
838: debug2("channel %d: big output buffer %zu > %u",
839: c->self, sshbuf_len(c->output), maxsize);
840: return 0;
1.121 markus 841: }
842: }
843: return 1;
844: }
845:
846: /* Returns true if any channel is still open. */
847: int
1.367 djm 848: channel_still_open(struct ssh *ssh)
1.121 markus 849: {
1.209 avsm 850: u_int i;
1.121 markus 851: Channel *c;
852:
1.367 djm 853: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
854: c = ssh->chanctxt->channels[i];
1.121 markus 855: if (c == NULL)
856: continue;
857: switch (c->type) {
858: case SSH_CHANNEL_X11_LISTENER:
859: case SSH_CHANNEL_PORT_LISTENER:
860: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 861: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 862: case SSH_CHANNEL_CLOSED:
863: case SSH_CHANNEL_AUTH_SOCKET:
864: case SSH_CHANNEL_DYNAMIC:
1.372 markus 865: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 866: case SSH_CHANNEL_CONNECTING:
867: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 868: case SSH_CHANNEL_ABANDONED:
1.336 millert 869: case SSH_CHANNEL_UNIX_LISTENER:
870: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 871: continue;
872: case SSH_CHANNEL_LARVAL:
873: continue;
874: case SSH_CHANNEL_OPENING:
875: case SSH_CHANNEL_OPEN:
1.372 markus 876: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 877: case SSH_CHANNEL_X11_OPEN:
1.302 djm 878: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 879: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 880: return 1;
881: default:
1.403 djm 882: fatal_f("bad channel type %d", c->type);
1.121 markus 883: /* NOTREACHED */
884: }
1.434 djm 885: }
886: return 0;
887: }
888:
889: /* Returns true if a channel with a TTY is open. */
890: int
891: channel_tty_open(struct ssh *ssh)
892: {
893: u_int i;
894: Channel *c;
895:
896: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
897: c = ssh->chanctxt->channels[i];
898: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
899: continue;
900: if (c->client_tty)
901: return 1;
1.121 markus 902: }
903: return 0;
904: }
905:
906: /* Returns the id of an open channel suitable for keepaliving */
907: int
1.367 djm 908: channel_find_open(struct ssh *ssh)
1.121 markus 909: {
1.209 avsm 910: u_int i;
1.121 markus 911: Channel *c;
912:
1.367 djm 913: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
914: c = ssh->chanctxt->channels[i];
1.368 djm 915: if (c == NULL || !c->have_remote_id)
1.121 markus 916: continue;
917: switch (c->type) {
918: case SSH_CHANNEL_CLOSED:
919: case SSH_CHANNEL_DYNAMIC:
1.372 markus 920: case SSH_CHANNEL_RDYNAMIC_OPEN:
921: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 922: case SSH_CHANNEL_X11_LISTENER:
923: case SSH_CHANNEL_PORT_LISTENER:
924: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 925: case SSH_CHANNEL_MUX_LISTENER:
926: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 927: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 928: case SSH_CHANNEL_OPENING:
929: case SSH_CHANNEL_CONNECTING:
930: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 931: case SSH_CHANNEL_ABANDONED:
1.336 millert 932: case SSH_CHANNEL_UNIX_LISTENER:
933: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 934: continue;
935: case SSH_CHANNEL_LARVAL:
936: case SSH_CHANNEL_AUTH_SOCKET:
937: case SSH_CHANNEL_OPEN:
938: case SSH_CHANNEL_X11_OPEN:
939: return i;
940: default:
1.403 djm 941: fatal_f("bad channel type %d", c->type);
1.121 markus 942: /* NOTREACHED */
943: }
944: }
945: return -1;
946: }
947:
1.385 djm 948: /* Returns the state of the channel's extended usage flag */
949: const char *
950: channel_format_extended_usage(const Channel *c)
951: {
952: if (c->efd == -1)
953: return "closed";
954:
955: switch (c->extended_usage) {
956: case CHAN_EXTENDED_WRITE:
957: return "write";
958: case CHAN_EXTENDED_READ:
959: return "read";
960: case CHAN_EXTENDED_IGNORE:
961: return "ignore";
962: default:
963: return "UNKNOWN";
964: }
965: }
966:
1.386 djm 967: static char *
968: channel_format_status(const Channel *c)
969: {
970: char *ret = NULL;
971:
1.425 djm 972: xasprintf(&ret, "t%d [%s] %s%u i%u/%zu o%u/%zu e[%s]/%zu "
1.411 djm 973: "fd %d/%d/%d sock %d cc %d io 0x%02x/0x%02x",
1.425 djm 974: c->type, c->xctype != NULL ? c->xctype : c->ctype,
1.386 djm 975: c->have_remote_id ? "r" : "nr", c->remote_id,
976: c->istate, sshbuf_len(c->input),
977: c->ostate, sshbuf_len(c->output),
978: channel_format_extended_usage(c), sshbuf_len(c->extended),
1.411 djm 979: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan,
980: c->io_want, c->io_ready);
1.386 djm 981: return ret;
982: }
983:
1.121 markus 984: /*
985: * Returns a message describing the currently open forwarded connections,
986: * suitable for sending to the client. The message contains crlf pairs for
987: * newlines.
988: */
989: char *
1.367 djm 990: channel_open_message(struct ssh *ssh)
1.121 markus 991: {
1.367 djm 992: struct sshbuf *buf;
1.121 markus 993: Channel *c;
1.209 avsm 994: u_int i;
1.367 djm 995: int r;
1.386 djm 996: char *cp, *ret;
1.121 markus 997:
1.367 djm 998: if ((buf = sshbuf_new()) == NULL)
1.403 djm 999: fatal_f("sshbuf_new");
1.367 djm 1000: if ((r = sshbuf_putf(buf,
1001: "The following connections are open:\r\n")) != 0)
1.403 djm 1002: fatal_fr(r, "sshbuf_putf");
1.367 djm 1003: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
1004: c = ssh->chanctxt->channels[i];
1.121 markus 1005: if (c == NULL)
1006: continue;
1007: switch (c->type) {
1008: case SSH_CHANNEL_X11_LISTENER:
1009: case SSH_CHANNEL_PORT_LISTENER:
1010: case SSH_CHANNEL_RPORT_LISTENER:
1011: case SSH_CHANNEL_CLOSED:
1012: case SSH_CHANNEL_AUTH_SOCKET:
1013: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 1014: case SSH_CHANNEL_ABANDONED:
1.302 djm 1015: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 1016: case SSH_CHANNEL_UNIX_LISTENER:
1017: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 1018: continue;
1019: case SSH_CHANNEL_LARVAL:
1020: case SSH_CHANNEL_OPENING:
1021: case SSH_CHANNEL_CONNECTING:
1022: case SSH_CHANNEL_DYNAMIC:
1.372 markus 1023: case SSH_CHANNEL_RDYNAMIC_OPEN:
1024: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 1025: case SSH_CHANNEL_OPEN:
1026: case SSH_CHANNEL_X11_OPEN:
1.354 markus 1027: case SSH_CHANNEL_MUX_PROXY:
1028: case SSH_CHANNEL_MUX_CLIENT:
1.386 djm 1029: cp = channel_format_status(c);
1030: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
1031: c->self, c->remote_name, cp)) != 0) {
1032: free(cp);
1.403 djm 1033: fatal_fr(r, "sshbuf_putf");
1.386 djm 1034: }
1035: free(cp);
1.121 markus 1036: continue;
1037: default:
1.403 djm 1038: fatal_f("bad channel type %d", c->type);
1.121 markus 1039: /* NOTREACHED */
1040: }
1041: }
1.367 djm 1042: if ((ret = sshbuf_dup_string(buf)) == NULL)
1.403 djm 1043: fatal_f("sshbuf_dup_string");
1.367 djm 1044: sshbuf_free(buf);
1045: return ret;
1046: }
1047:
1048: static void
1049: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
1050: {
1051: int r;
1052:
1053: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
1054: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
1055: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1056: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1057: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
1.403 djm 1058: fatal_r(r, "%s: channel %i: open", where, c->self);
1.367 djm 1059: }
1.121 markus 1060: }
1061:
1062: void
1.367 djm 1063: channel_send_open(struct ssh *ssh, int id)
1.121 markus 1064: {
1.367 djm 1065: Channel *c = channel_lookup(ssh, id);
1066: int r;
1.180 deraadt 1067:
1.121 markus 1068: if (c == NULL) {
1.188 itojun 1069: logit("channel_send_open: %d: bad id", id);
1.121 markus 1070: return;
1071: }
1.184 markus 1072: debug2("channel %d: send open", id);
1.367 djm 1073: open_preamble(ssh, __func__, c, c->ctype);
1074: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1075: fatal_fr(r, "channel %i", c->self);
1.121 markus 1076: }
1077:
1078: void
1.367 djm 1079: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 1080: {
1.367 djm 1081: Channel *c = channel_lookup(ssh, id);
1082: int r;
1.180 deraadt 1083:
1.121 markus 1084: if (c == NULL) {
1.403 djm 1085: logit_f("%d: unknown channel id", id);
1.121 markus 1086: return;
1087: }
1.368 djm 1088: if (!c->have_remote_id)
1.403 djm 1089: fatal_f("channel %d: no remote id", c->self);
1.368 djm 1090:
1.204 djm 1091: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 1092: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
1093: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1094: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
1095: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
1.403 djm 1096: fatal_fr(r, "channel %i", c->self);
1.367 djm 1097: }
1.121 markus 1098: }
1.241 deraadt 1099:
1.121 markus 1100: void
1.367 djm 1101: channel_register_status_confirm(struct ssh *ssh, int id,
1102: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 1103: {
1104: struct channel_confirm *cc;
1105: Channel *c;
1106:
1.367 djm 1107: if ((c = channel_lookup(ssh, id)) == NULL)
1.403 djm 1108: fatal_f("%d: bad id", id);
1.275 djm 1109:
1.327 djm 1110: cc = xcalloc(1, sizeof(*cc));
1.275 djm 1111: cc->cb = cb;
1112: cc->abandon_cb = abandon_cb;
1113: cc->ctx = ctx;
1114: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
1115: }
1116:
1117: void
1.367 djm 1118: channel_register_open_confirm(struct ssh *ssh, int id,
1119: channel_open_fn *fn, void *ctx)
1.121 markus 1120: {
1.367 djm 1121: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1122:
1.121 markus 1123: if (c == NULL) {
1.403 djm 1124: logit_f("%d: bad id", id);
1.121 markus 1125: return;
1126: }
1.275 djm 1127: c->open_confirm = fn;
1128: c->open_confirm_ctx = ctx;
1.121 markus 1129: }
1.241 deraadt 1130:
1.121 markus 1131: void
1.367 djm 1132: channel_register_cleanup(struct ssh *ssh, int id,
1133: channel_callback_fn *fn, int do_close)
1.121 markus 1134: {
1.367 djm 1135: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1136:
1.121 markus 1137: if (c == NULL) {
1.403 djm 1138: logit_f("%d: bad id", id);
1.121 markus 1139: return;
1140: }
1.131 markus 1141: c->detach_user = fn;
1.225 djm 1142: c->detach_close = do_close;
1.121 markus 1143: }
1.241 deraadt 1144:
1.121 markus 1145: void
1.367 djm 1146: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 1147: {
1.367 djm 1148: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1149:
1.121 markus 1150: if (c == NULL) {
1.403 djm 1151: logit_f("%d: bad id", id);
1.121 markus 1152: return;
1.52 markus 1153: }
1.131 markus 1154: c->detach_user = NULL;
1.225 djm 1155: c->detach_close = 0;
1.121 markus 1156: }
1.241 deraadt 1157:
1.121 markus 1158: void
1.367 djm 1159: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1160: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1161: {
1.367 djm 1162: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1163:
1.121 markus 1164: if (c == NULL) {
1.403 djm 1165: logit_f("%d: bad id", id);
1.121 markus 1166: return;
1.52 markus 1167: }
1.231 reyk 1168: c->input_filter = ifn;
1169: c->output_filter = ofn;
1.279 djm 1170: c->filter_ctx = ctx;
1.280 djm 1171: c->filter_cleanup = cfn;
1.52 markus 1172: }
1173:
1.49 markus 1174: void
1.367 djm 1175: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1176: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1177: {
1.367 djm 1178: Channel *c = channel_lookup(ssh, id);
1179: int r;
1.180 deraadt 1180:
1.121 markus 1181: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1182: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1183: if (!c->have_remote_id)
1.403 djm 1184: fatal_f("channel %d: no remote id", c->self);
1.368 djm 1185:
1.367 djm 1186: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1187: c->type = SSH_CHANNEL_OPEN;
1.426 djm 1188: c->lastused = monotime();
1.168 markus 1189: c->local_window = c->local_window_max = window_max;
1.367 djm 1190:
1191: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1192: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1193: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1194: (r = sshpkt_send(ssh)) != 0)
1.403 djm 1195: fatal_fr(r, "channel %i", c->self);
1.1 deraadt 1196: }
1197:
1.127 itojun 1198: static void
1.410 djm 1199: channel_pre_listener(struct ssh *ssh, Channel *c)
1.41 markus 1200: {
1.410 djm 1201: c->io_want = SSH_CHAN_IO_SOCK_R;
1.41 markus 1202: }
1203:
1.127 itojun 1204: static void
1.410 djm 1205: channel_pre_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1206: {
1207: debug3("channel %d: waiting for connection", c->self);
1.410 djm 1208: c->io_want = SSH_CHAN_IO_SOCK_W;
1.75 markus 1209: }
1210:
1.127 itojun 1211: static void
1.410 djm 1212: channel_pre_open(struct ssh *ssh, Channel *c)
1.41 markus 1213: {
1.410 djm 1214: c->io_want = 0;
1.44 markus 1215: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1216: c->remote_window > 0 &&
1.367 djm 1217: sshbuf_len(c->input) < c->remote_window &&
1218: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1219: c->io_want |= SSH_CHAN_IO_RFD;
1.44 markus 1220: if (c->ostate == CHAN_OUTPUT_OPEN ||
1221: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1222: if (sshbuf_len(c->output) > 0) {
1.410 djm 1223: c->io_want |= SSH_CHAN_IO_WFD;
1.44 markus 1224: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1225: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1226: debug2("channel %d: "
1227: "obuf_empty delayed efd %d/(%zu)", c->self,
1228: c->efd, sshbuf_len(c->extended));
1.172 markus 1229: else
1.367 djm 1230: chan_obuf_empty(ssh, c);
1.44 markus 1231: }
1232: }
1233: /** XXX check close conditions, too */
1.358 djm 1234: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1235: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1236: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1237: sshbuf_len(c->extended) > 0)
1.410 djm 1238: c->io_want |= SSH_CHAN_IO_EFD_W;
1.306 djm 1239: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1240: (c->extended_usage == CHAN_EXTENDED_READ ||
1241: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1242: sshbuf_len(c->extended) < c->remote_window)
1.410 djm 1243: c->io_want |= SSH_CHAN_IO_EFD_R;
1.44 markus 1244: }
1.204 djm 1245: /* XXX: What about efd? races? */
1.44 markus 1246: }
1247:
1.41 markus 1248: /*
1249: * This is a special state for X11 authentication spoofing. An opened X11
1250: * connection (when authentication spoofing is being done) remains in this
1251: * state until the first packet has been completely read. The authentication
1252: * data in that packet is then substituted by the real data if it matches the
1253: * fake data, and the channel is put into normal mode.
1.51 markus 1254: * XXX All this happens at the client side.
1.121 markus 1255: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1256: */
1.127 itojun 1257: static int
1.367 djm 1258: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1259: {
1.367 djm 1260: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1261: u_char *ucp;
1262: u_int proto_len, data_len;
1.25 markus 1263:
1.347 djm 1264: /* Is this being called after the refusal deadline? */
1.367 djm 1265: if (sc->x11_refuse_time != 0 &&
1.428 dtucker 1266: monotime() >= sc->x11_refuse_time) {
1.347 djm 1267: verbose("Rejected X11 connection after ForwardX11Timeout "
1268: "expired");
1269: return -1;
1270: }
1271:
1.41 markus 1272: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1273: if (sshbuf_len(b) < 12)
1.41 markus 1274: return 0;
1275:
1276: /* Parse the lengths of variable-length fields. */
1.367 djm 1277: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1278: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1279: proto_len = 256 * ucp[6] + ucp[7];
1280: data_len = 256 * ucp[8] + ucp[9];
1281: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1282: proto_len = ucp[6] + 256 * ucp[7];
1283: data_len = ucp[8] + 256 * ucp[9];
1284: } else {
1.194 markus 1285: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1286: ucp[0]);
1.41 markus 1287: return -1;
1288: }
1289:
1290: /* Check if the whole packet is in buffer. */
1.367 djm 1291: if (sshbuf_len(b) <
1.41 markus 1292: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1293: return 0;
1294:
1295: /* Check if authentication protocol matches. */
1.367 djm 1296: if (proto_len != strlen(sc->x11_saved_proto) ||
1297: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1298: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1299: return -1;
1300: }
1301: /* Check if authentication data matches our fake data. */
1.367 djm 1302: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1303: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1304: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1305: debug2("X11 auth data does not match fake data.");
1.41 markus 1306: return -1;
1307: }
1308: /* Check fake data length */
1.367 djm 1309: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1310: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1311: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1312: return -1;
1313: }
1314: /*
1315: * Received authentication protocol and data match
1316: * our fake data. Substitute the fake data with real
1317: * data.
1318: */
1319: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1320: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1321: return 1;
1322: }
1323:
1.423 djm 1324: void
1325: channel_force_close(struct ssh *ssh, Channel *c, int abandon)
1326: {
1327: debug3_f("channel %d: forcibly closing", c->self);
1328: if (c->istate == CHAN_INPUT_OPEN)
1329: chan_read_failed(ssh, c);
1330: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1331: sshbuf_reset(c->input);
1332: chan_ibuf_empty(ssh, c);
1333: }
1334: if (c->ostate == CHAN_OUTPUT_OPEN ||
1335: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1336: sshbuf_reset(c->output);
1337: chan_write_failed(ssh, c);
1338: }
1339: if (c->detach_user)
1340: c->detach_user(ssh, c->self, 1, NULL);
1341: if (c->efd != -1)
1342: channel_close_fd(ssh, c, &c->efd);
1343: if (abandon)
1344: c->type = SSH_CHANNEL_ABANDONED;
1.426 djm 1345: /* exempt from inactivity timeouts */
1346: c->inactive_deadline = 0;
1347: c->lastused = 0;
1.423 djm 1348: }
1349:
1.127 itojun 1350: static void
1.410 djm 1351: channel_pre_x11_open(struct ssh *ssh, Channel *c)
1.41 markus 1352: {
1.367 djm 1353: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1354:
1355: /* c->force_drain = 1; */
1356:
1.41 markus 1357: if (ret == 1) {
1358: c->type = SSH_CHANNEL_OPEN;
1.426 djm 1359: c->lastused = monotime();
1.410 djm 1360: channel_pre_open(ssh, c);
1.41 markus 1361: } else if (ret == -1) {
1.423 djm 1362: logit("X11 connection rejected because of wrong "
1363: "authentication.");
1.367 djm 1364: debug2("X11 rejected %d i%d/o%d",
1365: c->self, c->istate, c->ostate);
1.423 djm 1366: channel_force_close(ssh, c, 0);
1.41 markus 1367: }
1368: }
1.25 markus 1369:
1.302 djm 1370: static void
1.410 djm 1371: channel_pre_mux_client(struct ssh *ssh, Channel *c)
1.302 djm 1372: {
1.410 djm 1373: c->io_want = 0;
1.304 djm 1374: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1375: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1376: c->io_want |= SSH_CHAN_IO_RFD;
1.302 djm 1377: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1378: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1379: sshbuf_reset(c->input);
1380: chan_ibuf_empty(ssh, c);
1.302 djm 1381: /* Start output drain. XXX just kill chan? */
1.367 djm 1382: chan_rcvd_oclose(ssh, c);
1.302 djm 1383: }
1384: if (c->ostate == CHAN_OUTPUT_OPEN ||
1385: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1386: if (sshbuf_len(c->output) > 0)
1.410 djm 1387: c->io_want |= SSH_CHAN_IO_WFD;
1.302 djm 1388: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1389: chan_obuf_empty(ssh, c);
1.302 djm 1390: }
1391: }
1392:
1.104 markus 1393: /* try to decode a socks4 header */
1.127 itojun 1394: static int
1.372 markus 1395: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1396: {
1.367 djm 1397: const u_char *p;
1398: char *host;
1.292 djm 1399: u_int len, have, i, found, need;
1.148 deraadt 1400: char username[256];
1.103 markus 1401: struct {
1402: u_int8_t version;
1403: u_int8_t command;
1404: u_int16_t dest_port;
1.104 markus 1405: struct in_addr dest_addr;
1.103 markus 1406: } s4_req, s4_rsp;
1.367 djm 1407: int r;
1.103 markus 1408:
1.104 markus 1409: debug2("channel %d: decode socks4", c->self);
1.109 markus 1410:
1.372 markus 1411: have = sshbuf_len(input);
1.109 markus 1412: len = sizeof(s4_req);
1413: if (have < len)
1414: return 0;
1.372 markus 1415: p = sshbuf_ptr(input);
1.292 djm 1416:
1417: need = 1;
1418: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1419: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1420: debug2("channel %d: socks4a request", c->self);
1421: /* ... and needs an extra string (the hostname) */
1422: need = 2;
1423: }
1424: /* Check for terminating NUL on the string(s) */
1.109 markus 1425: for (found = 0, i = len; i < have; i++) {
1426: if (p[i] == '\0') {
1.292 djm 1427: found++;
1428: if (found == need)
1429: break;
1.109 markus 1430: }
1431: if (i > 1024) {
1432: /* the peer is probably sending garbage */
1433: debug("channel %d: decode socks4: too long",
1434: c->self);
1435: return -1;
1436: }
1437: }
1.292 djm 1438: if (found < need)
1.109 markus 1439: return 0;
1.372 markus 1440: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1441: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1442: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1443: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.403 djm 1444: debug_r(r, "channels %d: decode socks4", c->self);
1.367 djm 1445: return -1;
1446: }
1.372 markus 1447: have = sshbuf_len(input);
1448: p = sshbuf_ptr(input);
1.364 djm 1449: if (memchr(p, '\0', have) == NULL) {
1.403 djm 1450: error("channel %d: decode socks4: unterminated user", c->self);
1.364 djm 1451: return -1;
1452: }
1.103 markus 1453: len = strlen(p);
1.106 markus 1454: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1455: len++; /* trailing '\0' */
1.103 markus 1456: strlcpy(username, p, sizeof(username));
1.403 djm 1457: if ((r = sshbuf_consume(input, len)) != 0)
1458: fatal_fr(r, "channel %d: consume", c->self);
1.321 djm 1459: free(c->path);
1460: c->path = NULL;
1.292 djm 1461: if (need == 1) { /* SOCKS4: one string */
1462: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1463: c->path = xstrdup(host);
1.292 djm 1464: } else { /* SOCKS4A: two strings */
1.372 markus 1465: have = sshbuf_len(input);
1466: p = sshbuf_ptr(input);
1.364 djm 1467: if (memchr(p, '\0', have) == NULL) {
1468: error("channel %d: decode socks4a: host not nul "
1469: "terminated", c->self);
1470: return -1;
1471: }
1.292 djm 1472: len = strlen(p);
1473: debug2("channel %d: decode socks4a: host %s/%d",
1474: c->self, p, len);
1475: len++; /* trailing '\0' */
1.293 djm 1476: if (len > NI_MAXHOST) {
1.292 djm 1477: error("channel %d: hostname \"%.100s\" too long",
1478: c->self, p);
1479: return -1;
1480: }
1.293 djm 1481: c->path = xstrdup(p);
1.403 djm 1482: if ((r = sshbuf_consume(input, len)) != 0)
1483: fatal_fr(r, "channel %d: consume", c->self);
1.292 djm 1484: }
1.103 markus 1485: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1486:
1.194 markus 1487: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1488: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1489:
1.104 markus 1490: if (s4_req.command != 1) {
1.292 djm 1491: debug("channel %d: cannot handle: %s cn %d",
1492: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1493: return -1;
1.103 markus 1494: }
1.104 markus 1495: s4_rsp.version = 0; /* vn: 0 for reply */
1496: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1497: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1498: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.403 djm 1499: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0)
1500: fatal_fr(r, "channel %d: append reply", c->self);
1.104 markus 1501: return 1;
1502: }
1503:
1.193 markus 1504: /* try to decode a socks5 header */
1505: #define SSH_SOCKS5_AUTHDONE 0x1000
1506: #define SSH_SOCKS5_NOAUTH 0x00
1507: #define SSH_SOCKS5_IPV4 0x01
1508: #define SSH_SOCKS5_DOMAIN 0x03
1509: #define SSH_SOCKS5_IPV6 0x04
1510: #define SSH_SOCKS5_CONNECT 0x01
1511: #define SSH_SOCKS5_SUCCESS 0x00
1512:
1513: static int
1.372 markus 1514: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1515: {
1.367 djm 1516: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1517: struct {
1518: u_int8_t version;
1519: u_int8_t command;
1520: u_int8_t reserved;
1521: u_int8_t atyp;
1522: } s5_req, s5_rsp;
1523: u_int16_t dest_port;
1.324 djm 1524: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1525: const u_char *p;
1.252 djm 1526: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1527: int r;
1.193 markus 1528:
1529: debug2("channel %d: decode socks5", c->self);
1.372 markus 1530: p = sshbuf_ptr(input);
1.193 markus 1531: if (p[0] != 0x05)
1532: return -1;
1.372 markus 1533: have = sshbuf_len(input);
1.193 markus 1534: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1535: /* format: ver | nmethods | methods */
1.198 djm 1536: if (have < 2)
1.193 markus 1537: return 0;
1538: nmethods = p[1];
1539: if (have < nmethods + 2)
1540: return 0;
1541: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1542: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1543: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1544: found = 1;
1545: break;
1546: }
1547: }
1548: if (!found) {
1549: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1550: c->self);
1551: return -1;
1552: }
1.403 djm 1553: if ((r = sshbuf_consume(input, nmethods + 2)) != 0)
1554: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1555: /* version, method */
1.372 markus 1556: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1.403 djm 1557: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0)
1558: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1559: c->flags |= SSH_SOCKS5_AUTHDONE;
1560: debug2("channel %d: socks5 auth done", c->self);
1561: return 0; /* need more */
1562: }
1563: debug2("channel %d: socks5 post auth", c->self);
1564: if (have < sizeof(s5_req)+1)
1565: return 0; /* need more */
1.247 deraadt 1566: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1567: if (s5_req.version != 0x05 ||
1568: s5_req.command != SSH_SOCKS5_CONNECT ||
1569: s5_req.reserved != 0x00) {
1.194 markus 1570: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1571: return -1;
1572: }
1.213 deraadt 1573: switch (s5_req.atyp){
1.193 markus 1574: case SSH_SOCKS5_IPV4:
1575: addrlen = 4;
1576: af = AF_INET;
1577: break;
1578: case SSH_SOCKS5_DOMAIN:
1579: addrlen = p[sizeof(s5_req)];
1580: af = -1;
1581: break;
1582: case SSH_SOCKS5_IPV6:
1583: addrlen = 16;
1584: af = AF_INET6;
1585: break;
1586: default:
1.194 markus 1587: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1588: return -1;
1589: }
1.252 djm 1590: need = sizeof(s5_req) + addrlen + 2;
1591: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1592: need++;
1593: if (have < need)
1.193 markus 1594: return 0;
1.403 djm 1595: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0)
1596: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1597: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1598: /* host string length */
1.403 djm 1599: if ((r = sshbuf_consume(input, 1)) != 0)
1600: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1601: }
1.372 markus 1602: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1603: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.403 djm 1604: debug_r(r, "channel %d: parse addr/port", c->self);
1.367 djm 1605: return -1;
1606: }
1.193 markus 1607: dest_addr[addrlen] = '\0';
1.321 djm 1608: free(c->path);
1609: c->path = NULL;
1.293 djm 1610: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1611: if (addrlen >= NI_MAXHOST) {
1.293 djm 1612: error("channel %d: dynamic request: socks5 hostname "
1613: "\"%.100s\" too long", c->self, dest_addr);
1614: return -1;
1615: }
1616: c->path = xstrdup(dest_addr);
1617: } else {
1618: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1619: return -1;
1620: c->path = xstrdup(ntop);
1621: }
1.193 markus 1622: c->host_port = ntohs(dest_port);
1.198 djm 1623:
1.194 markus 1624: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1625: c->self, c->path, c->host_port, s5_req.command);
1626:
1627: s5_rsp.version = 0x05;
1628: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1629: s5_rsp.reserved = 0; /* ignored */
1630: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1631: dest_port = 0; /* ignored */
1632:
1.372 markus 1633: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1634: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1635: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.403 djm 1636: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1637: return 1;
1.301 dtucker 1638: }
1639:
1640: Channel *
1.367 djm 1641: channel_connect_stdio_fwd(struct ssh *ssh,
1.432 dlg 1642: const char *host_to_connect, int port_to_connect,
1.407 djm 1643: int in, int out, int nonblock)
1.301 dtucker 1644: {
1645: Channel *c;
1646:
1.403 djm 1647: debug_f("%s:%d", host_to_connect, port_to_connect);
1.301 dtucker 1648:
1.367 djm 1649: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1650: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.407 djm 1651: 0, "stdio-forward", nonblock);
1.301 dtucker 1652:
1653: c->path = xstrdup(host_to_connect);
1654: c->host_port = port_to_connect;
1655: c->listening_port = 0;
1656: c->force_drain = 1;
1657:
1.367 djm 1658: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1.432 dlg 1659: port_open_helper(ssh, c, port_to_connect == PORT_STREAMLOCAL ?
1660: "direct-streamlocal@openssh.com" : "direct-tcpip");
1.301 dtucker 1661:
1662: return c;
1.193 markus 1663: }
1664:
1.104 markus 1665: /* dynamic port forwarding */
1.127 itojun 1666: static void
1.410 djm 1667: channel_pre_dynamic(struct ssh *ssh, Channel *c)
1.104 markus 1668: {
1.367 djm 1669: const u_char *p;
1.217 djm 1670: u_int have;
1671: int ret;
1.103 markus 1672:
1.410 djm 1673: c->io_want = 0;
1.367 djm 1674: have = sshbuf_len(c->input);
1.104 markus 1675: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1676: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1677: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1678: if (have < 3) {
1.104 markus 1679: /* need more */
1.410 djm 1680: c->io_want |= SSH_CHAN_IO_RFD;
1.104 markus 1681: return;
1682: }
1683: /* try to guess the protocol */
1.367 djm 1684: p = sshbuf_ptr(c->input);
1685: /* XXX sshbuf_peek_u8? */
1.104 markus 1686: switch (p[0]) {
1687: case 0x04:
1.372 markus 1688: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1689: break;
1690: case 0x05:
1.372 markus 1691: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1692: break;
1693: default:
1694: ret = -1;
1695: break;
1696: }
1697: if (ret < 0) {
1.367 djm 1698: chan_mark_dead(ssh, c);
1.104 markus 1699: } else if (ret == 0) {
1700: debug2("channel %d: pre_dynamic: need more", c->self);
1701: /* need more */
1.410 djm 1702: c->io_want |= SSH_CHAN_IO_RFD;
1.372 markus 1703: if (sshbuf_len(c->output))
1.410 djm 1704: c->io_want |= SSH_CHAN_IO_WFD;
1.104 markus 1705: } else {
1706: /* switch to the next state */
1707: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1708: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1709: }
1.103 markus 1710: }
1711:
1.372 markus 1712: /* simulate read-error */
1713: static void
1714: rdynamic_close(struct ssh *ssh, Channel *c)
1715: {
1716: c->type = SSH_CHANNEL_OPEN;
1.423 djm 1717: channel_force_close(ssh, c, 0);
1.372 markus 1718: }
1719:
1720: /* reverse dynamic port forwarding */
1721: static void
1.411 djm 1722: channel_before_prepare_io_rdynamic(struct ssh *ssh, Channel *c)
1.372 markus 1723: {
1724: const u_char *p;
1725: u_int have, len;
1726: int r, ret;
1727:
1728: have = sshbuf_len(c->output);
1729: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1730: /* sshbuf_dump(c->output, stderr); */
1731: /* EOF received */
1732: if (c->flags & CHAN_EOF_RCVD) {
1.403 djm 1733: if ((r = sshbuf_consume(c->output, have)) != 0)
1734: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1735: rdynamic_close(ssh, c);
1736: return;
1737: }
1738: /* check if the fixed size part of the packet is in buffer. */
1739: if (have < 3)
1740: return;
1741: /* try to guess the protocol */
1742: p = sshbuf_ptr(c->output);
1743: switch (p[0]) {
1744: case 0x04:
1745: /* switch input/output for reverse forwarding */
1746: ret = channel_decode_socks4(c, c->output, c->input);
1747: break;
1748: case 0x05:
1749: ret = channel_decode_socks5(c, c->output, c->input);
1750: break;
1751: default:
1752: ret = -1;
1753: break;
1754: }
1755: if (ret < 0) {
1756: rdynamic_close(ssh, c);
1757: } else if (ret == 0) {
1758: debug2("channel %d: pre_rdynamic: need more", c->self);
1759: /* send socks request to peer */
1760: len = sshbuf_len(c->input);
1761: if (len > 0 && len < c->remote_window) {
1762: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1763: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1764: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1765: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 1766: fatal_fr(r, "channel %i: rdynamic", c->self);
1.372 markus 1767: }
1.403 djm 1768: if ((r = sshbuf_consume(c->input, len)) != 0)
1769: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1770: c->remote_window -= len;
1771: }
1772: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1773: /* the connect failed */
1774: rdynamic_close(ssh, c);
1775: }
1776: }
1777:
1.41 markus 1778: /* This is our fake X11 server socket. */
1.127 itojun 1779: static void
1.410 djm 1780: channel_post_x11_listener(struct ssh *ssh, Channel *c)
1.41 markus 1781: {
1.113 markus 1782: Channel *nc;
1.285 djm 1783: struct sockaddr_storage addr;
1.367 djm 1784: int r, newsock, oerrno, remote_port;
1.41 markus 1785: socklen_t addrlen;
1.85 markus 1786: char buf[16384], *remote_ipaddr;
1.25 markus 1787:
1.410 djm 1788: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1789: return;
1790:
1791: debug("X11 connection requested.");
1792: addrlen = sizeof(addr);
1793: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1794: if (c->single_connection) {
1795: oerrno = errno;
1796: debug2("single_connection: closing X11 listener.");
1.407 djm 1797: channel_close_fd(ssh, c, &c->sock);
1.367 djm 1798: chan_mark_dead(ssh, c);
1799: errno = oerrno;
1800: }
1.393 deraadt 1801: if (newsock == -1) {
1.367 djm 1802: if (errno != EINTR && errno != EWOULDBLOCK &&
1803: errno != ECONNABORTED)
1804: error("accept: %.100s", strerror(errno));
1805: if (errno == EMFILE || errno == ENFILE)
1806: c->notbefore = monotime() + 1;
1807: return;
1808: }
1809: set_nodelay(newsock);
1810: remote_ipaddr = get_peer_ipaddr(newsock);
1811: remote_port = get_peer_port(newsock);
1812: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1813: remote_ipaddr, remote_port);
1814:
1.424 djm 1815: nc = channel_new(ssh, "x11-connection",
1.367 djm 1816: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1817: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1818: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1819: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1820: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.403 djm 1821: fatal_fr(r, "channel %i: reply", c->self);
1.41 markus 1822: }
1.367 djm 1823: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1824: fatal_fr(r, "channel %i: send", c->self);
1.367 djm 1825: free(remote_ipaddr);
1.41 markus 1826: }
1.25 markus 1827:
1.127 itojun 1828: static void
1.367 djm 1829: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1830: {
1.328 djm 1831: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1832: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1833: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1834: int remote_port = get_peer_port(c->sock);
1.367 djm 1835: int r;
1.303 djm 1836:
1837: if (remote_port == -1) {
1838: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1839: free(remote_ipaddr);
1.303 djm 1840: remote_ipaddr = xstrdup("127.0.0.1");
1841: remote_port = 65535;
1842: }
1.103 markus 1843:
1.367 djm 1844: free(c->remote_name);
1845: xasprintf(&c->remote_name,
1.103 markus 1846: "%s: listening port %d for %.100s port %d, "
1.328 djm 1847: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1848: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1849: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1850:
1.367 djm 1851: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1852: if (strcmp(rtype, "direct-tcpip") == 0) {
1853: /* target host, port */
1.367 djm 1854: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1855: (r = sshpkt_put_u32(ssh, c->host_port)) != 0)
1856: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1857: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1858: /* target path */
1.403 djm 1859: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1860: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1861: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1862: /* listen path */
1.403 djm 1863: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1864: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1865: } else {
1.358 djm 1866: /* listen address, port */
1.367 djm 1867: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1868: (r = sshpkt_put_u32(ssh, local_port)) != 0)
1869: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1870: }
1871: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1872: /* reserved for future owner/mode info */
1.403 djm 1873: if ((r = sshpkt_put_cstring(ssh, "")) != 0)
1874: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1875: } else {
1876: /* originator host and port */
1.367 djm 1877: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1.403 djm 1878: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0)
1879: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1880: }
1.367 djm 1881: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1882: fatal_fr(r, "channel %i: send", c->self);
1.321 djm 1883: free(remote_ipaddr);
1.328 djm 1884: free(local_ipaddr);
1.103 markus 1885: }
1886:
1.347 djm 1887: void
1.428 dtucker 1888: channel_set_x11_refuse_time(struct ssh *ssh, time_t refuse_time)
1.347 djm 1889: {
1.367 djm 1890: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1891: }
1892:
1.41 markus 1893: /*
1894: * This socket is listening for connections to a forwarded TCP/IP port.
1895: */
1.127 itojun 1896: static void
1.410 djm 1897: channel_post_port_listener(struct ssh *ssh, Channel *c)
1.41 markus 1898: {
1.103 markus 1899: Channel *nc;
1.285 djm 1900: struct sockaddr_storage addr;
1.113 markus 1901: int newsock, nextstate;
1.41 markus 1902: socklen_t addrlen;
1.103 markus 1903: char *rtype;
1.73 markus 1904:
1.410 djm 1905: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1906: return;
1907:
1908: debug("Connection to port %d forwarding to %.100s port %d requested.",
1909: c->listening_port, c->path, c->host_port);
1.103 markus 1910:
1.367 djm 1911: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1912: nextstate = SSH_CHANNEL_OPENING;
1913: rtype = "forwarded-tcpip";
1914: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1915: nextstate = SSH_CHANNEL_OPENING;
1916: rtype = "forwarded-streamlocal@openssh.com";
1917: } else if (c->host_port == PORT_STREAMLOCAL) {
1918: nextstate = SSH_CHANNEL_OPENING;
1919: rtype = "direct-streamlocal@openssh.com";
1920: } else if (c->host_port == 0) {
1921: nextstate = SSH_CHANNEL_DYNAMIC;
1922: rtype = "dynamic-tcpip";
1923: } else {
1924: nextstate = SSH_CHANNEL_OPENING;
1925: rtype = "direct-tcpip";
1926: }
1.103 markus 1927:
1.367 djm 1928: addrlen = sizeof(addr);
1929: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1930: if (newsock == -1) {
1.367 djm 1931: if (errno != EINTR && errno != EWOULDBLOCK &&
1932: errno != ECONNABORTED)
1933: error("accept: %.100s", strerror(errno));
1934: if (errno == EMFILE || errno == ENFILE)
1935: c->notbefore = monotime() + 1;
1936: return;
1.41 markus 1937: }
1.367 djm 1938: if (c->host_port != PORT_STREAMLOCAL)
1939: set_nodelay(newsock);
1940: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1941: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1942: nc->listening_port = c->listening_port;
1943: nc->host_port = c->host_port;
1944: if (c->path != NULL)
1945: nc->path = xstrdup(c->path);
1946:
1947: if (nextstate != SSH_CHANNEL_DYNAMIC)
1948: port_open_helper(ssh, nc, rtype);
1.41 markus 1949: }
1.25 markus 1950:
1.41 markus 1951: /*
1952: * This is the authentication agent socket listening for connections from
1953: * clients.
1954: */
1.127 itojun 1955: static void
1.410 djm 1956: channel_post_auth_listener(struct ssh *ssh, Channel *c)
1.41 markus 1957: {
1.113 markus 1958: Channel *nc;
1.367 djm 1959: int r, newsock;
1.285 djm 1960: struct sockaddr_storage addr;
1.41 markus 1961: socklen_t addrlen;
1.25 markus 1962:
1.410 djm 1963: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1964: return;
1965:
1966: addrlen = sizeof(addr);
1967: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1968: if (newsock == -1) {
1.367 djm 1969: error("accept from auth socket: %.100s", strerror(errno));
1970: if (errno == EMFILE || errno == ENFILE)
1971: c->notbefore = monotime() + 1;
1972: return;
1.41 markus 1973: }
1.424 djm 1974: nc = channel_new(ssh, "agent-connection",
1.367 djm 1975: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1976: c->local_window_max, c->local_maxpacket,
1977: 0, "accepted auth socket", 1);
1978: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1979: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1980: fatal_fr(r, "channel %i", c->self);
1.41 markus 1981: }
1.25 markus 1982:
1.127 itojun 1983: static void
1.410 djm 1984: channel_post_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1985: {
1.372 markus 1986: int err = 0, sock, isopen, r;
1.129 stevesk 1987: socklen_t sz = sizeof(err);
1.114 markus 1988:
1.410 djm 1989: if ((c->io_ready & SSH_CHAN_IO_SOCK_W) == 0)
1.367 djm 1990: return;
1.368 djm 1991: if (!c->have_remote_id)
1.403 djm 1992: fatal_f("channel %d: no remote id", c->self);
1.372 markus 1993: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1994: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.429 djm 1995:
1.393 deraadt 1996: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 1997: err = errno;
1998: error("getsockopt SO_ERROR failed");
1999: }
1.429 djm 2000:
1.367 djm 2001: if (err == 0) {
1.429 djm 2002: /* Non-blocking connection completed */
1.367 djm 2003: debug("channel %d: connected to %s port %d",
2004: c->self, c->connect_ctx.host, c->connect_ctx.port);
2005: channel_connect_ctx_free(&c->connect_ctx);
2006: c->type = SSH_CHANNEL_OPEN;
1.426 djm 2007: c->lastused = monotime();
1.372 markus 2008: if (isopen) {
2009: /* no message necessary */
2010: } else {
2011: if ((r = sshpkt_start(ssh,
2012: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
2013: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2014: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
2015: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 2016: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0 ||
2017: (r = sshpkt_send(ssh)) != 0)
2018: fatal_fr(r, "channel %i open confirm", c->self);
1.367 djm 2019: }
1.429 djm 2020: return;
2021: }
2022: if (err == EINTR || err == EAGAIN || err == EINPROGRESS)
2023: return;
2024:
2025: /* Non-blocking connection failed */
2026: debug("channel %d: connection failed: %s", c->self, strerror(err));
2027:
2028: /* Try next address, if any */
2029: if ((sock = connect_next(&c->connect_ctx)) == -1) {
2030: /* Exhausted all addresses for this destination */
1.367 djm 2031: error("connect_to %.100s port %d: failed.",
2032: c->connect_ctx.host, c->connect_ctx.port);
2033: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 2034: if (isopen) {
2035: rdynamic_close(ssh, c);
2036: } else {
2037: if ((r = sshpkt_start(ssh,
2038: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
2039: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 2040: (r = sshpkt_put_u32(ssh,
2041: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
2042: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1.403 djm 2043: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2044: (r = sshpkt_send(ssh)) != 0)
2045: fatal_fr(r, "channel %i: failure", c->self);
1.372 markus 2046: chan_mark_dead(ssh, c);
1.75 markus 2047: }
2048: }
1.429 djm 2049:
2050: /* New non-blocking connection in progress */
2051: close(c->sock);
2052: c->sock = c->rfd = c->wfd = sock;
1.75 markus 2053: }
2054:
1.127 itojun 2055: static int
1.410 djm 2056: channel_handle_rfd(struct ssh *ssh, Channel *c)
1.41 markus 2057: {
1.214 markus 2058: char buf[CHAN_RBUF];
1.367 djm 2059: ssize_t len;
2060: int r;
1.426 djm 2061: size_t nr = 0, have, avail, maxlen = CHANNEL_MAX_READ;
1.25 markus 2062:
1.410 djm 2063: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.412 djm 2064: return 1; /* Shouldn't happen */
2065: if ((avail = sshbuf_avail(c->input)) == 0)
2066: return 1; /* Shouldn't happen */
2067:
2068: /*
2069: * For "simple" channels (i.e. not datagram or filtered), we can
2070: * read directly to the channel buffer.
2071: */
2072: if (c->input_filter == NULL && !c->datagram) {
2073: /* Only OPEN channels have valid rwin */
2074: if (c->type == SSH_CHANNEL_OPEN) {
2075: if ((have = sshbuf_len(c->input)) >= c->remote_window)
2076: return 1; /* shouldn't happen */
2077: if (maxlen > c->remote_window - have)
2078: maxlen = c->remote_window - have;
2079: }
2080: if (maxlen > avail)
2081: maxlen = avail;
1.426 djm 2082: if ((r = sshbuf_read(c->rfd, c->input, maxlen, &nr)) != 0) {
1.413 djm 2083: if (errno == EINTR || errno == EAGAIN)
2084: return 1;
1.412 djm 2085: debug2("channel %d: read failed rfd %d maxlen %zu: %s",
2086: c->self, c->rfd, maxlen, ssh_err(r));
2087: goto rfail;
2088: }
1.426 djm 2089: if (nr != 0)
2090: c->lastused = monotime();
1.367 djm 2091: return 1;
1.412 djm 2092: }
1.367 djm 2093:
2094: len = read(c->rfd, buf, sizeof(buf));
1.393 deraadt 2095: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2096: return 1;
2097: if (len <= 0) {
1.412 djm 2098: debug2("channel %d: read<=0 rfd %d len %zd: %s",
2099: c->self, c->rfd, len,
2100: len == 0 ? "closed" : strerror(errno));
2101: rfail:
1.367 djm 2102: if (c->type != SSH_CHANNEL_OPEN) {
2103: debug2("channel %d: not open", c->self);
2104: chan_mark_dead(ssh, c);
1.41 markus 2105: return -1;
1.65 markus 2106: } else {
1.367 djm 2107: chan_read_failed(ssh, c);
1.65 markus 2108: }
1.367 djm 2109: return -1;
2110: }
1.426 djm 2111: c->lastused = monotime();
1.367 djm 2112: if (c->input_filter != NULL) {
2113: if (c->input_filter(ssh, c, buf, len) == -1) {
2114: debug2("channel %d: filter stops", c->self);
2115: chan_read_failed(ssh, c);
2116: }
2117: } else if (c->datagram) {
2118: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1.403 djm 2119: fatal_fr(r, "channel %i: put datagram", c->self);
1.412 djm 2120: }
1.41 markus 2121: return 1;
2122: }
1.241 deraadt 2123:
1.127 itojun 2124: static int
1.410 djm 2125: channel_handle_wfd(struct ssh *ssh, Channel *c)
1.41 markus 2126: {
1.95 markus 2127: struct termios tio;
1.367 djm 2128: u_char *data = NULL, *buf; /* XXX const; need filter API change */
2129: size_t dlen, olen = 0;
2130: int r, len;
2131:
1.410 djm 2132: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
2133: return 1;
2134: if (sshbuf_len(c->output) == 0)
1.367 djm 2135: return 1;
1.25 markus 2136:
1.41 markus 2137: /* Send buffered output data to the socket. */
1.367 djm 2138: olen = sshbuf_len(c->output);
2139: if (c->output_filter != NULL) {
2140: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
2141: debug2("channel %d: filter stops", c->self);
2142: if (c->type != SSH_CHANNEL_OPEN)
2143: chan_mark_dead(ssh, c);
2144: else
2145: chan_write_failed(ssh, c);
2146: return -1;
1.231 reyk 2147: }
1.367 djm 2148: } else if (c->datagram) {
2149: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1.403 djm 2150: fatal_fr(r, "channel %i: get datagram", c->self);
1.369 djm 2151: buf = data;
1.367 djm 2152: } else {
2153: buf = data = sshbuf_mutable_ptr(c->output);
2154: dlen = sshbuf_len(c->output);
2155: }
1.231 reyk 2156:
1.367 djm 2157: if (c->datagram) {
2158: /* ignore truncated writes, datagrams might get lost */
1.374 djm 2159: len = write(c->wfd, buf, dlen);
1.367 djm 2160: free(data);
1.393 deraadt 2161: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 2162: return 1;
1.367 djm 2163: if (len <= 0)
2164: goto write_fail;
2165: goto out;
2166: }
2167:
2168: len = write(c->wfd, buf, dlen);
1.393 deraadt 2169: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2170: return 1;
2171: if (len <= 0) {
2172: write_fail:
2173: if (c->type != SSH_CHANNEL_OPEN) {
2174: debug2("channel %d: not open", c->self);
2175: chan_mark_dead(ssh, c);
1.41 markus 2176: return -1;
1.367 djm 2177: } else {
2178: chan_write_failed(ssh, c);
1.91 markus 2179: }
1.367 djm 2180: return -1;
2181: }
1.426 djm 2182: c->lastused = monotime();
1.367 djm 2183: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2184: if (tcgetattr(c->wfd, &tio) == 0 &&
2185: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2186: /*
2187: * Simulate echo to reduce the impact of
2188: * traffic analysis. We need to match the
2189: * size of a SSH2_MSG_CHANNEL_DATA message
2190: * (4 byte channel id + buf)
2191: */
2192: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2193: (r = sshpkt_send(ssh)) != 0)
1.403 djm 2194: fatal_fr(r, "channel %i: ignore", c->self);
1.25 markus 2195: }
1.367 djm 2196: }
1.403 djm 2197: if ((r = sshbuf_consume(c->output, len)) != 0)
2198: fatal_fr(r, "channel %i: consume", c->self);
1.309 djm 2199: out:
1.367 djm 2200: c->local_consumed += olen - sshbuf_len(c->output);
2201:
2202: return 1;
2203: }
2204:
2205: static int
1.410 djm 2206: channel_handle_efd_write(struct ssh *ssh, Channel *c)
1.367 djm 2207: {
2208: int r;
2209: ssize_t len;
2210:
1.410 djm 2211: if ((c->io_ready & SSH_CHAN_IO_EFD_W) == 0)
2212: return 1;
2213: if (sshbuf_len(c->extended) == 0)
1.367 djm 2214: return 1;
2215:
2216: len = write(c->efd, sshbuf_ptr(c->extended),
2217: sshbuf_len(c->extended));
2218: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 deraadt 2219: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2220: return 1;
2221: if (len <= 0) {
2222: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1.407 djm 2223: channel_close_fd(ssh, c, &c->efd);
1.367 djm 2224: } else {
1.403 djm 2225: if ((r = sshbuf_consume(c->extended, len)) != 0)
2226: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2227: c->local_consumed += len;
1.426 djm 2228: c->lastused = monotime();
1.367 djm 2229: }
1.44 markus 2230: return 1;
2231: }
1.241 deraadt 2232:
1.127 itojun 2233: static int
1.410 djm 2234: channel_handle_efd_read(struct ssh *ssh, Channel *c)
1.44 markus 2235: {
1.214 markus 2236: char buf[CHAN_RBUF];
1.367 djm 2237: int r;
2238: ssize_t len;
2239:
1.410 djm 2240: if ((c->io_ready & SSH_CHAN_IO_EFD_R) == 0)
1.367 djm 2241: return 1;
1.44 markus 2242:
1.367 djm 2243: len = read(c->efd, buf, sizeof(buf));
2244: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 deraadt 2245: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2246: return 1;
2247: if (len <= 0) {
1.403 djm 2248: debug2("channel %d: closing read-efd %d", c->self, c->efd);
1.407 djm 2249: channel_close_fd(ssh, c, &c->efd);
1.426 djm 2250: return 1;
2251: }
2252: c->lastused = monotime();
2253: if (c->extended_usage == CHAN_EXTENDED_IGNORE)
1.403 djm 2254: debug3("channel %d: discard efd", c->self);
2255: else if ((r = sshbuf_put(c->extended, buf, len)) != 0)
2256: fatal_fr(r, "channel %i: append", c->self);
1.44 markus 2257: return 1;
2258: }
1.241 deraadt 2259:
1.127 itojun 2260: static int
1.410 djm 2261: channel_handle_efd(struct ssh *ssh, Channel *c)
1.44 markus 2262: {
1.367 djm 2263: if (c->efd == -1)
2264: return 1;
2265:
2266: /** XXX handle drain efd, too */
2267:
2268: if (c->extended_usage == CHAN_EXTENDED_WRITE)
1.410 djm 2269: return channel_handle_efd_write(ssh, c);
1.367 djm 2270: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2271: c->extended_usage == CHAN_EXTENDED_IGNORE)
1.410 djm 2272: return channel_handle_efd_read(ssh, c);
1.367 djm 2273:
2274: return 1;
2275: }
2276:
2277: static int
2278: channel_check_window(struct ssh *ssh, Channel *c)
2279: {
2280: int r;
2281:
1.104 markus 2282: if (c->type == SSH_CHANNEL_OPEN &&
2283: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2284: ((c->local_window_max - c->local_window >
1.269 markus 2285: c->local_maxpacket*3) ||
2286: c->local_window < c->local_window_max/2) &&
1.44 markus 2287: c->local_consumed > 0) {
1.368 djm 2288: if (!c->have_remote_id)
1.403 djm 2289: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2290: if ((r = sshpkt_start(ssh,
2291: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2292: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2293: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2294: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2295: fatal_fr(r, "channel %i", c->self);
1.367 djm 2296: }
1.403 djm 2297: debug2("channel %d: window %d sent adjust %d", c->self,
2298: c->local_window, c->local_consumed);
1.44 markus 2299: c->local_window += c->local_consumed;
2300: c->local_consumed = 0;
1.1 deraadt 2301: }
1.41 markus 2302: return 1;
1.1 deraadt 2303: }
2304:
1.127 itojun 2305: static void
1.410 djm 2306: channel_post_open(struct ssh *ssh, Channel *c)
1.41 markus 2307: {
1.410 djm 2308: channel_handle_rfd(ssh, c);
2309: channel_handle_wfd(ssh, c);
2310: channel_handle_efd(ssh, c);
1.367 djm 2311: channel_check_window(ssh, c);
1.44 markus 2312: }
2313:
1.302 djm 2314: static u_int
1.367 djm 2315: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2316: {
2317: char buf[CHAN_RBUF];
1.367 djm 2318: ssize_t len;
1.302 djm 2319: u_int rlen;
1.367 djm 2320: int r;
1.302 djm 2321:
1.367 djm 2322: if (sshbuf_len(c->input) < need) {
2323: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2324: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 deraadt 2325: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2326: return sshbuf_len(c->input);
1.302 djm 2327: if (len <= 0) {
1.367 djm 2328: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2329: c->self, c->rfd, len);
1.367 djm 2330: chan_read_failed(ssh, c);
1.349 naddy 2331: return 0;
1.403 djm 2332: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
2333: fatal_fr(r, "channel %i: append", c->self);
1.302 djm 2334: }
1.367 djm 2335: return sshbuf_len(c->input);
1.302 djm 2336: }
2337:
2338: static void
1.410 djm 2339: channel_post_mux_client_read(struct ssh *ssh, Channel *c)
1.302 djm 2340: {
2341: u_int need;
2342:
1.410 djm 2343: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.367 djm 2344: return;
2345: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2346: return;
2347: if (c->mux_pause)
2348: return;
2349:
2350: /*
2351: * Don't not read past the precise end of packets to
2352: * avoid disrupting fd passing.
2353: */
2354: if (read_mux(ssh, c, 4) < 4) /* read header */
2355: return;
2356: /* XXX sshbuf_peek_u32 */
2357: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2358: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2359: if (need > CHANNEL_MUX_MAX_PACKET) {
2360: debug2("channel %d: packet too big %u > %u",
2361: c->self, CHANNEL_MUX_MAX_PACKET, need);
2362: chan_rcvd_oclose(ssh, c);
2363: return;
2364: }
2365: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2366: return;
2367: if (c->mux_rcb(ssh, c) != 0) {
2368: debug("channel %d: mux_rcb failed", c->self);
2369: chan_mark_dead(ssh, c);
2370: return;
1.302 djm 2371: }
1.367 djm 2372: }
2373:
2374: static void
1.410 djm 2375: channel_post_mux_client_write(struct ssh *ssh, Channel *c)
1.367 djm 2376: {
2377: ssize_t len;
2378: int r;
1.302 djm 2379:
1.410 djm 2380: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
2381: return;
2382: if (sshbuf_len(c->output) == 0)
1.367 djm 2383: return;
2384:
2385: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 deraadt 2386: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2387: return;
2388: if (len <= 0) {
2389: chan_mark_dead(ssh, c);
2390: return;
1.302 djm 2391: }
1.367 djm 2392: if ((r = sshbuf_consume(c->output, len)) != 0)
1.403 djm 2393: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2394: }
2395:
2396: static void
1.410 djm 2397: channel_post_mux_client(struct ssh *ssh, Channel *c)
1.367 djm 2398: {
1.410 djm 2399: channel_post_mux_client_read(ssh, c);
2400: channel_post_mux_client_write(ssh, c);
1.302 djm 2401: }
2402:
2403: static void
1.410 djm 2404: channel_post_mux_listener(struct ssh *ssh, Channel *c)
1.302 djm 2405: {
2406: Channel *nc;
2407: struct sockaddr_storage addr;
2408: socklen_t addrlen;
2409: int newsock;
2410: uid_t euid;
2411: gid_t egid;
2412:
1.410 djm 2413: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.302 djm 2414: return;
2415:
2416: debug("multiplexing control connection");
2417:
2418: /*
2419: * Accept connection on control socket
2420: */
2421: memset(&addr, 0, sizeof(addr));
2422: addrlen = sizeof(addr);
2423: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2424: &addrlen)) == -1) {
1.403 djm 2425: error_f("accept: %s", strerror(errno));
1.317 djm 2426: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2427: c->notbefore = monotime() + 1;
1.302 djm 2428: return;
2429: }
2430:
1.393 deraadt 2431: if (getpeereid(newsock, &euid, &egid) == -1) {
1.403 djm 2432: error_f("getpeereid failed: %s", strerror(errno));
1.302 djm 2433: close(newsock);
2434: return;
2435: }
2436: if ((euid != 0) && (getuid() != euid)) {
2437: error("multiplex uid mismatch: peer euid %u != uid %u",
2438: (u_int)euid, (u_int)getuid());
2439: close(newsock);
2440: return;
2441: }
1.424 djm 2442: nc = channel_new(ssh, "mux-control", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2443: newsock, newsock, -1, c->local_window_max,
2444: c->local_maxpacket, 0, "mux-control", 1);
2445: nc->mux_rcb = c->mux_rcb;
1.403 djm 2446: debug3_f("new mux channel %d fd %d", nc->self, nc->sock);
1.302 djm 2447: /* establish state */
1.367 djm 2448: nc->mux_rcb(ssh, nc);
1.302 djm 2449: /* mux state transitions must not elicit protocol messages */
2450: nc->flags |= CHAN_LOCAL;
2451: }
2452:
1.127 itojun 2453: static void
1.367 djm 2454: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2455: {
1.367 djm 2456: chan_fn **pre, **post;
2457:
2458: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
1.406 djm 2459: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
1.403 djm 2460: fatal_f("allocation failed");
1.367 djm 2461:
2462: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2463: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2464: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2465: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2466: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2467: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2468: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2469: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2470: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2471: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2472: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2473: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2474: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2475:
2476: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2477: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2478: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2479: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2480: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2481: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2482: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2483: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2484: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2485: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2486: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2487: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2488:
1.367 djm 2489: sc->channel_pre = pre;
2490: sc->channel_post = post;
1.44 markus 2491: }
2492:
1.140 markus 2493: /* gc dead channels */
2494: static void
1.367 djm 2495: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2496: {
2497: if (c == NULL)
2498: return;
2499: if (c->detach_user != NULL) {
1.367 djm 2500: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2501: return;
1.385 djm 2502:
1.194 markus 2503: debug2("channel %d: gc: notify user", c->self);
1.423 djm 2504: c->detach_user(ssh, c->self, 0, NULL);
1.140 markus 2505: /* if we still have a callback */
2506: if (c->detach_user != NULL)
2507: return;
1.194 markus 2508: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2509: }
1.367 djm 2510: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2511: return;
1.194 markus 2512: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2513: channel_free(ssh, c);
1.140 markus 2514: }
2515:
1.367 djm 2516: enum channel_table { CHAN_PRE, CHAN_POST };
2517:
1.127 itojun 2518: static void
1.422 djm 2519: channel_handler(struct ssh *ssh, int table, struct timespec *timeout)
1.41 markus 2520: {
1.367 djm 2521: struct ssh_channels *sc = ssh->chanctxt;
2522: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2523: u_int i, oalloc;
1.41 markus 2524: Channel *c;
1.317 djm 2525: time_t now;
1.25 markus 2526:
1.322 dtucker 2527: now = monotime();
1.367 djm 2528: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2529: c = sc->channels[i];
1.113 markus 2530: if (c == NULL)
1.41 markus 2531: continue;
1.417 djm 2532: /* Try to keep IO going while rekeying */
2533: if (ssh_packet_is_rekeying(ssh) && c->type != SSH_CHANNEL_OPEN)
2534: continue;
1.299 markus 2535: if (c->delayed) {
1.367 djm 2536: if (table == CHAN_PRE)
1.299 markus 2537: c->delayed = 0;
2538: else
2539: continue;
2540: }
1.317 djm 2541: if (ftab[c->type] != NULL) {
1.426 djm 2542: if (table == CHAN_PRE &&
2543: c->type == SSH_CHANNEL_OPEN &&
2544: c->inactive_deadline != 0 && c->lastused != 0 &&
2545: now >= c->lastused + c->inactive_deadline) {
2546: /* channel closed for inactivity */
2547: verbose("channel %d: closing after %u seconds "
2548: "of inactivity", c->self,
2549: c->inactive_deadline);
2550: channel_force_close(ssh, c, 1);
2551: } else if (c->notbefore <= now) {
2552: /* Run handlers that are not paused. */
1.410 djm 2553: (*ftab[c->type])(ssh, c);
1.426 djm 2554: /* inactivity timeouts must interrupt poll() */
2555: if (timeout != NULL &&
2556: c->type == SSH_CHANNEL_OPEN &&
2557: c->lastused != 0 &&
2558: c->inactive_deadline != 0) {
2559: ptimeout_deadline_monotime(timeout,
2560: c->lastused + c->inactive_deadline);
2561: }
2562: } else if (timeout != NULL) {
1.317 djm 2563: /*
1.426 djm 2564: * Arrange for poll() wakeup when channel pause
1.422 djm 2565: * timer expires.
1.317 djm 2566: */
1.422 djm 2567: ptimeout_deadline_monotime(timeout,
2568: c->notbefore);
1.317 djm 2569: }
2570: }
1.367 djm 2571: channel_garbage_collect(ssh, c);
1.1 deraadt 2572: }
2573: }
2574:
1.121 markus 2575: /*
1.411 djm 2576: * Create sockets before preparing IO.
1.372 markus 2577: * This is necessary for things that need to happen after reading
1.411 djm 2578: * the network-input but need to be completed before IO event setup, e.g.
2579: * because they may create new channels.
1.372 markus 2580: */
2581: static void
1.411 djm 2582: channel_before_prepare_io(struct ssh *ssh)
1.372 markus 2583: {
2584: struct ssh_channels *sc = ssh->chanctxt;
2585: Channel *c;
2586: u_int i, oalloc;
2587:
2588: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2589: c = sc->channels[i];
2590: if (c == NULL)
2591: continue;
2592: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
1.411 djm 2593: channel_before_prepare_io_rdynamic(ssh, c);
2594: }
2595: }
2596:
2597: static void
2598: dump_channel_poll(const char *func, const char *what, Channel *c,
2599: u_int pollfd_offset, struct pollfd *pfd)
2600: {
2601: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2602: debug3("%s: channel %d: %s r%d w%d e%d s%d c->pfds [ %d %d %d %d ] "
2603: "io_want 0x%02x io_ready 0x%02x pfd[%u].fd=%d "
2604: "pfd.ev 0x%02x pfd.rev 0x%02x", func, c->self, what,
2605: c->rfd, c->wfd, c->efd, c->sock,
2606: c->pfds[0], c->pfds[1], c->pfds[2], c->pfds[3],
2607: c->io_want, c->io_ready,
2608: pollfd_offset, pfd->fd, pfd->events, pfd->revents);
1.411 djm 2609: #endif
2610: }
2611:
2612: /* Prepare pollfd entries for a single channel */
2613: static void
2614: channel_prepare_pollfd(Channel *c, u_int *next_pollfd,
2615: struct pollfd *pfd, u_int npfd)
2616: {
1.415 djm 2617: u_int ev, p = *next_pollfd;
1.411 djm 2618:
2619: if (c == NULL)
2620: return;
2621: if (p + 4 > npfd) {
2622: /* Shouldn't happen */
2623: fatal_f("channel %d: bad pfd offset %u (max %u)",
2624: c->self, p, npfd);
2625: }
1.415 djm 2626: c->pfds[0] = c->pfds[1] = c->pfds[2] = c->pfds[3] = -1;
1.411 djm 2627: /*
2628: * prepare c->rfd
2629: *
2630: * This is a special case, since c->rfd might be the same as
2631: * c->wfd, c->efd and/or c->sock. Handle those here if they want
2632: * IO too.
2633: */
2634: if (c->rfd != -1) {
1.415 djm 2635: ev = 0;
1.411 djm 2636: if ((c->io_want & SSH_CHAN_IO_RFD) != 0)
1.415 djm 2637: ev |= POLLIN;
1.411 djm 2638: /* rfd == wfd */
1.415 djm 2639: if (c->wfd == c->rfd) {
2640: if ((c->io_want & SSH_CHAN_IO_WFD) != 0)
2641: ev |= POLLOUT;
2642: }
1.411 djm 2643: /* rfd == efd */
1.415 djm 2644: if (c->efd == c->rfd) {
2645: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
2646: ev |= POLLIN;
2647: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
2648: ev |= POLLOUT;
2649: }
1.411 djm 2650: /* rfd == sock */
1.415 djm 2651: if (c->sock == c->rfd) {
2652: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
2653: ev |= POLLIN;
2654: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
2655: ev |= POLLOUT;
2656: }
2657: /* Pack a pfd entry if any event armed for this fd */
2658: if (ev != 0) {
2659: c->pfds[0] = p;
2660: pfd[p].fd = c->rfd;
2661: pfd[p].events = ev;
2662: dump_channel_poll(__func__, "rfd", c, p, &pfd[p]);
2663: p++;
2664: }
1.411 djm 2665: }
1.415 djm 2666: /* prepare c->wfd if wanting IO and not already handled above */
1.411 djm 2667: if (c->wfd != -1 && c->rfd != c->wfd) {
1.415 djm 2668: ev = 0;
2669: if ((c->io_want & SSH_CHAN_IO_WFD))
2670: ev |= POLLOUT;
2671: /* Pack a pfd entry if any event armed for this fd */
2672: if (ev != 0) {
2673: c->pfds[1] = p;
2674: pfd[p].fd = c->wfd;
2675: pfd[p].events = ev;
2676: dump_channel_poll(__func__, "wfd", c, p, &pfd[p]);
2677: p++;
2678: }
1.411 djm 2679: }
1.415 djm 2680: /* prepare c->efd if wanting IO and not already handled above */
1.411 djm 2681: if (c->efd != -1 && c->rfd != c->efd) {
1.415 djm 2682: ev = 0;
1.411 djm 2683: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
1.415 djm 2684: ev |= POLLIN;
1.411 djm 2685: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
1.415 djm 2686: ev |= POLLOUT;
2687: /* Pack a pfd entry if any event armed for this fd */
2688: if (ev != 0) {
2689: c->pfds[2] = p;
2690: pfd[p].fd = c->efd;
2691: pfd[p].events = ev;
2692: dump_channel_poll(__func__, "efd", c, p, &pfd[p]);
2693: p++;
2694: }
1.411 djm 2695: }
1.415 djm 2696: /* prepare c->sock if wanting IO and not already handled above */
1.411 djm 2697: if (c->sock != -1 && c->rfd != c->sock) {
1.415 djm 2698: ev = 0;
1.411 djm 2699: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
1.415 djm 2700: ev |= POLLIN;
1.411 djm 2701: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
1.415 djm 2702: ev |= POLLOUT;
2703: /* Pack a pfd entry if any event armed for this fd */
2704: if (ev != 0) {
2705: c->pfds[3] = p;
2706: pfd[p].fd = c->sock;
2707: pfd[p].events = 0;
2708: dump_channel_poll(__func__, "sock", c, p, &pfd[p]);
2709: p++;
2710: }
1.372 markus 2711: }
1.411 djm 2712: *next_pollfd = p;
1.372 markus 2713: }
2714:
1.411 djm 2715: /* * Allocate/prepare poll structure */
1.49 markus 2716: void
1.411 djm 2717: channel_prepare_poll(struct ssh *ssh, struct pollfd **pfdp, u_int *npfd_allocp,
1.422 djm 2718: u_int *npfd_activep, u_int npfd_reserved, struct timespec *timeout)
1.41 markus 2719: {
1.410 djm 2720: struct ssh_channels *sc = ssh->chanctxt;
1.411 djm 2721: u_int i, oalloc, p, npfd = npfd_reserved;
2722:
2723: channel_before_prepare_io(ssh); /* might create a new channel */
1.416 djm 2724: /* clear out I/O flags from last poll */
2725: for (i = 0; i < sc->channels_alloc; i++) {
2726: if (sc->channels[i] == NULL)
2727: continue;
2728: sc->channels[i]->io_want = sc->channels[i]->io_ready = 0;
2729: }
1.411 djm 2730: /* Allocate 4x pollfd for each channel (rfd, wfd, efd, sock) */
2731: if (sc->channels_alloc >= (INT_MAX / 4) - npfd_reserved)
2732: fatal_f("too many channels"); /* shouldn't happen */
1.417 djm 2733: npfd += sc->channels_alloc * 4;
1.411 djm 2734: if (npfd > *npfd_allocp) {
2735: *pfdp = xrecallocarray(*pfdp, *npfd_allocp,
2736: npfd, sizeof(**pfdp));
2737: *npfd_allocp = npfd;
2738: }
2739: *npfd_activep = npfd_reserved;
2740: oalloc = sc->channels_alloc;
1.372 markus 2741:
1.422 djm 2742: channel_handler(ssh, CHAN_PRE, timeout);
1.84 markus 2743:
1.411 djm 2744: if (oalloc != sc->channels_alloc) {
2745: /* shouldn't happen */
2746: fatal_f("channels_alloc changed during CHAN_PRE "
2747: "(was %u, now %u)", oalloc, sc->channels_alloc);
2748: }
1.84 markus 2749:
1.411 djm 2750: /* Prepare pollfd */
2751: p = npfd_reserved;
2752: for (i = 0; i < sc->channels_alloc; i++)
2753: channel_prepare_pollfd(sc->channels[i], &p, *pfdp, npfd);
2754: *npfd_activep = p;
2755: }
2756:
2757: static void
1.415 djm 2758: fd_ready(Channel *c, int p, struct pollfd *pfds, u_int npfd, int fd,
1.411 djm 2759: const char *what, u_int revents_mask, u_int ready)
2760: {
2761: struct pollfd *pfd = &pfds[p];
1.410 djm 2762:
1.411 djm 2763: if (fd == -1)
2764: return;
1.415 djm 2765: if (p == -1 || (u_int)p >= npfd)
2766: fatal_f("channel %d: bad pfd %d (max %u)", c->self, p, npfd);
1.411 djm 2767: dump_channel_poll(__func__, what, c, p, pfd);
2768: if (pfd->fd != fd) {
2769: fatal("channel %d: inconsistent %s fd=%d pollfd[%u].fd %d "
2770: "r%d w%d e%d s%d", c->self, what, fd, p, pfd->fd,
2771: c->rfd, c->wfd, c->efd, c->sock);
2772: }
2773: if ((pfd->revents & POLLNVAL) != 0) {
2774: fatal("channel %d: invalid %s pollfd[%u].fd %d r%d w%d e%d s%d",
2775: c->self, what, p, pfd->fd, c->rfd, c->wfd, c->efd, c->sock);
1.410 djm 2776: }
1.411 djm 2777: if ((pfd->revents & (revents_mask|POLLHUP|POLLERR)) != 0)
2778: c->io_ready |= ready & c->io_want;
1.41 markus 2779: }
2780:
1.121 markus 2781: /*
1.411 djm 2782: * After poll, perform any appropriate operations for channels which have
1.121 markus 2783: * events pending.
2784: */
1.49 markus 2785: void
1.411 djm 2786: channel_after_poll(struct ssh *ssh, struct pollfd *pfd, u_int npfd)
1.41 markus 2787: {
1.410 djm 2788: struct ssh_channels *sc = ssh->chanctxt;
1.415 djm 2789: u_int i;
2790: int p;
1.410 djm 2791: Channel *c;
2792:
1.411 djm 2793: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2794: for (p = 0; p < (int)npfd; p++) {
1.411 djm 2795: if (pfd[p].revents == 0)
2796: continue;
2797: debug_f("pfd[%u].fd %d rev 0x%04x",
2798: p, pfd[p].fd, pfd[p].revents);
2799: }
2800: #endif
2801:
2802: /* Convert pollfd into c->io_ready */
2803: for (i = 0; i < sc->channels_alloc; i++) {
1.410 djm 2804: c = sc->channels[i];
1.415 djm 2805: if (c == NULL)
1.410 djm 2806: continue;
1.411 djm 2807: /* if rfd is shared with efd/sock then wfd should be too */
2808: if (c->rfd != -1 && c->wfd != -1 && c->rfd != c->wfd &&
2809: (c->rfd == c->efd || c->rfd == c->sock)) {
2810: /* Shouldn't happen */
2811: fatal_f("channel %d: unexpected fds r%d w%d e%d s%d",
2812: c->self, c->rfd, c->wfd, c->efd, c->sock);
2813: }
1.410 djm 2814: c->io_ready = 0;
1.411 djm 2815: /* rfd, potentially shared with wfd, efd and sock */
1.415 djm 2816: if (c->rfd != -1 && (p = c->pfds[0]) != -1) {
2817: fd_ready(c, p, pfd, npfd, c->rfd,
2818: "rfd", POLLIN, SSH_CHAN_IO_RFD);
1.411 djm 2819: if (c->rfd == c->wfd) {
1.415 djm 2820: fd_ready(c, p, pfd, npfd, c->wfd,
2821: "wfd/r", POLLOUT, SSH_CHAN_IO_WFD);
1.411 djm 2822: }
2823: if (c->rfd == c->efd) {
1.415 djm 2824: fd_ready(c, p, pfd, npfd, c->efd,
2825: "efdr/r", POLLIN, SSH_CHAN_IO_EFD_R);
2826: fd_ready(c, p, pfd, npfd, c->efd,
2827: "efdw/r", POLLOUT, SSH_CHAN_IO_EFD_W);
1.411 djm 2828: }
2829: if (c->rfd == c->sock) {
1.415 djm 2830: fd_ready(c, p, pfd, npfd, c->sock,
2831: "sockr/r", POLLIN, SSH_CHAN_IO_SOCK_R);
2832: fd_ready(c, p, pfd, npfd, c->sock,
2833: "sockw/r", POLLOUT, SSH_CHAN_IO_SOCK_W);
1.411 djm 2834: }
1.415 djm 2835: dump_channel_poll(__func__, "rfd", c, p, pfd);
1.411 djm 2836: }
2837: /* wfd */
1.415 djm 2838: if (c->wfd != -1 && c->wfd != c->rfd &&
2839: (p = c->pfds[1]) != -1) {
2840: fd_ready(c, p, pfd, npfd, c->wfd,
2841: "wfd", POLLOUT, SSH_CHAN_IO_WFD);
2842: dump_channel_poll(__func__, "wfd", c, p, pfd);
1.411 djm 2843: }
2844: /* efd */
1.415 djm 2845: if (c->efd != -1 && c->efd != c->rfd &&
2846: (p = c->pfds[2]) != -1) {
2847: fd_ready(c, p, pfd, npfd, c->efd,
2848: "efdr", POLLIN, SSH_CHAN_IO_EFD_R);
2849: fd_ready(c, p, pfd, npfd, c->efd,
2850: "efdw", POLLOUT, SSH_CHAN_IO_EFD_W);
2851: dump_channel_poll(__func__, "efd", c, p, pfd);
1.411 djm 2852: }
2853: /* sock */
1.415 djm 2854: if (c->sock != -1 && c->sock != c->rfd &&
2855: (p = c->pfds[3]) != -1) {
2856: fd_ready(c, p, pfd, npfd, c->sock,
2857: "sockr", POLLIN, SSH_CHAN_IO_SOCK_R);
2858: fd_ready(c, p, pfd, npfd, c->sock,
2859: "sockw", POLLOUT, SSH_CHAN_IO_SOCK_W);
2860: dump_channel_poll(__func__, "sock", c, p, pfd);
1.411 djm 2861: }
1.410 djm 2862: }
2863: channel_handler(ssh, CHAN_POST, NULL);
1.367 djm 2864: }
2865:
2866: /*
2867: * Enqueue data for channels with open or draining c->input.
1.433 djm 2868: * Returns non-zero if a packet was enqueued.
1.367 djm 2869: */
1.433 djm 2870: static int
1.367 djm 2871: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2872: {
1.373 djm 2873: size_t len, plen;
2874: const u_char *pkt;
1.367 djm 2875: int r;
2876:
2877: if ((len = sshbuf_len(c->input)) == 0) {
2878: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2879: /*
2880: * input-buffer is empty and read-socket shutdown:
2881: * tell peer, that we will not send more data:
2882: * send IEOF.
2883: * hack for extended data: delay EOF if EFD still
2884: * in use.
2885: */
2886: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2887: debug2("channel %d: "
2888: "ibuf_empty delayed efd %d/(%zu)",
2889: c->self, c->efd, sshbuf_len(c->extended));
2890: else
2891: chan_ibuf_empty(ssh, c);
2892: }
1.433 djm 2893: return 0;
1.367 djm 2894: }
2895:
1.368 djm 2896: if (!c->have_remote_id)
1.403 djm 2897: fatal_f("channel %d: no remote id", c->self);
1.368 djm 2898:
1.367 djm 2899: if (c->datagram) {
2900: /* Check datagram will fit; drop if not */
1.373 djm 2901: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
1.403 djm 2902: fatal_fr(r, "channel %i: get datagram", c->self);
1.367 djm 2903: /*
2904: * XXX this does tail-drop on the datagram queue which is
2905: * usually suboptimal compared to head-drop. Better to have
2906: * backpressure at read time? (i.e. read + discard)
2907: */
1.373 djm 2908: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2909: debug("channel %d: datagram too big", c->self);
1.433 djm 2910: return 0;
1.367 djm 2911: }
2912: /* Enqueue it */
2913: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2914: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2915: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.403 djm 2916: (r = sshpkt_send(ssh)) != 0)
2917: fatal_fr(r, "channel %i: send datagram", c->self);
1.373 djm 2918: c->remote_window -= plen;
1.433 djm 2919: return 1;
1.367 djm 2920: }
2921:
2922: /* Enqueue packet for buffered data. */
2923: if (len > c->remote_window)
2924: len = c->remote_window;
2925: if (len > c->remote_maxpacket)
2926: len = c->remote_maxpacket;
2927: if (len == 0)
1.433 djm 2928: return 0;
1.367 djm 2929: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2930: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2931: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
1.403 djm 2932: (r = sshpkt_send(ssh)) != 0)
2933: fatal_fr(r, "channel %i: send data", c->self);
1.367 djm 2934: if ((r = sshbuf_consume(c->input, len)) != 0)
1.403 djm 2935: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2936: c->remote_window -= len;
1.433 djm 2937: return 1;
1.41 markus 2938: }
2939:
1.367 djm 2940: /*
2941: * Enqueue data for channels with open c->extended in read mode.
1.433 djm 2942: * Returns non-zero if a packet was enqueued.
1.367 djm 2943: */
1.433 djm 2944: static int
1.367 djm 2945: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2946: {
2947: size_t len;
2948: int r;
2949:
2950: if ((len = sshbuf_len(c->extended)) == 0)
1.433 djm 2951: return 0;
1.367 djm 2952:
2953: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2954: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2955: if (len > c->remote_window)
2956: len = c->remote_window;
2957: if (len > c->remote_maxpacket)
2958: len = c->remote_maxpacket;
2959: if (len == 0)
1.433 djm 2960: return 0;
1.368 djm 2961: if (!c->have_remote_id)
1.403 djm 2962: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2963: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2964: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2965: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2966: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
1.403 djm 2967: (r = sshpkt_send(ssh)) != 0)
2968: fatal_fr(r, "channel %i: data", c->self);
1.367 djm 2969: if ((r = sshbuf_consume(c->extended, len)) != 0)
1.403 djm 2970: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2971: c->remote_window -= len;
2972: debug2("channel %d: sent ext data %zu", c->self, len);
1.433 djm 2973: return 1;
1.367 djm 2974: }
1.121 markus 2975:
1.433 djm 2976: /*
2977: * If there is data to send to the connection, enqueue some of it now.
2978: * Returns non-zero if data was enqueued.
2979: */
2980: int
1.367 djm 2981: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2982: {
1.367 djm 2983: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2984: Channel *c;
1.367 djm 2985: u_int i;
1.433 djm 2986: int ret = 0;
1.1 deraadt 2987:
1.367 djm 2988: for (i = 0; i < sc->channels_alloc; i++) {
2989: c = sc->channels[i];
1.113 markus 2990: if (c == NULL)
2991: continue;
1.37 markus 2992:
1.121 markus 2993: /*
2994: * We are only interested in channels that can have buffered
2995: * incoming data.
2996: */
1.358 djm 2997: if (c->type != SSH_CHANNEL_OPEN)
2998: continue;
2999: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 3000: /* XXX is this true? */
1.367 djm 3001: debug3("channel %d: will not send data after close",
3002: c->self);
1.44 markus 3003: continue;
3004: }
1.25 markus 3005:
3006: /* Get the amount of buffered data for this channel. */
1.367 djm 3007: if (c->istate == CHAN_INPUT_OPEN ||
3008: c->istate == CHAN_INPUT_WAIT_DRAIN)
1.433 djm 3009: ret |= channel_output_poll_input_open(ssh, c);
1.44 markus 3010: /* Send extended data, i.e. stderr */
1.358 djm 3011: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 3012: c->extended_usage == CHAN_EXTENDED_READ)
1.433 djm 3013: ret |= channel_output_poll_extended_read(ssh, c);
1.25 markus 3014: }
1.433 djm 3015: return ret;
1.1 deraadt 3016: }
3017:
1.354 markus 3018: /* -- mux proxy support */
3019:
3020: /*
3021: * When multiplexing channel messages for mux clients we have to deal
3022: * with downstream messages from the mux client and upstream messages
3023: * from the ssh server:
3024: * 1) Handling downstream messages is straightforward and happens
3025: * in channel_proxy_downstream():
3026: * - We forward all messages (mostly) unmodified to the server.
3027: * - However, in order to route messages from upstream to the correct
3028: * downstream client, we have to replace the channel IDs used by the
3029: * mux clients with a unique channel ID because the mux clients might
3030: * use conflicting channel IDs.
3031: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
3032: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
3033: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
3034: * with the newly allocated channel ID.
3035: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 3036: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 3037: * is then translated back to the original mux client ID.
3038: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
3039: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
3040: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
3041: * downstream mux client are removed.
3042: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
3043: * requires more work, because they are not addressed to a specific
3044: * channel. E.g. client_request_forwarded_tcpip() needs to figure
3045: * out whether the request is addressed to the local client or a
3046: * specific downstream client based on the listen-address/port.
1.380 djm 3047: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 3048: * not supported as the matching session/channel cannot be identified
3049: * easily.
3050: */
3051:
3052: /*
3053: * receive packets from downstream mux clients:
3054: * channel callback fired on read from mux client, creates
3055: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
3056: * on channel creation.
3057: */
3058: int
1.367 djm 3059: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 3060: {
3061: Channel *c = NULL;
3062: struct sshbuf *original = NULL, *modified = NULL;
3063: const u_char *cp;
3064: char *ctype = NULL, *listen_host = NULL;
3065: u_char type;
3066: size_t have;
1.370 djm 3067: int ret = -1, r;
1.355 djm 3068: u_int id, remote_id, listen_port;
1.354 markus 3069:
1.367 djm 3070: /* sshbuf_dump(downstream->input, stderr); */
3071: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 3072: != 0) {
1.403 djm 3073: error_fr(r, "parse");
1.354 markus 3074: return -1;
3075: }
3076: if (have < 2) {
1.403 djm 3077: error_f("short message");
1.354 markus 3078: return -1;
3079: }
3080: type = cp[1];
3081: /* skip padlen + type */
3082: cp += 2;
3083: have -= 2;
3084: if (ssh_packet_log_type(type))
1.403 djm 3085: debug3_f("channel %u: down->up: type %u",
1.354 markus 3086: downstream->self, type);
3087:
3088: switch (type) {
3089: case SSH2_MSG_CHANNEL_OPEN:
3090: if ((original = sshbuf_from(cp, have)) == NULL ||
3091: (modified = sshbuf_new()) == NULL) {
1.403 djm 3092: error_f("alloc");
1.354 markus 3093: goto out;
3094: }
3095: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
3096: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 3097: error_fr(r, "parse");
1.354 markus 3098: goto out;
3099: }
1.424 djm 3100: c = channel_new(ssh, "mux-proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 3101: -1, -1, -1, 0, 0, 0, ctype, 1);
1.354 markus 3102: c->mux_ctx = downstream; /* point to mux client */
3103: c->mux_downstream_id = id; /* original downstream id */
3104: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
3105: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
3106: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 3107: error_fr(r, "compose");
1.367 djm 3108: channel_free(ssh, c);
1.354 markus 3109: goto out;
3110: }
3111: break;
3112: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3113: /*
3114: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
3115: * need to parse 'remote_id' instead of 'ctype'.
3116: */
3117: if ((original = sshbuf_from(cp, have)) == NULL ||
3118: (modified = sshbuf_new()) == NULL) {
1.403 djm 3119: error_f("alloc");
1.354 markus 3120: goto out;
3121: }
3122: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
3123: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 3124: error_fr(r, "parse");
1.354 markus 3125: goto out;
3126: }
1.424 djm 3127: c = channel_new(ssh, "mux-proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 3128: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
1.354 markus 3129: c->mux_ctx = downstream; /* point to mux client */
3130: c->mux_downstream_id = id;
3131: c->remote_id = remote_id;
1.368 djm 3132: c->have_remote_id = 1;
1.354 markus 3133: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
3134: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
3135: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 3136: error_fr(r, "compose");
1.367 djm 3137: channel_free(ssh, c);
1.354 markus 3138: goto out;
3139: }
3140: break;
3141: case SSH2_MSG_GLOBAL_REQUEST:
3142: if ((original = sshbuf_from(cp, have)) == NULL) {
1.403 djm 3143: error_f("alloc");
1.354 markus 3144: goto out;
3145: }
3146: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
1.403 djm 3147: error_fr(r, "parse");
1.354 markus 3148: goto out;
3149: }
3150: if (strcmp(ctype, "tcpip-forward") != 0) {
1.403 djm 3151: error_f("unsupported request %s", ctype);
1.354 markus 3152: goto out;
3153: }
3154: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
3155: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
3156: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
1.403 djm 3157: error_fr(r, "parse");
1.354 markus 3158: goto out;
3159: }
1.355 djm 3160: if (listen_port > 65535) {
1.403 djm 3161: error_f("tcpip-forward for %s: bad port %u",
3162: listen_host, listen_port);
1.355 djm 3163: goto out;
3164: }
1.354 markus 3165: /* Record that connection to this host/port is permitted. */
1.381 djm 3166: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 3167: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 3168: listen_host = NULL;
3169: break;
3170: case SSH2_MSG_CHANNEL_CLOSE:
3171: if (have < 4)
3172: break;
3173: remote_id = PEEK_U32(cp);
1.367 djm 3174: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 3175: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 3176: channel_free(ssh, c);
1.354 markus 3177: else
3178: c->flags |= CHAN_CLOSE_SENT;
3179: }
3180: break;
3181: }
3182: if (modified) {
3183: if ((r = sshpkt_start(ssh, type)) != 0 ||
3184: (r = sshpkt_putb(ssh, modified)) != 0 ||
3185: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3186: error_fr(r, "send");
1.354 markus 3187: goto out;
3188: }
3189: } else {
3190: if ((r = sshpkt_start(ssh, type)) != 0 ||
3191: (r = sshpkt_put(ssh, cp, have)) != 0 ||
3192: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3193: error_fr(r, "send");
1.354 markus 3194: goto out;
3195: }
3196: }
3197: ret = 0;
3198: out:
3199: free(ctype);
3200: free(listen_host);
3201: sshbuf_free(original);
3202: sshbuf_free(modified);
3203: return ret;
3204: }
3205:
3206: /*
3207: * receive packets from upstream server and de-multiplex packets
3208: * to correct downstream:
3209: * implemented as a helper for channel input handlers,
3210: * replaces local (proxy) channel ID with downstream channel ID.
3211: */
3212: int
1.363 markus 3213: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 3214: {
3215: struct sshbuf *b = NULL;
3216: Channel *downstream;
3217: const u_char *cp = NULL;
3218: size_t len;
3219: int r;
3220:
3221: /*
3222: * When receiving packets from the peer we need to check whether we
3223: * need to forward the packets to the mux client. In this case we
1.380 djm 3224: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 3225: * so we can cleanup the channel.
3226: */
3227: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
3228: return 0;
3229: if ((downstream = c->mux_ctx) == NULL)
3230: return 0;
3231: switch (type) {
3232: case SSH2_MSG_CHANNEL_CLOSE:
3233: case SSH2_MSG_CHANNEL_DATA:
3234: case SSH2_MSG_CHANNEL_EOF:
3235: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
3236: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3237: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
3238: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
3239: case SSH2_MSG_CHANNEL_SUCCESS:
3240: case SSH2_MSG_CHANNEL_FAILURE:
3241: case SSH2_MSG_CHANNEL_REQUEST:
3242: break;
3243: default:
1.403 djm 3244: debug2_f("channel %u: unsupported type %u", c->self, type);
1.354 markus 3245: return 0;
3246: }
3247: if ((b = sshbuf_new()) == NULL) {
1.403 djm 3248: error_f("alloc reply");
1.354 markus 3249: goto out;
3250: }
3251: /* get remaining payload (after id) */
3252: cp = sshpkt_ptr(ssh, &len);
3253: if (cp == NULL) {
1.403 djm 3254: error_f("no packet");
1.354 markus 3255: goto out;
3256: }
3257: /* translate id and send to muxclient */
3258: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
3259: (r = sshbuf_put_u8(b, type)) != 0 ||
3260: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
3261: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 3262: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.403 djm 3263: error_fr(r, "compose muxclient");
1.354 markus 3264: goto out;
3265: }
3266: /* sshbuf_dump(b, stderr); */
3267: if (ssh_packet_log_type(type))
1.403 djm 3268: debug3_f("channel %u: up->down: type %u", c->self, type);
1.354 markus 3269: out:
3270: /* update state */
3271: switch (type) {
3272: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3273: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 3274: if (cp && len > 4) {
1.354 markus 3275: c->remote_id = PEEK_U32(cp);
1.368 djm 3276: c->have_remote_id = 1;
3277: }
1.354 markus 3278: break;
3279: case SSH2_MSG_CHANNEL_CLOSE:
3280: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 3281: channel_free(ssh, c);
1.354 markus 3282: else
3283: c->flags |= CHAN_CLOSE_RCVD;
3284: break;
3285: }
3286: sshbuf_free(b);
3287: return 1;
3288: }
1.121 markus 3289:
3290: /* -- protocol input */
1.249 djm 3291:
1.367 djm 3292: /* Parse a channel ID from the current packet */
3293: static int
3294: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
3295: {
3296: u_int32_t id;
3297: int r;
3298:
3299: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
1.403 djm 3300: error_r(r, "%s: parse id", where);
1.367 djm 3301: ssh_packet_disconnect(ssh, "Invalid %s message", what);
3302: }
3303: if (id > INT_MAX) {
1.403 djm 3304: error_r(r, "%s: bad channel id %u", where, id);
1.367 djm 3305: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
3306: }
3307: return (int)id;
3308: }
3309:
3310: /* Lookup a channel from an ID in the current packet */
3311: static Channel *
3312: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
3313: {
3314: int id = channel_parse_id(ssh, where, what);
3315: Channel *c;
3316:
3317: if ((c = channel_lookup(ssh, id)) == NULL) {
3318: ssh_packet_disconnect(ssh,
3319: "%s packet referred to nonexistent channel %d", what, id);
3320: }
3321: return c;
3322: }
3323:
1.339 markus 3324: int
1.363 markus 3325: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3326: {
1.332 djm 3327: const u_char *data;
1.367 djm 3328: size_t data_len, win_len;
3329: Channel *c = channel_from_packet_id(ssh, __func__, "data");
3330: int r;
1.25 markus 3331:
1.363 markus 3332: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3333: return 0;
1.25 markus 3334:
3335: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 3336: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 3337: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
3338: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 3339: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 3340: return 0;
1.37 markus 3341:
1.25 markus 3342: /* Get the data. */
1.389 djm 3343: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3344: (r = sshpkt_get_end(ssh)) != 0)
1.403 djm 3345: fatal_fr(r, "channel %i: get data", c->self);
1.367 djm 3346:
1.309 djm 3347: win_len = data_len;
3348: if (c->datagram)
3349: win_len += 4; /* string length header */
1.200 markus 3350:
3351: /*
1.367 djm 3352: * The sending side reduces its window as it sends data, so we
3353: * must 'fake' consumption of the data in order to ensure that window
3354: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 3355: */
1.358 djm 3356: if (c->ostate != CHAN_OUTPUT_OPEN) {
3357: c->local_window -= win_len;
3358: c->local_consumed += win_len;
1.339 markus 3359: return 0;
1.200 markus 3360: }
1.41 markus 3361:
1.358 djm 3362: if (win_len > c->local_maxpacket) {
1.367 djm 3363: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 3364: c->self, win_len, c->local_maxpacket);
1.367 djm 3365: return 0;
1.358 djm 3366: }
3367: if (win_len > c->local_window) {
1.435 ! djm 3368: c->local_window_exceeded += win_len - c->local_window;
! 3369: logit("channel %d: rcvd too much data %zu, win %u/%u "
! 3370: "(excess %u)", c->self, win_len, c->local_window,
! 3371: c->local_window_max, c->local_window_exceeded);
! 3372: c->local_window = 0;
! 3373: /* Allow 10% grace before bringing the hammer down */
! 3374: if (c->local_window_exceeded > (c->local_window_max / 10)) {
! 3375: ssh_packet_disconnect(ssh, "channel %d: peer ignored "
! 3376: "channel window", c->self);
! 3377: }
! 3378: } else {
! 3379: c->local_window -= win_len;
! 3380: c->local_window_exceeded = 0;
1.44 markus 3381: }
1.358 djm 3382:
1.367 djm 3383: if (c->datagram) {
3384: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
1.403 djm 3385: fatal_fr(r, "channel %i: append datagram", c->self);
1.367 djm 3386: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
1.403 djm 3387: fatal_fr(r, "channel %i: append data", c->self);
1.367 djm 3388:
1.339 markus 3389: return 0;
1.1 deraadt 3390: }
1.121 markus 3391:
1.339 markus 3392: int
1.363 markus 3393: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 3394: {
1.367 djm 3395: const u_char *data;
3396: size_t data_len;
3397: u_int32_t tcode;
3398: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
3399: int r;
1.44 markus 3400:
1.363 markus 3401: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3402: return 0;
1.44 markus 3403: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 3404: logit("channel %d: ext data for non open", c->self);
1.339 markus 3405: return 0;
1.172 markus 3406: }
3407: if (c->flags & CHAN_EOF_RCVD) {
1.404 djm 3408: if (ssh->compat & SSH_BUG_EXTEOF)
1.367 djm 3409: debug("channel %d: accepting ext data after eof",
3410: c->self);
1.172 markus 3411: else
1.367 djm 3412: ssh_packet_disconnect(ssh, "Received extended_data "
3413: "after EOF on channel %d.", c->self);
3414: }
3415:
3416: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
1.403 djm 3417: error_fr(r, "parse tcode");
1.367 djm 3418: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3419: }
3420: if (c->efd == -1 ||
3421: c->extended_usage != CHAN_EXTENDED_WRITE ||
3422: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3423: logit("channel %d: bad ext data", c->self);
1.339 markus 3424: return 0;
1.44 markus 3425: }
1.389 djm 3426: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3427: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3428: error_fr(r, "parse data");
1.367 djm 3429: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3430: }
3431:
1.44 markus 3432: if (data_len > c->local_window) {
1.367 djm 3433: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3434: c->self, data_len, c->local_window);
1.339 markus 3435: return 0;
1.44 markus 3436: }
1.367 djm 3437: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3438: /* XXX sshpkt_getb? */
3439: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
1.403 djm 3440: error_fr(r, "append");
1.44 markus 3441: c->local_window -= data_len;
1.339 markus 3442: return 0;
1.44 markus 3443: }
3444:
1.339 markus 3445: int
1.363 markus 3446: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3447: {
1.367 djm 3448: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3449: int r;
1.367 djm 3450:
1.389 djm 3451: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3452: error_fr(r, "parse data");
1.389 djm 3453: ssh_packet_disconnect(ssh, "Invalid ieof message");
3454: }
1.41 markus 3455:
1.363 markus 3456: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3457: return 0;
1.367 djm 3458: chan_rcvd_ieof(ssh, c);
1.133 markus 3459:
3460: /* XXX force input close */
1.156 markus 3461: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3462: debug("channel %d: FORCE input drain", c->self);
3463: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3464: if (sshbuf_len(c->input) == 0)
3465: chan_ibuf_empty(ssh, c);
1.133 markus 3466: }
1.339 markus 3467: return 0;
1.41 markus 3468: }
1.1 deraadt 3469:
1.339 markus 3470: int
1.363 markus 3471: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3472: {
1.367 djm 3473: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3474: int r;
1.151 markus 3475:
1.363 markus 3476: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3477: return 0;
1.389 djm 3478: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3479: error_fr(r, "parse data");
1.389 djm 3480: ssh_packet_disconnect(ssh, "Invalid oclose message");
3481: }
1.367 djm 3482: chan_rcvd_oclose(ssh, c);
1.339 markus 3483: return 0;
1.1 deraadt 3484: }
3485:
1.339 markus 3486: int
1.363 markus 3487: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3488: {
1.367 djm 3489: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3490: u_int32_t remote_window, remote_maxpacket;
3491: int r;
1.25 markus 3492:
1.363 markus 3493: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3494: return 0;
3495: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3496: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3497: "non-opening channel %d.", c->self);
3498: /*
3499: * Record the remote channel number and mark that the channel
3500: * is now open.
3501: */
1.368 djm 3502: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3503: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3504: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3505: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3506: error_fr(r, "window/maxpacket");
1.389 djm 3507: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3508: }
3509:
1.368 djm 3510: c->have_remote_id = 1;
1.367 djm 3511: c->remote_window = remote_window;
3512: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3513: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3514: if (c->open_confirm) {
1.403 djm 3515: debug2_f("channel %d: callback start", c->self);
1.367 djm 3516: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
1.403 djm 3517: debug2_f("channel %d: callback done", c->self);
1.44 markus 3518: }
1.426 djm 3519: c->lastused = monotime();
1.358 djm 3520: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3521: c->remote_window, c->remote_maxpacket);
1.339 markus 3522: return 0;
1.1 deraadt 3523: }
3524:
1.127 itojun 3525: static char *
1.114 markus 3526: reason2txt(int reason)
3527: {
1.143 deraadt 3528: switch (reason) {
1.114 markus 3529: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3530: return "administratively prohibited";
3531: case SSH2_OPEN_CONNECT_FAILED:
3532: return "connect failed";
3533: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3534: return "unknown channel type";
3535: case SSH2_OPEN_RESOURCE_SHORTAGE:
3536: return "resource shortage";
3537: }
1.117 stevesk 3538: return "unknown reason";
1.114 markus 3539: }
3540:
1.339 markus 3541: int
1.363 markus 3542: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3543: {
1.367 djm 3544: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3545: u_int32_t reason;
3546: char *msg = NULL;
3547: int r;
1.25 markus 3548:
1.363 markus 3549: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3550: return 0;
3551: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3552: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3553: "non-opening channel %d.", c->self);
3554: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
1.403 djm 3555: error_fr(r, "parse reason");
1.389 djm 3556: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3557: }
1.378 djm 3558: /* skip language */
3559: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3560: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3561: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3562: error_fr(r, "parse msg/lang");
1.389 djm 3563: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3564: }
1.367 djm 3565: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3566: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3567: free(msg);
3568: if (c->open_confirm) {
1.403 djm 3569: debug2_f("channel %d: callback start", c->self);
1.367 djm 3570: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
1.403 djm 3571: debug2_f("channel %d: callback done", c->self);
1.44 markus 3572: }
1.291 djm 3573: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3574: chan_mark_dead(ssh, c);
1.339 markus 3575: return 0;
1.44 markus 3576: }
3577:
1.339 markus 3578: int
1.363 markus 3579: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3580: {
1.367 djm 3581: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3582: Channel *c;
1.367 djm 3583: u_int32_t adjust;
3584: u_int new_rwin;
3585: int r;
1.1 deraadt 3586:
1.367 djm 3587: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3588: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3589: return 0;
1.372 markus 3590: }
1.367 djm 3591:
1.363 markus 3592: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3593: return 0;
1.389 djm 3594: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3595: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3596: error_fr(r, "parse adjust");
1.389 djm 3597: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3598: }
3599: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3600: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3601: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3602: c->self, adjust, c->remote_window);
3603: }
3604: c->remote_window = new_rwin;
1.339 markus 3605: return 0;
1.121 markus 3606: }
1.1 deraadt 3607:
1.339 markus 3608: int
1.363 markus 3609: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3610: {
1.367 djm 3611: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3612: Channel *c;
3613: struct channel_confirm *cc;
3614:
3615: /* Reset keepalive timeout */
1.389 djm 3616: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3617:
1.403 djm 3618: debug2_f("type %d id %d", type, id);
1.275 djm 3619:
1.367 djm 3620: if ((c = channel_lookup(ssh, id)) == NULL) {
1.403 djm 3621: logit_f("%d: unknown", id);
1.339 markus 3622: return 0;
1.367 djm 3623: }
1.363 markus 3624: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3625: return 0;
1.394 dtucker 3626: if (sshpkt_get_end(ssh) != 0)
1.389 djm 3627: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3628: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3629: return 0;
1.367 djm 3630: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3631: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 3632: freezero(cc, sizeof(*cc));
1.339 markus 3633: return 0;
1.275 djm 3634: }
1.121 markus 3635:
3636: /* -- tcp forwarding */
1.135 markus 3637:
3638: void
1.367 djm 3639: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3640: {
1.367 djm 3641: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3642: }
1.121 markus 3643:
1.312 djm 3644:
3645: /*
3646: * Determine whether or not a port forward listens to loopback, the
3647: * specified address or wildcard. On the client, a specified bind
3648: * address will always override gateway_ports. On the server, a
3649: * gateway_ports of 1 (``yes'') will override the client's specification
3650: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3651: * will bind to whatever address the client asked for.
3652: *
3653: * Special-case listen_addrs are:
3654: *
3655: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3656: * "" (empty string), "*" -> wildcard v4/v6
3657: * "localhost" -> loopback v4/v6
1.334 djm 3658: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3659: */
3660: static const char *
1.389 djm 3661: channel_fwd_bind_addr(struct ssh *ssh, const char *listen_addr, int *wildcardp,
1.336 millert 3662: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3663: {
3664: const char *addr = NULL;
3665: int wildcard = 0;
3666:
3667: if (listen_addr == NULL) {
3668: /* No address specified: default to gateway_ports setting */
1.336 millert 3669: if (fwd_opts->gateway_ports)
1.312 djm 3670: wildcard = 1;
1.336 millert 3671: } else if (fwd_opts->gateway_ports || is_client) {
1.404 djm 3672: if (((ssh->compat & SSH_OLD_FORWARD_ADDR) &&
1.312 djm 3673: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3674: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3675: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3676: wildcard = 1;
1.326 djm 3677: /*
3678: * Notify client if they requested a specific listen
3679: * address and it was overridden.
3680: */
3681: if (*listen_addr != '\0' &&
3682: strcmp(listen_addr, "0.0.0.0") != 0 &&
3683: strcmp(listen_addr, "*") != 0) {
1.389 djm 3684: ssh_packet_send_debug(ssh,
3685: "Forwarding listen address "
1.326 djm 3686: "\"%s\" overridden by server "
3687: "GatewayPorts", listen_addr);
3688: }
1.334 djm 3689: } else if (strcmp(listen_addr, "localhost") != 0 ||
3690: strcmp(listen_addr, "127.0.0.1") == 0 ||
3691: strcmp(listen_addr, "::1") == 0) {
1.395 djm 3692: /*
3693: * Accept explicit localhost address when
3694: * GatewayPorts=yes. The "localhost" hostname is
3695: * deliberately skipped here so it will listen on all
3696: * available local address families.
3697: */
1.334 djm 3698: addr = listen_addr;
1.326 djm 3699: }
1.334 djm 3700: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3701: strcmp(listen_addr, "::1") == 0) {
3702: /*
3703: * If a specific IPv4/IPv6 localhost address has been
3704: * requested then accept it even if gateway_ports is in
3705: * effect. This allows the client to prefer IPv4 or IPv6.
3706: */
3707: addr = listen_addr;
1.312 djm 3708: }
3709: if (wildcardp != NULL)
3710: *wildcardp = wildcard;
3711: return addr;
3712: }
3713:
1.160 markus 3714: static int
1.367 djm 3715: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3716: struct Forward *fwd, int *allocated_listen_port,
3717: struct ForwardOptions *fwd_opts)
1.25 markus 3718: {
1.113 markus 3719: Channel *c;
1.226 djm 3720: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3721: struct addrinfo hints, *ai, *aitop;
1.212 djm 3722: const char *host, *addr;
1.35 markus 3723: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3724: in_port_t *lport_p;
1.25 markus 3725:
1.212 djm 3726: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3727:
1.344 millert 3728: if (is_client && fwd->connect_path != NULL) {
3729: host = fwd->connect_path;
3730: } else {
3731: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3732: fwd->listen_host : fwd->connect_host;
3733: if (host == NULL) {
3734: error("No forward host name.");
3735: return 0;
3736: }
3737: if (strlen(host) >= NI_MAXHOST) {
3738: error("Forward host name too long.");
3739: return 0;
3740: }
1.87 markus 3741: }
1.25 markus 3742:
1.312 djm 3743: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3744: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3745: is_client, fwd_opts);
1.403 djm 3746: debug3_f("type %d wildcard %d addr %s", type, wildcard,
3747: (addr == NULL) ? "NULL" : addr);
1.212 djm 3748:
3749: /*
1.35 markus 3750: * getaddrinfo returns a loopback address if the hostname is
3751: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3752: */
1.35 markus 3753: memset(&hints, 0, sizeof(hints));
1.367 djm 3754: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3755: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3756: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3757: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3758: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3759: if (addr == NULL) {
3760: /* This really shouldn't happen */
1.389 djm 3761: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3762: ssh_gai_strerror(r));
1.212 djm 3763: } else {
1.403 djm 3764: error_f("getaddrinfo(%.64s): %s", addr,
1.271 dtucker 3765: ssh_gai_strerror(r));
1.212 djm 3766: }
1.218 markus 3767: return 0;
1.212 djm 3768: }
1.295 djm 3769: if (allocated_listen_port != NULL)
3770: *allocated_listen_port = 0;
1.35 markus 3771: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3772: switch (ai->ai_family) {
3773: case AF_INET:
3774: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3775: sin_port;
3776: break;
3777: case AF_INET6:
3778: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3779: sin6_port;
3780: break;
3781: default:
1.35 markus 3782: continue;
1.295 djm 3783: }
3784: /*
3785: * If allocating a port for -R forwards, then use the
3786: * same port for all address families.
3787: */
1.367 djm 3788: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3789: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3790: *allocated_listen_port > 0)
1.295 djm 3791: *lport_p = htons(*allocated_listen_port);
3792:
1.35 markus 3793: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3794: strport, sizeof(strport),
3795: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.403 djm 3796: error_f("getnameinfo failed");
1.35 markus 3797: continue;
3798: }
3799: /* Create a port to listen for the host. */
1.300 dtucker 3800: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 3801: if (sock == -1) {
1.35 markus 3802: /* this is no error since kernel may not support ipv6 */
1.377 djm 3803: verbose("socket [%s]:%s: %.100s", ntop, strport,
3804: strerror(errno));
1.35 markus 3805: continue;
3806: }
1.226 djm 3807:
1.376 djm 3808: set_reuseaddr(sock);
1.182 stevesk 3809:
1.295 djm 3810: debug("Local forwarding listening on %s port %s.",
3811: ntop, strport);
1.35 markus 3812:
3813: /* Bind the socket to the address. */
1.393 deraadt 3814: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3815: /*
3816: * address can be in if use ipv6 address is
3817: * already bound
3818: */
1.377 djm 3819: verbose("bind [%s]:%s: %.100s",
3820: ntop, strport, strerror(errno));
1.35 markus 3821: close(sock);
3822: continue;
3823: }
3824: /* Start listening for connections on the socket. */
1.393 deraadt 3825: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3826: error("listen [%s]:%s: %.100s", ntop, strport,
3827: strerror(errno));
1.35 markus 3828: close(sock);
3829: continue;
3830: }
1.295 djm 3831:
3832: /*
1.336 millert 3833: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3834: * record what we got.
3835: */
1.367 djm 3836: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3837: fwd->listen_port == 0 &&
1.295 djm 3838: allocated_listen_port != NULL &&
3839: *allocated_listen_port == 0) {
1.350 djm 3840: *allocated_listen_port = get_local_port(sock);
1.295 djm 3841: debug("Allocated listen port %d",
3842: *allocated_listen_port);
3843: }
3844:
1.35 markus 3845: /* Allocate a channel number for the socket. */
1.424 djm 3846: c = channel_new(ssh, "port-listener", type, sock, sock, -1,
1.51 markus 3847: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3848: 0, "port listener", 1);
1.293 djm 3849: c->path = xstrdup(host);
1.336 millert 3850: c->host_port = fwd->connect_port;
1.312 djm 3851: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3852: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.404 djm 3853: !(ssh->compat & SSH_BUG_DYNAMIC_RPORT))
1.315 markus 3854: c->listening_port = *allocated_listen_port;
3855: else
1.336 millert 3856: c->listening_port = fwd->listen_port;
1.35 markus 3857: success = 1;
3858: }
3859: if (success == 0)
1.403 djm 3860: error_f("cannot listen to port: %d", fwd->listen_port);
1.35 markus 3861: freeaddrinfo(aitop);
1.87 markus 3862: return success;
1.25 markus 3863: }
1.1 deraadt 3864:
1.336 millert 3865: static int
1.367 djm 3866: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3867: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3868: {
3869: struct sockaddr_un sunaddr;
3870: const char *path;
3871: Channel *c;
3872: int port, sock;
3873: mode_t omask;
3874:
3875: switch (type) {
3876: case SSH_CHANNEL_UNIX_LISTENER:
3877: if (fwd->connect_path != NULL) {
3878: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3879: error("Local connecting path too long: %s",
3880: fwd->connect_path);
3881: return 0;
3882: }
3883: path = fwd->connect_path;
3884: port = PORT_STREAMLOCAL;
3885: } else {
3886: if (fwd->connect_host == NULL) {
3887: error("No forward host name.");
3888: return 0;
3889: }
3890: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3891: error("Forward host name too long.");
3892: return 0;
3893: }
3894: path = fwd->connect_host;
3895: port = fwd->connect_port;
3896: }
3897: break;
3898: case SSH_CHANNEL_RUNIX_LISTENER:
3899: path = fwd->listen_path;
3900: port = PORT_STREAMLOCAL;
3901: break;
3902: default:
1.403 djm 3903: error_f("unexpected channel type %d", type);
1.336 millert 3904: return 0;
3905: }
3906:
3907: if (fwd->listen_path == NULL) {
3908: error("No forward path name.");
3909: return 0;
3910: }
3911: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3912: error("Local listening path too long: %s", fwd->listen_path);
3913: return 0;
3914: }
3915:
1.403 djm 3916: debug3_f("type %d path %s", type, fwd->listen_path);
1.336 millert 3917:
3918: /* Start a Unix domain listener. */
3919: omask = umask(fwd_opts->streamlocal_bind_mask);
3920: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3921: fwd_opts->streamlocal_bind_unlink);
3922: umask(omask);
3923: if (sock < 0)
3924: return 0;
3925:
3926: debug("Local forwarding listening on path %s.", fwd->listen_path);
3927:
3928: /* Allocate a channel number for the socket. */
1.424 djm 3929: c = channel_new(ssh, "unix-listener", type, sock, sock, -1,
1.336 millert 3930: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3931: 0, "unix listener", 1);
3932: c->path = xstrdup(path);
3933: c->host_port = port;
3934: c->listening_port = PORT_STREAMLOCAL;
3935: c->listening_addr = xstrdup(fwd->listen_path);
3936: return 1;
3937: }
3938:
3939: static int
1.367 djm 3940: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3941: const char *host, u_short port)
1.202 djm 3942: {
1.209 avsm 3943: u_int i;
3944: int found = 0;
1.202 djm 3945:
1.367 djm 3946: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3947: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3948: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3949: continue;
3950: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
1.403 djm 3951: debug2_f("close channel %d", i);
1.367 djm 3952: channel_free(ssh, c);
1.312 djm 3953: found = 1;
3954: }
3955: }
3956:
1.367 djm 3957: return found;
1.312 djm 3958: }
3959:
1.336 millert 3960: static int
1.367 djm 3961: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3962: {
3963: u_int i;
3964: int found = 0;
3965:
1.367 djm 3966: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3967: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3968: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3969: continue;
3970: if (c->path == NULL)
3971: continue;
3972: if (strcmp(c->path, path) == 0) {
1.403 djm 3973: debug2_f("close channel %d", i);
1.367 djm 3974: channel_free(ssh, c);
1.336 millert 3975: found = 1;
3976: }
3977: }
3978:
1.367 djm 3979: return found;
1.336 millert 3980: }
3981:
1.312 djm 3982: int
1.367 djm 3983: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3984: {
1.367 djm 3985: if (fwd->listen_path != NULL) {
3986: return channel_cancel_rport_listener_streamlocal(ssh,
3987: fwd->listen_path);
3988: } else {
3989: return channel_cancel_rport_listener_tcpip(ssh,
3990: fwd->listen_host, fwd->listen_port);
3991: }
1.336 millert 3992: }
3993:
3994: static int
1.367 djm 3995: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3996: const char *lhost, u_short lport, int cport,
3997: struct ForwardOptions *fwd_opts)
1.312 djm 3998: {
3999: u_int i;
4000: int found = 0;
1.389 djm 4001: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 4002:
1.367 djm 4003: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
4004: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 4005: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
4006: continue;
1.313 markus 4007: if (c->listening_port != lport)
1.312 djm 4008: continue;
1.313 markus 4009: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
4010: /* skip dynamic forwardings */
4011: if (c->host_port == 0)
4012: continue;
4013: } else {
4014: if (c->host_port != cport)
4015: continue;
4016: }
1.312 djm 4017: if ((c->listening_addr == NULL && addr != NULL) ||
4018: (c->listening_addr != NULL && addr == NULL))
4019: continue;
4020: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.403 djm 4021: debug2_f("close channel %d", i);
1.367 djm 4022: channel_free(ssh, c);
1.202 djm 4023: found = 1;
4024: }
4025: }
4026:
1.367 djm 4027: return found;
1.202 djm 4028: }
4029:
1.336 millert 4030: static int
1.367 djm 4031: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 4032: {
4033: u_int i;
4034: int found = 0;
4035:
4036: if (path == NULL) {
1.403 djm 4037: error_f("no path specified.");
1.336 millert 4038: return 0;
4039: }
4040:
1.367 djm 4041: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
4042: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 4043: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
4044: continue;
4045: if (c->listening_addr == NULL)
4046: continue;
4047: if (strcmp(c->listening_addr, path) == 0) {
1.403 djm 4048: debug2_f("close channel %d", i);
1.367 djm 4049: channel_free(ssh, c);
1.336 millert 4050: found = 1;
4051: }
4052: }
4053:
1.367 djm 4054: return found;
1.336 millert 4055: }
4056:
4057: int
1.367 djm 4058: channel_cancel_lport_listener(struct ssh *ssh,
4059: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 4060: {
1.367 djm 4061: if (fwd->listen_path != NULL) {
4062: return channel_cancel_lport_listener_streamlocal(ssh,
4063: fwd->listen_path);
4064: } else {
4065: return channel_cancel_lport_listener_tcpip(ssh,
4066: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
4067: }
1.336 millert 4068: }
4069:
1.362 markus 4070: /* protocol local port fwd, used by ssh */
1.160 markus 4071: int
1.367 djm 4072: channel_setup_local_fwd_listener(struct ssh *ssh,
4073: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 4074: {
1.336 millert 4075: if (fwd->listen_path != NULL) {
1.367 djm 4076: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 4077: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
4078: } else {
1.367 djm 4079: return channel_setup_fwd_listener_tcpip(ssh,
4080: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 4081: }
1.160 markus 4082: }
4083:
1.381 djm 4084: /* Matches a remote forwarding permission against a requested forwarding */
4085: static int
4086: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
4087: {
4088: int ret;
4089: char *lhost;
4090:
4091: /* XXX add ACLs for streamlocal */
4092: if (fwd->listen_path != NULL)
4093: return 1;
4094:
4095: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
4096: return 0;
4097:
4098: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
4099: allowed_open->listen_port != fwd->listen_port)
4100: return 0;
4101:
4102: /* Match hostnames case-insensitively */
4103: lhost = xstrdup(fwd->listen_host);
4104: lowercase(lhost);
4105: ret = match_pattern(lhost, allowed_open->listen_host);
4106: free(lhost);
4107:
4108: return ret;
4109: }
4110:
4111: /* Checks whether a requested remote forwarding is permitted */
4112: static int
4113: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
4114: {
4115: struct ssh_channels *sc = ssh->chanctxt;
4116: struct permission_set *pset = &sc->remote_perms;
4117: u_int i, permit, permit_adm = 1;
4118: struct permission *perm;
4119:
4120: /* XXX apply GatewayPorts override before checking? */
4121:
4122: permit = pset->all_permitted;
4123: if (!permit) {
4124: for (i = 0; i < pset->num_permitted_user; i++) {
4125: perm = &pset->permitted_user[i];
4126: if (remote_open_match(perm, fwd)) {
4127: permit = 1;
4128: break;
4129: }
4130: }
4131: }
4132:
4133: if (pset->num_permitted_admin > 0) {
4134: permit_adm = 0;
4135: for (i = 0; i < pset->num_permitted_admin; i++) {
4136: perm = &pset->permitted_admin[i];
4137: if (remote_open_match(perm, fwd)) {
4138: permit_adm = 1;
4139: break;
4140: }
4141: }
4142: }
4143:
4144: return permit && permit_adm;
4145: }
4146:
1.160 markus 4147: /* protocol v2 remote port fwd, used by sshd */
4148: int
1.367 djm 4149: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 4150: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 4151: {
1.381 djm 4152: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 4153: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 4154: if (fwd->listen_path != NULL)
4155: /* XXX always allowed, see remote_open_match() */
4156: logit("Received request from %.100s port %d to "
4157: "remote forward to path \"%.100s\", "
4158: "but the request was denied.",
4159: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
4160: fwd->listen_path);
4161: else if(fwd->listen_host != NULL)
4162: logit("Received request from %.100s port %d to "
4163: "remote forward to host %.100s port %d, "
4164: "but the request was denied.",
4165: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
4166: fwd->listen_host, fwd->listen_port );
4167: else
4168: logit("Received request from %.100s port %d to remote "
4169: "forward, but the request was denied.",
4170: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 4171: return 0;
4172: }
1.336 millert 4173: if (fwd->listen_path != NULL) {
1.367 djm 4174: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 4175: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
4176: } else {
1.367 djm 4177: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 4178: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
4179: fwd_opts);
4180: }
1.160 markus 4181: }
4182:
1.27 markus 4183: /*
1.312 djm 4184: * Translate the requested rfwd listen host to something usable for
4185: * this server.
4186: */
4187: static const char *
4188: channel_rfwd_bind_host(const char *listen_host)
4189: {
4190: if (listen_host == NULL) {
1.378 djm 4191: return "localhost";
1.312 djm 4192: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 4193: return "";
1.312 djm 4194: } else
4195: return listen_host;
4196: }
4197:
4198: /*
1.27 markus 4199: * Initiate forwarding of connections to port "port" on remote host through
4200: * the secure channel to host:port from local side.
1.315 markus 4201: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 4202: * channel_update_permission().
1.27 markus 4203: */
1.253 markus 4204: int
1.367 djm 4205: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 4206: {
1.367 djm 4207: int r, success = 0, idx = -1;
1.421 mbuhl 4208: const char *host_to_connect, *listen_host, *listen_path;
1.367 djm 4209: int port_to_connect, listen_port;
1.73 markus 4210:
1.25 markus 4211: /* Send the forward request to the remote side. */
1.358 djm 4212: if (fwd->listen_path != NULL) {
1.367 djm 4213: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4214: (r = sshpkt_put_cstring(ssh,
4215: "streamlocal-forward@openssh.com")) != 0 ||
4216: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4217: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
4218: (r = sshpkt_send(ssh)) != 0 ||
4219: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4220: fatal_fr(r, "request streamlocal");
1.336 millert 4221: } else {
1.367 djm 4222: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4223: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
4224: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4225: (r = sshpkt_put_cstring(ssh,
4226: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
4227: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
4228: (r = sshpkt_send(ssh)) != 0 ||
4229: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4230: fatal_fr(r, "request tcpip-forward");
1.73 markus 4231: }
1.358 djm 4232: /* Assume that server accepts the request */
4233: success = 1;
1.73 markus 4234: if (success) {
1.305 djm 4235: /* Record that connection to this host/port is permitted. */
1.367 djm 4236: host_to_connect = listen_host = listen_path = NULL;
4237: port_to_connect = listen_port = 0;
1.336 millert 4238: if (fwd->connect_path != NULL) {
1.421 mbuhl 4239: host_to_connect = fwd->connect_path;
1.367 djm 4240: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 4241: } else {
1.421 mbuhl 4242: host_to_connect = fwd->connect_host;
1.367 djm 4243: port_to_connect = fwd->connect_port;
1.336 millert 4244: }
4245: if (fwd->listen_path != NULL) {
1.421 mbuhl 4246: listen_path = fwd->listen_path;
1.367 djm 4247: listen_port = PORT_STREAMLOCAL;
1.336 millert 4248: } else {
1.421 mbuhl 4249: listen_host = fwd->listen_host;
1.367 djm 4250: listen_port = fwd->listen_port;
4251: }
1.381 djm 4252: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 4253: host_to_connect, port_to_connect,
4254: listen_host, listen_path, listen_port, NULL);
1.44 markus 4255: }
1.367 djm 4256: return idx;
1.1 deraadt 4257: }
4258:
1.333 markus 4259: static int
1.381 djm 4260: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 4261: int requestedport)
1.333 markus 4262: {
4263: if (allowed_open->host_to_connect == NULL)
4264: return 0;
4265: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
4266: allowed_open->port_to_connect != requestedport)
4267: return 0;
1.351 dtucker 4268: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
4269: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 4270: return 0;
4271: return 1;
4272: }
4273:
4274: /*
1.336 millert 4275: * Note that in the listen host/port case
1.333 markus 4276: * we don't support FWD_PERMIT_ANY_PORT and
4277: * need to translate between the configured-host (listen_host)
4278: * and what we've sent to the remote server (channel_rfwd_bind_host)
4279: */
4280: static int
1.381 djm 4281: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 4282: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 4283: {
4284: const char *allowed_host;
4285:
4286: if (allowed_open->host_to_connect == NULL)
4287: return 0;
4288: if (allowed_open->listen_port != requestedport)
4289: return 0;
1.335 djm 4290: if (!translate && allowed_open->listen_host == NULL &&
4291: requestedhost == NULL)
4292: return 1;
1.333 markus 4293: allowed_host = translate ?
4294: channel_rfwd_bind_host(allowed_open->listen_host) :
4295: allowed_open->listen_host;
1.382 djm 4296: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 4297: strcmp(allowed_host, requestedhost) != 0)
4298: return 0;
4299: return 1;
4300: }
4301:
1.336 millert 4302: static int
1.381 djm 4303: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 4304: const char *requestedpath)
4305: {
4306: if (allowed_open->host_to_connect == NULL)
4307: return 0;
4308: if (allowed_open->listen_port != PORT_STREAMLOCAL)
4309: return 0;
4310: if (allowed_open->listen_path == NULL ||
4311: strcmp(allowed_open->listen_path, requestedpath) != 0)
4312: return 0;
4313: return 1;
4314: }
4315:
1.27 markus 4316: /*
1.208 deraadt 4317: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 4318: * local side.
4319: */
1.336 millert 4320: static int
1.367 djm 4321: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
4322: const char *host, u_short port)
1.202 djm 4323: {
1.367 djm 4324: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4325: struct permission_set *pset = &sc->local_perms;
1.367 djm 4326: int r;
4327: u_int i;
1.397 markus 4328: struct permission *perm = NULL;
1.202 djm 4329:
1.381 djm 4330: for (i = 0; i < pset->num_permitted_user; i++) {
4331: perm = &pset->permitted_user[i];
4332: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 4333: break;
1.381 djm 4334: perm = NULL;
1.202 djm 4335: }
1.381 djm 4336: if (perm == NULL) {
1.403 djm 4337: debug_f("requested forward not found");
1.312 djm 4338: return -1;
1.202 djm 4339: }
1.367 djm 4340: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4341: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
4342: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4343: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
4344: (r = sshpkt_put_u32(ssh, port)) != 0 ||
4345: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4346: fatal_fr(r, "send cancel");
1.367 djm 4347:
1.381 djm 4348: fwd_perm_clear(perm); /* unregister */
1.336 millert 4349:
4350: return 0;
4351: }
4352:
4353: /*
4354: * Request cancellation of remote forwarding of Unix domain socket
4355: * path from local side.
4356: */
4357: static int
1.367 djm 4358: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 4359: {
1.367 djm 4360: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4361: struct permission_set *pset = &sc->local_perms;
1.367 djm 4362: int r;
4363: u_int i;
1.397 markus 4364: struct permission *perm = NULL;
1.336 millert 4365:
1.381 djm 4366: for (i = 0; i < pset->num_permitted_user; i++) {
4367: perm = &pset->permitted_user[i];
4368: if (open_listen_match_streamlocal(perm, path))
1.336 millert 4369: break;
1.381 djm 4370: perm = NULL;
1.336 millert 4371: }
1.381 djm 4372: if (perm == NULL) {
1.403 djm 4373: debug_f("requested forward not found");
1.336 millert 4374: return -1;
4375: }
1.367 djm 4376: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4377: (r = sshpkt_put_cstring(ssh,
4378: "cancel-streamlocal-forward@openssh.com")) != 0 ||
4379: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4380: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
4381: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4382: fatal_fr(r, "send cancel");
1.367 djm 4383:
1.381 djm 4384: fwd_perm_clear(perm); /* unregister */
1.312 djm 4385:
4386: return 0;
1.202 djm 4387: }
4388:
4389: /*
1.336 millert 4390: * Request cancellation of remote forwarding of a connection from local side.
4391: */
4392: int
1.367 djm 4393: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 4394: {
4395: if (fwd->listen_path != NULL) {
1.367 djm 4396: return channel_request_rforward_cancel_streamlocal(ssh,
4397: fwd->listen_path);
1.336 millert 4398: } else {
1.367 djm 4399: return channel_request_rforward_cancel_tcpip(ssh,
4400: fwd->listen_host,
4401: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 4402: }
1.1 deraadt 4403: }
4404:
1.99 markus 4405: /*
1.381 djm 4406: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 4407: * usually called by the server, because the user could connect to any port
4408: * anyway, and the server has no way to know but to trust the client anyway.
4409: */
4410: void
1.381 djm 4411: channel_permit_all(struct ssh *ssh, int where)
4412: {
4413: struct permission_set *pset = permission_set_get(ssh, where);
4414:
4415: if (pset->num_permitted_user == 0)
4416: pset->all_permitted = 1;
4417: }
4418:
4419: /*
4420: * Permit the specified host/port for forwarding.
4421: */
4422: void
4423: channel_add_permission(struct ssh *ssh, int who, int where,
4424: char *host, int port)
4425: {
4426: int local = where == FORWARD_LOCAL;
4427: struct permission_set *pset = permission_set_get(ssh, where);
4428:
4429: debug("allow %s forwarding to host %s port %d",
4430: fwd_ident(who, where), host, port);
4431: /*
4432: * Remote forwards set listen_host/port, local forwards set
4433: * host/port_to_connect.
4434: */
4435: permission_set_add(ssh, who, where,
4436: local ? host : 0, local ? port : 0,
4437: local ? NULL : host, NULL, local ? 0 : port, NULL);
4438: pset->all_permitted = 0;
4439: }
4440:
4441: /*
4442: * Administratively disable forwarding.
4443: */
4444: void
4445: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4446: {
1.381 djm 4447: channel_clear_permission(ssh, FORWARD_ADM, where);
4448: permission_set_add(ssh, FORWARD_ADM, where,
4449: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4450: }
4451:
1.381 djm 4452: /*
4453: * Clear a list of permitted opens.
4454: */
1.101 markus 4455: void
1.381 djm 4456: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4457: {
1.381 djm 4458: struct permission **permp;
4459: u_int *npermp;
1.367 djm 4460:
1.381 djm 4461: permission_set_get_array(ssh, who, where, &permp, &npermp);
4462: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4463: *npermp = 0;
1.315 markus 4464: }
4465:
4466: /*
4467: * Update the listen port for a dynamic remote forward, after
4468: * the actual 'newport' has been allocated. If 'newport' < 0 is
4469: * passed then they entry will be invalidated.
4470: */
4471: void
1.381 djm 4472: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4473: {
1.381 djm 4474: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4475:
1.381 djm 4476: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
1.403 djm 4477: debug_f("index out of range: %d num_permitted_user %d",
4478: idx, pset->num_permitted_user);
1.315 markus 4479: return;
4480: }
4481: debug("%s allowed port %d for forwarding to host %s port %d",
4482: newport > 0 ? "Updating" : "Removing",
4483: newport,
1.381 djm 4484: pset->permitted_user[idx].host_to_connect,
4485: pset->permitted_user[idx].port_to_connect);
1.367 djm 4486: if (newport <= 0)
1.381 djm 4487: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4488: else {
1.381 djm 4489: pset->permitted_user[idx].listen_port =
1.404 djm 4490: (ssh->compat & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
1.315 markus 4491: }
1.99 markus 4492: }
4493:
1.314 dtucker 4494: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4495: int
4496: permitopen_port(const char *p)
4497: {
4498: int port;
4499:
4500: if (strcmp(p, "*") == 0)
4501: return FWD_PERMIT_ANY_PORT;
4502: if ((port = a2port(p)) > 0)
4503: return port;
4504: return -1;
4505: }
4506:
1.276 djm 4507: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4508: static int
1.276 djm 4509: connect_next(struct channel_connect *cctx)
1.41 markus 4510: {
1.276 djm 4511: int sock, saved_errno;
1.336 millert 4512: struct sockaddr_un *sunaddr;
1.367 djm 4513: char ntop[NI_MAXHOST];
4514: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4515:
1.276 djm 4516: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4517: switch (cctx->ai->ai_family) {
4518: case AF_UNIX:
4519: /* unix:pathname instead of host:port */
4520: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4521: strlcpy(ntop, "unix", sizeof(ntop));
4522: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4523: break;
4524: case AF_INET:
4525: case AF_INET6:
4526: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4527: ntop, sizeof(ntop), strport, sizeof(strport),
4528: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.420 djm 4529: error_f("getnameinfo failed");
1.336 millert 4530: continue;
4531: }
4532: break;
4533: default:
1.41 markus 4534: continue;
4535: }
1.420 djm 4536: debug_f("start for host %.100s ([%.100s]:%s)",
4537: cctx->host, ntop, strport);
1.300 dtucker 4538: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4539: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4540: if (cctx->ai->ai_next == NULL)
1.186 djm 4541: error("socket: %.100s", strerror(errno));
4542: else
4543: verbose("socket: %.100s", strerror(errno));
1.41 markus 4544: continue;
4545: }
1.205 djm 4546: if (set_nonblock(sock) == -1)
1.403 djm 4547: fatal_f("set_nonblock(%d)", sock);
1.276 djm 4548: if (connect(sock, cctx->ai->ai_addr,
4549: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
1.420 djm 4550: debug_f("host %.100s ([%.100s]:%s): %.100s",
4551: cctx->host, ntop, strport, strerror(errno));
1.276 djm 4552: saved_errno = errno;
1.41 markus 4553: close(sock);
1.276 djm 4554: errno = saved_errno;
1.89 stevesk 4555: continue; /* fail -- try next */
1.41 markus 4556: }
1.336 millert 4557: if (cctx->ai->ai_family != AF_UNIX)
4558: set_nodelay(sock);
1.420 djm 4559: debug_f("connect host %.100s ([%.100s]:%s) in progress, fd=%d",
4560: cctx->host, ntop, strport, sock);
1.276 djm 4561: cctx->ai = cctx->ai->ai_next;
4562: return sock;
4563: }
4564: return -1;
4565: }
1.41 markus 4566:
1.276 djm 4567: static void
4568: channel_connect_ctx_free(struct channel_connect *cctx)
4569: {
1.321 djm 4570: free(cctx->host);
1.336 millert 4571: if (cctx->aitop) {
4572: if (cctx->aitop->ai_family == AF_UNIX)
4573: free(cctx->aitop);
4574: else
4575: freeaddrinfo(cctx->aitop);
4576: }
1.329 tedu 4577: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4578: }
4579:
1.357 dtucker 4580: /*
1.372 markus 4581: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4582: * passing back the failure reason if appropriate.
4583: */
1.372 markus 4584: static int
4585: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4586: char *ctype, char *rname, struct channel_connect *cctx,
4587: int *reason, const char **errmsg)
1.276 djm 4588: {
4589: struct addrinfo hints;
4590: int gaierr;
4591: int sock = -1;
4592: char strport[NI_MAXSERV];
1.336 millert 4593:
4594: if (port == PORT_STREAMLOCAL) {
4595: struct sockaddr_un *sunaddr;
4596: struct addrinfo *ai;
4597:
4598: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4599: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4600: return -1;
1.336 millert 4601: }
4602:
4603: /*
4604: * Fake up a struct addrinfo for AF_UNIX connections.
4605: * channel_connect_ctx_free() must check ai_family
4606: * and use free() not freeaddirinfo() for AF_UNIX.
4607: */
4608: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4609: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4610: ai->ai_addr = (struct sockaddr *)(ai + 1);
4611: ai->ai_addrlen = sizeof(*sunaddr);
4612: ai->ai_family = AF_UNIX;
1.372 markus 4613: ai->ai_socktype = socktype;
1.336 millert 4614: ai->ai_protocol = PF_UNSPEC;
4615: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4616: sunaddr->sun_family = AF_UNIX;
4617: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4618: cctx->aitop = ai;
1.336 millert 4619: } else {
4620: memset(&hints, 0, sizeof(hints));
1.367 djm 4621: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4622: hints.ai_socktype = socktype;
1.336 millert 4623: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4624: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4625: != 0) {
4626: if (errmsg != NULL)
4627: *errmsg = ssh_gai_strerror(gaierr);
4628: if (reason != NULL)
4629: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4630: error("connect_to %.100s: unknown host (%s)", name,
4631: ssh_gai_strerror(gaierr));
1.372 markus 4632: return -1;
1.336 millert 4633: }
1.41 markus 4634: }
1.276 djm 4635:
1.372 markus 4636: cctx->host = xstrdup(name);
4637: cctx->port = port;
4638: cctx->ai = cctx->aitop;
1.276 djm 4639:
1.372 markus 4640: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4641: error("connect to %.100s port %d failed: %s",
1.336 millert 4642: name, port, strerror(errno));
1.372 markus 4643: return -1;
4644: }
4645:
4646: return sock;
4647: }
4648:
4649: /* Return CONNECTING channel to remote host:port or local socket path */
4650: static Channel *
4651: connect_to(struct ssh *ssh, const char *host, int port,
4652: char *ctype, char *rname)
4653: {
4654: struct channel_connect cctx;
4655: Channel *c;
4656: int sock;
4657:
4658: memset(&cctx, 0, sizeof(cctx));
4659: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4660: &cctx, NULL, NULL);
4661: if (sock == -1) {
1.276 djm 4662: channel_connect_ctx_free(&cctx);
4663: return NULL;
1.41 markus 4664: }
1.367 djm 4665: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4666: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4667: c->host_port = port;
4668: c->path = xstrdup(host);
1.276 djm 4669: c->connect_ctx = cctx;
1.372 markus 4670:
1.276 djm 4671: return c;
1.41 markus 4672: }
1.99 markus 4673:
1.354 markus 4674: /*
4675: * returns either the newly connected channel or the downstream channel
4676: * that needs to deal with this connection.
4677: */
1.276 djm 4678: Channel *
1.367 djm 4679: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4680: u_short listen_port, char *ctype, char *rname)
1.73 markus 4681: {
1.367 djm 4682: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4683: struct permission_set *pset = &sc->local_perms;
1.367 djm 4684: u_int i;
1.381 djm 4685: struct permission *perm;
1.99 markus 4686:
1.381 djm 4687: for (i = 0; i < pset->num_permitted_user; i++) {
4688: perm = &pset->permitted_user[i];
4689: if (open_listen_match_tcpip(perm,
4690: listen_host, listen_port, 1)) {
4691: if (perm->downstream)
4692: return perm->downstream;
4693: if (perm->port_to_connect == 0)
1.372 markus 4694: return rdynamic_connect_prepare(ssh,
4695: ctype, rname);
1.367 djm 4696: return connect_to(ssh,
1.381 djm 4697: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4698: ctype, rname);
1.276 djm 4699: }
4700: }
1.74 markus 4701: error("WARNING: Server requests forwarding for unknown listen_port %d",
4702: listen_port);
1.276 djm 4703: return NULL;
1.73 markus 4704: }
4705:
1.336 millert 4706: Channel *
1.367 djm 4707: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4708: char *ctype, char *rname)
1.336 millert 4709: {
1.367 djm 4710: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4711: struct permission_set *pset = &sc->local_perms;
1.367 djm 4712: u_int i;
1.381 djm 4713: struct permission *perm;
1.336 millert 4714:
1.381 djm 4715: for (i = 0; i < pset->num_permitted_user; i++) {
4716: perm = &pset->permitted_user[i];
4717: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4718: return connect_to(ssh,
1.381 djm 4719: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4720: ctype, rname);
1.336 millert 4721: }
4722: }
4723: error("WARNING: Server requests forwarding for unknown path %.100s",
4724: path);
4725: return NULL;
4726: }
4727:
1.99 markus 4728: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4729: Channel *
1.367 djm 4730: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4731: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4732: {
1.367 djm 4733: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4734: struct permission_set *pset = &sc->local_perms;
1.372 markus 4735: struct channel_connect cctx;
4736: Channel *c;
1.367 djm 4737: u_int i, permit, permit_adm = 1;
1.372 markus 4738: int sock;
1.381 djm 4739: struct permission *perm;
1.99 markus 4740:
1.381 djm 4741: permit = pset->all_permitted;
1.99 markus 4742: if (!permit) {
1.381 djm 4743: for (i = 0; i < pset->num_permitted_user; i++) {
4744: perm = &pset->permitted_user[i];
4745: if (open_match(perm, host, port)) {
1.99 markus 4746: permit = 1;
1.333 markus 4747: break;
4748: }
1.367 djm 4749: }
1.257 dtucker 4750: }
1.99 markus 4751:
1.381 djm 4752: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4753: permit_adm = 0;
1.381 djm 4754: for (i = 0; i < pset->num_permitted_admin; i++) {
4755: perm = &pset->permitted_admin[i];
4756: if (open_match(perm, host, port)) {
1.257 dtucker 4757: permit_adm = 1;
1.333 markus 4758: break;
4759: }
1.367 djm 4760: }
1.99 markus 4761: }
1.257 dtucker 4762:
4763: if (!permit || !permit_adm) {
1.391 florian 4764: logit("Received request from %.100s port %d to connect to "
4765: "host %.100s port %d, but the request was denied.",
4766: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4767: if (reason != NULL)
4768: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4769: return NULL;
1.99 markus 4770: }
1.372 markus 4771:
4772: memset(&cctx, 0, sizeof(cctx));
4773: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4774: &cctx, reason, errmsg);
4775: if (sock == -1) {
4776: channel_connect_ctx_free(&cctx);
4777: return NULL;
4778: }
4779:
4780: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4781: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4782: c->host_port = port;
4783: c->path = xstrdup(host);
4784: c->connect_ctx = cctx;
4785:
4786: return c;
1.336 millert 4787: }
4788:
4789: /* Check if connecting to that path is permitted and connect. */
4790: Channel *
1.367 djm 4791: channel_connect_to_path(struct ssh *ssh, const char *path,
4792: char *ctype, char *rname)
1.336 millert 4793: {
1.367 djm 4794: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4795: struct permission_set *pset = &sc->local_perms;
1.367 djm 4796: u_int i, permit, permit_adm = 1;
1.381 djm 4797: struct permission *perm;
1.336 millert 4798:
1.381 djm 4799: permit = pset->all_permitted;
1.336 millert 4800: if (!permit) {
1.381 djm 4801: for (i = 0; i < pset->num_permitted_user; i++) {
4802: perm = &pset->permitted_user[i];
4803: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4804: permit = 1;
4805: break;
4806: }
1.367 djm 4807: }
1.336 millert 4808: }
4809:
1.381 djm 4810: if (pset->num_permitted_admin > 0) {
1.336 millert 4811: permit_adm = 0;
1.381 djm 4812: for (i = 0; i < pset->num_permitted_admin; i++) {
4813: perm = &pset->permitted_admin[i];
4814: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4815: permit_adm = 1;
4816: break;
4817: }
1.367 djm 4818: }
1.336 millert 4819: }
4820:
4821: if (!permit || !permit_adm) {
4822: logit("Received request to connect to path %.100s, "
4823: "but the request was denied.", path);
4824: return NULL;
4825: }
1.367 djm 4826: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4827: }
4828:
4829: void
1.367 djm 4830: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4831: {
1.367 djm 4832: struct ssh_channels *sc = ssh->chanctxt;
4833: struct winsize ws;
4834: int r;
1.209 avsm 4835: u_int i;
1.204 djm 4836:
1.367 djm 4837: for (i = 0; i < sc->channels_alloc; i++) {
4838: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4839: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4840: continue;
1.393 deraadt 4841: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4842: continue;
1.367 djm 4843: channel_request_start(ssh, i, "window-change", 0);
4844: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4845: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4846: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4847: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4848: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4849: fatal_fr(r, "channel %u; send window-change", i);
1.204 djm 4850: }
1.372 markus 4851: }
4852:
4853: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4854: static Channel *
4855: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4856: {
4857: Channel *c;
4858: int r;
4859:
4860: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4861: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4862: c->host_port = 0;
4863: c->path = NULL;
4864:
4865: /*
4866: * We need to open the channel before we have a FD,
4867: * so that we can get SOCKS header from peer.
4868: */
4869: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4870: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4871: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4872: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 4873: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0)
4874: fatal_fr(r, "channel %i; confirm", c->self);
1.372 markus 4875: return c;
4876: }
4877:
4878: /* Return CONNECTING socket to remote host:port or local socket path */
4879: static int
4880: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4881: {
1.405 markus 4882: struct ssh_channels *sc = ssh->chanctxt;
4883: struct permission_set *pset = &sc->local_perms;
4884: struct permission *perm;
1.372 markus 4885: struct channel_connect cctx;
1.405 markus 4886: u_int i, permit_adm = 1;
1.372 markus 4887: int sock;
1.405 markus 4888:
4889: if (pset->num_permitted_admin > 0) {
4890: permit_adm = 0;
4891: for (i = 0; i < pset->num_permitted_admin; i++) {
4892: perm = &pset->permitted_admin[i];
4893: if (open_match(perm, c->path, c->host_port)) {
4894: permit_adm = 1;
4895: break;
4896: }
4897: }
4898: }
4899: if (!permit_adm) {
4900: debug_f("requested forward not permitted");
4901: return -1;
4902: }
1.372 markus 4903:
4904: memset(&cctx, 0, sizeof(cctx));
4905: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4906: NULL, &cctx, NULL, NULL);
4907: if (sock == -1)
4908: channel_connect_ctx_free(&cctx);
4909: else {
4910: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4911: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4912: c->connect_ctx = cctx;
4913: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4914: }
4915: return sock;
1.99 markus 4916: }
4917:
1.121 markus 4918: /* -- X11 forwarding */
1.1 deraadt 4919:
1.27 markus 4920: /*
4921: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4922: * Returns 0 and a suitable display number for the DISPLAY variable
4923: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4924: */
1.141 stevesk 4925: int
1.367 djm 4926: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4927: int x11_use_localhost, int single_connection,
4928: u_int *display_numberp, int **chanids)
1.1 deraadt 4929: {
1.149 markus 4930: Channel *nc = NULL;
1.31 markus 4931: int display_number, sock;
4932: u_short port;
1.35 markus 4933: struct addrinfo hints, *ai, *aitop;
4934: char strport[NI_MAXSERV];
4935: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4936:
1.224 markus 4937: if (chanids == NULL)
4938: return -1;
4939:
1.33 markus 4940: for (display_number = x11_display_offset;
1.148 deraadt 4941: display_number < MAX_DISPLAYS;
4942: display_number++) {
1.25 markus 4943: port = 6000 + display_number;
1.35 markus 4944: memset(&hints, 0, sizeof(hints));
1.367 djm 4945: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4946: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4947: hints.ai_socktype = SOCK_STREAM;
4948: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4949: if ((gaierr = getaddrinfo(NULL, strport,
4950: &hints, &aitop)) != 0) {
1.271 dtucker 4951: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4952: return -1;
1.25 markus 4953: }
1.35 markus 4954: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4955: if (ai->ai_family != AF_INET &&
4956: ai->ai_family != AF_INET6)
1.35 markus 4957: continue;
1.300 dtucker 4958: sock = socket(ai->ai_family, ai->ai_socktype,
4959: ai->ai_protocol);
1.393 deraadt 4960: if (sock == -1) {
1.35 markus 4961: error("socket: %.100s", strerror(errno));
1.203 markus 4962: freeaddrinfo(aitop);
1.141 stevesk 4963: return -1;
1.35 markus 4964: }
1.376 djm 4965: set_reuseaddr(sock);
1.393 deraadt 4966: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.403 djm 4967: debug2_f("bind port %d: %.100s", port,
4968: strerror(errno));
1.35 markus 4969: close(sock);
1.367 djm 4970: for (n = 0; n < num_socks; n++)
1.35 markus 4971: close(socks[n]);
4972: num_socks = 0;
4973: break;
4974: }
4975: socks[num_socks++] = sock;
4976: if (num_socks == NUM_SOCKS)
4977: break;
1.25 markus 4978: }
1.83 stevesk 4979: freeaddrinfo(aitop);
1.35 markus 4980: if (num_socks > 0)
4981: break;
1.25 markus 4982: }
4983: if (display_number >= MAX_DISPLAYS) {
4984: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4985: return -1;
1.25 markus 4986: }
4987: /* Start listening for connections on the socket. */
1.35 markus 4988: for (n = 0; n < num_socks; n++) {
4989: sock = socks[n];
1.393 deraadt 4990: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 4991: error("listen: %.100s", strerror(errno));
4992: close(sock);
1.141 stevesk 4993: return -1;
1.35 markus 4994: }
1.25 markus 4995: }
1.35 markus 4996:
4997: /* Allocate a channel for each socket. */
1.242 djm 4998: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4999: for (n = 0; n < num_socks; n++) {
5000: sock = socks[n];
1.424 djm 5001: nc = channel_new(ssh, "x11-listener",
1.51 markus 5002: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
5003: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 5004: 0, "X11 inet listener", 1);
1.167 markus 5005: nc->single_connection = single_connection;
1.224 markus 5006: (*chanids)[n] = nc->self;
1.35 markus 5007: }
1.224 markus 5008: (*chanids)[n] = -1;
1.1 deraadt 5009:
1.141 stevesk 5010: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 5011: *display_numberp = display_number;
1.367 djm 5012: return 0;
1.1 deraadt 5013: }
5014:
1.127 itojun 5015: static int
1.77 markus 5016: connect_local_xsocket(u_int dnr)
1.1 deraadt 5017: {
1.25 markus 5018: int sock;
5019: struct sockaddr_un addr;
5020:
1.147 stevesk 5021: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 deraadt 5022: if (sock == -1)
1.147 stevesk 5023: error("socket: %.100s", strerror(errno));
5024: memset(&addr, 0, sizeof(addr));
5025: addr.sun_family = AF_UNIX;
5026: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 5027: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 5028: return sock;
5029: close(sock);
1.25 markus 5030: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
5031: return -1;
1.1 deraadt 5032: }
5033:
1.51 markus 5034: int
1.367 djm 5035: x11_connect_display(struct ssh *ssh)
1.1 deraadt 5036: {
1.248 deraadt 5037: u_int display_number;
1.25 markus 5038: const char *display;
1.51 markus 5039: char buf[1024], *cp;
1.35 markus 5040: struct addrinfo hints, *ai, *aitop;
5041: char strport[NI_MAXSERV];
1.248 deraadt 5042: int gaierr, sock = 0;
1.25 markus 5043:
5044: /* Try to open a socket for the local X server. */
5045: display = getenv("DISPLAY");
5046: if (!display) {
5047: error("DISPLAY not set.");
1.51 markus 5048: return -1;
1.25 markus 5049: }
1.27 markus 5050: /*
5051: * Now we decode the value of the DISPLAY variable and make a
5052: * connection to the real X server.
5053: */
5054:
5055: /*
5056: * Check if it is a unix domain socket. Unix domain displays are in
5057: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
5058: */
1.25 markus 5059: if (strncmp(display, "unix:", 5) == 0 ||
5060: display[0] == ':') {
5061: /* Connect to the unix domain socket. */
1.367 djm 5062: if (sscanf(strrchr(display, ':') + 1, "%u",
5063: &display_number) != 1) {
5064: error("Could not parse display number from DISPLAY: "
5065: "%.100s", display);
1.51 markus 5066: return -1;
1.25 markus 5067: }
5068: /* Create a socket. */
5069: sock = connect_local_xsocket(display_number);
5070: if (sock < 0)
1.51 markus 5071: return -1;
1.25 markus 5072:
5073: /* OK, we now have a connection to the display. */
1.51 markus 5074: return sock;
1.25 markus 5075: }
1.27 markus 5076: /*
5077: * Connect to an inet socket. The DISPLAY value is supposedly
5078: * hostname:d[.s], where hostname may also be numeric IP address.
5079: */
1.145 stevesk 5080: strlcpy(buf, display, sizeof(buf));
1.25 markus 5081: cp = strchr(buf, ':');
5082: if (!cp) {
5083: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 5084: return -1;
1.25 markus 5085: }
5086: *cp = 0;
1.367 djm 5087: /*
5088: * buf now contains the host name. But first we parse the
5089: * display number.
5090: */
1.248 deraadt 5091: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 5092: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 5093: display);
1.51 markus 5094: return -1;
1.25 markus 5095: }
1.35 markus 5096:
5097: /* Look up the host address */
5098: memset(&hints, 0, sizeof(hints));
1.367 djm 5099: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 5100: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 5101: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 5102: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 5103: error("%.100s: unknown host. (%s)", buf,
5104: ssh_gai_strerror(gaierr));
1.51 markus 5105: return -1;
1.25 markus 5106: }
1.35 markus 5107: for (ai = aitop; ai; ai = ai->ai_next) {
5108: /* Create a socket. */
1.300 dtucker 5109: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 5110: if (sock == -1) {
1.194 markus 5111: debug2("socket: %.100s", strerror(errno));
1.41 markus 5112: continue;
5113: }
5114: /* Connect it to the display. */
1.393 deraadt 5115: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 5116: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 5117: 6000 + display_number, strerror(errno));
5118: close(sock);
5119: continue;
5120: }
5121: /* Success */
5122: break;
1.35 markus 5123: }
5124: freeaddrinfo(aitop);
5125: if (!ai) {
1.367 djm 5126: error("connect %.100s port %u: %.100s", buf,
5127: 6000 + display_number, strerror(errno));
1.51 markus 5128: return -1;
1.25 markus 5129: }
1.162 stevesk 5130: set_nodelay(sock);
1.51 markus 5131: return sock;
5132: }
5133:
5134: /*
1.27 markus 5135: * Requests forwarding of X11 connections, generates fake authentication
5136: * data, and enables authentication spoofing.
1.121 markus 5137: * This should be called in the client only.
1.27 markus 5138: */
1.49 markus 5139: void
1.367 djm 5140: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
5141: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 5142: {
1.367 djm 5143: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 5144: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 5145: u_int i, value;
1.367 djm 5146: const char *cp;
1.25 markus 5147: char *new_data;
1.367 djm 5148: int r, screen_number;
1.25 markus 5149:
1.367 djm 5150: if (sc->x11_saved_display == NULL)
5151: sc->x11_saved_display = xstrdup(disp);
5152: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 5153: error("x11_request_forwarding_with_spoofing: different "
5154: "$DISPLAY already forwarded");
5155: return;
5156: }
5157:
1.266 djm 5158: cp = strchr(disp, ':');
1.25 markus 5159: if (cp)
5160: cp = strchr(cp, '.');
5161: if (cp)
1.245 deraadt 5162: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 5163: else
5164: screen_number = 0;
5165:
1.367 djm 5166: if (sc->x11_saved_proto == NULL) {
1.219 djm 5167: /* Save protocol name. */
1.367 djm 5168: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 5169:
5170: /* Extract real authentication data. */
1.367 djm 5171: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 5172: for (i = 0; i < data_len; i++) {
1.403 djm 5173: if (sscanf(data + 2 * i, "%2x", &value) != 1) {
1.219 djm 5174: fatal("x11_request_forwarding: bad "
5175: "authentication data: %.100s", data);
1.403 djm 5176: }
1.367 djm 5177: sc->x11_saved_data[i] = value;
1.219 djm 5178: }
1.367 djm 5179: sc->x11_saved_data_len = data_len;
1.353 natano 5180:
5181: /* Generate fake data of the same length. */
1.367 djm 5182: sc->x11_fake_data = xmalloc(data_len);
5183: arc4random_buf(sc->x11_fake_data, data_len);
5184: sc->x11_fake_data_len = data_len;
1.25 markus 5185: }
5186:
5187: /* Convert the fake data into hex. */
1.367 djm 5188: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 5189:
5190: /* Send the request packet. */
1.367 djm 5191: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
5192: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
5193: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
5194: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
5195: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
5196: (r = sshpkt_send(ssh)) != 0 ||
5197: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 5198: fatal_fr(r, "send x11-req");
1.321 djm 5199: free(new_data);
1.1 deraadt 5200: }
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