Annotation of src/usr.bin/ssh/channels.c, Revision 1.407
1.407 ! djm 1: /* $OpenBSD: channels.c,v 1.406 2021/04/03 06:18:40 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>
1.367 djm 57: #include <stdarg.h>
1.341 millert 58: #include <stdint.h>
1.263 stevesk 59: #include <stdio.h>
1.262 stevesk 60: #include <stdlib.h>
1.260 stevesk 61: #include <string.h>
1.233 stevesk 62: #include <termios.h>
1.256 stevesk 63: #include <unistd.h>
1.1 deraadt 64:
1.265 deraadt 65: #include "xmalloc.h"
1.1 deraadt 66: #include "ssh.h"
1.82 markus 67: #include "ssh2.h"
1.354 markus 68: #include "ssherr.h"
1.367 djm 69: #include "sshbuf.h"
1.1 deraadt 70: #include "packet.h"
1.82 markus 71: #include "log.h"
72: #include "misc.h"
1.14 markus 73: #include "channels.h"
74: #include "compat.h"
1.82 markus 75: #include "canohost.h"
1.383 markus 76: #include "sshkey.h"
1.64 markus 77: #include "authfd.h"
1.147 stevesk 78: #include "pathnames.h"
1.381 djm 79: #include "match.h"
1.388 djm 80:
1.367 djm 81: /* -- agent forwarding */
82: #define NUM_SOCKS 10
1.12 markus 83:
1.367 djm 84: /* -- tcp forwarding */
85: /* special-case port number meaning allow any port */
86: #define FWD_PERMIT_ANY_PORT 0
1.1 deraadt 87:
1.367 djm 88: /* special-case wildcard meaning allow any host */
89: #define FWD_PERMIT_ANY_HOST "*"
1.1 deraadt 90:
1.367 djm 91: /* -- X11 forwarding */
92: /* Maximum number of fake X11 displays to try. */
93: #define MAX_DISPLAYS 1000
1.1 deraadt 94:
1.381 djm 95: /* Per-channel callback for pre/post select() actions */
96: typedef void chan_fn(struct ssh *, Channel *c,
97: fd_set *readset, fd_set *writeset);
98:
1.27 markus 99: /*
100: * Data structure for storing which hosts are permitted for forward requests.
101: * The local sides of any remote forwards are stored in this array to prevent
102: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
103: * network (which might be behind a firewall).
104: */
1.336 millert 105: /* XXX: streamlocal wants a path instead of host:port */
106: /* Overload host_to_connect; we could just make this match Forward */
107: /* XXX - can we use listen_host instead of listen_path? */
1.381 djm 108: struct permission {
1.41 markus 109: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 110: int port_to_connect; /* Connect to 'port'. */
1.333 markus 111: char *listen_host; /* Remote side should listen address. */
1.336 millert 112: char *listen_path; /* Remote side should listen path. */
113: int listen_port; /* Remote side should listen port. */
1.354 markus 114: Channel *downstream; /* Downstream mux*/
1.381 djm 115: };
116:
117: /*
118: * Stores the forwarding permission state for a single direction (local or
119: * remote).
120: */
121: struct permission_set {
122: /*
123: * List of all local permitted host/port pairs to allow for the
124: * user.
125: */
126: u_int num_permitted_user;
127: struct permission *permitted_user;
1.1 deraadt 128:
1.381 djm 129: /*
130: * List of all permitted host/port pairs to allow for the admin.
131: */
132: u_int num_permitted_admin;
133: struct permission *permitted_admin;
134:
135: /*
136: * If this is true, all opens/listens are permitted. This is the
137: * case on the server on which we have to trust the client anyway,
138: * and the user could do anything after logging in.
139: */
140: int all_permitted;
141: };
1.121 markus 142:
1.367 djm 143: /* Master structure for channels state */
144: struct ssh_channels {
145: /*
146: * Pointer to an array containing all allocated channels. The array
147: * is dynamically extended as needed.
148: */
149: Channel **channels;
1.257 dtucker 150:
1.367 djm 151: /*
152: * Size of the channel array. All slots of the array must always be
153: * initialized (at least the type field); unused slots set to NULL
154: */
155: u_int channels_alloc;
1.257 dtucker 156:
1.367 djm 157: /*
158: * Maximum file descriptor value used in any of the channels. This is
159: * updated in channel_new.
160: */
161: int channel_max_fd;
1.257 dtucker 162:
1.367 djm 163: /*
164: * 'channel_pre*' are called just before select() to add any bits
165: * relevant to channels in the select bitmasks.
166: *
167: * 'channel_post*': perform any appropriate operations for
168: * channels which have events pending.
169: */
170: chan_fn **channel_pre;
171: chan_fn **channel_post;
1.314 dtucker 172:
1.367 djm 173: /* -- tcp forwarding */
1.381 djm 174: struct permission_set local_perms;
175: struct permission_set remote_perms;
1.219 djm 176:
1.367 djm 177: /* -- X11 forwarding */
1.121 markus 178:
1.367 djm 179: /* Saved X11 local (client) display. */
180: char *x11_saved_display;
1.121 markus 181:
1.367 djm 182: /* Saved X11 authentication protocol name. */
183: char *x11_saved_proto;
1.347 djm 184:
1.367 djm 185: /* Saved X11 authentication data. This is the real data. */
186: char *x11_saved_data;
187: u_int x11_saved_data_len;
1.121 markus 188:
1.367 djm 189: /* Deadline after which all X11 connections are refused */
190: u_int x11_refuse_time;
1.121 markus 191:
1.367 djm 192: /*
193: * Fake X11 authentication data. This is what the server will be
194: * sending us; we should replace any occurrences of this by the
195: * real data.
196: */
197: u_char *x11_fake_data;
198: u_int x11_fake_data_len;
1.121 markus 199:
1.367 djm 200: /* AF_UNSPEC or AF_INET or AF_INET6 */
201: int IPv4or6;
202: };
1.1 deraadt 203:
1.121 markus 204: /* helper */
1.367 djm 205: static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
1.354 markus 206: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 207:
1.276 djm 208: /* non-blocking connect helpers */
209: static int connect_next(struct channel_connect *);
210: static void channel_connect_ctx_free(struct channel_connect *);
1.372 markus 211: static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
212: static int rdynamic_connect_finish(struct ssh *, Channel *);
1.276 djm 213:
1.367 djm 214: /* Setup helper */
215: static void channel_handler_init(struct ssh_channels *sc);
216:
1.121 markus 217: /* -- channel core */
1.41 markus 218:
1.367 djm 219: void
220: channel_init_channels(struct ssh *ssh)
221: {
222: struct ssh_channels *sc;
223:
1.387 djm 224: if ((sc = calloc(1, sizeof(*sc))) == NULL)
1.403 djm 225: fatal_f("allocation failed");
1.367 djm 226: sc->channels_alloc = 10;
227: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
228: sc->IPv4or6 = AF_UNSPEC;
229: channel_handler_init(sc);
230:
231: ssh->chanctxt = sc;
232: }
233:
1.41 markus 234: Channel *
1.367 djm 235: channel_by_id(struct ssh *ssh, int id)
1.41 markus 236: {
237: Channel *c;
1.113 markus 238:
1.367 djm 239: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
1.403 djm 240: logit_f("%d: bad id", id);
1.41 markus 241: return NULL;
242: }
1.367 djm 243: c = ssh->chanctxt->channels[id];
1.113 markus 244: if (c == NULL) {
1.403 djm 245: logit_f("%d: bad id: channel free", id);
1.41 markus 246: return NULL;
247: }
248: return c;
1.55 markus 249: }
250:
1.354 markus 251: Channel *
1.368 djm 252: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 253: {
254: Channel *c;
255: u_int i;
256:
1.367 djm 257: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
258: c = ssh->chanctxt->channels[i];
1.368 djm 259: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 260: return c;
261: }
262: return NULL;
263: }
264:
1.27 markus 265: /*
1.229 markus 266: * Returns the channel if it is allowed to receive protocol messages.
267: * Private channels, like listening sockets, may not receive messages.
268: */
269: Channel *
1.367 djm 270: channel_lookup(struct ssh *ssh, int id)
1.229 markus 271: {
272: Channel *c;
273:
1.367 djm 274: if ((c = channel_by_id(ssh, id)) == NULL)
275: return NULL;
1.229 markus 276:
1.237 deraadt 277: switch (c->type) {
1.229 markus 278: case SSH_CHANNEL_X11_OPEN:
279: case SSH_CHANNEL_LARVAL:
280: case SSH_CHANNEL_CONNECTING:
281: case SSH_CHANNEL_DYNAMIC:
1.372 markus 282: case SSH_CHANNEL_RDYNAMIC_OPEN:
283: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 284: case SSH_CHANNEL_OPENING:
285: case SSH_CHANNEL_OPEN:
1.323 dtucker 286: case SSH_CHANNEL_ABANDONED:
1.354 markus 287: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 288: return c;
1.229 markus 289: }
290: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 291: return NULL;
1.229 markus 292: }
293:
294: /*
1.55 markus 295: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 296: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 297: */
1.127 itojun 298: static void
1.367 djm 299: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 300: int extusage, int nonblock, int is_tty)
1.1 deraadt 301: {
1.367 djm 302: struct ssh_channels *sc = ssh->chanctxt;
303:
1.25 markus 304: /* Update the maximum file descriptor value. */
1.367 djm 305: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, rfd);
306: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, wfd);
307: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, efd);
1.84 markus 308:
1.298 dtucker 309: if (rfd != -1)
310: fcntl(rfd, F_SETFD, FD_CLOEXEC);
311: if (wfd != -1 && wfd != rfd)
312: fcntl(wfd, F_SETFD, FD_CLOEXEC);
313: if (efd != -1 && efd != rfd && efd != wfd)
314: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 315:
1.52 markus 316: c->rfd = rfd;
317: c->wfd = wfd;
318: c->sock = (rfd == wfd) ? rfd : -1;
319: c->efd = efd;
320: c->extended_usage = extusage;
1.71 markus 321:
1.282 dtucker 322: if ((c->isatty = is_tty) != 0)
1.194 markus 323: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 324:
1.71 markus 325: /* enable nonblocking mode */
1.407 ! djm 326: c->restore_block = 0;
! 327: if (nonblock == CHANNEL_NONBLOCK_STDIO) {
! 328: /*
! 329: * Special handling for stdio file descriptors: do not set
! 330: * non-blocking mode if they are TTYs. Otherwise prepare to
! 331: * restore their blocking state on exit to avoid interfering
! 332: * with other programs that follow.
! 333: */
! 334: if (rfd != -1 && !isatty(rfd) && fcntl(rfd, F_GETFL) == 0) {
! 335: c->restore_block |= CHANNEL_RESTORE_RFD;
! 336: set_nonblock(rfd);
! 337: }
! 338: if (wfd != -1 && !isatty(wfd) && fcntl(wfd, F_GETFL) == 0) {
! 339: c->restore_block |= CHANNEL_RESTORE_WFD;
! 340: set_nonblock(wfd);
! 341: }
! 342: if (efd != -1 && !isatty(efd) && fcntl(efd, F_GETFL) == 0) {
! 343: c->restore_block |= CHANNEL_RESTORE_EFD;
! 344: set_nonblock(efd);
! 345: }
! 346: } else if (nonblock) {
1.71 markus 347: if (rfd != -1)
348: set_nonblock(rfd);
349: if (wfd != -1)
350: set_nonblock(wfd);
351: if (efd != -1)
352: set_nonblock(efd);
353: }
1.52 markus 354: }
355:
356: /*
357: * Allocate a new channel object and set its type and socket. This will cause
358: * remote_name to be freed.
359: */
1.113 markus 360: Channel *
1.367 djm 361: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 362: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 363: {
1.367 djm 364: struct ssh_channels *sc = ssh->chanctxt;
365: u_int i, found;
1.52 markus 366: Channel *c;
1.402 djm 367: int r;
1.25 markus 368:
369: /* Try to find a free slot where to put the new channel. */
1.367 djm 370: for (i = 0; i < sc->channels_alloc; i++) {
371: if (sc->channels[i] == NULL) {
1.25 markus 372: /* Found a free slot. */
1.367 djm 373: found = i;
1.25 markus 374: break;
375: }
1.367 djm 376: }
377: if (i >= sc->channels_alloc) {
378: /*
379: * There are no free slots. Take last+1 slot and expand
380: * the array.
381: */
382: found = sc->channels_alloc;
383: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
1.403 djm 384: fatal_f("internal error: channels_alloc %d too big",
385: sc->channels_alloc);
1.367 djm 386: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
387: sc->channels_alloc + 10, sizeof(*sc->channels));
388: sc->channels_alloc += 10;
389: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 390: }
1.113 markus 391: /* Initialize and return new channel. */
1.367 djm 392: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
393: if ((c->input = sshbuf_new()) == NULL ||
394: (c->output = sshbuf_new()) == NULL ||
395: (c->extended = sshbuf_new()) == NULL)
1.403 djm 396: fatal_f("sshbuf_new failed");
1.402 djm 397: if ((r = sshbuf_set_max_size(c->input, CHAN_INPUT_MAX)) != 0)
1.403 djm 398: fatal_fr(r, "sshbuf_set_max_size");
1.159 markus 399: c->ostate = CHAN_OUTPUT_OPEN;
400: c->istate = CHAN_INPUT_OPEN;
1.367 djm 401: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 402: c->self = found;
403: c->type = type;
1.41 markus 404: c->ctype = ctype;
1.51 markus 405: c->local_window = window;
406: c->local_window_max = window;
407: c->local_maxpacket = maxpack;
1.190 markus 408: c->remote_name = xstrdup(remote_name);
1.302 djm 409: c->ctl_chan = -1;
1.299 markus 410: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 411: TAILQ_INIT(&c->status_confirms);
1.25 markus 412: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 413: return c;
1.1 deraadt 414: }
1.52 markus 415:
1.367 djm 416: static void
417: channel_find_maxfd(struct ssh_channels *sc)
1.132 markus 418: {
1.209 avsm 419: u_int i;
420: int max = 0;
1.132 markus 421: Channel *c;
422:
1.367 djm 423: for (i = 0; i < sc->channels_alloc; i++) {
424: c = sc->channels[i];
1.132 markus 425: if (c != NULL) {
1.352 deraadt 426: max = MAXIMUM(max, c->rfd);
427: max = MAXIMUM(max, c->wfd);
428: max = MAXIMUM(max, c->efd);
1.132 markus 429: }
430: }
1.367 djm 431: sc->channel_max_fd = max;
1.132 markus 432: }
433:
434: int
1.407 ! djm 435: channel_close_fd(struct ssh *ssh, Channel *c, int *fdp)
1.132 markus 436: {
1.367 djm 437: struct ssh_channels *sc = ssh->chanctxt;
1.407 ! djm 438: int ret, fd = *fdp;
1.132 markus 439:
1.407 ! djm 440: if (fd == -1)
! 441: return 0;
! 442:
! 443: if ((*fdp == c->rfd && (c->restore_block & CHANNEL_RESTORE_RFD) != 0) ||
! 444: (*fdp == c->wfd && (c->restore_block & CHANNEL_RESTORE_WFD) != 0) ||
! 445: (*fdp == c->efd && (c->restore_block & CHANNEL_RESTORE_EFD) != 0))
! 446: (void)fcntl(*fdp, F_SETFL, 0); /* restore blocking */
! 447:
! 448: ret = close(fd);
! 449: *fdp = -1;
! 450: if (fd == sc->channel_max_fd)
! 451: channel_find_maxfd(sc);
1.132 markus 452: return ret;
453: }
454:
1.52 markus 455: /* Close all channel fd/socket. */
1.127 itojun 456: static void
1.367 djm 457: channel_close_fds(struct ssh *ssh, Channel *c)
458: {
1.379 tb 459: int sock = c->sock, rfd = c->rfd, wfd = c->wfd, efd = c->efd;
460:
1.407 ! djm 461: channel_close_fd(ssh, c, &c->sock);
1.379 tb 462: if (rfd != sock)
1.407 ! djm 463: channel_close_fd(ssh, c, &c->rfd);
1.379 tb 464: if (wfd != sock && wfd != rfd)
1.407 ! djm 465: channel_close_fd(ssh, c, &c->wfd);
1.379 tb 466: if (efd != sock && efd != rfd && efd != wfd)
1.407 ! djm 467: channel_close_fd(ssh, c, &c->efd);
1.367 djm 468: }
469:
470: static void
1.381 djm 471: fwd_perm_clear(struct permission *perm)
1.52 markus 472: {
1.381 djm 473: free(perm->host_to_connect);
474: free(perm->listen_host);
475: free(perm->listen_path);
1.398 dtucker 476: memset(perm, 0, sizeof(*perm));
1.367 djm 477: }
478:
1.381 djm 479: /* Returns an printable name for the specified forwarding permission list */
480: static const char *
481: fwd_ident(int who, int where)
482: {
483: if (who == FORWARD_ADM) {
484: if (where == FORWARD_LOCAL)
485: return "admin local";
486: else if (where == FORWARD_REMOTE)
487: return "admin remote";
488: } else if (who == FORWARD_USER) {
489: if (where == FORWARD_LOCAL)
490: return "user local";
491: else if (where == FORWARD_REMOTE)
492: return "user remote";
493: }
494: fatal("Unknown forward permission list %d/%d", who, where);
495: }
496:
497: /* Returns the forwarding permission list for the specified direction */
498: static struct permission_set *
499: permission_set_get(struct ssh *ssh, int where)
500: {
501: struct ssh_channels *sc = ssh->chanctxt;
1.367 djm 502:
1.381 djm 503: switch (where) {
504: case FORWARD_LOCAL:
505: return &sc->local_perms;
506: break;
507: case FORWARD_REMOTE:
508: return &sc->remote_perms;
509: break;
510: default:
1.403 djm 511: fatal_f("invalid forwarding direction %d", where);
1.381 djm 512: }
513: }
514:
1.392 dtucker 515: /* Returns pointers to the specified forwarding list and its element count */
1.381 djm 516: static void
517: permission_set_get_array(struct ssh *ssh, int who, int where,
518: struct permission ***permpp, u_int **npermpp)
519: {
520: struct permission_set *pset = permission_set_get(ssh, where);
521:
522: switch (who) {
523: case FORWARD_USER:
524: *permpp = &pset->permitted_user;
525: *npermpp = &pset->num_permitted_user;
526: break;
527: case FORWARD_ADM:
528: *permpp = &pset->permitted_admin;
529: *npermpp = &pset->num_permitted_admin;
530: break;
531: default:
1.403 djm 532: fatal_f("invalid forwarding client %d", who);
1.381 djm 533: }
534: }
535:
536: /* Adds an entry to the spcified forwarding list */
1.367 djm 537: static int
1.381 djm 538: permission_set_add(struct ssh *ssh, int who, int where,
1.367 djm 539: const char *host_to_connect, int port_to_connect,
540: const char *listen_host, const char *listen_path, int listen_port,
541: Channel *downstream)
542: {
1.381 djm 543: struct permission **permp;
544: u_int n, *npermp;
1.367 djm 545:
1.381 djm 546: permission_set_get_array(ssh, who, where, &permp, &npermp);
1.367 djm 547:
1.381 djm 548: if (*npermp >= INT_MAX)
1.403 djm 549: fatal_f("%s overflow", fwd_ident(who, where));
1.367 djm 550:
1.381 djm 551: *permp = xrecallocarray(*permp, *npermp, *npermp + 1, sizeof(**permp));
552: n = (*npermp)++;
1.367 djm 553: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
1.381 djm 554: (*permp)[n].host_to_connect = MAYBE_DUP(host_to_connect);
555: (*permp)[n].port_to_connect = port_to_connect;
556: (*permp)[n].listen_host = MAYBE_DUP(listen_host);
557: (*permp)[n].listen_path = MAYBE_DUP(listen_path);
558: (*permp)[n].listen_port = listen_port;
559: (*permp)[n].downstream = downstream;
1.367 djm 560: #undef MAYBE_DUP
561: return (int)n;
562: }
563:
564: static void
565: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
566: {
567: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 568: struct permission_set *pset = &sc->local_perms;
569: struct permission *perm;
1.367 djm 570: int r;
571: u_int i;
572:
1.381 djm 573: for (i = 0; i < pset->num_permitted_user; i++) {
574: perm = &pset->permitted_user[i];
575: if (perm->downstream != c)
1.367 djm 576: continue;
577:
578: /* cancel on the server, since mux client is gone */
579: debug("channel %d: cleanup remote forward for %s:%u",
1.381 djm 580: c->self, perm->listen_host, perm->listen_port);
1.367 djm 581: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
582: (r = sshpkt_put_cstring(ssh,
583: "cancel-tcpip-forward")) != 0 ||
584: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
585: (r = sshpkt_put_cstring(ssh,
1.381 djm 586: channel_rfwd_bind_host(perm->listen_host))) != 0 ||
587: (r = sshpkt_put_u32(ssh, perm->listen_port)) != 0 ||
1.367 djm 588: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 589: fatal_fr(r, "channel %i", c->self);
1.367 djm 590: }
1.381 djm 591: fwd_perm_clear(perm); /* unregister */
1.367 djm 592: }
1.121 markus 593: }
594:
595: /* Free the channel and close its fd/socket. */
596: void
1.367 djm 597: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 598: {
1.367 djm 599: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 600: char *s;
1.209 avsm 601: u_int i, n;
1.354 markus 602: Channel *other;
1.275 djm 603: struct channel_confirm *cc;
1.121 markus 604:
1.367 djm 605: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
606: if ((other = sc->channels[i]) == NULL)
607: continue;
608: n++;
609: /* detach from mux client and prepare for closing */
610: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
611: other->type == SSH_CHANNEL_MUX_PROXY &&
612: other->mux_ctx == c) {
613: other->mux_ctx = NULL;
614: other->type = SSH_CHANNEL_OPEN;
615: other->istate = CHAN_INPUT_CLOSED;
616: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 617: }
618: }
1.209 avsm 619: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 620: c->remote_name ? c->remote_name : "???", n);
621:
1.367 djm 622: if (c->type == SSH_CHANNEL_MUX_CLIENT)
623: mux_remove_remote_forwardings(ssh, c);
1.401 djm 624: else if (c->type == SSH_CHANNEL_MUX_LISTENER) {
625: free(c->mux_ctx);
626: c->mux_ctx = NULL;
627: }
1.354 markus 628:
1.384 markus 629: if (log_level_get() >= SYSLOG_LEVEL_DEBUG3) {
630: s = channel_open_message(ssh);
631: debug3("channel %d: status: %s", c->self, s);
632: free(s);
633: }
1.121 markus 634:
1.367 djm 635: channel_close_fds(ssh, c);
636: sshbuf_free(c->input);
637: sshbuf_free(c->output);
638: sshbuf_free(c->extended);
639: c->input = c->output = c->extended = NULL;
1.321 djm 640: free(c->remote_name);
641: c->remote_name = NULL;
642: free(c->path);
643: c->path = NULL;
644: free(c->listening_addr);
645: c->listening_addr = NULL;
1.275 djm 646: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
647: if (cc->abandon_cb != NULL)
1.367 djm 648: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 649: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 650: freezero(cc, sizeof(*cc));
1.275 djm 651: }
1.280 djm 652: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 653: c->filter_cleanup(ssh, c->self, c->filter_ctx);
654: sc->channels[c->self] = NULL;
1.396 jsg 655: freezero(c, sizeof(*c));
1.121 markus 656: }
657:
658: void
1.367 djm 659: channel_free_all(struct ssh *ssh)
1.121 markus 660: {
1.209 avsm 661: u_int i;
1.390 dtucker 662: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 663:
1.390 dtucker 664: for (i = 0; i < sc->channels_alloc; i++)
665: if (sc->channels[i] != NULL)
666: channel_free(ssh, sc->channels[i]);
667:
668: free(sc->channels);
669: sc->channels = NULL;
670: sc->channels_alloc = 0;
671: sc->channel_max_fd = 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 "
863: "fd %d/%d/%d sock %d cc %d",
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),
869: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan);
870: return ret;
871: }
872:
1.121 markus 873: /*
874: * Returns a message describing the currently open forwarded connections,
875: * suitable for sending to the client. The message contains crlf pairs for
876: * newlines.
877: */
878: char *
1.367 djm 879: channel_open_message(struct ssh *ssh)
1.121 markus 880: {
1.367 djm 881: struct sshbuf *buf;
1.121 markus 882: Channel *c;
1.209 avsm 883: u_int i;
1.367 djm 884: int r;
1.386 djm 885: char *cp, *ret;
1.121 markus 886:
1.367 djm 887: if ((buf = sshbuf_new()) == NULL)
1.403 djm 888: fatal_f("sshbuf_new");
1.367 djm 889: if ((r = sshbuf_putf(buf,
890: "The following connections are open:\r\n")) != 0)
1.403 djm 891: fatal_fr(r, "sshbuf_putf");
1.367 djm 892: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
893: c = ssh->chanctxt->channels[i];
1.121 markus 894: if (c == NULL)
895: continue;
896: switch (c->type) {
897: case SSH_CHANNEL_X11_LISTENER:
898: case SSH_CHANNEL_PORT_LISTENER:
899: case SSH_CHANNEL_RPORT_LISTENER:
900: case SSH_CHANNEL_CLOSED:
901: case SSH_CHANNEL_AUTH_SOCKET:
902: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 903: case SSH_CHANNEL_ABANDONED:
1.302 djm 904: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 905: case SSH_CHANNEL_UNIX_LISTENER:
906: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 907: continue;
908: case SSH_CHANNEL_LARVAL:
909: case SSH_CHANNEL_OPENING:
910: case SSH_CHANNEL_CONNECTING:
911: case SSH_CHANNEL_DYNAMIC:
1.372 markus 912: case SSH_CHANNEL_RDYNAMIC_OPEN:
913: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 914: case SSH_CHANNEL_OPEN:
915: case SSH_CHANNEL_X11_OPEN:
1.354 markus 916: case SSH_CHANNEL_MUX_PROXY:
917: case SSH_CHANNEL_MUX_CLIENT:
1.386 djm 918: cp = channel_format_status(c);
919: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
920: c->self, c->remote_name, cp)) != 0) {
921: free(cp);
1.403 djm 922: fatal_fr(r, "sshbuf_putf");
1.386 djm 923: }
924: free(cp);
1.121 markus 925: continue;
926: default:
1.403 djm 927: fatal_f("bad channel type %d", c->type);
1.121 markus 928: /* NOTREACHED */
929: }
930: }
1.367 djm 931: if ((ret = sshbuf_dup_string(buf)) == NULL)
1.403 djm 932: fatal_f("sshbuf_dup_string");
1.367 djm 933: sshbuf_free(buf);
934: return ret;
935: }
936:
937: static void
938: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
939: {
940: int r;
941:
942: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
943: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
944: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
945: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
946: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
1.403 djm 947: fatal_r(r, "%s: channel %i: open", where, c->self);
1.367 djm 948: }
1.121 markus 949: }
950:
951: void
1.367 djm 952: channel_send_open(struct ssh *ssh, int id)
1.121 markus 953: {
1.367 djm 954: Channel *c = channel_lookup(ssh, id);
955: int r;
1.180 deraadt 956:
1.121 markus 957: if (c == NULL) {
1.188 itojun 958: logit("channel_send_open: %d: bad id", id);
1.121 markus 959: return;
960: }
1.184 markus 961: debug2("channel %d: send open", id);
1.367 djm 962: open_preamble(ssh, __func__, c, c->ctype);
963: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 964: fatal_fr(r, "channel %i", c->self);
1.121 markus 965: }
966:
967: void
1.367 djm 968: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 969: {
1.367 djm 970: Channel *c = channel_lookup(ssh, id);
971: int r;
1.180 deraadt 972:
1.121 markus 973: if (c == NULL) {
1.403 djm 974: logit_f("%d: unknown channel id", id);
1.121 markus 975: return;
976: }
1.368 djm 977: if (!c->have_remote_id)
1.403 djm 978: fatal_f("channel %d: no remote id", c->self);
1.368 djm 979:
1.204 djm 980: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 981: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
982: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
983: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
984: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
1.403 djm 985: fatal_fr(r, "channel %i", c->self);
1.367 djm 986: }
1.121 markus 987: }
1.241 deraadt 988:
1.121 markus 989: void
1.367 djm 990: channel_register_status_confirm(struct ssh *ssh, int id,
991: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 992: {
993: struct channel_confirm *cc;
994: Channel *c;
995:
1.367 djm 996: if ((c = channel_lookup(ssh, id)) == NULL)
1.403 djm 997: fatal_f("%d: bad id", id);
1.275 djm 998:
1.327 djm 999: cc = xcalloc(1, sizeof(*cc));
1.275 djm 1000: cc->cb = cb;
1001: cc->abandon_cb = abandon_cb;
1002: cc->ctx = ctx;
1003: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
1004: }
1005:
1006: void
1.367 djm 1007: channel_register_open_confirm(struct ssh *ssh, int id,
1008: channel_open_fn *fn, void *ctx)
1.121 markus 1009: {
1.367 djm 1010: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1011:
1.121 markus 1012: if (c == NULL) {
1.403 djm 1013: logit_f("%d: bad id", id);
1.121 markus 1014: return;
1015: }
1.275 djm 1016: c->open_confirm = fn;
1017: c->open_confirm_ctx = ctx;
1.121 markus 1018: }
1.241 deraadt 1019:
1.121 markus 1020: void
1.367 djm 1021: channel_register_cleanup(struct ssh *ssh, int id,
1022: channel_callback_fn *fn, int do_close)
1.121 markus 1023: {
1.367 djm 1024: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1025:
1.121 markus 1026: if (c == NULL) {
1.403 djm 1027: logit_f("%d: bad id", id);
1.121 markus 1028: return;
1029: }
1.131 markus 1030: c->detach_user = fn;
1.225 djm 1031: c->detach_close = do_close;
1.121 markus 1032: }
1.241 deraadt 1033:
1.121 markus 1034: void
1.367 djm 1035: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 1036: {
1.367 djm 1037: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1038:
1.121 markus 1039: if (c == NULL) {
1.403 djm 1040: logit_f("%d: bad id", id);
1.121 markus 1041: return;
1.52 markus 1042: }
1.131 markus 1043: c->detach_user = NULL;
1.225 djm 1044: c->detach_close = 0;
1.121 markus 1045: }
1.241 deraadt 1046:
1.121 markus 1047: void
1.367 djm 1048: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1049: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1050: {
1.367 djm 1051: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1052:
1.121 markus 1053: if (c == NULL) {
1.403 djm 1054: logit_f("%d: bad id", id);
1.121 markus 1055: return;
1.52 markus 1056: }
1.231 reyk 1057: c->input_filter = ifn;
1058: c->output_filter = ofn;
1.279 djm 1059: c->filter_ctx = ctx;
1.280 djm 1060: c->filter_cleanup = cfn;
1.52 markus 1061: }
1062:
1.49 markus 1063: void
1.367 djm 1064: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1065: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1066: {
1.367 djm 1067: Channel *c = channel_lookup(ssh, id);
1068: int r;
1.180 deraadt 1069:
1.121 markus 1070: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1071: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1072: if (!c->have_remote_id)
1.403 djm 1073: fatal_f("channel %d: no remote id", c->self);
1.368 djm 1074:
1.367 djm 1075: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1076: c->type = SSH_CHANNEL_OPEN;
1.168 markus 1077: c->local_window = c->local_window_max = window_max;
1.367 djm 1078:
1079: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1080: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1081: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1082: (r = sshpkt_send(ssh)) != 0)
1.403 djm 1083: fatal_fr(r, "channel %i", c->self);
1.1 deraadt 1084: }
1085:
1.127 itojun 1086: static void
1.367 djm 1087: channel_pre_listener(struct ssh *ssh, Channel *c,
1088: fd_set *readset, fd_set *writeset)
1.41 markus 1089: {
1090: FD_SET(c->sock, readset);
1091: }
1092:
1.127 itojun 1093: static void
1.367 djm 1094: channel_pre_connecting(struct ssh *ssh, Channel *c,
1095: fd_set *readset, fd_set *writeset)
1.75 markus 1096: {
1097: debug3("channel %d: waiting for connection", c->self);
1098: FD_SET(c->sock, writeset);
1099: }
1100:
1.127 itojun 1101: static void
1.367 djm 1102: channel_pre_open(struct ssh *ssh, Channel *c,
1103: fd_set *readset, fd_set *writeset)
1.41 markus 1104: {
1.44 markus 1105: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1106: c->remote_window > 0 &&
1.367 djm 1107: sshbuf_len(c->input) < c->remote_window &&
1108: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.44 markus 1109: FD_SET(c->rfd, readset);
1110: if (c->ostate == CHAN_OUTPUT_OPEN ||
1111: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1112: if (sshbuf_len(c->output) > 0) {
1.44 markus 1113: FD_SET(c->wfd, writeset);
1114: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1115: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1116: debug2("channel %d: "
1117: "obuf_empty delayed efd %d/(%zu)", c->self,
1118: c->efd, sshbuf_len(c->extended));
1.172 markus 1119: else
1.367 djm 1120: chan_obuf_empty(ssh, c);
1.44 markus 1121: }
1122: }
1123: /** XXX check close conditions, too */
1.358 djm 1124: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1125: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1126: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1127: sshbuf_len(c->extended) > 0)
1.44 markus 1128: FD_SET(c->efd, writeset);
1.306 djm 1129: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1130: (c->extended_usage == CHAN_EXTENDED_READ ||
1131: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1132: sshbuf_len(c->extended) < c->remote_window)
1.44 markus 1133: FD_SET(c->efd, readset);
1134: }
1.204 djm 1135: /* XXX: What about efd? races? */
1.44 markus 1136: }
1137:
1.41 markus 1138: /*
1139: * This is a special state for X11 authentication spoofing. An opened X11
1140: * connection (when authentication spoofing is being done) remains in this
1141: * state until the first packet has been completely read. The authentication
1142: * data in that packet is then substituted by the real data if it matches the
1143: * fake data, and the channel is put into normal mode.
1.51 markus 1144: * XXX All this happens at the client side.
1.121 markus 1145: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1146: */
1.127 itojun 1147: static int
1.367 djm 1148: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1149: {
1.367 djm 1150: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1151: u_char *ucp;
1152: u_int proto_len, data_len;
1.25 markus 1153:
1.347 djm 1154: /* Is this being called after the refusal deadline? */
1.367 djm 1155: if (sc->x11_refuse_time != 0 &&
1156: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1157: verbose("Rejected X11 connection after ForwardX11Timeout "
1158: "expired");
1159: return -1;
1160: }
1161:
1.41 markus 1162: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1163: if (sshbuf_len(b) < 12)
1.41 markus 1164: return 0;
1165:
1166: /* Parse the lengths of variable-length fields. */
1.367 djm 1167: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1168: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1169: proto_len = 256 * ucp[6] + ucp[7];
1170: data_len = 256 * ucp[8] + ucp[9];
1171: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1172: proto_len = ucp[6] + 256 * ucp[7];
1173: data_len = ucp[8] + 256 * ucp[9];
1174: } else {
1.194 markus 1175: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1176: ucp[0]);
1.41 markus 1177: return -1;
1178: }
1179:
1180: /* Check if the whole packet is in buffer. */
1.367 djm 1181: if (sshbuf_len(b) <
1.41 markus 1182: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1183: return 0;
1184:
1185: /* Check if authentication protocol matches. */
1.367 djm 1186: if (proto_len != strlen(sc->x11_saved_proto) ||
1187: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1188: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1189: return -1;
1190: }
1191: /* Check if authentication data matches our fake data. */
1.367 djm 1192: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1193: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1194: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1195: debug2("X11 auth data does not match fake data.");
1.41 markus 1196: return -1;
1197: }
1198: /* Check fake data length */
1.367 djm 1199: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1200: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1201: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1202: return -1;
1203: }
1204: /*
1205: * Received authentication protocol and data match
1206: * our fake data. Substitute the fake data with real
1207: * data.
1208: */
1209: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1210: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1211: return 1;
1212: }
1213:
1.127 itojun 1214: static void
1.367 djm 1215: channel_pre_x11_open(struct ssh *ssh, Channel *c,
1216: fd_set *readset, fd_set *writeset)
1.41 markus 1217: {
1.367 djm 1218: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1219:
1220: /* c->force_drain = 1; */
1221:
1.41 markus 1222: if (ret == 1) {
1223: c->type = SSH_CHANNEL_OPEN;
1.367 djm 1224: channel_pre_open(ssh, c, readset, writeset);
1.41 markus 1225: } else if (ret == -1) {
1.188 itojun 1226: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1227: debug2("X11 rejected %d i%d/o%d",
1228: c->self, c->istate, c->ostate);
1229: chan_read_failed(ssh, c);
1230: sshbuf_reset(c->input);
1231: chan_ibuf_empty(ssh, c);
1232: sshbuf_reset(c->output);
1233: chan_write_failed(ssh, c);
1.194 markus 1234: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1235: }
1236: }
1.25 markus 1237:
1.302 djm 1238: static void
1.367 djm 1239: channel_pre_mux_client(struct ssh *ssh,
1240: Channel *c, fd_set *readset, fd_set *writeset)
1.302 djm 1241: {
1.304 djm 1242: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1243: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.302 djm 1244: FD_SET(c->rfd, readset);
1245: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1246: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1247: sshbuf_reset(c->input);
1248: chan_ibuf_empty(ssh, c);
1.302 djm 1249: /* Start output drain. XXX just kill chan? */
1.367 djm 1250: chan_rcvd_oclose(ssh, c);
1.302 djm 1251: }
1252: if (c->ostate == CHAN_OUTPUT_OPEN ||
1253: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1254: if (sshbuf_len(c->output) > 0)
1.302 djm 1255: FD_SET(c->wfd, writeset);
1256: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1257: chan_obuf_empty(ssh, c);
1.302 djm 1258: }
1259: }
1260:
1.104 markus 1261: /* try to decode a socks4 header */
1.127 itojun 1262: static int
1.372 markus 1263: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1264: {
1.367 djm 1265: const u_char *p;
1266: char *host;
1.292 djm 1267: u_int len, have, i, found, need;
1.148 deraadt 1268: char username[256];
1.103 markus 1269: struct {
1270: u_int8_t version;
1271: u_int8_t command;
1272: u_int16_t dest_port;
1.104 markus 1273: struct in_addr dest_addr;
1.103 markus 1274: } s4_req, s4_rsp;
1.367 djm 1275: int r;
1.103 markus 1276:
1.104 markus 1277: debug2("channel %d: decode socks4", c->self);
1.109 markus 1278:
1.372 markus 1279: have = sshbuf_len(input);
1.109 markus 1280: len = sizeof(s4_req);
1281: if (have < len)
1282: return 0;
1.372 markus 1283: p = sshbuf_ptr(input);
1.292 djm 1284:
1285: need = 1;
1286: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1287: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1288: debug2("channel %d: socks4a request", c->self);
1289: /* ... and needs an extra string (the hostname) */
1290: need = 2;
1291: }
1292: /* Check for terminating NUL on the string(s) */
1.109 markus 1293: for (found = 0, i = len; i < have; i++) {
1294: if (p[i] == '\0') {
1.292 djm 1295: found++;
1296: if (found == need)
1297: break;
1.109 markus 1298: }
1299: if (i > 1024) {
1300: /* the peer is probably sending garbage */
1301: debug("channel %d: decode socks4: too long",
1302: c->self);
1303: return -1;
1304: }
1305: }
1.292 djm 1306: if (found < need)
1.109 markus 1307: return 0;
1.372 markus 1308: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1309: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1310: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1311: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.403 djm 1312: debug_r(r, "channels %d: decode socks4", c->self);
1.367 djm 1313: return -1;
1314: }
1.372 markus 1315: have = sshbuf_len(input);
1316: p = sshbuf_ptr(input);
1.364 djm 1317: if (memchr(p, '\0', have) == NULL) {
1.403 djm 1318: error("channel %d: decode socks4: unterminated user", c->self);
1.364 djm 1319: return -1;
1320: }
1.103 markus 1321: len = strlen(p);
1.106 markus 1322: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1323: len++; /* trailing '\0' */
1.103 markus 1324: strlcpy(username, p, sizeof(username));
1.403 djm 1325: if ((r = sshbuf_consume(input, len)) != 0)
1326: fatal_fr(r, "channel %d: consume", c->self);
1.321 djm 1327: free(c->path);
1328: c->path = NULL;
1.292 djm 1329: if (need == 1) { /* SOCKS4: one string */
1330: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1331: c->path = xstrdup(host);
1.292 djm 1332: } else { /* SOCKS4A: two strings */
1.372 markus 1333: have = sshbuf_len(input);
1334: p = sshbuf_ptr(input);
1.364 djm 1335: if (memchr(p, '\0', have) == NULL) {
1336: error("channel %d: decode socks4a: host not nul "
1337: "terminated", c->self);
1338: return -1;
1339: }
1.292 djm 1340: len = strlen(p);
1341: debug2("channel %d: decode socks4a: host %s/%d",
1342: c->self, p, len);
1343: len++; /* trailing '\0' */
1.293 djm 1344: if (len > NI_MAXHOST) {
1.292 djm 1345: error("channel %d: hostname \"%.100s\" too long",
1346: c->self, p);
1347: return -1;
1348: }
1.293 djm 1349: c->path = xstrdup(p);
1.403 djm 1350: if ((r = sshbuf_consume(input, len)) != 0)
1351: fatal_fr(r, "channel %d: consume", c->self);
1.292 djm 1352: }
1.103 markus 1353: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1354:
1.194 markus 1355: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1356: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1357:
1.104 markus 1358: if (s4_req.command != 1) {
1.292 djm 1359: debug("channel %d: cannot handle: %s cn %d",
1360: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1361: return -1;
1.103 markus 1362: }
1.104 markus 1363: s4_rsp.version = 0; /* vn: 0 for reply */
1364: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1365: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1366: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.403 djm 1367: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0)
1368: fatal_fr(r, "channel %d: append reply", c->self);
1.104 markus 1369: return 1;
1370: }
1371:
1.193 markus 1372: /* try to decode a socks5 header */
1373: #define SSH_SOCKS5_AUTHDONE 0x1000
1374: #define SSH_SOCKS5_NOAUTH 0x00
1375: #define SSH_SOCKS5_IPV4 0x01
1376: #define SSH_SOCKS5_DOMAIN 0x03
1377: #define SSH_SOCKS5_IPV6 0x04
1378: #define SSH_SOCKS5_CONNECT 0x01
1379: #define SSH_SOCKS5_SUCCESS 0x00
1380:
1381: static int
1.372 markus 1382: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1383: {
1.367 djm 1384: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1385: struct {
1386: u_int8_t version;
1387: u_int8_t command;
1388: u_int8_t reserved;
1389: u_int8_t atyp;
1390: } s5_req, s5_rsp;
1391: u_int16_t dest_port;
1.324 djm 1392: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1393: const u_char *p;
1.252 djm 1394: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1395: int r;
1.193 markus 1396:
1397: debug2("channel %d: decode socks5", c->self);
1.372 markus 1398: p = sshbuf_ptr(input);
1.193 markus 1399: if (p[0] != 0x05)
1400: return -1;
1.372 markus 1401: have = sshbuf_len(input);
1.193 markus 1402: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1403: /* format: ver | nmethods | methods */
1.198 djm 1404: if (have < 2)
1.193 markus 1405: return 0;
1406: nmethods = p[1];
1407: if (have < nmethods + 2)
1408: return 0;
1409: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1410: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1411: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1412: found = 1;
1413: break;
1414: }
1415: }
1416: if (!found) {
1417: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1418: c->self);
1419: return -1;
1420: }
1.403 djm 1421: if ((r = sshbuf_consume(input, nmethods + 2)) != 0)
1422: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1423: /* version, method */
1.372 markus 1424: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1.403 djm 1425: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0)
1426: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1427: c->flags |= SSH_SOCKS5_AUTHDONE;
1428: debug2("channel %d: socks5 auth done", c->self);
1429: return 0; /* need more */
1430: }
1431: debug2("channel %d: socks5 post auth", c->self);
1432: if (have < sizeof(s5_req)+1)
1433: return 0; /* need more */
1.247 deraadt 1434: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1435: if (s5_req.version != 0x05 ||
1436: s5_req.command != SSH_SOCKS5_CONNECT ||
1437: s5_req.reserved != 0x00) {
1.194 markus 1438: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1439: return -1;
1440: }
1.213 deraadt 1441: switch (s5_req.atyp){
1.193 markus 1442: case SSH_SOCKS5_IPV4:
1443: addrlen = 4;
1444: af = AF_INET;
1445: break;
1446: case SSH_SOCKS5_DOMAIN:
1447: addrlen = p[sizeof(s5_req)];
1448: af = -1;
1449: break;
1450: case SSH_SOCKS5_IPV6:
1451: addrlen = 16;
1452: af = AF_INET6;
1453: break;
1454: default:
1.194 markus 1455: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1456: return -1;
1457: }
1.252 djm 1458: need = sizeof(s5_req) + addrlen + 2;
1459: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1460: need++;
1461: if (have < need)
1.193 markus 1462: return 0;
1.403 djm 1463: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0)
1464: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1465: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1466: /* host string length */
1.403 djm 1467: if ((r = sshbuf_consume(input, 1)) != 0)
1468: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1469: }
1.372 markus 1470: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1471: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.403 djm 1472: debug_r(r, "channel %d: parse addr/port", c->self);
1.367 djm 1473: return -1;
1474: }
1.193 markus 1475: dest_addr[addrlen] = '\0';
1.321 djm 1476: free(c->path);
1477: c->path = NULL;
1.293 djm 1478: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1479: if (addrlen >= NI_MAXHOST) {
1.293 djm 1480: error("channel %d: dynamic request: socks5 hostname "
1481: "\"%.100s\" too long", c->self, dest_addr);
1482: return -1;
1483: }
1484: c->path = xstrdup(dest_addr);
1485: } else {
1486: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1487: return -1;
1488: c->path = xstrdup(ntop);
1489: }
1.193 markus 1490: c->host_port = ntohs(dest_port);
1.198 djm 1491:
1.194 markus 1492: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1493: c->self, c->path, c->host_port, s5_req.command);
1494:
1495: s5_rsp.version = 0x05;
1496: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1497: s5_rsp.reserved = 0; /* ignored */
1498: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1499: dest_port = 0; /* ignored */
1500:
1.372 markus 1501: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1502: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1503: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.403 djm 1504: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1505: return 1;
1.301 dtucker 1506: }
1507:
1508: Channel *
1.367 djm 1509: channel_connect_stdio_fwd(struct ssh *ssh,
1.407 ! djm 1510: const char *host_to_connect, u_short port_to_connect,
! 1511: int in, int out, int nonblock)
1.301 dtucker 1512: {
1513: Channel *c;
1514:
1.403 djm 1515: debug_f("%s:%d", host_to_connect, port_to_connect);
1.301 dtucker 1516:
1.367 djm 1517: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1518: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.407 ! djm 1519: 0, "stdio-forward", nonblock);
1.301 dtucker 1520:
1521: c->path = xstrdup(host_to_connect);
1522: c->host_port = port_to_connect;
1523: c->listening_port = 0;
1524: c->force_drain = 1;
1525:
1.367 djm 1526: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1527: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1528:
1529: return c;
1.193 markus 1530: }
1531:
1.104 markus 1532: /* dynamic port forwarding */
1.127 itojun 1533: static void
1.367 djm 1534: channel_pre_dynamic(struct ssh *ssh, Channel *c,
1535: fd_set *readset, fd_set *writeset)
1.104 markus 1536: {
1.367 djm 1537: const u_char *p;
1.217 djm 1538: u_int have;
1539: int ret;
1.103 markus 1540:
1.367 djm 1541: have = sshbuf_len(c->input);
1.104 markus 1542: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1543: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1544: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1545: if (have < 3) {
1.104 markus 1546: /* need more */
1547: FD_SET(c->sock, readset);
1548: return;
1549: }
1550: /* try to guess the protocol */
1.367 djm 1551: p = sshbuf_ptr(c->input);
1552: /* XXX sshbuf_peek_u8? */
1.104 markus 1553: switch (p[0]) {
1554: case 0x04:
1.372 markus 1555: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1556: break;
1557: case 0x05:
1.372 markus 1558: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1559: break;
1560: default:
1561: ret = -1;
1562: break;
1563: }
1564: if (ret < 0) {
1.367 djm 1565: chan_mark_dead(ssh, c);
1.104 markus 1566: } else if (ret == 0) {
1567: debug2("channel %d: pre_dynamic: need more", c->self);
1568: /* need more */
1569: FD_SET(c->sock, readset);
1.372 markus 1570: if (sshbuf_len(c->output))
1571: FD_SET(c->sock, writeset);
1.104 markus 1572: } else {
1573: /* switch to the next state */
1574: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1575: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1576: }
1.103 markus 1577: }
1578:
1.372 markus 1579: /* simulate read-error */
1580: static void
1581: rdynamic_close(struct ssh *ssh, Channel *c)
1582: {
1583: c->type = SSH_CHANNEL_OPEN;
1584: chan_read_failed(ssh, c);
1585: sshbuf_reset(c->input);
1586: chan_ibuf_empty(ssh, c);
1587: sshbuf_reset(c->output);
1588: chan_write_failed(ssh, c);
1589: }
1590:
1591: /* reverse dynamic port forwarding */
1592: static void
1593: channel_before_prepare_select_rdynamic(struct ssh *ssh, Channel *c)
1594: {
1595: const u_char *p;
1596: u_int have, len;
1597: int r, ret;
1598:
1599: have = sshbuf_len(c->output);
1600: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1601: /* sshbuf_dump(c->output, stderr); */
1602: /* EOF received */
1603: if (c->flags & CHAN_EOF_RCVD) {
1.403 djm 1604: if ((r = sshbuf_consume(c->output, have)) != 0)
1605: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1606: rdynamic_close(ssh, c);
1607: return;
1608: }
1609: /* check if the fixed size part of the packet is in buffer. */
1610: if (have < 3)
1611: return;
1612: /* try to guess the protocol */
1613: p = sshbuf_ptr(c->output);
1614: switch (p[0]) {
1615: case 0x04:
1616: /* switch input/output for reverse forwarding */
1617: ret = channel_decode_socks4(c, c->output, c->input);
1618: break;
1619: case 0x05:
1620: ret = channel_decode_socks5(c, c->output, c->input);
1621: break;
1622: default:
1623: ret = -1;
1624: break;
1625: }
1626: if (ret < 0) {
1627: rdynamic_close(ssh, c);
1628: } else if (ret == 0) {
1629: debug2("channel %d: pre_rdynamic: need more", c->self);
1630: /* send socks request to peer */
1631: len = sshbuf_len(c->input);
1632: if (len > 0 && len < c->remote_window) {
1633: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1634: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1635: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1636: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 1637: fatal_fr(r, "channel %i: rdynamic", c->self);
1.372 markus 1638: }
1.403 djm 1639: if ((r = sshbuf_consume(c->input, len)) != 0)
1640: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1641: c->remote_window -= len;
1642: }
1643: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1644: /* the connect failed */
1645: rdynamic_close(ssh, c);
1646: }
1647: }
1648:
1.41 markus 1649: /* This is our fake X11 server socket. */
1.127 itojun 1650: static void
1.367 djm 1651: channel_post_x11_listener(struct ssh *ssh, Channel *c,
1652: fd_set *readset, fd_set *writeset)
1.41 markus 1653: {
1.113 markus 1654: Channel *nc;
1.285 djm 1655: struct sockaddr_storage addr;
1.367 djm 1656: int r, newsock, oerrno, remote_port;
1.41 markus 1657: socklen_t addrlen;
1.85 markus 1658: char buf[16384], *remote_ipaddr;
1.25 markus 1659:
1.367 djm 1660: if (!FD_ISSET(c->sock, readset))
1661: return;
1662:
1663: debug("X11 connection requested.");
1664: addrlen = sizeof(addr);
1665: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1666: if (c->single_connection) {
1667: oerrno = errno;
1668: debug2("single_connection: closing X11 listener.");
1.407 ! djm 1669: channel_close_fd(ssh, c, &c->sock);
1.367 djm 1670: chan_mark_dead(ssh, c);
1671: errno = oerrno;
1672: }
1.393 deraadt 1673: if (newsock == -1) {
1.367 djm 1674: if (errno != EINTR && errno != EWOULDBLOCK &&
1675: errno != ECONNABORTED)
1676: error("accept: %.100s", strerror(errno));
1677: if (errno == EMFILE || errno == ENFILE)
1678: c->notbefore = monotime() + 1;
1679: return;
1680: }
1681: set_nodelay(newsock);
1682: remote_ipaddr = get_peer_ipaddr(newsock);
1683: remote_port = get_peer_port(newsock);
1684: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1685: remote_ipaddr, remote_port);
1686:
1687: nc = channel_new(ssh, "accepted x11 socket",
1688: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1689: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1690: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1691: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1692: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.403 djm 1693: fatal_fr(r, "channel %i: reply", c->self);
1.41 markus 1694: }
1.367 djm 1695: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1696: fatal_fr(r, "channel %i: send", c->self);
1.367 djm 1697: free(remote_ipaddr);
1.41 markus 1698: }
1.25 markus 1699:
1.127 itojun 1700: static void
1.367 djm 1701: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1702: {
1.328 djm 1703: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1704: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1705: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1706: int remote_port = get_peer_port(c->sock);
1.367 djm 1707: int r;
1.303 djm 1708:
1709: if (remote_port == -1) {
1710: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1711: free(remote_ipaddr);
1.303 djm 1712: remote_ipaddr = xstrdup("127.0.0.1");
1713: remote_port = 65535;
1714: }
1.103 markus 1715:
1.367 djm 1716: free(c->remote_name);
1717: xasprintf(&c->remote_name,
1.103 markus 1718: "%s: listening port %d for %.100s port %d, "
1.328 djm 1719: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1720: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1721: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1722:
1.367 djm 1723: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1724: if (strcmp(rtype, "direct-tcpip") == 0) {
1725: /* target host, port */
1.367 djm 1726: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1727: (r = sshpkt_put_u32(ssh, c->host_port)) != 0)
1728: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1729: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1730: /* target path */
1.403 djm 1731: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1732: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1733: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1734: /* listen path */
1.403 djm 1735: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1736: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1737: } else {
1.358 djm 1738: /* listen address, port */
1.367 djm 1739: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1740: (r = sshpkt_put_u32(ssh, local_port)) != 0)
1741: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1742: }
1743: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1744: /* reserved for future owner/mode info */
1.403 djm 1745: if ((r = sshpkt_put_cstring(ssh, "")) != 0)
1746: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1747: } else {
1748: /* originator host and port */
1.367 djm 1749: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1.403 djm 1750: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0)
1751: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1752: }
1.367 djm 1753: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1754: fatal_fr(r, "channel %i: send", c->self);
1.321 djm 1755: free(remote_ipaddr);
1.328 djm 1756: free(local_ipaddr);
1.103 markus 1757: }
1758:
1.347 djm 1759: void
1.367 djm 1760: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1761: {
1.367 djm 1762: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1763: }
1764:
1.41 markus 1765: /*
1766: * This socket is listening for connections to a forwarded TCP/IP port.
1767: */
1.127 itojun 1768: static void
1.367 djm 1769: channel_post_port_listener(struct ssh *ssh, Channel *c,
1770: fd_set *readset, fd_set *writeset)
1.41 markus 1771: {
1.103 markus 1772: Channel *nc;
1.285 djm 1773: struct sockaddr_storage addr;
1.113 markus 1774: int newsock, nextstate;
1.41 markus 1775: socklen_t addrlen;
1.103 markus 1776: char *rtype;
1.73 markus 1777:
1.367 djm 1778: if (!FD_ISSET(c->sock, readset))
1779: return;
1780:
1781: debug("Connection to port %d forwarding to %.100s port %d requested.",
1782: c->listening_port, c->path, c->host_port);
1.103 markus 1783:
1.367 djm 1784: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1785: nextstate = SSH_CHANNEL_OPENING;
1786: rtype = "forwarded-tcpip";
1787: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1788: nextstate = SSH_CHANNEL_OPENING;
1789: rtype = "forwarded-streamlocal@openssh.com";
1790: } else if (c->host_port == PORT_STREAMLOCAL) {
1791: nextstate = SSH_CHANNEL_OPENING;
1792: rtype = "direct-streamlocal@openssh.com";
1793: } else if (c->host_port == 0) {
1794: nextstate = SSH_CHANNEL_DYNAMIC;
1795: rtype = "dynamic-tcpip";
1796: } else {
1797: nextstate = SSH_CHANNEL_OPENING;
1798: rtype = "direct-tcpip";
1799: }
1.103 markus 1800:
1.367 djm 1801: addrlen = sizeof(addr);
1802: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1803: if (newsock == -1) {
1.367 djm 1804: if (errno != EINTR && errno != EWOULDBLOCK &&
1805: errno != ECONNABORTED)
1806: error("accept: %.100s", strerror(errno));
1807: if (errno == EMFILE || errno == ENFILE)
1808: c->notbefore = monotime() + 1;
1809: return;
1.41 markus 1810: }
1.367 djm 1811: if (c->host_port != PORT_STREAMLOCAL)
1812: set_nodelay(newsock);
1813: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1814: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1815: nc->listening_port = c->listening_port;
1816: nc->host_port = c->host_port;
1817: if (c->path != NULL)
1818: nc->path = xstrdup(c->path);
1819:
1820: if (nextstate != SSH_CHANNEL_DYNAMIC)
1821: port_open_helper(ssh, nc, rtype);
1.41 markus 1822: }
1.25 markus 1823:
1.41 markus 1824: /*
1825: * This is the authentication agent socket listening for connections from
1826: * clients.
1827: */
1.127 itojun 1828: static void
1.367 djm 1829: channel_post_auth_listener(struct ssh *ssh, Channel *c,
1830: fd_set *readset, fd_set *writeset)
1.41 markus 1831: {
1.113 markus 1832: Channel *nc;
1.367 djm 1833: int r, newsock;
1.285 djm 1834: struct sockaddr_storage addr;
1.41 markus 1835: socklen_t addrlen;
1.25 markus 1836:
1.367 djm 1837: if (!FD_ISSET(c->sock, readset))
1838: return;
1839:
1840: addrlen = sizeof(addr);
1841: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1842: if (newsock == -1) {
1.367 djm 1843: error("accept from auth socket: %.100s", strerror(errno));
1844: if (errno == EMFILE || errno == ENFILE)
1845: c->notbefore = monotime() + 1;
1846: return;
1.41 markus 1847: }
1.367 djm 1848: nc = channel_new(ssh, "accepted auth socket",
1849: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1850: c->local_window_max, c->local_maxpacket,
1851: 0, "accepted auth socket", 1);
1852: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1853: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1854: fatal_fr(r, "channel %i", c->self);
1.41 markus 1855: }
1.25 markus 1856:
1.127 itojun 1857: static void
1.367 djm 1858: channel_post_connecting(struct ssh *ssh, Channel *c,
1859: fd_set *readset, fd_set *writeset)
1.75 markus 1860: {
1.372 markus 1861: int err = 0, sock, isopen, r;
1.129 stevesk 1862: socklen_t sz = sizeof(err);
1.114 markus 1863:
1.367 djm 1864: if (!FD_ISSET(c->sock, writeset))
1865: return;
1.368 djm 1866: if (!c->have_remote_id)
1.403 djm 1867: fatal_f("channel %d: no remote id", c->self);
1.372 markus 1868: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1869: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.393 deraadt 1870: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 1871: err = errno;
1872: error("getsockopt SO_ERROR failed");
1873: }
1874: if (err == 0) {
1875: debug("channel %d: connected to %s port %d",
1876: c->self, c->connect_ctx.host, c->connect_ctx.port);
1877: channel_connect_ctx_free(&c->connect_ctx);
1878: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1879: if (isopen) {
1880: /* no message necessary */
1881: } else {
1882: if ((r = sshpkt_start(ssh,
1883: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1884: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1885: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1886: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 1887: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0 ||
1888: (r = sshpkt_send(ssh)) != 0)
1889: fatal_fr(r, "channel %i open confirm", c->self);
1.367 djm 1890: }
1891: } else {
1892: debug("channel %d: connection failed: %s",
1893: c->self, strerror(err));
1894: /* Try next address, if any */
1895: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1896: close(c->sock);
1897: c->sock = c->rfd = c->wfd = sock;
1898: channel_find_maxfd(ssh->chanctxt);
1899: return;
1900: }
1901: /* Exhausted all addresses */
1902: error("connect_to %.100s port %d: failed.",
1903: c->connect_ctx.host, c->connect_ctx.port);
1904: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1905: if (isopen) {
1906: rdynamic_close(ssh, c);
1907: } else {
1908: if ((r = sshpkt_start(ssh,
1909: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1910: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 1911: (r = sshpkt_put_u32(ssh,
1912: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
1913: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1.403 djm 1914: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1915: (r = sshpkt_send(ssh)) != 0)
1916: fatal_fr(r, "channel %i: failure", c->self);
1.372 markus 1917: chan_mark_dead(ssh, c);
1.75 markus 1918: }
1919: }
1920: }
1921:
1.127 itojun 1922: static int
1.367 djm 1923: channel_handle_rfd(struct ssh *ssh, Channel *c,
1924: fd_set *readset, fd_set *writeset)
1.41 markus 1925: {
1.214 markus 1926: char buf[CHAN_RBUF];
1.367 djm 1927: ssize_t len;
1928: int r;
1.25 markus 1929:
1.367 djm 1930: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
1931: return 1;
1932:
1933: len = read(c->rfd, buf, sizeof(buf));
1.393 deraadt 1934: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 1935: return 1;
1936: if (len <= 0) {
1937: debug2("channel %d: read<=0 rfd %d len %zd",
1938: c->self, c->rfd, len);
1939: if (c->type != SSH_CHANNEL_OPEN) {
1940: debug2("channel %d: not open", c->self);
1941: chan_mark_dead(ssh, c);
1.41 markus 1942: return -1;
1.65 markus 1943: } else {
1.367 djm 1944: chan_read_failed(ssh, c);
1.65 markus 1945: }
1.367 djm 1946: return -1;
1947: }
1948: if (c->input_filter != NULL) {
1949: if (c->input_filter(ssh, c, buf, len) == -1) {
1950: debug2("channel %d: filter stops", c->self);
1951: chan_read_failed(ssh, c);
1952: }
1953: } else if (c->datagram) {
1954: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1.403 djm 1955: fatal_fr(r, "channel %i: put datagram", c->self);
1956: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
1957: fatal_fr(r, "channel %i: put data", c->self);
1.41 markus 1958: return 1;
1959: }
1.241 deraadt 1960:
1.127 itojun 1961: static int
1.367 djm 1962: channel_handle_wfd(struct ssh *ssh, Channel *c,
1963: fd_set *readset, fd_set *writeset)
1.41 markus 1964: {
1.95 markus 1965: struct termios tio;
1.367 djm 1966: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1967: size_t dlen, olen = 0;
1968: int r, len;
1969:
1970: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
1971: sshbuf_len(c->output) == 0)
1972: return 1;
1.25 markus 1973:
1.41 markus 1974: /* Send buffered output data to the socket. */
1.367 djm 1975: olen = sshbuf_len(c->output);
1976: if (c->output_filter != NULL) {
1977: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1978: debug2("channel %d: filter stops", c->self);
1979: if (c->type != SSH_CHANNEL_OPEN)
1980: chan_mark_dead(ssh, c);
1981: else
1982: chan_write_failed(ssh, c);
1983: return -1;
1.231 reyk 1984: }
1.367 djm 1985: } else if (c->datagram) {
1986: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1.403 djm 1987: fatal_fr(r, "channel %i: get datagram", c->self);
1.369 djm 1988: buf = data;
1.367 djm 1989: } else {
1990: buf = data = sshbuf_mutable_ptr(c->output);
1991: dlen = sshbuf_len(c->output);
1992: }
1.231 reyk 1993:
1.367 djm 1994: if (c->datagram) {
1995: /* ignore truncated writes, datagrams might get lost */
1.374 djm 1996: len = write(c->wfd, buf, dlen);
1.367 djm 1997: free(data);
1.393 deraadt 1998: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 1999: return 1;
1.367 djm 2000: if (len <= 0)
2001: goto write_fail;
2002: goto out;
2003: }
2004:
2005: len = write(c->wfd, buf, dlen);
1.393 deraadt 2006: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2007: return 1;
2008: if (len <= 0) {
2009: write_fail:
2010: if (c->type != SSH_CHANNEL_OPEN) {
2011: debug2("channel %d: not open", c->self);
2012: chan_mark_dead(ssh, c);
1.41 markus 2013: return -1;
1.367 djm 2014: } else {
2015: chan_write_failed(ssh, c);
1.91 markus 2016: }
1.367 djm 2017: return -1;
2018: }
2019: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2020: if (tcgetattr(c->wfd, &tio) == 0 &&
2021: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2022: /*
2023: * Simulate echo to reduce the impact of
2024: * traffic analysis. We need to match the
2025: * size of a SSH2_MSG_CHANNEL_DATA message
2026: * (4 byte channel id + buf)
2027: */
2028: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2029: (r = sshpkt_send(ssh)) != 0)
1.403 djm 2030: fatal_fr(r, "channel %i: ignore", c->self);
1.25 markus 2031: }
1.367 djm 2032: }
1.403 djm 2033: if ((r = sshbuf_consume(c->output, len)) != 0)
2034: fatal_fr(r, "channel %i: consume", c->self);
1.309 djm 2035: out:
1.367 djm 2036: c->local_consumed += olen - sshbuf_len(c->output);
2037:
2038: return 1;
2039: }
2040:
2041: static int
2042: channel_handle_efd_write(struct ssh *ssh, Channel *c,
2043: fd_set *readset, fd_set *writeset)
2044: {
2045: int r;
2046: ssize_t len;
2047:
2048: if (!FD_ISSET(c->efd, writeset) || sshbuf_len(c->extended) == 0)
2049: return 1;
2050:
2051: len = write(c->efd, sshbuf_ptr(c->extended),
2052: sshbuf_len(c->extended));
2053: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 deraadt 2054: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2055: return 1;
2056: if (len <= 0) {
2057: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1.407 ! djm 2058: channel_close_fd(ssh, c, &c->efd);
1.367 djm 2059: } else {
1.403 djm 2060: if ((r = sshbuf_consume(c->extended, len)) != 0)
2061: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2062: c->local_consumed += len;
2063: }
1.44 markus 2064: return 1;
2065: }
1.241 deraadt 2066:
1.127 itojun 2067: static int
1.367 djm 2068: channel_handle_efd_read(struct ssh *ssh, Channel *c,
2069: fd_set *readset, fd_set *writeset)
1.44 markus 2070: {
1.214 markus 2071: char buf[CHAN_RBUF];
1.367 djm 2072: int r;
2073: ssize_t len;
2074:
2075: if (!FD_ISSET(c->efd, readset))
2076: return 1;
1.44 markus 2077:
1.367 djm 2078: len = read(c->efd, buf, sizeof(buf));
2079: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 deraadt 2080: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2081: return 1;
2082: if (len <= 0) {
1.403 djm 2083: debug2("channel %d: closing read-efd %d", c->self, c->efd);
1.407 ! djm 2084: channel_close_fd(ssh, c, &c->efd);
1.403 djm 2085: } else if (c->extended_usage == CHAN_EXTENDED_IGNORE)
2086: debug3("channel %d: discard efd", c->self);
2087: else if ((r = sshbuf_put(c->extended, buf, len)) != 0)
2088: fatal_fr(r, "channel %i: append", c->self);
1.44 markus 2089: return 1;
2090: }
1.241 deraadt 2091:
1.127 itojun 2092: static int
1.367 djm 2093: channel_handle_efd(struct ssh *ssh, Channel *c,
2094: fd_set *readset, fd_set *writeset)
1.44 markus 2095: {
1.367 djm 2096: if (c->efd == -1)
2097: return 1;
2098:
2099: /** XXX handle drain efd, too */
2100:
2101: if (c->extended_usage == CHAN_EXTENDED_WRITE)
2102: return channel_handle_efd_write(ssh, c, readset, writeset);
2103: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2104: c->extended_usage == CHAN_EXTENDED_IGNORE)
2105: return channel_handle_efd_read(ssh, c, readset, writeset);
2106:
2107: return 1;
2108: }
2109:
2110: static int
2111: channel_check_window(struct ssh *ssh, Channel *c)
2112: {
2113: int r;
2114:
1.104 markus 2115: if (c->type == SSH_CHANNEL_OPEN &&
2116: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2117: ((c->local_window_max - c->local_window >
1.269 markus 2118: c->local_maxpacket*3) ||
2119: c->local_window < c->local_window_max/2) &&
1.44 markus 2120: c->local_consumed > 0) {
1.368 djm 2121: if (!c->have_remote_id)
1.403 djm 2122: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2123: if ((r = sshpkt_start(ssh,
2124: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2125: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2126: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2127: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2128: fatal_fr(r, "channel %i", c->self);
1.367 djm 2129: }
1.403 djm 2130: debug2("channel %d: window %d sent adjust %d", c->self,
2131: c->local_window, c->local_consumed);
1.44 markus 2132: c->local_window += c->local_consumed;
2133: c->local_consumed = 0;
1.1 deraadt 2134: }
1.41 markus 2135: return 1;
1.1 deraadt 2136: }
2137:
1.127 itojun 2138: static void
1.367 djm 2139: channel_post_open(struct ssh *ssh, Channel *c,
2140: fd_set *readset, fd_set *writeset)
1.41 markus 2141: {
1.367 djm 2142: channel_handle_rfd(ssh, c, readset, writeset);
2143: channel_handle_wfd(ssh, c, readset, writeset);
2144: channel_handle_efd(ssh, c, readset, writeset);
2145: channel_check_window(ssh, c);
1.44 markus 2146: }
2147:
1.302 djm 2148: static u_int
1.367 djm 2149: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2150: {
2151: char buf[CHAN_RBUF];
1.367 djm 2152: ssize_t len;
1.302 djm 2153: u_int rlen;
1.367 djm 2154: int r;
1.302 djm 2155:
1.367 djm 2156: if (sshbuf_len(c->input) < need) {
2157: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2158: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 deraadt 2159: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2160: return sshbuf_len(c->input);
1.302 djm 2161: if (len <= 0) {
1.367 djm 2162: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2163: c->self, c->rfd, len);
1.367 djm 2164: chan_read_failed(ssh, c);
1.349 naddy 2165: return 0;
1.403 djm 2166: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
2167: fatal_fr(r, "channel %i: append", c->self);
1.302 djm 2168: }
1.367 djm 2169: return sshbuf_len(c->input);
1.302 djm 2170: }
2171:
2172: static void
1.367 djm 2173: channel_post_mux_client_read(struct ssh *ssh, Channel *c,
2174: fd_set *readset, fd_set *writeset)
1.302 djm 2175: {
2176: u_int need;
2177:
1.367 djm 2178: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
2179: return;
2180: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2181: return;
2182: if (c->mux_pause)
2183: return;
2184:
2185: /*
2186: * Don't not read past the precise end of packets to
2187: * avoid disrupting fd passing.
2188: */
2189: if (read_mux(ssh, c, 4) < 4) /* read header */
2190: return;
2191: /* XXX sshbuf_peek_u32 */
2192: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2193: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2194: if (need > CHANNEL_MUX_MAX_PACKET) {
2195: debug2("channel %d: packet too big %u > %u",
2196: c->self, CHANNEL_MUX_MAX_PACKET, need);
2197: chan_rcvd_oclose(ssh, c);
2198: return;
2199: }
2200: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2201: return;
2202: if (c->mux_rcb(ssh, c) != 0) {
2203: debug("channel %d: mux_rcb failed", c->self);
2204: chan_mark_dead(ssh, c);
2205: return;
1.302 djm 2206: }
1.367 djm 2207: }
2208:
2209: static void
2210: channel_post_mux_client_write(struct ssh *ssh, Channel *c,
2211: fd_set *readset, fd_set *writeset)
2212: {
2213: ssize_t len;
2214: int r;
1.302 djm 2215:
1.367 djm 2216: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
2217: sshbuf_len(c->output) == 0)
2218: return;
2219:
2220: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 deraadt 2221: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2222: return;
2223: if (len <= 0) {
2224: chan_mark_dead(ssh, c);
2225: return;
1.302 djm 2226: }
1.367 djm 2227: if ((r = sshbuf_consume(c->output, len)) != 0)
1.403 djm 2228: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2229: }
2230:
2231: static void
2232: channel_post_mux_client(struct ssh *ssh, Channel *c,
2233: fd_set *readset, fd_set *writeset)
2234: {
2235: channel_post_mux_client_read(ssh, c, readset, writeset);
2236: channel_post_mux_client_write(ssh, c, readset, writeset);
1.302 djm 2237: }
2238:
2239: static void
1.367 djm 2240: channel_post_mux_listener(struct ssh *ssh, Channel *c,
2241: fd_set *readset, fd_set *writeset)
1.302 djm 2242: {
2243: Channel *nc;
2244: struct sockaddr_storage addr;
2245: socklen_t addrlen;
2246: int newsock;
2247: uid_t euid;
2248: gid_t egid;
2249:
2250: if (!FD_ISSET(c->sock, readset))
2251: return;
2252:
2253: debug("multiplexing control connection");
2254:
2255: /*
2256: * Accept connection on control socket
2257: */
2258: memset(&addr, 0, sizeof(addr));
2259: addrlen = sizeof(addr);
2260: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2261: &addrlen)) == -1) {
1.403 djm 2262: error_f("accept: %s", strerror(errno));
1.317 djm 2263: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2264: c->notbefore = monotime() + 1;
1.302 djm 2265: return;
2266: }
2267:
1.393 deraadt 2268: if (getpeereid(newsock, &euid, &egid) == -1) {
1.403 djm 2269: error_f("getpeereid failed: %s", strerror(errno));
1.302 djm 2270: close(newsock);
2271: return;
2272: }
2273: if ((euid != 0) && (getuid() != euid)) {
2274: error("multiplex uid mismatch: peer euid %u != uid %u",
2275: (u_int)euid, (u_int)getuid());
2276: close(newsock);
2277: return;
2278: }
1.367 djm 2279: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2280: newsock, newsock, -1, c->local_window_max,
2281: c->local_maxpacket, 0, "mux-control", 1);
2282: nc->mux_rcb = c->mux_rcb;
1.403 djm 2283: debug3_f("new mux channel %d fd %d", nc->self, nc->sock);
1.302 djm 2284: /* establish state */
1.367 djm 2285: nc->mux_rcb(ssh, nc);
1.302 djm 2286: /* mux state transitions must not elicit protocol messages */
2287: nc->flags |= CHAN_LOCAL;
2288: }
2289:
1.127 itojun 2290: static void
1.367 djm 2291: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2292: {
1.367 djm 2293: chan_fn **pre, **post;
2294:
2295: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
1.406 djm 2296: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
1.403 djm 2297: fatal_f("allocation failed");
1.367 djm 2298:
2299: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2300: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2301: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2302: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2303: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2304: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2305: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2306: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2307: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2308: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2309: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2310: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2311: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2312:
2313: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2314: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2315: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2316: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2317: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2318: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2319: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2320: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2321: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2322: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2323: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2324: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2325:
1.367 djm 2326: sc->channel_pre = pre;
2327: sc->channel_post = post;
1.44 markus 2328: }
2329:
1.140 markus 2330: /* gc dead channels */
2331: static void
1.367 djm 2332: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2333: {
2334: if (c == NULL)
2335: return;
2336: if (c->detach_user != NULL) {
1.367 djm 2337: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2338: return;
1.385 djm 2339:
1.194 markus 2340: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2341: c->detach_user(ssh, c->self, NULL);
1.140 markus 2342: /* if we still have a callback */
2343: if (c->detach_user != NULL)
2344: return;
1.194 markus 2345: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2346: }
1.367 djm 2347: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2348: return;
1.194 markus 2349: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2350: channel_free(ssh, c);
1.140 markus 2351: }
2352:
1.367 djm 2353: enum channel_table { CHAN_PRE, CHAN_POST };
2354:
1.127 itojun 2355: static void
1.367 djm 2356: channel_handler(struct ssh *ssh, int table,
1.366 djm 2357: fd_set *readset, fd_set *writeset, time_t *unpause_secs)
1.41 markus 2358: {
1.367 djm 2359: struct ssh_channels *sc = ssh->chanctxt;
2360: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2361: u_int i, oalloc;
1.41 markus 2362: Channel *c;
1.317 djm 2363: time_t now;
1.25 markus 2364:
1.322 dtucker 2365: now = monotime();
1.317 djm 2366: if (unpause_secs != NULL)
2367: *unpause_secs = 0;
1.367 djm 2368: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2369: c = sc->channels[i];
1.113 markus 2370: if (c == NULL)
1.41 markus 2371: continue;
1.299 markus 2372: if (c->delayed) {
1.367 djm 2373: if (table == CHAN_PRE)
1.299 markus 2374: c->delayed = 0;
2375: else
2376: continue;
2377: }
1.317 djm 2378: if (ftab[c->type] != NULL) {
2379: /*
2380: * Run handlers that are not paused.
2381: */
2382: if (c->notbefore <= now)
1.367 djm 2383: (*ftab[c->type])(ssh, c, readset, writeset);
1.317 djm 2384: else if (unpause_secs != NULL) {
2385: /*
2386: * Collect the time that the earliest
2387: * channel comes off pause.
2388: */
1.403 djm 2389: debug3_f("chan %d: skip for %d more "
2390: "seconds", c->self,
1.317 djm 2391: (int)(c->notbefore - now));
2392: if (*unpause_secs == 0 ||
2393: (c->notbefore - now) < *unpause_secs)
2394: *unpause_secs = c->notbefore - now;
2395: }
2396: }
1.367 djm 2397: channel_garbage_collect(ssh, c);
1.1 deraadt 2398: }
1.317 djm 2399: if (unpause_secs != NULL && *unpause_secs != 0)
1.403 djm 2400: debug3_f("first channel unpauses in %d seconds",
2401: (int)*unpause_secs);
1.1 deraadt 2402: }
2403:
1.121 markus 2404: /*
1.372 markus 2405: * Create sockets before allocating the select bitmasks.
2406: * This is necessary for things that need to happen after reading
2407: * the network-input but before channel_prepare_select().
2408: */
2409: static void
2410: channel_before_prepare_select(struct ssh *ssh)
2411: {
2412: struct ssh_channels *sc = ssh->chanctxt;
2413: Channel *c;
2414: u_int i, oalloc;
2415:
2416: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2417: c = sc->channels[i];
2418: if (c == NULL)
2419: continue;
2420: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
2421: channel_before_prepare_select_rdynamic(ssh, c);
2422: }
2423: }
2424:
2425: /*
1.121 markus 2426: * Allocate/update select bitmasks and add any bits relevant to channels in
2427: * select bitmasks.
2428: */
1.49 markus 2429: void
1.366 djm 2430: channel_prepare_select(struct ssh *ssh, fd_set **readsetp, fd_set **writesetp,
2431: int *maxfdp, u_int *nallocp, time_t *minwait_secs)
1.41 markus 2432: {
1.243 djm 2433: u_int n, sz, nfdset;
1.84 markus 2434:
1.372 markus 2435: channel_before_prepare_select(ssh); /* might update channel_max_fd */
2436:
1.367 djm 2437: n = MAXIMUM(*maxfdp, ssh->chanctxt->channel_max_fd);
1.84 markus 2438:
1.243 djm 2439: nfdset = howmany(n+1, NFDBITS);
2440: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2441: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2442: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2443: sz = nfdset * sizeof(fd_mask);
2444:
1.132 markus 2445: /* perhaps check sz < nalloc/2 and shrink? */
2446: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2447: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2448: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2449: *nallocp = sz;
1.84 markus 2450: }
1.132 markus 2451: *maxfdp = n;
1.84 markus 2452: memset(*readsetp, 0, sz);
2453: memset(*writesetp, 0, sz);
2454:
1.366 djm 2455: if (!ssh_packet_is_rekeying(ssh))
1.367 djm 2456: channel_handler(ssh, CHAN_PRE, *readsetp, *writesetp,
1.317 djm 2457: minwait_secs);
1.41 markus 2458: }
2459:
1.121 markus 2460: /*
2461: * After select, perform any appropriate operations for channels which have
2462: * events pending.
2463: */
1.49 markus 2464: void
1.366 djm 2465: channel_after_select(struct ssh *ssh, fd_set *readset, fd_set *writeset)
1.41 markus 2466: {
1.367 djm 2467: channel_handler(ssh, CHAN_POST, readset, writeset, NULL);
2468: }
2469:
2470: /*
2471: * Enqueue data for channels with open or draining c->input.
2472: */
2473: static void
2474: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2475: {
1.373 djm 2476: size_t len, plen;
2477: const u_char *pkt;
1.367 djm 2478: int r;
2479:
2480: if ((len = sshbuf_len(c->input)) == 0) {
2481: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2482: /*
2483: * input-buffer is empty and read-socket shutdown:
2484: * tell peer, that we will not send more data:
2485: * send IEOF.
2486: * hack for extended data: delay EOF if EFD still
2487: * in use.
2488: */
2489: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2490: debug2("channel %d: "
2491: "ibuf_empty delayed efd %d/(%zu)",
2492: c->self, c->efd, sshbuf_len(c->extended));
2493: else
2494: chan_ibuf_empty(ssh, c);
2495: }
2496: return;
2497: }
2498:
1.368 djm 2499: if (!c->have_remote_id)
1.403 djm 2500: fatal_f("channel %d: no remote id", c->self);
1.368 djm 2501:
1.367 djm 2502: if (c->datagram) {
2503: /* Check datagram will fit; drop if not */
1.373 djm 2504: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
1.403 djm 2505: fatal_fr(r, "channel %i: get datagram", c->self);
1.367 djm 2506: /*
2507: * XXX this does tail-drop on the datagram queue which is
2508: * usually suboptimal compared to head-drop. Better to have
2509: * backpressure at read time? (i.e. read + discard)
2510: */
1.373 djm 2511: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2512: debug("channel %d: datagram too big", c->self);
2513: return;
2514: }
2515: /* Enqueue it */
2516: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2517: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2518: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.403 djm 2519: (r = sshpkt_send(ssh)) != 0)
2520: fatal_fr(r, "channel %i: send datagram", c->self);
1.373 djm 2521: c->remote_window -= plen;
1.367 djm 2522: return;
2523: }
2524:
2525: /* Enqueue packet for buffered data. */
2526: if (len > c->remote_window)
2527: len = c->remote_window;
2528: if (len > c->remote_maxpacket)
2529: len = c->remote_maxpacket;
2530: if (len == 0)
2531: return;
2532: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2533: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2534: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
1.403 djm 2535: (r = sshpkt_send(ssh)) != 0)
2536: fatal_fr(r, "channel %i: send data", c->self);
1.367 djm 2537: if ((r = sshbuf_consume(c->input, len)) != 0)
1.403 djm 2538: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2539: c->remote_window -= len;
1.41 markus 2540: }
2541:
1.367 djm 2542: /*
2543: * Enqueue data for channels with open c->extended in read mode.
2544: */
2545: static void
2546: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2547: {
2548: size_t len;
2549: int r;
2550:
2551: if ((len = sshbuf_len(c->extended)) == 0)
2552: return;
2553:
2554: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2555: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2556: if (len > c->remote_window)
2557: len = c->remote_window;
2558: if (len > c->remote_maxpacket)
2559: len = c->remote_maxpacket;
2560: if (len == 0)
2561: return;
1.368 djm 2562: if (!c->have_remote_id)
1.403 djm 2563: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2564: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2565: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2566: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2567: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
1.403 djm 2568: (r = sshpkt_send(ssh)) != 0)
2569: fatal_fr(r, "channel %i: data", c->self);
1.367 djm 2570: if ((r = sshbuf_consume(c->extended, len)) != 0)
1.403 djm 2571: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2572: c->remote_window -= len;
2573: debug2("channel %d: sent ext data %zu", c->self, len);
2574: }
1.121 markus 2575:
1.84 markus 2576: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2577: void
1.367 djm 2578: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2579: {
1.367 djm 2580: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2581: Channel *c;
1.367 djm 2582: u_int i;
1.1 deraadt 2583:
1.367 djm 2584: for (i = 0; i < sc->channels_alloc; i++) {
2585: c = sc->channels[i];
1.113 markus 2586: if (c == NULL)
2587: continue;
1.37 markus 2588:
1.121 markus 2589: /*
2590: * We are only interested in channels that can have buffered
2591: * incoming data.
2592: */
1.358 djm 2593: if (c->type != SSH_CHANNEL_OPEN)
2594: continue;
2595: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2596: /* XXX is this true? */
1.367 djm 2597: debug3("channel %d: will not send data after close",
2598: c->self);
1.44 markus 2599: continue;
2600: }
1.25 markus 2601:
2602: /* Get the amount of buffered data for this channel. */
1.367 djm 2603: if (c->istate == CHAN_INPUT_OPEN ||
2604: c->istate == CHAN_INPUT_WAIT_DRAIN)
2605: channel_output_poll_input_open(ssh, c);
1.44 markus 2606: /* Send extended data, i.e. stderr */
1.358 djm 2607: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2608: c->extended_usage == CHAN_EXTENDED_READ)
2609: channel_output_poll_extended_read(ssh, c);
1.25 markus 2610: }
1.1 deraadt 2611: }
2612:
1.354 markus 2613: /* -- mux proxy support */
2614:
2615: /*
2616: * When multiplexing channel messages for mux clients we have to deal
2617: * with downstream messages from the mux client and upstream messages
2618: * from the ssh server:
2619: * 1) Handling downstream messages is straightforward and happens
2620: * in channel_proxy_downstream():
2621: * - We forward all messages (mostly) unmodified to the server.
2622: * - However, in order to route messages from upstream to the correct
2623: * downstream client, we have to replace the channel IDs used by the
2624: * mux clients with a unique channel ID because the mux clients might
2625: * use conflicting channel IDs.
2626: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2627: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2628: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2629: * with the newly allocated channel ID.
2630: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 2631: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 2632: * is then translated back to the original mux client ID.
2633: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2634: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2635: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2636: * downstream mux client are removed.
2637: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2638: * requires more work, because they are not addressed to a specific
2639: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2640: * out whether the request is addressed to the local client or a
2641: * specific downstream client based on the listen-address/port.
1.380 djm 2642: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 2643: * not supported as the matching session/channel cannot be identified
2644: * easily.
2645: */
2646:
2647: /*
2648: * receive packets from downstream mux clients:
2649: * channel callback fired on read from mux client, creates
2650: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2651: * on channel creation.
2652: */
2653: int
1.367 djm 2654: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2655: {
2656: Channel *c = NULL;
2657: struct sshbuf *original = NULL, *modified = NULL;
2658: const u_char *cp;
2659: char *ctype = NULL, *listen_host = NULL;
2660: u_char type;
2661: size_t have;
1.370 djm 2662: int ret = -1, r;
1.355 djm 2663: u_int id, remote_id, listen_port;
1.354 markus 2664:
1.367 djm 2665: /* sshbuf_dump(downstream->input, stderr); */
2666: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2667: != 0) {
1.403 djm 2668: error_fr(r, "parse");
1.354 markus 2669: return -1;
2670: }
2671: if (have < 2) {
1.403 djm 2672: error_f("short message");
1.354 markus 2673: return -1;
2674: }
2675: type = cp[1];
2676: /* skip padlen + type */
2677: cp += 2;
2678: have -= 2;
2679: if (ssh_packet_log_type(type))
1.403 djm 2680: debug3_f("channel %u: down->up: type %u",
1.354 markus 2681: downstream->self, type);
2682:
2683: switch (type) {
2684: case SSH2_MSG_CHANNEL_OPEN:
2685: if ((original = sshbuf_from(cp, have)) == NULL ||
2686: (modified = sshbuf_new()) == NULL) {
1.403 djm 2687: error_f("alloc");
1.354 markus 2688: goto out;
2689: }
2690: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2691: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 2692: error_fr(r, "parse");
1.354 markus 2693: goto out;
2694: }
1.367 djm 2695: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 2696: -1, -1, -1, 0, 0, 0, ctype, 1);
1.354 markus 2697: c->mux_ctx = downstream; /* point to mux client */
2698: c->mux_downstream_id = id; /* original downstream id */
2699: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2700: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2701: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 2702: error_fr(r, "compose");
1.367 djm 2703: channel_free(ssh, c);
1.354 markus 2704: goto out;
2705: }
2706: break;
2707: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2708: /*
2709: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2710: * need to parse 'remote_id' instead of 'ctype'.
2711: */
2712: if ((original = sshbuf_from(cp, have)) == NULL ||
2713: (modified = sshbuf_new()) == NULL) {
1.403 djm 2714: error_f("alloc");
1.354 markus 2715: goto out;
2716: }
2717: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2718: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 2719: error_fr(r, "parse");
1.354 markus 2720: goto out;
2721: }
1.367 djm 2722: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 2723: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
1.354 markus 2724: c->mux_ctx = downstream; /* point to mux client */
2725: c->mux_downstream_id = id;
2726: c->remote_id = remote_id;
1.368 djm 2727: c->have_remote_id = 1;
1.354 markus 2728: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2729: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2730: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 2731: error_fr(r, "compose");
1.367 djm 2732: channel_free(ssh, c);
1.354 markus 2733: goto out;
2734: }
2735: break;
2736: case SSH2_MSG_GLOBAL_REQUEST:
2737: if ((original = sshbuf_from(cp, have)) == NULL) {
1.403 djm 2738: error_f("alloc");
1.354 markus 2739: goto out;
2740: }
2741: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
1.403 djm 2742: error_fr(r, "parse");
1.354 markus 2743: goto out;
2744: }
2745: if (strcmp(ctype, "tcpip-forward") != 0) {
1.403 djm 2746: error_f("unsupported request %s", ctype);
1.354 markus 2747: goto out;
2748: }
2749: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2750: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2751: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
1.403 djm 2752: error_fr(r, "parse");
1.354 markus 2753: goto out;
2754: }
1.355 djm 2755: if (listen_port > 65535) {
1.403 djm 2756: error_f("tcpip-forward for %s: bad port %u",
2757: listen_host, listen_port);
1.355 djm 2758: goto out;
2759: }
1.354 markus 2760: /* Record that connection to this host/port is permitted. */
1.381 djm 2761: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 2762: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 2763: listen_host = NULL;
2764: break;
2765: case SSH2_MSG_CHANNEL_CLOSE:
2766: if (have < 4)
2767: break;
2768: remote_id = PEEK_U32(cp);
1.367 djm 2769: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 2770: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 2771: channel_free(ssh, c);
1.354 markus 2772: else
2773: c->flags |= CHAN_CLOSE_SENT;
2774: }
2775: break;
2776: }
2777: if (modified) {
2778: if ((r = sshpkt_start(ssh, type)) != 0 ||
2779: (r = sshpkt_putb(ssh, modified)) != 0 ||
2780: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2781: error_fr(r, "send");
1.354 markus 2782: goto out;
2783: }
2784: } else {
2785: if ((r = sshpkt_start(ssh, type)) != 0 ||
2786: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2787: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2788: error_fr(r, "send");
1.354 markus 2789: goto out;
2790: }
2791: }
2792: ret = 0;
2793: out:
2794: free(ctype);
2795: free(listen_host);
2796: sshbuf_free(original);
2797: sshbuf_free(modified);
2798: return ret;
2799: }
2800:
2801: /*
2802: * receive packets from upstream server and de-multiplex packets
2803: * to correct downstream:
2804: * implemented as a helper for channel input handlers,
2805: * replaces local (proxy) channel ID with downstream channel ID.
2806: */
2807: int
1.363 markus 2808: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 2809: {
2810: struct sshbuf *b = NULL;
2811: Channel *downstream;
2812: const u_char *cp = NULL;
2813: size_t len;
2814: int r;
2815:
2816: /*
2817: * When receiving packets from the peer we need to check whether we
2818: * need to forward the packets to the mux client. In this case we
1.380 djm 2819: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 2820: * so we can cleanup the channel.
2821: */
2822: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2823: return 0;
2824: if ((downstream = c->mux_ctx) == NULL)
2825: return 0;
2826: switch (type) {
2827: case SSH2_MSG_CHANNEL_CLOSE:
2828: case SSH2_MSG_CHANNEL_DATA:
2829: case SSH2_MSG_CHANNEL_EOF:
2830: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2831: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2832: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2833: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2834: case SSH2_MSG_CHANNEL_SUCCESS:
2835: case SSH2_MSG_CHANNEL_FAILURE:
2836: case SSH2_MSG_CHANNEL_REQUEST:
2837: break;
2838: default:
1.403 djm 2839: debug2_f("channel %u: unsupported type %u", c->self, type);
1.354 markus 2840: return 0;
2841: }
2842: if ((b = sshbuf_new()) == NULL) {
1.403 djm 2843: error_f("alloc reply");
1.354 markus 2844: goto out;
2845: }
2846: /* get remaining payload (after id) */
2847: cp = sshpkt_ptr(ssh, &len);
2848: if (cp == NULL) {
1.403 djm 2849: error_f("no packet");
1.354 markus 2850: goto out;
2851: }
2852: /* translate id and send to muxclient */
2853: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2854: (r = sshbuf_put_u8(b, type)) != 0 ||
2855: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2856: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 2857: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.403 djm 2858: error_fr(r, "compose muxclient");
1.354 markus 2859: goto out;
2860: }
2861: /* sshbuf_dump(b, stderr); */
2862: if (ssh_packet_log_type(type))
1.403 djm 2863: debug3_f("channel %u: up->down: type %u", c->self, type);
1.354 markus 2864: out:
2865: /* update state */
2866: switch (type) {
2867: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2868: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 2869: if (cp && len > 4) {
1.354 markus 2870: c->remote_id = PEEK_U32(cp);
1.368 djm 2871: c->have_remote_id = 1;
2872: }
1.354 markus 2873: break;
2874: case SSH2_MSG_CHANNEL_CLOSE:
2875: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 2876: channel_free(ssh, c);
1.354 markus 2877: else
2878: c->flags |= CHAN_CLOSE_RCVD;
2879: break;
2880: }
2881: sshbuf_free(b);
2882: return 1;
2883: }
1.121 markus 2884:
2885: /* -- protocol input */
1.249 djm 2886:
1.367 djm 2887: /* Parse a channel ID from the current packet */
2888: static int
2889: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
2890: {
2891: u_int32_t id;
2892: int r;
2893:
2894: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
1.403 djm 2895: error_r(r, "%s: parse id", where);
1.367 djm 2896: ssh_packet_disconnect(ssh, "Invalid %s message", what);
2897: }
2898: if (id > INT_MAX) {
1.403 djm 2899: error_r(r, "%s: bad channel id %u", where, id);
1.367 djm 2900: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
2901: }
2902: return (int)id;
2903: }
2904:
2905: /* Lookup a channel from an ID in the current packet */
2906: static Channel *
2907: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
2908: {
2909: int id = channel_parse_id(ssh, where, what);
2910: Channel *c;
2911:
2912: if ((c = channel_lookup(ssh, id)) == NULL) {
2913: ssh_packet_disconnect(ssh,
2914: "%s packet referred to nonexistent channel %d", what, id);
2915: }
2916: return c;
2917: }
2918:
1.339 markus 2919: int
1.363 markus 2920: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2921: {
1.332 djm 2922: const u_char *data;
1.367 djm 2923: size_t data_len, win_len;
2924: Channel *c = channel_from_packet_id(ssh, __func__, "data");
2925: int r;
1.25 markus 2926:
1.363 markus 2927: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2928: return 0;
1.25 markus 2929:
2930: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2931: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 2932: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
2933: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 2934: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2935: return 0;
1.37 markus 2936:
1.25 markus 2937: /* Get the data. */
1.389 djm 2938: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
2939: (r = sshpkt_get_end(ssh)) != 0)
1.403 djm 2940: fatal_fr(r, "channel %i: get data", c->self);
1.367 djm 2941:
1.309 djm 2942: win_len = data_len;
2943: if (c->datagram)
2944: win_len += 4; /* string length header */
1.200 markus 2945:
2946: /*
1.367 djm 2947: * The sending side reduces its window as it sends data, so we
2948: * must 'fake' consumption of the data in order to ensure that window
2949: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 2950: */
1.358 djm 2951: if (c->ostate != CHAN_OUTPUT_OPEN) {
2952: c->local_window -= win_len;
2953: c->local_consumed += win_len;
1.339 markus 2954: return 0;
1.200 markus 2955: }
1.41 markus 2956:
1.358 djm 2957: if (win_len > c->local_maxpacket) {
1.367 djm 2958: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 2959: c->self, win_len, c->local_maxpacket);
1.367 djm 2960: return 0;
1.358 djm 2961: }
2962: if (win_len > c->local_window) {
1.367 djm 2963: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 2964: c->self, win_len, c->local_window);
2965: return 0;
1.44 markus 2966: }
1.358 djm 2967: c->local_window -= win_len;
2968:
1.367 djm 2969: if (c->datagram) {
2970: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
1.403 djm 2971: fatal_fr(r, "channel %i: append datagram", c->self);
1.367 djm 2972: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
1.403 djm 2973: fatal_fr(r, "channel %i: append data", c->self);
1.367 djm 2974:
1.339 markus 2975: return 0;
1.1 deraadt 2976: }
1.121 markus 2977:
1.339 markus 2978: int
1.363 markus 2979: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 2980: {
1.367 djm 2981: const u_char *data;
2982: size_t data_len;
2983: u_int32_t tcode;
2984: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
2985: int r;
1.44 markus 2986:
1.363 markus 2987: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2988: return 0;
1.44 markus 2989: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 2990: logit("channel %d: ext data for non open", c->self);
1.339 markus 2991: return 0;
1.172 markus 2992: }
2993: if (c->flags & CHAN_EOF_RCVD) {
1.404 djm 2994: if (ssh->compat & SSH_BUG_EXTEOF)
1.367 djm 2995: debug("channel %d: accepting ext data after eof",
2996: c->self);
1.172 markus 2997: else
1.367 djm 2998: ssh_packet_disconnect(ssh, "Received extended_data "
2999: "after EOF on channel %d.", c->self);
3000: }
3001:
3002: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
1.403 djm 3003: error_fr(r, "parse tcode");
1.367 djm 3004: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3005: }
3006: if (c->efd == -1 ||
3007: c->extended_usage != CHAN_EXTENDED_WRITE ||
3008: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3009: logit("channel %d: bad ext data", c->self);
1.339 markus 3010: return 0;
1.44 markus 3011: }
1.389 djm 3012: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3013: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3014: error_fr(r, "parse data");
1.367 djm 3015: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3016: }
3017:
1.44 markus 3018: if (data_len > c->local_window) {
1.367 djm 3019: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3020: c->self, data_len, c->local_window);
1.339 markus 3021: return 0;
1.44 markus 3022: }
1.367 djm 3023: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3024: /* XXX sshpkt_getb? */
3025: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
1.403 djm 3026: error_fr(r, "append");
1.44 markus 3027: c->local_window -= data_len;
1.339 markus 3028: return 0;
1.44 markus 3029: }
3030:
1.339 markus 3031: int
1.363 markus 3032: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3033: {
1.367 djm 3034: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3035: int r;
1.367 djm 3036:
1.389 djm 3037: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3038: error_fr(r, "parse data");
1.389 djm 3039: ssh_packet_disconnect(ssh, "Invalid ieof message");
3040: }
1.41 markus 3041:
1.363 markus 3042: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3043: return 0;
1.367 djm 3044: chan_rcvd_ieof(ssh, c);
1.133 markus 3045:
3046: /* XXX force input close */
1.156 markus 3047: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3048: debug("channel %d: FORCE input drain", c->self);
3049: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3050: if (sshbuf_len(c->input) == 0)
3051: chan_ibuf_empty(ssh, c);
1.133 markus 3052: }
1.339 markus 3053: return 0;
1.41 markus 3054: }
1.1 deraadt 3055:
1.339 markus 3056: int
1.363 markus 3057: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3058: {
1.367 djm 3059: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3060: int r;
1.151 markus 3061:
1.363 markus 3062: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3063: return 0;
1.389 djm 3064: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3065: error_fr(r, "parse data");
1.389 djm 3066: ssh_packet_disconnect(ssh, "Invalid oclose message");
3067: }
1.367 djm 3068: chan_rcvd_oclose(ssh, c);
1.339 markus 3069: return 0;
1.1 deraadt 3070: }
3071:
1.339 markus 3072: int
1.363 markus 3073: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3074: {
1.367 djm 3075: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3076: u_int32_t remote_window, remote_maxpacket;
3077: int r;
1.25 markus 3078:
1.363 markus 3079: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3080: return 0;
3081: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3082: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3083: "non-opening channel %d.", c->self);
3084: /*
3085: * Record the remote channel number and mark that the channel
3086: * is now open.
3087: */
1.368 djm 3088: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3089: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3090: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3091: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3092: error_fr(r, "window/maxpacket");
1.389 djm 3093: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3094: }
3095:
1.368 djm 3096: c->have_remote_id = 1;
1.367 djm 3097: c->remote_window = remote_window;
3098: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3099: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3100: if (c->open_confirm) {
1.403 djm 3101: debug2_f("channel %d: callback start", c->self);
1.367 djm 3102: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
1.403 djm 3103: debug2_f("channel %d: callback done", c->self);
1.44 markus 3104: }
1.358 djm 3105: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3106: c->remote_window, c->remote_maxpacket);
1.339 markus 3107: return 0;
1.1 deraadt 3108: }
3109:
1.127 itojun 3110: static char *
1.114 markus 3111: reason2txt(int reason)
3112: {
1.143 deraadt 3113: switch (reason) {
1.114 markus 3114: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3115: return "administratively prohibited";
3116: case SSH2_OPEN_CONNECT_FAILED:
3117: return "connect failed";
3118: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3119: return "unknown channel type";
3120: case SSH2_OPEN_RESOURCE_SHORTAGE:
3121: return "resource shortage";
3122: }
1.117 stevesk 3123: return "unknown reason";
1.114 markus 3124: }
3125:
1.339 markus 3126: int
1.363 markus 3127: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3128: {
1.367 djm 3129: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3130: u_int32_t reason;
3131: char *msg = NULL;
3132: int r;
1.25 markus 3133:
1.363 markus 3134: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3135: return 0;
3136: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3137: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3138: "non-opening channel %d.", c->self);
3139: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
1.403 djm 3140: error_fr(r, "parse reason");
1.389 djm 3141: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3142: }
1.378 djm 3143: /* skip language */
3144: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3145: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3146: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3147: error_fr(r, "parse msg/lang");
1.389 djm 3148: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3149: }
1.367 djm 3150: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3151: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3152: free(msg);
3153: if (c->open_confirm) {
1.403 djm 3154: debug2_f("channel %d: callback start", c->self);
1.367 djm 3155: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
1.403 djm 3156: debug2_f("channel %d: callback done", c->self);
1.44 markus 3157: }
1.291 djm 3158: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3159: chan_mark_dead(ssh, c);
1.339 markus 3160: return 0;
1.44 markus 3161: }
3162:
1.339 markus 3163: int
1.363 markus 3164: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3165: {
1.367 djm 3166: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3167: Channel *c;
1.367 djm 3168: u_int32_t adjust;
3169: u_int new_rwin;
3170: int r;
1.1 deraadt 3171:
1.367 djm 3172: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3173: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3174: return 0;
1.372 markus 3175: }
1.367 djm 3176:
1.363 markus 3177: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3178: return 0;
1.389 djm 3179: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3180: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3181: error_fr(r, "parse adjust");
1.389 djm 3182: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3183: }
3184: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3185: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3186: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3187: c->self, adjust, c->remote_window);
3188: }
3189: c->remote_window = new_rwin;
1.339 markus 3190: return 0;
1.121 markus 3191: }
1.1 deraadt 3192:
1.339 markus 3193: int
1.363 markus 3194: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3195: {
1.367 djm 3196: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3197: Channel *c;
3198: struct channel_confirm *cc;
3199:
3200: /* Reset keepalive timeout */
1.389 djm 3201: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3202:
1.403 djm 3203: debug2_f("type %d id %d", type, id);
1.275 djm 3204:
1.367 djm 3205: if ((c = channel_lookup(ssh, id)) == NULL) {
1.403 djm 3206: logit_f("%d: unknown", id);
1.339 markus 3207: return 0;
1.367 djm 3208: }
1.363 markus 3209: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3210: return 0;
1.394 dtucker 3211: if (sshpkt_get_end(ssh) != 0)
1.389 djm 3212: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3213: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3214: return 0;
1.367 djm 3215: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3216: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 3217: freezero(cc, sizeof(*cc));
1.339 markus 3218: return 0;
1.275 djm 3219: }
1.121 markus 3220:
3221: /* -- tcp forwarding */
1.135 markus 3222:
3223: void
1.367 djm 3224: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3225: {
1.367 djm 3226: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3227: }
1.121 markus 3228:
1.312 djm 3229:
3230: /*
3231: * Determine whether or not a port forward listens to loopback, the
3232: * specified address or wildcard. On the client, a specified bind
3233: * address will always override gateway_ports. On the server, a
3234: * gateway_ports of 1 (``yes'') will override the client's specification
3235: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3236: * will bind to whatever address the client asked for.
3237: *
3238: * Special-case listen_addrs are:
3239: *
3240: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3241: * "" (empty string), "*" -> wildcard v4/v6
3242: * "localhost" -> loopback v4/v6
1.334 djm 3243: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3244: */
3245: static const char *
1.389 djm 3246: channel_fwd_bind_addr(struct ssh *ssh, const char *listen_addr, int *wildcardp,
1.336 millert 3247: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3248: {
3249: const char *addr = NULL;
3250: int wildcard = 0;
3251:
3252: if (listen_addr == NULL) {
3253: /* No address specified: default to gateway_ports setting */
1.336 millert 3254: if (fwd_opts->gateway_ports)
1.312 djm 3255: wildcard = 1;
1.336 millert 3256: } else if (fwd_opts->gateway_ports || is_client) {
1.404 djm 3257: if (((ssh->compat & SSH_OLD_FORWARD_ADDR) &&
1.312 djm 3258: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3259: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3260: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3261: wildcard = 1;
1.326 djm 3262: /*
3263: * Notify client if they requested a specific listen
3264: * address and it was overridden.
3265: */
3266: if (*listen_addr != '\0' &&
3267: strcmp(listen_addr, "0.0.0.0") != 0 &&
3268: strcmp(listen_addr, "*") != 0) {
1.389 djm 3269: ssh_packet_send_debug(ssh,
3270: "Forwarding listen address "
1.326 djm 3271: "\"%s\" overridden by server "
3272: "GatewayPorts", listen_addr);
3273: }
1.334 djm 3274: } else if (strcmp(listen_addr, "localhost") != 0 ||
3275: strcmp(listen_addr, "127.0.0.1") == 0 ||
3276: strcmp(listen_addr, "::1") == 0) {
1.395 djm 3277: /*
3278: * Accept explicit localhost address when
3279: * GatewayPorts=yes. The "localhost" hostname is
3280: * deliberately skipped here so it will listen on all
3281: * available local address families.
3282: */
1.334 djm 3283: addr = listen_addr;
1.326 djm 3284: }
1.334 djm 3285: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3286: strcmp(listen_addr, "::1") == 0) {
3287: /*
3288: * If a specific IPv4/IPv6 localhost address has been
3289: * requested then accept it even if gateway_ports is in
3290: * effect. This allows the client to prefer IPv4 or IPv6.
3291: */
3292: addr = listen_addr;
1.312 djm 3293: }
3294: if (wildcardp != NULL)
3295: *wildcardp = wildcard;
3296: return addr;
3297: }
3298:
1.160 markus 3299: static int
1.367 djm 3300: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3301: struct Forward *fwd, int *allocated_listen_port,
3302: struct ForwardOptions *fwd_opts)
1.25 markus 3303: {
1.113 markus 3304: Channel *c;
1.226 djm 3305: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3306: struct addrinfo hints, *ai, *aitop;
1.212 djm 3307: const char *host, *addr;
1.35 markus 3308: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3309: in_port_t *lport_p;
1.25 markus 3310:
1.212 djm 3311: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3312:
1.344 millert 3313: if (is_client && fwd->connect_path != NULL) {
3314: host = fwd->connect_path;
3315: } else {
3316: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3317: fwd->listen_host : fwd->connect_host;
3318: if (host == NULL) {
3319: error("No forward host name.");
3320: return 0;
3321: }
3322: if (strlen(host) >= NI_MAXHOST) {
3323: error("Forward host name too long.");
3324: return 0;
3325: }
1.87 markus 3326: }
1.25 markus 3327:
1.312 djm 3328: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3329: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3330: is_client, fwd_opts);
1.403 djm 3331: debug3_f("type %d wildcard %d addr %s", type, wildcard,
3332: (addr == NULL) ? "NULL" : addr);
1.212 djm 3333:
3334: /*
1.35 markus 3335: * getaddrinfo returns a loopback address if the hostname is
3336: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3337: */
1.35 markus 3338: memset(&hints, 0, sizeof(hints));
1.367 djm 3339: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3340: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3341: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3342: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3343: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3344: if (addr == NULL) {
3345: /* This really shouldn't happen */
1.389 djm 3346: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3347: ssh_gai_strerror(r));
1.212 djm 3348: } else {
1.403 djm 3349: error_f("getaddrinfo(%.64s): %s", addr,
1.271 dtucker 3350: ssh_gai_strerror(r));
1.212 djm 3351: }
1.218 markus 3352: return 0;
1.212 djm 3353: }
1.295 djm 3354: if (allocated_listen_port != NULL)
3355: *allocated_listen_port = 0;
1.35 markus 3356: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3357: switch (ai->ai_family) {
3358: case AF_INET:
3359: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3360: sin_port;
3361: break;
3362: case AF_INET6:
3363: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3364: sin6_port;
3365: break;
3366: default:
1.35 markus 3367: continue;
1.295 djm 3368: }
3369: /*
3370: * If allocating a port for -R forwards, then use the
3371: * same port for all address families.
3372: */
1.367 djm 3373: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3374: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3375: *allocated_listen_port > 0)
1.295 djm 3376: *lport_p = htons(*allocated_listen_port);
3377:
1.35 markus 3378: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3379: strport, sizeof(strport),
3380: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.403 djm 3381: error_f("getnameinfo failed");
1.35 markus 3382: continue;
3383: }
3384: /* Create a port to listen for the host. */
1.300 dtucker 3385: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 3386: if (sock == -1) {
1.35 markus 3387: /* this is no error since kernel may not support ipv6 */
1.377 djm 3388: verbose("socket [%s]:%s: %.100s", ntop, strport,
3389: strerror(errno));
1.35 markus 3390: continue;
3391: }
1.226 djm 3392:
1.376 djm 3393: set_reuseaddr(sock);
1.182 stevesk 3394:
1.295 djm 3395: debug("Local forwarding listening on %s port %s.",
3396: ntop, strport);
1.35 markus 3397:
3398: /* Bind the socket to the address. */
1.393 deraadt 3399: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3400: /*
3401: * address can be in if use ipv6 address is
3402: * already bound
3403: */
1.377 djm 3404: verbose("bind [%s]:%s: %.100s",
3405: ntop, strport, strerror(errno));
1.35 markus 3406: close(sock);
3407: continue;
3408: }
3409: /* Start listening for connections on the socket. */
1.393 deraadt 3410: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3411: error("listen [%s]:%s: %.100s", ntop, strport,
3412: strerror(errno));
1.35 markus 3413: close(sock);
3414: continue;
3415: }
1.295 djm 3416:
3417: /*
1.336 millert 3418: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3419: * record what we got.
3420: */
1.367 djm 3421: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3422: fwd->listen_port == 0 &&
1.295 djm 3423: allocated_listen_port != NULL &&
3424: *allocated_listen_port == 0) {
1.350 djm 3425: *allocated_listen_port = get_local_port(sock);
1.295 djm 3426: debug("Allocated listen port %d",
3427: *allocated_listen_port);
3428: }
3429:
1.35 markus 3430: /* Allocate a channel number for the socket. */
1.367 djm 3431: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3432: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3433: 0, "port listener", 1);
1.293 djm 3434: c->path = xstrdup(host);
1.336 millert 3435: c->host_port = fwd->connect_port;
1.312 djm 3436: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3437: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.404 djm 3438: !(ssh->compat & SSH_BUG_DYNAMIC_RPORT))
1.315 markus 3439: c->listening_port = *allocated_listen_port;
3440: else
1.336 millert 3441: c->listening_port = fwd->listen_port;
1.35 markus 3442: success = 1;
3443: }
3444: if (success == 0)
1.403 djm 3445: error_f("cannot listen to port: %d", fwd->listen_port);
1.35 markus 3446: freeaddrinfo(aitop);
1.87 markus 3447: return success;
1.25 markus 3448: }
1.1 deraadt 3449:
1.336 millert 3450: static int
1.367 djm 3451: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3452: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3453: {
3454: struct sockaddr_un sunaddr;
3455: const char *path;
3456: Channel *c;
3457: int port, sock;
3458: mode_t omask;
3459:
3460: switch (type) {
3461: case SSH_CHANNEL_UNIX_LISTENER:
3462: if (fwd->connect_path != NULL) {
3463: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3464: error("Local connecting path too long: %s",
3465: fwd->connect_path);
3466: return 0;
3467: }
3468: path = fwd->connect_path;
3469: port = PORT_STREAMLOCAL;
3470: } else {
3471: if (fwd->connect_host == NULL) {
3472: error("No forward host name.");
3473: return 0;
3474: }
3475: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3476: error("Forward host name too long.");
3477: return 0;
3478: }
3479: path = fwd->connect_host;
3480: port = fwd->connect_port;
3481: }
3482: break;
3483: case SSH_CHANNEL_RUNIX_LISTENER:
3484: path = fwd->listen_path;
3485: port = PORT_STREAMLOCAL;
3486: break;
3487: default:
1.403 djm 3488: error_f("unexpected channel type %d", type);
1.336 millert 3489: return 0;
3490: }
3491:
3492: if (fwd->listen_path == NULL) {
3493: error("No forward path name.");
3494: return 0;
3495: }
3496: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3497: error("Local listening path too long: %s", fwd->listen_path);
3498: return 0;
3499: }
3500:
1.403 djm 3501: debug3_f("type %d path %s", type, fwd->listen_path);
1.336 millert 3502:
3503: /* Start a Unix domain listener. */
3504: omask = umask(fwd_opts->streamlocal_bind_mask);
3505: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3506: fwd_opts->streamlocal_bind_unlink);
3507: umask(omask);
3508: if (sock < 0)
3509: return 0;
3510:
3511: debug("Local forwarding listening on path %s.", fwd->listen_path);
3512:
3513: /* Allocate a channel number for the socket. */
1.367 djm 3514: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3515: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3516: 0, "unix listener", 1);
3517: c->path = xstrdup(path);
3518: c->host_port = port;
3519: c->listening_port = PORT_STREAMLOCAL;
3520: c->listening_addr = xstrdup(fwd->listen_path);
3521: return 1;
3522: }
3523:
3524: static int
1.367 djm 3525: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3526: const char *host, u_short port)
1.202 djm 3527: {
1.209 avsm 3528: u_int i;
3529: int found = 0;
1.202 djm 3530:
1.367 djm 3531: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3532: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3533: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3534: continue;
3535: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
1.403 djm 3536: debug2_f("close channel %d", i);
1.367 djm 3537: channel_free(ssh, c);
1.312 djm 3538: found = 1;
3539: }
3540: }
3541:
1.367 djm 3542: return found;
1.312 djm 3543: }
3544:
1.336 millert 3545: static int
1.367 djm 3546: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3547: {
3548: u_int i;
3549: int found = 0;
3550:
1.367 djm 3551: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3552: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3553: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3554: continue;
3555: if (c->path == NULL)
3556: continue;
3557: if (strcmp(c->path, path) == 0) {
1.403 djm 3558: debug2_f("close channel %d", i);
1.367 djm 3559: channel_free(ssh, c);
1.336 millert 3560: found = 1;
3561: }
3562: }
3563:
1.367 djm 3564: return found;
1.336 millert 3565: }
3566:
1.312 djm 3567: int
1.367 djm 3568: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3569: {
1.367 djm 3570: if (fwd->listen_path != NULL) {
3571: return channel_cancel_rport_listener_streamlocal(ssh,
3572: fwd->listen_path);
3573: } else {
3574: return channel_cancel_rport_listener_tcpip(ssh,
3575: fwd->listen_host, fwd->listen_port);
3576: }
1.336 millert 3577: }
3578:
3579: static int
1.367 djm 3580: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3581: const char *lhost, u_short lport, int cport,
3582: struct ForwardOptions *fwd_opts)
1.312 djm 3583: {
3584: u_int i;
3585: int found = 0;
1.389 djm 3586: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 3587:
1.367 djm 3588: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3589: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3590: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3591: continue;
1.313 markus 3592: if (c->listening_port != lport)
1.312 djm 3593: continue;
1.313 markus 3594: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3595: /* skip dynamic forwardings */
3596: if (c->host_port == 0)
3597: continue;
3598: } else {
3599: if (c->host_port != cport)
3600: continue;
3601: }
1.312 djm 3602: if ((c->listening_addr == NULL && addr != NULL) ||
3603: (c->listening_addr != NULL && addr == NULL))
3604: continue;
3605: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.403 djm 3606: debug2_f("close channel %d", i);
1.367 djm 3607: channel_free(ssh, c);
1.202 djm 3608: found = 1;
3609: }
3610: }
3611:
1.367 djm 3612: return found;
1.202 djm 3613: }
3614:
1.336 millert 3615: static int
1.367 djm 3616: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3617: {
3618: u_int i;
3619: int found = 0;
3620:
3621: if (path == NULL) {
1.403 djm 3622: error_f("no path specified.");
1.336 millert 3623: return 0;
3624: }
3625:
1.367 djm 3626: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3627: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3628: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3629: continue;
3630: if (c->listening_addr == NULL)
3631: continue;
3632: if (strcmp(c->listening_addr, path) == 0) {
1.403 djm 3633: debug2_f("close channel %d", i);
1.367 djm 3634: channel_free(ssh, c);
1.336 millert 3635: found = 1;
3636: }
3637: }
3638:
1.367 djm 3639: return found;
1.336 millert 3640: }
3641:
3642: int
1.367 djm 3643: channel_cancel_lport_listener(struct ssh *ssh,
3644: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3645: {
1.367 djm 3646: if (fwd->listen_path != NULL) {
3647: return channel_cancel_lport_listener_streamlocal(ssh,
3648: fwd->listen_path);
3649: } else {
3650: return channel_cancel_lport_listener_tcpip(ssh,
3651: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3652: }
1.336 millert 3653: }
3654:
1.362 markus 3655: /* protocol local port fwd, used by ssh */
1.160 markus 3656: int
1.367 djm 3657: channel_setup_local_fwd_listener(struct ssh *ssh,
3658: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3659: {
1.336 millert 3660: if (fwd->listen_path != NULL) {
1.367 djm 3661: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3662: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3663: } else {
1.367 djm 3664: return channel_setup_fwd_listener_tcpip(ssh,
3665: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3666: }
1.160 markus 3667: }
3668:
1.381 djm 3669: /* Matches a remote forwarding permission against a requested forwarding */
3670: static int
3671: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
3672: {
3673: int ret;
3674: char *lhost;
3675:
3676: /* XXX add ACLs for streamlocal */
3677: if (fwd->listen_path != NULL)
3678: return 1;
3679:
3680: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
3681: return 0;
3682:
3683: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
3684: allowed_open->listen_port != fwd->listen_port)
3685: return 0;
3686:
3687: /* Match hostnames case-insensitively */
3688: lhost = xstrdup(fwd->listen_host);
3689: lowercase(lhost);
3690: ret = match_pattern(lhost, allowed_open->listen_host);
3691: free(lhost);
3692:
3693: return ret;
3694: }
3695:
3696: /* Checks whether a requested remote forwarding is permitted */
3697: static int
3698: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
3699: {
3700: struct ssh_channels *sc = ssh->chanctxt;
3701: struct permission_set *pset = &sc->remote_perms;
3702: u_int i, permit, permit_adm = 1;
3703: struct permission *perm;
3704:
3705: /* XXX apply GatewayPorts override before checking? */
3706:
3707: permit = pset->all_permitted;
3708: if (!permit) {
3709: for (i = 0; i < pset->num_permitted_user; i++) {
3710: perm = &pset->permitted_user[i];
3711: if (remote_open_match(perm, fwd)) {
3712: permit = 1;
3713: break;
3714: }
3715: }
3716: }
3717:
3718: if (pset->num_permitted_admin > 0) {
3719: permit_adm = 0;
3720: for (i = 0; i < pset->num_permitted_admin; i++) {
3721: perm = &pset->permitted_admin[i];
3722: if (remote_open_match(perm, fwd)) {
3723: permit_adm = 1;
3724: break;
3725: }
3726: }
3727: }
3728:
3729: return permit && permit_adm;
3730: }
3731:
1.160 markus 3732: /* protocol v2 remote port fwd, used by sshd */
3733: int
1.367 djm 3734: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3735: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3736: {
1.381 djm 3737: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 3738: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 3739: if (fwd->listen_path != NULL)
3740: /* XXX always allowed, see remote_open_match() */
3741: logit("Received request from %.100s port %d to "
3742: "remote forward to path \"%.100s\", "
3743: "but the request was denied.",
3744: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3745: fwd->listen_path);
3746: else if(fwd->listen_host != NULL)
3747: logit("Received request from %.100s port %d to "
3748: "remote forward to host %.100s port %d, "
3749: "but the request was denied.",
3750: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3751: fwd->listen_host, fwd->listen_port );
3752: else
3753: logit("Received request from %.100s port %d to remote "
3754: "forward, but the request was denied.",
3755: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 3756: return 0;
3757: }
1.336 millert 3758: if (fwd->listen_path != NULL) {
1.367 djm 3759: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3760: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3761: } else {
1.367 djm 3762: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 3763: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3764: fwd_opts);
3765: }
1.160 markus 3766: }
3767:
1.27 markus 3768: /*
1.312 djm 3769: * Translate the requested rfwd listen host to something usable for
3770: * this server.
3771: */
3772: static const char *
3773: channel_rfwd_bind_host(const char *listen_host)
3774: {
3775: if (listen_host == NULL) {
1.378 djm 3776: return "localhost";
1.312 djm 3777: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 3778: return "";
1.312 djm 3779: } else
3780: return listen_host;
3781: }
3782:
3783: /*
1.27 markus 3784: * Initiate forwarding of connections to port "port" on remote host through
3785: * the secure channel to host:port from local side.
1.315 markus 3786: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 3787: * channel_update_permission().
1.27 markus 3788: */
1.253 markus 3789: int
1.367 djm 3790: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 3791: {
1.367 djm 3792: int r, success = 0, idx = -1;
3793: char *host_to_connect, *listen_host, *listen_path;
3794: int port_to_connect, listen_port;
1.73 markus 3795:
1.25 markus 3796: /* Send the forward request to the remote side. */
1.358 djm 3797: if (fwd->listen_path != NULL) {
1.367 djm 3798: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3799: (r = sshpkt_put_cstring(ssh,
3800: "streamlocal-forward@openssh.com")) != 0 ||
3801: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3802: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3803: (r = sshpkt_send(ssh)) != 0 ||
3804: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 3805: fatal_fr(r, "request streamlocal");
1.336 millert 3806: } else {
1.367 djm 3807: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3808: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
3809: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3810: (r = sshpkt_put_cstring(ssh,
3811: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
3812: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
3813: (r = sshpkt_send(ssh)) != 0 ||
3814: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 3815: fatal_fr(r, "request tcpip-forward");
1.73 markus 3816: }
1.358 djm 3817: /* Assume that server accepts the request */
3818: success = 1;
1.73 markus 3819: if (success) {
1.305 djm 3820: /* Record that connection to this host/port is permitted. */
1.367 djm 3821: host_to_connect = listen_host = listen_path = NULL;
3822: port_to_connect = listen_port = 0;
1.336 millert 3823: if (fwd->connect_path != NULL) {
1.367 djm 3824: host_to_connect = xstrdup(fwd->connect_path);
3825: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 3826: } else {
1.367 djm 3827: host_to_connect = xstrdup(fwd->connect_host);
3828: port_to_connect = fwd->connect_port;
1.336 millert 3829: }
3830: if (fwd->listen_path != NULL) {
1.367 djm 3831: listen_path = xstrdup(fwd->listen_path);
3832: listen_port = PORT_STREAMLOCAL;
1.336 millert 3833: } else {
1.367 djm 3834: if (fwd->listen_host != NULL)
3835: listen_host = xstrdup(fwd->listen_host);
3836: listen_port = fwd->listen_port;
3837: }
1.381 djm 3838: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 3839: host_to_connect, port_to_connect,
3840: listen_host, listen_path, listen_port, NULL);
1.44 markus 3841: }
1.367 djm 3842: return idx;
1.1 deraadt 3843: }
3844:
1.333 markus 3845: static int
1.381 djm 3846: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 3847: int requestedport)
1.333 markus 3848: {
3849: if (allowed_open->host_to_connect == NULL)
3850: return 0;
3851: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3852: allowed_open->port_to_connect != requestedport)
3853: return 0;
1.351 dtucker 3854: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3855: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3856: return 0;
3857: return 1;
3858: }
3859:
3860: /*
1.336 millert 3861: * Note that in the listen host/port case
1.333 markus 3862: * we don't support FWD_PERMIT_ANY_PORT and
3863: * need to translate between the configured-host (listen_host)
3864: * and what we've sent to the remote server (channel_rfwd_bind_host)
3865: */
3866: static int
1.381 djm 3867: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 3868: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3869: {
3870: const char *allowed_host;
3871:
3872: if (allowed_open->host_to_connect == NULL)
3873: return 0;
3874: if (allowed_open->listen_port != requestedport)
3875: return 0;
1.335 djm 3876: if (!translate && allowed_open->listen_host == NULL &&
3877: requestedhost == NULL)
3878: return 1;
1.333 markus 3879: allowed_host = translate ?
3880: channel_rfwd_bind_host(allowed_open->listen_host) :
3881: allowed_open->listen_host;
1.382 djm 3882: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 3883: strcmp(allowed_host, requestedhost) != 0)
3884: return 0;
3885: return 1;
3886: }
3887:
1.336 millert 3888: static int
1.381 djm 3889: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 3890: const char *requestedpath)
3891: {
3892: if (allowed_open->host_to_connect == NULL)
3893: return 0;
3894: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3895: return 0;
3896: if (allowed_open->listen_path == NULL ||
3897: strcmp(allowed_open->listen_path, requestedpath) != 0)
3898: return 0;
3899: return 1;
3900: }
3901:
1.27 markus 3902: /*
1.208 deraadt 3903: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3904: * local side.
3905: */
1.336 millert 3906: static int
1.367 djm 3907: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
3908: const char *host, u_short port)
1.202 djm 3909: {
1.367 djm 3910: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 3911: struct permission_set *pset = &sc->local_perms;
1.367 djm 3912: int r;
3913: u_int i;
1.397 markus 3914: struct permission *perm = NULL;
1.202 djm 3915:
1.381 djm 3916: for (i = 0; i < pset->num_permitted_user; i++) {
3917: perm = &pset->permitted_user[i];
3918: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 3919: break;
1.381 djm 3920: perm = NULL;
1.202 djm 3921: }
1.381 djm 3922: if (perm == NULL) {
1.403 djm 3923: debug_f("requested forward not found");
1.312 djm 3924: return -1;
1.202 djm 3925: }
1.367 djm 3926: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3927: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
3928: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3929: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
3930: (r = sshpkt_put_u32(ssh, port)) != 0 ||
3931: (r = sshpkt_send(ssh)) != 0)
1.403 djm 3932: fatal_fr(r, "send cancel");
1.367 djm 3933:
1.381 djm 3934: fwd_perm_clear(perm); /* unregister */
1.336 millert 3935:
3936: return 0;
3937: }
3938:
3939: /*
3940: * Request cancellation of remote forwarding of Unix domain socket
3941: * path from local side.
3942: */
3943: static int
1.367 djm 3944: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3945: {
1.367 djm 3946: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 3947: struct permission_set *pset = &sc->local_perms;
1.367 djm 3948: int r;
3949: u_int i;
1.397 markus 3950: struct permission *perm = NULL;
1.336 millert 3951:
1.381 djm 3952: for (i = 0; i < pset->num_permitted_user; i++) {
3953: perm = &pset->permitted_user[i];
3954: if (open_listen_match_streamlocal(perm, path))
1.336 millert 3955: break;
1.381 djm 3956: perm = NULL;
1.336 millert 3957: }
1.381 djm 3958: if (perm == NULL) {
1.403 djm 3959: debug_f("requested forward not found");
1.336 millert 3960: return -1;
3961: }
1.367 djm 3962: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3963: (r = sshpkt_put_cstring(ssh,
3964: "cancel-streamlocal-forward@openssh.com")) != 0 ||
3965: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3966: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
3967: (r = sshpkt_send(ssh)) != 0)
1.403 djm 3968: fatal_fr(r, "send cancel");
1.367 djm 3969:
1.381 djm 3970: fwd_perm_clear(perm); /* unregister */
1.312 djm 3971:
3972: return 0;
1.202 djm 3973: }
3974:
3975: /*
1.336 millert 3976: * Request cancellation of remote forwarding of a connection from local side.
3977: */
3978: int
1.367 djm 3979: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3980: {
3981: if (fwd->listen_path != NULL) {
1.367 djm 3982: return channel_request_rforward_cancel_streamlocal(ssh,
3983: fwd->listen_path);
1.336 millert 3984: } else {
1.367 djm 3985: return channel_request_rforward_cancel_tcpip(ssh,
3986: fwd->listen_host,
3987: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 3988: }
1.1 deraadt 3989: }
3990:
1.99 markus 3991: /*
1.381 djm 3992: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 3993: * usually called by the server, because the user could connect to any port
3994: * anyway, and the server has no way to know but to trust the client anyway.
3995: */
3996: void
1.381 djm 3997: channel_permit_all(struct ssh *ssh, int where)
3998: {
3999: struct permission_set *pset = permission_set_get(ssh, where);
4000:
4001: if (pset->num_permitted_user == 0)
4002: pset->all_permitted = 1;
4003: }
4004:
4005: /*
4006: * Permit the specified host/port for forwarding.
4007: */
4008: void
4009: channel_add_permission(struct ssh *ssh, int who, int where,
4010: char *host, int port)
4011: {
4012: int local = where == FORWARD_LOCAL;
4013: struct permission_set *pset = permission_set_get(ssh, where);
4014:
4015: debug("allow %s forwarding to host %s port %d",
4016: fwd_ident(who, where), host, port);
4017: /*
4018: * Remote forwards set listen_host/port, local forwards set
4019: * host/port_to_connect.
4020: */
4021: permission_set_add(ssh, who, where,
4022: local ? host : 0, local ? port : 0,
4023: local ? NULL : host, NULL, local ? 0 : port, NULL);
4024: pset->all_permitted = 0;
4025: }
4026:
4027: /*
4028: * Administratively disable forwarding.
4029: */
4030: void
4031: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4032: {
1.381 djm 4033: channel_clear_permission(ssh, FORWARD_ADM, where);
4034: permission_set_add(ssh, FORWARD_ADM, where,
4035: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4036: }
4037:
1.381 djm 4038: /*
4039: * Clear a list of permitted opens.
4040: */
1.101 markus 4041: void
1.381 djm 4042: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4043: {
1.381 djm 4044: struct permission **permp;
4045: u_int *npermp;
1.367 djm 4046:
1.381 djm 4047: permission_set_get_array(ssh, who, where, &permp, &npermp);
4048: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4049: *npermp = 0;
1.315 markus 4050: }
4051:
4052: /*
4053: * Update the listen port for a dynamic remote forward, after
4054: * the actual 'newport' has been allocated. If 'newport' < 0 is
4055: * passed then they entry will be invalidated.
4056: */
4057: void
1.381 djm 4058: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4059: {
1.381 djm 4060: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4061:
1.381 djm 4062: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
1.403 djm 4063: debug_f("index out of range: %d num_permitted_user %d",
4064: idx, pset->num_permitted_user);
1.315 markus 4065: return;
4066: }
4067: debug("%s allowed port %d for forwarding to host %s port %d",
4068: newport > 0 ? "Updating" : "Removing",
4069: newport,
1.381 djm 4070: pset->permitted_user[idx].host_to_connect,
4071: pset->permitted_user[idx].port_to_connect);
1.367 djm 4072: if (newport <= 0)
1.381 djm 4073: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4074: else {
1.381 djm 4075: pset->permitted_user[idx].listen_port =
1.404 djm 4076: (ssh->compat & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
1.315 markus 4077: }
1.99 markus 4078: }
4079:
1.314 dtucker 4080: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4081: int
4082: permitopen_port(const char *p)
4083: {
4084: int port;
4085:
4086: if (strcmp(p, "*") == 0)
4087: return FWD_PERMIT_ANY_PORT;
4088: if ((port = a2port(p)) > 0)
4089: return port;
4090: return -1;
4091: }
4092:
1.276 djm 4093: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4094: static int
1.276 djm 4095: connect_next(struct channel_connect *cctx)
1.41 markus 4096: {
1.276 djm 4097: int sock, saved_errno;
1.336 millert 4098: struct sockaddr_un *sunaddr;
1.367 djm 4099: char ntop[NI_MAXHOST];
4100: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4101:
1.276 djm 4102: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4103: switch (cctx->ai->ai_family) {
4104: case AF_UNIX:
4105: /* unix:pathname instead of host:port */
4106: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4107: strlcpy(ntop, "unix", sizeof(ntop));
4108: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4109: break;
4110: case AF_INET:
4111: case AF_INET6:
4112: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4113: ntop, sizeof(ntop), strport, sizeof(strport),
4114: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
4115: error("connect_next: getnameinfo failed");
4116: continue;
4117: }
4118: break;
4119: default:
1.41 markus 4120: continue;
4121: }
1.300 dtucker 4122: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4123: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4124: if (cctx->ai->ai_next == NULL)
1.186 djm 4125: error("socket: %.100s", strerror(errno));
4126: else
4127: verbose("socket: %.100s", strerror(errno));
1.41 markus 4128: continue;
4129: }
1.205 djm 4130: if (set_nonblock(sock) == -1)
1.403 djm 4131: fatal_f("set_nonblock(%d)", sock);
1.276 djm 4132: if (connect(sock, cctx->ai->ai_addr,
4133: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
4134: debug("connect_next: host %.100s ([%.100s]:%s): "
4135: "%.100s", cctx->host, ntop, strport,
1.41 markus 4136: strerror(errno));
1.276 djm 4137: saved_errno = errno;
1.41 markus 4138: close(sock);
1.276 djm 4139: errno = saved_errno;
1.89 stevesk 4140: continue; /* fail -- try next */
1.41 markus 4141: }
1.336 millert 4142: if (cctx->ai->ai_family != AF_UNIX)
4143: set_nodelay(sock);
1.276 djm 4144: debug("connect_next: host %.100s ([%.100s]:%s) "
4145: "in progress, fd=%d", cctx->host, ntop, strport, sock);
4146: cctx->ai = cctx->ai->ai_next;
4147: return sock;
4148: }
4149: return -1;
4150: }
1.41 markus 4151:
1.276 djm 4152: static void
4153: channel_connect_ctx_free(struct channel_connect *cctx)
4154: {
1.321 djm 4155: free(cctx->host);
1.336 millert 4156: if (cctx->aitop) {
4157: if (cctx->aitop->ai_family == AF_UNIX)
4158: free(cctx->aitop);
4159: else
4160: freeaddrinfo(cctx->aitop);
4161: }
1.329 tedu 4162: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4163: }
4164:
1.357 dtucker 4165: /*
1.372 markus 4166: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4167: * passing back the failure reason if appropriate.
4168: */
1.372 markus 4169: static int
4170: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4171: char *ctype, char *rname, struct channel_connect *cctx,
4172: int *reason, const char **errmsg)
1.276 djm 4173: {
4174: struct addrinfo hints;
4175: int gaierr;
4176: int sock = -1;
4177: char strport[NI_MAXSERV];
1.336 millert 4178:
4179: if (port == PORT_STREAMLOCAL) {
4180: struct sockaddr_un *sunaddr;
4181: struct addrinfo *ai;
4182:
4183: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4184: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4185: return -1;
1.336 millert 4186: }
4187:
4188: /*
4189: * Fake up a struct addrinfo for AF_UNIX connections.
4190: * channel_connect_ctx_free() must check ai_family
4191: * and use free() not freeaddirinfo() for AF_UNIX.
4192: */
4193: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4194: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4195: ai->ai_addr = (struct sockaddr *)(ai + 1);
4196: ai->ai_addrlen = sizeof(*sunaddr);
4197: ai->ai_family = AF_UNIX;
1.372 markus 4198: ai->ai_socktype = socktype;
1.336 millert 4199: ai->ai_protocol = PF_UNSPEC;
4200: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4201: sunaddr->sun_family = AF_UNIX;
4202: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4203: cctx->aitop = ai;
1.336 millert 4204: } else {
4205: memset(&hints, 0, sizeof(hints));
1.367 djm 4206: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4207: hints.ai_socktype = socktype;
1.336 millert 4208: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4209: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4210: != 0) {
4211: if (errmsg != NULL)
4212: *errmsg = ssh_gai_strerror(gaierr);
4213: if (reason != NULL)
4214: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4215: error("connect_to %.100s: unknown host (%s)", name,
4216: ssh_gai_strerror(gaierr));
1.372 markus 4217: return -1;
1.336 millert 4218: }
1.41 markus 4219: }
1.276 djm 4220:
1.372 markus 4221: cctx->host = xstrdup(name);
4222: cctx->port = port;
4223: cctx->ai = cctx->aitop;
1.276 djm 4224:
1.372 markus 4225: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4226: error("connect to %.100s port %d failed: %s",
1.336 millert 4227: name, port, strerror(errno));
1.372 markus 4228: return -1;
4229: }
4230:
4231: return sock;
4232: }
4233:
4234: /* Return CONNECTING channel to remote host:port or local socket path */
4235: static Channel *
4236: connect_to(struct ssh *ssh, const char *host, int port,
4237: char *ctype, char *rname)
4238: {
4239: struct channel_connect cctx;
4240: Channel *c;
4241: int sock;
4242:
4243: memset(&cctx, 0, sizeof(cctx));
4244: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4245: &cctx, NULL, NULL);
4246: if (sock == -1) {
1.276 djm 4247: channel_connect_ctx_free(&cctx);
4248: return NULL;
1.41 markus 4249: }
1.367 djm 4250: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4251: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4252: c->host_port = port;
4253: c->path = xstrdup(host);
1.276 djm 4254: c->connect_ctx = cctx;
1.372 markus 4255:
1.276 djm 4256: return c;
1.41 markus 4257: }
1.99 markus 4258:
1.354 markus 4259: /*
4260: * returns either the newly connected channel or the downstream channel
4261: * that needs to deal with this connection.
4262: */
1.276 djm 4263: Channel *
1.367 djm 4264: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4265: u_short listen_port, char *ctype, char *rname)
1.73 markus 4266: {
1.367 djm 4267: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4268: struct permission_set *pset = &sc->local_perms;
1.367 djm 4269: u_int i;
1.381 djm 4270: struct permission *perm;
1.99 markus 4271:
1.381 djm 4272: for (i = 0; i < pset->num_permitted_user; i++) {
4273: perm = &pset->permitted_user[i];
4274: if (open_listen_match_tcpip(perm,
4275: listen_host, listen_port, 1)) {
4276: if (perm->downstream)
4277: return perm->downstream;
4278: if (perm->port_to_connect == 0)
1.372 markus 4279: return rdynamic_connect_prepare(ssh,
4280: ctype, rname);
1.367 djm 4281: return connect_to(ssh,
1.381 djm 4282: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4283: ctype, rname);
1.276 djm 4284: }
4285: }
1.74 markus 4286: error("WARNING: Server requests forwarding for unknown listen_port %d",
4287: listen_port);
1.276 djm 4288: return NULL;
1.73 markus 4289: }
4290:
1.336 millert 4291: Channel *
1.367 djm 4292: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4293: char *ctype, char *rname)
1.336 millert 4294: {
1.367 djm 4295: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4296: struct permission_set *pset = &sc->local_perms;
1.367 djm 4297: u_int i;
1.381 djm 4298: struct permission *perm;
1.336 millert 4299:
1.381 djm 4300: for (i = 0; i < pset->num_permitted_user; i++) {
4301: perm = &pset->permitted_user[i];
4302: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4303: return connect_to(ssh,
1.381 djm 4304: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4305: ctype, rname);
1.336 millert 4306: }
4307: }
4308: error("WARNING: Server requests forwarding for unknown path %.100s",
4309: path);
4310: return NULL;
4311: }
4312:
1.99 markus 4313: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4314: Channel *
1.367 djm 4315: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4316: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4317: {
1.367 djm 4318: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4319: struct permission_set *pset = &sc->local_perms;
1.372 markus 4320: struct channel_connect cctx;
4321: Channel *c;
1.367 djm 4322: u_int i, permit, permit_adm = 1;
1.372 markus 4323: int sock;
1.381 djm 4324: struct permission *perm;
1.99 markus 4325:
1.381 djm 4326: permit = pset->all_permitted;
1.99 markus 4327: if (!permit) {
1.381 djm 4328: for (i = 0; i < pset->num_permitted_user; i++) {
4329: perm = &pset->permitted_user[i];
4330: if (open_match(perm, host, port)) {
1.99 markus 4331: permit = 1;
1.333 markus 4332: break;
4333: }
1.367 djm 4334: }
1.257 dtucker 4335: }
1.99 markus 4336:
1.381 djm 4337: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4338: permit_adm = 0;
1.381 djm 4339: for (i = 0; i < pset->num_permitted_admin; i++) {
4340: perm = &pset->permitted_admin[i];
4341: if (open_match(perm, host, port)) {
1.257 dtucker 4342: permit_adm = 1;
1.333 markus 4343: break;
4344: }
1.367 djm 4345: }
1.99 markus 4346: }
1.257 dtucker 4347:
4348: if (!permit || !permit_adm) {
1.391 florian 4349: logit("Received request from %.100s port %d to connect to "
4350: "host %.100s port %d, but the request was denied.",
4351: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4352: if (reason != NULL)
4353: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4354: return NULL;
1.99 markus 4355: }
1.372 markus 4356:
4357: memset(&cctx, 0, sizeof(cctx));
4358: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4359: &cctx, reason, errmsg);
4360: if (sock == -1) {
4361: channel_connect_ctx_free(&cctx);
4362: return NULL;
4363: }
4364:
4365: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4366: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4367: c->host_port = port;
4368: c->path = xstrdup(host);
4369: c->connect_ctx = cctx;
4370:
4371: return c;
1.336 millert 4372: }
4373:
4374: /* Check if connecting to that path is permitted and connect. */
4375: Channel *
1.367 djm 4376: channel_connect_to_path(struct ssh *ssh, const char *path,
4377: char *ctype, char *rname)
1.336 millert 4378: {
1.367 djm 4379: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4380: struct permission_set *pset = &sc->local_perms;
1.367 djm 4381: u_int i, permit, permit_adm = 1;
1.381 djm 4382: struct permission *perm;
1.336 millert 4383:
1.381 djm 4384: permit = pset->all_permitted;
1.336 millert 4385: if (!permit) {
1.381 djm 4386: for (i = 0; i < pset->num_permitted_user; i++) {
4387: perm = &pset->permitted_user[i];
4388: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4389: permit = 1;
4390: break;
4391: }
1.367 djm 4392: }
1.336 millert 4393: }
4394:
1.381 djm 4395: if (pset->num_permitted_admin > 0) {
1.336 millert 4396: permit_adm = 0;
1.381 djm 4397: for (i = 0; i < pset->num_permitted_admin; i++) {
4398: perm = &pset->permitted_admin[i];
4399: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4400: permit_adm = 1;
4401: break;
4402: }
1.367 djm 4403: }
1.336 millert 4404: }
4405:
4406: if (!permit || !permit_adm) {
4407: logit("Received request to connect to path %.100s, "
4408: "but the request was denied.", path);
4409: return NULL;
4410: }
1.367 djm 4411: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4412: }
4413:
4414: void
1.367 djm 4415: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4416: {
1.367 djm 4417: struct ssh_channels *sc = ssh->chanctxt;
4418: struct winsize ws;
4419: int r;
1.209 avsm 4420: u_int i;
1.204 djm 4421:
1.367 djm 4422: for (i = 0; i < sc->channels_alloc; i++) {
4423: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4424: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4425: continue;
1.393 deraadt 4426: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4427: continue;
1.367 djm 4428: channel_request_start(ssh, i, "window-change", 0);
4429: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4430: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4431: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4432: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4433: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4434: fatal_fr(r, "channel %u; send window-change", i);
1.204 djm 4435: }
1.372 markus 4436: }
4437:
4438: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4439: static Channel *
4440: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4441: {
4442: Channel *c;
4443: int r;
4444:
4445: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4446: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4447: c->host_port = 0;
4448: c->path = NULL;
4449:
4450: /*
4451: * We need to open the channel before we have a FD,
4452: * so that we can get SOCKS header from peer.
4453: */
4454: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4455: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4456: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4457: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 4458: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0)
4459: fatal_fr(r, "channel %i; confirm", c->self);
1.372 markus 4460: return c;
4461: }
4462:
4463: /* Return CONNECTING socket to remote host:port or local socket path */
4464: static int
4465: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4466: {
1.405 markus 4467: struct ssh_channels *sc = ssh->chanctxt;
4468: struct permission_set *pset = &sc->local_perms;
4469: struct permission *perm;
1.372 markus 4470: struct channel_connect cctx;
1.405 markus 4471: u_int i, permit_adm = 1;
1.372 markus 4472: int sock;
1.405 markus 4473:
4474: if (pset->num_permitted_admin > 0) {
4475: permit_adm = 0;
4476: for (i = 0; i < pset->num_permitted_admin; i++) {
4477: perm = &pset->permitted_admin[i];
4478: if (open_match(perm, c->path, c->host_port)) {
4479: permit_adm = 1;
4480: break;
4481: }
4482: }
4483: }
4484: if (!permit_adm) {
4485: debug_f("requested forward not permitted");
4486: return -1;
4487: }
1.372 markus 4488:
4489: memset(&cctx, 0, sizeof(cctx));
4490: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4491: NULL, &cctx, NULL, NULL);
4492: if (sock == -1)
4493: channel_connect_ctx_free(&cctx);
4494: else {
4495: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4496: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4497: c->connect_ctx = cctx;
4498: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4499: }
4500: return sock;
1.99 markus 4501: }
4502:
1.121 markus 4503: /* -- X11 forwarding */
1.1 deraadt 4504:
1.27 markus 4505: /*
4506: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4507: * Returns 0 and a suitable display number for the DISPLAY variable
4508: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4509: */
1.141 stevesk 4510: int
1.367 djm 4511: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4512: int x11_use_localhost, int single_connection,
4513: u_int *display_numberp, int **chanids)
1.1 deraadt 4514: {
1.149 markus 4515: Channel *nc = NULL;
1.31 markus 4516: int display_number, sock;
4517: u_short port;
1.35 markus 4518: struct addrinfo hints, *ai, *aitop;
4519: char strport[NI_MAXSERV];
4520: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4521:
1.224 markus 4522: if (chanids == NULL)
4523: return -1;
4524:
1.33 markus 4525: for (display_number = x11_display_offset;
1.148 deraadt 4526: display_number < MAX_DISPLAYS;
4527: display_number++) {
1.25 markus 4528: port = 6000 + display_number;
1.35 markus 4529: memset(&hints, 0, sizeof(hints));
1.367 djm 4530: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4531: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4532: hints.ai_socktype = SOCK_STREAM;
4533: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4534: if ((gaierr = getaddrinfo(NULL, strport,
4535: &hints, &aitop)) != 0) {
1.271 dtucker 4536: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4537: return -1;
1.25 markus 4538: }
1.35 markus 4539: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4540: if (ai->ai_family != AF_INET &&
4541: ai->ai_family != AF_INET6)
1.35 markus 4542: continue;
1.300 dtucker 4543: sock = socket(ai->ai_family, ai->ai_socktype,
4544: ai->ai_protocol);
1.393 deraadt 4545: if (sock == -1) {
1.35 markus 4546: error("socket: %.100s", strerror(errno));
1.203 markus 4547: freeaddrinfo(aitop);
1.141 stevesk 4548: return -1;
1.35 markus 4549: }
1.376 djm 4550: set_reuseaddr(sock);
1.393 deraadt 4551: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.403 djm 4552: debug2_f("bind port %d: %.100s", port,
4553: strerror(errno));
1.35 markus 4554: close(sock);
1.367 djm 4555: for (n = 0; n < num_socks; n++)
1.35 markus 4556: close(socks[n]);
4557: num_socks = 0;
4558: break;
4559: }
4560: socks[num_socks++] = sock;
4561: if (num_socks == NUM_SOCKS)
4562: break;
1.25 markus 4563: }
1.83 stevesk 4564: freeaddrinfo(aitop);
1.35 markus 4565: if (num_socks > 0)
4566: break;
1.25 markus 4567: }
4568: if (display_number >= MAX_DISPLAYS) {
4569: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4570: return -1;
1.25 markus 4571: }
4572: /* Start listening for connections on the socket. */
1.35 markus 4573: for (n = 0; n < num_socks; n++) {
4574: sock = socks[n];
1.393 deraadt 4575: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 4576: error("listen: %.100s", strerror(errno));
4577: close(sock);
1.141 stevesk 4578: return -1;
1.35 markus 4579: }
1.25 markus 4580: }
1.35 markus 4581:
4582: /* Allocate a channel for each socket. */
1.242 djm 4583: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4584: for (n = 0; n < num_socks; n++) {
4585: sock = socks[n];
1.367 djm 4586: nc = channel_new(ssh, "x11 listener",
1.51 markus 4587: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4588: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4589: 0, "X11 inet listener", 1);
1.167 markus 4590: nc->single_connection = single_connection;
1.224 markus 4591: (*chanids)[n] = nc->self;
1.35 markus 4592: }
1.224 markus 4593: (*chanids)[n] = -1;
1.1 deraadt 4594:
1.141 stevesk 4595: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4596: *display_numberp = display_number;
1.367 djm 4597: return 0;
1.1 deraadt 4598: }
4599:
1.127 itojun 4600: static int
1.77 markus 4601: connect_local_xsocket(u_int dnr)
1.1 deraadt 4602: {
1.25 markus 4603: int sock;
4604: struct sockaddr_un addr;
4605:
1.147 stevesk 4606: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 deraadt 4607: if (sock == -1)
1.147 stevesk 4608: error("socket: %.100s", strerror(errno));
4609: memset(&addr, 0, sizeof(addr));
4610: addr.sun_family = AF_UNIX;
4611: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4612: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4613: return sock;
4614: close(sock);
1.25 markus 4615: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4616: return -1;
1.1 deraadt 4617: }
4618:
1.51 markus 4619: int
1.367 djm 4620: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4621: {
1.248 deraadt 4622: u_int display_number;
1.25 markus 4623: const char *display;
1.51 markus 4624: char buf[1024], *cp;
1.35 markus 4625: struct addrinfo hints, *ai, *aitop;
4626: char strport[NI_MAXSERV];
1.248 deraadt 4627: int gaierr, sock = 0;
1.25 markus 4628:
4629: /* Try to open a socket for the local X server. */
4630: display = getenv("DISPLAY");
4631: if (!display) {
4632: error("DISPLAY not set.");
1.51 markus 4633: return -1;
1.25 markus 4634: }
1.27 markus 4635: /*
4636: * Now we decode the value of the DISPLAY variable and make a
4637: * connection to the real X server.
4638: */
4639:
4640: /*
4641: * Check if it is a unix domain socket. Unix domain displays are in
4642: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4643: */
1.25 markus 4644: if (strncmp(display, "unix:", 5) == 0 ||
4645: display[0] == ':') {
4646: /* Connect to the unix domain socket. */
1.367 djm 4647: if (sscanf(strrchr(display, ':') + 1, "%u",
4648: &display_number) != 1) {
4649: error("Could not parse display number from DISPLAY: "
4650: "%.100s", display);
1.51 markus 4651: return -1;
1.25 markus 4652: }
4653: /* Create a socket. */
4654: sock = connect_local_xsocket(display_number);
4655: if (sock < 0)
1.51 markus 4656: return -1;
1.25 markus 4657:
4658: /* OK, we now have a connection to the display. */
1.51 markus 4659: return sock;
1.25 markus 4660: }
1.27 markus 4661: /*
4662: * Connect to an inet socket. The DISPLAY value is supposedly
4663: * hostname:d[.s], where hostname may also be numeric IP address.
4664: */
1.145 stevesk 4665: strlcpy(buf, display, sizeof(buf));
1.25 markus 4666: cp = strchr(buf, ':');
4667: if (!cp) {
4668: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4669: return -1;
1.25 markus 4670: }
4671: *cp = 0;
1.367 djm 4672: /*
4673: * buf now contains the host name. But first we parse the
4674: * display number.
4675: */
1.248 deraadt 4676: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4677: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4678: display);
1.51 markus 4679: return -1;
1.25 markus 4680: }
1.35 markus 4681:
4682: /* Look up the host address */
4683: memset(&hints, 0, sizeof(hints));
1.367 djm 4684: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4685: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4686: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4687: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4688: error("%.100s: unknown host. (%s)", buf,
4689: ssh_gai_strerror(gaierr));
1.51 markus 4690: return -1;
1.25 markus 4691: }
1.35 markus 4692: for (ai = aitop; ai; ai = ai->ai_next) {
4693: /* Create a socket. */
1.300 dtucker 4694: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 4695: if (sock == -1) {
1.194 markus 4696: debug2("socket: %.100s", strerror(errno));
1.41 markus 4697: continue;
4698: }
4699: /* Connect it to the display. */
1.393 deraadt 4700: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 4701: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4702: 6000 + display_number, strerror(errno));
4703: close(sock);
4704: continue;
4705: }
4706: /* Success */
4707: break;
1.35 markus 4708: }
4709: freeaddrinfo(aitop);
4710: if (!ai) {
1.367 djm 4711: error("connect %.100s port %u: %.100s", buf,
4712: 6000 + display_number, strerror(errno));
1.51 markus 4713: return -1;
1.25 markus 4714: }
1.162 stevesk 4715: set_nodelay(sock);
1.51 markus 4716: return sock;
4717: }
4718:
4719: /*
1.27 markus 4720: * Requests forwarding of X11 connections, generates fake authentication
4721: * data, and enables authentication spoofing.
1.121 markus 4722: * This should be called in the client only.
1.27 markus 4723: */
1.49 markus 4724: void
1.367 djm 4725: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4726: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4727: {
1.367 djm 4728: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4729: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4730: u_int i, value;
1.367 djm 4731: const char *cp;
1.25 markus 4732: char *new_data;
1.367 djm 4733: int r, screen_number;
1.25 markus 4734:
1.367 djm 4735: if (sc->x11_saved_display == NULL)
4736: sc->x11_saved_display = xstrdup(disp);
4737: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4738: error("x11_request_forwarding_with_spoofing: different "
4739: "$DISPLAY already forwarded");
4740: return;
4741: }
4742:
1.266 djm 4743: cp = strchr(disp, ':');
1.25 markus 4744: if (cp)
4745: cp = strchr(cp, '.');
4746: if (cp)
1.245 deraadt 4747: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4748: else
4749: screen_number = 0;
4750:
1.367 djm 4751: if (sc->x11_saved_proto == NULL) {
1.219 djm 4752: /* Save protocol name. */
1.367 djm 4753: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4754:
4755: /* Extract real authentication data. */
1.367 djm 4756: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4757: for (i = 0; i < data_len; i++) {
1.403 djm 4758: if (sscanf(data + 2 * i, "%2x", &value) != 1) {
1.219 djm 4759: fatal("x11_request_forwarding: bad "
4760: "authentication data: %.100s", data);
1.403 djm 4761: }
1.367 djm 4762: sc->x11_saved_data[i] = value;
1.219 djm 4763: }
1.367 djm 4764: sc->x11_saved_data_len = data_len;
1.353 natano 4765:
4766: /* Generate fake data of the same length. */
1.367 djm 4767: sc->x11_fake_data = xmalloc(data_len);
4768: arc4random_buf(sc->x11_fake_data, data_len);
4769: sc->x11_fake_data_len = data_len;
1.25 markus 4770: }
4771:
4772: /* Convert the fake data into hex. */
1.367 djm 4773: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 4774:
4775: /* Send the request packet. */
1.367 djm 4776: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4777: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4778: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4779: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4780: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4781: (r = sshpkt_send(ssh)) != 0 ||
4782: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4783: fatal_fr(r, "send x11-req");
1.321 djm 4784: free(new_data);
1.1 deraadt 4785: }
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