Annotation of src/usr.bin/ssh/channels.c, Revision 1.430
1.430 ! dtucker 1: /* $OpenBSD: channels.c,v 1.429 2023/03/07 21:47:42 djm Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.336 millert 43: #include <sys/stat.h>
1.234 stevesk 44: #include <sys/ioctl.h>
1.235 stevesk 45: #include <sys/un.h>
1.251 stevesk 46: #include <sys/socket.h>
1.261 stevesk 47: #include <sys/time.h>
1.275 djm 48: #include <sys/queue.h>
1.251 stevesk 49:
50: #include <netinet/in.h>
51: #include <arpa/inet.h>
1.233 stevesk 52:
1.254 stevesk 53: #include <errno.h>
1.298 dtucker 54: #include <fcntl.h>
1.367 djm 55: #include <limits.h>
1.255 stevesk 56: #include <netdb.h>
1.411 djm 57: #include <poll.h>
1.367 djm 58: #include <stdarg.h>
1.341 millert 59: #include <stdint.h>
1.263 stevesk 60: #include <stdio.h>
1.262 stevesk 61: #include <stdlib.h>
1.260 stevesk 62: #include <string.h>
1.233 stevesk 63: #include <termios.h>
1.256 stevesk 64: #include <unistd.h>
1.1 deraadt 65:
1.265 deraadt 66: #include "xmalloc.h"
1.1 deraadt 67: #include "ssh.h"
1.82 markus 68: #include "ssh2.h"
1.354 markus 69: #include "ssherr.h"
1.367 djm 70: #include "sshbuf.h"
1.1 deraadt 71: #include "packet.h"
1.82 markus 72: #include "log.h"
73: #include "misc.h"
1.14 markus 74: #include "channels.h"
75: #include "compat.h"
1.82 markus 76: #include "canohost.h"
1.383 markus 77: #include "sshkey.h"
1.64 markus 78: #include "authfd.h"
1.147 stevesk 79: #include "pathnames.h"
1.381 djm 80: #include "match.h"
1.388 djm 81:
1.411 djm 82: /* XXX remove once we're satisfied there's no lurking bugs */
83: /* #define DEBUG_CHANNEL_POLL 1 */
84:
1.367 djm 85: /* -- agent forwarding */
86: #define NUM_SOCKS 10
1.12 markus 87:
1.367 djm 88: /* -- tcp forwarding */
89: /* special-case port number meaning allow any port */
90: #define FWD_PERMIT_ANY_PORT 0
1.1 deraadt 91:
1.367 djm 92: /* special-case wildcard meaning allow any host */
93: #define FWD_PERMIT_ANY_HOST "*"
1.1 deraadt 94:
1.367 djm 95: /* -- X11 forwarding */
96: /* Maximum number of fake X11 displays to try. */
97: #define MAX_DISPLAYS 1000
1.1 deraadt 98:
1.411 djm 99: /* Per-channel callback for pre/post IO actions */
1.410 djm 100: typedef void chan_fn(struct ssh *, Channel *c);
1.381 djm 101:
1.27 markus 102: /*
103: * Data structure for storing which hosts are permitted for forward requests.
104: * The local sides of any remote forwards are stored in this array to prevent
105: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
106: * network (which might be behind a firewall).
107: */
1.336 millert 108: /* XXX: streamlocal wants a path instead of host:port */
109: /* Overload host_to_connect; we could just make this match Forward */
110: /* XXX - can we use listen_host instead of listen_path? */
1.381 djm 111: struct permission {
1.41 markus 112: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 113: int port_to_connect; /* Connect to 'port'. */
1.333 markus 114: char *listen_host; /* Remote side should listen address. */
1.336 millert 115: char *listen_path; /* Remote side should listen path. */
116: int listen_port; /* Remote side should listen port. */
1.354 markus 117: Channel *downstream; /* Downstream mux*/
1.381 djm 118: };
119:
120: /*
121: * Stores the forwarding permission state for a single direction (local or
122: * remote).
123: */
124: struct permission_set {
125: /*
126: * List of all local permitted host/port pairs to allow for the
127: * user.
128: */
129: u_int num_permitted_user;
130: struct permission *permitted_user;
1.1 deraadt 131:
1.381 djm 132: /*
133: * List of all permitted host/port pairs to allow for the admin.
134: */
135: u_int num_permitted_admin;
136: struct permission *permitted_admin;
137:
138: /*
139: * If this is true, all opens/listens are permitted. This is the
140: * case on the server on which we have to trust the client anyway,
141: * and the user could do anything after logging in.
142: */
143: int all_permitted;
144: };
1.121 markus 145:
1.426 djm 146: /* Used to record timeouts per channel type */
147: struct ssh_channel_timeout {
148: char *type_pattern;
149: u_int timeout_secs;
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,
307: u_int timeout_secs)
308: {
309: struct ssh_channels *sc = ssh->chanctxt;
310:
311: debug2_f("channel type \"%s\" timeout %u seconds",
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:
335: static u_int
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,
1.407 djm 1625: const char *host_to_connect, u_short port_to_connect,
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);
1642: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1643:
1644: return c;
1.193 markus 1645: }
1646:
1.104 markus 1647: /* dynamic port forwarding */
1.127 itojun 1648: static void
1.410 djm 1649: channel_pre_dynamic(struct ssh *ssh, Channel *c)
1.104 markus 1650: {
1.367 djm 1651: const u_char *p;
1.217 djm 1652: u_int have;
1653: int ret;
1.103 markus 1654:
1.410 djm 1655: c->io_want = 0;
1.367 djm 1656: have = sshbuf_len(c->input);
1.104 markus 1657: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1658: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1659: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1660: if (have < 3) {
1.104 markus 1661: /* need more */
1.410 djm 1662: c->io_want |= SSH_CHAN_IO_RFD;
1.104 markus 1663: return;
1664: }
1665: /* try to guess the protocol */
1.367 djm 1666: p = sshbuf_ptr(c->input);
1667: /* XXX sshbuf_peek_u8? */
1.104 markus 1668: switch (p[0]) {
1669: case 0x04:
1.372 markus 1670: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1671: break;
1672: case 0x05:
1.372 markus 1673: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1674: break;
1675: default:
1676: ret = -1;
1677: break;
1678: }
1679: if (ret < 0) {
1.367 djm 1680: chan_mark_dead(ssh, c);
1.104 markus 1681: } else if (ret == 0) {
1682: debug2("channel %d: pre_dynamic: need more", c->self);
1683: /* need more */
1.410 djm 1684: c->io_want |= SSH_CHAN_IO_RFD;
1.372 markus 1685: if (sshbuf_len(c->output))
1.410 djm 1686: c->io_want |= SSH_CHAN_IO_WFD;
1.104 markus 1687: } else {
1688: /* switch to the next state */
1689: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1690: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1691: }
1.103 markus 1692: }
1693:
1.372 markus 1694: /* simulate read-error */
1695: static void
1696: rdynamic_close(struct ssh *ssh, Channel *c)
1697: {
1698: c->type = SSH_CHANNEL_OPEN;
1.423 djm 1699: channel_force_close(ssh, c, 0);
1.372 markus 1700: }
1701:
1702: /* reverse dynamic port forwarding */
1703: static void
1.411 djm 1704: channel_before_prepare_io_rdynamic(struct ssh *ssh, Channel *c)
1.372 markus 1705: {
1706: const u_char *p;
1707: u_int have, len;
1708: int r, ret;
1709:
1710: have = sshbuf_len(c->output);
1711: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1712: /* sshbuf_dump(c->output, stderr); */
1713: /* EOF received */
1714: if (c->flags & CHAN_EOF_RCVD) {
1.403 djm 1715: if ((r = sshbuf_consume(c->output, have)) != 0)
1716: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1717: rdynamic_close(ssh, c);
1718: return;
1719: }
1720: /* check if the fixed size part of the packet is in buffer. */
1721: if (have < 3)
1722: return;
1723: /* try to guess the protocol */
1724: p = sshbuf_ptr(c->output);
1725: switch (p[0]) {
1726: case 0x04:
1727: /* switch input/output for reverse forwarding */
1728: ret = channel_decode_socks4(c, c->output, c->input);
1729: break;
1730: case 0x05:
1731: ret = channel_decode_socks5(c, c->output, c->input);
1732: break;
1733: default:
1734: ret = -1;
1735: break;
1736: }
1737: if (ret < 0) {
1738: rdynamic_close(ssh, c);
1739: } else if (ret == 0) {
1740: debug2("channel %d: pre_rdynamic: need more", c->self);
1741: /* send socks request to peer */
1742: len = sshbuf_len(c->input);
1743: if (len > 0 && len < c->remote_window) {
1744: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1745: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1746: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1747: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 1748: fatal_fr(r, "channel %i: rdynamic", c->self);
1.372 markus 1749: }
1.403 djm 1750: if ((r = sshbuf_consume(c->input, len)) != 0)
1751: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1752: c->remote_window -= len;
1753: }
1754: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1755: /* the connect failed */
1756: rdynamic_close(ssh, c);
1757: }
1758: }
1759:
1.41 markus 1760: /* This is our fake X11 server socket. */
1.127 itojun 1761: static void
1.410 djm 1762: channel_post_x11_listener(struct ssh *ssh, Channel *c)
1.41 markus 1763: {
1.113 markus 1764: Channel *nc;
1.285 djm 1765: struct sockaddr_storage addr;
1.367 djm 1766: int r, newsock, oerrno, remote_port;
1.41 markus 1767: socklen_t addrlen;
1.85 markus 1768: char buf[16384], *remote_ipaddr;
1.25 markus 1769:
1.410 djm 1770: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1771: return;
1772:
1773: debug("X11 connection requested.");
1774: addrlen = sizeof(addr);
1775: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1776: if (c->single_connection) {
1777: oerrno = errno;
1778: debug2("single_connection: closing X11 listener.");
1.407 djm 1779: channel_close_fd(ssh, c, &c->sock);
1.367 djm 1780: chan_mark_dead(ssh, c);
1781: errno = oerrno;
1782: }
1.393 deraadt 1783: if (newsock == -1) {
1.367 djm 1784: if (errno != EINTR && errno != EWOULDBLOCK &&
1785: errno != ECONNABORTED)
1786: error("accept: %.100s", strerror(errno));
1787: if (errno == EMFILE || errno == ENFILE)
1788: c->notbefore = monotime() + 1;
1789: return;
1790: }
1791: set_nodelay(newsock);
1792: remote_ipaddr = get_peer_ipaddr(newsock);
1793: remote_port = get_peer_port(newsock);
1794: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1795: remote_ipaddr, remote_port);
1796:
1.424 djm 1797: nc = channel_new(ssh, "x11-connection",
1.367 djm 1798: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1799: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1800: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1801: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1802: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.403 djm 1803: fatal_fr(r, "channel %i: reply", c->self);
1.41 markus 1804: }
1.367 djm 1805: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1806: fatal_fr(r, "channel %i: send", c->self);
1.367 djm 1807: free(remote_ipaddr);
1.41 markus 1808: }
1.25 markus 1809:
1.127 itojun 1810: static void
1.367 djm 1811: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1812: {
1.328 djm 1813: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1814: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1815: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1816: int remote_port = get_peer_port(c->sock);
1.367 djm 1817: int r;
1.303 djm 1818:
1819: if (remote_port == -1) {
1820: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1821: free(remote_ipaddr);
1.303 djm 1822: remote_ipaddr = xstrdup("127.0.0.1");
1823: remote_port = 65535;
1824: }
1.103 markus 1825:
1.367 djm 1826: free(c->remote_name);
1827: xasprintf(&c->remote_name,
1.103 markus 1828: "%s: listening port %d for %.100s port %d, "
1.328 djm 1829: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1830: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1831: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1832:
1.367 djm 1833: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1834: if (strcmp(rtype, "direct-tcpip") == 0) {
1835: /* target host, port */
1.367 djm 1836: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1837: (r = sshpkt_put_u32(ssh, c->host_port)) != 0)
1838: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1839: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1840: /* target path */
1.403 djm 1841: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1842: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1843: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1844: /* listen path */
1.403 djm 1845: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1846: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1847: } else {
1.358 djm 1848: /* listen address, port */
1.367 djm 1849: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1850: (r = sshpkt_put_u32(ssh, local_port)) != 0)
1851: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1852: }
1853: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1854: /* reserved for future owner/mode info */
1.403 djm 1855: if ((r = sshpkt_put_cstring(ssh, "")) != 0)
1856: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1857: } else {
1858: /* originator host and port */
1.367 djm 1859: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1.403 djm 1860: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0)
1861: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1862: }
1.367 djm 1863: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1864: fatal_fr(r, "channel %i: send", c->self);
1.321 djm 1865: free(remote_ipaddr);
1.328 djm 1866: free(local_ipaddr);
1.103 markus 1867: }
1868:
1.347 djm 1869: void
1.428 dtucker 1870: channel_set_x11_refuse_time(struct ssh *ssh, time_t refuse_time)
1.347 djm 1871: {
1.367 djm 1872: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1873: }
1874:
1.41 markus 1875: /*
1876: * This socket is listening for connections to a forwarded TCP/IP port.
1877: */
1.127 itojun 1878: static void
1.410 djm 1879: channel_post_port_listener(struct ssh *ssh, Channel *c)
1.41 markus 1880: {
1.103 markus 1881: Channel *nc;
1.285 djm 1882: struct sockaddr_storage addr;
1.113 markus 1883: int newsock, nextstate;
1.41 markus 1884: socklen_t addrlen;
1.103 markus 1885: char *rtype;
1.73 markus 1886:
1.410 djm 1887: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1888: return;
1889:
1890: debug("Connection to port %d forwarding to %.100s port %d requested.",
1891: c->listening_port, c->path, c->host_port);
1.103 markus 1892:
1.367 djm 1893: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1894: nextstate = SSH_CHANNEL_OPENING;
1895: rtype = "forwarded-tcpip";
1896: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1897: nextstate = SSH_CHANNEL_OPENING;
1898: rtype = "forwarded-streamlocal@openssh.com";
1899: } else if (c->host_port == PORT_STREAMLOCAL) {
1900: nextstate = SSH_CHANNEL_OPENING;
1901: rtype = "direct-streamlocal@openssh.com";
1902: } else if (c->host_port == 0) {
1903: nextstate = SSH_CHANNEL_DYNAMIC;
1904: rtype = "dynamic-tcpip";
1905: } else {
1906: nextstate = SSH_CHANNEL_OPENING;
1907: rtype = "direct-tcpip";
1908: }
1.103 markus 1909:
1.367 djm 1910: addrlen = sizeof(addr);
1911: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1912: if (newsock == -1) {
1.367 djm 1913: if (errno != EINTR && errno != EWOULDBLOCK &&
1914: errno != ECONNABORTED)
1915: error("accept: %.100s", strerror(errno));
1916: if (errno == EMFILE || errno == ENFILE)
1917: c->notbefore = monotime() + 1;
1918: return;
1.41 markus 1919: }
1.367 djm 1920: if (c->host_port != PORT_STREAMLOCAL)
1921: set_nodelay(newsock);
1922: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1923: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1924: nc->listening_port = c->listening_port;
1925: nc->host_port = c->host_port;
1926: if (c->path != NULL)
1927: nc->path = xstrdup(c->path);
1928:
1929: if (nextstate != SSH_CHANNEL_DYNAMIC)
1930: port_open_helper(ssh, nc, rtype);
1.41 markus 1931: }
1.25 markus 1932:
1.41 markus 1933: /*
1934: * This is the authentication agent socket listening for connections from
1935: * clients.
1936: */
1.127 itojun 1937: static void
1.410 djm 1938: channel_post_auth_listener(struct ssh *ssh, Channel *c)
1.41 markus 1939: {
1.113 markus 1940: Channel *nc;
1.367 djm 1941: int r, newsock;
1.285 djm 1942: struct sockaddr_storage addr;
1.41 markus 1943: socklen_t addrlen;
1.25 markus 1944:
1.410 djm 1945: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1946: return;
1947:
1948: addrlen = sizeof(addr);
1949: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1950: if (newsock == -1) {
1.367 djm 1951: error("accept from auth socket: %.100s", strerror(errno));
1952: if (errno == EMFILE || errno == ENFILE)
1953: c->notbefore = monotime() + 1;
1954: return;
1.41 markus 1955: }
1.424 djm 1956: nc = channel_new(ssh, "agent-connection",
1.367 djm 1957: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1958: c->local_window_max, c->local_maxpacket,
1959: 0, "accepted auth socket", 1);
1960: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1961: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1962: fatal_fr(r, "channel %i", c->self);
1.41 markus 1963: }
1.25 markus 1964:
1.127 itojun 1965: static void
1.410 djm 1966: channel_post_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1967: {
1.372 markus 1968: int err = 0, sock, isopen, r;
1.129 stevesk 1969: socklen_t sz = sizeof(err);
1.114 markus 1970:
1.410 djm 1971: if ((c->io_ready & SSH_CHAN_IO_SOCK_W) == 0)
1.367 djm 1972: return;
1.368 djm 1973: if (!c->have_remote_id)
1.403 djm 1974: fatal_f("channel %d: no remote id", c->self);
1.372 markus 1975: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1976: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.429 djm 1977:
1.393 deraadt 1978: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 1979: err = errno;
1980: error("getsockopt SO_ERROR failed");
1981: }
1.429 djm 1982:
1.367 djm 1983: if (err == 0) {
1.429 djm 1984: /* Non-blocking connection completed */
1.367 djm 1985: debug("channel %d: connected to %s port %d",
1986: c->self, c->connect_ctx.host, c->connect_ctx.port);
1987: channel_connect_ctx_free(&c->connect_ctx);
1988: c->type = SSH_CHANNEL_OPEN;
1.426 djm 1989: c->lastused = monotime();
1.372 markus 1990: if (isopen) {
1991: /* no message necessary */
1992: } else {
1993: if ((r = sshpkt_start(ssh,
1994: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1995: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1996: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1997: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 1998: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0 ||
1999: (r = sshpkt_send(ssh)) != 0)
2000: fatal_fr(r, "channel %i open confirm", c->self);
1.367 djm 2001: }
1.429 djm 2002: return;
2003: }
2004: if (err == EINTR || err == EAGAIN || err == EINPROGRESS)
2005: return;
2006:
2007: /* Non-blocking connection failed */
2008: debug("channel %d: connection failed: %s", c->self, strerror(err));
2009:
2010: /* Try next address, if any */
2011: if ((sock = connect_next(&c->connect_ctx)) == -1) {
2012: /* Exhausted all addresses for this destination */
1.367 djm 2013: error("connect_to %.100s port %d: failed.",
2014: c->connect_ctx.host, c->connect_ctx.port);
2015: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 2016: if (isopen) {
2017: rdynamic_close(ssh, c);
2018: } else {
2019: if ((r = sshpkt_start(ssh,
2020: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
2021: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 2022: (r = sshpkt_put_u32(ssh,
2023: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
2024: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1.403 djm 2025: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2026: (r = sshpkt_send(ssh)) != 0)
2027: fatal_fr(r, "channel %i: failure", c->self);
1.372 markus 2028: chan_mark_dead(ssh, c);
1.75 markus 2029: }
2030: }
1.429 djm 2031:
2032: /* New non-blocking connection in progress */
2033: close(c->sock);
2034: c->sock = c->rfd = c->wfd = sock;
1.75 markus 2035: }
2036:
1.127 itojun 2037: static int
1.410 djm 2038: channel_handle_rfd(struct ssh *ssh, Channel *c)
1.41 markus 2039: {
1.214 markus 2040: char buf[CHAN_RBUF];
1.367 djm 2041: ssize_t len;
2042: int r;
1.426 djm 2043: size_t nr = 0, have, avail, maxlen = CHANNEL_MAX_READ;
1.25 markus 2044:
1.410 djm 2045: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.412 djm 2046: return 1; /* Shouldn't happen */
2047: if ((avail = sshbuf_avail(c->input)) == 0)
2048: return 1; /* Shouldn't happen */
2049:
2050: /*
2051: * For "simple" channels (i.e. not datagram or filtered), we can
2052: * read directly to the channel buffer.
2053: */
2054: if (c->input_filter == NULL && !c->datagram) {
2055: /* Only OPEN channels have valid rwin */
2056: if (c->type == SSH_CHANNEL_OPEN) {
2057: if ((have = sshbuf_len(c->input)) >= c->remote_window)
2058: return 1; /* shouldn't happen */
2059: if (maxlen > c->remote_window - have)
2060: maxlen = c->remote_window - have;
2061: }
2062: if (maxlen > avail)
2063: maxlen = avail;
1.426 djm 2064: if ((r = sshbuf_read(c->rfd, c->input, maxlen, &nr)) != 0) {
1.413 djm 2065: if (errno == EINTR || errno == EAGAIN)
2066: return 1;
1.412 djm 2067: debug2("channel %d: read failed rfd %d maxlen %zu: %s",
2068: c->self, c->rfd, maxlen, ssh_err(r));
2069: goto rfail;
2070: }
1.426 djm 2071: if (nr != 0)
2072: c->lastused = monotime();
1.367 djm 2073: return 1;
1.412 djm 2074: }
1.367 djm 2075:
2076: len = read(c->rfd, buf, sizeof(buf));
1.393 deraadt 2077: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2078: return 1;
2079: if (len <= 0) {
1.412 djm 2080: debug2("channel %d: read<=0 rfd %d len %zd: %s",
2081: c->self, c->rfd, len,
2082: len == 0 ? "closed" : strerror(errno));
2083: rfail:
1.367 djm 2084: if (c->type != SSH_CHANNEL_OPEN) {
2085: debug2("channel %d: not open", c->self);
2086: chan_mark_dead(ssh, c);
1.41 markus 2087: return -1;
1.65 markus 2088: } else {
1.367 djm 2089: chan_read_failed(ssh, c);
1.65 markus 2090: }
1.367 djm 2091: return -1;
2092: }
1.426 djm 2093: c->lastused = monotime();
1.367 djm 2094: if (c->input_filter != NULL) {
2095: if (c->input_filter(ssh, c, buf, len) == -1) {
2096: debug2("channel %d: filter stops", c->self);
2097: chan_read_failed(ssh, c);
2098: }
2099: } else if (c->datagram) {
2100: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1.403 djm 2101: fatal_fr(r, "channel %i: put datagram", c->self);
1.412 djm 2102: }
1.41 markus 2103: return 1;
2104: }
1.241 deraadt 2105:
1.127 itojun 2106: static int
1.410 djm 2107: channel_handle_wfd(struct ssh *ssh, Channel *c)
1.41 markus 2108: {
1.95 markus 2109: struct termios tio;
1.367 djm 2110: u_char *data = NULL, *buf; /* XXX const; need filter API change */
2111: size_t dlen, olen = 0;
2112: int r, len;
2113:
1.410 djm 2114: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
2115: return 1;
2116: if (sshbuf_len(c->output) == 0)
1.367 djm 2117: return 1;
1.25 markus 2118:
1.41 markus 2119: /* Send buffered output data to the socket. */
1.367 djm 2120: olen = sshbuf_len(c->output);
2121: if (c->output_filter != NULL) {
2122: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
2123: debug2("channel %d: filter stops", c->self);
2124: if (c->type != SSH_CHANNEL_OPEN)
2125: chan_mark_dead(ssh, c);
2126: else
2127: chan_write_failed(ssh, c);
2128: return -1;
1.231 reyk 2129: }
1.367 djm 2130: } else if (c->datagram) {
2131: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1.403 djm 2132: fatal_fr(r, "channel %i: get datagram", c->self);
1.369 djm 2133: buf = data;
1.367 djm 2134: } else {
2135: buf = data = sshbuf_mutable_ptr(c->output);
2136: dlen = sshbuf_len(c->output);
2137: }
1.231 reyk 2138:
1.367 djm 2139: if (c->datagram) {
2140: /* ignore truncated writes, datagrams might get lost */
1.374 djm 2141: len = write(c->wfd, buf, dlen);
1.367 djm 2142: free(data);
1.393 deraadt 2143: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 2144: return 1;
1.367 djm 2145: if (len <= 0)
2146: goto write_fail;
2147: goto out;
2148: }
2149:
2150: len = write(c->wfd, buf, dlen);
1.393 deraadt 2151: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2152: return 1;
2153: if (len <= 0) {
2154: write_fail:
2155: if (c->type != SSH_CHANNEL_OPEN) {
2156: debug2("channel %d: not open", c->self);
2157: chan_mark_dead(ssh, c);
1.41 markus 2158: return -1;
1.367 djm 2159: } else {
2160: chan_write_failed(ssh, c);
1.91 markus 2161: }
1.367 djm 2162: return -1;
2163: }
1.426 djm 2164: c->lastused = monotime();
1.367 djm 2165: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2166: if (tcgetattr(c->wfd, &tio) == 0 &&
2167: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2168: /*
2169: * Simulate echo to reduce the impact of
2170: * traffic analysis. We need to match the
2171: * size of a SSH2_MSG_CHANNEL_DATA message
2172: * (4 byte channel id + buf)
2173: */
2174: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2175: (r = sshpkt_send(ssh)) != 0)
1.403 djm 2176: fatal_fr(r, "channel %i: ignore", c->self);
1.25 markus 2177: }
1.367 djm 2178: }
1.403 djm 2179: if ((r = sshbuf_consume(c->output, len)) != 0)
2180: fatal_fr(r, "channel %i: consume", c->self);
1.309 djm 2181: out:
1.367 djm 2182: c->local_consumed += olen - sshbuf_len(c->output);
2183:
2184: return 1;
2185: }
2186:
2187: static int
1.410 djm 2188: channel_handle_efd_write(struct ssh *ssh, Channel *c)
1.367 djm 2189: {
2190: int r;
2191: ssize_t len;
2192:
1.410 djm 2193: if ((c->io_ready & SSH_CHAN_IO_EFD_W) == 0)
2194: return 1;
2195: if (sshbuf_len(c->extended) == 0)
1.367 djm 2196: return 1;
2197:
2198: len = write(c->efd, sshbuf_ptr(c->extended),
2199: sshbuf_len(c->extended));
2200: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 deraadt 2201: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2202: return 1;
2203: if (len <= 0) {
2204: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1.407 djm 2205: channel_close_fd(ssh, c, &c->efd);
1.367 djm 2206: } else {
1.403 djm 2207: if ((r = sshbuf_consume(c->extended, len)) != 0)
2208: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2209: c->local_consumed += len;
1.426 djm 2210: c->lastused = monotime();
1.367 djm 2211: }
1.44 markus 2212: return 1;
2213: }
1.241 deraadt 2214:
1.127 itojun 2215: static int
1.410 djm 2216: channel_handle_efd_read(struct ssh *ssh, Channel *c)
1.44 markus 2217: {
1.214 markus 2218: char buf[CHAN_RBUF];
1.367 djm 2219: int r;
2220: ssize_t len;
2221:
1.410 djm 2222: if ((c->io_ready & SSH_CHAN_IO_EFD_R) == 0)
1.367 djm 2223: return 1;
1.44 markus 2224:
1.367 djm 2225: len = read(c->efd, buf, sizeof(buf));
2226: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 deraadt 2227: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2228: return 1;
2229: if (len <= 0) {
1.403 djm 2230: debug2("channel %d: closing read-efd %d", c->self, c->efd);
1.407 djm 2231: channel_close_fd(ssh, c, &c->efd);
1.426 djm 2232: return 1;
2233: }
2234: c->lastused = monotime();
2235: if (c->extended_usage == CHAN_EXTENDED_IGNORE)
1.403 djm 2236: debug3("channel %d: discard efd", c->self);
2237: else if ((r = sshbuf_put(c->extended, buf, len)) != 0)
2238: fatal_fr(r, "channel %i: append", c->self);
1.44 markus 2239: return 1;
2240: }
1.241 deraadt 2241:
1.127 itojun 2242: static int
1.410 djm 2243: channel_handle_efd(struct ssh *ssh, Channel *c)
1.44 markus 2244: {
1.367 djm 2245: if (c->efd == -1)
2246: return 1;
2247:
2248: /** XXX handle drain efd, too */
2249:
2250: if (c->extended_usage == CHAN_EXTENDED_WRITE)
1.410 djm 2251: return channel_handle_efd_write(ssh, c);
1.367 djm 2252: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2253: c->extended_usage == CHAN_EXTENDED_IGNORE)
1.410 djm 2254: return channel_handle_efd_read(ssh, c);
1.367 djm 2255:
2256: return 1;
2257: }
2258:
2259: static int
2260: channel_check_window(struct ssh *ssh, Channel *c)
2261: {
2262: int r;
2263:
1.104 markus 2264: if (c->type == SSH_CHANNEL_OPEN &&
2265: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2266: ((c->local_window_max - c->local_window >
1.269 markus 2267: c->local_maxpacket*3) ||
2268: c->local_window < c->local_window_max/2) &&
1.44 markus 2269: c->local_consumed > 0) {
1.368 djm 2270: if (!c->have_remote_id)
1.403 djm 2271: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2272: if ((r = sshpkt_start(ssh,
2273: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2274: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2275: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2276: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2277: fatal_fr(r, "channel %i", c->self);
1.367 djm 2278: }
1.403 djm 2279: debug2("channel %d: window %d sent adjust %d", c->self,
2280: c->local_window, c->local_consumed);
1.44 markus 2281: c->local_window += c->local_consumed;
2282: c->local_consumed = 0;
1.1 deraadt 2283: }
1.41 markus 2284: return 1;
1.1 deraadt 2285: }
2286:
1.127 itojun 2287: static void
1.410 djm 2288: channel_post_open(struct ssh *ssh, Channel *c)
1.41 markus 2289: {
1.410 djm 2290: channel_handle_rfd(ssh, c);
2291: channel_handle_wfd(ssh, c);
2292: channel_handle_efd(ssh, c);
1.367 djm 2293: channel_check_window(ssh, c);
1.44 markus 2294: }
2295:
1.302 djm 2296: static u_int
1.367 djm 2297: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2298: {
2299: char buf[CHAN_RBUF];
1.367 djm 2300: ssize_t len;
1.302 djm 2301: u_int rlen;
1.367 djm 2302: int r;
1.302 djm 2303:
1.367 djm 2304: if (sshbuf_len(c->input) < need) {
2305: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2306: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 deraadt 2307: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2308: return sshbuf_len(c->input);
1.302 djm 2309: if (len <= 0) {
1.367 djm 2310: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2311: c->self, c->rfd, len);
1.367 djm 2312: chan_read_failed(ssh, c);
1.349 naddy 2313: return 0;
1.403 djm 2314: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
2315: fatal_fr(r, "channel %i: append", c->self);
1.302 djm 2316: }
1.367 djm 2317: return sshbuf_len(c->input);
1.302 djm 2318: }
2319:
2320: static void
1.410 djm 2321: channel_post_mux_client_read(struct ssh *ssh, Channel *c)
1.302 djm 2322: {
2323: u_int need;
2324:
1.410 djm 2325: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.367 djm 2326: return;
2327: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2328: return;
2329: if (c->mux_pause)
2330: return;
2331:
2332: /*
2333: * Don't not read past the precise end of packets to
2334: * avoid disrupting fd passing.
2335: */
2336: if (read_mux(ssh, c, 4) < 4) /* read header */
2337: return;
2338: /* XXX sshbuf_peek_u32 */
2339: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2340: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2341: if (need > CHANNEL_MUX_MAX_PACKET) {
2342: debug2("channel %d: packet too big %u > %u",
2343: c->self, CHANNEL_MUX_MAX_PACKET, need);
2344: chan_rcvd_oclose(ssh, c);
2345: return;
2346: }
2347: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2348: return;
2349: if (c->mux_rcb(ssh, c) != 0) {
2350: debug("channel %d: mux_rcb failed", c->self);
2351: chan_mark_dead(ssh, c);
2352: return;
1.302 djm 2353: }
1.367 djm 2354: }
2355:
2356: static void
1.410 djm 2357: channel_post_mux_client_write(struct ssh *ssh, Channel *c)
1.367 djm 2358: {
2359: ssize_t len;
2360: int r;
1.302 djm 2361:
1.410 djm 2362: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
2363: return;
2364: if (sshbuf_len(c->output) == 0)
1.367 djm 2365: return;
2366:
2367: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 deraadt 2368: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2369: return;
2370: if (len <= 0) {
2371: chan_mark_dead(ssh, c);
2372: return;
1.302 djm 2373: }
1.367 djm 2374: if ((r = sshbuf_consume(c->output, len)) != 0)
1.403 djm 2375: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2376: }
2377:
2378: static void
1.410 djm 2379: channel_post_mux_client(struct ssh *ssh, Channel *c)
1.367 djm 2380: {
1.410 djm 2381: channel_post_mux_client_read(ssh, c);
2382: channel_post_mux_client_write(ssh, c);
1.302 djm 2383: }
2384:
2385: static void
1.410 djm 2386: channel_post_mux_listener(struct ssh *ssh, Channel *c)
1.302 djm 2387: {
2388: Channel *nc;
2389: struct sockaddr_storage addr;
2390: socklen_t addrlen;
2391: int newsock;
2392: uid_t euid;
2393: gid_t egid;
2394:
1.410 djm 2395: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.302 djm 2396: return;
2397:
2398: debug("multiplexing control connection");
2399:
2400: /*
2401: * Accept connection on control socket
2402: */
2403: memset(&addr, 0, sizeof(addr));
2404: addrlen = sizeof(addr);
2405: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2406: &addrlen)) == -1) {
1.403 djm 2407: error_f("accept: %s", strerror(errno));
1.317 djm 2408: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2409: c->notbefore = monotime() + 1;
1.302 djm 2410: return;
2411: }
2412:
1.393 deraadt 2413: if (getpeereid(newsock, &euid, &egid) == -1) {
1.403 djm 2414: error_f("getpeereid failed: %s", strerror(errno));
1.302 djm 2415: close(newsock);
2416: return;
2417: }
2418: if ((euid != 0) && (getuid() != euid)) {
2419: error("multiplex uid mismatch: peer euid %u != uid %u",
2420: (u_int)euid, (u_int)getuid());
2421: close(newsock);
2422: return;
2423: }
1.424 djm 2424: nc = channel_new(ssh, "mux-control", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2425: newsock, newsock, -1, c->local_window_max,
2426: c->local_maxpacket, 0, "mux-control", 1);
2427: nc->mux_rcb = c->mux_rcb;
1.403 djm 2428: debug3_f("new mux channel %d fd %d", nc->self, nc->sock);
1.302 djm 2429: /* establish state */
1.367 djm 2430: nc->mux_rcb(ssh, nc);
1.302 djm 2431: /* mux state transitions must not elicit protocol messages */
2432: nc->flags |= CHAN_LOCAL;
2433: }
2434:
1.127 itojun 2435: static void
1.367 djm 2436: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2437: {
1.367 djm 2438: chan_fn **pre, **post;
2439:
2440: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
1.406 djm 2441: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
1.403 djm 2442: fatal_f("allocation failed");
1.367 djm 2443:
2444: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2445: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2446: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2447: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2448: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2449: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2450: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2451: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2452: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2453: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2454: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2455: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2456: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2457:
2458: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2459: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2460: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2461: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2462: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2463: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2464: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2465: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2466: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2467: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2468: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2469: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2470:
1.367 djm 2471: sc->channel_pre = pre;
2472: sc->channel_post = post;
1.44 markus 2473: }
2474:
1.140 markus 2475: /* gc dead channels */
2476: static void
1.367 djm 2477: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2478: {
2479: if (c == NULL)
2480: return;
2481: if (c->detach_user != NULL) {
1.367 djm 2482: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2483: return;
1.385 djm 2484:
1.194 markus 2485: debug2("channel %d: gc: notify user", c->self);
1.423 djm 2486: c->detach_user(ssh, c->self, 0, NULL);
1.140 markus 2487: /* if we still have a callback */
2488: if (c->detach_user != NULL)
2489: return;
1.194 markus 2490: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2491: }
1.367 djm 2492: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2493: return;
1.194 markus 2494: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2495: channel_free(ssh, c);
1.140 markus 2496: }
2497:
1.367 djm 2498: enum channel_table { CHAN_PRE, CHAN_POST };
2499:
1.127 itojun 2500: static void
1.422 djm 2501: channel_handler(struct ssh *ssh, int table, struct timespec *timeout)
1.41 markus 2502: {
1.367 djm 2503: struct ssh_channels *sc = ssh->chanctxt;
2504: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2505: u_int i, oalloc;
1.41 markus 2506: Channel *c;
1.317 djm 2507: time_t now;
1.25 markus 2508:
1.322 dtucker 2509: now = monotime();
1.367 djm 2510: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2511: c = sc->channels[i];
1.113 markus 2512: if (c == NULL)
1.41 markus 2513: continue;
1.417 djm 2514: /* Try to keep IO going while rekeying */
2515: if (ssh_packet_is_rekeying(ssh) && c->type != SSH_CHANNEL_OPEN)
2516: continue;
1.299 markus 2517: if (c->delayed) {
1.367 djm 2518: if (table == CHAN_PRE)
1.299 markus 2519: c->delayed = 0;
2520: else
2521: continue;
2522: }
1.317 djm 2523: if (ftab[c->type] != NULL) {
1.426 djm 2524: if (table == CHAN_PRE &&
2525: c->type == SSH_CHANNEL_OPEN &&
2526: c->inactive_deadline != 0 && c->lastused != 0 &&
2527: now >= c->lastused + c->inactive_deadline) {
2528: /* channel closed for inactivity */
2529: verbose("channel %d: closing after %u seconds "
2530: "of inactivity", c->self,
2531: c->inactive_deadline);
2532: channel_force_close(ssh, c, 1);
2533: } else if (c->notbefore <= now) {
2534: /* Run handlers that are not paused. */
1.410 djm 2535: (*ftab[c->type])(ssh, c);
1.426 djm 2536: /* inactivity timeouts must interrupt poll() */
2537: if (timeout != NULL &&
2538: c->type == SSH_CHANNEL_OPEN &&
2539: c->lastused != 0 &&
2540: c->inactive_deadline != 0) {
2541: ptimeout_deadline_monotime(timeout,
2542: c->lastused + c->inactive_deadline);
2543: }
2544: } else if (timeout != NULL) {
1.317 djm 2545: /*
1.426 djm 2546: * Arrange for poll() wakeup when channel pause
1.422 djm 2547: * timer expires.
1.317 djm 2548: */
1.422 djm 2549: ptimeout_deadline_monotime(timeout,
2550: c->notbefore);
1.317 djm 2551: }
2552: }
1.367 djm 2553: channel_garbage_collect(ssh, c);
1.1 deraadt 2554: }
2555: }
2556:
1.121 markus 2557: /*
1.411 djm 2558: * Create sockets before preparing IO.
1.372 markus 2559: * This is necessary for things that need to happen after reading
1.411 djm 2560: * the network-input but need to be completed before IO event setup, e.g.
2561: * because they may create new channels.
1.372 markus 2562: */
2563: static void
1.411 djm 2564: channel_before_prepare_io(struct ssh *ssh)
1.372 markus 2565: {
2566: struct ssh_channels *sc = ssh->chanctxt;
2567: Channel *c;
2568: u_int i, oalloc;
2569:
2570: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2571: c = sc->channels[i];
2572: if (c == NULL)
2573: continue;
2574: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
1.411 djm 2575: channel_before_prepare_io_rdynamic(ssh, c);
2576: }
2577: }
2578:
2579: static void
2580: dump_channel_poll(const char *func, const char *what, Channel *c,
2581: u_int pollfd_offset, struct pollfd *pfd)
2582: {
2583: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2584: debug3("%s: channel %d: %s r%d w%d e%d s%d c->pfds [ %d %d %d %d ] "
2585: "io_want 0x%02x io_ready 0x%02x pfd[%u].fd=%d "
2586: "pfd.ev 0x%02x pfd.rev 0x%02x", func, c->self, what,
2587: c->rfd, c->wfd, c->efd, c->sock,
2588: c->pfds[0], c->pfds[1], c->pfds[2], c->pfds[3],
2589: c->io_want, c->io_ready,
2590: pollfd_offset, pfd->fd, pfd->events, pfd->revents);
1.411 djm 2591: #endif
2592: }
2593:
2594: /* Prepare pollfd entries for a single channel */
2595: static void
2596: channel_prepare_pollfd(Channel *c, u_int *next_pollfd,
2597: struct pollfd *pfd, u_int npfd)
2598: {
1.415 djm 2599: u_int ev, p = *next_pollfd;
1.411 djm 2600:
2601: if (c == NULL)
2602: return;
2603: if (p + 4 > npfd) {
2604: /* Shouldn't happen */
2605: fatal_f("channel %d: bad pfd offset %u (max %u)",
2606: c->self, p, npfd);
2607: }
1.415 djm 2608: c->pfds[0] = c->pfds[1] = c->pfds[2] = c->pfds[3] = -1;
1.411 djm 2609: /*
2610: * prepare c->rfd
2611: *
2612: * This is a special case, since c->rfd might be the same as
2613: * c->wfd, c->efd and/or c->sock. Handle those here if they want
2614: * IO too.
2615: */
2616: if (c->rfd != -1) {
1.415 djm 2617: ev = 0;
1.411 djm 2618: if ((c->io_want & SSH_CHAN_IO_RFD) != 0)
1.415 djm 2619: ev |= POLLIN;
1.411 djm 2620: /* rfd == wfd */
1.415 djm 2621: if (c->wfd == c->rfd) {
2622: if ((c->io_want & SSH_CHAN_IO_WFD) != 0)
2623: ev |= POLLOUT;
2624: }
1.411 djm 2625: /* rfd == efd */
1.415 djm 2626: if (c->efd == c->rfd) {
2627: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
2628: ev |= POLLIN;
2629: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
2630: ev |= POLLOUT;
2631: }
1.411 djm 2632: /* rfd == sock */
1.415 djm 2633: if (c->sock == c->rfd) {
2634: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
2635: ev |= POLLIN;
2636: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
2637: ev |= POLLOUT;
2638: }
2639: /* Pack a pfd entry if any event armed for this fd */
2640: if (ev != 0) {
2641: c->pfds[0] = p;
2642: pfd[p].fd = c->rfd;
2643: pfd[p].events = ev;
2644: dump_channel_poll(__func__, "rfd", c, p, &pfd[p]);
2645: p++;
2646: }
1.411 djm 2647: }
1.415 djm 2648: /* prepare c->wfd if wanting IO and not already handled above */
1.411 djm 2649: if (c->wfd != -1 && c->rfd != c->wfd) {
1.415 djm 2650: ev = 0;
2651: if ((c->io_want & SSH_CHAN_IO_WFD))
2652: ev |= POLLOUT;
2653: /* Pack a pfd entry if any event armed for this fd */
2654: if (ev != 0) {
2655: c->pfds[1] = p;
2656: pfd[p].fd = c->wfd;
2657: pfd[p].events = ev;
2658: dump_channel_poll(__func__, "wfd", c, p, &pfd[p]);
2659: p++;
2660: }
1.411 djm 2661: }
1.415 djm 2662: /* prepare c->efd if wanting IO and not already handled above */
1.411 djm 2663: if (c->efd != -1 && c->rfd != c->efd) {
1.415 djm 2664: ev = 0;
1.411 djm 2665: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
1.415 djm 2666: ev |= POLLIN;
1.411 djm 2667: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
1.415 djm 2668: ev |= POLLOUT;
2669: /* Pack a pfd entry if any event armed for this fd */
2670: if (ev != 0) {
2671: c->pfds[2] = p;
2672: pfd[p].fd = c->efd;
2673: pfd[p].events = ev;
2674: dump_channel_poll(__func__, "efd", c, p, &pfd[p]);
2675: p++;
2676: }
1.411 djm 2677: }
1.415 djm 2678: /* prepare c->sock if wanting IO and not already handled above */
1.411 djm 2679: if (c->sock != -1 && c->rfd != c->sock) {
1.415 djm 2680: ev = 0;
1.411 djm 2681: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
1.415 djm 2682: ev |= POLLIN;
1.411 djm 2683: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
1.415 djm 2684: ev |= POLLOUT;
2685: /* Pack a pfd entry if any event armed for this fd */
2686: if (ev != 0) {
2687: c->pfds[3] = p;
2688: pfd[p].fd = c->sock;
2689: pfd[p].events = 0;
2690: dump_channel_poll(__func__, "sock", c, p, &pfd[p]);
2691: p++;
2692: }
1.372 markus 2693: }
1.411 djm 2694: *next_pollfd = p;
1.372 markus 2695: }
2696:
1.411 djm 2697: /* * Allocate/prepare poll structure */
1.49 markus 2698: void
1.411 djm 2699: channel_prepare_poll(struct ssh *ssh, struct pollfd **pfdp, u_int *npfd_allocp,
1.422 djm 2700: u_int *npfd_activep, u_int npfd_reserved, struct timespec *timeout)
1.41 markus 2701: {
1.410 djm 2702: struct ssh_channels *sc = ssh->chanctxt;
1.411 djm 2703: u_int i, oalloc, p, npfd = npfd_reserved;
2704:
2705: channel_before_prepare_io(ssh); /* might create a new channel */
1.416 djm 2706: /* clear out I/O flags from last poll */
2707: for (i = 0; i < sc->channels_alloc; i++) {
2708: if (sc->channels[i] == NULL)
2709: continue;
2710: sc->channels[i]->io_want = sc->channels[i]->io_ready = 0;
2711: }
1.411 djm 2712: /* Allocate 4x pollfd for each channel (rfd, wfd, efd, sock) */
2713: if (sc->channels_alloc >= (INT_MAX / 4) - npfd_reserved)
2714: fatal_f("too many channels"); /* shouldn't happen */
1.417 djm 2715: npfd += sc->channels_alloc * 4;
1.411 djm 2716: if (npfd > *npfd_allocp) {
2717: *pfdp = xrecallocarray(*pfdp, *npfd_allocp,
2718: npfd, sizeof(**pfdp));
2719: *npfd_allocp = npfd;
2720: }
2721: *npfd_activep = npfd_reserved;
2722: oalloc = sc->channels_alloc;
1.372 markus 2723:
1.422 djm 2724: channel_handler(ssh, CHAN_PRE, timeout);
1.84 markus 2725:
1.411 djm 2726: if (oalloc != sc->channels_alloc) {
2727: /* shouldn't happen */
2728: fatal_f("channels_alloc changed during CHAN_PRE "
2729: "(was %u, now %u)", oalloc, sc->channels_alloc);
2730: }
1.84 markus 2731:
1.411 djm 2732: /* Prepare pollfd */
2733: p = npfd_reserved;
2734: for (i = 0; i < sc->channels_alloc; i++)
2735: channel_prepare_pollfd(sc->channels[i], &p, *pfdp, npfd);
2736: *npfd_activep = p;
2737: }
2738:
2739: static void
1.415 djm 2740: fd_ready(Channel *c, int p, struct pollfd *pfds, u_int npfd, int fd,
1.411 djm 2741: const char *what, u_int revents_mask, u_int ready)
2742: {
2743: struct pollfd *pfd = &pfds[p];
1.410 djm 2744:
1.411 djm 2745: if (fd == -1)
2746: return;
1.415 djm 2747: if (p == -1 || (u_int)p >= npfd)
2748: fatal_f("channel %d: bad pfd %d (max %u)", c->self, p, npfd);
1.411 djm 2749: dump_channel_poll(__func__, what, c, p, pfd);
2750: if (pfd->fd != fd) {
2751: fatal("channel %d: inconsistent %s fd=%d pollfd[%u].fd %d "
2752: "r%d w%d e%d s%d", c->self, what, fd, p, pfd->fd,
2753: c->rfd, c->wfd, c->efd, c->sock);
2754: }
2755: if ((pfd->revents & POLLNVAL) != 0) {
2756: fatal("channel %d: invalid %s pollfd[%u].fd %d r%d w%d e%d s%d",
2757: c->self, what, p, pfd->fd, c->rfd, c->wfd, c->efd, c->sock);
1.410 djm 2758: }
1.411 djm 2759: if ((pfd->revents & (revents_mask|POLLHUP|POLLERR)) != 0)
2760: c->io_ready |= ready & c->io_want;
1.41 markus 2761: }
2762:
1.121 markus 2763: /*
1.411 djm 2764: * After poll, perform any appropriate operations for channels which have
1.121 markus 2765: * events pending.
2766: */
1.49 markus 2767: void
1.411 djm 2768: channel_after_poll(struct ssh *ssh, struct pollfd *pfd, u_int npfd)
1.41 markus 2769: {
1.410 djm 2770: struct ssh_channels *sc = ssh->chanctxt;
1.415 djm 2771: u_int i;
2772: int p;
1.410 djm 2773: Channel *c;
2774:
1.411 djm 2775: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2776: for (p = 0; p < (int)npfd; p++) {
1.411 djm 2777: if (pfd[p].revents == 0)
2778: continue;
2779: debug_f("pfd[%u].fd %d rev 0x%04x",
2780: p, pfd[p].fd, pfd[p].revents);
2781: }
2782: #endif
2783:
2784: /* Convert pollfd into c->io_ready */
2785: for (i = 0; i < sc->channels_alloc; i++) {
1.410 djm 2786: c = sc->channels[i];
1.415 djm 2787: if (c == NULL)
1.410 djm 2788: continue;
1.411 djm 2789: /* if rfd is shared with efd/sock then wfd should be too */
2790: if (c->rfd != -1 && c->wfd != -1 && c->rfd != c->wfd &&
2791: (c->rfd == c->efd || c->rfd == c->sock)) {
2792: /* Shouldn't happen */
2793: fatal_f("channel %d: unexpected fds r%d w%d e%d s%d",
2794: c->self, c->rfd, c->wfd, c->efd, c->sock);
2795: }
1.410 djm 2796: c->io_ready = 0;
1.411 djm 2797: /* rfd, potentially shared with wfd, efd and sock */
1.415 djm 2798: if (c->rfd != -1 && (p = c->pfds[0]) != -1) {
2799: fd_ready(c, p, pfd, npfd, c->rfd,
2800: "rfd", POLLIN, SSH_CHAN_IO_RFD);
1.411 djm 2801: if (c->rfd == c->wfd) {
1.415 djm 2802: fd_ready(c, p, pfd, npfd, c->wfd,
2803: "wfd/r", POLLOUT, SSH_CHAN_IO_WFD);
1.411 djm 2804: }
2805: if (c->rfd == c->efd) {
1.415 djm 2806: fd_ready(c, p, pfd, npfd, c->efd,
2807: "efdr/r", POLLIN, SSH_CHAN_IO_EFD_R);
2808: fd_ready(c, p, pfd, npfd, c->efd,
2809: "efdw/r", POLLOUT, SSH_CHAN_IO_EFD_W);
1.411 djm 2810: }
2811: if (c->rfd == c->sock) {
1.415 djm 2812: fd_ready(c, p, pfd, npfd, c->sock,
2813: "sockr/r", POLLIN, SSH_CHAN_IO_SOCK_R);
2814: fd_ready(c, p, pfd, npfd, c->sock,
2815: "sockw/r", POLLOUT, SSH_CHAN_IO_SOCK_W);
1.411 djm 2816: }
1.415 djm 2817: dump_channel_poll(__func__, "rfd", c, p, pfd);
1.411 djm 2818: }
2819: /* wfd */
1.415 djm 2820: if (c->wfd != -1 && c->wfd != c->rfd &&
2821: (p = c->pfds[1]) != -1) {
2822: fd_ready(c, p, pfd, npfd, c->wfd,
2823: "wfd", POLLOUT, SSH_CHAN_IO_WFD);
2824: dump_channel_poll(__func__, "wfd", c, p, pfd);
1.411 djm 2825: }
2826: /* efd */
1.415 djm 2827: if (c->efd != -1 && c->efd != c->rfd &&
2828: (p = c->pfds[2]) != -1) {
2829: fd_ready(c, p, pfd, npfd, c->efd,
2830: "efdr", POLLIN, SSH_CHAN_IO_EFD_R);
2831: fd_ready(c, p, pfd, npfd, c->efd,
2832: "efdw", POLLOUT, SSH_CHAN_IO_EFD_W);
2833: dump_channel_poll(__func__, "efd", c, p, pfd);
1.411 djm 2834: }
2835: /* sock */
1.415 djm 2836: if (c->sock != -1 && c->sock != c->rfd &&
2837: (p = c->pfds[3]) != -1) {
2838: fd_ready(c, p, pfd, npfd, c->sock,
2839: "sockr", POLLIN, SSH_CHAN_IO_SOCK_R);
2840: fd_ready(c, p, pfd, npfd, c->sock,
2841: "sockw", POLLOUT, SSH_CHAN_IO_SOCK_W);
2842: dump_channel_poll(__func__, "sock", c, p, pfd);
1.411 djm 2843: }
1.410 djm 2844: }
2845: channel_handler(ssh, CHAN_POST, NULL);
1.367 djm 2846: }
2847:
2848: /*
2849: * Enqueue data for channels with open or draining c->input.
2850: */
2851: static void
2852: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2853: {
1.373 djm 2854: size_t len, plen;
2855: const u_char *pkt;
1.367 djm 2856: int r;
2857:
2858: if ((len = sshbuf_len(c->input)) == 0) {
2859: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2860: /*
2861: * input-buffer is empty and read-socket shutdown:
2862: * tell peer, that we will not send more data:
2863: * send IEOF.
2864: * hack for extended data: delay EOF if EFD still
2865: * in use.
2866: */
2867: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2868: debug2("channel %d: "
2869: "ibuf_empty delayed efd %d/(%zu)",
2870: c->self, c->efd, sshbuf_len(c->extended));
2871: else
2872: chan_ibuf_empty(ssh, c);
2873: }
2874: return;
2875: }
2876:
1.368 djm 2877: if (!c->have_remote_id)
1.403 djm 2878: fatal_f("channel %d: no remote id", c->self);
1.368 djm 2879:
1.367 djm 2880: if (c->datagram) {
2881: /* Check datagram will fit; drop if not */
1.373 djm 2882: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
1.403 djm 2883: fatal_fr(r, "channel %i: get datagram", c->self);
1.367 djm 2884: /*
2885: * XXX this does tail-drop on the datagram queue which is
2886: * usually suboptimal compared to head-drop. Better to have
2887: * backpressure at read time? (i.e. read + discard)
2888: */
1.373 djm 2889: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2890: debug("channel %d: datagram too big", c->self);
2891: return;
2892: }
2893: /* Enqueue it */
2894: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2895: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2896: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.403 djm 2897: (r = sshpkt_send(ssh)) != 0)
2898: fatal_fr(r, "channel %i: send datagram", c->self);
1.373 djm 2899: c->remote_window -= plen;
1.367 djm 2900: return;
2901: }
2902:
2903: /* Enqueue packet for buffered data. */
2904: if (len > c->remote_window)
2905: len = c->remote_window;
2906: if (len > c->remote_maxpacket)
2907: len = c->remote_maxpacket;
2908: if (len == 0)
2909: return;
2910: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2911: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2912: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
1.403 djm 2913: (r = sshpkt_send(ssh)) != 0)
2914: fatal_fr(r, "channel %i: send data", c->self);
1.367 djm 2915: if ((r = sshbuf_consume(c->input, len)) != 0)
1.403 djm 2916: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2917: c->remote_window -= len;
1.41 markus 2918: }
2919:
1.367 djm 2920: /*
2921: * Enqueue data for channels with open c->extended in read mode.
2922: */
2923: static void
2924: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2925: {
2926: size_t len;
2927: int r;
2928:
2929: if ((len = sshbuf_len(c->extended)) == 0)
2930: return;
2931:
2932: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2933: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2934: if (len > c->remote_window)
2935: len = c->remote_window;
2936: if (len > c->remote_maxpacket)
2937: len = c->remote_maxpacket;
2938: if (len == 0)
2939: return;
1.368 djm 2940: if (!c->have_remote_id)
1.403 djm 2941: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2942: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2943: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2944: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2945: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
1.403 djm 2946: (r = sshpkt_send(ssh)) != 0)
2947: fatal_fr(r, "channel %i: data", c->self);
1.367 djm 2948: if ((r = sshbuf_consume(c->extended, len)) != 0)
1.403 djm 2949: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2950: c->remote_window -= len;
2951: debug2("channel %d: sent ext data %zu", c->self, len);
2952: }
1.121 markus 2953:
1.84 markus 2954: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2955: void
1.367 djm 2956: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2957: {
1.367 djm 2958: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2959: Channel *c;
1.367 djm 2960: u_int i;
1.1 deraadt 2961:
1.367 djm 2962: for (i = 0; i < sc->channels_alloc; i++) {
2963: c = sc->channels[i];
1.113 markus 2964: if (c == NULL)
2965: continue;
1.37 markus 2966:
1.121 markus 2967: /*
2968: * We are only interested in channels that can have buffered
2969: * incoming data.
2970: */
1.358 djm 2971: if (c->type != SSH_CHANNEL_OPEN)
2972: continue;
2973: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2974: /* XXX is this true? */
1.367 djm 2975: debug3("channel %d: will not send data after close",
2976: c->self);
1.44 markus 2977: continue;
2978: }
1.25 markus 2979:
2980: /* Get the amount of buffered data for this channel. */
1.367 djm 2981: if (c->istate == CHAN_INPUT_OPEN ||
2982: c->istate == CHAN_INPUT_WAIT_DRAIN)
2983: channel_output_poll_input_open(ssh, c);
1.44 markus 2984: /* Send extended data, i.e. stderr */
1.358 djm 2985: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2986: c->extended_usage == CHAN_EXTENDED_READ)
2987: channel_output_poll_extended_read(ssh, c);
1.25 markus 2988: }
1.1 deraadt 2989: }
2990:
1.354 markus 2991: /* -- mux proxy support */
2992:
2993: /*
2994: * When multiplexing channel messages for mux clients we have to deal
2995: * with downstream messages from the mux client and upstream messages
2996: * from the ssh server:
2997: * 1) Handling downstream messages is straightforward and happens
2998: * in channel_proxy_downstream():
2999: * - We forward all messages (mostly) unmodified to the server.
3000: * - However, in order to route messages from upstream to the correct
3001: * downstream client, we have to replace the channel IDs used by the
3002: * mux clients with a unique channel ID because the mux clients might
3003: * use conflicting channel IDs.
3004: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
3005: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
3006: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
3007: * with the newly allocated channel ID.
3008: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 3009: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 3010: * is then translated back to the original mux client ID.
3011: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
3012: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
3013: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
3014: * downstream mux client are removed.
3015: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
3016: * requires more work, because they are not addressed to a specific
3017: * channel. E.g. client_request_forwarded_tcpip() needs to figure
3018: * out whether the request is addressed to the local client or a
3019: * specific downstream client based on the listen-address/port.
1.380 djm 3020: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 3021: * not supported as the matching session/channel cannot be identified
3022: * easily.
3023: */
3024:
3025: /*
3026: * receive packets from downstream mux clients:
3027: * channel callback fired on read from mux client, creates
3028: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
3029: * on channel creation.
3030: */
3031: int
1.367 djm 3032: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 3033: {
3034: Channel *c = NULL;
3035: struct sshbuf *original = NULL, *modified = NULL;
3036: const u_char *cp;
3037: char *ctype = NULL, *listen_host = NULL;
3038: u_char type;
3039: size_t have;
1.370 djm 3040: int ret = -1, r;
1.355 djm 3041: u_int id, remote_id, listen_port;
1.354 markus 3042:
1.367 djm 3043: /* sshbuf_dump(downstream->input, stderr); */
3044: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 3045: != 0) {
1.403 djm 3046: error_fr(r, "parse");
1.354 markus 3047: return -1;
3048: }
3049: if (have < 2) {
1.403 djm 3050: error_f("short message");
1.354 markus 3051: return -1;
3052: }
3053: type = cp[1];
3054: /* skip padlen + type */
3055: cp += 2;
3056: have -= 2;
3057: if (ssh_packet_log_type(type))
1.403 djm 3058: debug3_f("channel %u: down->up: type %u",
1.354 markus 3059: downstream->self, type);
3060:
3061: switch (type) {
3062: case SSH2_MSG_CHANNEL_OPEN:
3063: if ((original = sshbuf_from(cp, have)) == NULL ||
3064: (modified = sshbuf_new()) == NULL) {
1.403 djm 3065: error_f("alloc");
1.354 markus 3066: goto out;
3067: }
3068: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
3069: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 3070: error_fr(r, "parse");
1.354 markus 3071: goto out;
3072: }
1.424 djm 3073: c = channel_new(ssh, "mux-proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 3074: -1, -1, -1, 0, 0, 0, ctype, 1);
1.354 markus 3075: c->mux_ctx = downstream; /* point to mux client */
3076: c->mux_downstream_id = id; /* original downstream id */
3077: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
3078: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
3079: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 3080: error_fr(r, "compose");
1.367 djm 3081: channel_free(ssh, c);
1.354 markus 3082: goto out;
3083: }
3084: break;
3085: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3086: /*
3087: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
3088: * need to parse 'remote_id' instead of 'ctype'.
3089: */
3090: if ((original = sshbuf_from(cp, have)) == NULL ||
3091: (modified = sshbuf_new()) == NULL) {
1.403 djm 3092: error_f("alloc");
1.354 markus 3093: goto out;
3094: }
3095: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
3096: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 3097: error_fr(r, "parse");
1.354 markus 3098: goto out;
3099: }
1.424 djm 3100: c = channel_new(ssh, "mux-proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 3101: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
1.354 markus 3102: c->mux_ctx = downstream; /* point to mux client */
3103: c->mux_downstream_id = id;
3104: c->remote_id = remote_id;
1.368 djm 3105: c->have_remote_id = 1;
1.354 markus 3106: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
3107: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
3108: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 3109: error_fr(r, "compose");
1.367 djm 3110: channel_free(ssh, c);
1.354 markus 3111: goto out;
3112: }
3113: break;
3114: case SSH2_MSG_GLOBAL_REQUEST:
3115: if ((original = sshbuf_from(cp, have)) == NULL) {
1.403 djm 3116: error_f("alloc");
1.354 markus 3117: goto out;
3118: }
3119: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
1.403 djm 3120: error_fr(r, "parse");
1.354 markus 3121: goto out;
3122: }
3123: if (strcmp(ctype, "tcpip-forward") != 0) {
1.403 djm 3124: error_f("unsupported request %s", ctype);
1.354 markus 3125: goto out;
3126: }
3127: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
3128: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
3129: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
1.403 djm 3130: error_fr(r, "parse");
1.354 markus 3131: goto out;
3132: }
1.355 djm 3133: if (listen_port > 65535) {
1.403 djm 3134: error_f("tcpip-forward for %s: bad port %u",
3135: listen_host, listen_port);
1.355 djm 3136: goto out;
3137: }
1.354 markus 3138: /* Record that connection to this host/port is permitted. */
1.381 djm 3139: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 3140: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 3141: listen_host = NULL;
3142: break;
3143: case SSH2_MSG_CHANNEL_CLOSE:
3144: if (have < 4)
3145: break;
3146: remote_id = PEEK_U32(cp);
1.367 djm 3147: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 3148: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 3149: channel_free(ssh, c);
1.354 markus 3150: else
3151: c->flags |= CHAN_CLOSE_SENT;
3152: }
3153: break;
3154: }
3155: if (modified) {
3156: if ((r = sshpkt_start(ssh, type)) != 0 ||
3157: (r = sshpkt_putb(ssh, modified)) != 0 ||
3158: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3159: error_fr(r, "send");
1.354 markus 3160: goto out;
3161: }
3162: } else {
3163: if ((r = sshpkt_start(ssh, type)) != 0 ||
3164: (r = sshpkt_put(ssh, cp, have)) != 0 ||
3165: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3166: error_fr(r, "send");
1.354 markus 3167: goto out;
3168: }
3169: }
3170: ret = 0;
3171: out:
3172: free(ctype);
3173: free(listen_host);
3174: sshbuf_free(original);
3175: sshbuf_free(modified);
3176: return ret;
3177: }
3178:
3179: /*
3180: * receive packets from upstream server and de-multiplex packets
3181: * to correct downstream:
3182: * implemented as a helper for channel input handlers,
3183: * replaces local (proxy) channel ID with downstream channel ID.
3184: */
3185: int
1.363 markus 3186: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 3187: {
3188: struct sshbuf *b = NULL;
3189: Channel *downstream;
3190: const u_char *cp = NULL;
3191: size_t len;
3192: int r;
3193:
3194: /*
3195: * When receiving packets from the peer we need to check whether we
3196: * need to forward the packets to the mux client. In this case we
1.380 djm 3197: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 3198: * so we can cleanup the channel.
3199: */
3200: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
3201: return 0;
3202: if ((downstream = c->mux_ctx) == NULL)
3203: return 0;
3204: switch (type) {
3205: case SSH2_MSG_CHANNEL_CLOSE:
3206: case SSH2_MSG_CHANNEL_DATA:
3207: case SSH2_MSG_CHANNEL_EOF:
3208: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
3209: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3210: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
3211: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
3212: case SSH2_MSG_CHANNEL_SUCCESS:
3213: case SSH2_MSG_CHANNEL_FAILURE:
3214: case SSH2_MSG_CHANNEL_REQUEST:
3215: break;
3216: default:
1.403 djm 3217: debug2_f("channel %u: unsupported type %u", c->self, type);
1.354 markus 3218: return 0;
3219: }
3220: if ((b = sshbuf_new()) == NULL) {
1.403 djm 3221: error_f("alloc reply");
1.354 markus 3222: goto out;
3223: }
3224: /* get remaining payload (after id) */
3225: cp = sshpkt_ptr(ssh, &len);
3226: if (cp == NULL) {
1.403 djm 3227: error_f("no packet");
1.354 markus 3228: goto out;
3229: }
3230: /* translate id and send to muxclient */
3231: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
3232: (r = sshbuf_put_u8(b, type)) != 0 ||
3233: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
3234: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 3235: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.403 djm 3236: error_fr(r, "compose muxclient");
1.354 markus 3237: goto out;
3238: }
3239: /* sshbuf_dump(b, stderr); */
3240: if (ssh_packet_log_type(type))
1.403 djm 3241: debug3_f("channel %u: up->down: type %u", c->self, type);
1.354 markus 3242: out:
3243: /* update state */
3244: switch (type) {
3245: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3246: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 3247: if (cp && len > 4) {
1.354 markus 3248: c->remote_id = PEEK_U32(cp);
1.368 djm 3249: c->have_remote_id = 1;
3250: }
1.354 markus 3251: break;
3252: case SSH2_MSG_CHANNEL_CLOSE:
3253: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 3254: channel_free(ssh, c);
1.354 markus 3255: else
3256: c->flags |= CHAN_CLOSE_RCVD;
3257: break;
3258: }
3259: sshbuf_free(b);
3260: return 1;
3261: }
1.121 markus 3262:
3263: /* -- protocol input */
1.249 djm 3264:
1.367 djm 3265: /* Parse a channel ID from the current packet */
3266: static int
3267: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
3268: {
3269: u_int32_t id;
3270: int r;
3271:
3272: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
1.403 djm 3273: error_r(r, "%s: parse id", where);
1.367 djm 3274: ssh_packet_disconnect(ssh, "Invalid %s message", what);
3275: }
3276: if (id > INT_MAX) {
1.403 djm 3277: error_r(r, "%s: bad channel id %u", where, id);
1.367 djm 3278: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
3279: }
3280: return (int)id;
3281: }
3282:
3283: /* Lookup a channel from an ID in the current packet */
3284: static Channel *
3285: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
3286: {
3287: int id = channel_parse_id(ssh, where, what);
3288: Channel *c;
3289:
3290: if ((c = channel_lookup(ssh, id)) == NULL) {
3291: ssh_packet_disconnect(ssh,
3292: "%s packet referred to nonexistent channel %d", what, id);
3293: }
3294: return c;
3295: }
3296:
1.339 markus 3297: int
1.363 markus 3298: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3299: {
1.332 djm 3300: const u_char *data;
1.367 djm 3301: size_t data_len, win_len;
3302: Channel *c = channel_from_packet_id(ssh, __func__, "data");
3303: int r;
1.25 markus 3304:
1.363 markus 3305: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3306: return 0;
1.25 markus 3307:
3308: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 3309: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 3310: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
3311: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 3312: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 3313: return 0;
1.37 markus 3314:
1.25 markus 3315: /* Get the data. */
1.389 djm 3316: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3317: (r = sshpkt_get_end(ssh)) != 0)
1.403 djm 3318: fatal_fr(r, "channel %i: get data", c->self);
1.367 djm 3319:
1.309 djm 3320: win_len = data_len;
3321: if (c->datagram)
3322: win_len += 4; /* string length header */
1.200 markus 3323:
3324: /*
1.367 djm 3325: * The sending side reduces its window as it sends data, so we
3326: * must 'fake' consumption of the data in order to ensure that window
3327: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 3328: */
1.358 djm 3329: if (c->ostate != CHAN_OUTPUT_OPEN) {
3330: c->local_window -= win_len;
3331: c->local_consumed += win_len;
1.339 markus 3332: return 0;
1.200 markus 3333: }
1.41 markus 3334:
1.358 djm 3335: if (win_len > c->local_maxpacket) {
1.367 djm 3336: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 3337: c->self, win_len, c->local_maxpacket);
1.367 djm 3338: return 0;
1.358 djm 3339: }
3340: if (win_len > c->local_window) {
1.367 djm 3341: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 3342: c->self, win_len, c->local_window);
3343: return 0;
1.44 markus 3344: }
1.358 djm 3345: c->local_window -= win_len;
3346:
1.367 djm 3347: if (c->datagram) {
3348: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
1.403 djm 3349: fatal_fr(r, "channel %i: append datagram", c->self);
1.367 djm 3350: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
1.403 djm 3351: fatal_fr(r, "channel %i: append data", c->self);
1.367 djm 3352:
1.339 markus 3353: return 0;
1.1 deraadt 3354: }
1.121 markus 3355:
1.339 markus 3356: int
1.363 markus 3357: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 3358: {
1.367 djm 3359: const u_char *data;
3360: size_t data_len;
3361: u_int32_t tcode;
3362: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
3363: int r;
1.44 markus 3364:
1.363 markus 3365: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3366: return 0;
1.44 markus 3367: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 3368: logit("channel %d: ext data for non open", c->self);
1.339 markus 3369: return 0;
1.172 markus 3370: }
3371: if (c->flags & CHAN_EOF_RCVD) {
1.404 djm 3372: if (ssh->compat & SSH_BUG_EXTEOF)
1.367 djm 3373: debug("channel %d: accepting ext data after eof",
3374: c->self);
1.172 markus 3375: else
1.367 djm 3376: ssh_packet_disconnect(ssh, "Received extended_data "
3377: "after EOF on channel %d.", c->self);
3378: }
3379:
3380: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
1.403 djm 3381: error_fr(r, "parse tcode");
1.367 djm 3382: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3383: }
3384: if (c->efd == -1 ||
3385: c->extended_usage != CHAN_EXTENDED_WRITE ||
3386: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3387: logit("channel %d: bad ext data", c->self);
1.339 markus 3388: return 0;
1.44 markus 3389: }
1.389 djm 3390: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3391: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3392: error_fr(r, "parse data");
1.367 djm 3393: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3394: }
3395:
1.44 markus 3396: if (data_len > c->local_window) {
1.367 djm 3397: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3398: c->self, data_len, c->local_window);
1.339 markus 3399: return 0;
1.44 markus 3400: }
1.367 djm 3401: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3402: /* XXX sshpkt_getb? */
3403: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
1.403 djm 3404: error_fr(r, "append");
1.44 markus 3405: c->local_window -= data_len;
1.339 markus 3406: return 0;
1.44 markus 3407: }
3408:
1.339 markus 3409: int
1.363 markus 3410: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3411: {
1.367 djm 3412: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3413: int r;
1.367 djm 3414:
1.389 djm 3415: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3416: error_fr(r, "parse data");
1.389 djm 3417: ssh_packet_disconnect(ssh, "Invalid ieof message");
3418: }
1.41 markus 3419:
1.363 markus 3420: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3421: return 0;
1.367 djm 3422: chan_rcvd_ieof(ssh, c);
1.133 markus 3423:
3424: /* XXX force input close */
1.156 markus 3425: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3426: debug("channel %d: FORCE input drain", c->self);
3427: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3428: if (sshbuf_len(c->input) == 0)
3429: chan_ibuf_empty(ssh, c);
1.133 markus 3430: }
1.339 markus 3431: return 0;
1.41 markus 3432: }
1.1 deraadt 3433:
1.339 markus 3434: int
1.363 markus 3435: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3436: {
1.367 djm 3437: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3438: int r;
1.151 markus 3439:
1.363 markus 3440: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3441: return 0;
1.389 djm 3442: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3443: error_fr(r, "parse data");
1.389 djm 3444: ssh_packet_disconnect(ssh, "Invalid oclose message");
3445: }
1.367 djm 3446: chan_rcvd_oclose(ssh, c);
1.339 markus 3447: return 0;
1.1 deraadt 3448: }
3449:
1.339 markus 3450: int
1.363 markus 3451: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3452: {
1.367 djm 3453: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3454: u_int32_t remote_window, remote_maxpacket;
3455: int r;
1.25 markus 3456:
1.363 markus 3457: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3458: return 0;
3459: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3460: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3461: "non-opening channel %d.", c->self);
3462: /*
3463: * Record the remote channel number and mark that the channel
3464: * is now open.
3465: */
1.368 djm 3466: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3467: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3468: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3469: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3470: error_fr(r, "window/maxpacket");
1.389 djm 3471: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3472: }
3473:
1.368 djm 3474: c->have_remote_id = 1;
1.367 djm 3475: c->remote_window = remote_window;
3476: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3477: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3478: if (c->open_confirm) {
1.403 djm 3479: debug2_f("channel %d: callback start", c->self);
1.367 djm 3480: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
1.403 djm 3481: debug2_f("channel %d: callback done", c->self);
1.44 markus 3482: }
1.426 djm 3483: c->lastused = monotime();
1.358 djm 3484: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3485: c->remote_window, c->remote_maxpacket);
1.339 markus 3486: return 0;
1.1 deraadt 3487: }
3488:
1.127 itojun 3489: static char *
1.114 markus 3490: reason2txt(int reason)
3491: {
1.143 deraadt 3492: switch (reason) {
1.114 markus 3493: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3494: return "administratively prohibited";
3495: case SSH2_OPEN_CONNECT_FAILED:
3496: return "connect failed";
3497: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3498: return "unknown channel type";
3499: case SSH2_OPEN_RESOURCE_SHORTAGE:
3500: return "resource shortage";
3501: }
1.117 stevesk 3502: return "unknown reason";
1.114 markus 3503: }
3504:
1.339 markus 3505: int
1.363 markus 3506: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3507: {
1.367 djm 3508: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3509: u_int32_t reason;
3510: char *msg = NULL;
3511: int r;
1.25 markus 3512:
1.363 markus 3513: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3514: return 0;
3515: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3516: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3517: "non-opening channel %d.", c->self);
3518: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
1.403 djm 3519: error_fr(r, "parse reason");
1.389 djm 3520: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3521: }
1.378 djm 3522: /* skip language */
3523: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3524: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3525: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3526: error_fr(r, "parse msg/lang");
1.389 djm 3527: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3528: }
1.367 djm 3529: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3530: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3531: free(msg);
3532: if (c->open_confirm) {
1.403 djm 3533: debug2_f("channel %d: callback start", c->self);
1.367 djm 3534: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
1.403 djm 3535: debug2_f("channel %d: callback done", c->self);
1.44 markus 3536: }
1.291 djm 3537: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3538: chan_mark_dead(ssh, c);
1.339 markus 3539: return 0;
1.44 markus 3540: }
3541:
1.339 markus 3542: int
1.363 markus 3543: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3544: {
1.367 djm 3545: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3546: Channel *c;
1.367 djm 3547: u_int32_t adjust;
3548: u_int new_rwin;
3549: int r;
1.1 deraadt 3550:
1.367 djm 3551: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3552: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3553: return 0;
1.372 markus 3554: }
1.367 djm 3555:
1.363 markus 3556: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3557: return 0;
1.389 djm 3558: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3559: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3560: error_fr(r, "parse adjust");
1.389 djm 3561: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3562: }
3563: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3564: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3565: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3566: c->self, adjust, c->remote_window);
3567: }
3568: c->remote_window = new_rwin;
1.339 markus 3569: return 0;
1.121 markus 3570: }
1.1 deraadt 3571:
1.339 markus 3572: int
1.363 markus 3573: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3574: {
1.367 djm 3575: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3576: Channel *c;
3577: struct channel_confirm *cc;
3578:
3579: /* Reset keepalive timeout */
1.389 djm 3580: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3581:
1.403 djm 3582: debug2_f("type %d id %d", type, id);
1.275 djm 3583:
1.367 djm 3584: if ((c = channel_lookup(ssh, id)) == NULL) {
1.403 djm 3585: logit_f("%d: unknown", id);
1.339 markus 3586: return 0;
1.367 djm 3587: }
1.363 markus 3588: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3589: return 0;
1.394 dtucker 3590: if (sshpkt_get_end(ssh) != 0)
1.389 djm 3591: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3592: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3593: return 0;
1.367 djm 3594: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3595: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 3596: freezero(cc, sizeof(*cc));
1.339 markus 3597: return 0;
1.275 djm 3598: }
1.121 markus 3599:
3600: /* -- tcp forwarding */
1.135 markus 3601:
3602: void
1.367 djm 3603: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3604: {
1.367 djm 3605: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3606: }
1.121 markus 3607:
1.312 djm 3608:
3609: /*
3610: * Determine whether or not a port forward listens to loopback, the
3611: * specified address or wildcard. On the client, a specified bind
3612: * address will always override gateway_ports. On the server, a
3613: * gateway_ports of 1 (``yes'') will override the client's specification
3614: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3615: * will bind to whatever address the client asked for.
3616: *
3617: * Special-case listen_addrs are:
3618: *
3619: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3620: * "" (empty string), "*" -> wildcard v4/v6
3621: * "localhost" -> loopback v4/v6
1.334 djm 3622: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3623: */
3624: static const char *
1.389 djm 3625: channel_fwd_bind_addr(struct ssh *ssh, const char *listen_addr, int *wildcardp,
1.336 millert 3626: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3627: {
3628: const char *addr = NULL;
3629: int wildcard = 0;
3630:
3631: if (listen_addr == NULL) {
3632: /* No address specified: default to gateway_ports setting */
1.336 millert 3633: if (fwd_opts->gateway_ports)
1.312 djm 3634: wildcard = 1;
1.336 millert 3635: } else if (fwd_opts->gateway_ports || is_client) {
1.404 djm 3636: if (((ssh->compat & SSH_OLD_FORWARD_ADDR) &&
1.312 djm 3637: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3638: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3639: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3640: wildcard = 1;
1.326 djm 3641: /*
3642: * Notify client if they requested a specific listen
3643: * address and it was overridden.
3644: */
3645: if (*listen_addr != '\0' &&
3646: strcmp(listen_addr, "0.0.0.0") != 0 &&
3647: strcmp(listen_addr, "*") != 0) {
1.389 djm 3648: ssh_packet_send_debug(ssh,
3649: "Forwarding listen address "
1.326 djm 3650: "\"%s\" overridden by server "
3651: "GatewayPorts", listen_addr);
3652: }
1.334 djm 3653: } else if (strcmp(listen_addr, "localhost") != 0 ||
3654: strcmp(listen_addr, "127.0.0.1") == 0 ||
3655: strcmp(listen_addr, "::1") == 0) {
1.395 djm 3656: /*
3657: * Accept explicit localhost address when
3658: * GatewayPorts=yes. The "localhost" hostname is
3659: * deliberately skipped here so it will listen on all
3660: * available local address families.
3661: */
1.334 djm 3662: addr = listen_addr;
1.326 djm 3663: }
1.334 djm 3664: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3665: strcmp(listen_addr, "::1") == 0) {
3666: /*
3667: * If a specific IPv4/IPv6 localhost address has been
3668: * requested then accept it even if gateway_ports is in
3669: * effect. This allows the client to prefer IPv4 or IPv6.
3670: */
3671: addr = listen_addr;
1.312 djm 3672: }
3673: if (wildcardp != NULL)
3674: *wildcardp = wildcard;
3675: return addr;
3676: }
3677:
1.160 markus 3678: static int
1.367 djm 3679: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3680: struct Forward *fwd, int *allocated_listen_port,
3681: struct ForwardOptions *fwd_opts)
1.25 markus 3682: {
1.113 markus 3683: Channel *c;
1.226 djm 3684: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3685: struct addrinfo hints, *ai, *aitop;
1.212 djm 3686: const char *host, *addr;
1.35 markus 3687: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3688: in_port_t *lport_p;
1.25 markus 3689:
1.212 djm 3690: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3691:
1.344 millert 3692: if (is_client && fwd->connect_path != NULL) {
3693: host = fwd->connect_path;
3694: } else {
3695: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3696: fwd->listen_host : fwd->connect_host;
3697: if (host == NULL) {
3698: error("No forward host name.");
3699: return 0;
3700: }
3701: if (strlen(host) >= NI_MAXHOST) {
3702: error("Forward host name too long.");
3703: return 0;
3704: }
1.87 markus 3705: }
1.25 markus 3706:
1.312 djm 3707: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3708: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3709: is_client, fwd_opts);
1.403 djm 3710: debug3_f("type %d wildcard %d addr %s", type, wildcard,
3711: (addr == NULL) ? "NULL" : addr);
1.212 djm 3712:
3713: /*
1.35 markus 3714: * getaddrinfo returns a loopback address if the hostname is
3715: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3716: */
1.35 markus 3717: memset(&hints, 0, sizeof(hints));
1.367 djm 3718: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3719: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3720: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3721: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3722: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3723: if (addr == NULL) {
3724: /* This really shouldn't happen */
1.389 djm 3725: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3726: ssh_gai_strerror(r));
1.212 djm 3727: } else {
1.403 djm 3728: error_f("getaddrinfo(%.64s): %s", addr,
1.271 dtucker 3729: ssh_gai_strerror(r));
1.212 djm 3730: }
1.218 markus 3731: return 0;
1.212 djm 3732: }
1.295 djm 3733: if (allocated_listen_port != NULL)
3734: *allocated_listen_port = 0;
1.35 markus 3735: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3736: switch (ai->ai_family) {
3737: case AF_INET:
3738: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3739: sin_port;
3740: break;
3741: case AF_INET6:
3742: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3743: sin6_port;
3744: break;
3745: default:
1.35 markus 3746: continue;
1.295 djm 3747: }
3748: /*
3749: * If allocating a port for -R forwards, then use the
3750: * same port for all address families.
3751: */
1.367 djm 3752: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3753: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3754: *allocated_listen_port > 0)
1.295 djm 3755: *lport_p = htons(*allocated_listen_port);
3756:
1.35 markus 3757: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3758: strport, sizeof(strport),
3759: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.403 djm 3760: error_f("getnameinfo failed");
1.35 markus 3761: continue;
3762: }
3763: /* Create a port to listen for the host. */
1.300 dtucker 3764: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 3765: if (sock == -1) {
1.35 markus 3766: /* this is no error since kernel may not support ipv6 */
1.377 djm 3767: verbose("socket [%s]:%s: %.100s", ntop, strport,
3768: strerror(errno));
1.35 markus 3769: continue;
3770: }
1.226 djm 3771:
1.376 djm 3772: set_reuseaddr(sock);
1.182 stevesk 3773:
1.295 djm 3774: debug("Local forwarding listening on %s port %s.",
3775: ntop, strport);
1.35 markus 3776:
3777: /* Bind the socket to the address. */
1.393 deraadt 3778: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3779: /*
3780: * address can be in if use ipv6 address is
3781: * already bound
3782: */
1.377 djm 3783: verbose("bind [%s]:%s: %.100s",
3784: ntop, strport, strerror(errno));
1.35 markus 3785: close(sock);
3786: continue;
3787: }
3788: /* Start listening for connections on the socket. */
1.393 deraadt 3789: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3790: error("listen [%s]:%s: %.100s", ntop, strport,
3791: strerror(errno));
1.35 markus 3792: close(sock);
3793: continue;
3794: }
1.295 djm 3795:
3796: /*
1.336 millert 3797: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3798: * record what we got.
3799: */
1.367 djm 3800: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3801: fwd->listen_port == 0 &&
1.295 djm 3802: allocated_listen_port != NULL &&
3803: *allocated_listen_port == 0) {
1.350 djm 3804: *allocated_listen_port = get_local_port(sock);
1.295 djm 3805: debug("Allocated listen port %d",
3806: *allocated_listen_port);
3807: }
3808:
1.35 markus 3809: /* Allocate a channel number for the socket. */
1.424 djm 3810: c = channel_new(ssh, "port-listener", type, sock, sock, -1,
1.51 markus 3811: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3812: 0, "port listener", 1);
1.293 djm 3813: c->path = xstrdup(host);
1.336 millert 3814: c->host_port = fwd->connect_port;
1.312 djm 3815: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3816: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.404 djm 3817: !(ssh->compat & SSH_BUG_DYNAMIC_RPORT))
1.315 markus 3818: c->listening_port = *allocated_listen_port;
3819: else
1.336 millert 3820: c->listening_port = fwd->listen_port;
1.35 markus 3821: success = 1;
3822: }
3823: if (success == 0)
1.403 djm 3824: error_f("cannot listen to port: %d", fwd->listen_port);
1.35 markus 3825: freeaddrinfo(aitop);
1.87 markus 3826: return success;
1.25 markus 3827: }
1.1 deraadt 3828:
1.336 millert 3829: static int
1.367 djm 3830: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3831: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3832: {
3833: struct sockaddr_un sunaddr;
3834: const char *path;
3835: Channel *c;
3836: int port, sock;
3837: mode_t omask;
3838:
3839: switch (type) {
3840: case SSH_CHANNEL_UNIX_LISTENER:
3841: if (fwd->connect_path != NULL) {
3842: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3843: error("Local connecting path too long: %s",
3844: fwd->connect_path);
3845: return 0;
3846: }
3847: path = fwd->connect_path;
3848: port = PORT_STREAMLOCAL;
3849: } else {
3850: if (fwd->connect_host == NULL) {
3851: error("No forward host name.");
3852: return 0;
3853: }
3854: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3855: error("Forward host name too long.");
3856: return 0;
3857: }
3858: path = fwd->connect_host;
3859: port = fwd->connect_port;
3860: }
3861: break;
3862: case SSH_CHANNEL_RUNIX_LISTENER:
3863: path = fwd->listen_path;
3864: port = PORT_STREAMLOCAL;
3865: break;
3866: default:
1.403 djm 3867: error_f("unexpected channel type %d", type);
1.336 millert 3868: return 0;
3869: }
3870:
3871: if (fwd->listen_path == NULL) {
3872: error("No forward path name.");
3873: return 0;
3874: }
3875: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3876: error("Local listening path too long: %s", fwd->listen_path);
3877: return 0;
3878: }
3879:
1.403 djm 3880: debug3_f("type %d path %s", type, fwd->listen_path);
1.336 millert 3881:
3882: /* Start a Unix domain listener. */
3883: omask = umask(fwd_opts->streamlocal_bind_mask);
3884: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3885: fwd_opts->streamlocal_bind_unlink);
3886: umask(omask);
3887: if (sock < 0)
3888: return 0;
3889:
3890: debug("Local forwarding listening on path %s.", fwd->listen_path);
3891:
3892: /* Allocate a channel number for the socket. */
1.424 djm 3893: c = channel_new(ssh, "unix-listener", type, sock, sock, -1,
1.336 millert 3894: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3895: 0, "unix listener", 1);
3896: c->path = xstrdup(path);
3897: c->host_port = port;
3898: c->listening_port = PORT_STREAMLOCAL;
3899: c->listening_addr = xstrdup(fwd->listen_path);
3900: return 1;
3901: }
3902:
3903: static int
1.367 djm 3904: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3905: const char *host, u_short port)
1.202 djm 3906: {
1.209 avsm 3907: u_int i;
3908: int found = 0;
1.202 djm 3909:
1.367 djm 3910: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3911: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3912: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3913: continue;
3914: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
1.403 djm 3915: debug2_f("close channel %d", i);
1.367 djm 3916: channel_free(ssh, c);
1.312 djm 3917: found = 1;
3918: }
3919: }
3920:
1.367 djm 3921: return found;
1.312 djm 3922: }
3923:
1.336 millert 3924: static int
1.367 djm 3925: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3926: {
3927: u_int i;
3928: int found = 0;
3929:
1.367 djm 3930: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3931: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3932: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3933: continue;
3934: if (c->path == NULL)
3935: continue;
3936: if (strcmp(c->path, path) == 0) {
1.403 djm 3937: debug2_f("close channel %d", i);
1.367 djm 3938: channel_free(ssh, c);
1.336 millert 3939: found = 1;
3940: }
3941: }
3942:
1.367 djm 3943: return found;
1.336 millert 3944: }
3945:
1.312 djm 3946: int
1.367 djm 3947: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3948: {
1.367 djm 3949: if (fwd->listen_path != NULL) {
3950: return channel_cancel_rport_listener_streamlocal(ssh,
3951: fwd->listen_path);
3952: } else {
3953: return channel_cancel_rport_listener_tcpip(ssh,
3954: fwd->listen_host, fwd->listen_port);
3955: }
1.336 millert 3956: }
3957:
3958: static int
1.367 djm 3959: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3960: const char *lhost, u_short lport, int cport,
3961: struct ForwardOptions *fwd_opts)
1.312 djm 3962: {
3963: u_int i;
3964: int found = 0;
1.389 djm 3965: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 3966:
1.367 djm 3967: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3968: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3969: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3970: continue;
1.313 markus 3971: if (c->listening_port != lport)
1.312 djm 3972: continue;
1.313 markus 3973: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3974: /* skip dynamic forwardings */
3975: if (c->host_port == 0)
3976: continue;
3977: } else {
3978: if (c->host_port != cport)
3979: continue;
3980: }
1.312 djm 3981: if ((c->listening_addr == NULL && addr != NULL) ||
3982: (c->listening_addr != NULL && addr == NULL))
3983: continue;
3984: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.403 djm 3985: debug2_f("close channel %d", i);
1.367 djm 3986: channel_free(ssh, c);
1.202 djm 3987: found = 1;
3988: }
3989: }
3990:
1.367 djm 3991: return found;
1.202 djm 3992: }
3993:
1.336 millert 3994: static int
1.367 djm 3995: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3996: {
3997: u_int i;
3998: int found = 0;
3999:
4000: if (path == NULL) {
1.403 djm 4001: error_f("no path specified.");
1.336 millert 4002: return 0;
4003: }
4004:
1.367 djm 4005: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
4006: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 4007: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
4008: continue;
4009: if (c->listening_addr == NULL)
4010: continue;
4011: if (strcmp(c->listening_addr, path) == 0) {
1.403 djm 4012: debug2_f("close channel %d", i);
1.367 djm 4013: channel_free(ssh, c);
1.336 millert 4014: found = 1;
4015: }
4016: }
4017:
1.367 djm 4018: return found;
1.336 millert 4019: }
4020:
4021: int
1.367 djm 4022: channel_cancel_lport_listener(struct ssh *ssh,
4023: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 4024: {
1.367 djm 4025: if (fwd->listen_path != NULL) {
4026: return channel_cancel_lport_listener_streamlocal(ssh,
4027: fwd->listen_path);
4028: } else {
4029: return channel_cancel_lport_listener_tcpip(ssh,
4030: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
4031: }
1.336 millert 4032: }
4033:
1.362 markus 4034: /* protocol local port fwd, used by ssh */
1.160 markus 4035: int
1.367 djm 4036: channel_setup_local_fwd_listener(struct ssh *ssh,
4037: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 4038: {
1.336 millert 4039: if (fwd->listen_path != NULL) {
1.367 djm 4040: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 4041: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
4042: } else {
1.367 djm 4043: return channel_setup_fwd_listener_tcpip(ssh,
4044: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 4045: }
1.160 markus 4046: }
4047:
1.381 djm 4048: /* Matches a remote forwarding permission against a requested forwarding */
4049: static int
4050: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
4051: {
4052: int ret;
4053: char *lhost;
4054:
4055: /* XXX add ACLs for streamlocal */
4056: if (fwd->listen_path != NULL)
4057: return 1;
4058:
4059: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
4060: return 0;
4061:
4062: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
4063: allowed_open->listen_port != fwd->listen_port)
4064: return 0;
4065:
4066: /* Match hostnames case-insensitively */
4067: lhost = xstrdup(fwd->listen_host);
4068: lowercase(lhost);
4069: ret = match_pattern(lhost, allowed_open->listen_host);
4070: free(lhost);
4071:
4072: return ret;
4073: }
4074:
4075: /* Checks whether a requested remote forwarding is permitted */
4076: static int
4077: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
4078: {
4079: struct ssh_channels *sc = ssh->chanctxt;
4080: struct permission_set *pset = &sc->remote_perms;
4081: u_int i, permit, permit_adm = 1;
4082: struct permission *perm;
4083:
4084: /* XXX apply GatewayPorts override before checking? */
4085:
4086: permit = pset->all_permitted;
4087: if (!permit) {
4088: for (i = 0; i < pset->num_permitted_user; i++) {
4089: perm = &pset->permitted_user[i];
4090: if (remote_open_match(perm, fwd)) {
4091: permit = 1;
4092: break;
4093: }
4094: }
4095: }
4096:
4097: if (pset->num_permitted_admin > 0) {
4098: permit_adm = 0;
4099: for (i = 0; i < pset->num_permitted_admin; i++) {
4100: perm = &pset->permitted_admin[i];
4101: if (remote_open_match(perm, fwd)) {
4102: permit_adm = 1;
4103: break;
4104: }
4105: }
4106: }
4107:
4108: return permit && permit_adm;
4109: }
4110:
1.160 markus 4111: /* protocol v2 remote port fwd, used by sshd */
4112: int
1.367 djm 4113: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 4114: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 4115: {
1.381 djm 4116: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 4117: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 4118: if (fwd->listen_path != NULL)
4119: /* XXX always allowed, see remote_open_match() */
4120: logit("Received request from %.100s port %d to "
4121: "remote forward to path \"%.100s\", "
4122: "but the request was denied.",
4123: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
4124: fwd->listen_path);
4125: else if(fwd->listen_host != NULL)
4126: logit("Received request from %.100s port %d to "
4127: "remote forward to host %.100s port %d, "
4128: "but the request was denied.",
4129: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
4130: fwd->listen_host, fwd->listen_port );
4131: else
4132: logit("Received request from %.100s port %d to remote "
4133: "forward, but the request was denied.",
4134: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 4135: return 0;
4136: }
1.336 millert 4137: if (fwd->listen_path != NULL) {
1.367 djm 4138: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 4139: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
4140: } else {
1.367 djm 4141: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 4142: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
4143: fwd_opts);
4144: }
1.160 markus 4145: }
4146:
1.27 markus 4147: /*
1.312 djm 4148: * Translate the requested rfwd listen host to something usable for
4149: * this server.
4150: */
4151: static const char *
4152: channel_rfwd_bind_host(const char *listen_host)
4153: {
4154: if (listen_host == NULL) {
1.378 djm 4155: return "localhost";
1.312 djm 4156: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 4157: return "";
1.312 djm 4158: } else
4159: return listen_host;
4160: }
4161:
4162: /*
1.27 markus 4163: * Initiate forwarding of connections to port "port" on remote host through
4164: * the secure channel to host:port from local side.
1.315 markus 4165: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 4166: * channel_update_permission().
1.27 markus 4167: */
1.253 markus 4168: int
1.367 djm 4169: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 4170: {
1.367 djm 4171: int r, success = 0, idx = -1;
1.421 mbuhl 4172: const char *host_to_connect, *listen_host, *listen_path;
1.367 djm 4173: int port_to_connect, listen_port;
1.73 markus 4174:
1.25 markus 4175: /* Send the forward request to the remote side. */
1.358 djm 4176: if (fwd->listen_path != NULL) {
1.367 djm 4177: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4178: (r = sshpkt_put_cstring(ssh,
4179: "streamlocal-forward@openssh.com")) != 0 ||
4180: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4181: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
4182: (r = sshpkt_send(ssh)) != 0 ||
4183: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4184: fatal_fr(r, "request streamlocal");
1.336 millert 4185: } else {
1.367 djm 4186: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4187: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
4188: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4189: (r = sshpkt_put_cstring(ssh,
4190: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
4191: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
4192: (r = sshpkt_send(ssh)) != 0 ||
4193: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4194: fatal_fr(r, "request tcpip-forward");
1.73 markus 4195: }
1.358 djm 4196: /* Assume that server accepts the request */
4197: success = 1;
1.73 markus 4198: if (success) {
1.305 djm 4199: /* Record that connection to this host/port is permitted. */
1.367 djm 4200: host_to_connect = listen_host = listen_path = NULL;
4201: port_to_connect = listen_port = 0;
1.336 millert 4202: if (fwd->connect_path != NULL) {
1.421 mbuhl 4203: host_to_connect = fwd->connect_path;
1.367 djm 4204: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 4205: } else {
1.421 mbuhl 4206: host_to_connect = fwd->connect_host;
1.367 djm 4207: port_to_connect = fwd->connect_port;
1.336 millert 4208: }
4209: if (fwd->listen_path != NULL) {
1.421 mbuhl 4210: listen_path = fwd->listen_path;
1.367 djm 4211: listen_port = PORT_STREAMLOCAL;
1.336 millert 4212: } else {
1.421 mbuhl 4213: listen_host = fwd->listen_host;
1.367 djm 4214: listen_port = fwd->listen_port;
4215: }
1.381 djm 4216: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 4217: host_to_connect, port_to_connect,
4218: listen_host, listen_path, listen_port, NULL);
1.44 markus 4219: }
1.367 djm 4220: return idx;
1.1 deraadt 4221: }
4222:
1.333 markus 4223: static int
1.381 djm 4224: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 4225: int requestedport)
1.333 markus 4226: {
4227: if (allowed_open->host_to_connect == NULL)
4228: return 0;
4229: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
4230: allowed_open->port_to_connect != requestedport)
4231: return 0;
1.351 dtucker 4232: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
4233: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 4234: return 0;
4235: return 1;
4236: }
4237:
4238: /*
1.336 millert 4239: * Note that in the listen host/port case
1.333 markus 4240: * we don't support FWD_PERMIT_ANY_PORT and
4241: * need to translate between the configured-host (listen_host)
4242: * and what we've sent to the remote server (channel_rfwd_bind_host)
4243: */
4244: static int
1.381 djm 4245: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 4246: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 4247: {
4248: const char *allowed_host;
4249:
4250: if (allowed_open->host_to_connect == NULL)
4251: return 0;
4252: if (allowed_open->listen_port != requestedport)
4253: return 0;
1.335 djm 4254: if (!translate && allowed_open->listen_host == NULL &&
4255: requestedhost == NULL)
4256: return 1;
1.333 markus 4257: allowed_host = translate ?
4258: channel_rfwd_bind_host(allowed_open->listen_host) :
4259: allowed_open->listen_host;
1.382 djm 4260: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 4261: strcmp(allowed_host, requestedhost) != 0)
4262: return 0;
4263: return 1;
4264: }
4265:
1.336 millert 4266: static int
1.381 djm 4267: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 4268: const char *requestedpath)
4269: {
4270: if (allowed_open->host_to_connect == NULL)
4271: return 0;
4272: if (allowed_open->listen_port != PORT_STREAMLOCAL)
4273: return 0;
4274: if (allowed_open->listen_path == NULL ||
4275: strcmp(allowed_open->listen_path, requestedpath) != 0)
4276: return 0;
4277: return 1;
4278: }
4279:
1.27 markus 4280: /*
1.208 deraadt 4281: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 4282: * local side.
4283: */
1.336 millert 4284: static int
1.367 djm 4285: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
4286: const char *host, u_short port)
1.202 djm 4287: {
1.367 djm 4288: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4289: struct permission_set *pset = &sc->local_perms;
1.367 djm 4290: int r;
4291: u_int i;
1.397 markus 4292: struct permission *perm = NULL;
1.202 djm 4293:
1.381 djm 4294: for (i = 0; i < pset->num_permitted_user; i++) {
4295: perm = &pset->permitted_user[i];
4296: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 4297: break;
1.381 djm 4298: perm = NULL;
1.202 djm 4299: }
1.381 djm 4300: if (perm == NULL) {
1.403 djm 4301: debug_f("requested forward not found");
1.312 djm 4302: return -1;
1.202 djm 4303: }
1.367 djm 4304: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4305: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
4306: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4307: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
4308: (r = sshpkt_put_u32(ssh, port)) != 0 ||
4309: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4310: fatal_fr(r, "send cancel");
1.367 djm 4311:
1.381 djm 4312: fwd_perm_clear(perm); /* unregister */
1.336 millert 4313:
4314: return 0;
4315: }
4316:
4317: /*
4318: * Request cancellation of remote forwarding of Unix domain socket
4319: * path from local side.
4320: */
4321: static int
1.367 djm 4322: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 4323: {
1.367 djm 4324: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4325: struct permission_set *pset = &sc->local_perms;
1.367 djm 4326: int r;
4327: u_int i;
1.397 markus 4328: struct permission *perm = NULL;
1.336 millert 4329:
1.381 djm 4330: for (i = 0; i < pset->num_permitted_user; i++) {
4331: perm = &pset->permitted_user[i];
4332: if (open_listen_match_streamlocal(perm, path))
1.336 millert 4333: break;
1.381 djm 4334: perm = NULL;
1.336 millert 4335: }
1.381 djm 4336: if (perm == NULL) {
1.403 djm 4337: debug_f("requested forward not found");
1.336 millert 4338: return -1;
4339: }
1.367 djm 4340: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4341: (r = sshpkt_put_cstring(ssh,
4342: "cancel-streamlocal-forward@openssh.com")) != 0 ||
4343: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4344: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
4345: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4346: fatal_fr(r, "send cancel");
1.367 djm 4347:
1.381 djm 4348: fwd_perm_clear(perm); /* unregister */
1.312 djm 4349:
4350: return 0;
1.202 djm 4351: }
4352:
4353: /*
1.336 millert 4354: * Request cancellation of remote forwarding of a connection from local side.
4355: */
4356: int
1.367 djm 4357: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 4358: {
4359: if (fwd->listen_path != NULL) {
1.367 djm 4360: return channel_request_rforward_cancel_streamlocal(ssh,
4361: fwd->listen_path);
1.336 millert 4362: } else {
1.367 djm 4363: return channel_request_rforward_cancel_tcpip(ssh,
4364: fwd->listen_host,
4365: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 4366: }
1.1 deraadt 4367: }
4368:
1.99 markus 4369: /*
1.381 djm 4370: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 4371: * usually called by the server, because the user could connect to any port
4372: * anyway, and the server has no way to know but to trust the client anyway.
4373: */
4374: void
1.381 djm 4375: channel_permit_all(struct ssh *ssh, int where)
4376: {
4377: struct permission_set *pset = permission_set_get(ssh, where);
4378:
4379: if (pset->num_permitted_user == 0)
4380: pset->all_permitted = 1;
4381: }
4382:
4383: /*
4384: * Permit the specified host/port for forwarding.
4385: */
4386: void
4387: channel_add_permission(struct ssh *ssh, int who, int where,
4388: char *host, int port)
4389: {
4390: int local = where == FORWARD_LOCAL;
4391: struct permission_set *pset = permission_set_get(ssh, where);
4392:
4393: debug("allow %s forwarding to host %s port %d",
4394: fwd_ident(who, where), host, port);
4395: /*
4396: * Remote forwards set listen_host/port, local forwards set
4397: * host/port_to_connect.
4398: */
4399: permission_set_add(ssh, who, where,
4400: local ? host : 0, local ? port : 0,
4401: local ? NULL : host, NULL, local ? 0 : port, NULL);
4402: pset->all_permitted = 0;
4403: }
4404:
4405: /*
4406: * Administratively disable forwarding.
4407: */
4408: void
4409: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4410: {
1.381 djm 4411: channel_clear_permission(ssh, FORWARD_ADM, where);
4412: permission_set_add(ssh, FORWARD_ADM, where,
4413: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4414: }
4415:
1.381 djm 4416: /*
4417: * Clear a list of permitted opens.
4418: */
1.101 markus 4419: void
1.381 djm 4420: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4421: {
1.381 djm 4422: struct permission **permp;
4423: u_int *npermp;
1.367 djm 4424:
1.381 djm 4425: permission_set_get_array(ssh, who, where, &permp, &npermp);
4426: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4427: *npermp = 0;
1.315 markus 4428: }
4429:
4430: /*
4431: * Update the listen port for a dynamic remote forward, after
4432: * the actual 'newport' has been allocated. If 'newport' < 0 is
4433: * passed then they entry will be invalidated.
4434: */
4435: void
1.381 djm 4436: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4437: {
1.381 djm 4438: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4439:
1.381 djm 4440: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
1.403 djm 4441: debug_f("index out of range: %d num_permitted_user %d",
4442: idx, pset->num_permitted_user);
1.315 markus 4443: return;
4444: }
4445: debug("%s allowed port %d for forwarding to host %s port %d",
4446: newport > 0 ? "Updating" : "Removing",
4447: newport,
1.381 djm 4448: pset->permitted_user[idx].host_to_connect,
4449: pset->permitted_user[idx].port_to_connect);
1.367 djm 4450: if (newport <= 0)
1.381 djm 4451: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4452: else {
1.381 djm 4453: pset->permitted_user[idx].listen_port =
1.404 djm 4454: (ssh->compat & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
1.315 markus 4455: }
1.99 markus 4456: }
4457:
1.314 dtucker 4458: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4459: int
4460: permitopen_port(const char *p)
4461: {
4462: int port;
4463:
4464: if (strcmp(p, "*") == 0)
4465: return FWD_PERMIT_ANY_PORT;
4466: if ((port = a2port(p)) > 0)
4467: return port;
4468: return -1;
4469: }
4470:
1.276 djm 4471: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4472: static int
1.276 djm 4473: connect_next(struct channel_connect *cctx)
1.41 markus 4474: {
1.276 djm 4475: int sock, saved_errno;
1.336 millert 4476: struct sockaddr_un *sunaddr;
1.367 djm 4477: char ntop[NI_MAXHOST];
4478: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4479:
1.276 djm 4480: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4481: switch (cctx->ai->ai_family) {
4482: case AF_UNIX:
4483: /* unix:pathname instead of host:port */
4484: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4485: strlcpy(ntop, "unix", sizeof(ntop));
4486: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4487: break;
4488: case AF_INET:
4489: case AF_INET6:
4490: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4491: ntop, sizeof(ntop), strport, sizeof(strport),
4492: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.420 djm 4493: error_f("getnameinfo failed");
1.336 millert 4494: continue;
4495: }
4496: break;
4497: default:
1.41 markus 4498: continue;
4499: }
1.420 djm 4500: debug_f("start for host %.100s ([%.100s]:%s)",
4501: cctx->host, ntop, strport);
1.300 dtucker 4502: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4503: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4504: if (cctx->ai->ai_next == NULL)
1.186 djm 4505: error("socket: %.100s", strerror(errno));
4506: else
4507: verbose("socket: %.100s", strerror(errno));
1.41 markus 4508: continue;
4509: }
1.205 djm 4510: if (set_nonblock(sock) == -1)
1.403 djm 4511: fatal_f("set_nonblock(%d)", sock);
1.276 djm 4512: if (connect(sock, cctx->ai->ai_addr,
4513: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
1.420 djm 4514: debug_f("host %.100s ([%.100s]:%s): %.100s",
4515: cctx->host, ntop, strport, strerror(errno));
1.276 djm 4516: saved_errno = errno;
1.41 markus 4517: close(sock);
1.276 djm 4518: errno = saved_errno;
1.89 stevesk 4519: continue; /* fail -- try next */
1.41 markus 4520: }
1.336 millert 4521: if (cctx->ai->ai_family != AF_UNIX)
4522: set_nodelay(sock);
1.420 djm 4523: debug_f("connect host %.100s ([%.100s]:%s) in progress, fd=%d",
4524: cctx->host, ntop, strport, sock);
1.276 djm 4525: cctx->ai = cctx->ai->ai_next;
4526: return sock;
4527: }
4528: return -1;
4529: }
1.41 markus 4530:
1.276 djm 4531: static void
4532: channel_connect_ctx_free(struct channel_connect *cctx)
4533: {
1.321 djm 4534: free(cctx->host);
1.336 millert 4535: if (cctx->aitop) {
4536: if (cctx->aitop->ai_family == AF_UNIX)
4537: free(cctx->aitop);
4538: else
4539: freeaddrinfo(cctx->aitop);
4540: }
1.329 tedu 4541: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4542: }
4543:
1.357 dtucker 4544: /*
1.372 markus 4545: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4546: * passing back the failure reason if appropriate.
4547: */
1.372 markus 4548: static int
4549: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4550: char *ctype, char *rname, struct channel_connect *cctx,
4551: int *reason, const char **errmsg)
1.276 djm 4552: {
4553: struct addrinfo hints;
4554: int gaierr;
4555: int sock = -1;
4556: char strport[NI_MAXSERV];
1.336 millert 4557:
4558: if (port == PORT_STREAMLOCAL) {
4559: struct sockaddr_un *sunaddr;
4560: struct addrinfo *ai;
4561:
4562: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4563: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4564: return -1;
1.336 millert 4565: }
4566:
4567: /*
4568: * Fake up a struct addrinfo for AF_UNIX connections.
4569: * channel_connect_ctx_free() must check ai_family
4570: * and use free() not freeaddirinfo() for AF_UNIX.
4571: */
4572: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4573: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4574: ai->ai_addr = (struct sockaddr *)(ai + 1);
4575: ai->ai_addrlen = sizeof(*sunaddr);
4576: ai->ai_family = AF_UNIX;
1.372 markus 4577: ai->ai_socktype = socktype;
1.336 millert 4578: ai->ai_protocol = PF_UNSPEC;
4579: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4580: sunaddr->sun_family = AF_UNIX;
4581: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4582: cctx->aitop = ai;
1.336 millert 4583: } else {
4584: memset(&hints, 0, sizeof(hints));
1.367 djm 4585: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4586: hints.ai_socktype = socktype;
1.336 millert 4587: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4588: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4589: != 0) {
4590: if (errmsg != NULL)
4591: *errmsg = ssh_gai_strerror(gaierr);
4592: if (reason != NULL)
4593: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4594: error("connect_to %.100s: unknown host (%s)", name,
4595: ssh_gai_strerror(gaierr));
1.372 markus 4596: return -1;
1.336 millert 4597: }
1.41 markus 4598: }
1.276 djm 4599:
1.372 markus 4600: cctx->host = xstrdup(name);
4601: cctx->port = port;
4602: cctx->ai = cctx->aitop;
1.276 djm 4603:
1.372 markus 4604: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4605: error("connect to %.100s port %d failed: %s",
1.336 millert 4606: name, port, strerror(errno));
1.372 markus 4607: return -1;
4608: }
4609:
4610: return sock;
4611: }
4612:
4613: /* Return CONNECTING channel to remote host:port or local socket path */
4614: static Channel *
4615: connect_to(struct ssh *ssh, const char *host, int port,
4616: char *ctype, char *rname)
4617: {
4618: struct channel_connect cctx;
4619: Channel *c;
4620: int sock;
4621:
4622: memset(&cctx, 0, sizeof(cctx));
4623: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4624: &cctx, NULL, NULL);
4625: if (sock == -1) {
1.276 djm 4626: channel_connect_ctx_free(&cctx);
4627: return NULL;
1.41 markus 4628: }
1.367 djm 4629: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4630: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4631: c->host_port = port;
4632: c->path = xstrdup(host);
1.276 djm 4633: c->connect_ctx = cctx;
1.372 markus 4634:
1.276 djm 4635: return c;
1.41 markus 4636: }
1.99 markus 4637:
1.354 markus 4638: /*
4639: * returns either the newly connected channel or the downstream channel
4640: * that needs to deal with this connection.
4641: */
1.276 djm 4642: Channel *
1.367 djm 4643: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4644: u_short listen_port, char *ctype, char *rname)
1.73 markus 4645: {
1.367 djm 4646: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4647: struct permission_set *pset = &sc->local_perms;
1.367 djm 4648: u_int i;
1.381 djm 4649: struct permission *perm;
1.99 markus 4650:
1.381 djm 4651: for (i = 0; i < pset->num_permitted_user; i++) {
4652: perm = &pset->permitted_user[i];
4653: if (open_listen_match_tcpip(perm,
4654: listen_host, listen_port, 1)) {
4655: if (perm->downstream)
4656: return perm->downstream;
4657: if (perm->port_to_connect == 0)
1.372 markus 4658: return rdynamic_connect_prepare(ssh,
4659: ctype, rname);
1.367 djm 4660: return connect_to(ssh,
1.381 djm 4661: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4662: ctype, rname);
1.276 djm 4663: }
4664: }
1.74 markus 4665: error("WARNING: Server requests forwarding for unknown listen_port %d",
4666: listen_port);
1.276 djm 4667: return NULL;
1.73 markus 4668: }
4669:
1.336 millert 4670: Channel *
1.367 djm 4671: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4672: char *ctype, char *rname)
1.336 millert 4673: {
1.367 djm 4674: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4675: struct permission_set *pset = &sc->local_perms;
1.367 djm 4676: u_int i;
1.381 djm 4677: struct permission *perm;
1.336 millert 4678:
1.381 djm 4679: for (i = 0; i < pset->num_permitted_user; i++) {
4680: perm = &pset->permitted_user[i];
4681: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4682: return connect_to(ssh,
1.381 djm 4683: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4684: ctype, rname);
1.336 millert 4685: }
4686: }
4687: error("WARNING: Server requests forwarding for unknown path %.100s",
4688: path);
4689: return NULL;
4690: }
4691:
1.99 markus 4692: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4693: Channel *
1.367 djm 4694: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4695: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4696: {
1.367 djm 4697: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4698: struct permission_set *pset = &sc->local_perms;
1.372 markus 4699: struct channel_connect cctx;
4700: Channel *c;
1.367 djm 4701: u_int i, permit, permit_adm = 1;
1.372 markus 4702: int sock;
1.381 djm 4703: struct permission *perm;
1.99 markus 4704:
1.381 djm 4705: permit = pset->all_permitted;
1.99 markus 4706: if (!permit) {
1.381 djm 4707: for (i = 0; i < pset->num_permitted_user; i++) {
4708: perm = &pset->permitted_user[i];
4709: if (open_match(perm, host, port)) {
1.99 markus 4710: permit = 1;
1.333 markus 4711: break;
4712: }
1.367 djm 4713: }
1.257 dtucker 4714: }
1.99 markus 4715:
1.381 djm 4716: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4717: permit_adm = 0;
1.381 djm 4718: for (i = 0; i < pset->num_permitted_admin; i++) {
4719: perm = &pset->permitted_admin[i];
4720: if (open_match(perm, host, port)) {
1.257 dtucker 4721: permit_adm = 1;
1.333 markus 4722: break;
4723: }
1.367 djm 4724: }
1.99 markus 4725: }
1.257 dtucker 4726:
4727: if (!permit || !permit_adm) {
1.391 florian 4728: logit("Received request from %.100s port %d to connect to "
4729: "host %.100s port %d, but the request was denied.",
4730: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4731: if (reason != NULL)
4732: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4733: return NULL;
1.99 markus 4734: }
1.372 markus 4735:
4736: memset(&cctx, 0, sizeof(cctx));
4737: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4738: &cctx, reason, errmsg);
4739: if (sock == -1) {
4740: channel_connect_ctx_free(&cctx);
4741: return NULL;
4742: }
4743:
4744: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4745: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4746: c->host_port = port;
4747: c->path = xstrdup(host);
4748: c->connect_ctx = cctx;
4749:
4750: return c;
1.336 millert 4751: }
4752:
4753: /* Check if connecting to that path is permitted and connect. */
4754: Channel *
1.367 djm 4755: channel_connect_to_path(struct ssh *ssh, const char *path,
4756: char *ctype, char *rname)
1.336 millert 4757: {
1.367 djm 4758: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4759: struct permission_set *pset = &sc->local_perms;
1.367 djm 4760: u_int i, permit, permit_adm = 1;
1.381 djm 4761: struct permission *perm;
1.336 millert 4762:
1.381 djm 4763: permit = pset->all_permitted;
1.336 millert 4764: if (!permit) {
1.381 djm 4765: for (i = 0; i < pset->num_permitted_user; i++) {
4766: perm = &pset->permitted_user[i];
4767: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4768: permit = 1;
4769: break;
4770: }
1.367 djm 4771: }
1.336 millert 4772: }
4773:
1.381 djm 4774: if (pset->num_permitted_admin > 0) {
1.336 millert 4775: permit_adm = 0;
1.381 djm 4776: for (i = 0; i < pset->num_permitted_admin; i++) {
4777: perm = &pset->permitted_admin[i];
4778: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4779: permit_adm = 1;
4780: break;
4781: }
1.367 djm 4782: }
1.336 millert 4783: }
4784:
4785: if (!permit || !permit_adm) {
4786: logit("Received request to connect to path %.100s, "
4787: "but the request was denied.", path);
4788: return NULL;
4789: }
1.367 djm 4790: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4791: }
4792:
4793: void
1.367 djm 4794: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4795: {
1.367 djm 4796: struct ssh_channels *sc = ssh->chanctxt;
4797: struct winsize ws;
4798: int r;
1.209 avsm 4799: u_int i;
1.204 djm 4800:
1.367 djm 4801: for (i = 0; i < sc->channels_alloc; i++) {
4802: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4803: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4804: continue;
1.393 deraadt 4805: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4806: continue;
1.367 djm 4807: channel_request_start(ssh, i, "window-change", 0);
4808: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4809: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4810: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4811: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4812: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4813: fatal_fr(r, "channel %u; send window-change", i);
1.204 djm 4814: }
1.372 markus 4815: }
4816:
4817: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4818: static Channel *
4819: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4820: {
4821: Channel *c;
4822: int r;
4823:
4824: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4825: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4826: c->host_port = 0;
4827: c->path = NULL;
4828:
4829: /*
4830: * We need to open the channel before we have a FD,
4831: * so that we can get SOCKS header from peer.
4832: */
4833: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4834: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4835: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4836: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 4837: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0)
4838: fatal_fr(r, "channel %i; confirm", c->self);
1.372 markus 4839: return c;
4840: }
4841:
4842: /* Return CONNECTING socket to remote host:port or local socket path */
4843: static int
4844: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4845: {
1.405 markus 4846: struct ssh_channels *sc = ssh->chanctxt;
4847: struct permission_set *pset = &sc->local_perms;
4848: struct permission *perm;
1.372 markus 4849: struct channel_connect cctx;
1.405 markus 4850: u_int i, permit_adm = 1;
1.372 markus 4851: int sock;
1.405 markus 4852:
4853: if (pset->num_permitted_admin > 0) {
4854: permit_adm = 0;
4855: for (i = 0; i < pset->num_permitted_admin; i++) {
4856: perm = &pset->permitted_admin[i];
4857: if (open_match(perm, c->path, c->host_port)) {
4858: permit_adm = 1;
4859: break;
4860: }
4861: }
4862: }
4863: if (!permit_adm) {
4864: debug_f("requested forward not permitted");
4865: return -1;
4866: }
1.372 markus 4867:
4868: memset(&cctx, 0, sizeof(cctx));
4869: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4870: NULL, &cctx, NULL, NULL);
4871: if (sock == -1)
4872: channel_connect_ctx_free(&cctx);
4873: else {
4874: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4875: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4876: c->connect_ctx = cctx;
4877: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4878: }
4879: return sock;
1.99 markus 4880: }
4881:
1.121 markus 4882: /* -- X11 forwarding */
1.1 deraadt 4883:
1.27 markus 4884: /*
4885: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4886: * Returns 0 and a suitable display number for the DISPLAY variable
4887: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4888: */
1.141 stevesk 4889: int
1.367 djm 4890: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4891: int x11_use_localhost, int single_connection,
4892: u_int *display_numberp, int **chanids)
1.1 deraadt 4893: {
1.149 markus 4894: Channel *nc = NULL;
1.31 markus 4895: int display_number, sock;
4896: u_short port;
1.35 markus 4897: struct addrinfo hints, *ai, *aitop;
4898: char strport[NI_MAXSERV];
4899: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4900:
1.224 markus 4901: if (chanids == NULL)
4902: return -1;
4903:
1.33 markus 4904: for (display_number = x11_display_offset;
1.148 deraadt 4905: display_number < MAX_DISPLAYS;
4906: display_number++) {
1.25 markus 4907: port = 6000 + display_number;
1.35 markus 4908: memset(&hints, 0, sizeof(hints));
1.367 djm 4909: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4910: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4911: hints.ai_socktype = SOCK_STREAM;
4912: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4913: if ((gaierr = getaddrinfo(NULL, strport,
4914: &hints, &aitop)) != 0) {
1.271 dtucker 4915: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4916: return -1;
1.25 markus 4917: }
1.35 markus 4918: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4919: if (ai->ai_family != AF_INET &&
4920: ai->ai_family != AF_INET6)
1.35 markus 4921: continue;
1.300 dtucker 4922: sock = socket(ai->ai_family, ai->ai_socktype,
4923: ai->ai_protocol);
1.393 deraadt 4924: if (sock == -1) {
1.35 markus 4925: error("socket: %.100s", strerror(errno));
1.203 markus 4926: freeaddrinfo(aitop);
1.141 stevesk 4927: return -1;
1.35 markus 4928: }
1.376 djm 4929: set_reuseaddr(sock);
1.393 deraadt 4930: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.403 djm 4931: debug2_f("bind port %d: %.100s", port,
4932: strerror(errno));
1.35 markus 4933: close(sock);
1.367 djm 4934: for (n = 0; n < num_socks; n++)
1.35 markus 4935: close(socks[n]);
4936: num_socks = 0;
4937: break;
4938: }
4939: socks[num_socks++] = sock;
4940: if (num_socks == NUM_SOCKS)
4941: break;
1.25 markus 4942: }
1.83 stevesk 4943: freeaddrinfo(aitop);
1.35 markus 4944: if (num_socks > 0)
4945: break;
1.25 markus 4946: }
4947: if (display_number >= MAX_DISPLAYS) {
4948: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4949: return -1;
1.25 markus 4950: }
4951: /* Start listening for connections on the socket. */
1.35 markus 4952: for (n = 0; n < num_socks; n++) {
4953: sock = socks[n];
1.393 deraadt 4954: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 4955: error("listen: %.100s", strerror(errno));
4956: close(sock);
1.141 stevesk 4957: return -1;
1.35 markus 4958: }
1.25 markus 4959: }
1.35 markus 4960:
4961: /* Allocate a channel for each socket. */
1.242 djm 4962: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4963: for (n = 0; n < num_socks; n++) {
4964: sock = socks[n];
1.424 djm 4965: nc = channel_new(ssh, "x11-listener",
1.51 markus 4966: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4967: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4968: 0, "X11 inet listener", 1);
1.167 markus 4969: nc->single_connection = single_connection;
1.224 markus 4970: (*chanids)[n] = nc->self;
1.35 markus 4971: }
1.224 markus 4972: (*chanids)[n] = -1;
1.1 deraadt 4973:
1.141 stevesk 4974: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4975: *display_numberp = display_number;
1.367 djm 4976: return 0;
1.1 deraadt 4977: }
4978:
1.127 itojun 4979: static int
1.77 markus 4980: connect_local_xsocket(u_int dnr)
1.1 deraadt 4981: {
1.25 markus 4982: int sock;
4983: struct sockaddr_un addr;
4984:
1.147 stevesk 4985: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 deraadt 4986: if (sock == -1)
1.147 stevesk 4987: error("socket: %.100s", strerror(errno));
4988: memset(&addr, 0, sizeof(addr));
4989: addr.sun_family = AF_UNIX;
4990: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4991: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4992: return sock;
4993: close(sock);
1.25 markus 4994: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4995: return -1;
1.1 deraadt 4996: }
4997:
1.51 markus 4998: int
1.367 djm 4999: x11_connect_display(struct ssh *ssh)
1.1 deraadt 5000: {
1.248 deraadt 5001: u_int display_number;
1.25 markus 5002: const char *display;
1.51 markus 5003: char buf[1024], *cp;
1.35 markus 5004: struct addrinfo hints, *ai, *aitop;
5005: char strport[NI_MAXSERV];
1.248 deraadt 5006: int gaierr, sock = 0;
1.25 markus 5007:
5008: /* Try to open a socket for the local X server. */
5009: display = getenv("DISPLAY");
5010: if (!display) {
5011: error("DISPLAY not set.");
1.51 markus 5012: return -1;
1.25 markus 5013: }
1.27 markus 5014: /*
5015: * Now we decode the value of the DISPLAY variable and make a
5016: * connection to the real X server.
5017: */
5018:
5019: /*
5020: * Check if it is a unix domain socket. Unix domain displays are in
5021: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
5022: */
1.25 markus 5023: if (strncmp(display, "unix:", 5) == 0 ||
5024: display[0] == ':') {
5025: /* Connect to the unix domain socket. */
1.367 djm 5026: if (sscanf(strrchr(display, ':') + 1, "%u",
5027: &display_number) != 1) {
5028: error("Could not parse display number from DISPLAY: "
5029: "%.100s", display);
1.51 markus 5030: return -1;
1.25 markus 5031: }
5032: /* Create a socket. */
5033: sock = connect_local_xsocket(display_number);
5034: if (sock < 0)
1.51 markus 5035: return -1;
1.25 markus 5036:
5037: /* OK, we now have a connection to the display. */
1.51 markus 5038: return sock;
1.25 markus 5039: }
1.27 markus 5040: /*
5041: * Connect to an inet socket. The DISPLAY value is supposedly
5042: * hostname:d[.s], where hostname may also be numeric IP address.
5043: */
1.145 stevesk 5044: strlcpy(buf, display, sizeof(buf));
1.25 markus 5045: cp = strchr(buf, ':');
5046: if (!cp) {
5047: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 5048: return -1;
1.25 markus 5049: }
5050: *cp = 0;
1.367 djm 5051: /*
5052: * buf now contains the host name. But first we parse the
5053: * display number.
5054: */
1.248 deraadt 5055: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 5056: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 5057: display);
1.51 markus 5058: return -1;
1.25 markus 5059: }
1.35 markus 5060:
5061: /* Look up the host address */
5062: memset(&hints, 0, sizeof(hints));
1.367 djm 5063: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 5064: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 5065: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 5066: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 5067: error("%.100s: unknown host. (%s)", buf,
5068: ssh_gai_strerror(gaierr));
1.51 markus 5069: return -1;
1.25 markus 5070: }
1.35 markus 5071: for (ai = aitop; ai; ai = ai->ai_next) {
5072: /* Create a socket. */
1.300 dtucker 5073: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 5074: if (sock == -1) {
1.194 markus 5075: debug2("socket: %.100s", strerror(errno));
1.41 markus 5076: continue;
5077: }
5078: /* Connect it to the display. */
1.393 deraadt 5079: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 5080: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 5081: 6000 + display_number, strerror(errno));
5082: close(sock);
5083: continue;
5084: }
5085: /* Success */
5086: break;
1.35 markus 5087: }
5088: freeaddrinfo(aitop);
5089: if (!ai) {
1.367 djm 5090: error("connect %.100s port %u: %.100s", buf,
5091: 6000 + display_number, strerror(errno));
1.51 markus 5092: return -1;
1.25 markus 5093: }
1.162 stevesk 5094: set_nodelay(sock);
1.51 markus 5095: return sock;
5096: }
5097:
5098: /*
1.27 markus 5099: * Requests forwarding of X11 connections, generates fake authentication
5100: * data, and enables authentication spoofing.
1.121 markus 5101: * This should be called in the client only.
1.27 markus 5102: */
1.49 markus 5103: void
1.367 djm 5104: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
5105: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 5106: {
1.367 djm 5107: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 5108: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 5109: u_int i, value;
1.367 djm 5110: const char *cp;
1.25 markus 5111: char *new_data;
1.367 djm 5112: int r, screen_number;
1.25 markus 5113:
1.367 djm 5114: if (sc->x11_saved_display == NULL)
5115: sc->x11_saved_display = xstrdup(disp);
5116: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 5117: error("x11_request_forwarding_with_spoofing: different "
5118: "$DISPLAY already forwarded");
5119: return;
5120: }
5121:
1.266 djm 5122: cp = strchr(disp, ':');
1.25 markus 5123: if (cp)
5124: cp = strchr(cp, '.');
5125: if (cp)
1.245 deraadt 5126: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 5127: else
5128: screen_number = 0;
5129:
1.367 djm 5130: if (sc->x11_saved_proto == NULL) {
1.219 djm 5131: /* Save protocol name. */
1.367 djm 5132: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 5133:
5134: /* Extract real authentication data. */
1.367 djm 5135: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 5136: for (i = 0; i < data_len; i++) {
1.403 djm 5137: if (sscanf(data + 2 * i, "%2x", &value) != 1) {
1.219 djm 5138: fatal("x11_request_forwarding: bad "
5139: "authentication data: %.100s", data);
1.403 djm 5140: }
1.367 djm 5141: sc->x11_saved_data[i] = value;
1.219 djm 5142: }
1.367 djm 5143: sc->x11_saved_data_len = data_len;
1.353 natano 5144:
5145: /* Generate fake data of the same length. */
1.367 djm 5146: sc->x11_fake_data = xmalloc(data_len);
5147: arc4random_buf(sc->x11_fake_data, data_len);
5148: sc->x11_fake_data_len = data_len;
1.25 markus 5149: }
5150:
5151: /* Convert the fake data into hex. */
1.367 djm 5152: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 5153:
5154: /* Send the request packet. */
1.367 djm 5155: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
5156: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
5157: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
5158: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
5159: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
5160: (r = sshpkt_send(ssh)) != 0 ||
5161: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 5162: fatal_fr(r, "send x11-req");
1.321 djm 5163: free(new_data);
1.1 deraadt 5164: }
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