Annotation of src/usr.bin/ssh/channels.c, Revision 1.432
1.432 ! dlg 1: /* $OpenBSD: channels.c,v 1.431 2023/06/05 13:24:36 millert 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: }
885: }
886: return 0;
887: }
888:
889: /* Returns the id of an open channel suitable for keepaliving */
890: int
1.367 djm 891: channel_find_open(struct ssh *ssh)
1.121 markus 892: {
1.209 avsm 893: u_int i;
1.121 markus 894: Channel *c;
895:
1.367 djm 896: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
897: c = ssh->chanctxt->channels[i];
1.368 djm 898: if (c == NULL || !c->have_remote_id)
1.121 markus 899: continue;
900: switch (c->type) {
901: case SSH_CHANNEL_CLOSED:
902: case SSH_CHANNEL_DYNAMIC:
1.372 markus 903: case SSH_CHANNEL_RDYNAMIC_OPEN:
904: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 905: case SSH_CHANNEL_X11_LISTENER:
906: case SSH_CHANNEL_PORT_LISTENER:
907: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 908: case SSH_CHANNEL_MUX_LISTENER:
909: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 910: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 911: case SSH_CHANNEL_OPENING:
912: case SSH_CHANNEL_CONNECTING:
913: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 914: case SSH_CHANNEL_ABANDONED:
1.336 millert 915: case SSH_CHANNEL_UNIX_LISTENER:
916: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 917: continue;
918: case SSH_CHANNEL_LARVAL:
919: case SSH_CHANNEL_AUTH_SOCKET:
920: case SSH_CHANNEL_OPEN:
921: case SSH_CHANNEL_X11_OPEN:
922: return i;
923: default:
1.403 djm 924: fatal_f("bad channel type %d", c->type);
1.121 markus 925: /* NOTREACHED */
926: }
927: }
928: return -1;
929: }
930:
1.385 djm 931: /* Returns the state of the channel's extended usage flag */
932: const char *
933: channel_format_extended_usage(const Channel *c)
934: {
935: if (c->efd == -1)
936: return "closed";
937:
938: switch (c->extended_usage) {
939: case CHAN_EXTENDED_WRITE:
940: return "write";
941: case CHAN_EXTENDED_READ:
942: return "read";
943: case CHAN_EXTENDED_IGNORE:
944: return "ignore";
945: default:
946: return "UNKNOWN";
947: }
948: }
949:
1.386 djm 950: static char *
951: channel_format_status(const Channel *c)
952: {
953: char *ret = NULL;
954:
1.425 djm 955: xasprintf(&ret, "t%d [%s] %s%u i%u/%zu o%u/%zu e[%s]/%zu "
1.411 djm 956: "fd %d/%d/%d sock %d cc %d io 0x%02x/0x%02x",
1.425 djm 957: c->type, c->xctype != NULL ? c->xctype : c->ctype,
1.386 djm 958: c->have_remote_id ? "r" : "nr", c->remote_id,
959: c->istate, sshbuf_len(c->input),
960: c->ostate, sshbuf_len(c->output),
961: channel_format_extended_usage(c), sshbuf_len(c->extended),
1.411 djm 962: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan,
963: c->io_want, c->io_ready);
1.386 djm 964: return ret;
965: }
966:
1.121 markus 967: /*
968: * Returns a message describing the currently open forwarded connections,
969: * suitable for sending to the client. The message contains crlf pairs for
970: * newlines.
971: */
972: char *
1.367 djm 973: channel_open_message(struct ssh *ssh)
1.121 markus 974: {
1.367 djm 975: struct sshbuf *buf;
1.121 markus 976: Channel *c;
1.209 avsm 977: u_int i;
1.367 djm 978: int r;
1.386 djm 979: char *cp, *ret;
1.121 markus 980:
1.367 djm 981: if ((buf = sshbuf_new()) == NULL)
1.403 djm 982: fatal_f("sshbuf_new");
1.367 djm 983: if ((r = sshbuf_putf(buf,
984: "The following connections are open:\r\n")) != 0)
1.403 djm 985: fatal_fr(r, "sshbuf_putf");
1.367 djm 986: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
987: c = ssh->chanctxt->channels[i];
1.121 markus 988: if (c == NULL)
989: continue;
990: switch (c->type) {
991: case SSH_CHANNEL_X11_LISTENER:
992: case SSH_CHANNEL_PORT_LISTENER:
993: case SSH_CHANNEL_RPORT_LISTENER:
994: case SSH_CHANNEL_CLOSED:
995: case SSH_CHANNEL_AUTH_SOCKET:
996: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 997: case SSH_CHANNEL_ABANDONED:
1.302 djm 998: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 999: case SSH_CHANNEL_UNIX_LISTENER:
1000: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 1001: continue;
1002: case SSH_CHANNEL_LARVAL:
1003: case SSH_CHANNEL_OPENING:
1004: case SSH_CHANNEL_CONNECTING:
1005: case SSH_CHANNEL_DYNAMIC:
1.372 markus 1006: case SSH_CHANNEL_RDYNAMIC_OPEN:
1007: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 1008: case SSH_CHANNEL_OPEN:
1009: case SSH_CHANNEL_X11_OPEN:
1.354 markus 1010: case SSH_CHANNEL_MUX_PROXY:
1011: case SSH_CHANNEL_MUX_CLIENT:
1.386 djm 1012: cp = channel_format_status(c);
1013: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
1014: c->self, c->remote_name, cp)) != 0) {
1015: free(cp);
1.403 djm 1016: fatal_fr(r, "sshbuf_putf");
1.386 djm 1017: }
1018: free(cp);
1.121 markus 1019: continue;
1020: default:
1.403 djm 1021: fatal_f("bad channel type %d", c->type);
1.121 markus 1022: /* NOTREACHED */
1023: }
1024: }
1.367 djm 1025: if ((ret = sshbuf_dup_string(buf)) == NULL)
1.403 djm 1026: fatal_f("sshbuf_dup_string");
1.367 djm 1027: sshbuf_free(buf);
1028: return ret;
1029: }
1030:
1031: static void
1032: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
1033: {
1034: int r;
1035:
1036: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
1037: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
1038: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1039: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1040: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
1.403 djm 1041: fatal_r(r, "%s: channel %i: open", where, c->self);
1.367 djm 1042: }
1.121 markus 1043: }
1044:
1045: void
1.367 djm 1046: channel_send_open(struct ssh *ssh, int id)
1.121 markus 1047: {
1.367 djm 1048: Channel *c = channel_lookup(ssh, id);
1049: int r;
1.180 deraadt 1050:
1.121 markus 1051: if (c == NULL) {
1.188 itojun 1052: logit("channel_send_open: %d: bad id", id);
1.121 markus 1053: return;
1054: }
1.184 markus 1055: debug2("channel %d: send open", id);
1.367 djm 1056: open_preamble(ssh, __func__, c, c->ctype);
1057: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1058: fatal_fr(r, "channel %i", c->self);
1.121 markus 1059: }
1060:
1061: void
1.367 djm 1062: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 1063: {
1.367 djm 1064: Channel *c = channel_lookup(ssh, id);
1065: int r;
1.180 deraadt 1066:
1.121 markus 1067: if (c == NULL) {
1.403 djm 1068: logit_f("%d: unknown channel id", id);
1.121 markus 1069: return;
1070: }
1.368 djm 1071: if (!c->have_remote_id)
1.403 djm 1072: fatal_f("channel %d: no remote id", c->self);
1.368 djm 1073:
1.204 djm 1074: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 1075: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
1076: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1077: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
1078: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
1.403 djm 1079: fatal_fr(r, "channel %i", c->self);
1.367 djm 1080: }
1.121 markus 1081: }
1.241 deraadt 1082:
1.121 markus 1083: void
1.367 djm 1084: channel_register_status_confirm(struct ssh *ssh, int id,
1085: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 1086: {
1087: struct channel_confirm *cc;
1088: Channel *c;
1089:
1.367 djm 1090: if ((c = channel_lookup(ssh, id)) == NULL)
1.403 djm 1091: fatal_f("%d: bad id", id);
1.275 djm 1092:
1.327 djm 1093: cc = xcalloc(1, sizeof(*cc));
1.275 djm 1094: cc->cb = cb;
1095: cc->abandon_cb = abandon_cb;
1096: cc->ctx = ctx;
1097: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
1098: }
1099:
1100: void
1.367 djm 1101: channel_register_open_confirm(struct ssh *ssh, int id,
1102: channel_open_fn *fn, void *ctx)
1.121 markus 1103: {
1.367 djm 1104: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1105:
1.121 markus 1106: if (c == NULL) {
1.403 djm 1107: logit_f("%d: bad id", id);
1.121 markus 1108: return;
1109: }
1.275 djm 1110: c->open_confirm = fn;
1111: c->open_confirm_ctx = ctx;
1.121 markus 1112: }
1.241 deraadt 1113:
1.121 markus 1114: void
1.367 djm 1115: channel_register_cleanup(struct ssh *ssh, int id,
1116: channel_callback_fn *fn, int do_close)
1.121 markus 1117: {
1.367 djm 1118: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1119:
1.121 markus 1120: if (c == NULL) {
1.403 djm 1121: logit_f("%d: bad id", id);
1.121 markus 1122: return;
1123: }
1.131 markus 1124: c->detach_user = fn;
1.225 djm 1125: c->detach_close = do_close;
1.121 markus 1126: }
1.241 deraadt 1127:
1.121 markus 1128: void
1.367 djm 1129: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 1130: {
1.367 djm 1131: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1132:
1.121 markus 1133: if (c == NULL) {
1.403 djm 1134: logit_f("%d: bad id", id);
1.121 markus 1135: return;
1.52 markus 1136: }
1.131 markus 1137: c->detach_user = NULL;
1.225 djm 1138: c->detach_close = 0;
1.121 markus 1139: }
1.241 deraadt 1140:
1.121 markus 1141: void
1.367 djm 1142: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1143: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1144: {
1.367 djm 1145: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1146:
1.121 markus 1147: if (c == NULL) {
1.403 djm 1148: logit_f("%d: bad id", id);
1.121 markus 1149: return;
1.52 markus 1150: }
1.231 reyk 1151: c->input_filter = ifn;
1152: c->output_filter = ofn;
1.279 djm 1153: c->filter_ctx = ctx;
1.280 djm 1154: c->filter_cleanup = cfn;
1.52 markus 1155: }
1156:
1.49 markus 1157: void
1.367 djm 1158: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1159: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1160: {
1.367 djm 1161: Channel *c = channel_lookup(ssh, id);
1162: int r;
1.180 deraadt 1163:
1.121 markus 1164: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1165: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1166: if (!c->have_remote_id)
1.403 djm 1167: fatal_f("channel %d: no remote id", c->self);
1.368 djm 1168:
1.367 djm 1169: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1170: c->type = SSH_CHANNEL_OPEN;
1.426 djm 1171: c->lastused = monotime();
1.168 markus 1172: c->local_window = c->local_window_max = window_max;
1.367 djm 1173:
1174: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1175: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1176: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1177: (r = sshpkt_send(ssh)) != 0)
1.403 djm 1178: fatal_fr(r, "channel %i", c->self);
1.1 deraadt 1179: }
1180:
1.127 itojun 1181: static void
1.410 djm 1182: channel_pre_listener(struct ssh *ssh, Channel *c)
1.41 markus 1183: {
1.410 djm 1184: c->io_want = SSH_CHAN_IO_SOCK_R;
1.41 markus 1185: }
1186:
1.127 itojun 1187: static void
1.410 djm 1188: channel_pre_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1189: {
1190: debug3("channel %d: waiting for connection", c->self);
1.410 djm 1191: c->io_want = SSH_CHAN_IO_SOCK_W;
1.75 markus 1192: }
1193:
1.127 itojun 1194: static void
1.410 djm 1195: channel_pre_open(struct ssh *ssh, Channel *c)
1.41 markus 1196: {
1.410 djm 1197: c->io_want = 0;
1.44 markus 1198: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1199: c->remote_window > 0 &&
1.367 djm 1200: sshbuf_len(c->input) < c->remote_window &&
1201: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1202: c->io_want |= SSH_CHAN_IO_RFD;
1.44 markus 1203: if (c->ostate == CHAN_OUTPUT_OPEN ||
1204: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1205: if (sshbuf_len(c->output) > 0) {
1.410 djm 1206: c->io_want |= SSH_CHAN_IO_WFD;
1.44 markus 1207: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1208: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1209: debug2("channel %d: "
1210: "obuf_empty delayed efd %d/(%zu)", c->self,
1211: c->efd, sshbuf_len(c->extended));
1.172 markus 1212: else
1.367 djm 1213: chan_obuf_empty(ssh, c);
1.44 markus 1214: }
1215: }
1216: /** XXX check close conditions, too */
1.358 djm 1217: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1218: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1219: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1220: sshbuf_len(c->extended) > 0)
1.410 djm 1221: c->io_want |= SSH_CHAN_IO_EFD_W;
1.306 djm 1222: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1223: (c->extended_usage == CHAN_EXTENDED_READ ||
1224: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1225: sshbuf_len(c->extended) < c->remote_window)
1.410 djm 1226: c->io_want |= SSH_CHAN_IO_EFD_R;
1.44 markus 1227: }
1.204 djm 1228: /* XXX: What about efd? races? */
1.44 markus 1229: }
1230:
1.41 markus 1231: /*
1232: * This is a special state for X11 authentication spoofing. An opened X11
1233: * connection (when authentication spoofing is being done) remains in this
1234: * state until the first packet has been completely read. The authentication
1235: * data in that packet is then substituted by the real data if it matches the
1236: * fake data, and the channel is put into normal mode.
1.51 markus 1237: * XXX All this happens at the client side.
1.121 markus 1238: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1239: */
1.127 itojun 1240: static int
1.367 djm 1241: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1242: {
1.367 djm 1243: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1244: u_char *ucp;
1245: u_int proto_len, data_len;
1.25 markus 1246:
1.347 djm 1247: /* Is this being called after the refusal deadline? */
1.367 djm 1248: if (sc->x11_refuse_time != 0 &&
1.428 dtucker 1249: monotime() >= sc->x11_refuse_time) {
1.347 djm 1250: verbose("Rejected X11 connection after ForwardX11Timeout "
1251: "expired");
1252: return -1;
1253: }
1254:
1.41 markus 1255: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1256: if (sshbuf_len(b) < 12)
1.41 markus 1257: return 0;
1258:
1259: /* Parse the lengths of variable-length fields. */
1.367 djm 1260: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1261: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1262: proto_len = 256 * ucp[6] + ucp[7];
1263: data_len = 256 * ucp[8] + ucp[9];
1264: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1265: proto_len = ucp[6] + 256 * ucp[7];
1266: data_len = ucp[8] + 256 * ucp[9];
1267: } else {
1.194 markus 1268: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1269: ucp[0]);
1.41 markus 1270: return -1;
1271: }
1272:
1273: /* Check if the whole packet is in buffer. */
1.367 djm 1274: if (sshbuf_len(b) <
1.41 markus 1275: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1276: return 0;
1277:
1278: /* Check if authentication protocol matches. */
1.367 djm 1279: if (proto_len != strlen(sc->x11_saved_proto) ||
1280: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1281: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1282: return -1;
1283: }
1284: /* Check if authentication data matches our fake data. */
1.367 djm 1285: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1286: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1287: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1288: debug2("X11 auth data does not match fake data.");
1.41 markus 1289: return -1;
1290: }
1291: /* Check fake data length */
1.367 djm 1292: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1293: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1294: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1295: return -1;
1296: }
1297: /*
1298: * Received authentication protocol and data match
1299: * our fake data. Substitute the fake data with real
1300: * data.
1301: */
1302: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1303: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1304: return 1;
1305: }
1306:
1.423 djm 1307: void
1308: channel_force_close(struct ssh *ssh, Channel *c, int abandon)
1309: {
1310: debug3_f("channel %d: forcibly closing", c->self);
1311: if (c->istate == CHAN_INPUT_OPEN)
1312: chan_read_failed(ssh, c);
1313: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1314: sshbuf_reset(c->input);
1315: chan_ibuf_empty(ssh, c);
1316: }
1317: if (c->ostate == CHAN_OUTPUT_OPEN ||
1318: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1319: sshbuf_reset(c->output);
1320: chan_write_failed(ssh, c);
1321: }
1322: if (c->detach_user)
1323: c->detach_user(ssh, c->self, 1, NULL);
1324: if (c->efd != -1)
1325: channel_close_fd(ssh, c, &c->efd);
1326: if (abandon)
1327: c->type = SSH_CHANNEL_ABANDONED;
1.426 djm 1328: /* exempt from inactivity timeouts */
1329: c->inactive_deadline = 0;
1330: c->lastused = 0;
1.423 djm 1331: }
1332:
1.127 itojun 1333: static void
1.410 djm 1334: channel_pre_x11_open(struct ssh *ssh, Channel *c)
1.41 markus 1335: {
1.367 djm 1336: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1337:
1338: /* c->force_drain = 1; */
1339:
1.41 markus 1340: if (ret == 1) {
1341: c->type = SSH_CHANNEL_OPEN;
1.426 djm 1342: c->lastused = monotime();
1.410 djm 1343: channel_pre_open(ssh, c);
1.41 markus 1344: } else if (ret == -1) {
1.423 djm 1345: logit("X11 connection rejected because of wrong "
1346: "authentication.");
1.367 djm 1347: debug2("X11 rejected %d i%d/o%d",
1348: c->self, c->istate, c->ostate);
1.423 djm 1349: channel_force_close(ssh, c, 0);
1.41 markus 1350: }
1351: }
1.25 markus 1352:
1.302 djm 1353: static void
1.410 djm 1354: channel_pre_mux_client(struct ssh *ssh, Channel *c)
1.302 djm 1355: {
1.410 djm 1356: c->io_want = 0;
1.304 djm 1357: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1358: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1359: c->io_want |= SSH_CHAN_IO_RFD;
1.302 djm 1360: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1361: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1362: sshbuf_reset(c->input);
1363: chan_ibuf_empty(ssh, c);
1.302 djm 1364: /* Start output drain. XXX just kill chan? */
1.367 djm 1365: chan_rcvd_oclose(ssh, c);
1.302 djm 1366: }
1367: if (c->ostate == CHAN_OUTPUT_OPEN ||
1368: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1369: if (sshbuf_len(c->output) > 0)
1.410 djm 1370: c->io_want |= SSH_CHAN_IO_WFD;
1.302 djm 1371: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1372: chan_obuf_empty(ssh, c);
1.302 djm 1373: }
1374: }
1375:
1.104 markus 1376: /* try to decode a socks4 header */
1.127 itojun 1377: static int
1.372 markus 1378: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1379: {
1.367 djm 1380: const u_char *p;
1381: char *host;
1.292 djm 1382: u_int len, have, i, found, need;
1.148 deraadt 1383: char username[256];
1.103 markus 1384: struct {
1385: u_int8_t version;
1386: u_int8_t command;
1387: u_int16_t dest_port;
1.104 markus 1388: struct in_addr dest_addr;
1.103 markus 1389: } s4_req, s4_rsp;
1.367 djm 1390: int r;
1.103 markus 1391:
1.104 markus 1392: debug2("channel %d: decode socks4", c->self);
1.109 markus 1393:
1.372 markus 1394: have = sshbuf_len(input);
1.109 markus 1395: len = sizeof(s4_req);
1396: if (have < len)
1397: return 0;
1.372 markus 1398: p = sshbuf_ptr(input);
1.292 djm 1399:
1400: need = 1;
1401: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1402: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1403: debug2("channel %d: socks4a request", c->self);
1404: /* ... and needs an extra string (the hostname) */
1405: need = 2;
1406: }
1407: /* Check for terminating NUL on the string(s) */
1.109 markus 1408: for (found = 0, i = len; i < have; i++) {
1409: if (p[i] == '\0') {
1.292 djm 1410: found++;
1411: if (found == need)
1412: break;
1.109 markus 1413: }
1414: if (i > 1024) {
1415: /* the peer is probably sending garbage */
1416: debug("channel %d: decode socks4: too long",
1417: c->self);
1418: return -1;
1419: }
1420: }
1.292 djm 1421: if (found < need)
1.109 markus 1422: return 0;
1.372 markus 1423: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1424: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1425: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1426: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.403 djm 1427: debug_r(r, "channels %d: decode socks4", c->self);
1.367 djm 1428: return -1;
1429: }
1.372 markus 1430: have = sshbuf_len(input);
1431: p = sshbuf_ptr(input);
1.364 djm 1432: if (memchr(p, '\0', have) == NULL) {
1.403 djm 1433: error("channel %d: decode socks4: unterminated user", c->self);
1.364 djm 1434: return -1;
1435: }
1.103 markus 1436: len = strlen(p);
1.106 markus 1437: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1438: len++; /* trailing '\0' */
1.103 markus 1439: strlcpy(username, p, sizeof(username));
1.403 djm 1440: if ((r = sshbuf_consume(input, len)) != 0)
1441: fatal_fr(r, "channel %d: consume", c->self);
1.321 djm 1442: free(c->path);
1443: c->path = NULL;
1.292 djm 1444: if (need == 1) { /* SOCKS4: one string */
1445: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1446: c->path = xstrdup(host);
1.292 djm 1447: } else { /* SOCKS4A: two strings */
1.372 markus 1448: have = sshbuf_len(input);
1449: p = sshbuf_ptr(input);
1.364 djm 1450: if (memchr(p, '\0', have) == NULL) {
1451: error("channel %d: decode socks4a: host not nul "
1452: "terminated", c->self);
1453: return -1;
1454: }
1.292 djm 1455: len = strlen(p);
1456: debug2("channel %d: decode socks4a: host %s/%d",
1457: c->self, p, len);
1458: len++; /* trailing '\0' */
1.293 djm 1459: if (len > NI_MAXHOST) {
1.292 djm 1460: error("channel %d: hostname \"%.100s\" too long",
1461: c->self, p);
1462: return -1;
1463: }
1.293 djm 1464: c->path = xstrdup(p);
1.403 djm 1465: if ((r = sshbuf_consume(input, len)) != 0)
1466: fatal_fr(r, "channel %d: consume", c->self);
1.292 djm 1467: }
1.103 markus 1468: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1469:
1.194 markus 1470: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1471: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1472:
1.104 markus 1473: if (s4_req.command != 1) {
1.292 djm 1474: debug("channel %d: cannot handle: %s cn %d",
1475: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1476: return -1;
1.103 markus 1477: }
1.104 markus 1478: s4_rsp.version = 0; /* vn: 0 for reply */
1479: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1480: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1481: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.403 djm 1482: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0)
1483: fatal_fr(r, "channel %d: append reply", c->self);
1.104 markus 1484: return 1;
1485: }
1486:
1.193 markus 1487: /* try to decode a socks5 header */
1488: #define SSH_SOCKS5_AUTHDONE 0x1000
1489: #define SSH_SOCKS5_NOAUTH 0x00
1490: #define SSH_SOCKS5_IPV4 0x01
1491: #define SSH_SOCKS5_DOMAIN 0x03
1492: #define SSH_SOCKS5_IPV6 0x04
1493: #define SSH_SOCKS5_CONNECT 0x01
1494: #define SSH_SOCKS5_SUCCESS 0x00
1495:
1496: static int
1.372 markus 1497: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1498: {
1.367 djm 1499: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1500: struct {
1501: u_int8_t version;
1502: u_int8_t command;
1503: u_int8_t reserved;
1504: u_int8_t atyp;
1505: } s5_req, s5_rsp;
1506: u_int16_t dest_port;
1.324 djm 1507: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1508: const u_char *p;
1.252 djm 1509: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1510: int r;
1.193 markus 1511:
1512: debug2("channel %d: decode socks5", c->self);
1.372 markus 1513: p = sshbuf_ptr(input);
1.193 markus 1514: if (p[0] != 0x05)
1515: return -1;
1.372 markus 1516: have = sshbuf_len(input);
1.193 markus 1517: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1518: /* format: ver | nmethods | methods */
1.198 djm 1519: if (have < 2)
1.193 markus 1520: return 0;
1521: nmethods = p[1];
1522: if (have < nmethods + 2)
1523: return 0;
1524: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1525: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1526: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1527: found = 1;
1528: break;
1529: }
1530: }
1531: if (!found) {
1532: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1533: c->self);
1534: return -1;
1535: }
1.403 djm 1536: if ((r = sshbuf_consume(input, nmethods + 2)) != 0)
1537: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1538: /* version, method */
1.372 markus 1539: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1.403 djm 1540: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0)
1541: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1542: c->flags |= SSH_SOCKS5_AUTHDONE;
1543: debug2("channel %d: socks5 auth done", c->self);
1544: return 0; /* need more */
1545: }
1546: debug2("channel %d: socks5 post auth", c->self);
1547: if (have < sizeof(s5_req)+1)
1548: return 0; /* need more */
1.247 deraadt 1549: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1550: if (s5_req.version != 0x05 ||
1551: s5_req.command != SSH_SOCKS5_CONNECT ||
1552: s5_req.reserved != 0x00) {
1.194 markus 1553: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1554: return -1;
1555: }
1.213 deraadt 1556: switch (s5_req.atyp){
1.193 markus 1557: case SSH_SOCKS5_IPV4:
1558: addrlen = 4;
1559: af = AF_INET;
1560: break;
1561: case SSH_SOCKS5_DOMAIN:
1562: addrlen = p[sizeof(s5_req)];
1563: af = -1;
1564: break;
1565: case SSH_SOCKS5_IPV6:
1566: addrlen = 16;
1567: af = AF_INET6;
1568: break;
1569: default:
1.194 markus 1570: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1571: return -1;
1572: }
1.252 djm 1573: need = sizeof(s5_req) + addrlen + 2;
1574: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1575: need++;
1576: if (have < need)
1.193 markus 1577: return 0;
1.403 djm 1578: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0)
1579: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1580: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1581: /* host string length */
1.403 djm 1582: if ((r = sshbuf_consume(input, 1)) != 0)
1583: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1584: }
1.372 markus 1585: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1586: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.403 djm 1587: debug_r(r, "channel %d: parse addr/port", c->self);
1.367 djm 1588: return -1;
1589: }
1.193 markus 1590: dest_addr[addrlen] = '\0';
1.321 djm 1591: free(c->path);
1592: c->path = NULL;
1.293 djm 1593: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1594: if (addrlen >= NI_MAXHOST) {
1.293 djm 1595: error("channel %d: dynamic request: socks5 hostname "
1596: "\"%.100s\" too long", c->self, dest_addr);
1597: return -1;
1598: }
1599: c->path = xstrdup(dest_addr);
1600: } else {
1601: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1602: return -1;
1603: c->path = xstrdup(ntop);
1604: }
1.193 markus 1605: c->host_port = ntohs(dest_port);
1.198 djm 1606:
1.194 markus 1607: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1608: c->self, c->path, c->host_port, s5_req.command);
1609:
1610: s5_rsp.version = 0x05;
1611: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1612: s5_rsp.reserved = 0; /* ignored */
1613: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1614: dest_port = 0; /* ignored */
1615:
1.372 markus 1616: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1617: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1618: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.403 djm 1619: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1620: return 1;
1.301 dtucker 1621: }
1622:
1623: Channel *
1.367 djm 1624: channel_connect_stdio_fwd(struct ssh *ssh,
1.432 ! dlg 1625: const char *host_to_connect, int port_to_connect,
1.407 djm 1626: int in, int out, int nonblock)
1.301 dtucker 1627: {
1628: Channel *c;
1629:
1.403 djm 1630: debug_f("%s:%d", host_to_connect, port_to_connect);
1.301 dtucker 1631:
1.367 djm 1632: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1633: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.407 djm 1634: 0, "stdio-forward", nonblock);
1.301 dtucker 1635:
1636: c->path = xstrdup(host_to_connect);
1637: c->host_port = port_to_connect;
1638: c->listening_port = 0;
1639: c->force_drain = 1;
1640:
1.367 djm 1641: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1.432 ! dlg 1642: port_open_helper(ssh, c, port_to_connect == PORT_STREAMLOCAL ?
! 1643: "direct-streamlocal@openssh.com" : "direct-tcpip");
1.301 dtucker 1644:
1645: return c;
1.193 markus 1646: }
1647:
1.104 markus 1648: /* dynamic port forwarding */
1.127 itojun 1649: static void
1.410 djm 1650: channel_pre_dynamic(struct ssh *ssh, Channel *c)
1.104 markus 1651: {
1.367 djm 1652: const u_char *p;
1.217 djm 1653: u_int have;
1654: int ret;
1.103 markus 1655:
1.410 djm 1656: c->io_want = 0;
1.367 djm 1657: have = sshbuf_len(c->input);
1.104 markus 1658: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1659: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1660: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1661: if (have < 3) {
1.104 markus 1662: /* need more */
1.410 djm 1663: c->io_want |= SSH_CHAN_IO_RFD;
1.104 markus 1664: return;
1665: }
1666: /* try to guess the protocol */
1.367 djm 1667: p = sshbuf_ptr(c->input);
1668: /* XXX sshbuf_peek_u8? */
1.104 markus 1669: switch (p[0]) {
1670: case 0x04:
1.372 markus 1671: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1672: break;
1673: case 0x05:
1.372 markus 1674: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1675: break;
1676: default:
1677: ret = -1;
1678: break;
1679: }
1680: if (ret < 0) {
1.367 djm 1681: chan_mark_dead(ssh, c);
1.104 markus 1682: } else if (ret == 0) {
1683: debug2("channel %d: pre_dynamic: need more", c->self);
1684: /* need more */
1.410 djm 1685: c->io_want |= SSH_CHAN_IO_RFD;
1.372 markus 1686: if (sshbuf_len(c->output))
1.410 djm 1687: c->io_want |= SSH_CHAN_IO_WFD;
1.104 markus 1688: } else {
1689: /* switch to the next state */
1690: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1691: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1692: }
1.103 markus 1693: }
1694:
1.372 markus 1695: /* simulate read-error */
1696: static void
1697: rdynamic_close(struct ssh *ssh, Channel *c)
1698: {
1699: c->type = SSH_CHANNEL_OPEN;
1.423 djm 1700: channel_force_close(ssh, c, 0);
1.372 markus 1701: }
1702:
1703: /* reverse dynamic port forwarding */
1704: static void
1.411 djm 1705: channel_before_prepare_io_rdynamic(struct ssh *ssh, Channel *c)
1.372 markus 1706: {
1707: const u_char *p;
1708: u_int have, len;
1709: int r, ret;
1710:
1711: have = sshbuf_len(c->output);
1712: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1713: /* sshbuf_dump(c->output, stderr); */
1714: /* EOF received */
1715: if (c->flags & CHAN_EOF_RCVD) {
1.403 djm 1716: if ((r = sshbuf_consume(c->output, have)) != 0)
1717: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1718: rdynamic_close(ssh, c);
1719: return;
1720: }
1721: /* check if the fixed size part of the packet is in buffer. */
1722: if (have < 3)
1723: return;
1724: /* try to guess the protocol */
1725: p = sshbuf_ptr(c->output);
1726: switch (p[0]) {
1727: case 0x04:
1728: /* switch input/output for reverse forwarding */
1729: ret = channel_decode_socks4(c, c->output, c->input);
1730: break;
1731: case 0x05:
1732: ret = channel_decode_socks5(c, c->output, c->input);
1733: break;
1734: default:
1735: ret = -1;
1736: break;
1737: }
1738: if (ret < 0) {
1739: rdynamic_close(ssh, c);
1740: } else if (ret == 0) {
1741: debug2("channel %d: pre_rdynamic: need more", c->self);
1742: /* send socks request to peer */
1743: len = sshbuf_len(c->input);
1744: if (len > 0 && len < c->remote_window) {
1745: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1746: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1747: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1748: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 1749: fatal_fr(r, "channel %i: rdynamic", c->self);
1.372 markus 1750: }
1.403 djm 1751: if ((r = sshbuf_consume(c->input, len)) != 0)
1752: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1753: c->remote_window -= len;
1754: }
1755: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1756: /* the connect failed */
1757: rdynamic_close(ssh, c);
1758: }
1759: }
1760:
1.41 markus 1761: /* This is our fake X11 server socket. */
1.127 itojun 1762: static void
1.410 djm 1763: channel_post_x11_listener(struct ssh *ssh, Channel *c)
1.41 markus 1764: {
1.113 markus 1765: Channel *nc;
1.285 djm 1766: struct sockaddr_storage addr;
1.367 djm 1767: int r, newsock, oerrno, remote_port;
1.41 markus 1768: socklen_t addrlen;
1.85 markus 1769: char buf[16384], *remote_ipaddr;
1.25 markus 1770:
1.410 djm 1771: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1772: return;
1773:
1774: debug("X11 connection requested.");
1775: addrlen = sizeof(addr);
1776: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1777: if (c->single_connection) {
1778: oerrno = errno;
1779: debug2("single_connection: closing X11 listener.");
1.407 djm 1780: channel_close_fd(ssh, c, &c->sock);
1.367 djm 1781: chan_mark_dead(ssh, c);
1782: errno = oerrno;
1783: }
1.393 deraadt 1784: if (newsock == -1) {
1.367 djm 1785: if (errno != EINTR && errno != EWOULDBLOCK &&
1786: errno != ECONNABORTED)
1787: error("accept: %.100s", strerror(errno));
1788: if (errno == EMFILE || errno == ENFILE)
1789: c->notbefore = monotime() + 1;
1790: return;
1791: }
1792: set_nodelay(newsock);
1793: remote_ipaddr = get_peer_ipaddr(newsock);
1794: remote_port = get_peer_port(newsock);
1795: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1796: remote_ipaddr, remote_port);
1797:
1.424 djm 1798: nc = channel_new(ssh, "x11-connection",
1.367 djm 1799: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1800: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1801: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1802: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1803: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.403 djm 1804: fatal_fr(r, "channel %i: reply", c->self);
1.41 markus 1805: }
1.367 djm 1806: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1807: fatal_fr(r, "channel %i: send", c->self);
1.367 djm 1808: free(remote_ipaddr);
1.41 markus 1809: }
1.25 markus 1810:
1.127 itojun 1811: static void
1.367 djm 1812: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1813: {
1.328 djm 1814: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1815: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1816: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1817: int remote_port = get_peer_port(c->sock);
1.367 djm 1818: int r;
1.303 djm 1819:
1820: if (remote_port == -1) {
1821: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1822: free(remote_ipaddr);
1.303 djm 1823: remote_ipaddr = xstrdup("127.0.0.1");
1824: remote_port = 65535;
1825: }
1.103 markus 1826:
1.367 djm 1827: free(c->remote_name);
1828: xasprintf(&c->remote_name,
1.103 markus 1829: "%s: listening port %d for %.100s port %d, "
1.328 djm 1830: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1831: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1832: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1833:
1.367 djm 1834: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1835: if (strcmp(rtype, "direct-tcpip") == 0) {
1836: /* target host, port */
1.367 djm 1837: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1838: (r = sshpkt_put_u32(ssh, c->host_port)) != 0)
1839: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1840: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1841: /* target path */
1.403 djm 1842: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1843: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1844: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1845: /* listen path */
1.403 djm 1846: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1847: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1848: } else {
1.358 djm 1849: /* listen address, port */
1.367 djm 1850: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1851: (r = sshpkt_put_u32(ssh, local_port)) != 0)
1852: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1853: }
1854: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1855: /* reserved for future owner/mode info */
1.403 djm 1856: if ((r = sshpkt_put_cstring(ssh, "")) != 0)
1857: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1858: } else {
1859: /* originator host and port */
1.367 djm 1860: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1.403 djm 1861: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0)
1862: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1863: }
1.367 djm 1864: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1865: fatal_fr(r, "channel %i: send", c->self);
1.321 djm 1866: free(remote_ipaddr);
1.328 djm 1867: free(local_ipaddr);
1.103 markus 1868: }
1869:
1.347 djm 1870: void
1.428 dtucker 1871: channel_set_x11_refuse_time(struct ssh *ssh, time_t refuse_time)
1.347 djm 1872: {
1.367 djm 1873: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1874: }
1875:
1.41 markus 1876: /*
1877: * This socket is listening for connections to a forwarded TCP/IP port.
1878: */
1.127 itojun 1879: static void
1.410 djm 1880: channel_post_port_listener(struct ssh *ssh, Channel *c)
1.41 markus 1881: {
1.103 markus 1882: Channel *nc;
1.285 djm 1883: struct sockaddr_storage addr;
1.113 markus 1884: int newsock, nextstate;
1.41 markus 1885: socklen_t addrlen;
1.103 markus 1886: char *rtype;
1.73 markus 1887:
1.410 djm 1888: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1889: return;
1890:
1891: debug("Connection to port %d forwarding to %.100s port %d requested.",
1892: c->listening_port, c->path, c->host_port);
1.103 markus 1893:
1.367 djm 1894: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1895: nextstate = SSH_CHANNEL_OPENING;
1896: rtype = "forwarded-tcpip";
1897: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1898: nextstate = SSH_CHANNEL_OPENING;
1899: rtype = "forwarded-streamlocal@openssh.com";
1900: } else if (c->host_port == PORT_STREAMLOCAL) {
1901: nextstate = SSH_CHANNEL_OPENING;
1902: rtype = "direct-streamlocal@openssh.com";
1903: } else if (c->host_port == 0) {
1904: nextstate = SSH_CHANNEL_DYNAMIC;
1905: rtype = "dynamic-tcpip";
1906: } else {
1907: nextstate = SSH_CHANNEL_OPENING;
1908: rtype = "direct-tcpip";
1909: }
1.103 markus 1910:
1.367 djm 1911: addrlen = sizeof(addr);
1912: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1913: if (newsock == -1) {
1.367 djm 1914: if (errno != EINTR && errno != EWOULDBLOCK &&
1915: errno != ECONNABORTED)
1916: error("accept: %.100s", strerror(errno));
1917: if (errno == EMFILE || errno == ENFILE)
1918: c->notbefore = monotime() + 1;
1919: return;
1.41 markus 1920: }
1.367 djm 1921: if (c->host_port != PORT_STREAMLOCAL)
1922: set_nodelay(newsock);
1923: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1924: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1925: nc->listening_port = c->listening_port;
1926: nc->host_port = c->host_port;
1927: if (c->path != NULL)
1928: nc->path = xstrdup(c->path);
1929:
1930: if (nextstate != SSH_CHANNEL_DYNAMIC)
1931: port_open_helper(ssh, nc, rtype);
1.41 markus 1932: }
1.25 markus 1933:
1.41 markus 1934: /*
1935: * This is the authentication agent socket listening for connections from
1936: * clients.
1937: */
1.127 itojun 1938: static void
1.410 djm 1939: channel_post_auth_listener(struct ssh *ssh, Channel *c)
1.41 markus 1940: {
1.113 markus 1941: Channel *nc;
1.367 djm 1942: int r, newsock;
1.285 djm 1943: struct sockaddr_storage addr;
1.41 markus 1944: socklen_t addrlen;
1.25 markus 1945:
1.410 djm 1946: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1947: return;
1948:
1949: addrlen = sizeof(addr);
1950: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1951: if (newsock == -1) {
1.367 djm 1952: error("accept from auth socket: %.100s", strerror(errno));
1953: if (errno == EMFILE || errno == ENFILE)
1954: c->notbefore = monotime() + 1;
1955: return;
1.41 markus 1956: }
1.424 djm 1957: nc = channel_new(ssh, "agent-connection",
1.367 djm 1958: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1959: c->local_window_max, c->local_maxpacket,
1960: 0, "accepted auth socket", 1);
1961: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1962: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1963: fatal_fr(r, "channel %i", c->self);
1.41 markus 1964: }
1.25 markus 1965:
1.127 itojun 1966: static void
1.410 djm 1967: channel_post_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1968: {
1.372 markus 1969: int err = 0, sock, isopen, r;
1.129 stevesk 1970: socklen_t sz = sizeof(err);
1.114 markus 1971:
1.410 djm 1972: if ((c->io_ready & SSH_CHAN_IO_SOCK_W) == 0)
1.367 djm 1973: return;
1.368 djm 1974: if (!c->have_remote_id)
1.403 djm 1975: fatal_f("channel %d: no remote id", c->self);
1.372 markus 1976: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1977: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.429 djm 1978:
1.393 deraadt 1979: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 1980: err = errno;
1981: error("getsockopt SO_ERROR failed");
1982: }
1.429 djm 1983:
1.367 djm 1984: if (err == 0) {
1.429 djm 1985: /* Non-blocking connection completed */
1.367 djm 1986: debug("channel %d: connected to %s port %d",
1987: c->self, c->connect_ctx.host, c->connect_ctx.port);
1988: channel_connect_ctx_free(&c->connect_ctx);
1989: c->type = SSH_CHANNEL_OPEN;
1.426 djm 1990: c->lastused = monotime();
1.372 markus 1991: if (isopen) {
1992: /* no message necessary */
1993: } else {
1994: if ((r = sshpkt_start(ssh,
1995: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1996: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1997: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1998: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 1999: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0 ||
2000: (r = sshpkt_send(ssh)) != 0)
2001: fatal_fr(r, "channel %i open confirm", c->self);
1.367 djm 2002: }
1.429 djm 2003: return;
2004: }
2005: if (err == EINTR || err == EAGAIN || err == EINPROGRESS)
2006: return;
2007:
2008: /* Non-blocking connection failed */
2009: debug("channel %d: connection failed: %s", c->self, strerror(err));
2010:
2011: /* Try next address, if any */
2012: if ((sock = connect_next(&c->connect_ctx)) == -1) {
2013: /* Exhausted all addresses for this destination */
1.367 djm 2014: error("connect_to %.100s port %d: failed.",
2015: c->connect_ctx.host, c->connect_ctx.port);
2016: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 2017: if (isopen) {
2018: rdynamic_close(ssh, c);
2019: } else {
2020: if ((r = sshpkt_start(ssh,
2021: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
2022: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 2023: (r = sshpkt_put_u32(ssh,
2024: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
2025: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1.403 djm 2026: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2027: (r = sshpkt_send(ssh)) != 0)
2028: fatal_fr(r, "channel %i: failure", c->self);
1.372 markus 2029: chan_mark_dead(ssh, c);
1.75 markus 2030: }
2031: }
1.429 djm 2032:
2033: /* New non-blocking connection in progress */
2034: close(c->sock);
2035: c->sock = c->rfd = c->wfd = sock;
1.75 markus 2036: }
2037:
1.127 itojun 2038: static int
1.410 djm 2039: channel_handle_rfd(struct ssh *ssh, Channel *c)
1.41 markus 2040: {
1.214 markus 2041: char buf[CHAN_RBUF];
1.367 djm 2042: ssize_t len;
2043: int r;
1.426 djm 2044: size_t nr = 0, have, avail, maxlen = CHANNEL_MAX_READ;
1.25 markus 2045:
1.410 djm 2046: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.412 djm 2047: return 1; /* Shouldn't happen */
2048: if ((avail = sshbuf_avail(c->input)) == 0)
2049: return 1; /* Shouldn't happen */
2050:
2051: /*
2052: * For "simple" channels (i.e. not datagram or filtered), we can
2053: * read directly to the channel buffer.
2054: */
2055: if (c->input_filter == NULL && !c->datagram) {
2056: /* Only OPEN channels have valid rwin */
2057: if (c->type == SSH_CHANNEL_OPEN) {
2058: if ((have = sshbuf_len(c->input)) >= c->remote_window)
2059: return 1; /* shouldn't happen */
2060: if (maxlen > c->remote_window - have)
2061: maxlen = c->remote_window - have;
2062: }
2063: if (maxlen > avail)
2064: maxlen = avail;
1.426 djm 2065: if ((r = sshbuf_read(c->rfd, c->input, maxlen, &nr)) != 0) {
1.413 djm 2066: if (errno == EINTR || errno == EAGAIN)
2067: return 1;
1.412 djm 2068: debug2("channel %d: read failed rfd %d maxlen %zu: %s",
2069: c->self, c->rfd, maxlen, ssh_err(r));
2070: goto rfail;
2071: }
1.426 djm 2072: if (nr != 0)
2073: c->lastused = monotime();
1.367 djm 2074: return 1;
1.412 djm 2075: }
1.367 djm 2076:
2077: len = read(c->rfd, buf, sizeof(buf));
1.393 deraadt 2078: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2079: return 1;
2080: if (len <= 0) {
1.412 djm 2081: debug2("channel %d: read<=0 rfd %d len %zd: %s",
2082: c->self, c->rfd, len,
2083: len == 0 ? "closed" : strerror(errno));
2084: rfail:
1.367 djm 2085: if (c->type != SSH_CHANNEL_OPEN) {
2086: debug2("channel %d: not open", c->self);
2087: chan_mark_dead(ssh, c);
1.41 markus 2088: return -1;
1.65 markus 2089: } else {
1.367 djm 2090: chan_read_failed(ssh, c);
1.65 markus 2091: }
1.367 djm 2092: return -1;
2093: }
1.426 djm 2094: c->lastused = monotime();
1.367 djm 2095: if (c->input_filter != NULL) {
2096: if (c->input_filter(ssh, c, buf, len) == -1) {
2097: debug2("channel %d: filter stops", c->self);
2098: chan_read_failed(ssh, c);
2099: }
2100: } else if (c->datagram) {
2101: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1.403 djm 2102: fatal_fr(r, "channel %i: put datagram", c->self);
1.412 djm 2103: }
1.41 markus 2104: return 1;
2105: }
1.241 deraadt 2106:
1.127 itojun 2107: static int
1.410 djm 2108: channel_handle_wfd(struct ssh *ssh, Channel *c)
1.41 markus 2109: {
1.95 markus 2110: struct termios tio;
1.367 djm 2111: u_char *data = NULL, *buf; /* XXX const; need filter API change */
2112: size_t dlen, olen = 0;
2113: int r, len;
2114:
1.410 djm 2115: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
2116: return 1;
2117: if (sshbuf_len(c->output) == 0)
1.367 djm 2118: return 1;
1.25 markus 2119:
1.41 markus 2120: /* Send buffered output data to the socket. */
1.367 djm 2121: olen = sshbuf_len(c->output);
2122: if (c->output_filter != NULL) {
2123: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
2124: debug2("channel %d: filter stops", c->self);
2125: if (c->type != SSH_CHANNEL_OPEN)
2126: chan_mark_dead(ssh, c);
2127: else
2128: chan_write_failed(ssh, c);
2129: return -1;
1.231 reyk 2130: }
1.367 djm 2131: } else if (c->datagram) {
2132: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1.403 djm 2133: fatal_fr(r, "channel %i: get datagram", c->self);
1.369 djm 2134: buf = data;
1.367 djm 2135: } else {
2136: buf = data = sshbuf_mutable_ptr(c->output);
2137: dlen = sshbuf_len(c->output);
2138: }
1.231 reyk 2139:
1.367 djm 2140: if (c->datagram) {
2141: /* ignore truncated writes, datagrams might get lost */
1.374 djm 2142: len = write(c->wfd, buf, dlen);
1.367 djm 2143: free(data);
1.393 deraadt 2144: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 2145: return 1;
1.367 djm 2146: if (len <= 0)
2147: goto write_fail;
2148: goto out;
2149: }
2150:
2151: len = write(c->wfd, buf, dlen);
1.393 deraadt 2152: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2153: return 1;
2154: if (len <= 0) {
2155: write_fail:
2156: if (c->type != SSH_CHANNEL_OPEN) {
2157: debug2("channel %d: not open", c->self);
2158: chan_mark_dead(ssh, c);
1.41 markus 2159: return -1;
1.367 djm 2160: } else {
2161: chan_write_failed(ssh, c);
1.91 markus 2162: }
1.367 djm 2163: return -1;
2164: }
1.426 djm 2165: c->lastused = monotime();
1.367 djm 2166: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2167: if (tcgetattr(c->wfd, &tio) == 0 &&
2168: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2169: /*
2170: * Simulate echo to reduce the impact of
2171: * traffic analysis. We need to match the
2172: * size of a SSH2_MSG_CHANNEL_DATA message
2173: * (4 byte channel id + buf)
2174: */
2175: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2176: (r = sshpkt_send(ssh)) != 0)
1.403 djm 2177: fatal_fr(r, "channel %i: ignore", c->self);
1.25 markus 2178: }
1.367 djm 2179: }
1.403 djm 2180: if ((r = sshbuf_consume(c->output, len)) != 0)
2181: fatal_fr(r, "channel %i: consume", c->self);
1.309 djm 2182: out:
1.367 djm 2183: c->local_consumed += olen - sshbuf_len(c->output);
2184:
2185: return 1;
2186: }
2187:
2188: static int
1.410 djm 2189: channel_handle_efd_write(struct ssh *ssh, Channel *c)
1.367 djm 2190: {
2191: int r;
2192: ssize_t len;
2193:
1.410 djm 2194: if ((c->io_ready & SSH_CHAN_IO_EFD_W) == 0)
2195: return 1;
2196: if (sshbuf_len(c->extended) == 0)
1.367 djm 2197: return 1;
2198:
2199: len = write(c->efd, sshbuf_ptr(c->extended),
2200: sshbuf_len(c->extended));
2201: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 deraadt 2202: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2203: return 1;
2204: if (len <= 0) {
2205: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1.407 djm 2206: channel_close_fd(ssh, c, &c->efd);
1.367 djm 2207: } else {
1.403 djm 2208: if ((r = sshbuf_consume(c->extended, len)) != 0)
2209: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2210: c->local_consumed += len;
1.426 djm 2211: c->lastused = monotime();
1.367 djm 2212: }
1.44 markus 2213: return 1;
2214: }
1.241 deraadt 2215:
1.127 itojun 2216: static int
1.410 djm 2217: channel_handle_efd_read(struct ssh *ssh, Channel *c)
1.44 markus 2218: {
1.214 markus 2219: char buf[CHAN_RBUF];
1.367 djm 2220: int r;
2221: ssize_t len;
2222:
1.410 djm 2223: if ((c->io_ready & SSH_CHAN_IO_EFD_R) == 0)
1.367 djm 2224: return 1;
1.44 markus 2225:
1.367 djm 2226: len = read(c->efd, buf, sizeof(buf));
2227: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 deraadt 2228: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2229: return 1;
2230: if (len <= 0) {
1.403 djm 2231: debug2("channel %d: closing read-efd %d", c->self, c->efd);
1.407 djm 2232: channel_close_fd(ssh, c, &c->efd);
1.426 djm 2233: return 1;
2234: }
2235: c->lastused = monotime();
2236: if (c->extended_usage == CHAN_EXTENDED_IGNORE)
1.403 djm 2237: debug3("channel %d: discard efd", c->self);
2238: else if ((r = sshbuf_put(c->extended, buf, len)) != 0)
2239: fatal_fr(r, "channel %i: append", c->self);
1.44 markus 2240: return 1;
2241: }
1.241 deraadt 2242:
1.127 itojun 2243: static int
1.410 djm 2244: channel_handle_efd(struct ssh *ssh, Channel *c)
1.44 markus 2245: {
1.367 djm 2246: if (c->efd == -1)
2247: return 1;
2248:
2249: /** XXX handle drain efd, too */
2250:
2251: if (c->extended_usage == CHAN_EXTENDED_WRITE)
1.410 djm 2252: return channel_handle_efd_write(ssh, c);
1.367 djm 2253: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2254: c->extended_usage == CHAN_EXTENDED_IGNORE)
1.410 djm 2255: return channel_handle_efd_read(ssh, c);
1.367 djm 2256:
2257: return 1;
2258: }
2259:
2260: static int
2261: channel_check_window(struct ssh *ssh, Channel *c)
2262: {
2263: int r;
2264:
1.104 markus 2265: if (c->type == SSH_CHANNEL_OPEN &&
2266: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2267: ((c->local_window_max - c->local_window >
1.269 markus 2268: c->local_maxpacket*3) ||
2269: c->local_window < c->local_window_max/2) &&
1.44 markus 2270: c->local_consumed > 0) {
1.368 djm 2271: if (!c->have_remote_id)
1.403 djm 2272: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2273: if ((r = sshpkt_start(ssh,
2274: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2275: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2276: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2277: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2278: fatal_fr(r, "channel %i", c->self);
1.367 djm 2279: }
1.403 djm 2280: debug2("channel %d: window %d sent adjust %d", c->self,
2281: c->local_window, c->local_consumed);
1.44 markus 2282: c->local_window += c->local_consumed;
2283: c->local_consumed = 0;
1.1 deraadt 2284: }
1.41 markus 2285: return 1;
1.1 deraadt 2286: }
2287:
1.127 itojun 2288: static void
1.410 djm 2289: channel_post_open(struct ssh *ssh, Channel *c)
1.41 markus 2290: {
1.410 djm 2291: channel_handle_rfd(ssh, c);
2292: channel_handle_wfd(ssh, c);
2293: channel_handle_efd(ssh, c);
1.367 djm 2294: channel_check_window(ssh, c);
1.44 markus 2295: }
2296:
1.302 djm 2297: static u_int
1.367 djm 2298: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2299: {
2300: char buf[CHAN_RBUF];
1.367 djm 2301: ssize_t len;
1.302 djm 2302: u_int rlen;
1.367 djm 2303: int r;
1.302 djm 2304:
1.367 djm 2305: if (sshbuf_len(c->input) < need) {
2306: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2307: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 deraadt 2308: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2309: return sshbuf_len(c->input);
1.302 djm 2310: if (len <= 0) {
1.367 djm 2311: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2312: c->self, c->rfd, len);
1.367 djm 2313: chan_read_failed(ssh, c);
1.349 naddy 2314: return 0;
1.403 djm 2315: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
2316: fatal_fr(r, "channel %i: append", c->self);
1.302 djm 2317: }
1.367 djm 2318: return sshbuf_len(c->input);
1.302 djm 2319: }
2320:
2321: static void
1.410 djm 2322: channel_post_mux_client_read(struct ssh *ssh, Channel *c)
1.302 djm 2323: {
2324: u_int need;
2325:
1.410 djm 2326: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.367 djm 2327: return;
2328: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2329: return;
2330: if (c->mux_pause)
2331: return;
2332:
2333: /*
2334: * Don't not read past the precise end of packets to
2335: * avoid disrupting fd passing.
2336: */
2337: if (read_mux(ssh, c, 4) < 4) /* read header */
2338: return;
2339: /* XXX sshbuf_peek_u32 */
2340: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2341: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2342: if (need > CHANNEL_MUX_MAX_PACKET) {
2343: debug2("channel %d: packet too big %u > %u",
2344: c->self, CHANNEL_MUX_MAX_PACKET, need);
2345: chan_rcvd_oclose(ssh, c);
2346: return;
2347: }
2348: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2349: return;
2350: if (c->mux_rcb(ssh, c) != 0) {
2351: debug("channel %d: mux_rcb failed", c->self);
2352: chan_mark_dead(ssh, c);
2353: return;
1.302 djm 2354: }
1.367 djm 2355: }
2356:
2357: static void
1.410 djm 2358: channel_post_mux_client_write(struct ssh *ssh, Channel *c)
1.367 djm 2359: {
2360: ssize_t len;
2361: int r;
1.302 djm 2362:
1.410 djm 2363: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
2364: return;
2365: if (sshbuf_len(c->output) == 0)
1.367 djm 2366: return;
2367:
2368: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 deraadt 2369: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2370: return;
2371: if (len <= 0) {
2372: chan_mark_dead(ssh, c);
2373: return;
1.302 djm 2374: }
1.367 djm 2375: if ((r = sshbuf_consume(c->output, len)) != 0)
1.403 djm 2376: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2377: }
2378:
2379: static void
1.410 djm 2380: channel_post_mux_client(struct ssh *ssh, Channel *c)
1.367 djm 2381: {
1.410 djm 2382: channel_post_mux_client_read(ssh, c);
2383: channel_post_mux_client_write(ssh, c);
1.302 djm 2384: }
2385:
2386: static void
1.410 djm 2387: channel_post_mux_listener(struct ssh *ssh, Channel *c)
1.302 djm 2388: {
2389: Channel *nc;
2390: struct sockaddr_storage addr;
2391: socklen_t addrlen;
2392: int newsock;
2393: uid_t euid;
2394: gid_t egid;
2395:
1.410 djm 2396: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.302 djm 2397: return;
2398:
2399: debug("multiplexing control connection");
2400:
2401: /*
2402: * Accept connection on control socket
2403: */
2404: memset(&addr, 0, sizeof(addr));
2405: addrlen = sizeof(addr);
2406: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2407: &addrlen)) == -1) {
1.403 djm 2408: error_f("accept: %s", strerror(errno));
1.317 djm 2409: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2410: c->notbefore = monotime() + 1;
1.302 djm 2411: return;
2412: }
2413:
1.393 deraadt 2414: if (getpeereid(newsock, &euid, &egid) == -1) {
1.403 djm 2415: error_f("getpeereid failed: %s", strerror(errno));
1.302 djm 2416: close(newsock);
2417: return;
2418: }
2419: if ((euid != 0) && (getuid() != euid)) {
2420: error("multiplex uid mismatch: peer euid %u != uid %u",
2421: (u_int)euid, (u_int)getuid());
2422: close(newsock);
2423: return;
2424: }
1.424 djm 2425: nc = channel_new(ssh, "mux-control", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2426: newsock, newsock, -1, c->local_window_max,
2427: c->local_maxpacket, 0, "mux-control", 1);
2428: nc->mux_rcb = c->mux_rcb;
1.403 djm 2429: debug3_f("new mux channel %d fd %d", nc->self, nc->sock);
1.302 djm 2430: /* establish state */
1.367 djm 2431: nc->mux_rcb(ssh, nc);
1.302 djm 2432: /* mux state transitions must not elicit protocol messages */
2433: nc->flags |= CHAN_LOCAL;
2434: }
2435:
1.127 itojun 2436: static void
1.367 djm 2437: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2438: {
1.367 djm 2439: chan_fn **pre, **post;
2440:
2441: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
1.406 djm 2442: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
1.403 djm 2443: fatal_f("allocation failed");
1.367 djm 2444:
2445: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2446: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2447: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2448: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2449: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2450: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2451: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2452: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2453: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2454: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2455: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2456: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2457: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2458:
2459: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2460: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2461: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2462: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2463: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2464: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2465: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2466: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2467: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2468: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2469: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2470: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2471:
1.367 djm 2472: sc->channel_pre = pre;
2473: sc->channel_post = post;
1.44 markus 2474: }
2475:
1.140 markus 2476: /* gc dead channels */
2477: static void
1.367 djm 2478: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2479: {
2480: if (c == NULL)
2481: return;
2482: if (c->detach_user != NULL) {
1.367 djm 2483: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2484: return;
1.385 djm 2485:
1.194 markus 2486: debug2("channel %d: gc: notify user", c->self);
1.423 djm 2487: c->detach_user(ssh, c->self, 0, NULL);
1.140 markus 2488: /* if we still have a callback */
2489: if (c->detach_user != NULL)
2490: return;
1.194 markus 2491: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2492: }
1.367 djm 2493: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2494: return;
1.194 markus 2495: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2496: channel_free(ssh, c);
1.140 markus 2497: }
2498:
1.367 djm 2499: enum channel_table { CHAN_PRE, CHAN_POST };
2500:
1.127 itojun 2501: static void
1.422 djm 2502: channel_handler(struct ssh *ssh, int table, struct timespec *timeout)
1.41 markus 2503: {
1.367 djm 2504: struct ssh_channels *sc = ssh->chanctxt;
2505: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2506: u_int i, oalloc;
1.41 markus 2507: Channel *c;
1.317 djm 2508: time_t now;
1.25 markus 2509:
1.322 dtucker 2510: now = monotime();
1.367 djm 2511: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2512: c = sc->channels[i];
1.113 markus 2513: if (c == NULL)
1.41 markus 2514: continue;
1.417 djm 2515: /* Try to keep IO going while rekeying */
2516: if (ssh_packet_is_rekeying(ssh) && c->type != SSH_CHANNEL_OPEN)
2517: continue;
1.299 markus 2518: if (c->delayed) {
1.367 djm 2519: if (table == CHAN_PRE)
1.299 markus 2520: c->delayed = 0;
2521: else
2522: continue;
2523: }
1.317 djm 2524: if (ftab[c->type] != NULL) {
1.426 djm 2525: if (table == CHAN_PRE &&
2526: c->type == SSH_CHANNEL_OPEN &&
2527: c->inactive_deadline != 0 && c->lastused != 0 &&
2528: now >= c->lastused + c->inactive_deadline) {
2529: /* channel closed for inactivity */
2530: verbose("channel %d: closing after %u seconds "
2531: "of inactivity", c->self,
2532: c->inactive_deadline);
2533: channel_force_close(ssh, c, 1);
2534: } else if (c->notbefore <= now) {
2535: /* Run handlers that are not paused. */
1.410 djm 2536: (*ftab[c->type])(ssh, c);
1.426 djm 2537: /* inactivity timeouts must interrupt poll() */
2538: if (timeout != NULL &&
2539: c->type == SSH_CHANNEL_OPEN &&
2540: c->lastused != 0 &&
2541: c->inactive_deadline != 0) {
2542: ptimeout_deadline_monotime(timeout,
2543: c->lastused + c->inactive_deadline);
2544: }
2545: } else if (timeout != NULL) {
1.317 djm 2546: /*
1.426 djm 2547: * Arrange for poll() wakeup when channel pause
1.422 djm 2548: * timer expires.
1.317 djm 2549: */
1.422 djm 2550: ptimeout_deadline_monotime(timeout,
2551: c->notbefore);
1.317 djm 2552: }
2553: }
1.367 djm 2554: channel_garbage_collect(ssh, c);
1.1 deraadt 2555: }
2556: }
2557:
1.121 markus 2558: /*
1.411 djm 2559: * Create sockets before preparing IO.
1.372 markus 2560: * This is necessary for things that need to happen after reading
1.411 djm 2561: * the network-input but need to be completed before IO event setup, e.g.
2562: * because they may create new channels.
1.372 markus 2563: */
2564: static void
1.411 djm 2565: channel_before_prepare_io(struct ssh *ssh)
1.372 markus 2566: {
2567: struct ssh_channels *sc = ssh->chanctxt;
2568: Channel *c;
2569: u_int i, oalloc;
2570:
2571: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2572: c = sc->channels[i];
2573: if (c == NULL)
2574: continue;
2575: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
1.411 djm 2576: channel_before_prepare_io_rdynamic(ssh, c);
2577: }
2578: }
2579:
2580: static void
2581: dump_channel_poll(const char *func, const char *what, Channel *c,
2582: u_int pollfd_offset, struct pollfd *pfd)
2583: {
2584: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2585: debug3("%s: channel %d: %s r%d w%d e%d s%d c->pfds [ %d %d %d %d ] "
2586: "io_want 0x%02x io_ready 0x%02x pfd[%u].fd=%d "
2587: "pfd.ev 0x%02x pfd.rev 0x%02x", func, c->self, what,
2588: c->rfd, c->wfd, c->efd, c->sock,
2589: c->pfds[0], c->pfds[1], c->pfds[2], c->pfds[3],
2590: c->io_want, c->io_ready,
2591: pollfd_offset, pfd->fd, pfd->events, pfd->revents);
1.411 djm 2592: #endif
2593: }
2594:
2595: /* Prepare pollfd entries for a single channel */
2596: static void
2597: channel_prepare_pollfd(Channel *c, u_int *next_pollfd,
2598: struct pollfd *pfd, u_int npfd)
2599: {
1.415 djm 2600: u_int ev, p = *next_pollfd;
1.411 djm 2601:
2602: if (c == NULL)
2603: return;
2604: if (p + 4 > npfd) {
2605: /* Shouldn't happen */
2606: fatal_f("channel %d: bad pfd offset %u (max %u)",
2607: c->self, p, npfd);
2608: }
1.415 djm 2609: c->pfds[0] = c->pfds[1] = c->pfds[2] = c->pfds[3] = -1;
1.411 djm 2610: /*
2611: * prepare c->rfd
2612: *
2613: * This is a special case, since c->rfd might be the same as
2614: * c->wfd, c->efd and/or c->sock. Handle those here if they want
2615: * IO too.
2616: */
2617: if (c->rfd != -1) {
1.415 djm 2618: ev = 0;
1.411 djm 2619: if ((c->io_want & SSH_CHAN_IO_RFD) != 0)
1.415 djm 2620: ev |= POLLIN;
1.411 djm 2621: /* rfd == wfd */
1.415 djm 2622: if (c->wfd == c->rfd) {
2623: if ((c->io_want & SSH_CHAN_IO_WFD) != 0)
2624: ev |= POLLOUT;
2625: }
1.411 djm 2626: /* rfd == efd */
1.415 djm 2627: if (c->efd == c->rfd) {
2628: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
2629: ev |= POLLIN;
2630: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
2631: ev |= POLLOUT;
2632: }
1.411 djm 2633: /* rfd == sock */
1.415 djm 2634: if (c->sock == c->rfd) {
2635: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
2636: ev |= POLLIN;
2637: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
2638: ev |= POLLOUT;
2639: }
2640: /* Pack a pfd entry if any event armed for this fd */
2641: if (ev != 0) {
2642: c->pfds[0] = p;
2643: pfd[p].fd = c->rfd;
2644: pfd[p].events = ev;
2645: dump_channel_poll(__func__, "rfd", c, p, &pfd[p]);
2646: p++;
2647: }
1.411 djm 2648: }
1.415 djm 2649: /* prepare c->wfd if wanting IO and not already handled above */
1.411 djm 2650: if (c->wfd != -1 && c->rfd != c->wfd) {
1.415 djm 2651: ev = 0;
2652: if ((c->io_want & SSH_CHAN_IO_WFD))
2653: ev |= POLLOUT;
2654: /* Pack a pfd entry if any event armed for this fd */
2655: if (ev != 0) {
2656: c->pfds[1] = p;
2657: pfd[p].fd = c->wfd;
2658: pfd[p].events = ev;
2659: dump_channel_poll(__func__, "wfd", c, p, &pfd[p]);
2660: p++;
2661: }
1.411 djm 2662: }
1.415 djm 2663: /* prepare c->efd if wanting IO and not already handled above */
1.411 djm 2664: if (c->efd != -1 && c->rfd != c->efd) {
1.415 djm 2665: ev = 0;
1.411 djm 2666: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
1.415 djm 2667: ev |= POLLIN;
1.411 djm 2668: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
1.415 djm 2669: ev |= POLLOUT;
2670: /* Pack a pfd entry if any event armed for this fd */
2671: if (ev != 0) {
2672: c->pfds[2] = p;
2673: pfd[p].fd = c->efd;
2674: pfd[p].events = ev;
2675: dump_channel_poll(__func__, "efd", c, p, &pfd[p]);
2676: p++;
2677: }
1.411 djm 2678: }
1.415 djm 2679: /* prepare c->sock if wanting IO and not already handled above */
1.411 djm 2680: if (c->sock != -1 && c->rfd != c->sock) {
1.415 djm 2681: ev = 0;
1.411 djm 2682: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
1.415 djm 2683: ev |= POLLIN;
1.411 djm 2684: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
1.415 djm 2685: ev |= POLLOUT;
2686: /* Pack a pfd entry if any event armed for this fd */
2687: if (ev != 0) {
2688: c->pfds[3] = p;
2689: pfd[p].fd = c->sock;
2690: pfd[p].events = 0;
2691: dump_channel_poll(__func__, "sock", c, p, &pfd[p]);
2692: p++;
2693: }
1.372 markus 2694: }
1.411 djm 2695: *next_pollfd = p;
1.372 markus 2696: }
2697:
1.411 djm 2698: /* * Allocate/prepare poll structure */
1.49 markus 2699: void
1.411 djm 2700: channel_prepare_poll(struct ssh *ssh, struct pollfd **pfdp, u_int *npfd_allocp,
1.422 djm 2701: u_int *npfd_activep, u_int npfd_reserved, struct timespec *timeout)
1.41 markus 2702: {
1.410 djm 2703: struct ssh_channels *sc = ssh->chanctxt;
1.411 djm 2704: u_int i, oalloc, p, npfd = npfd_reserved;
2705:
2706: channel_before_prepare_io(ssh); /* might create a new channel */
1.416 djm 2707: /* clear out I/O flags from last poll */
2708: for (i = 0; i < sc->channels_alloc; i++) {
2709: if (sc->channels[i] == NULL)
2710: continue;
2711: sc->channels[i]->io_want = sc->channels[i]->io_ready = 0;
2712: }
1.411 djm 2713: /* Allocate 4x pollfd for each channel (rfd, wfd, efd, sock) */
2714: if (sc->channels_alloc >= (INT_MAX / 4) - npfd_reserved)
2715: fatal_f("too many channels"); /* shouldn't happen */
1.417 djm 2716: npfd += sc->channels_alloc * 4;
1.411 djm 2717: if (npfd > *npfd_allocp) {
2718: *pfdp = xrecallocarray(*pfdp, *npfd_allocp,
2719: npfd, sizeof(**pfdp));
2720: *npfd_allocp = npfd;
2721: }
2722: *npfd_activep = npfd_reserved;
2723: oalloc = sc->channels_alloc;
1.372 markus 2724:
1.422 djm 2725: channel_handler(ssh, CHAN_PRE, timeout);
1.84 markus 2726:
1.411 djm 2727: if (oalloc != sc->channels_alloc) {
2728: /* shouldn't happen */
2729: fatal_f("channels_alloc changed during CHAN_PRE "
2730: "(was %u, now %u)", oalloc, sc->channels_alloc);
2731: }
1.84 markus 2732:
1.411 djm 2733: /* Prepare pollfd */
2734: p = npfd_reserved;
2735: for (i = 0; i < sc->channels_alloc; i++)
2736: channel_prepare_pollfd(sc->channels[i], &p, *pfdp, npfd);
2737: *npfd_activep = p;
2738: }
2739:
2740: static void
1.415 djm 2741: fd_ready(Channel *c, int p, struct pollfd *pfds, u_int npfd, int fd,
1.411 djm 2742: const char *what, u_int revents_mask, u_int ready)
2743: {
2744: struct pollfd *pfd = &pfds[p];
1.410 djm 2745:
1.411 djm 2746: if (fd == -1)
2747: return;
1.415 djm 2748: if (p == -1 || (u_int)p >= npfd)
2749: fatal_f("channel %d: bad pfd %d (max %u)", c->self, p, npfd);
1.411 djm 2750: dump_channel_poll(__func__, what, c, p, pfd);
2751: if (pfd->fd != fd) {
2752: fatal("channel %d: inconsistent %s fd=%d pollfd[%u].fd %d "
2753: "r%d w%d e%d s%d", c->self, what, fd, p, pfd->fd,
2754: c->rfd, c->wfd, c->efd, c->sock);
2755: }
2756: if ((pfd->revents & POLLNVAL) != 0) {
2757: fatal("channel %d: invalid %s pollfd[%u].fd %d r%d w%d e%d s%d",
2758: c->self, what, p, pfd->fd, c->rfd, c->wfd, c->efd, c->sock);
1.410 djm 2759: }
1.411 djm 2760: if ((pfd->revents & (revents_mask|POLLHUP|POLLERR)) != 0)
2761: c->io_ready |= ready & c->io_want;
1.41 markus 2762: }
2763:
1.121 markus 2764: /*
1.411 djm 2765: * After poll, perform any appropriate operations for channels which have
1.121 markus 2766: * events pending.
2767: */
1.49 markus 2768: void
1.411 djm 2769: channel_after_poll(struct ssh *ssh, struct pollfd *pfd, u_int npfd)
1.41 markus 2770: {
1.410 djm 2771: struct ssh_channels *sc = ssh->chanctxt;
1.415 djm 2772: u_int i;
2773: int p;
1.410 djm 2774: Channel *c;
2775:
1.411 djm 2776: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2777: for (p = 0; p < (int)npfd; p++) {
1.411 djm 2778: if (pfd[p].revents == 0)
2779: continue;
2780: debug_f("pfd[%u].fd %d rev 0x%04x",
2781: p, pfd[p].fd, pfd[p].revents);
2782: }
2783: #endif
2784:
2785: /* Convert pollfd into c->io_ready */
2786: for (i = 0; i < sc->channels_alloc; i++) {
1.410 djm 2787: c = sc->channels[i];
1.415 djm 2788: if (c == NULL)
1.410 djm 2789: continue;
1.411 djm 2790: /* if rfd is shared with efd/sock then wfd should be too */
2791: if (c->rfd != -1 && c->wfd != -1 && c->rfd != c->wfd &&
2792: (c->rfd == c->efd || c->rfd == c->sock)) {
2793: /* Shouldn't happen */
2794: fatal_f("channel %d: unexpected fds r%d w%d e%d s%d",
2795: c->self, c->rfd, c->wfd, c->efd, c->sock);
2796: }
1.410 djm 2797: c->io_ready = 0;
1.411 djm 2798: /* rfd, potentially shared with wfd, efd and sock */
1.415 djm 2799: if (c->rfd != -1 && (p = c->pfds[0]) != -1) {
2800: fd_ready(c, p, pfd, npfd, c->rfd,
2801: "rfd", POLLIN, SSH_CHAN_IO_RFD);
1.411 djm 2802: if (c->rfd == c->wfd) {
1.415 djm 2803: fd_ready(c, p, pfd, npfd, c->wfd,
2804: "wfd/r", POLLOUT, SSH_CHAN_IO_WFD);
1.411 djm 2805: }
2806: if (c->rfd == c->efd) {
1.415 djm 2807: fd_ready(c, p, pfd, npfd, c->efd,
2808: "efdr/r", POLLIN, SSH_CHAN_IO_EFD_R);
2809: fd_ready(c, p, pfd, npfd, c->efd,
2810: "efdw/r", POLLOUT, SSH_CHAN_IO_EFD_W);
1.411 djm 2811: }
2812: if (c->rfd == c->sock) {
1.415 djm 2813: fd_ready(c, p, pfd, npfd, c->sock,
2814: "sockr/r", POLLIN, SSH_CHAN_IO_SOCK_R);
2815: fd_ready(c, p, pfd, npfd, c->sock,
2816: "sockw/r", POLLOUT, SSH_CHAN_IO_SOCK_W);
1.411 djm 2817: }
1.415 djm 2818: dump_channel_poll(__func__, "rfd", c, p, pfd);
1.411 djm 2819: }
2820: /* wfd */
1.415 djm 2821: if (c->wfd != -1 && c->wfd != c->rfd &&
2822: (p = c->pfds[1]) != -1) {
2823: fd_ready(c, p, pfd, npfd, c->wfd,
2824: "wfd", POLLOUT, SSH_CHAN_IO_WFD);
2825: dump_channel_poll(__func__, "wfd", c, p, pfd);
1.411 djm 2826: }
2827: /* efd */
1.415 djm 2828: if (c->efd != -1 && c->efd != c->rfd &&
2829: (p = c->pfds[2]) != -1) {
2830: fd_ready(c, p, pfd, npfd, c->efd,
2831: "efdr", POLLIN, SSH_CHAN_IO_EFD_R);
2832: fd_ready(c, p, pfd, npfd, c->efd,
2833: "efdw", POLLOUT, SSH_CHAN_IO_EFD_W);
2834: dump_channel_poll(__func__, "efd", c, p, pfd);
1.411 djm 2835: }
2836: /* sock */
1.415 djm 2837: if (c->sock != -1 && c->sock != c->rfd &&
2838: (p = c->pfds[3]) != -1) {
2839: fd_ready(c, p, pfd, npfd, c->sock,
2840: "sockr", POLLIN, SSH_CHAN_IO_SOCK_R);
2841: fd_ready(c, p, pfd, npfd, c->sock,
2842: "sockw", POLLOUT, SSH_CHAN_IO_SOCK_W);
2843: dump_channel_poll(__func__, "sock", c, p, pfd);
1.411 djm 2844: }
1.410 djm 2845: }
2846: channel_handler(ssh, CHAN_POST, NULL);
1.367 djm 2847: }
2848:
2849: /*
2850: * Enqueue data for channels with open or draining c->input.
2851: */
2852: static void
2853: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2854: {
1.373 djm 2855: size_t len, plen;
2856: const u_char *pkt;
1.367 djm 2857: int r;
2858:
2859: if ((len = sshbuf_len(c->input)) == 0) {
2860: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2861: /*
2862: * input-buffer is empty and read-socket shutdown:
2863: * tell peer, that we will not send more data:
2864: * send IEOF.
2865: * hack for extended data: delay EOF if EFD still
2866: * in use.
2867: */
2868: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2869: debug2("channel %d: "
2870: "ibuf_empty delayed efd %d/(%zu)",
2871: c->self, c->efd, sshbuf_len(c->extended));
2872: else
2873: chan_ibuf_empty(ssh, c);
2874: }
2875: return;
2876: }
2877:
1.368 djm 2878: if (!c->have_remote_id)
1.403 djm 2879: fatal_f("channel %d: no remote id", c->self);
1.368 djm 2880:
1.367 djm 2881: if (c->datagram) {
2882: /* Check datagram will fit; drop if not */
1.373 djm 2883: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
1.403 djm 2884: fatal_fr(r, "channel %i: get datagram", c->self);
1.367 djm 2885: /*
2886: * XXX this does tail-drop on the datagram queue which is
2887: * usually suboptimal compared to head-drop. Better to have
2888: * backpressure at read time? (i.e. read + discard)
2889: */
1.373 djm 2890: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2891: debug("channel %d: datagram too big", c->self);
2892: return;
2893: }
2894: /* Enqueue it */
2895: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2896: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2897: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.403 djm 2898: (r = sshpkt_send(ssh)) != 0)
2899: fatal_fr(r, "channel %i: send datagram", c->self);
1.373 djm 2900: c->remote_window -= plen;
1.367 djm 2901: return;
2902: }
2903:
2904: /* Enqueue packet for buffered data. */
2905: if (len > c->remote_window)
2906: len = c->remote_window;
2907: if (len > c->remote_maxpacket)
2908: len = c->remote_maxpacket;
2909: if (len == 0)
2910: return;
2911: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2912: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2913: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
1.403 djm 2914: (r = sshpkt_send(ssh)) != 0)
2915: fatal_fr(r, "channel %i: send data", c->self);
1.367 djm 2916: if ((r = sshbuf_consume(c->input, len)) != 0)
1.403 djm 2917: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2918: c->remote_window -= len;
1.41 markus 2919: }
2920:
1.367 djm 2921: /*
2922: * Enqueue data for channels with open c->extended in read mode.
2923: */
2924: static void
2925: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2926: {
2927: size_t len;
2928: int r;
2929:
2930: if ((len = sshbuf_len(c->extended)) == 0)
2931: return;
2932:
2933: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2934: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2935: if (len > c->remote_window)
2936: len = c->remote_window;
2937: if (len > c->remote_maxpacket)
2938: len = c->remote_maxpacket;
2939: if (len == 0)
2940: return;
1.368 djm 2941: if (!c->have_remote_id)
1.403 djm 2942: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2943: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2944: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2945: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2946: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
1.403 djm 2947: (r = sshpkt_send(ssh)) != 0)
2948: fatal_fr(r, "channel %i: data", c->self);
1.367 djm 2949: if ((r = sshbuf_consume(c->extended, len)) != 0)
1.403 djm 2950: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2951: c->remote_window -= len;
2952: debug2("channel %d: sent ext data %zu", c->self, len);
2953: }
1.121 markus 2954:
1.84 markus 2955: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2956: void
1.367 djm 2957: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2958: {
1.367 djm 2959: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2960: Channel *c;
1.367 djm 2961: u_int i;
1.1 deraadt 2962:
1.367 djm 2963: for (i = 0; i < sc->channels_alloc; i++) {
2964: c = sc->channels[i];
1.113 markus 2965: if (c == NULL)
2966: continue;
1.37 markus 2967:
1.121 markus 2968: /*
2969: * We are only interested in channels that can have buffered
2970: * incoming data.
2971: */
1.358 djm 2972: if (c->type != SSH_CHANNEL_OPEN)
2973: continue;
2974: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2975: /* XXX is this true? */
1.367 djm 2976: debug3("channel %d: will not send data after close",
2977: c->self);
1.44 markus 2978: continue;
2979: }
1.25 markus 2980:
2981: /* Get the amount of buffered data for this channel. */
1.367 djm 2982: if (c->istate == CHAN_INPUT_OPEN ||
2983: c->istate == CHAN_INPUT_WAIT_DRAIN)
2984: channel_output_poll_input_open(ssh, c);
1.44 markus 2985: /* Send extended data, i.e. stderr */
1.358 djm 2986: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2987: c->extended_usage == CHAN_EXTENDED_READ)
2988: channel_output_poll_extended_read(ssh, c);
1.25 markus 2989: }
1.1 deraadt 2990: }
2991:
1.354 markus 2992: /* -- mux proxy support */
2993:
2994: /*
2995: * When multiplexing channel messages for mux clients we have to deal
2996: * with downstream messages from the mux client and upstream messages
2997: * from the ssh server:
2998: * 1) Handling downstream messages is straightforward and happens
2999: * in channel_proxy_downstream():
3000: * - We forward all messages (mostly) unmodified to the server.
3001: * - However, in order to route messages from upstream to the correct
3002: * downstream client, we have to replace the channel IDs used by the
3003: * mux clients with a unique channel ID because the mux clients might
3004: * use conflicting channel IDs.
3005: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
3006: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
3007: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
3008: * with the newly allocated channel ID.
3009: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 3010: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 3011: * is then translated back to the original mux client ID.
3012: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
3013: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
3014: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
3015: * downstream mux client are removed.
3016: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
3017: * requires more work, because they are not addressed to a specific
3018: * channel. E.g. client_request_forwarded_tcpip() needs to figure
3019: * out whether the request is addressed to the local client or a
3020: * specific downstream client based on the listen-address/port.
1.380 djm 3021: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 3022: * not supported as the matching session/channel cannot be identified
3023: * easily.
3024: */
3025:
3026: /*
3027: * receive packets from downstream mux clients:
3028: * channel callback fired on read from mux client, creates
3029: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
3030: * on channel creation.
3031: */
3032: int
1.367 djm 3033: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 3034: {
3035: Channel *c = NULL;
3036: struct sshbuf *original = NULL, *modified = NULL;
3037: const u_char *cp;
3038: char *ctype = NULL, *listen_host = NULL;
3039: u_char type;
3040: size_t have;
1.370 djm 3041: int ret = -1, r;
1.355 djm 3042: u_int id, remote_id, listen_port;
1.354 markus 3043:
1.367 djm 3044: /* sshbuf_dump(downstream->input, stderr); */
3045: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 3046: != 0) {
1.403 djm 3047: error_fr(r, "parse");
1.354 markus 3048: return -1;
3049: }
3050: if (have < 2) {
1.403 djm 3051: error_f("short message");
1.354 markus 3052: return -1;
3053: }
3054: type = cp[1];
3055: /* skip padlen + type */
3056: cp += 2;
3057: have -= 2;
3058: if (ssh_packet_log_type(type))
1.403 djm 3059: debug3_f("channel %u: down->up: type %u",
1.354 markus 3060: downstream->self, type);
3061:
3062: switch (type) {
3063: case SSH2_MSG_CHANNEL_OPEN:
3064: if ((original = sshbuf_from(cp, have)) == NULL ||
3065: (modified = sshbuf_new()) == NULL) {
1.403 djm 3066: error_f("alloc");
1.354 markus 3067: goto out;
3068: }
3069: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
3070: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 3071: error_fr(r, "parse");
1.354 markus 3072: goto out;
3073: }
1.424 djm 3074: c = channel_new(ssh, "mux-proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 3075: -1, -1, -1, 0, 0, 0, ctype, 1);
1.354 markus 3076: c->mux_ctx = downstream; /* point to mux client */
3077: c->mux_downstream_id = id; /* original downstream id */
3078: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
3079: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
3080: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 3081: error_fr(r, "compose");
1.367 djm 3082: channel_free(ssh, c);
1.354 markus 3083: goto out;
3084: }
3085: break;
3086: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3087: /*
3088: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
3089: * need to parse 'remote_id' instead of 'ctype'.
3090: */
3091: if ((original = sshbuf_from(cp, have)) == NULL ||
3092: (modified = sshbuf_new()) == NULL) {
1.403 djm 3093: error_f("alloc");
1.354 markus 3094: goto out;
3095: }
3096: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
3097: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 3098: error_fr(r, "parse");
1.354 markus 3099: goto out;
3100: }
1.424 djm 3101: c = channel_new(ssh, "mux-proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 3102: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
1.354 markus 3103: c->mux_ctx = downstream; /* point to mux client */
3104: c->mux_downstream_id = id;
3105: c->remote_id = remote_id;
1.368 djm 3106: c->have_remote_id = 1;
1.354 markus 3107: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
3108: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
3109: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 3110: error_fr(r, "compose");
1.367 djm 3111: channel_free(ssh, c);
1.354 markus 3112: goto out;
3113: }
3114: break;
3115: case SSH2_MSG_GLOBAL_REQUEST:
3116: if ((original = sshbuf_from(cp, have)) == NULL) {
1.403 djm 3117: error_f("alloc");
1.354 markus 3118: goto out;
3119: }
3120: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
1.403 djm 3121: error_fr(r, "parse");
1.354 markus 3122: goto out;
3123: }
3124: if (strcmp(ctype, "tcpip-forward") != 0) {
1.403 djm 3125: error_f("unsupported request %s", ctype);
1.354 markus 3126: goto out;
3127: }
3128: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
3129: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
3130: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
1.403 djm 3131: error_fr(r, "parse");
1.354 markus 3132: goto out;
3133: }
1.355 djm 3134: if (listen_port > 65535) {
1.403 djm 3135: error_f("tcpip-forward for %s: bad port %u",
3136: listen_host, listen_port);
1.355 djm 3137: goto out;
3138: }
1.354 markus 3139: /* Record that connection to this host/port is permitted. */
1.381 djm 3140: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 3141: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 3142: listen_host = NULL;
3143: break;
3144: case SSH2_MSG_CHANNEL_CLOSE:
3145: if (have < 4)
3146: break;
3147: remote_id = PEEK_U32(cp);
1.367 djm 3148: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 3149: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 3150: channel_free(ssh, c);
1.354 markus 3151: else
3152: c->flags |= CHAN_CLOSE_SENT;
3153: }
3154: break;
3155: }
3156: if (modified) {
3157: if ((r = sshpkt_start(ssh, type)) != 0 ||
3158: (r = sshpkt_putb(ssh, modified)) != 0 ||
3159: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3160: error_fr(r, "send");
1.354 markus 3161: goto out;
3162: }
3163: } else {
3164: if ((r = sshpkt_start(ssh, type)) != 0 ||
3165: (r = sshpkt_put(ssh, cp, have)) != 0 ||
3166: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3167: error_fr(r, "send");
1.354 markus 3168: goto out;
3169: }
3170: }
3171: ret = 0;
3172: out:
3173: free(ctype);
3174: free(listen_host);
3175: sshbuf_free(original);
3176: sshbuf_free(modified);
3177: return ret;
3178: }
3179:
3180: /*
3181: * receive packets from upstream server and de-multiplex packets
3182: * to correct downstream:
3183: * implemented as a helper for channel input handlers,
3184: * replaces local (proxy) channel ID with downstream channel ID.
3185: */
3186: int
1.363 markus 3187: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 3188: {
3189: struct sshbuf *b = NULL;
3190: Channel *downstream;
3191: const u_char *cp = NULL;
3192: size_t len;
3193: int r;
3194:
3195: /*
3196: * When receiving packets from the peer we need to check whether we
3197: * need to forward the packets to the mux client. In this case we
1.380 djm 3198: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 3199: * so we can cleanup the channel.
3200: */
3201: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
3202: return 0;
3203: if ((downstream = c->mux_ctx) == NULL)
3204: return 0;
3205: switch (type) {
3206: case SSH2_MSG_CHANNEL_CLOSE:
3207: case SSH2_MSG_CHANNEL_DATA:
3208: case SSH2_MSG_CHANNEL_EOF:
3209: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
3210: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3211: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
3212: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
3213: case SSH2_MSG_CHANNEL_SUCCESS:
3214: case SSH2_MSG_CHANNEL_FAILURE:
3215: case SSH2_MSG_CHANNEL_REQUEST:
3216: break;
3217: default:
1.403 djm 3218: debug2_f("channel %u: unsupported type %u", c->self, type);
1.354 markus 3219: return 0;
3220: }
3221: if ((b = sshbuf_new()) == NULL) {
1.403 djm 3222: error_f("alloc reply");
1.354 markus 3223: goto out;
3224: }
3225: /* get remaining payload (after id) */
3226: cp = sshpkt_ptr(ssh, &len);
3227: if (cp == NULL) {
1.403 djm 3228: error_f("no packet");
1.354 markus 3229: goto out;
3230: }
3231: /* translate id and send to muxclient */
3232: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
3233: (r = sshbuf_put_u8(b, type)) != 0 ||
3234: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
3235: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 3236: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.403 djm 3237: error_fr(r, "compose muxclient");
1.354 markus 3238: goto out;
3239: }
3240: /* sshbuf_dump(b, stderr); */
3241: if (ssh_packet_log_type(type))
1.403 djm 3242: debug3_f("channel %u: up->down: type %u", c->self, type);
1.354 markus 3243: out:
3244: /* update state */
3245: switch (type) {
3246: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3247: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 3248: if (cp && len > 4) {
1.354 markus 3249: c->remote_id = PEEK_U32(cp);
1.368 djm 3250: c->have_remote_id = 1;
3251: }
1.354 markus 3252: break;
3253: case SSH2_MSG_CHANNEL_CLOSE:
3254: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 3255: channel_free(ssh, c);
1.354 markus 3256: else
3257: c->flags |= CHAN_CLOSE_RCVD;
3258: break;
3259: }
3260: sshbuf_free(b);
3261: return 1;
3262: }
1.121 markus 3263:
3264: /* -- protocol input */
1.249 djm 3265:
1.367 djm 3266: /* Parse a channel ID from the current packet */
3267: static int
3268: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
3269: {
3270: u_int32_t id;
3271: int r;
3272:
3273: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
1.403 djm 3274: error_r(r, "%s: parse id", where);
1.367 djm 3275: ssh_packet_disconnect(ssh, "Invalid %s message", what);
3276: }
3277: if (id > INT_MAX) {
1.403 djm 3278: error_r(r, "%s: bad channel id %u", where, id);
1.367 djm 3279: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
3280: }
3281: return (int)id;
3282: }
3283:
3284: /* Lookup a channel from an ID in the current packet */
3285: static Channel *
3286: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
3287: {
3288: int id = channel_parse_id(ssh, where, what);
3289: Channel *c;
3290:
3291: if ((c = channel_lookup(ssh, id)) == NULL) {
3292: ssh_packet_disconnect(ssh,
3293: "%s packet referred to nonexistent channel %d", what, id);
3294: }
3295: return c;
3296: }
3297:
1.339 markus 3298: int
1.363 markus 3299: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3300: {
1.332 djm 3301: const u_char *data;
1.367 djm 3302: size_t data_len, win_len;
3303: Channel *c = channel_from_packet_id(ssh, __func__, "data");
3304: int r;
1.25 markus 3305:
1.363 markus 3306: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3307: return 0;
1.25 markus 3308:
3309: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 3310: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 3311: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
3312: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 3313: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 3314: return 0;
1.37 markus 3315:
1.25 markus 3316: /* Get the data. */
1.389 djm 3317: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3318: (r = sshpkt_get_end(ssh)) != 0)
1.403 djm 3319: fatal_fr(r, "channel %i: get data", c->self);
1.367 djm 3320:
1.309 djm 3321: win_len = data_len;
3322: if (c->datagram)
3323: win_len += 4; /* string length header */
1.200 markus 3324:
3325: /*
1.367 djm 3326: * The sending side reduces its window as it sends data, so we
3327: * must 'fake' consumption of the data in order to ensure that window
3328: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 3329: */
1.358 djm 3330: if (c->ostate != CHAN_OUTPUT_OPEN) {
3331: c->local_window -= win_len;
3332: c->local_consumed += win_len;
1.339 markus 3333: return 0;
1.200 markus 3334: }
1.41 markus 3335:
1.358 djm 3336: if (win_len > c->local_maxpacket) {
1.367 djm 3337: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 3338: c->self, win_len, c->local_maxpacket);
1.367 djm 3339: return 0;
1.358 djm 3340: }
3341: if (win_len > c->local_window) {
1.367 djm 3342: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 3343: c->self, win_len, c->local_window);
3344: return 0;
1.44 markus 3345: }
1.358 djm 3346: c->local_window -= win_len;
3347:
1.367 djm 3348: if (c->datagram) {
3349: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
1.403 djm 3350: fatal_fr(r, "channel %i: append datagram", c->self);
1.367 djm 3351: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
1.403 djm 3352: fatal_fr(r, "channel %i: append data", c->self);
1.367 djm 3353:
1.339 markus 3354: return 0;
1.1 deraadt 3355: }
1.121 markus 3356:
1.339 markus 3357: int
1.363 markus 3358: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 3359: {
1.367 djm 3360: const u_char *data;
3361: size_t data_len;
3362: u_int32_t tcode;
3363: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
3364: int r;
1.44 markus 3365:
1.363 markus 3366: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3367: return 0;
1.44 markus 3368: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 3369: logit("channel %d: ext data for non open", c->self);
1.339 markus 3370: return 0;
1.172 markus 3371: }
3372: if (c->flags & CHAN_EOF_RCVD) {
1.404 djm 3373: if (ssh->compat & SSH_BUG_EXTEOF)
1.367 djm 3374: debug("channel %d: accepting ext data after eof",
3375: c->self);
1.172 markus 3376: else
1.367 djm 3377: ssh_packet_disconnect(ssh, "Received extended_data "
3378: "after EOF on channel %d.", c->self);
3379: }
3380:
3381: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
1.403 djm 3382: error_fr(r, "parse tcode");
1.367 djm 3383: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3384: }
3385: if (c->efd == -1 ||
3386: c->extended_usage != CHAN_EXTENDED_WRITE ||
3387: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3388: logit("channel %d: bad ext data", c->self);
1.339 markus 3389: return 0;
1.44 markus 3390: }
1.389 djm 3391: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3392: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3393: error_fr(r, "parse data");
1.367 djm 3394: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3395: }
3396:
1.44 markus 3397: if (data_len > c->local_window) {
1.367 djm 3398: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3399: c->self, data_len, c->local_window);
1.339 markus 3400: return 0;
1.44 markus 3401: }
1.367 djm 3402: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3403: /* XXX sshpkt_getb? */
3404: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
1.403 djm 3405: error_fr(r, "append");
1.44 markus 3406: c->local_window -= data_len;
1.339 markus 3407: return 0;
1.44 markus 3408: }
3409:
1.339 markus 3410: int
1.363 markus 3411: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3412: {
1.367 djm 3413: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3414: int r;
1.367 djm 3415:
1.389 djm 3416: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3417: error_fr(r, "parse data");
1.389 djm 3418: ssh_packet_disconnect(ssh, "Invalid ieof message");
3419: }
1.41 markus 3420:
1.363 markus 3421: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3422: return 0;
1.367 djm 3423: chan_rcvd_ieof(ssh, c);
1.133 markus 3424:
3425: /* XXX force input close */
1.156 markus 3426: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3427: debug("channel %d: FORCE input drain", c->self);
3428: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3429: if (sshbuf_len(c->input) == 0)
3430: chan_ibuf_empty(ssh, c);
1.133 markus 3431: }
1.339 markus 3432: return 0;
1.41 markus 3433: }
1.1 deraadt 3434:
1.339 markus 3435: int
1.363 markus 3436: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3437: {
1.367 djm 3438: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3439: int r;
1.151 markus 3440:
1.363 markus 3441: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3442: return 0;
1.389 djm 3443: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3444: error_fr(r, "parse data");
1.389 djm 3445: ssh_packet_disconnect(ssh, "Invalid oclose message");
3446: }
1.367 djm 3447: chan_rcvd_oclose(ssh, c);
1.339 markus 3448: return 0;
1.1 deraadt 3449: }
3450:
1.339 markus 3451: int
1.363 markus 3452: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3453: {
1.367 djm 3454: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3455: u_int32_t remote_window, remote_maxpacket;
3456: int r;
1.25 markus 3457:
1.363 markus 3458: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3459: return 0;
3460: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3461: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3462: "non-opening channel %d.", c->self);
3463: /*
3464: * Record the remote channel number and mark that the channel
3465: * is now open.
3466: */
1.368 djm 3467: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3468: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3469: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3470: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3471: error_fr(r, "window/maxpacket");
1.389 djm 3472: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3473: }
3474:
1.368 djm 3475: c->have_remote_id = 1;
1.367 djm 3476: c->remote_window = remote_window;
3477: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3478: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3479: if (c->open_confirm) {
1.403 djm 3480: debug2_f("channel %d: callback start", c->self);
1.367 djm 3481: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
1.403 djm 3482: debug2_f("channel %d: callback done", c->self);
1.44 markus 3483: }
1.426 djm 3484: c->lastused = monotime();
1.358 djm 3485: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3486: c->remote_window, c->remote_maxpacket);
1.339 markus 3487: return 0;
1.1 deraadt 3488: }
3489:
1.127 itojun 3490: static char *
1.114 markus 3491: reason2txt(int reason)
3492: {
1.143 deraadt 3493: switch (reason) {
1.114 markus 3494: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3495: return "administratively prohibited";
3496: case SSH2_OPEN_CONNECT_FAILED:
3497: return "connect failed";
3498: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3499: return "unknown channel type";
3500: case SSH2_OPEN_RESOURCE_SHORTAGE:
3501: return "resource shortage";
3502: }
1.117 stevesk 3503: return "unknown reason";
1.114 markus 3504: }
3505:
1.339 markus 3506: int
1.363 markus 3507: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3508: {
1.367 djm 3509: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3510: u_int32_t reason;
3511: char *msg = NULL;
3512: int r;
1.25 markus 3513:
1.363 markus 3514: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3515: return 0;
3516: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3517: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3518: "non-opening channel %d.", c->self);
3519: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
1.403 djm 3520: error_fr(r, "parse reason");
1.389 djm 3521: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3522: }
1.378 djm 3523: /* skip language */
3524: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3525: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3526: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3527: error_fr(r, "parse msg/lang");
1.389 djm 3528: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3529: }
1.367 djm 3530: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3531: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3532: free(msg);
3533: if (c->open_confirm) {
1.403 djm 3534: debug2_f("channel %d: callback start", c->self);
1.367 djm 3535: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
1.403 djm 3536: debug2_f("channel %d: callback done", c->self);
1.44 markus 3537: }
1.291 djm 3538: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3539: chan_mark_dead(ssh, c);
1.339 markus 3540: return 0;
1.44 markus 3541: }
3542:
1.339 markus 3543: int
1.363 markus 3544: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3545: {
1.367 djm 3546: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3547: Channel *c;
1.367 djm 3548: u_int32_t adjust;
3549: u_int new_rwin;
3550: int r;
1.1 deraadt 3551:
1.367 djm 3552: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3553: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3554: return 0;
1.372 markus 3555: }
1.367 djm 3556:
1.363 markus 3557: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3558: return 0;
1.389 djm 3559: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3560: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3561: error_fr(r, "parse adjust");
1.389 djm 3562: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3563: }
3564: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3565: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3566: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3567: c->self, adjust, c->remote_window);
3568: }
3569: c->remote_window = new_rwin;
1.339 markus 3570: return 0;
1.121 markus 3571: }
1.1 deraadt 3572:
1.339 markus 3573: int
1.363 markus 3574: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3575: {
1.367 djm 3576: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3577: Channel *c;
3578: struct channel_confirm *cc;
3579:
3580: /* Reset keepalive timeout */
1.389 djm 3581: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3582:
1.403 djm 3583: debug2_f("type %d id %d", type, id);
1.275 djm 3584:
1.367 djm 3585: if ((c = channel_lookup(ssh, id)) == NULL) {
1.403 djm 3586: logit_f("%d: unknown", id);
1.339 markus 3587: return 0;
1.367 djm 3588: }
1.363 markus 3589: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3590: return 0;
1.394 dtucker 3591: if (sshpkt_get_end(ssh) != 0)
1.389 djm 3592: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3593: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3594: return 0;
1.367 djm 3595: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3596: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 3597: freezero(cc, sizeof(*cc));
1.339 markus 3598: return 0;
1.275 djm 3599: }
1.121 markus 3600:
3601: /* -- tcp forwarding */
1.135 markus 3602:
3603: void
1.367 djm 3604: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3605: {
1.367 djm 3606: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3607: }
1.121 markus 3608:
1.312 djm 3609:
3610: /*
3611: * Determine whether or not a port forward listens to loopback, the
3612: * specified address or wildcard. On the client, a specified bind
3613: * address will always override gateway_ports. On the server, a
3614: * gateway_ports of 1 (``yes'') will override the client's specification
3615: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3616: * will bind to whatever address the client asked for.
3617: *
3618: * Special-case listen_addrs are:
3619: *
3620: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3621: * "" (empty string), "*" -> wildcard v4/v6
3622: * "localhost" -> loopback v4/v6
1.334 djm 3623: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3624: */
3625: static const char *
1.389 djm 3626: channel_fwd_bind_addr(struct ssh *ssh, const char *listen_addr, int *wildcardp,
1.336 millert 3627: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3628: {
3629: const char *addr = NULL;
3630: int wildcard = 0;
3631:
3632: if (listen_addr == NULL) {
3633: /* No address specified: default to gateway_ports setting */
1.336 millert 3634: if (fwd_opts->gateway_ports)
1.312 djm 3635: wildcard = 1;
1.336 millert 3636: } else if (fwd_opts->gateway_ports || is_client) {
1.404 djm 3637: if (((ssh->compat & SSH_OLD_FORWARD_ADDR) &&
1.312 djm 3638: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3639: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3640: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3641: wildcard = 1;
1.326 djm 3642: /*
3643: * Notify client if they requested a specific listen
3644: * address and it was overridden.
3645: */
3646: if (*listen_addr != '\0' &&
3647: strcmp(listen_addr, "0.0.0.0") != 0 &&
3648: strcmp(listen_addr, "*") != 0) {
1.389 djm 3649: ssh_packet_send_debug(ssh,
3650: "Forwarding listen address "
1.326 djm 3651: "\"%s\" overridden by server "
3652: "GatewayPorts", listen_addr);
3653: }
1.334 djm 3654: } else if (strcmp(listen_addr, "localhost") != 0 ||
3655: strcmp(listen_addr, "127.0.0.1") == 0 ||
3656: strcmp(listen_addr, "::1") == 0) {
1.395 djm 3657: /*
3658: * Accept explicit localhost address when
3659: * GatewayPorts=yes. The "localhost" hostname is
3660: * deliberately skipped here so it will listen on all
3661: * available local address families.
3662: */
1.334 djm 3663: addr = listen_addr;
1.326 djm 3664: }
1.334 djm 3665: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3666: strcmp(listen_addr, "::1") == 0) {
3667: /*
3668: * If a specific IPv4/IPv6 localhost address has been
3669: * requested then accept it even if gateway_ports is in
3670: * effect. This allows the client to prefer IPv4 or IPv6.
3671: */
3672: addr = listen_addr;
1.312 djm 3673: }
3674: if (wildcardp != NULL)
3675: *wildcardp = wildcard;
3676: return addr;
3677: }
3678:
1.160 markus 3679: static int
1.367 djm 3680: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3681: struct Forward *fwd, int *allocated_listen_port,
3682: struct ForwardOptions *fwd_opts)
1.25 markus 3683: {
1.113 markus 3684: Channel *c;
1.226 djm 3685: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3686: struct addrinfo hints, *ai, *aitop;
1.212 djm 3687: const char *host, *addr;
1.35 markus 3688: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3689: in_port_t *lport_p;
1.25 markus 3690:
1.212 djm 3691: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3692:
1.344 millert 3693: if (is_client && fwd->connect_path != NULL) {
3694: host = fwd->connect_path;
3695: } else {
3696: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3697: fwd->listen_host : fwd->connect_host;
3698: if (host == NULL) {
3699: error("No forward host name.");
3700: return 0;
3701: }
3702: if (strlen(host) >= NI_MAXHOST) {
3703: error("Forward host name too long.");
3704: return 0;
3705: }
1.87 markus 3706: }
1.25 markus 3707:
1.312 djm 3708: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3709: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3710: is_client, fwd_opts);
1.403 djm 3711: debug3_f("type %d wildcard %d addr %s", type, wildcard,
3712: (addr == NULL) ? "NULL" : addr);
1.212 djm 3713:
3714: /*
1.35 markus 3715: * getaddrinfo returns a loopback address if the hostname is
3716: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3717: */
1.35 markus 3718: memset(&hints, 0, sizeof(hints));
1.367 djm 3719: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3720: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3721: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3722: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3723: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3724: if (addr == NULL) {
3725: /* This really shouldn't happen */
1.389 djm 3726: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3727: ssh_gai_strerror(r));
1.212 djm 3728: } else {
1.403 djm 3729: error_f("getaddrinfo(%.64s): %s", addr,
1.271 dtucker 3730: ssh_gai_strerror(r));
1.212 djm 3731: }
1.218 markus 3732: return 0;
1.212 djm 3733: }
1.295 djm 3734: if (allocated_listen_port != NULL)
3735: *allocated_listen_port = 0;
1.35 markus 3736: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3737: switch (ai->ai_family) {
3738: case AF_INET:
3739: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3740: sin_port;
3741: break;
3742: case AF_INET6:
3743: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3744: sin6_port;
3745: break;
3746: default:
1.35 markus 3747: continue;
1.295 djm 3748: }
3749: /*
3750: * If allocating a port for -R forwards, then use the
3751: * same port for all address families.
3752: */
1.367 djm 3753: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3754: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3755: *allocated_listen_port > 0)
1.295 djm 3756: *lport_p = htons(*allocated_listen_port);
3757:
1.35 markus 3758: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3759: strport, sizeof(strport),
3760: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.403 djm 3761: error_f("getnameinfo failed");
1.35 markus 3762: continue;
3763: }
3764: /* Create a port to listen for the host. */
1.300 dtucker 3765: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 3766: if (sock == -1) {
1.35 markus 3767: /* this is no error since kernel may not support ipv6 */
1.377 djm 3768: verbose("socket [%s]:%s: %.100s", ntop, strport,
3769: strerror(errno));
1.35 markus 3770: continue;
3771: }
1.226 djm 3772:
1.376 djm 3773: set_reuseaddr(sock);
1.182 stevesk 3774:
1.295 djm 3775: debug("Local forwarding listening on %s port %s.",
3776: ntop, strport);
1.35 markus 3777:
3778: /* Bind the socket to the address. */
1.393 deraadt 3779: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3780: /*
3781: * address can be in if use ipv6 address is
3782: * already bound
3783: */
1.377 djm 3784: verbose("bind [%s]:%s: %.100s",
3785: ntop, strport, strerror(errno));
1.35 markus 3786: close(sock);
3787: continue;
3788: }
3789: /* Start listening for connections on the socket. */
1.393 deraadt 3790: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3791: error("listen [%s]:%s: %.100s", ntop, strport,
3792: strerror(errno));
1.35 markus 3793: close(sock);
3794: continue;
3795: }
1.295 djm 3796:
3797: /*
1.336 millert 3798: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3799: * record what we got.
3800: */
1.367 djm 3801: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3802: fwd->listen_port == 0 &&
1.295 djm 3803: allocated_listen_port != NULL &&
3804: *allocated_listen_port == 0) {
1.350 djm 3805: *allocated_listen_port = get_local_port(sock);
1.295 djm 3806: debug("Allocated listen port %d",
3807: *allocated_listen_port);
3808: }
3809:
1.35 markus 3810: /* Allocate a channel number for the socket. */
1.424 djm 3811: c = channel_new(ssh, "port-listener", type, sock, sock, -1,
1.51 markus 3812: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3813: 0, "port listener", 1);
1.293 djm 3814: c->path = xstrdup(host);
1.336 millert 3815: c->host_port = fwd->connect_port;
1.312 djm 3816: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3817: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.404 djm 3818: !(ssh->compat & SSH_BUG_DYNAMIC_RPORT))
1.315 markus 3819: c->listening_port = *allocated_listen_port;
3820: else
1.336 millert 3821: c->listening_port = fwd->listen_port;
1.35 markus 3822: success = 1;
3823: }
3824: if (success == 0)
1.403 djm 3825: error_f("cannot listen to port: %d", fwd->listen_port);
1.35 markus 3826: freeaddrinfo(aitop);
1.87 markus 3827: return success;
1.25 markus 3828: }
1.1 deraadt 3829:
1.336 millert 3830: static int
1.367 djm 3831: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3832: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3833: {
3834: struct sockaddr_un sunaddr;
3835: const char *path;
3836: Channel *c;
3837: int port, sock;
3838: mode_t omask;
3839:
3840: switch (type) {
3841: case SSH_CHANNEL_UNIX_LISTENER:
3842: if (fwd->connect_path != NULL) {
3843: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3844: error("Local connecting path too long: %s",
3845: fwd->connect_path);
3846: return 0;
3847: }
3848: path = fwd->connect_path;
3849: port = PORT_STREAMLOCAL;
3850: } else {
3851: if (fwd->connect_host == NULL) {
3852: error("No forward host name.");
3853: return 0;
3854: }
3855: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3856: error("Forward host name too long.");
3857: return 0;
3858: }
3859: path = fwd->connect_host;
3860: port = fwd->connect_port;
3861: }
3862: break;
3863: case SSH_CHANNEL_RUNIX_LISTENER:
3864: path = fwd->listen_path;
3865: port = PORT_STREAMLOCAL;
3866: break;
3867: default:
1.403 djm 3868: error_f("unexpected channel type %d", type);
1.336 millert 3869: return 0;
3870: }
3871:
3872: if (fwd->listen_path == NULL) {
3873: error("No forward path name.");
3874: return 0;
3875: }
3876: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3877: error("Local listening path too long: %s", fwd->listen_path);
3878: return 0;
3879: }
3880:
1.403 djm 3881: debug3_f("type %d path %s", type, fwd->listen_path);
1.336 millert 3882:
3883: /* Start a Unix domain listener. */
3884: omask = umask(fwd_opts->streamlocal_bind_mask);
3885: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3886: fwd_opts->streamlocal_bind_unlink);
3887: umask(omask);
3888: if (sock < 0)
3889: return 0;
3890:
3891: debug("Local forwarding listening on path %s.", fwd->listen_path);
3892:
3893: /* Allocate a channel number for the socket. */
1.424 djm 3894: c = channel_new(ssh, "unix-listener", type, sock, sock, -1,
1.336 millert 3895: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3896: 0, "unix listener", 1);
3897: c->path = xstrdup(path);
3898: c->host_port = port;
3899: c->listening_port = PORT_STREAMLOCAL;
3900: c->listening_addr = xstrdup(fwd->listen_path);
3901: return 1;
3902: }
3903:
3904: static int
1.367 djm 3905: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3906: const char *host, u_short port)
1.202 djm 3907: {
1.209 avsm 3908: u_int i;
3909: int found = 0;
1.202 djm 3910:
1.367 djm 3911: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3912: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3913: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3914: continue;
3915: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
1.403 djm 3916: debug2_f("close channel %d", i);
1.367 djm 3917: channel_free(ssh, c);
1.312 djm 3918: found = 1;
3919: }
3920: }
3921:
1.367 djm 3922: return found;
1.312 djm 3923: }
3924:
1.336 millert 3925: static int
1.367 djm 3926: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3927: {
3928: u_int i;
3929: int found = 0;
3930:
1.367 djm 3931: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3932: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3933: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3934: continue;
3935: if (c->path == NULL)
3936: continue;
3937: if (strcmp(c->path, path) == 0) {
1.403 djm 3938: debug2_f("close channel %d", i);
1.367 djm 3939: channel_free(ssh, c);
1.336 millert 3940: found = 1;
3941: }
3942: }
3943:
1.367 djm 3944: return found;
1.336 millert 3945: }
3946:
1.312 djm 3947: int
1.367 djm 3948: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3949: {
1.367 djm 3950: if (fwd->listen_path != NULL) {
3951: return channel_cancel_rport_listener_streamlocal(ssh,
3952: fwd->listen_path);
3953: } else {
3954: return channel_cancel_rport_listener_tcpip(ssh,
3955: fwd->listen_host, fwd->listen_port);
3956: }
1.336 millert 3957: }
3958:
3959: static int
1.367 djm 3960: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3961: const char *lhost, u_short lport, int cport,
3962: struct ForwardOptions *fwd_opts)
1.312 djm 3963: {
3964: u_int i;
3965: int found = 0;
1.389 djm 3966: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 3967:
1.367 djm 3968: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3969: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3970: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3971: continue;
1.313 markus 3972: if (c->listening_port != lport)
1.312 djm 3973: continue;
1.313 markus 3974: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3975: /* skip dynamic forwardings */
3976: if (c->host_port == 0)
3977: continue;
3978: } else {
3979: if (c->host_port != cport)
3980: continue;
3981: }
1.312 djm 3982: if ((c->listening_addr == NULL && addr != NULL) ||
3983: (c->listening_addr != NULL && addr == NULL))
3984: continue;
3985: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.403 djm 3986: debug2_f("close channel %d", i);
1.367 djm 3987: channel_free(ssh, c);
1.202 djm 3988: found = 1;
3989: }
3990: }
3991:
1.367 djm 3992: return found;
1.202 djm 3993: }
3994:
1.336 millert 3995: static int
1.367 djm 3996: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3997: {
3998: u_int i;
3999: int found = 0;
4000:
4001: if (path == NULL) {
1.403 djm 4002: error_f("no path specified.");
1.336 millert 4003: return 0;
4004: }
4005:
1.367 djm 4006: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
4007: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 4008: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
4009: continue;
4010: if (c->listening_addr == NULL)
4011: continue;
4012: if (strcmp(c->listening_addr, path) == 0) {
1.403 djm 4013: debug2_f("close channel %d", i);
1.367 djm 4014: channel_free(ssh, c);
1.336 millert 4015: found = 1;
4016: }
4017: }
4018:
1.367 djm 4019: return found;
1.336 millert 4020: }
4021:
4022: int
1.367 djm 4023: channel_cancel_lport_listener(struct ssh *ssh,
4024: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 4025: {
1.367 djm 4026: if (fwd->listen_path != NULL) {
4027: return channel_cancel_lport_listener_streamlocal(ssh,
4028: fwd->listen_path);
4029: } else {
4030: return channel_cancel_lport_listener_tcpip(ssh,
4031: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
4032: }
1.336 millert 4033: }
4034:
1.362 markus 4035: /* protocol local port fwd, used by ssh */
1.160 markus 4036: int
1.367 djm 4037: channel_setup_local_fwd_listener(struct ssh *ssh,
4038: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 4039: {
1.336 millert 4040: if (fwd->listen_path != NULL) {
1.367 djm 4041: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 4042: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
4043: } else {
1.367 djm 4044: return channel_setup_fwd_listener_tcpip(ssh,
4045: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 4046: }
1.160 markus 4047: }
4048:
1.381 djm 4049: /* Matches a remote forwarding permission against a requested forwarding */
4050: static int
4051: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
4052: {
4053: int ret;
4054: char *lhost;
4055:
4056: /* XXX add ACLs for streamlocal */
4057: if (fwd->listen_path != NULL)
4058: return 1;
4059:
4060: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
4061: return 0;
4062:
4063: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
4064: allowed_open->listen_port != fwd->listen_port)
4065: return 0;
4066:
4067: /* Match hostnames case-insensitively */
4068: lhost = xstrdup(fwd->listen_host);
4069: lowercase(lhost);
4070: ret = match_pattern(lhost, allowed_open->listen_host);
4071: free(lhost);
4072:
4073: return ret;
4074: }
4075:
4076: /* Checks whether a requested remote forwarding is permitted */
4077: static int
4078: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
4079: {
4080: struct ssh_channels *sc = ssh->chanctxt;
4081: struct permission_set *pset = &sc->remote_perms;
4082: u_int i, permit, permit_adm = 1;
4083: struct permission *perm;
4084:
4085: /* XXX apply GatewayPorts override before checking? */
4086:
4087: permit = pset->all_permitted;
4088: if (!permit) {
4089: for (i = 0; i < pset->num_permitted_user; i++) {
4090: perm = &pset->permitted_user[i];
4091: if (remote_open_match(perm, fwd)) {
4092: permit = 1;
4093: break;
4094: }
4095: }
4096: }
4097:
4098: if (pset->num_permitted_admin > 0) {
4099: permit_adm = 0;
4100: for (i = 0; i < pset->num_permitted_admin; i++) {
4101: perm = &pset->permitted_admin[i];
4102: if (remote_open_match(perm, fwd)) {
4103: permit_adm = 1;
4104: break;
4105: }
4106: }
4107: }
4108:
4109: return permit && permit_adm;
4110: }
4111:
1.160 markus 4112: /* protocol v2 remote port fwd, used by sshd */
4113: int
1.367 djm 4114: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 4115: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 4116: {
1.381 djm 4117: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 4118: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 4119: if (fwd->listen_path != NULL)
4120: /* XXX always allowed, see remote_open_match() */
4121: logit("Received request from %.100s port %d to "
4122: "remote forward to path \"%.100s\", "
4123: "but the request was denied.",
4124: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
4125: fwd->listen_path);
4126: else if(fwd->listen_host != NULL)
4127: logit("Received request from %.100s port %d to "
4128: "remote forward to host %.100s port %d, "
4129: "but the request was denied.",
4130: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
4131: fwd->listen_host, fwd->listen_port );
4132: else
4133: logit("Received request from %.100s port %d to remote "
4134: "forward, but the request was denied.",
4135: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 4136: return 0;
4137: }
1.336 millert 4138: if (fwd->listen_path != NULL) {
1.367 djm 4139: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 4140: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
4141: } else {
1.367 djm 4142: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 4143: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
4144: fwd_opts);
4145: }
1.160 markus 4146: }
4147:
1.27 markus 4148: /*
1.312 djm 4149: * Translate the requested rfwd listen host to something usable for
4150: * this server.
4151: */
4152: static const char *
4153: channel_rfwd_bind_host(const char *listen_host)
4154: {
4155: if (listen_host == NULL) {
1.378 djm 4156: return "localhost";
1.312 djm 4157: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 4158: return "";
1.312 djm 4159: } else
4160: return listen_host;
4161: }
4162:
4163: /*
1.27 markus 4164: * Initiate forwarding of connections to port "port" on remote host through
4165: * the secure channel to host:port from local side.
1.315 markus 4166: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 4167: * channel_update_permission().
1.27 markus 4168: */
1.253 markus 4169: int
1.367 djm 4170: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 4171: {
1.367 djm 4172: int r, success = 0, idx = -1;
1.421 mbuhl 4173: const char *host_to_connect, *listen_host, *listen_path;
1.367 djm 4174: int port_to_connect, listen_port;
1.73 markus 4175:
1.25 markus 4176: /* Send the forward request to the remote side. */
1.358 djm 4177: if (fwd->listen_path != NULL) {
1.367 djm 4178: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4179: (r = sshpkt_put_cstring(ssh,
4180: "streamlocal-forward@openssh.com")) != 0 ||
4181: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4182: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
4183: (r = sshpkt_send(ssh)) != 0 ||
4184: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4185: fatal_fr(r, "request streamlocal");
1.336 millert 4186: } else {
1.367 djm 4187: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4188: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
4189: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4190: (r = sshpkt_put_cstring(ssh,
4191: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
4192: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
4193: (r = sshpkt_send(ssh)) != 0 ||
4194: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4195: fatal_fr(r, "request tcpip-forward");
1.73 markus 4196: }
1.358 djm 4197: /* Assume that server accepts the request */
4198: success = 1;
1.73 markus 4199: if (success) {
1.305 djm 4200: /* Record that connection to this host/port is permitted. */
1.367 djm 4201: host_to_connect = listen_host = listen_path = NULL;
4202: port_to_connect = listen_port = 0;
1.336 millert 4203: if (fwd->connect_path != NULL) {
1.421 mbuhl 4204: host_to_connect = fwd->connect_path;
1.367 djm 4205: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 4206: } else {
1.421 mbuhl 4207: host_to_connect = fwd->connect_host;
1.367 djm 4208: port_to_connect = fwd->connect_port;
1.336 millert 4209: }
4210: if (fwd->listen_path != NULL) {
1.421 mbuhl 4211: listen_path = fwd->listen_path;
1.367 djm 4212: listen_port = PORT_STREAMLOCAL;
1.336 millert 4213: } else {
1.421 mbuhl 4214: listen_host = fwd->listen_host;
1.367 djm 4215: listen_port = fwd->listen_port;
4216: }
1.381 djm 4217: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 4218: host_to_connect, port_to_connect,
4219: listen_host, listen_path, listen_port, NULL);
1.44 markus 4220: }
1.367 djm 4221: return idx;
1.1 deraadt 4222: }
4223:
1.333 markus 4224: static int
1.381 djm 4225: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 4226: int requestedport)
1.333 markus 4227: {
4228: if (allowed_open->host_to_connect == NULL)
4229: return 0;
4230: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
4231: allowed_open->port_to_connect != requestedport)
4232: return 0;
1.351 dtucker 4233: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
4234: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 4235: return 0;
4236: return 1;
4237: }
4238:
4239: /*
1.336 millert 4240: * Note that in the listen host/port case
1.333 markus 4241: * we don't support FWD_PERMIT_ANY_PORT and
4242: * need to translate between the configured-host (listen_host)
4243: * and what we've sent to the remote server (channel_rfwd_bind_host)
4244: */
4245: static int
1.381 djm 4246: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 4247: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 4248: {
4249: const char *allowed_host;
4250:
4251: if (allowed_open->host_to_connect == NULL)
4252: return 0;
4253: if (allowed_open->listen_port != requestedport)
4254: return 0;
1.335 djm 4255: if (!translate && allowed_open->listen_host == NULL &&
4256: requestedhost == NULL)
4257: return 1;
1.333 markus 4258: allowed_host = translate ?
4259: channel_rfwd_bind_host(allowed_open->listen_host) :
4260: allowed_open->listen_host;
1.382 djm 4261: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 4262: strcmp(allowed_host, requestedhost) != 0)
4263: return 0;
4264: return 1;
4265: }
4266:
1.336 millert 4267: static int
1.381 djm 4268: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 4269: const char *requestedpath)
4270: {
4271: if (allowed_open->host_to_connect == NULL)
4272: return 0;
4273: if (allowed_open->listen_port != PORT_STREAMLOCAL)
4274: return 0;
4275: if (allowed_open->listen_path == NULL ||
4276: strcmp(allowed_open->listen_path, requestedpath) != 0)
4277: return 0;
4278: return 1;
4279: }
4280:
1.27 markus 4281: /*
1.208 deraadt 4282: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 4283: * local side.
4284: */
1.336 millert 4285: static int
1.367 djm 4286: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
4287: const char *host, u_short port)
1.202 djm 4288: {
1.367 djm 4289: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4290: struct permission_set *pset = &sc->local_perms;
1.367 djm 4291: int r;
4292: u_int i;
1.397 markus 4293: struct permission *perm = NULL;
1.202 djm 4294:
1.381 djm 4295: for (i = 0; i < pset->num_permitted_user; i++) {
4296: perm = &pset->permitted_user[i];
4297: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 4298: break;
1.381 djm 4299: perm = NULL;
1.202 djm 4300: }
1.381 djm 4301: if (perm == NULL) {
1.403 djm 4302: debug_f("requested forward not found");
1.312 djm 4303: return -1;
1.202 djm 4304: }
1.367 djm 4305: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4306: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
4307: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4308: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
4309: (r = sshpkt_put_u32(ssh, port)) != 0 ||
4310: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4311: fatal_fr(r, "send cancel");
1.367 djm 4312:
1.381 djm 4313: fwd_perm_clear(perm); /* unregister */
1.336 millert 4314:
4315: return 0;
4316: }
4317:
4318: /*
4319: * Request cancellation of remote forwarding of Unix domain socket
4320: * path from local side.
4321: */
4322: static int
1.367 djm 4323: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 4324: {
1.367 djm 4325: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4326: struct permission_set *pset = &sc->local_perms;
1.367 djm 4327: int r;
4328: u_int i;
1.397 markus 4329: struct permission *perm = NULL;
1.336 millert 4330:
1.381 djm 4331: for (i = 0; i < pset->num_permitted_user; i++) {
4332: perm = &pset->permitted_user[i];
4333: if (open_listen_match_streamlocal(perm, path))
1.336 millert 4334: break;
1.381 djm 4335: perm = NULL;
1.336 millert 4336: }
1.381 djm 4337: if (perm == NULL) {
1.403 djm 4338: debug_f("requested forward not found");
1.336 millert 4339: return -1;
4340: }
1.367 djm 4341: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4342: (r = sshpkt_put_cstring(ssh,
4343: "cancel-streamlocal-forward@openssh.com")) != 0 ||
4344: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4345: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
4346: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4347: fatal_fr(r, "send cancel");
1.367 djm 4348:
1.381 djm 4349: fwd_perm_clear(perm); /* unregister */
1.312 djm 4350:
4351: return 0;
1.202 djm 4352: }
4353:
4354: /*
1.336 millert 4355: * Request cancellation of remote forwarding of a connection from local side.
4356: */
4357: int
1.367 djm 4358: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 4359: {
4360: if (fwd->listen_path != NULL) {
1.367 djm 4361: return channel_request_rforward_cancel_streamlocal(ssh,
4362: fwd->listen_path);
1.336 millert 4363: } else {
1.367 djm 4364: return channel_request_rforward_cancel_tcpip(ssh,
4365: fwd->listen_host,
4366: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 4367: }
1.1 deraadt 4368: }
4369:
1.99 markus 4370: /*
1.381 djm 4371: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 4372: * usually called by the server, because the user could connect to any port
4373: * anyway, and the server has no way to know but to trust the client anyway.
4374: */
4375: void
1.381 djm 4376: channel_permit_all(struct ssh *ssh, int where)
4377: {
4378: struct permission_set *pset = permission_set_get(ssh, where);
4379:
4380: if (pset->num_permitted_user == 0)
4381: pset->all_permitted = 1;
4382: }
4383:
4384: /*
4385: * Permit the specified host/port for forwarding.
4386: */
4387: void
4388: channel_add_permission(struct ssh *ssh, int who, int where,
4389: char *host, int port)
4390: {
4391: int local = where == FORWARD_LOCAL;
4392: struct permission_set *pset = permission_set_get(ssh, where);
4393:
4394: debug("allow %s forwarding to host %s port %d",
4395: fwd_ident(who, where), host, port);
4396: /*
4397: * Remote forwards set listen_host/port, local forwards set
4398: * host/port_to_connect.
4399: */
4400: permission_set_add(ssh, who, where,
4401: local ? host : 0, local ? port : 0,
4402: local ? NULL : host, NULL, local ? 0 : port, NULL);
4403: pset->all_permitted = 0;
4404: }
4405:
4406: /*
4407: * Administratively disable forwarding.
4408: */
4409: void
4410: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4411: {
1.381 djm 4412: channel_clear_permission(ssh, FORWARD_ADM, where);
4413: permission_set_add(ssh, FORWARD_ADM, where,
4414: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4415: }
4416:
1.381 djm 4417: /*
4418: * Clear a list of permitted opens.
4419: */
1.101 markus 4420: void
1.381 djm 4421: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4422: {
1.381 djm 4423: struct permission **permp;
4424: u_int *npermp;
1.367 djm 4425:
1.381 djm 4426: permission_set_get_array(ssh, who, where, &permp, &npermp);
4427: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4428: *npermp = 0;
1.315 markus 4429: }
4430:
4431: /*
4432: * Update the listen port for a dynamic remote forward, after
4433: * the actual 'newport' has been allocated. If 'newport' < 0 is
4434: * passed then they entry will be invalidated.
4435: */
4436: void
1.381 djm 4437: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4438: {
1.381 djm 4439: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4440:
1.381 djm 4441: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
1.403 djm 4442: debug_f("index out of range: %d num_permitted_user %d",
4443: idx, pset->num_permitted_user);
1.315 markus 4444: return;
4445: }
4446: debug("%s allowed port %d for forwarding to host %s port %d",
4447: newport > 0 ? "Updating" : "Removing",
4448: newport,
1.381 djm 4449: pset->permitted_user[idx].host_to_connect,
4450: pset->permitted_user[idx].port_to_connect);
1.367 djm 4451: if (newport <= 0)
1.381 djm 4452: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4453: else {
1.381 djm 4454: pset->permitted_user[idx].listen_port =
1.404 djm 4455: (ssh->compat & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
1.315 markus 4456: }
1.99 markus 4457: }
4458:
1.314 dtucker 4459: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4460: int
4461: permitopen_port(const char *p)
4462: {
4463: int port;
4464:
4465: if (strcmp(p, "*") == 0)
4466: return FWD_PERMIT_ANY_PORT;
4467: if ((port = a2port(p)) > 0)
4468: return port;
4469: return -1;
4470: }
4471:
1.276 djm 4472: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4473: static int
1.276 djm 4474: connect_next(struct channel_connect *cctx)
1.41 markus 4475: {
1.276 djm 4476: int sock, saved_errno;
1.336 millert 4477: struct sockaddr_un *sunaddr;
1.367 djm 4478: char ntop[NI_MAXHOST];
4479: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4480:
1.276 djm 4481: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4482: switch (cctx->ai->ai_family) {
4483: case AF_UNIX:
4484: /* unix:pathname instead of host:port */
4485: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4486: strlcpy(ntop, "unix", sizeof(ntop));
4487: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4488: break;
4489: case AF_INET:
4490: case AF_INET6:
4491: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4492: ntop, sizeof(ntop), strport, sizeof(strport),
4493: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.420 djm 4494: error_f("getnameinfo failed");
1.336 millert 4495: continue;
4496: }
4497: break;
4498: default:
1.41 markus 4499: continue;
4500: }
1.420 djm 4501: debug_f("start for host %.100s ([%.100s]:%s)",
4502: cctx->host, ntop, strport);
1.300 dtucker 4503: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4504: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4505: if (cctx->ai->ai_next == NULL)
1.186 djm 4506: error("socket: %.100s", strerror(errno));
4507: else
4508: verbose("socket: %.100s", strerror(errno));
1.41 markus 4509: continue;
4510: }
1.205 djm 4511: if (set_nonblock(sock) == -1)
1.403 djm 4512: fatal_f("set_nonblock(%d)", sock);
1.276 djm 4513: if (connect(sock, cctx->ai->ai_addr,
4514: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
1.420 djm 4515: debug_f("host %.100s ([%.100s]:%s): %.100s",
4516: cctx->host, ntop, strport, strerror(errno));
1.276 djm 4517: saved_errno = errno;
1.41 markus 4518: close(sock);
1.276 djm 4519: errno = saved_errno;
1.89 stevesk 4520: continue; /* fail -- try next */
1.41 markus 4521: }
1.336 millert 4522: if (cctx->ai->ai_family != AF_UNIX)
4523: set_nodelay(sock);
1.420 djm 4524: debug_f("connect host %.100s ([%.100s]:%s) in progress, fd=%d",
4525: cctx->host, ntop, strport, sock);
1.276 djm 4526: cctx->ai = cctx->ai->ai_next;
4527: return sock;
4528: }
4529: return -1;
4530: }
1.41 markus 4531:
1.276 djm 4532: static void
4533: channel_connect_ctx_free(struct channel_connect *cctx)
4534: {
1.321 djm 4535: free(cctx->host);
1.336 millert 4536: if (cctx->aitop) {
4537: if (cctx->aitop->ai_family == AF_UNIX)
4538: free(cctx->aitop);
4539: else
4540: freeaddrinfo(cctx->aitop);
4541: }
1.329 tedu 4542: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4543: }
4544:
1.357 dtucker 4545: /*
1.372 markus 4546: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4547: * passing back the failure reason if appropriate.
4548: */
1.372 markus 4549: static int
4550: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4551: char *ctype, char *rname, struct channel_connect *cctx,
4552: int *reason, const char **errmsg)
1.276 djm 4553: {
4554: struct addrinfo hints;
4555: int gaierr;
4556: int sock = -1;
4557: char strport[NI_MAXSERV];
1.336 millert 4558:
4559: if (port == PORT_STREAMLOCAL) {
4560: struct sockaddr_un *sunaddr;
4561: struct addrinfo *ai;
4562:
4563: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4564: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4565: return -1;
1.336 millert 4566: }
4567:
4568: /*
4569: * Fake up a struct addrinfo for AF_UNIX connections.
4570: * channel_connect_ctx_free() must check ai_family
4571: * and use free() not freeaddirinfo() for AF_UNIX.
4572: */
4573: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4574: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4575: ai->ai_addr = (struct sockaddr *)(ai + 1);
4576: ai->ai_addrlen = sizeof(*sunaddr);
4577: ai->ai_family = AF_UNIX;
1.372 markus 4578: ai->ai_socktype = socktype;
1.336 millert 4579: ai->ai_protocol = PF_UNSPEC;
4580: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4581: sunaddr->sun_family = AF_UNIX;
4582: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4583: cctx->aitop = ai;
1.336 millert 4584: } else {
4585: memset(&hints, 0, sizeof(hints));
1.367 djm 4586: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4587: hints.ai_socktype = socktype;
1.336 millert 4588: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4589: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4590: != 0) {
4591: if (errmsg != NULL)
4592: *errmsg = ssh_gai_strerror(gaierr);
4593: if (reason != NULL)
4594: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4595: error("connect_to %.100s: unknown host (%s)", name,
4596: ssh_gai_strerror(gaierr));
1.372 markus 4597: return -1;
1.336 millert 4598: }
1.41 markus 4599: }
1.276 djm 4600:
1.372 markus 4601: cctx->host = xstrdup(name);
4602: cctx->port = port;
4603: cctx->ai = cctx->aitop;
1.276 djm 4604:
1.372 markus 4605: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4606: error("connect to %.100s port %d failed: %s",
1.336 millert 4607: name, port, strerror(errno));
1.372 markus 4608: return -1;
4609: }
4610:
4611: return sock;
4612: }
4613:
4614: /* Return CONNECTING channel to remote host:port or local socket path */
4615: static Channel *
4616: connect_to(struct ssh *ssh, const char *host, int port,
4617: char *ctype, char *rname)
4618: {
4619: struct channel_connect cctx;
4620: Channel *c;
4621: int sock;
4622:
4623: memset(&cctx, 0, sizeof(cctx));
4624: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4625: &cctx, NULL, NULL);
4626: if (sock == -1) {
1.276 djm 4627: channel_connect_ctx_free(&cctx);
4628: return NULL;
1.41 markus 4629: }
1.367 djm 4630: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4631: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4632: c->host_port = port;
4633: c->path = xstrdup(host);
1.276 djm 4634: c->connect_ctx = cctx;
1.372 markus 4635:
1.276 djm 4636: return c;
1.41 markus 4637: }
1.99 markus 4638:
1.354 markus 4639: /*
4640: * returns either the newly connected channel or the downstream channel
4641: * that needs to deal with this connection.
4642: */
1.276 djm 4643: Channel *
1.367 djm 4644: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4645: u_short listen_port, char *ctype, char *rname)
1.73 markus 4646: {
1.367 djm 4647: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4648: struct permission_set *pset = &sc->local_perms;
1.367 djm 4649: u_int i;
1.381 djm 4650: struct permission *perm;
1.99 markus 4651:
1.381 djm 4652: for (i = 0; i < pset->num_permitted_user; i++) {
4653: perm = &pset->permitted_user[i];
4654: if (open_listen_match_tcpip(perm,
4655: listen_host, listen_port, 1)) {
4656: if (perm->downstream)
4657: return perm->downstream;
4658: if (perm->port_to_connect == 0)
1.372 markus 4659: return rdynamic_connect_prepare(ssh,
4660: ctype, rname);
1.367 djm 4661: return connect_to(ssh,
1.381 djm 4662: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4663: ctype, rname);
1.276 djm 4664: }
4665: }
1.74 markus 4666: error("WARNING: Server requests forwarding for unknown listen_port %d",
4667: listen_port);
1.276 djm 4668: return NULL;
1.73 markus 4669: }
4670:
1.336 millert 4671: Channel *
1.367 djm 4672: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4673: char *ctype, char *rname)
1.336 millert 4674: {
1.367 djm 4675: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4676: struct permission_set *pset = &sc->local_perms;
1.367 djm 4677: u_int i;
1.381 djm 4678: struct permission *perm;
1.336 millert 4679:
1.381 djm 4680: for (i = 0; i < pset->num_permitted_user; i++) {
4681: perm = &pset->permitted_user[i];
4682: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4683: return connect_to(ssh,
1.381 djm 4684: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4685: ctype, rname);
1.336 millert 4686: }
4687: }
4688: error("WARNING: Server requests forwarding for unknown path %.100s",
4689: path);
4690: return NULL;
4691: }
4692:
1.99 markus 4693: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4694: Channel *
1.367 djm 4695: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4696: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4697: {
1.367 djm 4698: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4699: struct permission_set *pset = &sc->local_perms;
1.372 markus 4700: struct channel_connect cctx;
4701: Channel *c;
1.367 djm 4702: u_int i, permit, permit_adm = 1;
1.372 markus 4703: int sock;
1.381 djm 4704: struct permission *perm;
1.99 markus 4705:
1.381 djm 4706: permit = pset->all_permitted;
1.99 markus 4707: if (!permit) {
1.381 djm 4708: for (i = 0; i < pset->num_permitted_user; i++) {
4709: perm = &pset->permitted_user[i];
4710: if (open_match(perm, host, port)) {
1.99 markus 4711: permit = 1;
1.333 markus 4712: break;
4713: }
1.367 djm 4714: }
1.257 dtucker 4715: }
1.99 markus 4716:
1.381 djm 4717: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4718: permit_adm = 0;
1.381 djm 4719: for (i = 0; i < pset->num_permitted_admin; i++) {
4720: perm = &pset->permitted_admin[i];
4721: if (open_match(perm, host, port)) {
1.257 dtucker 4722: permit_adm = 1;
1.333 markus 4723: break;
4724: }
1.367 djm 4725: }
1.99 markus 4726: }
1.257 dtucker 4727:
4728: if (!permit || !permit_adm) {
1.391 florian 4729: logit("Received request from %.100s port %d to connect to "
4730: "host %.100s port %d, but the request was denied.",
4731: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4732: if (reason != NULL)
4733: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4734: return NULL;
1.99 markus 4735: }
1.372 markus 4736:
4737: memset(&cctx, 0, sizeof(cctx));
4738: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4739: &cctx, reason, errmsg);
4740: if (sock == -1) {
4741: channel_connect_ctx_free(&cctx);
4742: return NULL;
4743: }
4744:
4745: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4746: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4747: c->host_port = port;
4748: c->path = xstrdup(host);
4749: c->connect_ctx = cctx;
4750:
4751: return c;
1.336 millert 4752: }
4753:
4754: /* Check if connecting to that path is permitted and connect. */
4755: Channel *
1.367 djm 4756: channel_connect_to_path(struct ssh *ssh, const char *path,
4757: char *ctype, char *rname)
1.336 millert 4758: {
1.367 djm 4759: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4760: struct permission_set *pset = &sc->local_perms;
1.367 djm 4761: u_int i, permit, permit_adm = 1;
1.381 djm 4762: struct permission *perm;
1.336 millert 4763:
1.381 djm 4764: permit = pset->all_permitted;
1.336 millert 4765: if (!permit) {
1.381 djm 4766: for (i = 0; i < pset->num_permitted_user; i++) {
4767: perm = &pset->permitted_user[i];
4768: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4769: permit = 1;
4770: break;
4771: }
1.367 djm 4772: }
1.336 millert 4773: }
4774:
1.381 djm 4775: if (pset->num_permitted_admin > 0) {
1.336 millert 4776: permit_adm = 0;
1.381 djm 4777: for (i = 0; i < pset->num_permitted_admin; i++) {
4778: perm = &pset->permitted_admin[i];
4779: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4780: permit_adm = 1;
4781: break;
4782: }
1.367 djm 4783: }
1.336 millert 4784: }
4785:
4786: if (!permit || !permit_adm) {
4787: logit("Received request to connect to path %.100s, "
4788: "but the request was denied.", path);
4789: return NULL;
4790: }
1.367 djm 4791: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4792: }
4793:
4794: void
1.367 djm 4795: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4796: {
1.367 djm 4797: struct ssh_channels *sc = ssh->chanctxt;
4798: struct winsize ws;
4799: int r;
1.209 avsm 4800: u_int i;
1.204 djm 4801:
1.367 djm 4802: for (i = 0; i < sc->channels_alloc; i++) {
4803: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4804: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4805: continue;
1.393 deraadt 4806: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4807: continue;
1.367 djm 4808: channel_request_start(ssh, i, "window-change", 0);
4809: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4810: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4811: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4812: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4813: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4814: fatal_fr(r, "channel %u; send window-change", i);
1.204 djm 4815: }
1.372 markus 4816: }
4817:
4818: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4819: static Channel *
4820: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4821: {
4822: Channel *c;
4823: int r;
4824:
4825: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4826: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4827: c->host_port = 0;
4828: c->path = NULL;
4829:
4830: /*
4831: * We need to open the channel before we have a FD,
4832: * so that we can get SOCKS header from peer.
4833: */
4834: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4835: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4836: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4837: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 4838: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0)
4839: fatal_fr(r, "channel %i; confirm", c->self);
1.372 markus 4840: return c;
4841: }
4842:
4843: /* Return CONNECTING socket to remote host:port or local socket path */
4844: static int
4845: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4846: {
1.405 markus 4847: struct ssh_channels *sc = ssh->chanctxt;
4848: struct permission_set *pset = &sc->local_perms;
4849: struct permission *perm;
1.372 markus 4850: struct channel_connect cctx;
1.405 markus 4851: u_int i, permit_adm = 1;
1.372 markus 4852: int sock;
1.405 markus 4853:
4854: if (pset->num_permitted_admin > 0) {
4855: permit_adm = 0;
4856: for (i = 0; i < pset->num_permitted_admin; i++) {
4857: perm = &pset->permitted_admin[i];
4858: if (open_match(perm, c->path, c->host_port)) {
4859: permit_adm = 1;
4860: break;
4861: }
4862: }
4863: }
4864: if (!permit_adm) {
4865: debug_f("requested forward not permitted");
4866: return -1;
4867: }
1.372 markus 4868:
4869: memset(&cctx, 0, sizeof(cctx));
4870: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4871: NULL, &cctx, NULL, NULL);
4872: if (sock == -1)
4873: channel_connect_ctx_free(&cctx);
4874: else {
4875: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4876: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4877: c->connect_ctx = cctx;
4878: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4879: }
4880: return sock;
1.99 markus 4881: }
4882:
1.121 markus 4883: /* -- X11 forwarding */
1.1 deraadt 4884:
1.27 markus 4885: /*
4886: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4887: * Returns 0 and a suitable display number for the DISPLAY variable
4888: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4889: */
1.141 stevesk 4890: int
1.367 djm 4891: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4892: int x11_use_localhost, int single_connection,
4893: u_int *display_numberp, int **chanids)
1.1 deraadt 4894: {
1.149 markus 4895: Channel *nc = NULL;
1.31 markus 4896: int display_number, sock;
4897: u_short port;
1.35 markus 4898: struct addrinfo hints, *ai, *aitop;
4899: char strport[NI_MAXSERV];
4900: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4901:
1.224 markus 4902: if (chanids == NULL)
4903: return -1;
4904:
1.33 markus 4905: for (display_number = x11_display_offset;
1.148 deraadt 4906: display_number < MAX_DISPLAYS;
4907: display_number++) {
1.25 markus 4908: port = 6000 + display_number;
1.35 markus 4909: memset(&hints, 0, sizeof(hints));
1.367 djm 4910: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4911: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4912: hints.ai_socktype = SOCK_STREAM;
4913: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4914: if ((gaierr = getaddrinfo(NULL, strport,
4915: &hints, &aitop)) != 0) {
1.271 dtucker 4916: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4917: return -1;
1.25 markus 4918: }
1.35 markus 4919: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4920: if (ai->ai_family != AF_INET &&
4921: ai->ai_family != AF_INET6)
1.35 markus 4922: continue;
1.300 dtucker 4923: sock = socket(ai->ai_family, ai->ai_socktype,
4924: ai->ai_protocol);
1.393 deraadt 4925: if (sock == -1) {
1.35 markus 4926: error("socket: %.100s", strerror(errno));
1.203 markus 4927: freeaddrinfo(aitop);
1.141 stevesk 4928: return -1;
1.35 markus 4929: }
1.376 djm 4930: set_reuseaddr(sock);
1.393 deraadt 4931: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.403 djm 4932: debug2_f("bind port %d: %.100s", port,
4933: strerror(errno));
1.35 markus 4934: close(sock);
1.367 djm 4935: for (n = 0; n < num_socks; n++)
1.35 markus 4936: close(socks[n]);
4937: num_socks = 0;
4938: break;
4939: }
4940: socks[num_socks++] = sock;
4941: if (num_socks == NUM_SOCKS)
4942: break;
1.25 markus 4943: }
1.83 stevesk 4944: freeaddrinfo(aitop);
1.35 markus 4945: if (num_socks > 0)
4946: break;
1.25 markus 4947: }
4948: if (display_number >= MAX_DISPLAYS) {
4949: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4950: return -1;
1.25 markus 4951: }
4952: /* Start listening for connections on the socket. */
1.35 markus 4953: for (n = 0; n < num_socks; n++) {
4954: sock = socks[n];
1.393 deraadt 4955: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 4956: error("listen: %.100s", strerror(errno));
4957: close(sock);
1.141 stevesk 4958: return -1;
1.35 markus 4959: }
1.25 markus 4960: }
1.35 markus 4961:
4962: /* Allocate a channel for each socket. */
1.242 djm 4963: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4964: for (n = 0; n < num_socks; n++) {
4965: sock = socks[n];
1.424 djm 4966: nc = channel_new(ssh, "x11-listener",
1.51 markus 4967: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4968: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4969: 0, "X11 inet listener", 1);
1.167 markus 4970: nc->single_connection = single_connection;
1.224 markus 4971: (*chanids)[n] = nc->self;
1.35 markus 4972: }
1.224 markus 4973: (*chanids)[n] = -1;
1.1 deraadt 4974:
1.141 stevesk 4975: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4976: *display_numberp = display_number;
1.367 djm 4977: return 0;
1.1 deraadt 4978: }
4979:
1.127 itojun 4980: static int
1.77 markus 4981: connect_local_xsocket(u_int dnr)
1.1 deraadt 4982: {
1.25 markus 4983: int sock;
4984: struct sockaddr_un addr;
4985:
1.147 stevesk 4986: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 deraadt 4987: if (sock == -1)
1.147 stevesk 4988: error("socket: %.100s", strerror(errno));
4989: memset(&addr, 0, sizeof(addr));
4990: addr.sun_family = AF_UNIX;
4991: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4992: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4993: return sock;
4994: close(sock);
1.25 markus 4995: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4996: return -1;
1.1 deraadt 4997: }
4998:
1.51 markus 4999: int
1.367 djm 5000: x11_connect_display(struct ssh *ssh)
1.1 deraadt 5001: {
1.248 deraadt 5002: u_int display_number;
1.25 markus 5003: const char *display;
1.51 markus 5004: char buf[1024], *cp;
1.35 markus 5005: struct addrinfo hints, *ai, *aitop;
5006: char strport[NI_MAXSERV];
1.248 deraadt 5007: int gaierr, sock = 0;
1.25 markus 5008:
5009: /* Try to open a socket for the local X server. */
5010: display = getenv("DISPLAY");
5011: if (!display) {
5012: error("DISPLAY not set.");
1.51 markus 5013: return -1;
1.25 markus 5014: }
1.27 markus 5015: /*
5016: * Now we decode the value of the DISPLAY variable and make a
5017: * connection to the real X server.
5018: */
5019:
5020: /*
5021: * Check if it is a unix domain socket. Unix domain displays are in
5022: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
5023: */
1.25 markus 5024: if (strncmp(display, "unix:", 5) == 0 ||
5025: display[0] == ':') {
5026: /* Connect to the unix domain socket. */
1.367 djm 5027: if (sscanf(strrchr(display, ':') + 1, "%u",
5028: &display_number) != 1) {
5029: error("Could not parse display number from DISPLAY: "
5030: "%.100s", display);
1.51 markus 5031: return -1;
1.25 markus 5032: }
5033: /* Create a socket. */
5034: sock = connect_local_xsocket(display_number);
5035: if (sock < 0)
1.51 markus 5036: return -1;
1.25 markus 5037:
5038: /* OK, we now have a connection to the display. */
1.51 markus 5039: return sock;
1.25 markus 5040: }
1.27 markus 5041: /*
5042: * Connect to an inet socket. The DISPLAY value is supposedly
5043: * hostname:d[.s], where hostname may also be numeric IP address.
5044: */
1.145 stevesk 5045: strlcpy(buf, display, sizeof(buf));
1.25 markus 5046: cp = strchr(buf, ':');
5047: if (!cp) {
5048: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 5049: return -1;
1.25 markus 5050: }
5051: *cp = 0;
1.367 djm 5052: /*
5053: * buf now contains the host name. But first we parse the
5054: * display number.
5055: */
1.248 deraadt 5056: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 5057: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 5058: display);
1.51 markus 5059: return -1;
1.25 markus 5060: }
1.35 markus 5061:
5062: /* Look up the host address */
5063: memset(&hints, 0, sizeof(hints));
1.367 djm 5064: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 5065: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 5066: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 5067: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 5068: error("%.100s: unknown host. (%s)", buf,
5069: ssh_gai_strerror(gaierr));
1.51 markus 5070: return -1;
1.25 markus 5071: }
1.35 markus 5072: for (ai = aitop; ai; ai = ai->ai_next) {
5073: /* Create a socket. */
1.300 dtucker 5074: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 5075: if (sock == -1) {
1.194 markus 5076: debug2("socket: %.100s", strerror(errno));
1.41 markus 5077: continue;
5078: }
5079: /* Connect it to the display. */
1.393 deraadt 5080: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 5081: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 5082: 6000 + display_number, strerror(errno));
5083: close(sock);
5084: continue;
5085: }
5086: /* Success */
5087: break;
1.35 markus 5088: }
5089: freeaddrinfo(aitop);
5090: if (!ai) {
1.367 djm 5091: error("connect %.100s port %u: %.100s", buf,
5092: 6000 + display_number, strerror(errno));
1.51 markus 5093: return -1;
1.25 markus 5094: }
1.162 stevesk 5095: set_nodelay(sock);
1.51 markus 5096: return sock;
5097: }
5098:
5099: /*
1.27 markus 5100: * Requests forwarding of X11 connections, generates fake authentication
5101: * data, and enables authentication spoofing.
1.121 markus 5102: * This should be called in the client only.
1.27 markus 5103: */
1.49 markus 5104: void
1.367 djm 5105: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
5106: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 5107: {
1.367 djm 5108: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 5109: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 5110: u_int i, value;
1.367 djm 5111: const char *cp;
1.25 markus 5112: char *new_data;
1.367 djm 5113: int r, screen_number;
1.25 markus 5114:
1.367 djm 5115: if (sc->x11_saved_display == NULL)
5116: sc->x11_saved_display = xstrdup(disp);
5117: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 5118: error("x11_request_forwarding_with_spoofing: different "
5119: "$DISPLAY already forwarded");
5120: return;
5121: }
5122:
1.266 djm 5123: cp = strchr(disp, ':');
1.25 markus 5124: if (cp)
5125: cp = strchr(cp, '.');
5126: if (cp)
1.245 deraadt 5127: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 5128: else
5129: screen_number = 0;
5130:
1.367 djm 5131: if (sc->x11_saved_proto == NULL) {
1.219 djm 5132: /* Save protocol name. */
1.367 djm 5133: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 5134:
5135: /* Extract real authentication data. */
1.367 djm 5136: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 5137: for (i = 0; i < data_len; i++) {
1.403 djm 5138: if (sscanf(data + 2 * i, "%2x", &value) != 1) {
1.219 djm 5139: fatal("x11_request_forwarding: bad "
5140: "authentication data: %.100s", data);
1.403 djm 5141: }
1.367 djm 5142: sc->x11_saved_data[i] = value;
1.219 djm 5143: }
1.367 djm 5144: sc->x11_saved_data_len = data_len;
1.353 natano 5145:
5146: /* Generate fake data of the same length. */
1.367 djm 5147: sc->x11_fake_data = xmalloc(data_len);
5148: arc4random_buf(sc->x11_fake_data, data_len);
5149: sc->x11_fake_data_len = data_len;
1.25 markus 5150: }
5151:
5152: /* Convert the fake data into hex. */
1.367 djm 5153: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 5154:
5155: /* Send the request packet. */
1.367 djm 5156: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
5157: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
5158: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
5159: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
5160: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
5161: (r = sshpkt_send(ssh)) != 0 ||
5162: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 5163: fatal_fr(r, "send x11-req");
1.321 djm 5164: free(new_data);
1.1 deraadt 5165: }