Annotation of src/usr.bin/ssh/channels.c, Revision 1.418
1.418 ! markus 1: /* $OpenBSD: channels.c,v 1.417 2022/04/20 04:19:11 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:
1.367 djm 146: /* Master structure for channels state */
147: struct ssh_channels {
148: /*
149: * Pointer to an array containing all allocated channels. The array
150: * is dynamically extended as needed.
151: */
152: Channel **channels;
1.257 dtucker 153:
1.367 djm 154: /*
155: * Size of the channel array. All slots of the array must always be
156: * initialized (at least the type field); unused slots set to NULL
157: */
158: u_int channels_alloc;
1.257 dtucker 159:
1.367 djm 160: /*
1.411 djm 161: * 'channel_pre*' are called just before IO to add any bits
162: * relevant to channels in the c->io_want bitmasks.
1.367 djm 163: *
164: * 'channel_post*': perform any appropriate operations for
1.411 djm 165: * channels which have c->io_ready events pending.
1.367 djm 166: */
167: chan_fn **channel_pre;
168: chan_fn **channel_post;
1.314 dtucker 169:
1.367 djm 170: /* -- tcp forwarding */
1.381 djm 171: struct permission_set local_perms;
172: struct permission_set remote_perms;
1.219 djm 173:
1.367 djm 174: /* -- X11 forwarding */
1.121 markus 175:
1.367 djm 176: /* Saved X11 local (client) display. */
177: char *x11_saved_display;
1.121 markus 178:
1.367 djm 179: /* Saved X11 authentication protocol name. */
180: char *x11_saved_proto;
1.347 djm 181:
1.367 djm 182: /* Saved X11 authentication data. This is the real data. */
183: char *x11_saved_data;
184: u_int x11_saved_data_len;
1.121 markus 185:
1.367 djm 186: /* Deadline after which all X11 connections are refused */
187: u_int x11_refuse_time;
1.121 markus 188:
1.367 djm 189: /*
190: * Fake X11 authentication data. This is what the server will be
191: * sending us; we should replace any occurrences of this by the
192: * real data.
193: */
194: u_char *x11_fake_data;
195: u_int x11_fake_data_len;
1.121 markus 196:
1.367 djm 197: /* AF_UNSPEC or AF_INET or AF_INET6 */
198: int IPv4or6;
199: };
1.1 deraadt 200:
1.121 markus 201: /* helper */
1.367 djm 202: static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
1.354 markus 203: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 204:
1.276 djm 205: /* non-blocking connect helpers */
206: static int connect_next(struct channel_connect *);
207: static void channel_connect_ctx_free(struct channel_connect *);
1.372 markus 208: static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
209: static int rdynamic_connect_finish(struct ssh *, Channel *);
1.276 djm 210:
1.367 djm 211: /* Setup helper */
212: static void channel_handler_init(struct ssh_channels *sc);
213:
1.121 markus 214: /* -- channel core */
1.41 markus 215:
1.367 djm 216: void
217: channel_init_channels(struct ssh *ssh)
218: {
219: struct ssh_channels *sc;
220:
1.387 djm 221: if ((sc = calloc(1, sizeof(*sc))) == NULL)
1.403 djm 222: fatal_f("allocation failed");
1.367 djm 223: sc->channels_alloc = 10;
224: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
225: sc->IPv4or6 = AF_UNSPEC;
226: channel_handler_init(sc);
227:
228: ssh->chanctxt = sc;
229: }
230:
1.41 markus 231: Channel *
1.367 djm 232: channel_by_id(struct ssh *ssh, int id)
1.41 markus 233: {
234: Channel *c;
1.113 markus 235:
1.367 djm 236: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
1.403 djm 237: logit_f("%d: bad id", id);
1.41 markus 238: return NULL;
239: }
1.367 djm 240: c = ssh->chanctxt->channels[id];
1.113 markus 241: if (c == NULL) {
1.403 djm 242: logit_f("%d: bad id: channel free", id);
1.41 markus 243: return NULL;
244: }
245: return c;
1.55 markus 246: }
247:
1.354 markus 248: Channel *
1.368 djm 249: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 250: {
251: Channel *c;
252: u_int i;
253:
1.367 djm 254: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
255: c = ssh->chanctxt->channels[i];
1.368 djm 256: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 257: return c;
258: }
259: return NULL;
260: }
261:
1.27 markus 262: /*
1.229 markus 263: * Returns the channel if it is allowed to receive protocol messages.
264: * Private channels, like listening sockets, may not receive messages.
265: */
266: Channel *
1.367 djm 267: channel_lookup(struct ssh *ssh, int id)
1.229 markus 268: {
269: Channel *c;
270:
1.367 djm 271: if ((c = channel_by_id(ssh, id)) == NULL)
272: return NULL;
1.229 markus 273:
1.237 deraadt 274: switch (c->type) {
1.229 markus 275: case SSH_CHANNEL_X11_OPEN:
276: case SSH_CHANNEL_LARVAL:
277: case SSH_CHANNEL_CONNECTING:
278: case SSH_CHANNEL_DYNAMIC:
1.372 markus 279: case SSH_CHANNEL_RDYNAMIC_OPEN:
280: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 281: case SSH_CHANNEL_OPENING:
282: case SSH_CHANNEL_OPEN:
1.323 dtucker 283: case SSH_CHANNEL_ABANDONED:
1.354 markus 284: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 285: return c;
1.229 markus 286: }
287: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 288: return NULL;
1.229 markus 289: }
290:
291: /*
1.55 markus 292: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 293: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 294: */
1.127 itojun 295: static void
1.367 djm 296: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 297: int extusage, int nonblock, int is_tty)
1.1 deraadt 298: {
1.418 ! markus 299: int val;
! 300:
1.298 dtucker 301: if (rfd != -1)
302: fcntl(rfd, F_SETFD, FD_CLOEXEC);
303: if (wfd != -1 && wfd != rfd)
304: fcntl(wfd, F_SETFD, FD_CLOEXEC);
305: if (efd != -1 && efd != rfd && efd != wfd)
306: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 307:
1.52 markus 308: c->rfd = rfd;
309: c->wfd = wfd;
310: c->sock = (rfd == wfd) ? rfd : -1;
311: c->efd = efd;
312: c->extended_usage = extusage;
1.71 markus 313:
1.282 dtucker 314: if ((c->isatty = is_tty) != 0)
1.194 markus 315: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 316:
1.71 markus 317: /* enable nonblocking mode */
1.407 djm 318: c->restore_block = 0;
319: if (nonblock == CHANNEL_NONBLOCK_STDIO) {
320: /*
321: * Special handling for stdio file descriptors: do not set
322: * non-blocking mode if they are TTYs. Otherwise prepare to
323: * restore their blocking state on exit to avoid interfering
324: * with other programs that follow.
325: */
1.418 ! markus 326: if (rfd != -1 && !isatty(rfd) &&
! 327: (val = fcntl(rfd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) {
1.407 djm 328: c->restore_block |= CHANNEL_RESTORE_RFD;
329: set_nonblock(rfd);
330: }
1.418 ! markus 331: if (wfd != -1 && !isatty(wfd) &&
! 332: (val = fcntl(wfd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) {
1.407 djm 333: c->restore_block |= CHANNEL_RESTORE_WFD;
334: set_nonblock(wfd);
335: }
1.418 ! markus 336: if (efd != -1 && !isatty(efd) &&
! 337: (val = fcntl(efd, F_GETFL)) != -1 && !(val & O_NONBLOCK)) {
1.407 djm 338: c->restore_block |= CHANNEL_RESTORE_EFD;
339: set_nonblock(efd);
340: }
341: } else if (nonblock) {
1.71 markus 342: if (rfd != -1)
343: set_nonblock(rfd);
344: if (wfd != -1)
345: set_nonblock(wfd);
346: if (efd != -1)
347: set_nonblock(efd);
348: }
1.52 markus 349: }
350:
351: /*
352: * Allocate a new channel object and set its type and socket. This will cause
353: * remote_name to be freed.
354: */
1.113 markus 355: Channel *
1.367 djm 356: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 357: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 358: {
1.367 djm 359: struct ssh_channels *sc = ssh->chanctxt;
360: u_int i, found;
1.52 markus 361: Channel *c;
1.402 djm 362: int r;
1.25 markus 363:
364: /* Try to find a free slot where to put the new channel. */
1.367 djm 365: for (i = 0; i < sc->channels_alloc; i++) {
366: if (sc->channels[i] == NULL) {
1.25 markus 367: /* Found a free slot. */
1.367 djm 368: found = i;
1.25 markus 369: break;
370: }
1.367 djm 371: }
372: if (i >= sc->channels_alloc) {
373: /*
374: * There are no free slots. Take last+1 slot and expand
375: * the array.
376: */
377: found = sc->channels_alloc;
378: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
1.403 djm 379: fatal_f("internal error: channels_alloc %d too big",
380: sc->channels_alloc);
1.367 djm 381: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
382: sc->channels_alloc + 10, sizeof(*sc->channels));
383: sc->channels_alloc += 10;
384: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 385: }
1.113 markus 386: /* Initialize and return new channel. */
1.367 djm 387: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
388: if ((c->input = sshbuf_new()) == NULL ||
389: (c->output = sshbuf_new()) == NULL ||
390: (c->extended = sshbuf_new()) == NULL)
1.403 djm 391: fatal_f("sshbuf_new failed");
1.402 djm 392: if ((r = sshbuf_set_max_size(c->input, CHAN_INPUT_MAX)) != 0)
1.403 djm 393: fatal_fr(r, "sshbuf_set_max_size");
1.159 markus 394: c->ostate = CHAN_OUTPUT_OPEN;
395: c->istate = CHAN_INPUT_OPEN;
1.367 djm 396: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 397: c->self = found;
398: c->type = type;
1.41 markus 399: c->ctype = ctype;
1.51 markus 400: c->local_window = window;
401: c->local_window_max = window;
402: c->local_maxpacket = maxpack;
1.190 markus 403: c->remote_name = xstrdup(remote_name);
1.302 djm 404: c->ctl_chan = -1;
1.299 markus 405: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 406: TAILQ_INIT(&c->status_confirms);
1.25 markus 407: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 408: return c;
1.1 deraadt 409: }
1.52 markus 410:
1.132 markus 411: int
1.407 djm 412: channel_close_fd(struct ssh *ssh, Channel *c, int *fdp)
1.132 markus 413: {
1.407 djm 414: int ret, fd = *fdp;
1.132 markus 415:
1.407 djm 416: if (fd == -1)
417: return 0;
418:
419: if ((*fdp == c->rfd && (c->restore_block & CHANNEL_RESTORE_RFD) != 0) ||
420: (*fdp == c->wfd && (c->restore_block & CHANNEL_RESTORE_WFD) != 0) ||
421: (*fdp == c->efd && (c->restore_block & CHANNEL_RESTORE_EFD) != 0))
422: (void)fcntl(*fdp, F_SETFL, 0); /* restore blocking */
423:
1.411 djm 424: if (*fdp == c->rfd) {
425: c->io_want &= ~SSH_CHAN_IO_RFD;
426: c->io_ready &= ~SSH_CHAN_IO_RFD;
427: c->rfd = -1;
1.415 djm 428: c->pfds[0] = -1;
1.411 djm 429: }
430: if (*fdp == c->wfd) {
431: c->io_want &= ~SSH_CHAN_IO_WFD;
432: c->io_ready &= ~SSH_CHAN_IO_WFD;
433: c->wfd = -1;
1.415 djm 434: c->pfds[1] = -1;
1.411 djm 435: }
436: if (*fdp == c->efd) {
437: c->io_want &= ~SSH_CHAN_IO_EFD;
438: c->io_ready &= ~SSH_CHAN_IO_EFD;
439: c->efd = -1;
1.415 djm 440: c->pfds[2] = -1;
1.411 djm 441: }
442: if (*fdp == c->sock) {
443: c->io_want &= ~SSH_CHAN_IO_SOCK;
444: c->io_ready &= ~SSH_CHAN_IO_SOCK;
445: c->sock = -1;
1.415 djm 446: c->pfds[3] = -1;
1.411 djm 447: }
448:
1.407 djm 449: ret = close(fd);
1.411 djm 450: *fdp = -1; /* probably redundant */
1.132 markus 451: return ret;
452: }
453:
1.52 markus 454: /* Close all channel fd/socket. */
1.127 itojun 455: static void
1.367 djm 456: channel_close_fds(struct ssh *ssh, Channel *c)
457: {
1.379 tb 458: int sock = c->sock, rfd = c->rfd, wfd = c->wfd, efd = c->efd;
459:
1.407 djm 460: channel_close_fd(ssh, c, &c->sock);
1.379 tb 461: if (rfd != sock)
1.407 djm 462: channel_close_fd(ssh, c, &c->rfd);
1.379 tb 463: if (wfd != sock && wfd != rfd)
1.407 djm 464: channel_close_fd(ssh, c, &c->wfd);
1.379 tb 465: if (efd != sock && efd != rfd && efd != wfd)
1.407 djm 466: channel_close_fd(ssh, c, &c->efd);
1.367 djm 467: }
468:
469: static void
1.381 djm 470: fwd_perm_clear(struct permission *perm)
1.52 markus 471: {
1.381 djm 472: free(perm->host_to_connect);
473: free(perm->listen_host);
474: free(perm->listen_path);
1.398 dtucker 475: memset(perm, 0, sizeof(*perm));
1.367 djm 476: }
477:
1.381 djm 478: /* Returns an printable name for the specified forwarding permission list */
479: static const char *
480: fwd_ident(int who, int where)
481: {
482: if (who == FORWARD_ADM) {
483: if (where == FORWARD_LOCAL)
484: return "admin local";
485: else if (where == FORWARD_REMOTE)
486: return "admin remote";
487: } else if (who == FORWARD_USER) {
488: if (where == FORWARD_LOCAL)
489: return "user local";
490: else if (where == FORWARD_REMOTE)
491: return "user remote";
492: }
493: fatal("Unknown forward permission list %d/%d", who, where);
494: }
495:
496: /* Returns the forwarding permission list for the specified direction */
497: static struct permission_set *
498: permission_set_get(struct ssh *ssh, int where)
499: {
500: struct ssh_channels *sc = ssh->chanctxt;
1.367 djm 501:
1.381 djm 502: switch (where) {
503: case FORWARD_LOCAL:
504: return &sc->local_perms;
505: break;
506: case FORWARD_REMOTE:
507: return &sc->remote_perms;
508: break;
509: default:
1.403 djm 510: fatal_f("invalid forwarding direction %d", where);
1.381 djm 511: }
512: }
513:
1.392 dtucker 514: /* Returns pointers to the specified forwarding list and its element count */
1.381 djm 515: static void
516: permission_set_get_array(struct ssh *ssh, int who, int where,
517: struct permission ***permpp, u_int **npermpp)
518: {
519: struct permission_set *pset = permission_set_get(ssh, where);
520:
521: switch (who) {
522: case FORWARD_USER:
523: *permpp = &pset->permitted_user;
524: *npermpp = &pset->num_permitted_user;
525: break;
526: case FORWARD_ADM:
527: *permpp = &pset->permitted_admin;
528: *npermpp = &pset->num_permitted_admin;
529: break;
530: default:
1.403 djm 531: fatal_f("invalid forwarding client %d", who);
1.381 djm 532: }
533: }
534:
1.409 jsg 535: /* Adds an entry to the specified forwarding list */
1.367 djm 536: static int
1.381 djm 537: permission_set_add(struct ssh *ssh, int who, int where,
1.367 djm 538: const char *host_to_connect, int port_to_connect,
539: const char *listen_host, const char *listen_path, int listen_port,
540: Channel *downstream)
541: {
1.381 djm 542: struct permission **permp;
543: u_int n, *npermp;
1.367 djm 544:
1.381 djm 545: permission_set_get_array(ssh, who, where, &permp, &npermp);
1.367 djm 546:
1.381 djm 547: if (*npermp >= INT_MAX)
1.403 djm 548: fatal_f("%s overflow", fwd_ident(who, where));
1.367 djm 549:
1.381 djm 550: *permp = xrecallocarray(*permp, *npermp, *npermp + 1, sizeof(**permp));
551: n = (*npermp)++;
1.367 djm 552: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
1.381 djm 553: (*permp)[n].host_to_connect = MAYBE_DUP(host_to_connect);
554: (*permp)[n].port_to_connect = port_to_connect;
555: (*permp)[n].listen_host = MAYBE_DUP(listen_host);
556: (*permp)[n].listen_path = MAYBE_DUP(listen_path);
557: (*permp)[n].listen_port = listen_port;
558: (*permp)[n].downstream = downstream;
1.367 djm 559: #undef MAYBE_DUP
560: return (int)n;
561: }
562:
563: static void
564: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
565: {
566: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 567: struct permission_set *pset = &sc->local_perms;
568: struct permission *perm;
1.367 djm 569: int r;
570: u_int i;
571:
1.381 djm 572: for (i = 0; i < pset->num_permitted_user; i++) {
573: perm = &pset->permitted_user[i];
574: if (perm->downstream != c)
1.367 djm 575: continue;
576:
577: /* cancel on the server, since mux client is gone */
578: debug("channel %d: cleanup remote forward for %s:%u",
1.381 djm 579: c->self, perm->listen_host, perm->listen_port);
1.367 djm 580: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
581: (r = sshpkt_put_cstring(ssh,
582: "cancel-tcpip-forward")) != 0 ||
583: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
584: (r = sshpkt_put_cstring(ssh,
1.381 djm 585: channel_rfwd_bind_host(perm->listen_host))) != 0 ||
586: (r = sshpkt_put_u32(ssh, perm->listen_port)) != 0 ||
1.367 djm 587: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 588: fatal_fr(r, "channel %i", c->self);
1.367 djm 589: }
1.381 djm 590: fwd_perm_clear(perm); /* unregister */
1.367 djm 591: }
1.121 markus 592: }
593:
594: /* Free the channel and close its fd/socket. */
595: void
1.367 djm 596: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 597: {
1.367 djm 598: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 599: char *s;
1.209 avsm 600: u_int i, n;
1.354 markus 601: Channel *other;
1.275 djm 602: struct channel_confirm *cc;
1.121 markus 603:
1.367 djm 604: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
605: if ((other = sc->channels[i]) == NULL)
606: continue;
607: n++;
608: /* detach from mux client and prepare for closing */
609: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
610: other->type == SSH_CHANNEL_MUX_PROXY &&
611: other->mux_ctx == c) {
612: other->mux_ctx = NULL;
613: other->type = SSH_CHANNEL_OPEN;
614: other->istate = CHAN_INPUT_CLOSED;
615: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 616: }
617: }
1.209 avsm 618: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 619: c->remote_name ? c->remote_name : "???", n);
620:
1.408 mbuhl 621: if (c->type == SSH_CHANNEL_MUX_CLIENT) {
1.367 djm 622: mux_remove_remote_forwardings(ssh, c);
1.408 mbuhl 623: free(c->mux_ctx);
624: c->mux_ctx = NULL;
625: } else if (c->type == SSH_CHANNEL_MUX_LISTENER) {
1.401 djm 626: free(c->mux_ctx);
627: c->mux_ctx = NULL;
628: }
1.354 markus 629:
1.384 markus 630: if (log_level_get() >= SYSLOG_LEVEL_DEBUG3) {
631: s = channel_open_message(ssh);
632: debug3("channel %d: status: %s", c->self, s);
633: free(s);
634: }
1.121 markus 635:
1.367 djm 636: channel_close_fds(ssh, c);
637: sshbuf_free(c->input);
638: sshbuf_free(c->output);
639: sshbuf_free(c->extended);
640: c->input = c->output = c->extended = NULL;
1.321 djm 641: free(c->remote_name);
642: c->remote_name = NULL;
643: free(c->path);
644: c->path = NULL;
645: free(c->listening_addr);
646: c->listening_addr = NULL;
1.275 djm 647: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
648: if (cc->abandon_cb != NULL)
1.367 djm 649: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 650: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 651: freezero(cc, sizeof(*cc));
1.275 djm 652: }
1.280 djm 653: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 654: c->filter_cleanup(ssh, c->self, c->filter_ctx);
655: sc->channels[c->self] = NULL;
1.396 jsg 656: freezero(c, sizeof(*c));
1.121 markus 657: }
658:
659: void
1.367 djm 660: channel_free_all(struct ssh *ssh)
1.121 markus 661: {
1.209 avsm 662: u_int i;
1.390 dtucker 663: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 664:
1.390 dtucker 665: for (i = 0; i < sc->channels_alloc; i++)
666: if (sc->channels[i] != NULL)
667: channel_free(ssh, sc->channels[i]);
668:
669: free(sc->channels);
670: sc->channels = NULL;
671: sc->channels_alloc = 0;
672:
673: free(sc->x11_saved_display);
674: sc->x11_saved_display = NULL;
675:
676: free(sc->x11_saved_proto);
677: sc->x11_saved_proto = NULL;
678:
679: free(sc->x11_saved_data);
680: sc->x11_saved_data = NULL;
681: sc->x11_saved_data_len = 0;
682:
683: free(sc->x11_fake_data);
684: sc->x11_fake_data = NULL;
685: sc->x11_fake_data_len = 0;
1.131 markus 686: }
687:
1.121 markus 688: /*
689: * Closes the sockets/fds of all channels. This is used to close extra file
690: * descriptors after a fork.
691: */
692: void
1.367 djm 693: channel_close_all(struct ssh *ssh)
1.121 markus 694: {
1.209 avsm 695: u_int i;
1.121 markus 696:
1.367 djm 697: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
698: if (ssh->chanctxt->channels[i] != NULL)
699: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 700: }
701:
702: /*
1.131 markus 703: * Stop listening to channels.
704: */
705: void
1.367 djm 706: channel_stop_listening(struct ssh *ssh)
1.131 markus 707: {
1.209 avsm 708: u_int i;
1.131 markus 709: Channel *c;
710:
1.367 djm 711: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
712: c = ssh->chanctxt->channels[i];
1.131 markus 713: if (c != NULL) {
714: switch (c->type) {
715: case SSH_CHANNEL_AUTH_SOCKET:
716: case SSH_CHANNEL_PORT_LISTENER:
717: case SSH_CHANNEL_RPORT_LISTENER:
718: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 719: case SSH_CHANNEL_UNIX_LISTENER:
720: case SSH_CHANNEL_RUNIX_LISTENER:
1.407 djm 721: channel_close_fd(ssh, c, &c->sock);
1.367 djm 722: channel_free(ssh, c);
1.131 markus 723: break;
724: }
725: }
726: }
727: }
728:
729: /*
1.121 markus 730: * Returns true if no channel has too much buffered data, and false if one or
731: * more channel is overfull.
732: */
733: int
1.367 djm 734: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 735: {
736: u_int i;
1.367 djm 737: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 738: Channel *c;
739:
1.367 djm 740: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
741: c = ssh->chanctxt->channels[i];
742: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
743: continue;
744: if (sshbuf_len(c->output) > maxsize) {
745: debug2("channel %d: big output buffer %zu > %u",
746: c->self, sshbuf_len(c->output), maxsize);
747: return 0;
1.121 markus 748: }
749: }
750: return 1;
751: }
752:
753: /* Returns true if any channel is still open. */
754: int
1.367 djm 755: channel_still_open(struct ssh *ssh)
1.121 markus 756: {
1.209 avsm 757: u_int i;
1.121 markus 758: Channel *c;
759:
1.367 djm 760: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
761: c = ssh->chanctxt->channels[i];
1.121 markus 762: if (c == NULL)
763: continue;
764: switch (c->type) {
765: case SSH_CHANNEL_X11_LISTENER:
766: case SSH_CHANNEL_PORT_LISTENER:
767: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 768: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 769: case SSH_CHANNEL_CLOSED:
770: case SSH_CHANNEL_AUTH_SOCKET:
771: case SSH_CHANNEL_DYNAMIC:
1.372 markus 772: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 773: case SSH_CHANNEL_CONNECTING:
774: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 775: case SSH_CHANNEL_ABANDONED:
1.336 millert 776: case SSH_CHANNEL_UNIX_LISTENER:
777: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 778: continue;
779: case SSH_CHANNEL_LARVAL:
780: continue;
781: case SSH_CHANNEL_OPENING:
782: case SSH_CHANNEL_OPEN:
1.372 markus 783: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 784: case SSH_CHANNEL_X11_OPEN:
1.302 djm 785: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 786: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 787: return 1;
788: default:
1.403 djm 789: fatal_f("bad channel type %d", c->type);
1.121 markus 790: /* NOTREACHED */
791: }
792: }
793: return 0;
794: }
795:
796: /* Returns the id of an open channel suitable for keepaliving */
797: int
1.367 djm 798: channel_find_open(struct ssh *ssh)
1.121 markus 799: {
1.209 avsm 800: u_int i;
1.121 markus 801: Channel *c;
802:
1.367 djm 803: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
804: c = ssh->chanctxt->channels[i];
1.368 djm 805: if (c == NULL || !c->have_remote_id)
1.121 markus 806: continue;
807: switch (c->type) {
808: case SSH_CHANNEL_CLOSED:
809: case SSH_CHANNEL_DYNAMIC:
1.372 markus 810: case SSH_CHANNEL_RDYNAMIC_OPEN:
811: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 812: case SSH_CHANNEL_X11_LISTENER:
813: case SSH_CHANNEL_PORT_LISTENER:
814: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 815: case SSH_CHANNEL_MUX_LISTENER:
816: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 817: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 818: case SSH_CHANNEL_OPENING:
819: case SSH_CHANNEL_CONNECTING:
820: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 821: case SSH_CHANNEL_ABANDONED:
1.336 millert 822: case SSH_CHANNEL_UNIX_LISTENER:
823: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 824: continue;
825: case SSH_CHANNEL_LARVAL:
826: case SSH_CHANNEL_AUTH_SOCKET:
827: case SSH_CHANNEL_OPEN:
828: case SSH_CHANNEL_X11_OPEN:
829: return i;
830: default:
1.403 djm 831: fatal_f("bad channel type %d", c->type);
1.121 markus 832: /* NOTREACHED */
833: }
834: }
835: return -1;
836: }
837:
1.385 djm 838: /* Returns the state of the channel's extended usage flag */
839: const char *
840: channel_format_extended_usage(const Channel *c)
841: {
842: if (c->efd == -1)
843: return "closed";
844:
845: switch (c->extended_usage) {
846: case CHAN_EXTENDED_WRITE:
847: return "write";
848: case CHAN_EXTENDED_READ:
849: return "read";
850: case CHAN_EXTENDED_IGNORE:
851: return "ignore";
852: default:
853: return "UNKNOWN";
854: }
855: }
856:
1.386 djm 857: static char *
858: channel_format_status(const Channel *c)
859: {
860: char *ret = NULL;
861:
862: xasprintf(&ret, "t%d %s%u i%u/%zu o%u/%zu e[%s]/%zu "
1.411 djm 863: "fd %d/%d/%d sock %d cc %d io 0x%02x/0x%02x",
1.386 djm 864: c->type,
865: c->have_remote_id ? "r" : "nr", c->remote_id,
866: c->istate, sshbuf_len(c->input),
867: c->ostate, sshbuf_len(c->output),
868: channel_format_extended_usage(c), sshbuf_len(c->extended),
1.411 djm 869: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan,
870: c->io_want, c->io_ready);
1.386 djm 871: return ret;
872: }
873:
1.121 markus 874: /*
875: * Returns a message describing the currently open forwarded connections,
876: * suitable for sending to the client. The message contains crlf pairs for
877: * newlines.
878: */
879: char *
1.367 djm 880: channel_open_message(struct ssh *ssh)
1.121 markus 881: {
1.367 djm 882: struct sshbuf *buf;
1.121 markus 883: Channel *c;
1.209 avsm 884: u_int i;
1.367 djm 885: int r;
1.386 djm 886: char *cp, *ret;
1.121 markus 887:
1.367 djm 888: if ((buf = sshbuf_new()) == NULL)
1.403 djm 889: fatal_f("sshbuf_new");
1.367 djm 890: if ((r = sshbuf_putf(buf,
891: "The following connections are open:\r\n")) != 0)
1.403 djm 892: fatal_fr(r, "sshbuf_putf");
1.367 djm 893: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
894: c = ssh->chanctxt->channels[i];
1.121 markus 895: if (c == NULL)
896: continue;
897: switch (c->type) {
898: case SSH_CHANNEL_X11_LISTENER:
899: case SSH_CHANNEL_PORT_LISTENER:
900: case SSH_CHANNEL_RPORT_LISTENER:
901: case SSH_CHANNEL_CLOSED:
902: case SSH_CHANNEL_AUTH_SOCKET:
903: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 904: case SSH_CHANNEL_ABANDONED:
1.302 djm 905: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 906: case SSH_CHANNEL_UNIX_LISTENER:
907: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 908: continue;
909: case SSH_CHANNEL_LARVAL:
910: case SSH_CHANNEL_OPENING:
911: case SSH_CHANNEL_CONNECTING:
912: case SSH_CHANNEL_DYNAMIC:
1.372 markus 913: case SSH_CHANNEL_RDYNAMIC_OPEN:
914: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 915: case SSH_CHANNEL_OPEN:
916: case SSH_CHANNEL_X11_OPEN:
1.354 markus 917: case SSH_CHANNEL_MUX_PROXY:
918: case SSH_CHANNEL_MUX_CLIENT:
1.386 djm 919: cp = channel_format_status(c);
920: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
921: c->self, c->remote_name, cp)) != 0) {
922: free(cp);
1.403 djm 923: fatal_fr(r, "sshbuf_putf");
1.386 djm 924: }
925: free(cp);
1.121 markus 926: continue;
927: default:
1.403 djm 928: fatal_f("bad channel type %d", c->type);
1.121 markus 929: /* NOTREACHED */
930: }
931: }
1.367 djm 932: if ((ret = sshbuf_dup_string(buf)) == NULL)
1.403 djm 933: fatal_f("sshbuf_dup_string");
1.367 djm 934: sshbuf_free(buf);
935: return ret;
936: }
937:
938: static void
939: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
940: {
941: int r;
942:
943: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
944: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
945: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
946: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
947: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
1.403 djm 948: fatal_r(r, "%s: channel %i: open", where, c->self);
1.367 djm 949: }
1.121 markus 950: }
951:
952: void
1.367 djm 953: channel_send_open(struct ssh *ssh, int id)
1.121 markus 954: {
1.367 djm 955: Channel *c = channel_lookup(ssh, id);
956: int r;
1.180 deraadt 957:
1.121 markus 958: if (c == NULL) {
1.188 itojun 959: logit("channel_send_open: %d: bad id", id);
1.121 markus 960: return;
961: }
1.184 markus 962: debug2("channel %d: send open", id);
1.367 djm 963: open_preamble(ssh, __func__, c, c->ctype);
964: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 965: fatal_fr(r, "channel %i", c->self);
1.121 markus 966: }
967:
968: void
1.367 djm 969: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 970: {
1.367 djm 971: Channel *c = channel_lookup(ssh, id);
972: int r;
1.180 deraadt 973:
1.121 markus 974: if (c == NULL) {
1.403 djm 975: logit_f("%d: unknown channel id", id);
1.121 markus 976: return;
977: }
1.368 djm 978: if (!c->have_remote_id)
1.403 djm 979: fatal_f("channel %d: no remote id", c->self);
1.368 djm 980:
1.204 djm 981: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 982: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
983: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
984: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
985: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
1.403 djm 986: fatal_fr(r, "channel %i", c->self);
1.367 djm 987: }
1.121 markus 988: }
1.241 deraadt 989:
1.121 markus 990: void
1.367 djm 991: channel_register_status_confirm(struct ssh *ssh, int id,
992: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 993: {
994: struct channel_confirm *cc;
995: Channel *c;
996:
1.367 djm 997: if ((c = channel_lookup(ssh, id)) == NULL)
1.403 djm 998: fatal_f("%d: bad id", id);
1.275 djm 999:
1.327 djm 1000: cc = xcalloc(1, sizeof(*cc));
1.275 djm 1001: cc->cb = cb;
1002: cc->abandon_cb = abandon_cb;
1003: cc->ctx = ctx;
1004: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
1005: }
1006:
1007: void
1.367 djm 1008: channel_register_open_confirm(struct ssh *ssh, int id,
1009: channel_open_fn *fn, void *ctx)
1.121 markus 1010: {
1.367 djm 1011: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1012:
1.121 markus 1013: if (c == NULL) {
1.403 djm 1014: logit_f("%d: bad id", id);
1.121 markus 1015: return;
1016: }
1.275 djm 1017: c->open_confirm = fn;
1018: c->open_confirm_ctx = ctx;
1.121 markus 1019: }
1.241 deraadt 1020:
1.121 markus 1021: void
1.367 djm 1022: channel_register_cleanup(struct ssh *ssh, int id,
1023: channel_callback_fn *fn, int do_close)
1.121 markus 1024: {
1.367 djm 1025: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1026:
1.121 markus 1027: if (c == NULL) {
1.403 djm 1028: logit_f("%d: bad id", id);
1.121 markus 1029: return;
1030: }
1.131 markus 1031: c->detach_user = fn;
1.225 djm 1032: c->detach_close = do_close;
1.121 markus 1033: }
1.241 deraadt 1034:
1.121 markus 1035: void
1.367 djm 1036: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 1037: {
1.367 djm 1038: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1039:
1.121 markus 1040: if (c == NULL) {
1.403 djm 1041: logit_f("%d: bad id", id);
1.121 markus 1042: return;
1.52 markus 1043: }
1.131 markus 1044: c->detach_user = NULL;
1.225 djm 1045: c->detach_close = 0;
1.121 markus 1046: }
1.241 deraadt 1047:
1.121 markus 1048: void
1.367 djm 1049: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1050: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1051: {
1.367 djm 1052: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1053:
1.121 markus 1054: if (c == NULL) {
1.403 djm 1055: logit_f("%d: bad id", id);
1.121 markus 1056: return;
1.52 markus 1057: }
1.231 reyk 1058: c->input_filter = ifn;
1059: c->output_filter = ofn;
1.279 djm 1060: c->filter_ctx = ctx;
1.280 djm 1061: c->filter_cleanup = cfn;
1.52 markus 1062: }
1063:
1.49 markus 1064: void
1.367 djm 1065: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1066: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1067: {
1.367 djm 1068: Channel *c = channel_lookup(ssh, id);
1069: int r;
1.180 deraadt 1070:
1.121 markus 1071: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1072: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1073: if (!c->have_remote_id)
1.403 djm 1074: fatal_f("channel %d: no remote id", c->self);
1.368 djm 1075:
1.367 djm 1076: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1077: c->type = SSH_CHANNEL_OPEN;
1.168 markus 1078: c->local_window = c->local_window_max = window_max;
1.367 djm 1079:
1080: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1081: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1082: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1083: (r = sshpkt_send(ssh)) != 0)
1.403 djm 1084: fatal_fr(r, "channel %i", c->self);
1.1 deraadt 1085: }
1086:
1.127 itojun 1087: static void
1.410 djm 1088: channel_pre_listener(struct ssh *ssh, Channel *c)
1.41 markus 1089: {
1.410 djm 1090: c->io_want = SSH_CHAN_IO_SOCK_R;
1.41 markus 1091: }
1092:
1.127 itojun 1093: static void
1.410 djm 1094: channel_pre_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1095: {
1096: debug3("channel %d: waiting for connection", c->self);
1.410 djm 1097: c->io_want = SSH_CHAN_IO_SOCK_W;
1.75 markus 1098: }
1099:
1.127 itojun 1100: static void
1.410 djm 1101: channel_pre_open(struct ssh *ssh, Channel *c)
1.41 markus 1102: {
1.410 djm 1103: c->io_want = 0;
1.44 markus 1104: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1105: c->remote_window > 0 &&
1.367 djm 1106: sshbuf_len(c->input) < c->remote_window &&
1107: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1108: c->io_want |= SSH_CHAN_IO_RFD;
1.44 markus 1109: if (c->ostate == CHAN_OUTPUT_OPEN ||
1110: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1111: if (sshbuf_len(c->output) > 0) {
1.410 djm 1112: c->io_want |= SSH_CHAN_IO_WFD;
1.44 markus 1113: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1114: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1115: debug2("channel %d: "
1116: "obuf_empty delayed efd %d/(%zu)", c->self,
1117: c->efd, sshbuf_len(c->extended));
1.172 markus 1118: else
1.367 djm 1119: chan_obuf_empty(ssh, c);
1.44 markus 1120: }
1121: }
1122: /** XXX check close conditions, too */
1.358 djm 1123: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1124: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1125: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1126: sshbuf_len(c->extended) > 0)
1.410 djm 1127: c->io_want |= SSH_CHAN_IO_EFD_W;
1.306 djm 1128: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1129: (c->extended_usage == CHAN_EXTENDED_READ ||
1130: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1131: sshbuf_len(c->extended) < c->remote_window)
1.410 djm 1132: c->io_want |= SSH_CHAN_IO_EFD_R;
1.44 markus 1133: }
1.204 djm 1134: /* XXX: What about efd? races? */
1.44 markus 1135: }
1136:
1.41 markus 1137: /*
1138: * This is a special state for X11 authentication spoofing. An opened X11
1139: * connection (when authentication spoofing is being done) remains in this
1140: * state until the first packet has been completely read. The authentication
1141: * data in that packet is then substituted by the real data if it matches the
1142: * fake data, and the channel is put into normal mode.
1.51 markus 1143: * XXX All this happens at the client side.
1.121 markus 1144: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1145: */
1.127 itojun 1146: static int
1.367 djm 1147: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1148: {
1.367 djm 1149: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1150: u_char *ucp;
1151: u_int proto_len, data_len;
1.25 markus 1152:
1.347 djm 1153: /* Is this being called after the refusal deadline? */
1.367 djm 1154: if (sc->x11_refuse_time != 0 &&
1155: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1156: verbose("Rejected X11 connection after ForwardX11Timeout "
1157: "expired");
1158: return -1;
1159: }
1160:
1.41 markus 1161: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1162: if (sshbuf_len(b) < 12)
1.41 markus 1163: return 0;
1164:
1165: /* Parse the lengths of variable-length fields. */
1.367 djm 1166: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1167: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1168: proto_len = 256 * ucp[6] + ucp[7];
1169: data_len = 256 * ucp[8] + ucp[9];
1170: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1171: proto_len = ucp[6] + 256 * ucp[7];
1172: data_len = ucp[8] + 256 * ucp[9];
1173: } else {
1.194 markus 1174: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1175: ucp[0]);
1.41 markus 1176: return -1;
1177: }
1178:
1179: /* Check if the whole packet is in buffer. */
1.367 djm 1180: if (sshbuf_len(b) <
1.41 markus 1181: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1182: return 0;
1183:
1184: /* Check if authentication protocol matches. */
1.367 djm 1185: if (proto_len != strlen(sc->x11_saved_proto) ||
1186: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1187: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1188: return -1;
1189: }
1190: /* Check if authentication data matches our fake data. */
1.367 djm 1191: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1192: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1193: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1194: debug2("X11 auth data does not match fake data.");
1.41 markus 1195: return -1;
1196: }
1197: /* Check fake data length */
1.367 djm 1198: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1199: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1200: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1201: return -1;
1202: }
1203: /*
1204: * Received authentication protocol and data match
1205: * our fake data. Substitute the fake data with real
1206: * data.
1207: */
1208: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1209: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1210: return 1;
1211: }
1212:
1.127 itojun 1213: static void
1.410 djm 1214: channel_pre_x11_open(struct ssh *ssh, Channel *c)
1.41 markus 1215: {
1.367 djm 1216: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1217:
1218: /* c->force_drain = 1; */
1219:
1.41 markus 1220: if (ret == 1) {
1221: c->type = SSH_CHANNEL_OPEN;
1.410 djm 1222: channel_pre_open(ssh, c);
1.41 markus 1223: } else if (ret == -1) {
1.188 itojun 1224: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1225: debug2("X11 rejected %d i%d/o%d",
1226: c->self, c->istate, c->ostate);
1227: chan_read_failed(ssh, c);
1228: sshbuf_reset(c->input);
1229: chan_ibuf_empty(ssh, c);
1230: sshbuf_reset(c->output);
1231: chan_write_failed(ssh, c);
1.194 markus 1232: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1233: }
1234: }
1.25 markus 1235:
1.302 djm 1236: static void
1.410 djm 1237: channel_pre_mux_client(struct ssh *ssh, Channel *c)
1.302 djm 1238: {
1.410 djm 1239: c->io_want = 0;
1.304 djm 1240: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1241: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1242: c->io_want |= SSH_CHAN_IO_RFD;
1.302 djm 1243: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1244: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1245: sshbuf_reset(c->input);
1246: chan_ibuf_empty(ssh, c);
1.302 djm 1247: /* Start output drain. XXX just kill chan? */
1.367 djm 1248: chan_rcvd_oclose(ssh, c);
1.302 djm 1249: }
1250: if (c->ostate == CHAN_OUTPUT_OPEN ||
1251: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1252: if (sshbuf_len(c->output) > 0)
1.410 djm 1253: c->io_want |= SSH_CHAN_IO_WFD;
1.302 djm 1254: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1255: chan_obuf_empty(ssh, c);
1.302 djm 1256: }
1257: }
1258:
1.104 markus 1259: /* try to decode a socks4 header */
1.127 itojun 1260: static int
1.372 markus 1261: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1262: {
1.367 djm 1263: const u_char *p;
1264: char *host;
1.292 djm 1265: u_int len, have, i, found, need;
1.148 deraadt 1266: char username[256];
1.103 markus 1267: struct {
1268: u_int8_t version;
1269: u_int8_t command;
1270: u_int16_t dest_port;
1.104 markus 1271: struct in_addr dest_addr;
1.103 markus 1272: } s4_req, s4_rsp;
1.367 djm 1273: int r;
1.103 markus 1274:
1.104 markus 1275: debug2("channel %d: decode socks4", c->self);
1.109 markus 1276:
1.372 markus 1277: have = sshbuf_len(input);
1.109 markus 1278: len = sizeof(s4_req);
1279: if (have < len)
1280: return 0;
1.372 markus 1281: p = sshbuf_ptr(input);
1.292 djm 1282:
1283: need = 1;
1284: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1285: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1286: debug2("channel %d: socks4a request", c->self);
1287: /* ... and needs an extra string (the hostname) */
1288: need = 2;
1289: }
1290: /* Check for terminating NUL on the string(s) */
1.109 markus 1291: for (found = 0, i = len; i < have; i++) {
1292: if (p[i] == '\0') {
1.292 djm 1293: found++;
1294: if (found == need)
1295: break;
1.109 markus 1296: }
1297: if (i > 1024) {
1298: /* the peer is probably sending garbage */
1299: debug("channel %d: decode socks4: too long",
1300: c->self);
1301: return -1;
1302: }
1303: }
1.292 djm 1304: if (found < need)
1.109 markus 1305: return 0;
1.372 markus 1306: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1307: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1308: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1309: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.403 djm 1310: debug_r(r, "channels %d: decode socks4", c->self);
1.367 djm 1311: return -1;
1312: }
1.372 markus 1313: have = sshbuf_len(input);
1314: p = sshbuf_ptr(input);
1.364 djm 1315: if (memchr(p, '\0', have) == NULL) {
1.403 djm 1316: error("channel %d: decode socks4: unterminated user", c->self);
1.364 djm 1317: return -1;
1318: }
1.103 markus 1319: len = strlen(p);
1.106 markus 1320: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1321: len++; /* trailing '\0' */
1.103 markus 1322: strlcpy(username, p, sizeof(username));
1.403 djm 1323: if ((r = sshbuf_consume(input, len)) != 0)
1324: fatal_fr(r, "channel %d: consume", c->self);
1.321 djm 1325: free(c->path);
1326: c->path = NULL;
1.292 djm 1327: if (need == 1) { /* SOCKS4: one string */
1328: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1329: c->path = xstrdup(host);
1.292 djm 1330: } else { /* SOCKS4A: two strings */
1.372 markus 1331: have = sshbuf_len(input);
1332: p = sshbuf_ptr(input);
1.364 djm 1333: if (memchr(p, '\0', have) == NULL) {
1334: error("channel %d: decode socks4a: host not nul "
1335: "terminated", c->self);
1336: return -1;
1337: }
1.292 djm 1338: len = strlen(p);
1339: debug2("channel %d: decode socks4a: host %s/%d",
1340: c->self, p, len);
1341: len++; /* trailing '\0' */
1.293 djm 1342: if (len > NI_MAXHOST) {
1.292 djm 1343: error("channel %d: hostname \"%.100s\" too long",
1344: c->self, p);
1345: return -1;
1346: }
1.293 djm 1347: c->path = xstrdup(p);
1.403 djm 1348: if ((r = sshbuf_consume(input, len)) != 0)
1349: fatal_fr(r, "channel %d: consume", c->self);
1.292 djm 1350: }
1.103 markus 1351: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1352:
1.194 markus 1353: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1354: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1355:
1.104 markus 1356: if (s4_req.command != 1) {
1.292 djm 1357: debug("channel %d: cannot handle: %s cn %d",
1358: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1359: return -1;
1.103 markus 1360: }
1.104 markus 1361: s4_rsp.version = 0; /* vn: 0 for reply */
1362: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1363: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1364: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.403 djm 1365: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0)
1366: fatal_fr(r, "channel %d: append reply", c->self);
1.104 markus 1367: return 1;
1368: }
1369:
1.193 markus 1370: /* try to decode a socks5 header */
1371: #define SSH_SOCKS5_AUTHDONE 0x1000
1372: #define SSH_SOCKS5_NOAUTH 0x00
1373: #define SSH_SOCKS5_IPV4 0x01
1374: #define SSH_SOCKS5_DOMAIN 0x03
1375: #define SSH_SOCKS5_IPV6 0x04
1376: #define SSH_SOCKS5_CONNECT 0x01
1377: #define SSH_SOCKS5_SUCCESS 0x00
1378:
1379: static int
1.372 markus 1380: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1381: {
1.367 djm 1382: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1383: struct {
1384: u_int8_t version;
1385: u_int8_t command;
1386: u_int8_t reserved;
1387: u_int8_t atyp;
1388: } s5_req, s5_rsp;
1389: u_int16_t dest_port;
1.324 djm 1390: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1391: const u_char *p;
1.252 djm 1392: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1393: int r;
1.193 markus 1394:
1395: debug2("channel %d: decode socks5", c->self);
1.372 markus 1396: p = sshbuf_ptr(input);
1.193 markus 1397: if (p[0] != 0x05)
1398: return -1;
1.372 markus 1399: have = sshbuf_len(input);
1.193 markus 1400: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1401: /* format: ver | nmethods | methods */
1.198 djm 1402: if (have < 2)
1.193 markus 1403: return 0;
1404: nmethods = p[1];
1405: if (have < nmethods + 2)
1406: return 0;
1407: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1408: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1409: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1410: found = 1;
1411: break;
1412: }
1413: }
1414: if (!found) {
1415: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1416: c->self);
1417: return -1;
1418: }
1.403 djm 1419: if ((r = sshbuf_consume(input, nmethods + 2)) != 0)
1420: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1421: /* version, method */
1.372 markus 1422: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1.403 djm 1423: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0)
1424: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1425: c->flags |= SSH_SOCKS5_AUTHDONE;
1426: debug2("channel %d: socks5 auth done", c->self);
1427: return 0; /* need more */
1428: }
1429: debug2("channel %d: socks5 post auth", c->self);
1430: if (have < sizeof(s5_req)+1)
1431: return 0; /* need more */
1.247 deraadt 1432: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1433: if (s5_req.version != 0x05 ||
1434: s5_req.command != SSH_SOCKS5_CONNECT ||
1435: s5_req.reserved != 0x00) {
1.194 markus 1436: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1437: return -1;
1438: }
1.213 deraadt 1439: switch (s5_req.atyp){
1.193 markus 1440: case SSH_SOCKS5_IPV4:
1441: addrlen = 4;
1442: af = AF_INET;
1443: break;
1444: case SSH_SOCKS5_DOMAIN:
1445: addrlen = p[sizeof(s5_req)];
1446: af = -1;
1447: break;
1448: case SSH_SOCKS5_IPV6:
1449: addrlen = 16;
1450: af = AF_INET6;
1451: break;
1452: default:
1.194 markus 1453: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1454: return -1;
1455: }
1.252 djm 1456: need = sizeof(s5_req) + addrlen + 2;
1457: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1458: need++;
1459: if (have < need)
1.193 markus 1460: return 0;
1.403 djm 1461: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0)
1462: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1463: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1464: /* host string length */
1.403 djm 1465: if ((r = sshbuf_consume(input, 1)) != 0)
1466: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1467: }
1.372 markus 1468: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1469: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.403 djm 1470: debug_r(r, "channel %d: parse addr/port", c->self);
1.367 djm 1471: return -1;
1472: }
1.193 markus 1473: dest_addr[addrlen] = '\0';
1.321 djm 1474: free(c->path);
1475: c->path = NULL;
1.293 djm 1476: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1477: if (addrlen >= NI_MAXHOST) {
1.293 djm 1478: error("channel %d: dynamic request: socks5 hostname "
1479: "\"%.100s\" too long", c->self, dest_addr);
1480: return -1;
1481: }
1482: c->path = xstrdup(dest_addr);
1483: } else {
1484: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1485: return -1;
1486: c->path = xstrdup(ntop);
1487: }
1.193 markus 1488: c->host_port = ntohs(dest_port);
1.198 djm 1489:
1.194 markus 1490: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1491: c->self, c->path, c->host_port, s5_req.command);
1492:
1493: s5_rsp.version = 0x05;
1494: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1495: s5_rsp.reserved = 0; /* ignored */
1496: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1497: dest_port = 0; /* ignored */
1498:
1.372 markus 1499: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1500: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1501: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.403 djm 1502: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1503: return 1;
1.301 dtucker 1504: }
1505:
1506: Channel *
1.367 djm 1507: channel_connect_stdio_fwd(struct ssh *ssh,
1.407 djm 1508: const char *host_to_connect, u_short port_to_connect,
1509: int in, int out, int nonblock)
1.301 dtucker 1510: {
1511: Channel *c;
1512:
1.403 djm 1513: debug_f("%s:%d", host_to_connect, port_to_connect);
1.301 dtucker 1514:
1.367 djm 1515: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1516: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.407 djm 1517: 0, "stdio-forward", nonblock);
1.301 dtucker 1518:
1519: c->path = xstrdup(host_to_connect);
1520: c->host_port = port_to_connect;
1521: c->listening_port = 0;
1522: c->force_drain = 1;
1523:
1.367 djm 1524: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1525: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1526:
1527: return c;
1.193 markus 1528: }
1529:
1.104 markus 1530: /* dynamic port forwarding */
1.127 itojun 1531: static void
1.410 djm 1532: channel_pre_dynamic(struct ssh *ssh, Channel *c)
1.104 markus 1533: {
1.367 djm 1534: const u_char *p;
1.217 djm 1535: u_int have;
1536: int ret;
1.103 markus 1537:
1.410 djm 1538: c->io_want = 0;
1.367 djm 1539: have = sshbuf_len(c->input);
1.104 markus 1540: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1541: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1542: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1543: if (have < 3) {
1.104 markus 1544: /* need more */
1.410 djm 1545: c->io_want |= SSH_CHAN_IO_RFD;
1.104 markus 1546: return;
1547: }
1548: /* try to guess the protocol */
1.367 djm 1549: p = sshbuf_ptr(c->input);
1550: /* XXX sshbuf_peek_u8? */
1.104 markus 1551: switch (p[0]) {
1552: case 0x04:
1.372 markus 1553: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1554: break;
1555: case 0x05:
1.372 markus 1556: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1557: break;
1558: default:
1559: ret = -1;
1560: break;
1561: }
1562: if (ret < 0) {
1.367 djm 1563: chan_mark_dead(ssh, c);
1.104 markus 1564: } else if (ret == 0) {
1565: debug2("channel %d: pre_dynamic: need more", c->self);
1566: /* need more */
1.410 djm 1567: c->io_want |= SSH_CHAN_IO_RFD;
1.372 markus 1568: if (sshbuf_len(c->output))
1.410 djm 1569: c->io_want |= SSH_CHAN_IO_WFD;
1.104 markus 1570: } else {
1571: /* switch to the next state */
1572: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1573: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1574: }
1.103 markus 1575: }
1576:
1.372 markus 1577: /* simulate read-error */
1578: static void
1579: rdynamic_close(struct ssh *ssh, Channel *c)
1580: {
1581: c->type = SSH_CHANNEL_OPEN;
1582: chan_read_failed(ssh, c);
1583: sshbuf_reset(c->input);
1584: chan_ibuf_empty(ssh, c);
1585: sshbuf_reset(c->output);
1586: chan_write_failed(ssh, c);
1587: }
1588:
1589: /* reverse dynamic port forwarding */
1590: static void
1.411 djm 1591: channel_before_prepare_io_rdynamic(struct ssh *ssh, Channel *c)
1.372 markus 1592: {
1593: const u_char *p;
1594: u_int have, len;
1595: int r, ret;
1596:
1597: have = sshbuf_len(c->output);
1598: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1599: /* sshbuf_dump(c->output, stderr); */
1600: /* EOF received */
1601: if (c->flags & CHAN_EOF_RCVD) {
1.403 djm 1602: if ((r = sshbuf_consume(c->output, have)) != 0)
1603: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1604: rdynamic_close(ssh, c);
1605: return;
1606: }
1607: /* check if the fixed size part of the packet is in buffer. */
1608: if (have < 3)
1609: return;
1610: /* try to guess the protocol */
1611: p = sshbuf_ptr(c->output);
1612: switch (p[0]) {
1613: case 0x04:
1614: /* switch input/output for reverse forwarding */
1615: ret = channel_decode_socks4(c, c->output, c->input);
1616: break;
1617: case 0x05:
1618: ret = channel_decode_socks5(c, c->output, c->input);
1619: break;
1620: default:
1621: ret = -1;
1622: break;
1623: }
1624: if (ret < 0) {
1625: rdynamic_close(ssh, c);
1626: } else if (ret == 0) {
1627: debug2("channel %d: pre_rdynamic: need more", c->self);
1628: /* send socks request to peer */
1629: len = sshbuf_len(c->input);
1630: if (len > 0 && len < c->remote_window) {
1631: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1632: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1633: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1634: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 1635: fatal_fr(r, "channel %i: rdynamic", c->self);
1.372 markus 1636: }
1.403 djm 1637: if ((r = sshbuf_consume(c->input, len)) != 0)
1638: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1639: c->remote_window -= len;
1640: }
1641: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1642: /* the connect failed */
1643: rdynamic_close(ssh, c);
1644: }
1645: }
1646:
1.41 markus 1647: /* This is our fake X11 server socket. */
1.127 itojun 1648: static void
1.410 djm 1649: channel_post_x11_listener(struct ssh *ssh, Channel *c)
1.41 markus 1650: {
1.113 markus 1651: Channel *nc;
1.285 djm 1652: struct sockaddr_storage addr;
1.367 djm 1653: int r, newsock, oerrno, remote_port;
1.41 markus 1654: socklen_t addrlen;
1.85 markus 1655: char buf[16384], *remote_ipaddr;
1.25 markus 1656:
1.410 djm 1657: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1658: return;
1659:
1660: debug("X11 connection requested.");
1661: addrlen = sizeof(addr);
1662: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1663: if (c->single_connection) {
1664: oerrno = errno;
1665: debug2("single_connection: closing X11 listener.");
1.407 djm 1666: channel_close_fd(ssh, c, &c->sock);
1.367 djm 1667: chan_mark_dead(ssh, c);
1668: errno = oerrno;
1669: }
1.393 deraadt 1670: if (newsock == -1) {
1.367 djm 1671: if (errno != EINTR && errno != EWOULDBLOCK &&
1672: errno != ECONNABORTED)
1673: error("accept: %.100s", strerror(errno));
1674: if (errno == EMFILE || errno == ENFILE)
1675: c->notbefore = monotime() + 1;
1676: return;
1677: }
1678: set_nodelay(newsock);
1679: remote_ipaddr = get_peer_ipaddr(newsock);
1680: remote_port = get_peer_port(newsock);
1681: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1682: remote_ipaddr, remote_port);
1683:
1684: nc = channel_new(ssh, "accepted x11 socket",
1685: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1686: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1687: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1688: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1689: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.403 djm 1690: fatal_fr(r, "channel %i: reply", c->self);
1.41 markus 1691: }
1.367 djm 1692: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1693: fatal_fr(r, "channel %i: send", c->self);
1.367 djm 1694: free(remote_ipaddr);
1.41 markus 1695: }
1.25 markus 1696:
1.127 itojun 1697: static void
1.367 djm 1698: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1699: {
1.328 djm 1700: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1701: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1702: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1703: int remote_port = get_peer_port(c->sock);
1.367 djm 1704: int r;
1.303 djm 1705:
1706: if (remote_port == -1) {
1707: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1708: free(remote_ipaddr);
1.303 djm 1709: remote_ipaddr = xstrdup("127.0.0.1");
1710: remote_port = 65535;
1711: }
1.103 markus 1712:
1.367 djm 1713: free(c->remote_name);
1714: xasprintf(&c->remote_name,
1.103 markus 1715: "%s: listening port %d for %.100s port %d, "
1.328 djm 1716: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1717: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1718: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1719:
1.367 djm 1720: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1721: if (strcmp(rtype, "direct-tcpip") == 0) {
1722: /* target host, port */
1.367 djm 1723: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1724: (r = sshpkt_put_u32(ssh, c->host_port)) != 0)
1725: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1726: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1727: /* target path */
1.403 djm 1728: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1729: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1730: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1731: /* listen path */
1.403 djm 1732: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1733: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1734: } else {
1.358 djm 1735: /* listen address, port */
1.367 djm 1736: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1737: (r = sshpkt_put_u32(ssh, local_port)) != 0)
1738: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1739: }
1740: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1741: /* reserved for future owner/mode info */
1.403 djm 1742: if ((r = sshpkt_put_cstring(ssh, "")) != 0)
1743: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1744: } else {
1745: /* originator host and port */
1.367 djm 1746: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1.403 djm 1747: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0)
1748: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1749: }
1.367 djm 1750: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1751: fatal_fr(r, "channel %i: send", c->self);
1.321 djm 1752: free(remote_ipaddr);
1.328 djm 1753: free(local_ipaddr);
1.103 markus 1754: }
1755:
1.347 djm 1756: void
1.367 djm 1757: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1758: {
1.367 djm 1759: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1760: }
1761:
1.41 markus 1762: /*
1763: * This socket is listening for connections to a forwarded TCP/IP port.
1764: */
1.127 itojun 1765: static void
1.410 djm 1766: channel_post_port_listener(struct ssh *ssh, Channel *c)
1.41 markus 1767: {
1.103 markus 1768: Channel *nc;
1.285 djm 1769: struct sockaddr_storage addr;
1.113 markus 1770: int newsock, nextstate;
1.41 markus 1771: socklen_t addrlen;
1.103 markus 1772: char *rtype;
1.73 markus 1773:
1.410 djm 1774: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1775: return;
1776:
1777: debug("Connection to port %d forwarding to %.100s port %d requested.",
1778: c->listening_port, c->path, c->host_port);
1.103 markus 1779:
1.367 djm 1780: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1781: nextstate = SSH_CHANNEL_OPENING;
1782: rtype = "forwarded-tcpip";
1783: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1784: nextstate = SSH_CHANNEL_OPENING;
1785: rtype = "forwarded-streamlocal@openssh.com";
1786: } else if (c->host_port == PORT_STREAMLOCAL) {
1787: nextstate = SSH_CHANNEL_OPENING;
1788: rtype = "direct-streamlocal@openssh.com";
1789: } else if (c->host_port == 0) {
1790: nextstate = SSH_CHANNEL_DYNAMIC;
1791: rtype = "dynamic-tcpip";
1792: } else {
1793: nextstate = SSH_CHANNEL_OPENING;
1794: rtype = "direct-tcpip";
1795: }
1.103 markus 1796:
1.367 djm 1797: addrlen = sizeof(addr);
1798: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1799: if (newsock == -1) {
1.367 djm 1800: if (errno != EINTR && errno != EWOULDBLOCK &&
1801: errno != ECONNABORTED)
1802: error("accept: %.100s", strerror(errno));
1803: if (errno == EMFILE || errno == ENFILE)
1804: c->notbefore = monotime() + 1;
1805: return;
1.41 markus 1806: }
1.367 djm 1807: if (c->host_port != PORT_STREAMLOCAL)
1808: set_nodelay(newsock);
1809: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1810: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1811: nc->listening_port = c->listening_port;
1812: nc->host_port = c->host_port;
1813: if (c->path != NULL)
1814: nc->path = xstrdup(c->path);
1815:
1816: if (nextstate != SSH_CHANNEL_DYNAMIC)
1817: port_open_helper(ssh, nc, rtype);
1.41 markus 1818: }
1.25 markus 1819:
1.41 markus 1820: /*
1821: * This is the authentication agent socket listening for connections from
1822: * clients.
1823: */
1.127 itojun 1824: static void
1.410 djm 1825: channel_post_auth_listener(struct ssh *ssh, Channel *c)
1.41 markus 1826: {
1.113 markus 1827: Channel *nc;
1.367 djm 1828: int r, newsock;
1.285 djm 1829: struct sockaddr_storage addr;
1.41 markus 1830: socklen_t addrlen;
1.25 markus 1831:
1.410 djm 1832: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1833: return;
1834:
1835: addrlen = sizeof(addr);
1836: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1837: if (newsock == -1) {
1.367 djm 1838: error("accept from auth socket: %.100s", strerror(errno));
1839: if (errno == EMFILE || errno == ENFILE)
1840: c->notbefore = monotime() + 1;
1841: return;
1.41 markus 1842: }
1.367 djm 1843: nc = channel_new(ssh, "accepted auth socket",
1844: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1845: c->local_window_max, c->local_maxpacket,
1846: 0, "accepted auth socket", 1);
1847: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1848: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1849: fatal_fr(r, "channel %i", c->self);
1.41 markus 1850: }
1.25 markus 1851:
1.127 itojun 1852: static void
1.410 djm 1853: channel_post_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1854: {
1.372 markus 1855: int err = 0, sock, isopen, r;
1.129 stevesk 1856: socklen_t sz = sizeof(err);
1.114 markus 1857:
1.410 djm 1858: if ((c->io_ready & SSH_CHAN_IO_SOCK_W) == 0)
1.367 djm 1859: return;
1.368 djm 1860: if (!c->have_remote_id)
1.403 djm 1861: fatal_f("channel %d: no remote id", c->self);
1.372 markus 1862: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1863: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.393 deraadt 1864: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 1865: err = errno;
1866: error("getsockopt SO_ERROR failed");
1867: }
1868: if (err == 0) {
1869: debug("channel %d: connected to %s port %d",
1870: c->self, c->connect_ctx.host, c->connect_ctx.port);
1871: channel_connect_ctx_free(&c->connect_ctx);
1872: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1873: if (isopen) {
1874: /* no message necessary */
1875: } else {
1876: if ((r = sshpkt_start(ssh,
1877: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1878: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1879: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1880: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 1881: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0 ||
1882: (r = sshpkt_send(ssh)) != 0)
1883: fatal_fr(r, "channel %i open confirm", c->self);
1.367 djm 1884: }
1885: } else {
1886: debug("channel %d: connection failed: %s",
1887: c->self, strerror(err));
1888: /* Try next address, if any */
1889: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1890: close(c->sock);
1891: c->sock = c->rfd = c->wfd = sock;
1892: return;
1893: }
1894: /* Exhausted all addresses */
1895: error("connect_to %.100s port %d: failed.",
1896: c->connect_ctx.host, c->connect_ctx.port);
1897: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1898: if (isopen) {
1899: rdynamic_close(ssh, c);
1900: } else {
1901: if ((r = sshpkt_start(ssh,
1902: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1903: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 1904: (r = sshpkt_put_u32(ssh,
1905: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
1906: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1.403 djm 1907: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1908: (r = sshpkt_send(ssh)) != 0)
1909: fatal_fr(r, "channel %i: failure", c->self);
1.372 markus 1910: chan_mark_dead(ssh, c);
1.75 markus 1911: }
1912: }
1913: }
1914:
1.127 itojun 1915: static int
1.410 djm 1916: channel_handle_rfd(struct ssh *ssh, Channel *c)
1.41 markus 1917: {
1.214 markus 1918: char buf[CHAN_RBUF];
1.367 djm 1919: ssize_t len;
1920: int r;
1.412 djm 1921: size_t have, avail, maxlen = CHANNEL_MAX_READ;
1.25 markus 1922:
1.410 djm 1923: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.412 djm 1924: return 1; /* Shouldn't happen */
1925: if ((avail = sshbuf_avail(c->input)) == 0)
1926: return 1; /* Shouldn't happen */
1927:
1928: /*
1929: * For "simple" channels (i.e. not datagram or filtered), we can
1930: * read directly to the channel buffer.
1931: */
1932: if (c->input_filter == NULL && !c->datagram) {
1933: /* Only OPEN channels have valid rwin */
1934: if (c->type == SSH_CHANNEL_OPEN) {
1935: if ((have = sshbuf_len(c->input)) >= c->remote_window)
1936: return 1; /* shouldn't happen */
1937: if (maxlen > c->remote_window - have)
1938: maxlen = c->remote_window - have;
1939: }
1940: if (maxlen > avail)
1941: maxlen = avail;
1942: if ((r = sshbuf_read(c->rfd, c->input, maxlen, NULL)) != 0) {
1.413 djm 1943: if (errno == EINTR || errno == EAGAIN)
1944: return 1;
1.412 djm 1945: debug2("channel %d: read failed rfd %d maxlen %zu: %s",
1946: c->self, c->rfd, maxlen, ssh_err(r));
1947: goto rfail;
1948: }
1.367 djm 1949: return 1;
1.412 djm 1950: }
1.367 djm 1951:
1952: len = read(c->rfd, buf, sizeof(buf));
1.393 deraadt 1953: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 1954: return 1;
1955: if (len <= 0) {
1.412 djm 1956: debug2("channel %d: read<=0 rfd %d len %zd: %s",
1957: c->self, c->rfd, len,
1958: len == 0 ? "closed" : strerror(errno));
1959: rfail:
1.367 djm 1960: if (c->type != SSH_CHANNEL_OPEN) {
1961: debug2("channel %d: not open", c->self);
1962: chan_mark_dead(ssh, c);
1.41 markus 1963: return -1;
1.65 markus 1964: } else {
1.367 djm 1965: chan_read_failed(ssh, c);
1.65 markus 1966: }
1.367 djm 1967: return -1;
1968: }
1969: if (c->input_filter != NULL) {
1970: if (c->input_filter(ssh, c, buf, len) == -1) {
1971: debug2("channel %d: filter stops", c->self);
1972: chan_read_failed(ssh, c);
1973: }
1974: } else if (c->datagram) {
1975: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1.403 djm 1976: fatal_fr(r, "channel %i: put datagram", c->self);
1.412 djm 1977: }
1.41 markus 1978: return 1;
1979: }
1.241 deraadt 1980:
1.127 itojun 1981: static int
1.410 djm 1982: channel_handle_wfd(struct ssh *ssh, Channel *c)
1.41 markus 1983: {
1.95 markus 1984: struct termios tio;
1.367 djm 1985: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1986: size_t dlen, olen = 0;
1987: int r, len;
1988:
1.410 djm 1989: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
1990: return 1;
1991: if (sshbuf_len(c->output) == 0)
1.367 djm 1992: return 1;
1.25 markus 1993:
1.41 markus 1994: /* Send buffered output data to the socket. */
1.367 djm 1995: olen = sshbuf_len(c->output);
1996: if (c->output_filter != NULL) {
1997: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1998: debug2("channel %d: filter stops", c->self);
1999: if (c->type != SSH_CHANNEL_OPEN)
2000: chan_mark_dead(ssh, c);
2001: else
2002: chan_write_failed(ssh, c);
2003: return -1;
1.231 reyk 2004: }
1.367 djm 2005: } else if (c->datagram) {
2006: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1.403 djm 2007: fatal_fr(r, "channel %i: get datagram", c->self);
1.369 djm 2008: buf = data;
1.367 djm 2009: } else {
2010: buf = data = sshbuf_mutable_ptr(c->output);
2011: dlen = sshbuf_len(c->output);
2012: }
1.231 reyk 2013:
1.367 djm 2014: if (c->datagram) {
2015: /* ignore truncated writes, datagrams might get lost */
1.374 djm 2016: len = write(c->wfd, buf, dlen);
1.367 djm 2017: free(data);
1.393 deraadt 2018: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 2019: return 1;
1.367 djm 2020: if (len <= 0)
2021: goto write_fail;
2022: goto out;
2023: }
2024:
2025: len = write(c->wfd, buf, dlen);
1.393 deraadt 2026: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2027: return 1;
2028: if (len <= 0) {
2029: write_fail:
2030: if (c->type != SSH_CHANNEL_OPEN) {
2031: debug2("channel %d: not open", c->self);
2032: chan_mark_dead(ssh, c);
1.41 markus 2033: return -1;
1.367 djm 2034: } else {
2035: chan_write_failed(ssh, c);
1.91 markus 2036: }
1.367 djm 2037: return -1;
2038: }
2039: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2040: if (tcgetattr(c->wfd, &tio) == 0 &&
2041: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2042: /*
2043: * Simulate echo to reduce the impact of
2044: * traffic analysis. We need to match the
2045: * size of a SSH2_MSG_CHANNEL_DATA message
2046: * (4 byte channel id + buf)
2047: */
2048: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2049: (r = sshpkt_send(ssh)) != 0)
1.403 djm 2050: fatal_fr(r, "channel %i: ignore", c->self);
1.25 markus 2051: }
1.367 djm 2052: }
1.403 djm 2053: if ((r = sshbuf_consume(c->output, len)) != 0)
2054: fatal_fr(r, "channel %i: consume", c->self);
1.309 djm 2055: out:
1.367 djm 2056: c->local_consumed += olen - sshbuf_len(c->output);
2057:
2058: return 1;
2059: }
2060:
2061: static int
1.410 djm 2062: channel_handle_efd_write(struct ssh *ssh, Channel *c)
1.367 djm 2063: {
2064: int r;
2065: ssize_t len;
2066:
1.410 djm 2067: if ((c->io_ready & SSH_CHAN_IO_EFD_W) == 0)
2068: return 1;
2069: if (sshbuf_len(c->extended) == 0)
1.367 djm 2070: return 1;
2071:
2072: len = write(c->efd, sshbuf_ptr(c->extended),
2073: sshbuf_len(c->extended));
2074: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 deraadt 2075: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2076: return 1;
2077: if (len <= 0) {
2078: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1.407 djm 2079: channel_close_fd(ssh, c, &c->efd);
1.367 djm 2080: } else {
1.403 djm 2081: if ((r = sshbuf_consume(c->extended, len)) != 0)
2082: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2083: c->local_consumed += len;
2084: }
1.44 markus 2085: return 1;
2086: }
1.241 deraadt 2087:
1.127 itojun 2088: static int
1.410 djm 2089: channel_handle_efd_read(struct ssh *ssh, Channel *c)
1.44 markus 2090: {
1.214 markus 2091: char buf[CHAN_RBUF];
1.367 djm 2092: int r;
2093: ssize_t len;
2094:
1.410 djm 2095: if ((c->io_ready & SSH_CHAN_IO_EFD_R) == 0)
1.367 djm 2096: return 1;
1.44 markus 2097:
1.367 djm 2098: len = read(c->efd, buf, sizeof(buf));
2099: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 deraadt 2100: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2101: return 1;
2102: if (len <= 0) {
1.403 djm 2103: debug2("channel %d: closing read-efd %d", c->self, c->efd);
1.407 djm 2104: channel_close_fd(ssh, c, &c->efd);
1.403 djm 2105: } else if (c->extended_usage == CHAN_EXTENDED_IGNORE)
2106: debug3("channel %d: discard efd", c->self);
2107: else if ((r = sshbuf_put(c->extended, buf, len)) != 0)
2108: fatal_fr(r, "channel %i: append", c->self);
1.44 markus 2109: return 1;
2110: }
1.241 deraadt 2111:
1.127 itojun 2112: static int
1.410 djm 2113: channel_handle_efd(struct ssh *ssh, Channel *c)
1.44 markus 2114: {
1.367 djm 2115: if (c->efd == -1)
2116: return 1;
2117:
2118: /** XXX handle drain efd, too */
2119:
2120: if (c->extended_usage == CHAN_EXTENDED_WRITE)
1.410 djm 2121: return channel_handle_efd_write(ssh, c);
1.367 djm 2122: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2123: c->extended_usage == CHAN_EXTENDED_IGNORE)
1.410 djm 2124: return channel_handle_efd_read(ssh, c);
1.367 djm 2125:
2126: return 1;
2127: }
2128:
2129: static int
2130: channel_check_window(struct ssh *ssh, Channel *c)
2131: {
2132: int r;
2133:
1.104 markus 2134: if (c->type == SSH_CHANNEL_OPEN &&
2135: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2136: ((c->local_window_max - c->local_window >
1.269 markus 2137: c->local_maxpacket*3) ||
2138: c->local_window < c->local_window_max/2) &&
1.44 markus 2139: c->local_consumed > 0) {
1.368 djm 2140: if (!c->have_remote_id)
1.403 djm 2141: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2142: if ((r = sshpkt_start(ssh,
2143: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2144: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2145: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2146: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2147: fatal_fr(r, "channel %i", c->self);
1.367 djm 2148: }
1.403 djm 2149: debug2("channel %d: window %d sent adjust %d", c->self,
2150: c->local_window, c->local_consumed);
1.44 markus 2151: c->local_window += c->local_consumed;
2152: c->local_consumed = 0;
1.1 deraadt 2153: }
1.41 markus 2154: return 1;
1.1 deraadt 2155: }
2156:
1.127 itojun 2157: static void
1.410 djm 2158: channel_post_open(struct ssh *ssh, Channel *c)
1.41 markus 2159: {
1.410 djm 2160: channel_handle_rfd(ssh, c);
2161: channel_handle_wfd(ssh, c);
2162: channel_handle_efd(ssh, c);
1.367 djm 2163: channel_check_window(ssh, c);
1.44 markus 2164: }
2165:
1.302 djm 2166: static u_int
1.367 djm 2167: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2168: {
2169: char buf[CHAN_RBUF];
1.367 djm 2170: ssize_t len;
1.302 djm 2171: u_int rlen;
1.367 djm 2172: int r;
1.302 djm 2173:
1.367 djm 2174: if (sshbuf_len(c->input) < need) {
2175: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2176: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 deraadt 2177: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2178: return sshbuf_len(c->input);
1.302 djm 2179: if (len <= 0) {
1.367 djm 2180: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2181: c->self, c->rfd, len);
1.367 djm 2182: chan_read_failed(ssh, c);
1.349 naddy 2183: return 0;
1.403 djm 2184: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
2185: fatal_fr(r, "channel %i: append", c->self);
1.302 djm 2186: }
1.367 djm 2187: return sshbuf_len(c->input);
1.302 djm 2188: }
2189:
2190: static void
1.410 djm 2191: channel_post_mux_client_read(struct ssh *ssh, Channel *c)
1.302 djm 2192: {
2193: u_int need;
2194:
1.410 djm 2195: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.367 djm 2196: return;
2197: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2198: return;
2199: if (c->mux_pause)
2200: return;
2201:
2202: /*
2203: * Don't not read past the precise end of packets to
2204: * avoid disrupting fd passing.
2205: */
2206: if (read_mux(ssh, c, 4) < 4) /* read header */
2207: return;
2208: /* XXX sshbuf_peek_u32 */
2209: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2210: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2211: if (need > CHANNEL_MUX_MAX_PACKET) {
2212: debug2("channel %d: packet too big %u > %u",
2213: c->self, CHANNEL_MUX_MAX_PACKET, need);
2214: chan_rcvd_oclose(ssh, c);
2215: return;
2216: }
2217: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2218: return;
2219: if (c->mux_rcb(ssh, c) != 0) {
2220: debug("channel %d: mux_rcb failed", c->self);
2221: chan_mark_dead(ssh, c);
2222: return;
1.302 djm 2223: }
1.367 djm 2224: }
2225:
2226: static void
1.410 djm 2227: channel_post_mux_client_write(struct ssh *ssh, Channel *c)
1.367 djm 2228: {
2229: ssize_t len;
2230: int r;
1.302 djm 2231:
1.410 djm 2232: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
2233: return;
2234: if (sshbuf_len(c->output) == 0)
1.367 djm 2235: return;
2236:
2237: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 deraadt 2238: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2239: return;
2240: if (len <= 0) {
2241: chan_mark_dead(ssh, c);
2242: return;
1.302 djm 2243: }
1.367 djm 2244: if ((r = sshbuf_consume(c->output, len)) != 0)
1.403 djm 2245: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2246: }
2247:
2248: static void
1.410 djm 2249: channel_post_mux_client(struct ssh *ssh, Channel *c)
1.367 djm 2250: {
1.410 djm 2251: channel_post_mux_client_read(ssh, c);
2252: channel_post_mux_client_write(ssh, c);
1.302 djm 2253: }
2254:
2255: static void
1.410 djm 2256: channel_post_mux_listener(struct ssh *ssh, Channel *c)
1.302 djm 2257: {
2258: Channel *nc;
2259: struct sockaddr_storage addr;
2260: socklen_t addrlen;
2261: int newsock;
2262: uid_t euid;
2263: gid_t egid;
2264:
1.410 djm 2265: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.302 djm 2266: return;
2267:
2268: debug("multiplexing control connection");
2269:
2270: /*
2271: * Accept connection on control socket
2272: */
2273: memset(&addr, 0, sizeof(addr));
2274: addrlen = sizeof(addr);
2275: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2276: &addrlen)) == -1) {
1.403 djm 2277: error_f("accept: %s", strerror(errno));
1.317 djm 2278: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2279: c->notbefore = monotime() + 1;
1.302 djm 2280: return;
2281: }
2282:
1.393 deraadt 2283: if (getpeereid(newsock, &euid, &egid) == -1) {
1.403 djm 2284: error_f("getpeereid failed: %s", strerror(errno));
1.302 djm 2285: close(newsock);
2286: return;
2287: }
2288: if ((euid != 0) && (getuid() != euid)) {
2289: error("multiplex uid mismatch: peer euid %u != uid %u",
2290: (u_int)euid, (u_int)getuid());
2291: close(newsock);
2292: return;
2293: }
1.367 djm 2294: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2295: newsock, newsock, -1, c->local_window_max,
2296: c->local_maxpacket, 0, "mux-control", 1);
2297: nc->mux_rcb = c->mux_rcb;
1.403 djm 2298: debug3_f("new mux channel %d fd %d", nc->self, nc->sock);
1.302 djm 2299: /* establish state */
1.367 djm 2300: nc->mux_rcb(ssh, nc);
1.302 djm 2301: /* mux state transitions must not elicit protocol messages */
2302: nc->flags |= CHAN_LOCAL;
2303: }
2304:
1.127 itojun 2305: static void
1.367 djm 2306: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2307: {
1.367 djm 2308: chan_fn **pre, **post;
2309:
2310: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
1.406 djm 2311: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
1.403 djm 2312: fatal_f("allocation failed");
1.367 djm 2313:
2314: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2315: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2316: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2317: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2318: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2319: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2320: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2321: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2322: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2323: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2324: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2325: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2326: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2327:
2328: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2329: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2330: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2331: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2332: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2333: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2334: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2335: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2336: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2337: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2338: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2339: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2340:
1.367 djm 2341: sc->channel_pre = pre;
2342: sc->channel_post = post;
1.44 markus 2343: }
2344:
1.140 markus 2345: /* gc dead channels */
2346: static void
1.367 djm 2347: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2348: {
2349: if (c == NULL)
2350: return;
2351: if (c->detach_user != NULL) {
1.367 djm 2352: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2353: return;
1.385 djm 2354:
1.194 markus 2355: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2356: c->detach_user(ssh, c->self, NULL);
1.140 markus 2357: /* if we still have a callback */
2358: if (c->detach_user != NULL)
2359: return;
1.194 markus 2360: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2361: }
1.367 djm 2362: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2363: return;
1.194 markus 2364: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2365: channel_free(ssh, c);
1.140 markus 2366: }
2367:
1.367 djm 2368: enum channel_table { CHAN_PRE, CHAN_POST };
2369:
1.127 itojun 2370: static void
1.410 djm 2371: channel_handler(struct ssh *ssh, int table, time_t *unpause_secs)
1.41 markus 2372: {
1.367 djm 2373: struct ssh_channels *sc = ssh->chanctxt;
2374: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2375: u_int i, oalloc;
1.41 markus 2376: Channel *c;
1.317 djm 2377: time_t now;
1.25 markus 2378:
1.322 dtucker 2379: now = monotime();
1.317 djm 2380: if (unpause_secs != NULL)
2381: *unpause_secs = 0;
1.367 djm 2382: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2383: c = sc->channels[i];
1.113 markus 2384: if (c == NULL)
1.41 markus 2385: continue;
1.417 djm 2386: /* Try to keep IO going while rekeying */
2387: if (ssh_packet_is_rekeying(ssh) && c->type != SSH_CHANNEL_OPEN)
2388: continue;
1.299 markus 2389: if (c->delayed) {
1.367 djm 2390: if (table == CHAN_PRE)
1.299 markus 2391: c->delayed = 0;
2392: else
2393: continue;
2394: }
1.317 djm 2395: if (ftab[c->type] != NULL) {
2396: /*
2397: * Run handlers that are not paused.
2398: */
2399: if (c->notbefore <= now)
1.410 djm 2400: (*ftab[c->type])(ssh, c);
1.317 djm 2401: else if (unpause_secs != NULL) {
2402: /*
2403: * Collect the time that the earliest
2404: * channel comes off pause.
2405: */
1.403 djm 2406: debug3_f("chan %d: skip for %d more "
2407: "seconds", c->self,
1.317 djm 2408: (int)(c->notbefore - now));
2409: if (*unpause_secs == 0 ||
2410: (c->notbefore - now) < *unpause_secs)
2411: *unpause_secs = c->notbefore - now;
2412: }
2413: }
1.367 djm 2414: channel_garbage_collect(ssh, c);
1.1 deraadt 2415: }
1.317 djm 2416: if (unpause_secs != NULL && *unpause_secs != 0)
1.403 djm 2417: debug3_f("first channel unpauses in %d seconds",
2418: (int)*unpause_secs);
1.1 deraadt 2419: }
2420:
1.121 markus 2421: /*
1.411 djm 2422: * Create sockets before preparing IO.
1.372 markus 2423: * This is necessary for things that need to happen after reading
1.411 djm 2424: * the network-input but need to be completed before IO event setup, e.g.
2425: * because they may create new channels.
1.372 markus 2426: */
2427: static void
1.411 djm 2428: channel_before_prepare_io(struct ssh *ssh)
1.372 markus 2429: {
2430: struct ssh_channels *sc = ssh->chanctxt;
2431: Channel *c;
2432: u_int i, oalloc;
2433:
2434: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2435: c = sc->channels[i];
2436: if (c == NULL)
2437: continue;
2438: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
1.411 djm 2439: channel_before_prepare_io_rdynamic(ssh, c);
2440: }
2441: }
2442:
2443: static void
2444: dump_channel_poll(const char *func, const char *what, Channel *c,
2445: u_int pollfd_offset, struct pollfd *pfd)
2446: {
2447: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2448: debug3("%s: channel %d: %s r%d w%d e%d s%d c->pfds [ %d %d %d %d ] "
2449: "io_want 0x%02x io_ready 0x%02x pfd[%u].fd=%d "
2450: "pfd.ev 0x%02x pfd.rev 0x%02x", func, c->self, what,
2451: c->rfd, c->wfd, c->efd, c->sock,
2452: c->pfds[0], c->pfds[1], c->pfds[2], c->pfds[3],
2453: c->io_want, c->io_ready,
2454: pollfd_offset, pfd->fd, pfd->events, pfd->revents);
1.411 djm 2455: #endif
2456: }
2457:
2458: /* Prepare pollfd entries for a single channel */
2459: static void
2460: channel_prepare_pollfd(Channel *c, u_int *next_pollfd,
2461: struct pollfd *pfd, u_int npfd)
2462: {
1.415 djm 2463: u_int ev, p = *next_pollfd;
1.411 djm 2464:
2465: if (c == NULL)
2466: return;
2467: if (p + 4 > npfd) {
2468: /* Shouldn't happen */
2469: fatal_f("channel %d: bad pfd offset %u (max %u)",
2470: c->self, p, npfd);
2471: }
1.415 djm 2472: c->pfds[0] = c->pfds[1] = c->pfds[2] = c->pfds[3] = -1;
1.411 djm 2473: /*
2474: * prepare c->rfd
2475: *
2476: * This is a special case, since c->rfd might be the same as
2477: * c->wfd, c->efd and/or c->sock. Handle those here if they want
2478: * IO too.
2479: */
2480: if (c->rfd != -1) {
1.415 djm 2481: ev = 0;
1.411 djm 2482: if ((c->io_want & SSH_CHAN_IO_RFD) != 0)
1.415 djm 2483: ev |= POLLIN;
1.411 djm 2484: /* rfd == wfd */
1.415 djm 2485: if (c->wfd == c->rfd) {
2486: if ((c->io_want & SSH_CHAN_IO_WFD) != 0)
2487: ev |= POLLOUT;
2488: }
1.411 djm 2489: /* rfd == efd */
1.415 djm 2490: if (c->efd == c->rfd) {
2491: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
2492: ev |= POLLIN;
2493: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
2494: ev |= POLLOUT;
2495: }
1.411 djm 2496: /* rfd == sock */
1.415 djm 2497: if (c->sock == c->rfd) {
2498: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
2499: ev |= POLLIN;
2500: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
2501: ev |= POLLOUT;
2502: }
2503: /* Pack a pfd entry if any event armed for this fd */
2504: if (ev != 0) {
2505: c->pfds[0] = p;
2506: pfd[p].fd = c->rfd;
2507: pfd[p].events = ev;
2508: dump_channel_poll(__func__, "rfd", c, p, &pfd[p]);
2509: p++;
2510: }
1.411 djm 2511: }
1.415 djm 2512: /* prepare c->wfd if wanting IO and not already handled above */
1.411 djm 2513: if (c->wfd != -1 && c->rfd != c->wfd) {
1.415 djm 2514: ev = 0;
2515: if ((c->io_want & SSH_CHAN_IO_WFD))
2516: ev |= POLLOUT;
2517: /* Pack a pfd entry if any event armed for this fd */
2518: if (ev != 0) {
2519: c->pfds[1] = p;
2520: pfd[p].fd = c->wfd;
2521: pfd[p].events = ev;
2522: dump_channel_poll(__func__, "wfd", c, p, &pfd[p]);
2523: p++;
2524: }
1.411 djm 2525: }
1.415 djm 2526: /* prepare c->efd if wanting IO and not already handled above */
1.411 djm 2527: if (c->efd != -1 && c->rfd != c->efd) {
1.415 djm 2528: ev = 0;
1.411 djm 2529: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
1.415 djm 2530: ev |= POLLIN;
1.411 djm 2531: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
1.415 djm 2532: ev |= POLLOUT;
2533: /* Pack a pfd entry if any event armed for this fd */
2534: if (ev != 0) {
2535: c->pfds[2] = p;
2536: pfd[p].fd = c->efd;
2537: pfd[p].events = ev;
2538: dump_channel_poll(__func__, "efd", c, p, &pfd[p]);
2539: p++;
2540: }
1.411 djm 2541: }
1.415 djm 2542: /* prepare c->sock if wanting IO and not already handled above */
1.411 djm 2543: if (c->sock != -1 && c->rfd != c->sock) {
1.415 djm 2544: ev = 0;
1.411 djm 2545: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
1.415 djm 2546: ev |= POLLIN;
1.411 djm 2547: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
1.415 djm 2548: ev |= POLLOUT;
2549: /* Pack a pfd entry if any event armed for this fd */
2550: if (ev != 0) {
2551: c->pfds[3] = p;
2552: pfd[p].fd = c->sock;
2553: pfd[p].events = 0;
2554: dump_channel_poll(__func__, "sock", c, p, &pfd[p]);
2555: p++;
2556: }
1.372 markus 2557: }
1.411 djm 2558: *next_pollfd = p;
1.372 markus 2559: }
2560:
1.411 djm 2561: /* * Allocate/prepare poll structure */
1.49 markus 2562: void
1.411 djm 2563: channel_prepare_poll(struct ssh *ssh, struct pollfd **pfdp, u_int *npfd_allocp,
2564: u_int *npfd_activep, u_int npfd_reserved, time_t *minwait_secs)
1.41 markus 2565: {
1.410 djm 2566: struct ssh_channels *sc = ssh->chanctxt;
1.411 djm 2567: u_int i, oalloc, p, npfd = npfd_reserved;
2568:
2569: channel_before_prepare_io(ssh); /* might create a new channel */
1.416 djm 2570: /* clear out I/O flags from last poll */
2571: for (i = 0; i < sc->channels_alloc; i++) {
2572: if (sc->channels[i] == NULL)
2573: continue;
2574: sc->channels[i]->io_want = sc->channels[i]->io_ready = 0;
2575: }
1.411 djm 2576: /* Allocate 4x pollfd for each channel (rfd, wfd, efd, sock) */
2577: if (sc->channels_alloc >= (INT_MAX / 4) - npfd_reserved)
2578: fatal_f("too many channels"); /* shouldn't happen */
1.417 djm 2579: npfd += sc->channels_alloc * 4;
1.411 djm 2580: if (npfd > *npfd_allocp) {
2581: *pfdp = xrecallocarray(*pfdp, *npfd_allocp,
2582: npfd, sizeof(**pfdp));
2583: *npfd_allocp = npfd;
2584: }
2585: *npfd_activep = npfd_reserved;
2586: oalloc = sc->channels_alloc;
1.372 markus 2587:
1.411 djm 2588: channel_handler(ssh, CHAN_PRE, minwait_secs);
1.84 markus 2589:
1.411 djm 2590: if (oalloc != sc->channels_alloc) {
2591: /* shouldn't happen */
2592: fatal_f("channels_alloc changed during CHAN_PRE "
2593: "(was %u, now %u)", oalloc, sc->channels_alloc);
2594: }
1.84 markus 2595:
1.411 djm 2596: /* Prepare pollfd */
2597: p = npfd_reserved;
2598: for (i = 0; i < sc->channels_alloc; i++)
2599: channel_prepare_pollfd(sc->channels[i], &p, *pfdp, npfd);
2600: *npfd_activep = p;
2601: }
2602:
2603: static void
1.415 djm 2604: fd_ready(Channel *c, int p, struct pollfd *pfds, u_int npfd, int fd,
1.411 djm 2605: const char *what, u_int revents_mask, u_int ready)
2606: {
2607: struct pollfd *pfd = &pfds[p];
1.410 djm 2608:
1.411 djm 2609: if (fd == -1)
2610: return;
1.415 djm 2611: if (p == -1 || (u_int)p >= npfd)
2612: fatal_f("channel %d: bad pfd %d (max %u)", c->self, p, npfd);
1.411 djm 2613: dump_channel_poll(__func__, what, c, p, pfd);
2614: if (pfd->fd != fd) {
2615: fatal("channel %d: inconsistent %s fd=%d pollfd[%u].fd %d "
2616: "r%d w%d e%d s%d", c->self, what, fd, p, pfd->fd,
2617: c->rfd, c->wfd, c->efd, c->sock);
2618: }
2619: if ((pfd->revents & POLLNVAL) != 0) {
2620: fatal("channel %d: invalid %s pollfd[%u].fd %d r%d w%d e%d s%d",
2621: c->self, what, p, pfd->fd, c->rfd, c->wfd, c->efd, c->sock);
1.410 djm 2622: }
1.411 djm 2623: if ((pfd->revents & (revents_mask|POLLHUP|POLLERR)) != 0)
2624: c->io_ready |= ready & c->io_want;
1.41 markus 2625: }
2626:
1.121 markus 2627: /*
1.411 djm 2628: * After poll, perform any appropriate operations for channels which have
1.121 markus 2629: * events pending.
2630: */
1.49 markus 2631: void
1.411 djm 2632: channel_after_poll(struct ssh *ssh, struct pollfd *pfd, u_int npfd)
1.41 markus 2633: {
1.410 djm 2634: struct ssh_channels *sc = ssh->chanctxt;
1.415 djm 2635: u_int i;
2636: int p;
1.410 djm 2637: Channel *c;
2638:
1.411 djm 2639: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2640: for (p = 0; p < (int)npfd; p++) {
1.411 djm 2641: if (pfd[p].revents == 0)
2642: continue;
2643: debug_f("pfd[%u].fd %d rev 0x%04x",
2644: p, pfd[p].fd, pfd[p].revents);
2645: }
2646: #endif
2647:
2648: /* Convert pollfd into c->io_ready */
2649: for (i = 0; i < sc->channels_alloc; i++) {
1.410 djm 2650: c = sc->channels[i];
1.415 djm 2651: if (c == NULL)
1.410 djm 2652: continue;
1.411 djm 2653: /* if rfd is shared with efd/sock then wfd should be too */
2654: if (c->rfd != -1 && c->wfd != -1 && c->rfd != c->wfd &&
2655: (c->rfd == c->efd || c->rfd == c->sock)) {
2656: /* Shouldn't happen */
2657: fatal_f("channel %d: unexpected fds r%d w%d e%d s%d",
2658: c->self, c->rfd, c->wfd, c->efd, c->sock);
2659: }
1.410 djm 2660: c->io_ready = 0;
1.411 djm 2661: /* rfd, potentially shared with wfd, efd and sock */
1.415 djm 2662: if (c->rfd != -1 && (p = c->pfds[0]) != -1) {
2663: fd_ready(c, p, pfd, npfd, c->rfd,
2664: "rfd", POLLIN, SSH_CHAN_IO_RFD);
1.411 djm 2665: if (c->rfd == c->wfd) {
1.415 djm 2666: fd_ready(c, p, pfd, npfd, c->wfd,
2667: "wfd/r", POLLOUT, SSH_CHAN_IO_WFD);
1.411 djm 2668: }
2669: if (c->rfd == c->efd) {
1.415 djm 2670: fd_ready(c, p, pfd, npfd, c->efd,
2671: "efdr/r", POLLIN, SSH_CHAN_IO_EFD_R);
2672: fd_ready(c, p, pfd, npfd, c->efd,
2673: "efdw/r", POLLOUT, SSH_CHAN_IO_EFD_W);
1.411 djm 2674: }
2675: if (c->rfd == c->sock) {
1.415 djm 2676: fd_ready(c, p, pfd, npfd, c->sock,
2677: "sockr/r", POLLIN, SSH_CHAN_IO_SOCK_R);
2678: fd_ready(c, p, pfd, npfd, c->sock,
2679: "sockw/r", POLLOUT, SSH_CHAN_IO_SOCK_W);
1.411 djm 2680: }
1.415 djm 2681: dump_channel_poll(__func__, "rfd", c, p, pfd);
1.411 djm 2682: }
2683: /* wfd */
1.415 djm 2684: if (c->wfd != -1 && c->wfd != c->rfd &&
2685: (p = c->pfds[1]) != -1) {
2686: fd_ready(c, p, pfd, npfd, c->wfd,
2687: "wfd", POLLOUT, SSH_CHAN_IO_WFD);
2688: dump_channel_poll(__func__, "wfd", c, p, pfd);
1.411 djm 2689: }
2690: /* efd */
1.415 djm 2691: if (c->efd != -1 && c->efd != c->rfd &&
2692: (p = c->pfds[2]) != -1) {
2693: fd_ready(c, p, pfd, npfd, c->efd,
2694: "efdr", POLLIN, SSH_CHAN_IO_EFD_R);
2695: fd_ready(c, p, pfd, npfd, c->efd,
2696: "efdw", POLLOUT, SSH_CHAN_IO_EFD_W);
2697: dump_channel_poll(__func__, "efd", c, p, pfd);
1.411 djm 2698: }
2699: /* sock */
1.415 djm 2700: if (c->sock != -1 && c->sock != c->rfd &&
2701: (p = c->pfds[3]) != -1) {
2702: fd_ready(c, p, pfd, npfd, c->sock,
2703: "sockr", POLLIN, SSH_CHAN_IO_SOCK_R);
2704: fd_ready(c, p, pfd, npfd, c->sock,
2705: "sockw", POLLOUT, SSH_CHAN_IO_SOCK_W);
2706: dump_channel_poll(__func__, "sock", c, p, pfd);
1.411 djm 2707: }
1.410 djm 2708: }
2709: channel_handler(ssh, CHAN_POST, NULL);
1.367 djm 2710: }
2711:
2712: /*
2713: * Enqueue data for channels with open or draining c->input.
2714: */
2715: static void
2716: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2717: {
1.373 djm 2718: size_t len, plen;
2719: const u_char *pkt;
1.367 djm 2720: int r;
2721:
2722: if ((len = sshbuf_len(c->input)) == 0) {
2723: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2724: /*
2725: * input-buffer is empty and read-socket shutdown:
2726: * tell peer, that we will not send more data:
2727: * send IEOF.
2728: * hack for extended data: delay EOF if EFD still
2729: * in use.
2730: */
2731: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2732: debug2("channel %d: "
2733: "ibuf_empty delayed efd %d/(%zu)",
2734: c->self, c->efd, sshbuf_len(c->extended));
2735: else
2736: chan_ibuf_empty(ssh, c);
2737: }
2738: return;
2739: }
2740:
1.368 djm 2741: if (!c->have_remote_id)
1.403 djm 2742: fatal_f("channel %d: no remote id", c->self);
1.368 djm 2743:
1.367 djm 2744: if (c->datagram) {
2745: /* Check datagram will fit; drop if not */
1.373 djm 2746: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
1.403 djm 2747: fatal_fr(r, "channel %i: get datagram", c->self);
1.367 djm 2748: /*
2749: * XXX this does tail-drop on the datagram queue which is
2750: * usually suboptimal compared to head-drop. Better to have
2751: * backpressure at read time? (i.e. read + discard)
2752: */
1.373 djm 2753: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2754: debug("channel %d: datagram too big", c->self);
2755: return;
2756: }
2757: /* Enqueue it */
2758: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2759: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2760: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.403 djm 2761: (r = sshpkt_send(ssh)) != 0)
2762: fatal_fr(r, "channel %i: send datagram", c->self);
1.373 djm 2763: c->remote_window -= plen;
1.367 djm 2764: return;
2765: }
2766:
2767: /* Enqueue packet for buffered data. */
2768: if (len > c->remote_window)
2769: len = c->remote_window;
2770: if (len > c->remote_maxpacket)
2771: len = c->remote_maxpacket;
2772: if (len == 0)
2773: return;
2774: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2775: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2776: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
1.403 djm 2777: (r = sshpkt_send(ssh)) != 0)
2778: fatal_fr(r, "channel %i: send data", c->self);
1.367 djm 2779: if ((r = sshbuf_consume(c->input, len)) != 0)
1.403 djm 2780: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2781: c->remote_window -= len;
1.41 markus 2782: }
2783:
1.367 djm 2784: /*
2785: * Enqueue data for channels with open c->extended in read mode.
2786: */
2787: static void
2788: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2789: {
2790: size_t len;
2791: int r;
2792:
2793: if ((len = sshbuf_len(c->extended)) == 0)
2794: return;
2795:
2796: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2797: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2798: if (len > c->remote_window)
2799: len = c->remote_window;
2800: if (len > c->remote_maxpacket)
2801: len = c->remote_maxpacket;
2802: if (len == 0)
2803: return;
1.368 djm 2804: if (!c->have_remote_id)
1.403 djm 2805: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2806: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2807: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2808: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2809: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
1.403 djm 2810: (r = sshpkt_send(ssh)) != 0)
2811: fatal_fr(r, "channel %i: data", c->self);
1.367 djm 2812: if ((r = sshbuf_consume(c->extended, len)) != 0)
1.403 djm 2813: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2814: c->remote_window -= len;
2815: debug2("channel %d: sent ext data %zu", c->self, len);
2816: }
1.121 markus 2817:
1.84 markus 2818: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2819: void
1.367 djm 2820: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2821: {
1.367 djm 2822: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2823: Channel *c;
1.367 djm 2824: u_int i;
1.1 deraadt 2825:
1.367 djm 2826: for (i = 0; i < sc->channels_alloc; i++) {
2827: c = sc->channels[i];
1.113 markus 2828: if (c == NULL)
2829: continue;
1.37 markus 2830:
1.121 markus 2831: /*
2832: * We are only interested in channels that can have buffered
2833: * incoming data.
2834: */
1.358 djm 2835: if (c->type != SSH_CHANNEL_OPEN)
2836: continue;
2837: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2838: /* XXX is this true? */
1.367 djm 2839: debug3("channel %d: will not send data after close",
2840: c->self);
1.44 markus 2841: continue;
2842: }
1.25 markus 2843:
2844: /* Get the amount of buffered data for this channel. */
1.367 djm 2845: if (c->istate == CHAN_INPUT_OPEN ||
2846: c->istate == CHAN_INPUT_WAIT_DRAIN)
2847: channel_output_poll_input_open(ssh, c);
1.44 markus 2848: /* Send extended data, i.e. stderr */
1.358 djm 2849: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2850: c->extended_usage == CHAN_EXTENDED_READ)
2851: channel_output_poll_extended_read(ssh, c);
1.25 markus 2852: }
1.1 deraadt 2853: }
2854:
1.354 markus 2855: /* -- mux proxy support */
2856:
2857: /*
2858: * When multiplexing channel messages for mux clients we have to deal
2859: * with downstream messages from the mux client and upstream messages
2860: * from the ssh server:
2861: * 1) Handling downstream messages is straightforward and happens
2862: * in channel_proxy_downstream():
2863: * - We forward all messages (mostly) unmodified to the server.
2864: * - However, in order to route messages from upstream to the correct
2865: * downstream client, we have to replace the channel IDs used by the
2866: * mux clients with a unique channel ID because the mux clients might
2867: * use conflicting channel IDs.
2868: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2869: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2870: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2871: * with the newly allocated channel ID.
2872: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 2873: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 2874: * is then translated back to the original mux client ID.
2875: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2876: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2877: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2878: * downstream mux client are removed.
2879: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2880: * requires more work, because they are not addressed to a specific
2881: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2882: * out whether the request is addressed to the local client or a
2883: * specific downstream client based on the listen-address/port.
1.380 djm 2884: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 2885: * not supported as the matching session/channel cannot be identified
2886: * easily.
2887: */
2888:
2889: /*
2890: * receive packets from downstream mux clients:
2891: * channel callback fired on read from mux client, creates
2892: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2893: * on channel creation.
2894: */
2895: int
1.367 djm 2896: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2897: {
2898: Channel *c = NULL;
2899: struct sshbuf *original = NULL, *modified = NULL;
2900: const u_char *cp;
2901: char *ctype = NULL, *listen_host = NULL;
2902: u_char type;
2903: size_t have;
1.370 djm 2904: int ret = -1, r;
1.355 djm 2905: u_int id, remote_id, listen_port;
1.354 markus 2906:
1.367 djm 2907: /* sshbuf_dump(downstream->input, stderr); */
2908: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2909: != 0) {
1.403 djm 2910: error_fr(r, "parse");
1.354 markus 2911: return -1;
2912: }
2913: if (have < 2) {
1.403 djm 2914: error_f("short message");
1.354 markus 2915: return -1;
2916: }
2917: type = cp[1];
2918: /* skip padlen + type */
2919: cp += 2;
2920: have -= 2;
2921: if (ssh_packet_log_type(type))
1.403 djm 2922: debug3_f("channel %u: down->up: type %u",
1.354 markus 2923: downstream->self, type);
2924:
2925: switch (type) {
2926: case SSH2_MSG_CHANNEL_OPEN:
2927: if ((original = sshbuf_from(cp, have)) == NULL ||
2928: (modified = sshbuf_new()) == NULL) {
1.403 djm 2929: error_f("alloc");
1.354 markus 2930: goto out;
2931: }
2932: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2933: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 2934: error_fr(r, "parse");
1.354 markus 2935: goto out;
2936: }
1.367 djm 2937: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 2938: -1, -1, -1, 0, 0, 0, ctype, 1);
1.354 markus 2939: c->mux_ctx = downstream; /* point to mux client */
2940: c->mux_downstream_id = id; /* original downstream id */
2941: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2942: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2943: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 2944: error_fr(r, "compose");
1.367 djm 2945: channel_free(ssh, c);
1.354 markus 2946: goto out;
2947: }
2948: break;
2949: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2950: /*
2951: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2952: * need to parse 'remote_id' instead of 'ctype'.
2953: */
2954: if ((original = sshbuf_from(cp, have)) == NULL ||
2955: (modified = sshbuf_new()) == NULL) {
1.403 djm 2956: error_f("alloc");
1.354 markus 2957: goto out;
2958: }
2959: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2960: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 2961: error_fr(r, "parse");
1.354 markus 2962: goto out;
2963: }
1.367 djm 2964: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 2965: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
1.354 markus 2966: c->mux_ctx = downstream; /* point to mux client */
2967: c->mux_downstream_id = id;
2968: c->remote_id = remote_id;
1.368 djm 2969: c->have_remote_id = 1;
1.354 markus 2970: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2971: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2972: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 2973: error_fr(r, "compose");
1.367 djm 2974: channel_free(ssh, c);
1.354 markus 2975: goto out;
2976: }
2977: break;
2978: case SSH2_MSG_GLOBAL_REQUEST:
2979: if ((original = sshbuf_from(cp, have)) == NULL) {
1.403 djm 2980: error_f("alloc");
1.354 markus 2981: goto out;
2982: }
2983: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
1.403 djm 2984: error_fr(r, "parse");
1.354 markus 2985: goto out;
2986: }
2987: if (strcmp(ctype, "tcpip-forward") != 0) {
1.403 djm 2988: error_f("unsupported request %s", ctype);
1.354 markus 2989: goto out;
2990: }
2991: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2992: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2993: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
1.403 djm 2994: error_fr(r, "parse");
1.354 markus 2995: goto out;
2996: }
1.355 djm 2997: if (listen_port > 65535) {
1.403 djm 2998: error_f("tcpip-forward for %s: bad port %u",
2999: listen_host, listen_port);
1.355 djm 3000: goto out;
3001: }
1.354 markus 3002: /* Record that connection to this host/port is permitted. */
1.381 djm 3003: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 3004: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 3005: listen_host = NULL;
3006: break;
3007: case SSH2_MSG_CHANNEL_CLOSE:
3008: if (have < 4)
3009: break;
3010: remote_id = PEEK_U32(cp);
1.367 djm 3011: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 3012: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 3013: channel_free(ssh, c);
1.354 markus 3014: else
3015: c->flags |= CHAN_CLOSE_SENT;
3016: }
3017: break;
3018: }
3019: if (modified) {
3020: if ((r = sshpkt_start(ssh, type)) != 0 ||
3021: (r = sshpkt_putb(ssh, modified)) != 0 ||
3022: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3023: error_fr(r, "send");
1.354 markus 3024: goto out;
3025: }
3026: } else {
3027: if ((r = sshpkt_start(ssh, type)) != 0 ||
3028: (r = sshpkt_put(ssh, cp, have)) != 0 ||
3029: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3030: error_fr(r, "send");
1.354 markus 3031: goto out;
3032: }
3033: }
3034: ret = 0;
3035: out:
3036: free(ctype);
3037: free(listen_host);
3038: sshbuf_free(original);
3039: sshbuf_free(modified);
3040: return ret;
3041: }
3042:
3043: /*
3044: * receive packets from upstream server and de-multiplex packets
3045: * to correct downstream:
3046: * implemented as a helper for channel input handlers,
3047: * replaces local (proxy) channel ID with downstream channel ID.
3048: */
3049: int
1.363 markus 3050: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 3051: {
3052: struct sshbuf *b = NULL;
3053: Channel *downstream;
3054: const u_char *cp = NULL;
3055: size_t len;
3056: int r;
3057:
3058: /*
3059: * When receiving packets from the peer we need to check whether we
3060: * need to forward the packets to the mux client. In this case we
1.380 djm 3061: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 3062: * so we can cleanup the channel.
3063: */
3064: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
3065: return 0;
3066: if ((downstream = c->mux_ctx) == NULL)
3067: return 0;
3068: switch (type) {
3069: case SSH2_MSG_CHANNEL_CLOSE:
3070: case SSH2_MSG_CHANNEL_DATA:
3071: case SSH2_MSG_CHANNEL_EOF:
3072: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
3073: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3074: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
3075: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
3076: case SSH2_MSG_CHANNEL_SUCCESS:
3077: case SSH2_MSG_CHANNEL_FAILURE:
3078: case SSH2_MSG_CHANNEL_REQUEST:
3079: break;
3080: default:
1.403 djm 3081: debug2_f("channel %u: unsupported type %u", c->self, type);
1.354 markus 3082: return 0;
3083: }
3084: if ((b = sshbuf_new()) == NULL) {
1.403 djm 3085: error_f("alloc reply");
1.354 markus 3086: goto out;
3087: }
3088: /* get remaining payload (after id) */
3089: cp = sshpkt_ptr(ssh, &len);
3090: if (cp == NULL) {
1.403 djm 3091: error_f("no packet");
1.354 markus 3092: goto out;
3093: }
3094: /* translate id and send to muxclient */
3095: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
3096: (r = sshbuf_put_u8(b, type)) != 0 ||
3097: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
3098: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 3099: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.403 djm 3100: error_fr(r, "compose muxclient");
1.354 markus 3101: goto out;
3102: }
3103: /* sshbuf_dump(b, stderr); */
3104: if (ssh_packet_log_type(type))
1.403 djm 3105: debug3_f("channel %u: up->down: type %u", c->self, type);
1.354 markus 3106: out:
3107: /* update state */
3108: switch (type) {
3109: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3110: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 3111: if (cp && len > 4) {
1.354 markus 3112: c->remote_id = PEEK_U32(cp);
1.368 djm 3113: c->have_remote_id = 1;
3114: }
1.354 markus 3115: break;
3116: case SSH2_MSG_CHANNEL_CLOSE:
3117: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 3118: channel_free(ssh, c);
1.354 markus 3119: else
3120: c->flags |= CHAN_CLOSE_RCVD;
3121: break;
3122: }
3123: sshbuf_free(b);
3124: return 1;
3125: }
1.121 markus 3126:
3127: /* -- protocol input */
1.249 djm 3128:
1.367 djm 3129: /* Parse a channel ID from the current packet */
3130: static int
3131: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
3132: {
3133: u_int32_t id;
3134: int r;
3135:
3136: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
1.403 djm 3137: error_r(r, "%s: parse id", where);
1.367 djm 3138: ssh_packet_disconnect(ssh, "Invalid %s message", what);
3139: }
3140: if (id > INT_MAX) {
1.403 djm 3141: error_r(r, "%s: bad channel id %u", where, id);
1.367 djm 3142: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
3143: }
3144: return (int)id;
3145: }
3146:
3147: /* Lookup a channel from an ID in the current packet */
3148: static Channel *
3149: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
3150: {
3151: int id = channel_parse_id(ssh, where, what);
3152: Channel *c;
3153:
3154: if ((c = channel_lookup(ssh, id)) == NULL) {
3155: ssh_packet_disconnect(ssh,
3156: "%s packet referred to nonexistent channel %d", what, id);
3157: }
3158: return c;
3159: }
3160:
1.339 markus 3161: int
1.363 markus 3162: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3163: {
1.332 djm 3164: const u_char *data;
1.367 djm 3165: size_t data_len, win_len;
3166: Channel *c = channel_from_packet_id(ssh, __func__, "data");
3167: int r;
1.25 markus 3168:
1.363 markus 3169: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3170: return 0;
1.25 markus 3171:
3172: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 3173: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 3174: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
3175: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 3176: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 3177: return 0;
1.37 markus 3178:
1.25 markus 3179: /* Get the data. */
1.389 djm 3180: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3181: (r = sshpkt_get_end(ssh)) != 0)
1.403 djm 3182: fatal_fr(r, "channel %i: get data", c->self);
1.367 djm 3183:
1.309 djm 3184: win_len = data_len;
3185: if (c->datagram)
3186: win_len += 4; /* string length header */
1.200 markus 3187:
3188: /*
1.367 djm 3189: * The sending side reduces its window as it sends data, so we
3190: * must 'fake' consumption of the data in order to ensure that window
3191: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 3192: */
1.358 djm 3193: if (c->ostate != CHAN_OUTPUT_OPEN) {
3194: c->local_window -= win_len;
3195: c->local_consumed += win_len;
1.339 markus 3196: return 0;
1.200 markus 3197: }
1.41 markus 3198:
1.358 djm 3199: if (win_len > c->local_maxpacket) {
1.367 djm 3200: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 3201: c->self, win_len, c->local_maxpacket);
1.367 djm 3202: return 0;
1.358 djm 3203: }
3204: if (win_len > c->local_window) {
1.367 djm 3205: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 3206: c->self, win_len, c->local_window);
3207: return 0;
1.44 markus 3208: }
1.358 djm 3209: c->local_window -= win_len;
3210:
1.367 djm 3211: if (c->datagram) {
3212: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
1.403 djm 3213: fatal_fr(r, "channel %i: append datagram", c->self);
1.367 djm 3214: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
1.403 djm 3215: fatal_fr(r, "channel %i: append data", c->self);
1.367 djm 3216:
1.339 markus 3217: return 0;
1.1 deraadt 3218: }
1.121 markus 3219:
1.339 markus 3220: int
1.363 markus 3221: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 3222: {
1.367 djm 3223: const u_char *data;
3224: size_t data_len;
3225: u_int32_t tcode;
3226: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
3227: int r;
1.44 markus 3228:
1.363 markus 3229: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3230: return 0;
1.44 markus 3231: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 3232: logit("channel %d: ext data for non open", c->self);
1.339 markus 3233: return 0;
1.172 markus 3234: }
3235: if (c->flags & CHAN_EOF_RCVD) {
1.404 djm 3236: if (ssh->compat & SSH_BUG_EXTEOF)
1.367 djm 3237: debug("channel %d: accepting ext data after eof",
3238: c->self);
1.172 markus 3239: else
1.367 djm 3240: ssh_packet_disconnect(ssh, "Received extended_data "
3241: "after EOF on channel %d.", c->self);
3242: }
3243:
3244: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
1.403 djm 3245: error_fr(r, "parse tcode");
1.367 djm 3246: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3247: }
3248: if (c->efd == -1 ||
3249: c->extended_usage != CHAN_EXTENDED_WRITE ||
3250: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3251: logit("channel %d: bad ext data", c->self);
1.339 markus 3252: return 0;
1.44 markus 3253: }
1.389 djm 3254: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3255: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3256: error_fr(r, "parse data");
1.367 djm 3257: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3258: }
3259:
1.44 markus 3260: if (data_len > c->local_window) {
1.367 djm 3261: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3262: c->self, data_len, c->local_window);
1.339 markus 3263: return 0;
1.44 markus 3264: }
1.367 djm 3265: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3266: /* XXX sshpkt_getb? */
3267: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
1.403 djm 3268: error_fr(r, "append");
1.44 markus 3269: c->local_window -= data_len;
1.339 markus 3270: return 0;
1.44 markus 3271: }
3272:
1.339 markus 3273: int
1.363 markus 3274: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3275: {
1.367 djm 3276: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3277: int r;
1.367 djm 3278:
1.389 djm 3279: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3280: error_fr(r, "parse data");
1.389 djm 3281: ssh_packet_disconnect(ssh, "Invalid ieof message");
3282: }
1.41 markus 3283:
1.363 markus 3284: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3285: return 0;
1.367 djm 3286: chan_rcvd_ieof(ssh, c);
1.133 markus 3287:
3288: /* XXX force input close */
1.156 markus 3289: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3290: debug("channel %d: FORCE input drain", c->self);
3291: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3292: if (sshbuf_len(c->input) == 0)
3293: chan_ibuf_empty(ssh, c);
1.133 markus 3294: }
1.339 markus 3295: return 0;
1.41 markus 3296: }
1.1 deraadt 3297:
1.339 markus 3298: int
1.363 markus 3299: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3300: {
1.367 djm 3301: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3302: int r;
1.151 markus 3303:
1.363 markus 3304: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3305: return 0;
1.389 djm 3306: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3307: error_fr(r, "parse data");
1.389 djm 3308: ssh_packet_disconnect(ssh, "Invalid oclose message");
3309: }
1.367 djm 3310: chan_rcvd_oclose(ssh, c);
1.339 markus 3311: return 0;
1.1 deraadt 3312: }
3313:
1.339 markus 3314: int
1.363 markus 3315: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3316: {
1.367 djm 3317: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3318: u_int32_t remote_window, remote_maxpacket;
3319: int r;
1.25 markus 3320:
1.363 markus 3321: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3322: return 0;
3323: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3324: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3325: "non-opening channel %d.", c->self);
3326: /*
3327: * Record the remote channel number and mark that the channel
3328: * is now open.
3329: */
1.368 djm 3330: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3331: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3332: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3333: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3334: error_fr(r, "window/maxpacket");
1.389 djm 3335: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3336: }
3337:
1.368 djm 3338: c->have_remote_id = 1;
1.367 djm 3339: c->remote_window = remote_window;
3340: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3341: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3342: if (c->open_confirm) {
1.403 djm 3343: debug2_f("channel %d: callback start", c->self);
1.367 djm 3344: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
1.403 djm 3345: debug2_f("channel %d: callback done", c->self);
1.44 markus 3346: }
1.358 djm 3347: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3348: c->remote_window, c->remote_maxpacket);
1.339 markus 3349: return 0;
1.1 deraadt 3350: }
3351:
1.127 itojun 3352: static char *
1.114 markus 3353: reason2txt(int reason)
3354: {
1.143 deraadt 3355: switch (reason) {
1.114 markus 3356: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3357: return "administratively prohibited";
3358: case SSH2_OPEN_CONNECT_FAILED:
3359: return "connect failed";
3360: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3361: return "unknown channel type";
3362: case SSH2_OPEN_RESOURCE_SHORTAGE:
3363: return "resource shortage";
3364: }
1.117 stevesk 3365: return "unknown reason";
1.114 markus 3366: }
3367:
1.339 markus 3368: int
1.363 markus 3369: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3370: {
1.367 djm 3371: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3372: u_int32_t reason;
3373: char *msg = NULL;
3374: int r;
1.25 markus 3375:
1.363 markus 3376: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3377: return 0;
3378: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3379: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3380: "non-opening channel %d.", c->self);
3381: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
1.403 djm 3382: error_fr(r, "parse reason");
1.389 djm 3383: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3384: }
1.378 djm 3385: /* skip language */
3386: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3387: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3388: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3389: error_fr(r, "parse msg/lang");
1.389 djm 3390: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3391: }
1.367 djm 3392: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3393: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3394: free(msg);
3395: if (c->open_confirm) {
1.403 djm 3396: debug2_f("channel %d: callback start", c->self);
1.367 djm 3397: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
1.403 djm 3398: debug2_f("channel %d: callback done", c->self);
1.44 markus 3399: }
1.291 djm 3400: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3401: chan_mark_dead(ssh, c);
1.339 markus 3402: return 0;
1.44 markus 3403: }
3404:
1.339 markus 3405: int
1.363 markus 3406: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3407: {
1.367 djm 3408: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3409: Channel *c;
1.367 djm 3410: u_int32_t adjust;
3411: u_int new_rwin;
3412: int r;
1.1 deraadt 3413:
1.367 djm 3414: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3415: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3416: return 0;
1.372 markus 3417: }
1.367 djm 3418:
1.363 markus 3419: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3420: return 0;
1.389 djm 3421: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3422: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3423: error_fr(r, "parse adjust");
1.389 djm 3424: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3425: }
3426: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3427: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3428: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3429: c->self, adjust, c->remote_window);
3430: }
3431: c->remote_window = new_rwin;
1.339 markus 3432: return 0;
1.121 markus 3433: }
1.1 deraadt 3434:
1.339 markus 3435: int
1.363 markus 3436: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3437: {
1.367 djm 3438: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3439: Channel *c;
3440: struct channel_confirm *cc;
3441:
3442: /* Reset keepalive timeout */
1.389 djm 3443: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3444:
1.403 djm 3445: debug2_f("type %d id %d", type, id);
1.275 djm 3446:
1.367 djm 3447: if ((c = channel_lookup(ssh, id)) == NULL) {
1.403 djm 3448: logit_f("%d: unknown", id);
1.339 markus 3449: return 0;
1.367 djm 3450: }
1.363 markus 3451: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3452: return 0;
1.394 dtucker 3453: if (sshpkt_get_end(ssh) != 0)
1.389 djm 3454: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3455: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3456: return 0;
1.367 djm 3457: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3458: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 3459: freezero(cc, sizeof(*cc));
1.339 markus 3460: return 0;
1.275 djm 3461: }
1.121 markus 3462:
3463: /* -- tcp forwarding */
1.135 markus 3464:
3465: void
1.367 djm 3466: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3467: {
1.367 djm 3468: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3469: }
1.121 markus 3470:
1.312 djm 3471:
3472: /*
3473: * Determine whether or not a port forward listens to loopback, the
3474: * specified address or wildcard. On the client, a specified bind
3475: * address will always override gateway_ports. On the server, a
3476: * gateway_ports of 1 (``yes'') will override the client's specification
3477: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3478: * will bind to whatever address the client asked for.
3479: *
3480: * Special-case listen_addrs are:
3481: *
3482: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3483: * "" (empty string), "*" -> wildcard v4/v6
3484: * "localhost" -> loopback v4/v6
1.334 djm 3485: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3486: */
3487: static const char *
1.389 djm 3488: channel_fwd_bind_addr(struct ssh *ssh, const char *listen_addr, int *wildcardp,
1.336 millert 3489: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3490: {
3491: const char *addr = NULL;
3492: int wildcard = 0;
3493:
3494: if (listen_addr == NULL) {
3495: /* No address specified: default to gateway_ports setting */
1.336 millert 3496: if (fwd_opts->gateway_ports)
1.312 djm 3497: wildcard = 1;
1.336 millert 3498: } else if (fwd_opts->gateway_ports || is_client) {
1.404 djm 3499: if (((ssh->compat & SSH_OLD_FORWARD_ADDR) &&
1.312 djm 3500: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3501: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3502: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3503: wildcard = 1;
1.326 djm 3504: /*
3505: * Notify client if they requested a specific listen
3506: * address and it was overridden.
3507: */
3508: if (*listen_addr != '\0' &&
3509: strcmp(listen_addr, "0.0.0.0") != 0 &&
3510: strcmp(listen_addr, "*") != 0) {
1.389 djm 3511: ssh_packet_send_debug(ssh,
3512: "Forwarding listen address "
1.326 djm 3513: "\"%s\" overridden by server "
3514: "GatewayPorts", listen_addr);
3515: }
1.334 djm 3516: } else if (strcmp(listen_addr, "localhost") != 0 ||
3517: strcmp(listen_addr, "127.0.0.1") == 0 ||
3518: strcmp(listen_addr, "::1") == 0) {
1.395 djm 3519: /*
3520: * Accept explicit localhost address when
3521: * GatewayPorts=yes. The "localhost" hostname is
3522: * deliberately skipped here so it will listen on all
3523: * available local address families.
3524: */
1.334 djm 3525: addr = listen_addr;
1.326 djm 3526: }
1.334 djm 3527: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3528: strcmp(listen_addr, "::1") == 0) {
3529: /*
3530: * If a specific IPv4/IPv6 localhost address has been
3531: * requested then accept it even if gateway_ports is in
3532: * effect. This allows the client to prefer IPv4 or IPv6.
3533: */
3534: addr = listen_addr;
1.312 djm 3535: }
3536: if (wildcardp != NULL)
3537: *wildcardp = wildcard;
3538: return addr;
3539: }
3540:
1.160 markus 3541: static int
1.367 djm 3542: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3543: struct Forward *fwd, int *allocated_listen_port,
3544: struct ForwardOptions *fwd_opts)
1.25 markus 3545: {
1.113 markus 3546: Channel *c;
1.226 djm 3547: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3548: struct addrinfo hints, *ai, *aitop;
1.212 djm 3549: const char *host, *addr;
1.35 markus 3550: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3551: in_port_t *lport_p;
1.25 markus 3552:
1.212 djm 3553: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3554:
1.344 millert 3555: if (is_client && fwd->connect_path != NULL) {
3556: host = fwd->connect_path;
3557: } else {
3558: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3559: fwd->listen_host : fwd->connect_host;
3560: if (host == NULL) {
3561: error("No forward host name.");
3562: return 0;
3563: }
3564: if (strlen(host) >= NI_MAXHOST) {
3565: error("Forward host name too long.");
3566: return 0;
3567: }
1.87 markus 3568: }
1.25 markus 3569:
1.312 djm 3570: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3571: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3572: is_client, fwd_opts);
1.403 djm 3573: debug3_f("type %d wildcard %d addr %s", type, wildcard,
3574: (addr == NULL) ? "NULL" : addr);
1.212 djm 3575:
3576: /*
1.35 markus 3577: * getaddrinfo returns a loopback address if the hostname is
3578: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3579: */
1.35 markus 3580: memset(&hints, 0, sizeof(hints));
1.367 djm 3581: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3582: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3583: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3584: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3585: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3586: if (addr == NULL) {
3587: /* This really shouldn't happen */
1.389 djm 3588: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3589: ssh_gai_strerror(r));
1.212 djm 3590: } else {
1.403 djm 3591: error_f("getaddrinfo(%.64s): %s", addr,
1.271 dtucker 3592: ssh_gai_strerror(r));
1.212 djm 3593: }
1.218 markus 3594: return 0;
1.212 djm 3595: }
1.295 djm 3596: if (allocated_listen_port != NULL)
3597: *allocated_listen_port = 0;
1.35 markus 3598: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3599: switch (ai->ai_family) {
3600: case AF_INET:
3601: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3602: sin_port;
3603: break;
3604: case AF_INET6:
3605: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3606: sin6_port;
3607: break;
3608: default:
1.35 markus 3609: continue;
1.295 djm 3610: }
3611: /*
3612: * If allocating a port for -R forwards, then use the
3613: * same port for all address families.
3614: */
1.367 djm 3615: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3616: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3617: *allocated_listen_port > 0)
1.295 djm 3618: *lport_p = htons(*allocated_listen_port);
3619:
1.35 markus 3620: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3621: strport, sizeof(strport),
3622: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.403 djm 3623: error_f("getnameinfo failed");
1.35 markus 3624: continue;
3625: }
3626: /* Create a port to listen for the host. */
1.300 dtucker 3627: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 3628: if (sock == -1) {
1.35 markus 3629: /* this is no error since kernel may not support ipv6 */
1.377 djm 3630: verbose("socket [%s]:%s: %.100s", ntop, strport,
3631: strerror(errno));
1.35 markus 3632: continue;
3633: }
1.226 djm 3634:
1.376 djm 3635: set_reuseaddr(sock);
1.182 stevesk 3636:
1.295 djm 3637: debug("Local forwarding listening on %s port %s.",
3638: ntop, strport);
1.35 markus 3639:
3640: /* Bind the socket to the address. */
1.393 deraadt 3641: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3642: /*
3643: * address can be in if use ipv6 address is
3644: * already bound
3645: */
1.377 djm 3646: verbose("bind [%s]:%s: %.100s",
3647: ntop, strport, strerror(errno));
1.35 markus 3648: close(sock);
3649: continue;
3650: }
3651: /* Start listening for connections on the socket. */
1.393 deraadt 3652: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3653: error("listen [%s]:%s: %.100s", ntop, strport,
3654: strerror(errno));
1.35 markus 3655: close(sock);
3656: continue;
3657: }
1.295 djm 3658:
3659: /*
1.336 millert 3660: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3661: * record what we got.
3662: */
1.367 djm 3663: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3664: fwd->listen_port == 0 &&
1.295 djm 3665: allocated_listen_port != NULL &&
3666: *allocated_listen_port == 0) {
1.350 djm 3667: *allocated_listen_port = get_local_port(sock);
1.295 djm 3668: debug("Allocated listen port %d",
3669: *allocated_listen_port);
3670: }
3671:
1.35 markus 3672: /* Allocate a channel number for the socket. */
1.367 djm 3673: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3674: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3675: 0, "port listener", 1);
1.293 djm 3676: c->path = xstrdup(host);
1.336 millert 3677: c->host_port = fwd->connect_port;
1.312 djm 3678: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3679: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.404 djm 3680: !(ssh->compat & SSH_BUG_DYNAMIC_RPORT))
1.315 markus 3681: c->listening_port = *allocated_listen_port;
3682: else
1.336 millert 3683: c->listening_port = fwd->listen_port;
1.35 markus 3684: success = 1;
3685: }
3686: if (success == 0)
1.403 djm 3687: error_f("cannot listen to port: %d", fwd->listen_port);
1.35 markus 3688: freeaddrinfo(aitop);
1.87 markus 3689: return success;
1.25 markus 3690: }
1.1 deraadt 3691:
1.336 millert 3692: static int
1.367 djm 3693: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3694: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3695: {
3696: struct sockaddr_un sunaddr;
3697: const char *path;
3698: Channel *c;
3699: int port, sock;
3700: mode_t omask;
3701:
3702: switch (type) {
3703: case SSH_CHANNEL_UNIX_LISTENER:
3704: if (fwd->connect_path != NULL) {
3705: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3706: error("Local connecting path too long: %s",
3707: fwd->connect_path);
3708: return 0;
3709: }
3710: path = fwd->connect_path;
3711: port = PORT_STREAMLOCAL;
3712: } else {
3713: if (fwd->connect_host == NULL) {
3714: error("No forward host name.");
3715: return 0;
3716: }
3717: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3718: error("Forward host name too long.");
3719: return 0;
3720: }
3721: path = fwd->connect_host;
3722: port = fwd->connect_port;
3723: }
3724: break;
3725: case SSH_CHANNEL_RUNIX_LISTENER:
3726: path = fwd->listen_path;
3727: port = PORT_STREAMLOCAL;
3728: break;
3729: default:
1.403 djm 3730: error_f("unexpected channel type %d", type);
1.336 millert 3731: return 0;
3732: }
3733:
3734: if (fwd->listen_path == NULL) {
3735: error("No forward path name.");
3736: return 0;
3737: }
3738: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3739: error("Local listening path too long: %s", fwd->listen_path);
3740: return 0;
3741: }
3742:
1.403 djm 3743: debug3_f("type %d path %s", type, fwd->listen_path);
1.336 millert 3744:
3745: /* Start a Unix domain listener. */
3746: omask = umask(fwd_opts->streamlocal_bind_mask);
3747: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3748: fwd_opts->streamlocal_bind_unlink);
3749: umask(omask);
3750: if (sock < 0)
3751: return 0;
3752:
3753: debug("Local forwarding listening on path %s.", fwd->listen_path);
3754:
3755: /* Allocate a channel number for the socket. */
1.367 djm 3756: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3757: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3758: 0, "unix listener", 1);
3759: c->path = xstrdup(path);
3760: c->host_port = port;
3761: c->listening_port = PORT_STREAMLOCAL;
3762: c->listening_addr = xstrdup(fwd->listen_path);
3763: return 1;
3764: }
3765:
3766: static int
1.367 djm 3767: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3768: const char *host, u_short port)
1.202 djm 3769: {
1.209 avsm 3770: u_int i;
3771: int found = 0;
1.202 djm 3772:
1.367 djm 3773: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3774: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3775: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3776: continue;
3777: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
1.403 djm 3778: debug2_f("close channel %d", i);
1.367 djm 3779: channel_free(ssh, c);
1.312 djm 3780: found = 1;
3781: }
3782: }
3783:
1.367 djm 3784: return found;
1.312 djm 3785: }
3786:
1.336 millert 3787: static int
1.367 djm 3788: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3789: {
3790: u_int i;
3791: int found = 0;
3792:
1.367 djm 3793: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3794: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3795: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3796: continue;
3797: if (c->path == NULL)
3798: continue;
3799: if (strcmp(c->path, path) == 0) {
1.403 djm 3800: debug2_f("close channel %d", i);
1.367 djm 3801: channel_free(ssh, c);
1.336 millert 3802: found = 1;
3803: }
3804: }
3805:
1.367 djm 3806: return found;
1.336 millert 3807: }
3808:
1.312 djm 3809: int
1.367 djm 3810: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3811: {
1.367 djm 3812: if (fwd->listen_path != NULL) {
3813: return channel_cancel_rport_listener_streamlocal(ssh,
3814: fwd->listen_path);
3815: } else {
3816: return channel_cancel_rport_listener_tcpip(ssh,
3817: fwd->listen_host, fwd->listen_port);
3818: }
1.336 millert 3819: }
3820:
3821: static int
1.367 djm 3822: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3823: const char *lhost, u_short lport, int cport,
3824: struct ForwardOptions *fwd_opts)
1.312 djm 3825: {
3826: u_int i;
3827: int found = 0;
1.389 djm 3828: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 3829:
1.367 djm 3830: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3831: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3832: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3833: continue;
1.313 markus 3834: if (c->listening_port != lport)
1.312 djm 3835: continue;
1.313 markus 3836: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3837: /* skip dynamic forwardings */
3838: if (c->host_port == 0)
3839: continue;
3840: } else {
3841: if (c->host_port != cport)
3842: continue;
3843: }
1.312 djm 3844: if ((c->listening_addr == NULL && addr != NULL) ||
3845: (c->listening_addr != NULL && addr == NULL))
3846: continue;
3847: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.403 djm 3848: debug2_f("close channel %d", i);
1.367 djm 3849: channel_free(ssh, c);
1.202 djm 3850: found = 1;
3851: }
3852: }
3853:
1.367 djm 3854: return found;
1.202 djm 3855: }
3856:
1.336 millert 3857: static int
1.367 djm 3858: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3859: {
3860: u_int i;
3861: int found = 0;
3862:
3863: if (path == NULL) {
1.403 djm 3864: error_f("no path specified.");
1.336 millert 3865: return 0;
3866: }
3867:
1.367 djm 3868: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3869: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3870: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3871: continue;
3872: if (c->listening_addr == NULL)
3873: continue;
3874: if (strcmp(c->listening_addr, path) == 0) {
1.403 djm 3875: debug2_f("close channel %d", i);
1.367 djm 3876: channel_free(ssh, c);
1.336 millert 3877: found = 1;
3878: }
3879: }
3880:
1.367 djm 3881: return found;
1.336 millert 3882: }
3883:
3884: int
1.367 djm 3885: channel_cancel_lport_listener(struct ssh *ssh,
3886: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3887: {
1.367 djm 3888: if (fwd->listen_path != NULL) {
3889: return channel_cancel_lport_listener_streamlocal(ssh,
3890: fwd->listen_path);
3891: } else {
3892: return channel_cancel_lport_listener_tcpip(ssh,
3893: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3894: }
1.336 millert 3895: }
3896:
1.362 markus 3897: /* protocol local port fwd, used by ssh */
1.160 markus 3898: int
1.367 djm 3899: channel_setup_local_fwd_listener(struct ssh *ssh,
3900: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3901: {
1.336 millert 3902: if (fwd->listen_path != NULL) {
1.367 djm 3903: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3904: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3905: } else {
1.367 djm 3906: return channel_setup_fwd_listener_tcpip(ssh,
3907: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3908: }
1.160 markus 3909: }
3910:
1.381 djm 3911: /* Matches a remote forwarding permission against a requested forwarding */
3912: static int
3913: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
3914: {
3915: int ret;
3916: char *lhost;
3917:
3918: /* XXX add ACLs for streamlocal */
3919: if (fwd->listen_path != NULL)
3920: return 1;
3921:
3922: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
3923: return 0;
3924:
3925: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
3926: allowed_open->listen_port != fwd->listen_port)
3927: return 0;
3928:
3929: /* Match hostnames case-insensitively */
3930: lhost = xstrdup(fwd->listen_host);
3931: lowercase(lhost);
3932: ret = match_pattern(lhost, allowed_open->listen_host);
3933: free(lhost);
3934:
3935: return ret;
3936: }
3937:
3938: /* Checks whether a requested remote forwarding is permitted */
3939: static int
3940: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
3941: {
3942: struct ssh_channels *sc = ssh->chanctxt;
3943: struct permission_set *pset = &sc->remote_perms;
3944: u_int i, permit, permit_adm = 1;
3945: struct permission *perm;
3946:
3947: /* XXX apply GatewayPorts override before checking? */
3948:
3949: permit = pset->all_permitted;
3950: if (!permit) {
3951: for (i = 0; i < pset->num_permitted_user; i++) {
3952: perm = &pset->permitted_user[i];
3953: if (remote_open_match(perm, fwd)) {
3954: permit = 1;
3955: break;
3956: }
3957: }
3958: }
3959:
3960: if (pset->num_permitted_admin > 0) {
3961: permit_adm = 0;
3962: for (i = 0; i < pset->num_permitted_admin; i++) {
3963: perm = &pset->permitted_admin[i];
3964: if (remote_open_match(perm, fwd)) {
3965: permit_adm = 1;
3966: break;
3967: }
3968: }
3969: }
3970:
3971: return permit && permit_adm;
3972: }
3973:
1.160 markus 3974: /* protocol v2 remote port fwd, used by sshd */
3975: int
1.367 djm 3976: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3977: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3978: {
1.381 djm 3979: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 3980: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 3981: if (fwd->listen_path != NULL)
3982: /* XXX always allowed, see remote_open_match() */
3983: logit("Received request from %.100s port %d to "
3984: "remote forward to path \"%.100s\", "
3985: "but the request was denied.",
3986: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3987: fwd->listen_path);
3988: else if(fwd->listen_host != NULL)
3989: logit("Received request from %.100s port %d to "
3990: "remote forward to host %.100s port %d, "
3991: "but the request was denied.",
3992: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3993: fwd->listen_host, fwd->listen_port );
3994: else
3995: logit("Received request from %.100s port %d to remote "
3996: "forward, but the request was denied.",
3997: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 3998: return 0;
3999: }
1.336 millert 4000: if (fwd->listen_path != NULL) {
1.367 djm 4001: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 4002: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
4003: } else {
1.367 djm 4004: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 4005: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
4006: fwd_opts);
4007: }
1.160 markus 4008: }
4009:
1.27 markus 4010: /*
1.312 djm 4011: * Translate the requested rfwd listen host to something usable for
4012: * this server.
4013: */
4014: static const char *
4015: channel_rfwd_bind_host(const char *listen_host)
4016: {
4017: if (listen_host == NULL) {
1.378 djm 4018: return "localhost";
1.312 djm 4019: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 4020: return "";
1.312 djm 4021: } else
4022: return listen_host;
4023: }
4024:
4025: /*
1.27 markus 4026: * Initiate forwarding of connections to port "port" on remote host through
4027: * the secure channel to host:port from local side.
1.315 markus 4028: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 4029: * channel_update_permission().
1.27 markus 4030: */
1.253 markus 4031: int
1.367 djm 4032: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 4033: {
1.367 djm 4034: int r, success = 0, idx = -1;
4035: char *host_to_connect, *listen_host, *listen_path;
4036: int port_to_connect, listen_port;
1.73 markus 4037:
1.25 markus 4038: /* Send the forward request to the remote side. */
1.358 djm 4039: if (fwd->listen_path != NULL) {
1.367 djm 4040: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4041: (r = sshpkt_put_cstring(ssh,
4042: "streamlocal-forward@openssh.com")) != 0 ||
4043: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4044: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
4045: (r = sshpkt_send(ssh)) != 0 ||
4046: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4047: fatal_fr(r, "request streamlocal");
1.336 millert 4048: } else {
1.367 djm 4049: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4050: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
4051: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4052: (r = sshpkt_put_cstring(ssh,
4053: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
4054: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
4055: (r = sshpkt_send(ssh)) != 0 ||
4056: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4057: fatal_fr(r, "request tcpip-forward");
1.73 markus 4058: }
1.358 djm 4059: /* Assume that server accepts the request */
4060: success = 1;
1.73 markus 4061: if (success) {
1.305 djm 4062: /* Record that connection to this host/port is permitted. */
1.367 djm 4063: host_to_connect = listen_host = listen_path = NULL;
4064: port_to_connect = listen_port = 0;
1.336 millert 4065: if (fwd->connect_path != NULL) {
1.367 djm 4066: host_to_connect = xstrdup(fwd->connect_path);
4067: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 4068: } else {
1.367 djm 4069: host_to_connect = xstrdup(fwd->connect_host);
4070: port_to_connect = fwd->connect_port;
1.336 millert 4071: }
4072: if (fwd->listen_path != NULL) {
1.367 djm 4073: listen_path = xstrdup(fwd->listen_path);
4074: listen_port = PORT_STREAMLOCAL;
1.336 millert 4075: } else {
1.367 djm 4076: if (fwd->listen_host != NULL)
4077: listen_host = xstrdup(fwd->listen_host);
4078: listen_port = fwd->listen_port;
4079: }
1.381 djm 4080: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 4081: host_to_connect, port_to_connect,
4082: listen_host, listen_path, listen_port, NULL);
1.44 markus 4083: }
1.367 djm 4084: return idx;
1.1 deraadt 4085: }
4086:
1.333 markus 4087: static int
1.381 djm 4088: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 4089: int requestedport)
1.333 markus 4090: {
4091: if (allowed_open->host_to_connect == NULL)
4092: return 0;
4093: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
4094: allowed_open->port_to_connect != requestedport)
4095: return 0;
1.351 dtucker 4096: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
4097: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 4098: return 0;
4099: return 1;
4100: }
4101:
4102: /*
1.336 millert 4103: * Note that in the listen host/port case
1.333 markus 4104: * we don't support FWD_PERMIT_ANY_PORT and
4105: * need to translate between the configured-host (listen_host)
4106: * and what we've sent to the remote server (channel_rfwd_bind_host)
4107: */
4108: static int
1.381 djm 4109: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 4110: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 4111: {
4112: const char *allowed_host;
4113:
4114: if (allowed_open->host_to_connect == NULL)
4115: return 0;
4116: if (allowed_open->listen_port != requestedport)
4117: return 0;
1.335 djm 4118: if (!translate && allowed_open->listen_host == NULL &&
4119: requestedhost == NULL)
4120: return 1;
1.333 markus 4121: allowed_host = translate ?
4122: channel_rfwd_bind_host(allowed_open->listen_host) :
4123: allowed_open->listen_host;
1.382 djm 4124: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 4125: strcmp(allowed_host, requestedhost) != 0)
4126: return 0;
4127: return 1;
4128: }
4129:
1.336 millert 4130: static int
1.381 djm 4131: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 4132: const char *requestedpath)
4133: {
4134: if (allowed_open->host_to_connect == NULL)
4135: return 0;
4136: if (allowed_open->listen_port != PORT_STREAMLOCAL)
4137: return 0;
4138: if (allowed_open->listen_path == NULL ||
4139: strcmp(allowed_open->listen_path, requestedpath) != 0)
4140: return 0;
4141: return 1;
4142: }
4143:
1.27 markus 4144: /*
1.208 deraadt 4145: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 4146: * local side.
4147: */
1.336 millert 4148: static int
1.367 djm 4149: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
4150: const char *host, u_short port)
1.202 djm 4151: {
1.367 djm 4152: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4153: struct permission_set *pset = &sc->local_perms;
1.367 djm 4154: int r;
4155: u_int i;
1.397 markus 4156: struct permission *perm = NULL;
1.202 djm 4157:
1.381 djm 4158: for (i = 0; i < pset->num_permitted_user; i++) {
4159: perm = &pset->permitted_user[i];
4160: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 4161: break;
1.381 djm 4162: perm = NULL;
1.202 djm 4163: }
1.381 djm 4164: if (perm == NULL) {
1.403 djm 4165: debug_f("requested forward not found");
1.312 djm 4166: return -1;
1.202 djm 4167: }
1.367 djm 4168: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4169: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
4170: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4171: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
4172: (r = sshpkt_put_u32(ssh, port)) != 0 ||
4173: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4174: fatal_fr(r, "send cancel");
1.367 djm 4175:
1.381 djm 4176: fwd_perm_clear(perm); /* unregister */
1.336 millert 4177:
4178: return 0;
4179: }
4180:
4181: /*
4182: * Request cancellation of remote forwarding of Unix domain socket
4183: * path from local side.
4184: */
4185: static int
1.367 djm 4186: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 4187: {
1.367 djm 4188: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4189: struct permission_set *pset = &sc->local_perms;
1.367 djm 4190: int r;
4191: u_int i;
1.397 markus 4192: struct permission *perm = NULL;
1.336 millert 4193:
1.381 djm 4194: for (i = 0; i < pset->num_permitted_user; i++) {
4195: perm = &pset->permitted_user[i];
4196: if (open_listen_match_streamlocal(perm, path))
1.336 millert 4197: break;
1.381 djm 4198: perm = NULL;
1.336 millert 4199: }
1.381 djm 4200: if (perm == NULL) {
1.403 djm 4201: debug_f("requested forward not found");
1.336 millert 4202: return -1;
4203: }
1.367 djm 4204: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4205: (r = sshpkt_put_cstring(ssh,
4206: "cancel-streamlocal-forward@openssh.com")) != 0 ||
4207: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4208: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
4209: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4210: fatal_fr(r, "send cancel");
1.367 djm 4211:
1.381 djm 4212: fwd_perm_clear(perm); /* unregister */
1.312 djm 4213:
4214: return 0;
1.202 djm 4215: }
4216:
4217: /*
1.336 millert 4218: * Request cancellation of remote forwarding of a connection from local side.
4219: */
4220: int
1.367 djm 4221: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 4222: {
4223: if (fwd->listen_path != NULL) {
1.367 djm 4224: return channel_request_rforward_cancel_streamlocal(ssh,
4225: fwd->listen_path);
1.336 millert 4226: } else {
1.367 djm 4227: return channel_request_rforward_cancel_tcpip(ssh,
4228: fwd->listen_host,
4229: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 4230: }
1.1 deraadt 4231: }
4232:
1.99 markus 4233: /*
1.381 djm 4234: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 4235: * usually called by the server, because the user could connect to any port
4236: * anyway, and the server has no way to know but to trust the client anyway.
4237: */
4238: void
1.381 djm 4239: channel_permit_all(struct ssh *ssh, int where)
4240: {
4241: struct permission_set *pset = permission_set_get(ssh, where);
4242:
4243: if (pset->num_permitted_user == 0)
4244: pset->all_permitted = 1;
4245: }
4246:
4247: /*
4248: * Permit the specified host/port for forwarding.
4249: */
4250: void
4251: channel_add_permission(struct ssh *ssh, int who, int where,
4252: char *host, int port)
4253: {
4254: int local = where == FORWARD_LOCAL;
4255: struct permission_set *pset = permission_set_get(ssh, where);
4256:
4257: debug("allow %s forwarding to host %s port %d",
4258: fwd_ident(who, where), host, port);
4259: /*
4260: * Remote forwards set listen_host/port, local forwards set
4261: * host/port_to_connect.
4262: */
4263: permission_set_add(ssh, who, where,
4264: local ? host : 0, local ? port : 0,
4265: local ? NULL : host, NULL, local ? 0 : port, NULL);
4266: pset->all_permitted = 0;
4267: }
4268:
4269: /*
4270: * Administratively disable forwarding.
4271: */
4272: void
4273: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4274: {
1.381 djm 4275: channel_clear_permission(ssh, FORWARD_ADM, where);
4276: permission_set_add(ssh, FORWARD_ADM, where,
4277: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4278: }
4279:
1.381 djm 4280: /*
4281: * Clear a list of permitted opens.
4282: */
1.101 markus 4283: void
1.381 djm 4284: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4285: {
1.381 djm 4286: struct permission **permp;
4287: u_int *npermp;
1.367 djm 4288:
1.381 djm 4289: permission_set_get_array(ssh, who, where, &permp, &npermp);
4290: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4291: *npermp = 0;
1.315 markus 4292: }
4293:
4294: /*
4295: * Update the listen port for a dynamic remote forward, after
4296: * the actual 'newport' has been allocated. If 'newport' < 0 is
4297: * passed then they entry will be invalidated.
4298: */
4299: void
1.381 djm 4300: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4301: {
1.381 djm 4302: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4303:
1.381 djm 4304: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
1.403 djm 4305: debug_f("index out of range: %d num_permitted_user %d",
4306: idx, pset->num_permitted_user);
1.315 markus 4307: return;
4308: }
4309: debug("%s allowed port %d for forwarding to host %s port %d",
4310: newport > 0 ? "Updating" : "Removing",
4311: newport,
1.381 djm 4312: pset->permitted_user[idx].host_to_connect,
4313: pset->permitted_user[idx].port_to_connect);
1.367 djm 4314: if (newport <= 0)
1.381 djm 4315: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4316: else {
1.381 djm 4317: pset->permitted_user[idx].listen_port =
1.404 djm 4318: (ssh->compat & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
1.315 markus 4319: }
1.99 markus 4320: }
4321:
1.314 dtucker 4322: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4323: int
4324: permitopen_port(const char *p)
4325: {
4326: int port;
4327:
4328: if (strcmp(p, "*") == 0)
4329: return FWD_PERMIT_ANY_PORT;
4330: if ((port = a2port(p)) > 0)
4331: return port;
4332: return -1;
4333: }
4334:
1.276 djm 4335: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4336: static int
1.276 djm 4337: connect_next(struct channel_connect *cctx)
1.41 markus 4338: {
1.276 djm 4339: int sock, saved_errno;
1.336 millert 4340: struct sockaddr_un *sunaddr;
1.367 djm 4341: char ntop[NI_MAXHOST];
4342: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4343:
1.276 djm 4344: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4345: switch (cctx->ai->ai_family) {
4346: case AF_UNIX:
4347: /* unix:pathname instead of host:port */
4348: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4349: strlcpy(ntop, "unix", sizeof(ntop));
4350: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4351: break;
4352: case AF_INET:
4353: case AF_INET6:
4354: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4355: ntop, sizeof(ntop), strport, sizeof(strport),
4356: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
4357: error("connect_next: getnameinfo failed");
4358: continue;
4359: }
4360: break;
4361: default:
1.41 markus 4362: continue;
4363: }
1.300 dtucker 4364: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4365: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4366: if (cctx->ai->ai_next == NULL)
1.186 djm 4367: error("socket: %.100s", strerror(errno));
4368: else
4369: verbose("socket: %.100s", strerror(errno));
1.41 markus 4370: continue;
4371: }
1.205 djm 4372: if (set_nonblock(sock) == -1)
1.403 djm 4373: fatal_f("set_nonblock(%d)", sock);
1.276 djm 4374: if (connect(sock, cctx->ai->ai_addr,
4375: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
4376: debug("connect_next: host %.100s ([%.100s]:%s): "
4377: "%.100s", cctx->host, ntop, strport,
1.41 markus 4378: strerror(errno));
1.276 djm 4379: saved_errno = errno;
1.41 markus 4380: close(sock);
1.276 djm 4381: errno = saved_errno;
1.89 stevesk 4382: continue; /* fail -- try next */
1.41 markus 4383: }
1.336 millert 4384: if (cctx->ai->ai_family != AF_UNIX)
4385: set_nodelay(sock);
1.276 djm 4386: debug("connect_next: host %.100s ([%.100s]:%s) "
4387: "in progress, fd=%d", cctx->host, ntop, strport, sock);
4388: cctx->ai = cctx->ai->ai_next;
4389: return sock;
4390: }
4391: return -1;
4392: }
1.41 markus 4393:
1.276 djm 4394: static void
4395: channel_connect_ctx_free(struct channel_connect *cctx)
4396: {
1.321 djm 4397: free(cctx->host);
1.336 millert 4398: if (cctx->aitop) {
4399: if (cctx->aitop->ai_family == AF_UNIX)
4400: free(cctx->aitop);
4401: else
4402: freeaddrinfo(cctx->aitop);
4403: }
1.329 tedu 4404: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4405: }
4406:
1.357 dtucker 4407: /*
1.372 markus 4408: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4409: * passing back the failure reason if appropriate.
4410: */
1.372 markus 4411: static int
4412: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4413: char *ctype, char *rname, struct channel_connect *cctx,
4414: int *reason, const char **errmsg)
1.276 djm 4415: {
4416: struct addrinfo hints;
4417: int gaierr;
4418: int sock = -1;
4419: char strport[NI_MAXSERV];
1.336 millert 4420:
4421: if (port == PORT_STREAMLOCAL) {
4422: struct sockaddr_un *sunaddr;
4423: struct addrinfo *ai;
4424:
4425: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4426: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4427: return -1;
1.336 millert 4428: }
4429:
4430: /*
4431: * Fake up a struct addrinfo for AF_UNIX connections.
4432: * channel_connect_ctx_free() must check ai_family
4433: * and use free() not freeaddirinfo() for AF_UNIX.
4434: */
4435: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4436: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4437: ai->ai_addr = (struct sockaddr *)(ai + 1);
4438: ai->ai_addrlen = sizeof(*sunaddr);
4439: ai->ai_family = AF_UNIX;
1.372 markus 4440: ai->ai_socktype = socktype;
1.336 millert 4441: ai->ai_protocol = PF_UNSPEC;
4442: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4443: sunaddr->sun_family = AF_UNIX;
4444: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4445: cctx->aitop = ai;
1.336 millert 4446: } else {
4447: memset(&hints, 0, sizeof(hints));
1.367 djm 4448: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4449: hints.ai_socktype = socktype;
1.336 millert 4450: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4451: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4452: != 0) {
4453: if (errmsg != NULL)
4454: *errmsg = ssh_gai_strerror(gaierr);
4455: if (reason != NULL)
4456: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4457: error("connect_to %.100s: unknown host (%s)", name,
4458: ssh_gai_strerror(gaierr));
1.372 markus 4459: return -1;
1.336 millert 4460: }
1.41 markus 4461: }
1.276 djm 4462:
1.372 markus 4463: cctx->host = xstrdup(name);
4464: cctx->port = port;
4465: cctx->ai = cctx->aitop;
1.276 djm 4466:
1.372 markus 4467: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4468: error("connect to %.100s port %d failed: %s",
1.336 millert 4469: name, port, strerror(errno));
1.372 markus 4470: return -1;
4471: }
4472:
4473: return sock;
4474: }
4475:
4476: /* Return CONNECTING channel to remote host:port or local socket path */
4477: static Channel *
4478: connect_to(struct ssh *ssh, const char *host, int port,
4479: char *ctype, char *rname)
4480: {
4481: struct channel_connect cctx;
4482: Channel *c;
4483: int sock;
4484:
4485: memset(&cctx, 0, sizeof(cctx));
4486: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4487: &cctx, NULL, NULL);
4488: if (sock == -1) {
1.276 djm 4489: channel_connect_ctx_free(&cctx);
4490: return NULL;
1.41 markus 4491: }
1.367 djm 4492: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4493: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4494: c->host_port = port;
4495: c->path = xstrdup(host);
1.276 djm 4496: c->connect_ctx = cctx;
1.372 markus 4497:
1.276 djm 4498: return c;
1.41 markus 4499: }
1.99 markus 4500:
1.354 markus 4501: /*
4502: * returns either the newly connected channel or the downstream channel
4503: * that needs to deal with this connection.
4504: */
1.276 djm 4505: Channel *
1.367 djm 4506: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4507: u_short listen_port, char *ctype, char *rname)
1.73 markus 4508: {
1.367 djm 4509: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4510: struct permission_set *pset = &sc->local_perms;
1.367 djm 4511: u_int i;
1.381 djm 4512: struct permission *perm;
1.99 markus 4513:
1.381 djm 4514: for (i = 0; i < pset->num_permitted_user; i++) {
4515: perm = &pset->permitted_user[i];
4516: if (open_listen_match_tcpip(perm,
4517: listen_host, listen_port, 1)) {
4518: if (perm->downstream)
4519: return perm->downstream;
4520: if (perm->port_to_connect == 0)
1.372 markus 4521: return rdynamic_connect_prepare(ssh,
4522: ctype, rname);
1.367 djm 4523: return connect_to(ssh,
1.381 djm 4524: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4525: ctype, rname);
1.276 djm 4526: }
4527: }
1.74 markus 4528: error("WARNING: Server requests forwarding for unknown listen_port %d",
4529: listen_port);
1.276 djm 4530: return NULL;
1.73 markus 4531: }
4532:
1.336 millert 4533: Channel *
1.367 djm 4534: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4535: char *ctype, char *rname)
1.336 millert 4536: {
1.367 djm 4537: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4538: struct permission_set *pset = &sc->local_perms;
1.367 djm 4539: u_int i;
1.381 djm 4540: struct permission *perm;
1.336 millert 4541:
1.381 djm 4542: for (i = 0; i < pset->num_permitted_user; i++) {
4543: perm = &pset->permitted_user[i];
4544: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4545: return connect_to(ssh,
1.381 djm 4546: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4547: ctype, rname);
1.336 millert 4548: }
4549: }
4550: error("WARNING: Server requests forwarding for unknown path %.100s",
4551: path);
4552: return NULL;
4553: }
4554:
1.99 markus 4555: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4556: Channel *
1.367 djm 4557: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4558: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4559: {
1.367 djm 4560: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4561: struct permission_set *pset = &sc->local_perms;
1.372 markus 4562: struct channel_connect cctx;
4563: Channel *c;
1.367 djm 4564: u_int i, permit, permit_adm = 1;
1.372 markus 4565: int sock;
1.381 djm 4566: struct permission *perm;
1.99 markus 4567:
1.381 djm 4568: permit = pset->all_permitted;
1.99 markus 4569: if (!permit) {
1.381 djm 4570: for (i = 0; i < pset->num_permitted_user; i++) {
4571: perm = &pset->permitted_user[i];
4572: if (open_match(perm, host, port)) {
1.99 markus 4573: permit = 1;
1.333 markus 4574: break;
4575: }
1.367 djm 4576: }
1.257 dtucker 4577: }
1.99 markus 4578:
1.381 djm 4579: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4580: permit_adm = 0;
1.381 djm 4581: for (i = 0; i < pset->num_permitted_admin; i++) {
4582: perm = &pset->permitted_admin[i];
4583: if (open_match(perm, host, port)) {
1.257 dtucker 4584: permit_adm = 1;
1.333 markus 4585: break;
4586: }
1.367 djm 4587: }
1.99 markus 4588: }
1.257 dtucker 4589:
4590: if (!permit || !permit_adm) {
1.391 florian 4591: logit("Received request from %.100s port %d to connect to "
4592: "host %.100s port %d, but the request was denied.",
4593: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4594: if (reason != NULL)
4595: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4596: return NULL;
1.99 markus 4597: }
1.372 markus 4598:
4599: memset(&cctx, 0, sizeof(cctx));
4600: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4601: &cctx, reason, errmsg);
4602: if (sock == -1) {
4603: channel_connect_ctx_free(&cctx);
4604: return NULL;
4605: }
4606:
4607: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4608: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4609: c->host_port = port;
4610: c->path = xstrdup(host);
4611: c->connect_ctx = cctx;
4612:
4613: return c;
1.336 millert 4614: }
4615:
4616: /* Check if connecting to that path is permitted and connect. */
4617: Channel *
1.367 djm 4618: channel_connect_to_path(struct ssh *ssh, const char *path,
4619: char *ctype, char *rname)
1.336 millert 4620: {
1.367 djm 4621: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4622: struct permission_set *pset = &sc->local_perms;
1.367 djm 4623: u_int i, permit, permit_adm = 1;
1.381 djm 4624: struct permission *perm;
1.336 millert 4625:
1.381 djm 4626: permit = pset->all_permitted;
1.336 millert 4627: if (!permit) {
1.381 djm 4628: for (i = 0; i < pset->num_permitted_user; i++) {
4629: perm = &pset->permitted_user[i];
4630: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4631: permit = 1;
4632: break;
4633: }
1.367 djm 4634: }
1.336 millert 4635: }
4636:
1.381 djm 4637: if (pset->num_permitted_admin > 0) {
1.336 millert 4638: permit_adm = 0;
1.381 djm 4639: for (i = 0; i < pset->num_permitted_admin; i++) {
4640: perm = &pset->permitted_admin[i];
4641: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4642: permit_adm = 1;
4643: break;
4644: }
1.367 djm 4645: }
1.336 millert 4646: }
4647:
4648: if (!permit || !permit_adm) {
4649: logit("Received request to connect to path %.100s, "
4650: "but the request was denied.", path);
4651: return NULL;
4652: }
1.367 djm 4653: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4654: }
4655:
4656: void
1.367 djm 4657: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4658: {
1.367 djm 4659: struct ssh_channels *sc = ssh->chanctxt;
4660: struct winsize ws;
4661: int r;
1.209 avsm 4662: u_int i;
1.204 djm 4663:
1.367 djm 4664: for (i = 0; i < sc->channels_alloc; i++) {
4665: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4666: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4667: continue;
1.393 deraadt 4668: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4669: continue;
1.367 djm 4670: channel_request_start(ssh, i, "window-change", 0);
4671: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4672: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4673: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4674: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4675: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4676: fatal_fr(r, "channel %u; send window-change", i);
1.204 djm 4677: }
1.372 markus 4678: }
4679:
4680: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4681: static Channel *
4682: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4683: {
4684: Channel *c;
4685: int r;
4686:
4687: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4688: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4689: c->host_port = 0;
4690: c->path = NULL;
4691:
4692: /*
4693: * We need to open the channel before we have a FD,
4694: * so that we can get SOCKS header from peer.
4695: */
4696: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4697: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4698: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4699: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 4700: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0)
4701: fatal_fr(r, "channel %i; confirm", c->self);
1.372 markus 4702: return c;
4703: }
4704:
4705: /* Return CONNECTING socket to remote host:port or local socket path */
4706: static int
4707: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4708: {
1.405 markus 4709: struct ssh_channels *sc = ssh->chanctxt;
4710: struct permission_set *pset = &sc->local_perms;
4711: struct permission *perm;
1.372 markus 4712: struct channel_connect cctx;
1.405 markus 4713: u_int i, permit_adm = 1;
1.372 markus 4714: int sock;
1.405 markus 4715:
4716: if (pset->num_permitted_admin > 0) {
4717: permit_adm = 0;
4718: for (i = 0; i < pset->num_permitted_admin; i++) {
4719: perm = &pset->permitted_admin[i];
4720: if (open_match(perm, c->path, c->host_port)) {
4721: permit_adm = 1;
4722: break;
4723: }
4724: }
4725: }
4726: if (!permit_adm) {
4727: debug_f("requested forward not permitted");
4728: return -1;
4729: }
1.372 markus 4730:
4731: memset(&cctx, 0, sizeof(cctx));
4732: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4733: NULL, &cctx, NULL, NULL);
4734: if (sock == -1)
4735: channel_connect_ctx_free(&cctx);
4736: else {
4737: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4738: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4739: c->connect_ctx = cctx;
4740: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4741: }
4742: return sock;
1.99 markus 4743: }
4744:
1.121 markus 4745: /* -- X11 forwarding */
1.1 deraadt 4746:
1.27 markus 4747: /*
4748: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4749: * Returns 0 and a suitable display number for the DISPLAY variable
4750: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4751: */
1.141 stevesk 4752: int
1.367 djm 4753: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4754: int x11_use_localhost, int single_connection,
4755: u_int *display_numberp, int **chanids)
1.1 deraadt 4756: {
1.149 markus 4757: Channel *nc = NULL;
1.31 markus 4758: int display_number, sock;
4759: u_short port;
1.35 markus 4760: struct addrinfo hints, *ai, *aitop;
4761: char strport[NI_MAXSERV];
4762: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4763:
1.224 markus 4764: if (chanids == NULL)
4765: return -1;
4766:
1.33 markus 4767: for (display_number = x11_display_offset;
1.148 deraadt 4768: display_number < MAX_DISPLAYS;
4769: display_number++) {
1.25 markus 4770: port = 6000 + display_number;
1.35 markus 4771: memset(&hints, 0, sizeof(hints));
1.367 djm 4772: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4773: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4774: hints.ai_socktype = SOCK_STREAM;
4775: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4776: if ((gaierr = getaddrinfo(NULL, strport,
4777: &hints, &aitop)) != 0) {
1.271 dtucker 4778: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4779: return -1;
1.25 markus 4780: }
1.35 markus 4781: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4782: if (ai->ai_family != AF_INET &&
4783: ai->ai_family != AF_INET6)
1.35 markus 4784: continue;
1.300 dtucker 4785: sock = socket(ai->ai_family, ai->ai_socktype,
4786: ai->ai_protocol);
1.393 deraadt 4787: if (sock == -1) {
1.35 markus 4788: error("socket: %.100s", strerror(errno));
1.203 markus 4789: freeaddrinfo(aitop);
1.141 stevesk 4790: return -1;
1.35 markus 4791: }
1.376 djm 4792: set_reuseaddr(sock);
1.393 deraadt 4793: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.403 djm 4794: debug2_f("bind port %d: %.100s", port,
4795: strerror(errno));
1.35 markus 4796: close(sock);
1.367 djm 4797: for (n = 0; n < num_socks; n++)
1.35 markus 4798: close(socks[n]);
4799: num_socks = 0;
4800: break;
4801: }
4802: socks[num_socks++] = sock;
4803: if (num_socks == NUM_SOCKS)
4804: break;
1.25 markus 4805: }
1.83 stevesk 4806: freeaddrinfo(aitop);
1.35 markus 4807: if (num_socks > 0)
4808: break;
1.25 markus 4809: }
4810: if (display_number >= MAX_DISPLAYS) {
4811: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4812: return -1;
1.25 markus 4813: }
4814: /* Start listening for connections on the socket. */
1.35 markus 4815: for (n = 0; n < num_socks; n++) {
4816: sock = socks[n];
1.393 deraadt 4817: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 4818: error("listen: %.100s", strerror(errno));
4819: close(sock);
1.141 stevesk 4820: return -1;
1.35 markus 4821: }
1.25 markus 4822: }
1.35 markus 4823:
4824: /* Allocate a channel for each socket. */
1.242 djm 4825: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4826: for (n = 0; n < num_socks; n++) {
4827: sock = socks[n];
1.367 djm 4828: nc = channel_new(ssh, "x11 listener",
1.51 markus 4829: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4830: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4831: 0, "X11 inet listener", 1);
1.167 markus 4832: nc->single_connection = single_connection;
1.224 markus 4833: (*chanids)[n] = nc->self;
1.35 markus 4834: }
1.224 markus 4835: (*chanids)[n] = -1;
1.1 deraadt 4836:
1.141 stevesk 4837: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4838: *display_numberp = display_number;
1.367 djm 4839: return 0;
1.1 deraadt 4840: }
4841:
1.127 itojun 4842: static int
1.77 markus 4843: connect_local_xsocket(u_int dnr)
1.1 deraadt 4844: {
1.25 markus 4845: int sock;
4846: struct sockaddr_un addr;
4847:
1.147 stevesk 4848: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 deraadt 4849: if (sock == -1)
1.147 stevesk 4850: error("socket: %.100s", strerror(errno));
4851: memset(&addr, 0, sizeof(addr));
4852: addr.sun_family = AF_UNIX;
4853: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4854: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4855: return sock;
4856: close(sock);
1.25 markus 4857: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4858: return -1;
1.1 deraadt 4859: }
4860:
1.51 markus 4861: int
1.367 djm 4862: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4863: {
1.248 deraadt 4864: u_int display_number;
1.25 markus 4865: const char *display;
1.51 markus 4866: char buf[1024], *cp;
1.35 markus 4867: struct addrinfo hints, *ai, *aitop;
4868: char strport[NI_MAXSERV];
1.248 deraadt 4869: int gaierr, sock = 0;
1.25 markus 4870:
4871: /* Try to open a socket for the local X server. */
4872: display = getenv("DISPLAY");
4873: if (!display) {
4874: error("DISPLAY not set.");
1.51 markus 4875: return -1;
1.25 markus 4876: }
1.27 markus 4877: /*
4878: * Now we decode the value of the DISPLAY variable and make a
4879: * connection to the real X server.
4880: */
4881:
4882: /*
4883: * Check if it is a unix domain socket. Unix domain displays are in
4884: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4885: */
1.25 markus 4886: if (strncmp(display, "unix:", 5) == 0 ||
4887: display[0] == ':') {
4888: /* Connect to the unix domain socket. */
1.367 djm 4889: if (sscanf(strrchr(display, ':') + 1, "%u",
4890: &display_number) != 1) {
4891: error("Could not parse display number from DISPLAY: "
4892: "%.100s", display);
1.51 markus 4893: return -1;
1.25 markus 4894: }
4895: /* Create a socket. */
4896: sock = connect_local_xsocket(display_number);
4897: if (sock < 0)
1.51 markus 4898: return -1;
1.25 markus 4899:
4900: /* OK, we now have a connection to the display. */
1.51 markus 4901: return sock;
1.25 markus 4902: }
1.27 markus 4903: /*
4904: * Connect to an inet socket. The DISPLAY value is supposedly
4905: * hostname:d[.s], where hostname may also be numeric IP address.
4906: */
1.145 stevesk 4907: strlcpy(buf, display, sizeof(buf));
1.25 markus 4908: cp = strchr(buf, ':');
4909: if (!cp) {
4910: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4911: return -1;
1.25 markus 4912: }
4913: *cp = 0;
1.367 djm 4914: /*
4915: * buf now contains the host name. But first we parse the
4916: * display number.
4917: */
1.248 deraadt 4918: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4919: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4920: display);
1.51 markus 4921: return -1;
1.25 markus 4922: }
1.35 markus 4923:
4924: /* Look up the host address */
4925: memset(&hints, 0, sizeof(hints));
1.367 djm 4926: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4927: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4928: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4929: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4930: error("%.100s: unknown host. (%s)", buf,
4931: ssh_gai_strerror(gaierr));
1.51 markus 4932: return -1;
1.25 markus 4933: }
1.35 markus 4934: for (ai = aitop; ai; ai = ai->ai_next) {
4935: /* Create a socket. */
1.300 dtucker 4936: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 4937: if (sock == -1) {
1.194 markus 4938: debug2("socket: %.100s", strerror(errno));
1.41 markus 4939: continue;
4940: }
4941: /* Connect it to the display. */
1.393 deraadt 4942: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 4943: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4944: 6000 + display_number, strerror(errno));
4945: close(sock);
4946: continue;
4947: }
4948: /* Success */
4949: break;
1.35 markus 4950: }
4951: freeaddrinfo(aitop);
4952: if (!ai) {
1.367 djm 4953: error("connect %.100s port %u: %.100s", buf,
4954: 6000 + display_number, strerror(errno));
1.51 markus 4955: return -1;
1.25 markus 4956: }
1.162 stevesk 4957: set_nodelay(sock);
1.51 markus 4958: return sock;
4959: }
4960:
4961: /*
1.27 markus 4962: * Requests forwarding of X11 connections, generates fake authentication
4963: * data, and enables authentication spoofing.
1.121 markus 4964: * This should be called in the client only.
1.27 markus 4965: */
1.49 markus 4966: void
1.367 djm 4967: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4968: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4969: {
1.367 djm 4970: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4971: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4972: u_int i, value;
1.367 djm 4973: const char *cp;
1.25 markus 4974: char *new_data;
1.367 djm 4975: int r, screen_number;
1.25 markus 4976:
1.367 djm 4977: if (sc->x11_saved_display == NULL)
4978: sc->x11_saved_display = xstrdup(disp);
4979: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4980: error("x11_request_forwarding_with_spoofing: different "
4981: "$DISPLAY already forwarded");
4982: return;
4983: }
4984:
1.266 djm 4985: cp = strchr(disp, ':');
1.25 markus 4986: if (cp)
4987: cp = strchr(cp, '.');
4988: if (cp)
1.245 deraadt 4989: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4990: else
4991: screen_number = 0;
4992:
1.367 djm 4993: if (sc->x11_saved_proto == NULL) {
1.219 djm 4994: /* Save protocol name. */
1.367 djm 4995: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4996:
4997: /* Extract real authentication data. */
1.367 djm 4998: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4999: for (i = 0; i < data_len; i++) {
1.403 djm 5000: if (sscanf(data + 2 * i, "%2x", &value) != 1) {
1.219 djm 5001: fatal("x11_request_forwarding: bad "
5002: "authentication data: %.100s", data);
1.403 djm 5003: }
1.367 djm 5004: sc->x11_saved_data[i] = value;
1.219 djm 5005: }
1.367 djm 5006: sc->x11_saved_data_len = data_len;
1.353 natano 5007:
5008: /* Generate fake data of the same length. */
1.367 djm 5009: sc->x11_fake_data = xmalloc(data_len);
5010: arc4random_buf(sc->x11_fake_data, data_len);
5011: sc->x11_fake_data_len = data_len;
1.25 markus 5012: }
5013:
5014: /* Convert the fake data into hex. */
1.367 djm 5015: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 5016:
5017: /* Send the request packet. */
1.367 djm 5018: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
5019: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
5020: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
5021: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
5022: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
5023: (r = sshpkt_send(ssh)) != 0 ||
5024: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 5025: fatal_fr(r, "send x11-req");
1.321 djm 5026: free(new_data);
1.1 deraadt 5027: }
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