Annotation of src/usr.bin/ssh/channels.c, Revision 1.417
1.417 ! djm 1: /* $OpenBSD: channels.c,v 1.416 2022/04/11 22:52:08 djm Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.336 millert 43: #include <sys/stat.h>
1.234 stevesk 44: #include <sys/ioctl.h>
1.235 stevesk 45: #include <sys/un.h>
1.251 stevesk 46: #include <sys/socket.h>
1.261 stevesk 47: #include <sys/time.h>
1.275 djm 48: #include <sys/queue.h>
1.251 stevesk 49:
50: #include <netinet/in.h>
51: #include <arpa/inet.h>
1.233 stevesk 52:
1.254 stevesk 53: #include <errno.h>
1.298 dtucker 54: #include <fcntl.h>
1.367 djm 55: #include <limits.h>
1.255 stevesk 56: #include <netdb.h>
1.411 djm 57: #include <poll.h>
1.367 djm 58: #include <stdarg.h>
1.341 millert 59: #include <stdint.h>
1.263 stevesk 60: #include <stdio.h>
1.262 stevesk 61: #include <stdlib.h>
1.260 stevesk 62: #include <string.h>
1.233 stevesk 63: #include <termios.h>
1.256 stevesk 64: #include <unistd.h>
1.1 deraadt 65:
1.265 deraadt 66: #include "xmalloc.h"
1.1 deraadt 67: #include "ssh.h"
1.82 markus 68: #include "ssh2.h"
1.354 markus 69: #include "ssherr.h"
1.367 djm 70: #include "sshbuf.h"
1.1 deraadt 71: #include "packet.h"
1.82 markus 72: #include "log.h"
73: #include "misc.h"
1.14 markus 74: #include "channels.h"
75: #include "compat.h"
1.82 markus 76: #include "canohost.h"
1.383 markus 77: #include "sshkey.h"
1.64 markus 78: #include "authfd.h"
1.147 stevesk 79: #include "pathnames.h"
1.381 djm 80: #include "match.h"
1.388 djm 81:
1.411 djm 82: /* XXX remove once we're satisfied there's no lurking bugs */
83: /* #define DEBUG_CHANNEL_POLL 1 */
84:
1.367 djm 85: /* -- agent forwarding */
86: #define NUM_SOCKS 10
1.12 markus 87:
1.367 djm 88: /* -- tcp forwarding */
89: /* special-case port number meaning allow any port */
90: #define FWD_PERMIT_ANY_PORT 0
1.1 deraadt 91:
1.367 djm 92: /* special-case wildcard meaning allow any host */
93: #define FWD_PERMIT_ANY_HOST "*"
1.1 deraadt 94:
1.367 djm 95: /* -- X11 forwarding */
96: /* Maximum number of fake X11 displays to try. */
97: #define MAX_DISPLAYS 1000
1.1 deraadt 98:
1.411 djm 99: /* Per-channel callback for pre/post IO actions */
1.410 djm 100: typedef void chan_fn(struct ssh *, Channel *c);
1.381 djm 101:
1.27 markus 102: /*
103: * Data structure for storing which hosts are permitted for forward requests.
104: * The local sides of any remote forwards are stored in this array to prevent
105: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
106: * network (which might be behind a firewall).
107: */
1.336 millert 108: /* XXX: streamlocal wants a path instead of host:port */
109: /* Overload host_to_connect; we could just make this match Forward */
110: /* XXX - can we use listen_host instead of listen_path? */
1.381 djm 111: struct permission {
1.41 markus 112: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 113: int port_to_connect; /* Connect to 'port'. */
1.333 markus 114: char *listen_host; /* Remote side should listen address. */
1.336 millert 115: char *listen_path; /* Remote side should listen path. */
116: int listen_port; /* Remote side should listen port. */
1.354 markus 117: Channel *downstream; /* Downstream mux*/
1.381 djm 118: };
119:
120: /*
121: * Stores the forwarding permission state for a single direction (local or
122: * remote).
123: */
124: struct permission_set {
125: /*
126: * List of all local permitted host/port pairs to allow for the
127: * user.
128: */
129: u_int num_permitted_user;
130: struct permission *permitted_user;
1.1 deraadt 131:
1.381 djm 132: /*
133: * List of all permitted host/port pairs to allow for the admin.
134: */
135: u_int num_permitted_admin;
136: struct permission *permitted_admin;
137:
138: /*
139: * If this is true, all opens/listens are permitted. This is the
140: * case on the server on which we have to trust the client anyway,
141: * and the user could do anything after logging in.
142: */
143: int all_permitted;
144: };
1.121 markus 145:
1.367 djm 146: /* Master structure for channels state */
147: struct ssh_channels {
148: /*
149: * Pointer to an array containing all allocated channels. The array
150: * is dynamically extended as needed.
151: */
152: Channel **channels;
1.257 dtucker 153:
1.367 djm 154: /*
155: * Size of the channel array. All slots of the array must always be
156: * initialized (at least the type field); unused slots set to NULL
157: */
158: u_int channels_alloc;
1.257 dtucker 159:
1.367 djm 160: /*
1.411 djm 161: * 'channel_pre*' are called just before IO to add any bits
162: * relevant to channels in the c->io_want bitmasks.
1.367 djm 163: *
164: * 'channel_post*': perform any appropriate operations for
1.411 djm 165: * channels which have c->io_ready events pending.
1.367 djm 166: */
167: chan_fn **channel_pre;
168: chan_fn **channel_post;
1.314 dtucker 169:
1.367 djm 170: /* -- tcp forwarding */
1.381 djm 171: struct permission_set local_perms;
172: struct permission_set remote_perms;
1.219 djm 173:
1.367 djm 174: /* -- X11 forwarding */
1.121 markus 175:
1.367 djm 176: /* Saved X11 local (client) display. */
177: char *x11_saved_display;
1.121 markus 178:
1.367 djm 179: /* Saved X11 authentication protocol name. */
180: char *x11_saved_proto;
1.347 djm 181:
1.367 djm 182: /* Saved X11 authentication data. This is the real data. */
183: char *x11_saved_data;
184: u_int x11_saved_data_len;
1.121 markus 185:
1.367 djm 186: /* Deadline after which all X11 connections are refused */
187: u_int x11_refuse_time;
1.121 markus 188:
1.367 djm 189: /*
190: * Fake X11 authentication data. This is what the server will be
191: * sending us; we should replace any occurrences of this by the
192: * real data.
193: */
194: u_char *x11_fake_data;
195: u_int x11_fake_data_len;
1.121 markus 196:
1.367 djm 197: /* AF_UNSPEC or AF_INET or AF_INET6 */
198: int IPv4or6;
199: };
1.1 deraadt 200:
1.121 markus 201: /* helper */
1.367 djm 202: static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
1.354 markus 203: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 204:
1.276 djm 205: /* non-blocking connect helpers */
206: static int connect_next(struct channel_connect *);
207: static void channel_connect_ctx_free(struct channel_connect *);
1.372 markus 208: static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
209: static int rdynamic_connect_finish(struct ssh *, Channel *);
1.276 djm 210:
1.367 djm 211: /* Setup helper */
212: static void channel_handler_init(struct ssh_channels *sc);
213:
1.121 markus 214: /* -- channel core */
1.41 markus 215:
1.367 djm 216: void
217: channel_init_channels(struct ssh *ssh)
218: {
219: struct ssh_channels *sc;
220:
1.387 djm 221: if ((sc = calloc(1, sizeof(*sc))) == NULL)
1.403 djm 222: fatal_f("allocation failed");
1.367 djm 223: sc->channels_alloc = 10;
224: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
225: sc->IPv4or6 = AF_UNSPEC;
226: channel_handler_init(sc);
227:
228: ssh->chanctxt = sc;
229: }
230:
1.41 markus 231: Channel *
1.367 djm 232: channel_by_id(struct ssh *ssh, int id)
1.41 markus 233: {
234: Channel *c;
1.113 markus 235:
1.367 djm 236: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
1.403 djm 237: logit_f("%d: bad id", id);
1.41 markus 238: return NULL;
239: }
1.367 djm 240: c = ssh->chanctxt->channels[id];
1.113 markus 241: if (c == NULL) {
1.403 djm 242: logit_f("%d: bad id: channel free", id);
1.41 markus 243: return NULL;
244: }
245: return c;
1.55 markus 246: }
247:
1.354 markus 248: Channel *
1.368 djm 249: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 250: {
251: Channel *c;
252: u_int i;
253:
1.367 djm 254: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
255: c = ssh->chanctxt->channels[i];
1.368 djm 256: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 257: return c;
258: }
259: return NULL;
260: }
261:
1.27 markus 262: /*
1.229 markus 263: * Returns the channel if it is allowed to receive protocol messages.
264: * Private channels, like listening sockets, may not receive messages.
265: */
266: Channel *
1.367 djm 267: channel_lookup(struct ssh *ssh, int id)
1.229 markus 268: {
269: Channel *c;
270:
1.367 djm 271: if ((c = channel_by_id(ssh, id)) == NULL)
272: return NULL;
1.229 markus 273:
1.237 deraadt 274: switch (c->type) {
1.229 markus 275: case SSH_CHANNEL_X11_OPEN:
276: case SSH_CHANNEL_LARVAL:
277: case SSH_CHANNEL_CONNECTING:
278: case SSH_CHANNEL_DYNAMIC:
1.372 markus 279: case SSH_CHANNEL_RDYNAMIC_OPEN:
280: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 281: case SSH_CHANNEL_OPENING:
282: case SSH_CHANNEL_OPEN:
1.323 dtucker 283: case SSH_CHANNEL_ABANDONED:
1.354 markus 284: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 285: return c;
1.229 markus 286: }
287: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 288: return NULL;
1.229 markus 289: }
290:
291: /*
1.55 markus 292: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 293: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 294: */
1.127 itojun 295: static void
1.367 djm 296: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 297: int extusage, int nonblock, int is_tty)
1.1 deraadt 298: {
1.298 dtucker 299: if (rfd != -1)
300: fcntl(rfd, F_SETFD, FD_CLOEXEC);
301: if (wfd != -1 && wfd != rfd)
302: fcntl(wfd, F_SETFD, FD_CLOEXEC);
303: if (efd != -1 && efd != rfd && efd != wfd)
304: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 305:
1.52 markus 306: c->rfd = rfd;
307: c->wfd = wfd;
308: c->sock = (rfd == wfd) ? rfd : -1;
309: c->efd = efd;
310: c->extended_usage = extusage;
1.71 markus 311:
1.282 dtucker 312: if ((c->isatty = is_tty) != 0)
1.194 markus 313: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 314:
1.71 markus 315: /* enable nonblocking mode */
1.407 djm 316: c->restore_block = 0;
317: if (nonblock == CHANNEL_NONBLOCK_STDIO) {
318: /*
319: * Special handling for stdio file descriptors: do not set
320: * non-blocking mode if they are TTYs. Otherwise prepare to
321: * restore their blocking state on exit to avoid interfering
322: * with other programs that follow.
323: */
324: if (rfd != -1 && !isatty(rfd) && fcntl(rfd, F_GETFL) == 0) {
325: c->restore_block |= CHANNEL_RESTORE_RFD;
326: set_nonblock(rfd);
327: }
328: if (wfd != -1 && !isatty(wfd) && fcntl(wfd, F_GETFL) == 0) {
329: c->restore_block |= CHANNEL_RESTORE_WFD;
330: set_nonblock(wfd);
331: }
332: if (efd != -1 && !isatty(efd) && fcntl(efd, F_GETFL) == 0) {
333: c->restore_block |= CHANNEL_RESTORE_EFD;
334: set_nonblock(efd);
335: }
336: } else if (nonblock) {
1.71 markus 337: if (rfd != -1)
338: set_nonblock(rfd);
339: if (wfd != -1)
340: set_nonblock(wfd);
341: if (efd != -1)
342: set_nonblock(efd);
343: }
1.52 markus 344: }
345:
346: /*
347: * Allocate a new channel object and set its type and socket. This will cause
348: * remote_name to be freed.
349: */
1.113 markus 350: Channel *
1.367 djm 351: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 352: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 353: {
1.367 djm 354: struct ssh_channels *sc = ssh->chanctxt;
355: u_int i, found;
1.52 markus 356: Channel *c;
1.402 djm 357: int r;
1.25 markus 358:
359: /* Try to find a free slot where to put the new channel. */
1.367 djm 360: for (i = 0; i < sc->channels_alloc; i++) {
361: if (sc->channels[i] == NULL) {
1.25 markus 362: /* Found a free slot. */
1.367 djm 363: found = i;
1.25 markus 364: break;
365: }
1.367 djm 366: }
367: if (i >= sc->channels_alloc) {
368: /*
369: * There are no free slots. Take last+1 slot and expand
370: * the array.
371: */
372: found = sc->channels_alloc;
373: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
1.403 djm 374: fatal_f("internal error: channels_alloc %d too big",
375: sc->channels_alloc);
1.367 djm 376: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
377: sc->channels_alloc + 10, sizeof(*sc->channels));
378: sc->channels_alloc += 10;
379: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 380: }
1.113 markus 381: /* Initialize and return new channel. */
1.367 djm 382: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
383: if ((c->input = sshbuf_new()) == NULL ||
384: (c->output = sshbuf_new()) == NULL ||
385: (c->extended = sshbuf_new()) == NULL)
1.403 djm 386: fatal_f("sshbuf_new failed");
1.402 djm 387: if ((r = sshbuf_set_max_size(c->input, CHAN_INPUT_MAX)) != 0)
1.403 djm 388: fatal_fr(r, "sshbuf_set_max_size");
1.159 markus 389: c->ostate = CHAN_OUTPUT_OPEN;
390: c->istate = CHAN_INPUT_OPEN;
1.367 djm 391: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 392: c->self = found;
393: c->type = type;
1.41 markus 394: c->ctype = ctype;
1.51 markus 395: c->local_window = window;
396: c->local_window_max = window;
397: c->local_maxpacket = maxpack;
1.190 markus 398: c->remote_name = xstrdup(remote_name);
1.302 djm 399: c->ctl_chan = -1;
1.299 markus 400: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 401: TAILQ_INIT(&c->status_confirms);
1.25 markus 402: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 403: return c;
1.1 deraadt 404: }
1.52 markus 405:
1.132 markus 406: int
1.407 djm 407: channel_close_fd(struct ssh *ssh, Channel *c, int *fdp)
1.132 markus 408: {
1.407 djm 409: int ret, fd = *fdp;
1.132 markus 410:
1.407 djm 411: if (fd == -1)
412: return 0;
413:
414: if ((*fdp == c->rfd && (c->restore_block & CHANNEL_RESTORE_RFD) != 0) ||
415: (*fdp == c->wfd && (c->restore_block & CHANNEL_RESTORE_WFD) != 0) ||
416: (*fdp == c->efd && (c->restore_block & CHANNEL_RESTORE_EFD) != 0))
417: (void)fcntl(*fdp, F_SETFL, 0); /* restore blocking */
418:
1.411 djm 419: if (*fdp == c->rfd) {
420: c->io_want &= ~SSH_CHAN_IO_RFD;
421: c->io_ready &= ~SSH_CHAN_IO_RFD;
422: c->rfd = -1;
1.415 djm 423: c->pfds[0] = -1;
1.411 djm 424: }
425: if (*fdp == c->wfd) {
426: c->io_want &= ~SSH_CHAN_IO_WFD;
427: c->io_ready &= ~SSH_CHAN_IO_WFD;
428: c->wfd = -1;
1.415 djm 429: c->pfds[1] = -1;
1.411 djm 430: }
431: if (*fdp == c->efd) {
432: c->io_want &= ~SSH_CHAN_IO_EFD;
433: c->io_ready &= ~SSH_CHAN_IO_EFD;
434: c->efd = -1;
1.415 djm 435: c->pfds[2] = -1;
1.411 djm 436: }
437: if (*fdp == c->sock) {
438: c->io_want &= ~SSH_CHAN_IO_SOCK;
439: c->io_ready &= ~SSH_CHAN_IO_SOCK;
440: c->sock = -1;
1.415 djm 441: c->pfds[3] = -1;
1.411 djm 442: }
443:
1.407 djm 444: ret = close(fd);
1.411 djm 445: *fdp = -1; /* probably redundant */
1.132 markus 446: return ret;
447: }
448:
1.52 markus 449: /* Close all channel fd/socket. */
1.127 itojun 450: static void
1.367 djm 451: channel_close_fds(struct ssh *ssh, Channel *c)
452: {
1.379 tb 453: int sock = c->sock, rfd = c->rfd, wfd = c->wfd, efd = c->efd;
454:
1.407 djm 455: channel_close_fd(ssh, c, &c->sock);
1.379 tb 456: if (rfd != sock)
1.407 djm 457: channel_close_fd(ssh, c, &c->rfd);
1.379 tb 458: if (wfd != sock && wfd != rfd)
1.407 djm 459: channel_close_fd(ssh, c, &c->wfd);
1.379 tb 460: if (efd != sock && efd != rfd && efd != wfd)
1.407 djm 461: channel_close_fd(ssh, c, &c->efd);
1.367 djm 462: }
463:
464: static void
1.381 djm 465: fwd_perm_clear(struct permission *perm)
1.52 markus 466: {
1.381 djm 467: free(perm->host_to_connect);
468: free(perm->listen_host);
469: free(perm->listen_path);
1.398 dtucker 470: memset(perm, 0, sizeof(*perm));
1.367 djm 471: }
472:
1.381 djm 473: /* Returns an printable name for the specified forwarding permission list */
474: static const char *
475: fwd_ident(int who, int where)
476: {
477: if (who == FORWARD_ADM) {
478: if (where == FORWARD_LOCAL)
479: return "admin local";
480: else if (where == FORWARD_REMOTE)
481: return "admin remote";
482: } else if (who == FORWARD_USER) {
483: if (where == FORWARD_LOCAL)
484: return "user local";
485: else if (where == FORWARD_REMOTE)
486: return "user remote";
487: }
488: fatal("Unknown forward permission list %d/%d", who, where);
489: }
490:
491: /* Returns the forwarding permission list for the specified direction */
492: static struct permission_set *
493: permission_set_get(struct ssh *ssh, int where)
494: {
495: struct ssh_channels *sc = ssh->chanctxt;
1.367 djm 496:
1.381 djm 497: switch (where) {
498: case FORWARD_LOCAL:
499: return &sc->local_perms;
500: break;
501: case FORWARD_REMOTE:
502: return &sc->remote_perms;
503: break;
504: default:
1.403 djm 505: fatal_f("invalid forwarding direction %d", where);
1.381 djm 506: }
507: }
508:
1.392 dtucker 509: /* Returns pointers to the specified forwarding list and its element count */
1.381 djm 510: static void
511: permission_set_get_array(struct ssh *ssh, int who, int where,
512: struct permission ***permpp, u_int **npermpp)
513: {
514: struct permission_set *pset = permission_set_get(ssh, where);
515:
516: switch (who) {
517: case FORWARD_USER:
518: *permpp = &pset->permitted_user;
519: *npermpp = &pset->num_permitted_user;
520: break;
521: case FORWARD_ADM:
522: *permpp = &pset->permitted_admin;
523: *npermpp = &pset->num_permitted_admin;
524: break;
525: default:
1.403 djm 526: fatal_f("invalid forwarding client %d", who);
1.381 djm 527: }
528: }
529:
1.409 jsg 530: /* Adds an entry to the specified forwarding list */
1.367 djm 531: static int
1.381 djm 532: permission_set_add(struct ssh *ssh, int who, int where,
1.367 djm 533: const char *host_to_connect, int port_to_connect,
534: const char *listen_host, const char *listen_path, int listen_port,
535: Channel *downstream)
536: {
1.381 djm 537: struct permission **permp;
538: u_int n, *npermp;
1.367 djm 539:
1.381 djm 540: permission_set_get_array(ssh, who, where, &permp, &npermp);
1.367 djm 541:
1.381 djm 542: if (*npermp >= INT_MAX)
1.403 djm 543: fatal_f("%s overflow", fwd_ident(who, where));
1.367 djm 544:
1.381 djm 545: *permp = xrecallocarray(*permp, *npermp, *npermp + 1, sizeof(**permp));
546: n = (*npermp)++;
1.367 djm 547: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
1.381 djm 548: (*permp)[n].host_to_connect = MAYBE_DUP(host_to_connect);
549: (*permp)[n].port_to_connect = port_to_connect;
550: (*permp)[n].listen_host = MAYBE_DUP(listen_host);
551: (*permp)[n].listen_path = MAYBE_DUP(listen_path);
552: (*permp)[n].listen_port = listen_port;
553: (*permp)[n].downstream = downstream;
1.367 djm 554: #undef MAYBE_DUP
555: return (int)n;
556: }
557:
558: static void
559: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
560: {
561: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 562: struct permission_set *pset = &sc->local_perms;
563: struct permission *perm;
1.367 djm 564: int r;
565: u_int i;
566:
1.381 djm 567: for (i = 0; i < pset->num_permitted_user; i++) {
568: perm = &pset->permitted_user[i];
569: if (perm->downstream != c)
1.367 djm 570: continue;
571:
572: /* cancel on the server, since mux client is gone */
573: debug("channel %d: cleanup remote forward for %s:%u",
1.381 djm 574: c->self, perm->listen_host, perm->listen_port);
1.367 djm 575: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
576: (r = sshpkt_put_cstring(ssh,
577: "cancel-tcpip-forward")) != 0 ||
578: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
579: (r = sshpkt_put_cstring(ssh,
1.381 djm 580: channel_rfwd_bind_host(perm->listen_host))) != 0 ||
581: (r = sshpkt_put_u32(ssh, perm->listen_port)) != 0 ||
1.367 djm 582: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 583: fatal_fr(r, "channel %i", c->self);
1.367 djm 584: }
1.381 djm 585: fwd_perm_clear(perm); /* unregister */
1.367 djm 586: }
1.121 markus 587: }
588:
589: /* Free the channel and close its fd/socket. */
590: void
1.367 djm 591: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 592: {
1.367 djm 593: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 594: char *s;
1.209 avsm 595: u_int i, n;
1.354 markus 596: Channel *other;
1.275 djm 597: struct channel_confirm *cc;
1.121 markus 598:
1.367 djm 599: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
600: if ((other = sc->channels[i]) == NULL)
601: continue;
602: n++;
603: /* detach from mux client and prepare for closing */
604: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
605: other->type == SSH_CHANNEL_MUX_PROXY &&
606: other->mux_ctx == c) {
607: other->mux_ctx = NULL;
608: other->type = SSH_CHANNEL_OPEN;
609: other->istate = CHAN_INPUT_CLOSED;
610: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 611: }
612: }
1.209 avsm 613: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 614: c->remote_name ? c->remote_name : "???", n);
615:
1.408 mbuhl 616: if (c->type == SSH_CHANNEL_MUX_CLIENT) {
1.367 djm 617: mux_remove_remote_forwardings(ssh, c);
1.408 mbuhl 618: free(c->mux_ctx);
619: c->mux_ctx = NULL;
620: } else if (c->type == SSH_CHANNEL_MUX_LISTENER) {
1.401 djm 621: free(c->mux_ctx);
622: c->mux_ctx = NULL;
623: }
1.354 markus 624:
1.384 markus 625: if (log_level_get() >= SYSLOG_LEVEL_DEBUG3) {
626: s = channel_open_message(ssh);
627: debug3("channel %d: status: %s", c->self, s);
628: free(s);
629: }
1.121 markus 630:
1.367 djm 631: channel_close_fds(ssh, c);
632: sshbuf_free(c->input);
633: sshbuf_free(c->output);
634: sshbuf_free(c->extended);
635: c->input = c->output = c->extended = NULL;
1.321 djm 636: free(c->remote_name);
637: c->remote_name = NULL;
638: free(c->path);
639: c->path = NULL;
640: free(c->listening_addr);
641: c->listening_addr = NULL;
1.275 djm 642: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
643: if (cc->abandon_cb != NULL)
1.367 djm 644: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 645: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 646: freezero(cc, sizeof(*cc));
1.275 djm 647: }
1.280 djm 648: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 649: c->filter_cleanup(ssh, c->self, c->filter_ctx);
650: sc->channels[c->self] = NULL;
1.396 jsg 651: freezero(c, sizeof(*c));
1.121 markus 652: }
653:
654: void
1.367 djm 655: channel_free_all(struct ssh *ssh)
1.121 markus 656: {
1.209 avsm 657: u_int i;
1.390 dtucker 658: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 659:
1.390 dtucker 660: for (i = 0; i < sc->channels_alloc; i++)
661: if (sc->channels[i] != NULL)
662: channel_free(ssh, sc->channels[i]);
663:
664: free(sc->channels);
665: sc->channels = NULL;
666: sc->channels_alloc = 0;
667:
668: free(sc->x11_saved_display);
669: sc->x11_saved_display = NULL;
670:
671: free(sc->x11_saved_proto);
672: sc->x11_saved_proto = NULL;
673:
674: free(sc->x11_saved_data);
675: sc->x11_saved_data = NULL;
676: sc->x11_saved_data_len = 0;
677:
678: free(sc->x11_fake_data);
679: sc->x11_fake_data = NULL;
680: sc->x11_fake_data_len = 0;
1.131 markus 681: }
682:
1.121 markus 683: /*
684: * Closes the sockets/fds of all channels. This is used to close extra file
685: * descriptors after a fork.
686: */
687: void
1.367 djm 688: channel_close_all(struct ssh *ssh)
1.121 markus 689: {
1.209 avsm 690: u_int i;
1.121 markus 691:
1.367 djm 692: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
693: if (ssh->chanctxt->channels[i] != NULL)
694: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 695: }
696:
697: /*
1.131 markus 698: * Stop listening to channels.
699: */
700: void
1.367 djm 701: channel_stop_listening(struct ssh *ssh)
1.131 markus 702: {
1.209 avsm 703: u_int i;
1.131 markus 704: Channel *c;
705:
1.367 djm 706: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
707: c = ssh->chanctxt->channels[i];
1.131 markus 708: if (c != NULL) {
709: switch (c->type) {
710: case SSH_CHANNEL_AUTH_SOCKET:
711: case SSH_CHANNEL_PORT_LISTENER:
712: case SSH_CHANNEL_RPORT_LISTENER:
713: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 714: case SSH_CHANNEL_UNIX_LISTENER:
715: case SSH_CHANNEL_RUNIX_LISTENER:
1.407 djm 716: channel_close_fd(ssh, c, &c->sock);
1.367 djm 717: channel_free(ssh, c);
1.131 markus 718: break;
719: }
720: }
721: }
722: }
723:
724: /*
1.121 markus 725: * Returns true if no channel has too much buffered data, and false if one or
726: * more channel is overfull.
727: */
728: int
1.367 djm 729: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 730: {
731: u_int i;
1.367 djm 732: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 733: Channel *c;
734:
1.367 djm 735: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
736: c = ssh->chanctxt->channels[i];
737: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
738: continue;
739: if (sshbuf_len(c->output) > maxsize) {
740: debug2("channel %d: big output buffer %zu > %u",
741: c->self, sshbuf_len(c->output), maxsize);
742: return 0;
1.121 markus 743: }
744: }
745: return 1;
746: }
747:
748: /* Returns true if any channel is still open. */
749: int
1.367 djm 750: channel_still_open(struct ssh *ssh)
1.121 markus 751: {
1.209 avsm 752: u_int i;
1.121 markus 753: Channel *c;
754:
1.367 djm 755: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
756: c = ssh->chanctxt->channels[i];
1.121 markus 757: if (c == NULL)
758: continue;
759: switch (c->type) {
760: case SSH_CHANNEL_X11_LISTENER:
761: case SSH_CHANNEL_PORT_LISTENER:
762: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 763: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 764: case SSH_CHANNEL_CLOSED:
765: case SSH_CHANNEL_AUTH_SOCKET:
766: case SSH_CHANNEL_DYNAMIC:
1.372 markus 767: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 768: case SSH_CHANNEL_CONNECTING:
769: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 770: case SSH_CHANNEL_ABANDONED:
1.336 millert 771: case SSH_CHANNEL_UNIX_LISTENER:
772: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 773: continue;
774: case SSH_CHANNEL_LARVAL:
775: continue;
776: case SSH_CHANNEL_OPENING:
777: case SSH_CHANNEL_OPEN:
1.372 markus 778: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 779: case SSH_CHANNEL_X11_OPEN:
1.302 djm 780: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 781: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 782: return 1;
783: default:
1.403 djm 784: fatal_f("bad channel type %d", c->type);
1.121 markus 785: /* NOTREACHED */
786: }
787: }
788: return 0;
789: }
790:
791: /* Returns the id of an open channel suitable for keepaliving */
792: int
1.367 djm 793: channel_find_open(struct ssh *ssh)
1.121 markus 794: {
1.209 avsm 795: u_int i;
1.121 markus 796: Channel *c;
797:
1.367 djm 798: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
799: c = ssh->chanctxt->channels[i];
1.368 djm 800: if (c == NULL || !c->have_remote_id)
1.121 markus 801: continue;
802: switch (c->type) {
803: case SSH_CHANNEL_CLOSED:
804: case SSH_CHANNEL_DYNAMIC:
1.372 markus 805: case SSH_CHANNEL_RDYNAMIC_OPEN:
806: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 807: case SSH_CHANNEL_X11_LISTENER:
808: case SSH_CHANNEL_PORT_LISTENER:
809: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 810: case SSH_CHANNEL_MUX_LISTENER:
811: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 812: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 813: case SSH_CHANNEL_OPENING:
814: case SSH_CHANNEL_CONNECTING:
815: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 816: case SSH_CHANNEL_ABANDONED:
1.336 millert 817: case SSH_CHANNEL_UNIX_LISTENER:
818: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 819: continue;
820: case SSH_CHANNEL_LARVAL:
821: case SSH_CHANNEL_AUTH_SOCKET:
822: case SSH_CHANNEL_OPEN:
823: case SSH_CHANNEL_X11_OPEN:
824: return i;
825: default:
1.403 djm 826: fatal_f("bad channel type %d", c->type);
1.121 markus 827: /* NOTREACHED */
828: }
829: }
830: return -1;
831: }
832:
1.385 djm 833: /* Returns the state of the channel's extended usage flag */
834: const char *
835: channel_format_extended_usage(const Channel *c)
836: {
837: if (c->efd == -1)
838: return "closed";
839:
840: switch (c->extended_usage) {
841: case CHAN_EXTENDED_WRITE:
842: return "write";
843: case CHAN_EXTENDED_READ:
844: return "read";
845: case CHAN_EXTENDED_IGNORE:
846: return "ignore";
847: default:
848: return "UNKNOWN";
849: }
850: }
851:
1.386 djm 852: static char *
853: channel_format_status(const Channel *c)
854: {
855: char *ret = NULL;
856:
857: xasprintf(&ret, "t%d %s%u i%u/%zu o%u/%zu e[%s]/%zu "
1.411 djm 858: "fd %d/%d/%d sock %d cc %d io 0x%02x/0x%02x",
1.386 djm 859: c->type,
860: c->have_remote_id ? "r" : "nr", c->remote_id,
861: c->istate, sshbuf_len(c->input),
862: c->ostate, sshbuf_len(c->output),
863: channel_format_extended_usage(c), sshbuf_len(c->extended),
1.411 djm 864: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan,
865: c->io_want, c->io_ready);
1.386 djm 866: return ret;
867: }
868:
1.121 markus 869: /*
870: * Returns a message describing the currently open forwarded connections,
871: * suitable for sending to the client. The message contains crlf pairs for
872: * newlines.
873: */
874: char *
1.367 djm 875: channel_open_message(struct ssh *ssh)
1.121 markus 876: {
1.367 djm 877: struct sshbuf *buf;
1.121 markus 878: Channel *c;
1.209 avsm 879: u_int i;
1.367 djm 880: int r;
1.386 djm 881: char *cp, *ret;
1.121 markus 882:
1.367 djm 883: if ((buf = sshbuf_new()) == NULL)
1.403 djm 884: fatal_f("sshbuf_new");
1.367 djm 885: if ((r = sshbuf_putf(buf,
886: "The following connections are open:\r\n")) != 0)
1.403 djm 887: fatal_fr(r, "sshbuf_putf");
1.367 djm 888: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
889: c = ssh->chanctxt->channels[i];
1.121 markus 890: if (c == NULL)
891: continue;
892: switch (c->type) {
893: case SSH_CHANNEL_X11_LISTENER:
894: case SSH_CHANNEL_PORT_LISTENER:
895: case SSH_CHANNEL_RPORT_LISTENER:
896: case SSH_CHANNEL_CLOSED:
897: case SSH_CHANNEL_AUTH_SOCKET:
898: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 899: case SSH_CHANNEL_ABANDONED:
1.302 djm 900: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 901: case SSH_CHANNEL_UNIX_LISTENER:
902: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 903: continue;
904: case SSH_CHANNEL_LARVAL:
905: case SSH_CHANNEL_OPENING:
906: case SSH_CHANNEL_CONNECTING:
907: case SSH_CHANNEL_DYNAMIC:
1.372 markus 908: case SSH_CHANNEL_RDYNAMIC_OPEN:
909: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 910: case SSH_CHANNEL_OPEN:
911: case SSH_CHANNEL_X11_OPEN:
1.354 markus 912: case SSH_CHANNEL_MUX_PROXY:
913: case SSH_CHANNEL_MUX_CLIENT:
1.386 djm 914: cp = channel_format_status(c);
915: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
916: c->self, c->remote_name, cp)) != 0) {
917: free(cp);
1.403 djm 918: fatal_fr(r, "sshbuf_putf");
1.386 djm 919: }
920: free(cp);
1.121 markus 921: continue;
922: default:
1.403 djm 923: fatal_f("bad channel type %d", c->type);
1.121 markus 924: /* NOTREACHED */
925: }
926: }
1.367 djm 927: if ((ret = sshbuf_dup_string(buf)) == NULL)
1.403 djm 928: fatal_f("sshbuf_dup_string");
1.367 djm 929: sshbuf_free(buf);
930: return ret;
931: }
932:
933: static void
934: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
935: {
936: int r;
937:
938: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
939: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
940: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
941: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
942: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
1.403 djm 943: fatal_r(r, "%s: channel %i: open", where, c->self);
1.367 djm 944: }
1.121 markus 945: }
946:
947: void
1.367 djm 948: channel_send_open(struct ssh *ssh, int id)
1.121 markus 949: {
1.367 djm 950: Channel *c = channel_lookup(ssh, id);
951: int r;
1.180 deraadt 952:
1.121 markus 953: if (c == NULL) {
1.188 itojun 954: logit("channel_send_open: %d: bad id", id);
1.121 markus 955: return;
956: }
1.184 markus 957: debug2("channel %d: send open", id);
1.367 djm 958: open_preamble(ssh, __func__, c, c->ctype);
959: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 960: fatal_fr(r, "channel %i", c->self);
1.121 markus 961: }
962:
963: void
1.367 djm 964: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 965: {
1.367 djm 966: Channel *c = channel_lookup(ssh, id);
967: int r;
1.180 deraadt 968:
1.121 markus 969: if (c == NULL) {
1.403 djm 970: logit_f("%d: unknown channel id", id);
1.121 markus 971: return;
972: }
1.368 djm 973: if (!c->have_remote_id)
1.403 djm 974: fatal_f("channel %d: no remote id", c->self);
1.368 djm 975:
1.204 djm 976: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 977: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
978: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
979: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
980: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
1.403 djm 981: fatal_fr(r, "channel %i", c->self);
1.367 djm 982: }
1.121 markus 983: }
1.241 deraadt 984:
1.121 markus 985: void
1.367 djm 986: channel_register_status_confirm(struct ssh *ssh, int id,
987: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 988: {
989: struct channel_confirm *cc;
990: Channel *c;
991:
1.367 djm 992: if ((c = channel_lookup(ssh, id)) == NULL)
1.403 djm 993: fatal_f("%d: bad id", id);
1.275 djm 994:
1.327 djm 995: cc = xcalloc(1, sizeof(*cc));
1.275 djm 996: cc->cb = cb;
997: cc->abandon_cb = abandon_cb;
998: cc->ctx = ctx;
999: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
1000: }
1001:
1002: void
1.367 djm 1003: channel_register_open_confirm(struct ssh *ssh, int id,
1004: channel_open_fn *fn, void *ctx)
1.121 markus 1005: {
1.367 djm 1006: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1007:
1.121 markus 1008: if (c == NULL) {
1.403 djm 1009: logit_f("%d: bad id", id);
1.121 markus 1010: return;
1011: }
1.275 djm 1012: c->open_confirm = fn;
1013: c->open_confirm_ctx = ctx;
1.121 markus 1014: }
1.241 deraadt 1015:
1.121 markus 1016: void
1.367 djm 1017: channel_register_cleanup(struct ssh *ssh, int id,
1018: channel_callback_fn *fn, int do_close)
1.121 markus 1019: {
1.367 djm 1020: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1021:
1.121 markus 1022: if (c == NULL) {
1.403 djm 1023: logit_f("%d: bad id", id);
1.121 markus 1024: return;
1025: }
1.131 markus 1026: c->detach_user = fn;
1.225 djm 1027: c->detach_close = do_close;
1.121 markus 1028: }
1.241 deraadt 1029:
1.121 markus 1030: void
1.367 djm 1031: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 1032: {
1.367 djm 1033: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1034:
1.121 markus 1035: if (c == NULL) {
1.403 djm 1036: logit_f("%d: bad id", id);
1.121 markus 1037: return;
1.52 markus 1038: }
1.131 markus 1039: c->detach_user = NULL;
1.225 djm 1040: c->detach_close = 0;
1.121 markus 1041: }
1.241 deraadt 1042:
1.121 markus 1043: void
1.367 djm 1044: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1045: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1046: {
1.367 djm 1047: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1048:
1.121 markus 1049: if (c == NULL) {
1.403 djm 1050: logit_f("%d: bad id", id);
1.121 markus 1051: return;
1.52 markus 1052: }
1.231 reyk 1053: c->input_filter = ifn;
1054: c->output_filter = ofn;
1.279 djm 1055: c->filter_ctx = ctx;
1.280 djm 1056: c->filter_cleanup = cfn;
1.52 markus 1057: }
1058:
1.49 markus 1059: void
1.367 djm 1060: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1061: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1062: {
1.367 djm 1063: Channel *c = channel_lookup(ssh, id);
1064: int r;
1.180 deraadt 1065:
1.121 markus 1066: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1067: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1068: if (!c->have_remote_id)
1.403 djm 1069: fatal_f("channel %d: no remote id", c->self);
1.368 djm 1070:
1.367 djm 1071: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1072: c->type = SSH_CHANNEL_OPEN;
1.168 markus 1073: c->local_window = c->local_window_max = window_max;
1.367 djm 1074:
1075: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1076: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1077: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1078: (r = sshpkt_send(ssh)) != 0)
1.403 djm 1079: fatal_fr(r, "channel %i", c->self);
1.1 deraadt 1080: }
1081:
1.127 itojun 1082: static void
1.410 djm 1083: channel_pre_listener(struct ssh *ssh, Channel *c)
1.41 markus 1084: {
1.410 djm 1085: c->io_want = SSH_CHAN_IO_SOCK_R;
1.41 markus 1086: }
1087:
1.127 itojun 1088: static void
1.410 djm 1089: channel_pre_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1090: {
1091: debug3("channel %d: waiting for connection", c->self);
1.410 djm 1092: c->io_want = SSH_CHAN_IO_SOCK_W;
1.75 markus 1093: }
1094:
1.127 itojun 1095: static void
1.410 djm 1096: channel_pre_open(struct ssh *ssh, Channel *c)
1.41 markus 1097: {
1.410 djm 1098: c->io_want = 0;
1.44 markus 1099: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1100: c->remote_window > 0 &&
1.367 djm 1101: sshbuf_len(c->input) < c->remote_window &&
1102: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1103: c->io_want |= SSH_CHAN_IO_RFD;
1.44 markus 1104: if (c->ostate == CHAN_OUTPUT_OPEN ||
1105: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1106: if (sshbuf_len(c->output) > 0) {
1.410 djm 1107: c->io_want |= SSH_CHAN_IO_WFD;
1.44 markus 1108: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1109: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1110: debug2("channel %d: "
1111: "obuf_empty delayed efd %d/(%zu)", c->self,
1112: c->efd, sshbuf_len(c->extended));
1.172 markus 1113: else
1.367 djm 1114: chan_obuf_empty(ssh, c);
1.44 markus 1115: }
1116: }
1117: /** XXX check close conditions, too */
1.358 djm 1118: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1119: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1120: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1121: sshbuf_len(c->extended) > 0)
1.410 djm 1122: c->io_want |= SSH_CHAN_IO_EFD_W;
1.306 djm 1123: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1124: (c->extended_usage == CHAN_EXTENDED_READ ||
1125: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1126: sshbuf_len(c->extended) < c->remote_window)
1.410 djm 1127: c->io_want |= SSH_CHAN_IO_EFD_R;
1.44 markus 1128: }
1.204 djm 1129: /* XXX: What about efd? races? */
1.44 markus 1130: }
1131:
1.41 markus 1132: /*
1133: * This is a special state for X11 authentication spoofing. An opened X11
1134: * connection (when authentication spoofing is being done) remains in this
1135: * state until the first packet has been completely read. The authentication
1136: * data in that packet is then substituted by the real data if it matches the
1137: * fake data, and the channel is put into normal mode.
1.51 markus 1138: * XXX All this happens at the client side.
1.121 markus 1139: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1140: */
1.127 itojun 1141: static int
1.367 djm 1142: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1143: {
1.367 djm 1144: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1145: u_char *ucp;
1146: u_int proto_len, data_len;
1.25 markus 1147:
1.347 djm 1148: /* Is this being called after the refusal deadline? */
1.367 djm 1149: if (sc->x11_refuse_time != 0 &&
1150: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1151: verbose("Rejected X11 connection after ForwardX11Timeout "
1152: "expired");
1153: return -1;
1154: }
1155:
1.41 markus 1156: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1157: if (sshbuf_len(b) < 12)
1.41 markus 1158: return 0;
1159:
1160: /* Parse the lengths of variable-length fields. */
1.367 djm 1161: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1162: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1163: proto_len = 256 * ucp[6] + ucp[7];
1164: data_len = 256 * ucp[8] + ucp[9];
1165: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1166: proto_len = ucp[6] + 256 * ucp[7];
1167: data_len = ucp[8] + 256 * ucp[9];
1168: } else {
1.194 markus 1169: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1170: ucp[0]);
1.41 markus 1171: return -1;
1172: }
1173:
1174: /* Check if the whole packet is in buffer. */
1.367 djm 1175: if (sshbuf_len(b) <
1.41 markus 1176: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1177: return 0;
1178:
1179: /* Check if authentication protocol matches. */
1.367 djm 1180: if (proto_len != strlen(sc->x11_saved_proto) ||
1181: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1182: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1183: return -1;
1184: }
1185: /* Check if authentication data matches our fake data. */
1.367 djm 1186: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1187: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1188: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1189: debug2("X11 auth data does not match fake data.");
1.41 markus 1190: return -1;
1191: }
1192: /* Check fake data length */
1.367 djm 1193: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1194: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1195: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1196: return -1;
1197: }
1198: /*
1199: * Received authentication protocol and data match
1200: * our fake data. Substitute the fake data with real
1201: * data.
1202: */
1203: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1204: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1205: return 1;
1206: }
1207:
1.127 itojun 1208: static void
1.410 djm 1209: channel_pre_x11_open(struct ssh *ssh, Channel *c)
1.41 markus 1210: {
1.367 djm 1211: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1212:
1213: /* c->force_drain = 1; */
1214:
1.41 markus 1215: if (ret == 1) {
1216: c->type = SSH_CHANNEL_OPEN;
1.410 djm 1217: channel_pre_open(ssh, c);
1.41 markus 1218: } else if (ret == -1) {
1.188 itojun 1219: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1220: debug2("X11 rejected %d i%d/o%d",
1221: c->self, c->istate, c->ostate);
1222: chan_read_failed(ssh, c);
1223: sshbuf_reset(c->input);
1224: chan_ibuf_empty(ssh, c);
1225: sshbuf_reset(c->output);
1226: chan_write_failed(ssh, c);
1.194 markus 1227: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1228: }
1229: }
1.25 markus 1230:
1.302 djm 1231: static void
1.410 djm 1232: channel_pre_mux_client(struct ssh *ssh, Channel *c)
1.302 djm 1233: {
1.410 djm 1234: c->io_want = 0;
1.304 djm 1235: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1236: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1237: c->io_want |= SSH_CHAN_IO_RFD;
1.302 djm 1238: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1239: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1240: sshbuf_reset(c->input);
1241: chan_ibuf_empty(ssh, c);
1.302 djm 1242: /* Start output drain. XXX just kill chan? */
1.367 djm 1243: chan_rcvd_oclose(ssh, c);
1.302 djm 1244: }
1245: if (c->ostate == CHAN_OUTPUT_OPEN ||
1246: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1247: if (sshbuf_len(c->output) > 0)
1.410 djm 1248: c->io_want |= SSH_CHAN_IO_WFD;
1.302 djm 1249: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1250: chan_obuf_empty(ssh, c);
1.302 djm 1251: }
1252: }
1253:
1.104 markus 1254: /* try to decode a socks4 header */
1.127 itojun 1255: static int
1.372 markus 1256: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1257: {
1.367 djm 1258: const u_char *p;
1259: char *host;
1.292 djm 1260: u_int len, have, i, found, need;
1.148 deraadt 1261: char username[256];
1.103 markus 1262: struct {
1263: u_int8_t version;
1264: u_int8_t command;
1265: u_int16_t dest_port;
1.104 markus 1266: struct in_addr dest_addr;
1.103 markus 1267: } s4_req, s4_rsp;
1.367 djm 1268: int r;
1.103 markus 1269:
1.104 markus 1270: debug2("channel %d: decode socks4", c->self);
1.109 markus 1271:
1.372 markus 1272: have = sshbuf_len(input);
1.109 markus 1273: len = sizeof(s4_req);
1274: if (have < len)
1275: return 0;
1.372 markus 1276: p = sshbuf_ptr(input);
1.292 djm 1277:
1278: need = 1;
1279: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1280: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1281: debug2("channel %d: socks4a request", c->self);
1282: /* ... and needs an extra string (the hostname) */
1283: need = 2;
1284: }
1285: /* Check for terminating NUL on the string(s) */
1.109 markus 1286: for (found = 0, i = len; i < have; i++) {
1287: if (p[i] == '\0') {
1.292 djm 1288: found++;
1289: if (found == need)
1290: break;
1.109 markus 1291: }
1292: if (i > 1024) {
1293: /* the peer is probably sending garbage */
1294: debug("channel %d: decode socks4: too long",
1295: c->self);
1296: return -1;
1297: }
1298: }
1.292 djm 1299: if (found < need)
1.109 markus 1300: return 0;
1.372 markus 1301: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1302: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1303: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1304: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.403 djm 1305: debug_r(r, "channels %d: decode socks4", c->self);
1.367 djm 1306: return -1;
1307: }
1.372 markus 1308: have = sshbuf_len(input);
1309: p = sshbuf_ptr(input);
1.364 djm 1310: if (memchr(p, '\0', have) == NULL) {
1.403 djm 1311: error("channel %d: decode socks4: unterminated user", c->self);
1.364 djm 1312: return -1;
1313: }
1.103 markus 1314: len = strlen(p);
1.106 markus 1315: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1316: len++; /* trailing '\0' */
1.103 markus 1317: strlcpy(username, p, sizeof(username));
1.403 djm 1318: if ((r = sshbuf_consume(input, len)) != 0)
1319: fatal_fr(r, "channel %d: consume", c->self);
1.321 djm 1320: free(c->path);
1321: c->path = NULL;
1.292 djm 1322: if (need == 1) { /* SOCKS4: one string */
1323: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1324: c->path = xstrdup(host);
1.292 djm 1325: } else { /* SOCKS4A: two strings */
1.372 markus 1326: have = sshbuf_len(input);
1327: p = sshbuf_ptr(input);
1.364 djm 1328: if (memchr(p, '\0', have) == NULL) {
1329: error("channel %d: decode socks4a: host not nul "
1330: "terminated", c->self);
1331: return -1;
1332: }
1.292 djm 1333: len = strlen(p);
1334: debug2("channel %d: decode socks4a: host %s/%d",
1335: c->self, p, len);
1336: len++; /* trailing '\0' */
1.293 djm 1337: if (len > NI_MAXHOST) {
1.292 djm 1338: error("channel %d: hostname \"%.100s\" too long",
1339: c->self, p);
1340: return -1;
1341: }
1.293 djm 1342: c->path = xstrdup(p);
1.403 djm 1343: if ((r = sshbuf_consume(input, len)) != 0)
1344: fatal_fr(r, "channel %d: consume", c->self);
1.292 djm 1345: }
1.103 markus 1346: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1347:
1.194 markus 1348: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1349: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1350:
1.104 markus 1351: if (s4_req.command != 1) {
1.292 djm 1352: debug("channel %d: cannot handle: %s cn %d",
1353: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1354: return -1;
1.103 markus 1355: }
1.104 markus 1356: s4_rsp.version = 0; /* vn: 0 for reply */
1357: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1358: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1359: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.403 djm 1360: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0)
1361: fatal_fr(r, "channel %d: append reply", c->self);
1.104 markus 1362: return 1;
1363: }
1364:
1.193 markus 1365: /* try to decode a socks5 header */
1366: #define SSH_SOCKS5_AUTHDONE 0x1000
1367: #define SSH_SOCKS5_NOAUTH 0x00
1368: #define SSH_SOCKS5_IPV4 0x01
1369: #define SSH_SOCKS5_DOMAIN 0x03
1370: #define SSH_SOCKS5_IPV6 0x04
1371: #define SSH_SOCKS5_CONNECT 0x01
1372: #define SSH_SOCKS5_SUCCESS 0x00
1373:
1374: static int
1.372 markus 1375: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1376: {
1.367 djm 1377: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1378: struct {
1379: u_int8_t version;
1380: u_int8_t command;
1381: u_int8_t reserved;
1382: u_int8_t atyp;
1383: } s5_req, s5_rsp;
1384: u_int16_t dest_port;
1.324 djm 1385: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1386: const u_char *p;
1.252 djm 1387: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1388: int r;
1.193 markus 1389:
1390: debug2("channel %d: decode socks5", c->self);
1.372 markus 1391: p = sshbuf_ptr(input);
1.193 markus 1392: if (p[0] != 0x05)
1393: return -1;
1.372 markus 1394: have = sshbuf_len(input);
1.193 markus 1395: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1396: /* format: ver | nmethods | methods */
1.198 djm 1397: if (have < 2)
1.193 markus 1398: return 0;
1399: nmethods = p[1];
1400: if (have < nmethods + 2)
1401: return 0;
1402: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1403: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1404: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1405: found = 1;
1406: break;
1407: }
1408: }
1409: if (!found) {
1410: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1411: c->self);
1412: return -1;
1413: }
1.403 djm 1414: if ((r = sshbuf_consume(input, nmethods + 2)) != 0)
1415: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1416: /* version, method */
1.372 markus 1417: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1.403 djm 1418: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0)
1419: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1420: c->flags |= SSH_SOCKS5_AUTHDONE;
1421: debug2("channel %d: socks5 auth done", c->self);
1422: return 0; /* need more */
1423: }
1424: debug2("channel %d: socks5 post auth", c->self);
1425: if (have < sizeof(s5_req)+1)
1426: return 0; /* need more */
1.247 deraadt 1427: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1428: if (s5_req.version != 0x05 ||
1429: s5_req.command != SSH_SOCKS5_CONNECT ||
1430: s5_req.reserved != 0x00) {
1.194 markus 1431: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1432: return -1;
1433: }
1.213 deraadt 1434: switch (s5_req.atyp){
1.193 markus 1435: case SSH_SOCKS5_IPV4:
1436: addrlen = 4;
1437: af = AF_INET;
1438: break;
1439: case SSH_SOCKS5_DOMAIN:
1440: addrlen = p[sizeof(s5_req)];
1441: af = -1;
1442: break;
1443: case SSH_SOCKS5_IPV6:
1444: addrlen = 16;
1445: af = AF_INET6;
1446: break;
1447: default:
1.194 markus 1448: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1449: return -1;
1450: }
1.252 djm 1451: need = sizeof(s5_req) + addrlen + 2;
1452: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1453: need++;
1454: if (have < need)
1.193 markus 1455: return 0;
1.403 djm 1456: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0)
1457: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1458: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1459: /* host string length */
1.403 djm 1460: if ((r = sshbuf_consume(input, 1)) != 0)
1461: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1462: }
1.372 markus 1463: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1464: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.403 djm 1465: debug_r(r, "channel %d: parse addr/port", c->self);
1.367 djm 1466: return -1;
1467: }
1.193 markus 1468: dest_addr[addrlen] = '\0';
1.321 djm 1469: free(c->path);
1470: c->path = NULL;
1.293 djm 1471: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1472: if (addrlen >= NI_MAXHOST) {
1.293 djm 1473: error("channel %d: dynamic request: socks5 hostname "
1474: "\"%.100s\" too long", c->self, dest_addr);
1475: return -1;
1476: }
1477: c->path = xstrdup(dest_addr);
1478: } else {
1479: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1480: return -1;
1481: c->path = xstrdup(ntop);
1482: }
1.193 markus 1483: c->host_port = ntohs(dest_port);
1.198 djm 1484:
1.194 markus 1485: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1486: c->self, c->path, c->host_port, s5_req.command);
1487:
1488: s5_rsp.version = 0x05;
1489: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1490: s5_rsp.reserved = 0; /* ignored */
1491: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1492: dest_port = 0; /* ignored */
1493:
1.372 markus 1494: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1495: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1496: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.403 djm 1497: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1498: return 1;
1.301 dtucker 1499: }
1500:
1501: Channel *
1.367 djm 1502: channel_connect_stdio_fwd(struct ssh *ssh,
1.407 djm 1503: const char *host_to_connect, u_short port_to_connect,
1504: int in, int out, int nonblock)
1.301 dtucker 1505: {
1506: Channel *c;
1507:
1.403 djm 1508: debug_f("%s:%d", host_to_connect, port_to_connect);
1.301 dtucker 1509:
1.367 djm 1510: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1511: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.407 djm 1512: 0, "stdio-forward", nonblock);
1.301 dtucker 1513:
1514: c->path = xstrdup(host_to_connect);
1515: c->host_port = port_to_connect;
1516: c->listening_port = 0;
1517: c->force_drain = 1;
1518:
1.367 djm 1519: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1520: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1521:
1522: return c;
1.193 markus 1523: }
1524:
1.104 markus 1525: /* dynamic port forwarding */
1.127 itojun 1526: static void
1.410 djm 1527: channel_pre_dynamic(struct ssh *ssh, Channel *c)
1.104 markus 1528: {
1.367 djm 1529: const u_char *p;
1.217 djm 1530: u_int have;
1531: int ret;
1.103 markus 1532:
1.410 djm 1533: c->io_want = 0;
1.367 djm 1534: have = sshbuf_len(c->input);
1.104 markus 1535: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1536: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1537: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1538: if (have < 3) {
1.104 markus 1539: /* need more */
1.410 djm 1540: c->io_want |= SSH_CHAN_IO_RFD;
1.104 markus 1541: return;
1542: }
1543: /* try to guess the protocol */
1.367 djm 1544: p = sshbuf_ptr(c->input);
1545: /* XXX sshbuf_peek_u8? */
1.104 markus 1546: switch (p[0]) {
1547: case 0x04:
1.372 markus 1548: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1549: break;
1550: case 0x05:
1.372 markus 1551: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1552: break;
1553: default:
1554: ret = -1;
1555: break;
1556: }
1557: if (ret < 0) {
1.367 djm 1558: chan_mark_dead(ssh, c);
1.104 markus 1559: } else if (ret == 0) {
1560: debug2("channel %d: pre_dynamic: need more", c->self);
1561: /* need more */
1.410 djm 1562: c->io_want |= SSH_CHAN_IO_RFD;
1.372 markus 1563: if (sshbuf_len(c->output))
1.410 djm 1564: c->io_want |= SSH_CHAN_IO_WFD;
1.104 markus 1565: } else {
1566: /* switch to the next state */
1567: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1568: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1569: }
1.103 markus 1570: }
1571:
1.372 markus 1572: /* simulate read-error */
1573: static void
1574: rdynamic_close(struct ssh *ssh, Channel *c)
1575: {
1576: c->type = SSH_CHANNEL_OPEN;
1577: chan_read_failed(ssh, c);
1578: sshbuf_reset(c->input);
1579: chan_ibuf_empty(ssh, c);
1580: sshbuf_reset(c->output);
1581: chan_write_failed(ssh, c);
1582: }
1583:
1584: /* reverse dynamic port forwarding */
1585: static void
1.411 djm 1586: channel_before_prepare_io_rdynamic(struct ssh *ssh, Channel *c)
1.372 markus 1587: {
1588: const u_char *p;
1589: u_int have, len;
1590: int r, ret;
1591:
1592: have = sshbuf_len(c->output);
1593: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1594: /* sshbuf_dump(c->output, stderr); */
1595: /* EOF received */
1596: if (c->flags & CHAN_EOF_RCVD) {
1.403 djm 1597: if ((r = sshbuf_consume(c->output, have)) != 0)
1598: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1599: rdynamic_close(ssh, c);
1600: return;
1601: }
1602: /* check if the fixed size part of the packet is in buffer. */
1603: if (have < 3)
1604: return;
1605: /* try to guess the protocol */
1606: p = sshbuf_ptr(c->output);
1607: switch (p[0]) {
1608: case 0x04:
1609: /* switch input/output for reverse forwarding */
1610: ret = channel_decode_socks4(c, c->output, c->input);
1611: break;
1612: case 0x05:
1613: ret = channel_decode_socks5(c, c->output, c->input);
1614: break;
1615: default:
1616: ret = -1;
1617: break;
1618: }
1619: if (ret < 0) {
1620: rdynamic_close(ssh, c);
1621: } else if (ret == 0) {
1622: debug2("channel %d: pre_rdynamic: need more", c->self);
1623: /* send socks request to peer */
1624: len = sshbuf_len(c->input);
1625: if (len > 0 && len < c->remote_window) {
1626: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1627: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1628: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1629: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 1630: fatal_fr(r, "channel %i: rdynamic", c->self);
1.372 markus 1631: }
1.403 djm 1632: if ((r = sshbuf_consume(c->input, len)) != 0)
1633: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1634: c->remote_window -= len;
1635: }
1636: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1637: /* the connect failed */
1638: rdynamic_close(ssh, c);
1639: }
1640: }
1641:
1.41 markus 1642: /* This is our fake X11 server socket. */
1.127 itojun 1643: static void
1.410 djm 1644: channel_post_x11_listener(struct ssh *ssh, Channel *c)
1.41 markus 1645: {
1.113 markus 1646: Channel *nc;
1.285 djm 1647: struct sockaddr_storage addr;
1.367 djm 1648: int r, newsock, oerrno, remote_port;
1.41 markus 1649: socklen_t addrlen;
1.85 markus 1650: char buf[16384], *remote_ipaddr;
1.25 markus 1651:
1.410 djm 1652: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1653: return;
1654:
1655: debug("X11 connection requested.");
1656: addrlen = sizeof(addr);
1657: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1658: if (c->single_connection) {
1659: oerrno = errno;
1660: debug2("single_connection: closing X11 listener.");
1.407 djm 1661: channel_close_fd(ssh, c, &c->sock);
1.367 djm 1662: chan_mark_dead(ssh, c);
1663: errno = oerrno;
1664: }
1.393 deraadt 1665: if (newsock == -1) {
1.367 djm 1666: if (errno != EINTR && errno != EWOULDBLOCK &&
1667: errno != ECONNABORTED)
1668: error("accept: %.100s", strerror(errno));
1669: if (errno == EMFILE || errno == ENFILE)
1670: c->notbefore = monotime() + 1;
1671: return;
1672: }
1673: set_nodelay(newsock);
1674: remote_ipaddr = get_peer_ipaddr(newsock);
1675: remote_port = get_peer_port(newsock);
1676: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1677: remote_ipaddr, remote_port);
1678:
1679: nc = channel_new(ssh, "accepted x11 socket",
1680: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1681: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1682: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1683: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1684: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.403 djm 1685: fatal_fr(r, "channel %i: reply", c->self);
1.41 markus 1686: }
1.367 djm 1687: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1688: fatal_fr(r, "channel %i: send", c->self);
1.367 djm 1689: free(remote_ipaddr);
1.41 markus 1690: }
1.25 markus 1691:
1.127 itojun 1692: static void
1.367 djm 1693: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1694: {
1.328 djm 1695: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1696: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1697: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1698: int remote_port = get_peer_port(c->sock);
1.367 djm 1699: int r;
1.303 djm 1700:
1701: if (remote_port == -1) {
1702: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1703: free(remote_ipaddr);
1.303 djm 1704: remote_ipaddr = xstrdup("127.0.0.1");
1705: remote_port = 65535;
1706: }
1.103 markus 1707:
1.367 djm 1708: free(c->remote_name);
1709: xasprintf(&c->remote_name,
1.103 markus 1710: "%s: listening port %d for %.100s port %d, "
1.328 djm 1711: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1712: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1713: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1714:
1.367 djm 1715: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1716: if (strcmp(rtype, "direct-tcpip") == 0) {
1717: /* target host, port */
1.367 djm 1718: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1719: (r = sshpkt_put_u32(ssh, c->host_port)) != 0)
1720: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1721: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1722: /* target path */
1.403 djm 1723: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1724: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1725: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1726: /* listen path */
1.403 djm 1727: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1728: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1729: } else {
1.358 djm 1730: /* listen address, port */
1.367 djm 1731: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1732: (r = sshpkt_put_u32(ssh, local_port)) != 0)
1733: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1734: }
1735: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1736: /* reserved for future owner/mode info */
1.403 djm 1737: if ((r = sshpkt_put_cstring(ssh, "")) != 0)
1738: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1739: } else {
1740: /* originator host and port */
1.367 djm 1741: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1.403 djm 1742: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0)
1743: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1744: }
1.367 djm 1745: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1746: fatal_fr(r, "channel %i: send", c->self);
1.321 djm 1747: free(remote_ipaddr);
1.328 djm 1748: free(local_ipaddr);
1.103 markus 1749: }
1750:
1.347 djm 1751: void
1.367 djm 1752: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1753: {
1.367 djm 1754: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1755: }
1756:
1.41 markus 1757: /*
1758: * This socket is listening for connections to a forwarded TCP/IP port.
1759: */
1.127 itojun 1760: static void
1.410 djm 1761: channel_post_port_listener(struct ssh *ssh, Channel *c)
1.41 markus 1762: {
1.103 markus 1763: Channel *nc;
1.285 djm 1764: struct sockaddr_storage addr;
1.113 markus 1765: int newsock, nextstate;
1.41 markus 1766: socklen_t addrlen;
1.103 markus 1767: char *rtype;
1.73 markus 1768:
1.410 djm 1769: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1770: return;
1771:
1772: debug("Connection to port %d forwarding to %.100s port %d requested.",
1773: c->listening_port, c->path, c->host_port);
1.103 markus 1774:
1.367 djm 1775: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1776: nextstate = SSH_CHANNEL_OPENING;
1777: rtype = "forwarded-tcpip";
1778: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1779: nextstate = SSH_CHANNEL_OPENING;
1780: rtype = "forwarded-streamlocal@openssh.com";
1781: } else if (c->host_port == PORT_STREAMLOCAL) {
1782: nextstate = SSH_CHANNEL_OPENING;
1783: rtype = "direct-streamlocal@openssh.com";
1784: } else if (c->host_port == 0) {
1785: nextstate = SSH_CHANNEL_DYNAMIC;
1786: rtype = "dynamic-tcpip";
1787: } else {
1788: nextstate = SSH_CHANNEL_OPENING;
1789: rtype = "direct-tcpip";
1790: }
1.103 markus 1791:
1.367 djm 1792: addrlen = sizeof(addr);
1793: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1794: if (newsock == -1) {
1.367 djm 1795: if (errno != EINTR && errno != EWOULDBLOCK &&
1796: errno != ECONNABORTED)
1797: error("accept: %.100s", strerror(errno));
1798: if (errno == EMFILE || errno == ENFILE)
1799: c->notbefore = monotime() + 1;
1800: return;
1.41 markus 1801: }
1.367 djm 1802: if (c->host_port != PORT_STREAMLOCAL)
1803: set_nodelay(newsock);
1804: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1805: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1806: nc->listening_port = c->listening_port;
1807: nc->host_port = c->host_port;
1808: if (c->path != NULL)
1809: nc->path = xstrdup(c->path);
1810:
1811: if (nextstate != SSH_CHANNEL_DYNAMIC)
1812: port_open_helper(ssh, nc, rtype);
1.41 markus 1813: }
1.25 markus 1814:
1.41 markus 1815: /*
1816: * This is the authentication agent socket listening for connections from
1817: * clients.
1818: */
1.127 itojun 1819: static void
1.410 djm 1820: channel_post_auth_listener(struct ssh *ssh, Channel *c)
1.41 markus 1821: {
1.113 markus 1822: Channel *nc;
1.367 djm 1823: int r, newsock;
1.285 djm 1824: struct sockaddr_storage addr;
1.41 markus 1825: socklen_t addrlen;
1.25 markus 1826:
1.410 djm 1827: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1828: return;
1829:
1830: addrlen = sizeof(addr);
1831: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1832: if (newsock == -1) {
1.367 djm 1833: error("accept from auth socket: %.100s", strerror(errno));
1834: if (errno == EMFILE || errno == ENFILE)
1835: c->notbefore = monotime() + 1;
1836: return;
1.41 markus 1837: }
1.367 djm 1838: nc = channel_new(ssh, "accepted auth socket",
1839: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1840: c->local_window_max, c->local_maxpacket,
1841: 0, "accepted auth socket", 1);
1842: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1843: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1844: fatal_fr(r, "channel %i", c->self);
1.41 markus 1845: }
1.25 markus 1846:
1.127 itojun 1847: static void
1.410 djm 1848: channel_post_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1849: {
1.372 markus 1850: int err = 0, sock, isopen, r;
1.129 stevesk 1851: socklen_t sz = sizeof(err);
1.114 markus 1852:
1.410 djm 1853: if ((c->io_ready & SSH_CHAN_IO_SOCK_W) == 0)
1.367 djm 1854: return;
1.368 djm 1855: if (!c->have_remote_id)
1.403 djm 1856: fatal_f("channel %d: no remote id", c->self);
1.372 markus 1857: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1858: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.393 deraadt 1859: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 1860: err = errno;
1861: error("getsockopt SO_ERROR failed");
1862: }
1863: if (err == 0) {
1864: debug("channel %d: connected to %s port %d",
1865: c->self, c->connect_ctx.host, c->connect_ctx.port);
1866: channel_connect_ctx_free(&c->connect_ctx);
1867: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1868: if (isopen) {
1869: /* no message necessary */
1870: } else {
1871: if ((r = sshpkt_start(ssh,
1872: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1873: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1874: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1875: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 1876: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0 ||
1877: (r = sshpkt_send(ssh)) != 0)
1878: fatal_fr(r, "channel %i open confirm", c->self);
1.367 djm 1879: }
1880: } else {
1881: debug("channel %d: connection failed: %s",
1882: c->self, strerror(err));
1883: /* Try next address, if any */
1884: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1885: close(c->sock);
1886: c->sock = c->rfd = c->wfd = sock;
1887: return;
1888: }
1889: /* Exhausted all addresses */
1890: error("connect_to %.100s port %d: failed.",
1891: c->connect_ctx.host, c->connect_ctx.port);
1892: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1893: if (isopen) {
1894: rdynamic_close(ssh, c);
1895: } else {
1896: if ((r = sshpkt_start(ssh,
1897: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1898: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 1899: (r = sshpkt_put_u32(ssh,
1900: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
1901: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1.403 djm 1902: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1903: (r = sshpkt_send(ssh)) != 0)
1904: fatal_fr(r, "channel %i: failure", c->self);
1.372 markus 1905: chan_mark_dead(ssh, c);
1.75 markus 1906: }
1907: }
1908: }
1909:
1.127 itojun 1910: static int
1.410 djm 1911: channel_handle_rfd(struct ssh *ssh, Channel *c)
1.41 markus 1912: {
1.214 markus 1913: char buf[CHAN_RBUF];
1.367 djm 1914: ssize_t len;
1915: int r;
1.412 djm 1916: size_t have, avail, maxlen = CHANNEL_MAX_READ;
1.25 markus 1917:
1.410 djm 1918: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.412 djm 1919: return 1; /* Shouldn't happen */
1920: if ((avail = sshbuf_avail(c->input)) == 0)
1921: return 1; /* Shouldn't happen */
1922:
1923: /*
1924: * For "simple" channels (i.e. not datagram or filtered), we can
1925: * read directly to the channel buffer.
1926: */
1927: if (c->input_filter == NULL && !c->datagram) {
1928: /* Only OPEN channels have valid rwin */
1929: if (c->type == SSH_CHANNEL_OPEN) {
1930: if ((have = sshbuf_len(c->input)) >= c->remote_window)
1931: return 1; /* shouldn't happen */
1932: if (maxlen > c->remote_window - have)
1933: maxlen = c->remote_window - have;
1934: }
1935: if (maxlen > avail)
1936: maxlen = avail;
1937: if ((r = sshbuf_read(c->rfd, c->input, maxlen, NULL)) != 0) {
1.413 djm 1938: if (errno == EINTR || errno == EAGAIN)
1939: return 1;
1.412 djm 1940: debug2("channel %d: read failed rfd %d maxlen %zu: %s",
1941: c->self, c->rfd, maxlen, ssh_err(r));
1942: goto rfail;
1943: }
1.367 djm 1944: return 1;
1.412 djm 1945: }
1.367 djm 1946:
1947: len = read(c->rfd, buf, sizeof(buf));
1.393 deraadt 1948: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 1949: return 1;
1950: if (len <= 0) {
1.412 djm 1951: debug2("channel %d: read<=0 rfd %d len %zd: %s",
1952: c->self, c->rfd, len,
1953: len == 0 ? "closed" : strerror(errno));
1954: rfail:
1.367 djm 1955: if (c->type != SSH_CHANNEL_OPEN) {
1956: debug2("channel %d: not open", c->self);
1957: chan_mark_dead(ssh, c);
1.41 markus 1958: return -1;
1.65 markus 1959: } else {
1.367 djm 1960: chan_read_failed(ssh, c);
1.65 markus 1961: }
1.367 djm 1962: return -1;
1963: }
1964: if (c->input_filter != NULL) {
1965: if (c->input_filter(ssh, c, buf, len) == -1) {
1966: debug2("channel %d: filter stops", c->self);
1967: chan_read_failed(ssh, c);
1968: }
1969: } else if (c->datagram) {
1970: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1.403 djm 1971: fatal_fr(r, "channel %i: put datagram", c->self);
1.412 djm 1972: }
1.41 markus 1973: return 1;
1974: }
1.241 deraadt 1975:
1.127 itojun 1976: static int
1.410 djm 1977: channel_handle_wfd(struct ssh *ssh, Channel *c)
1.41 markus 1978: {
1.95 markus 1979: struct termios tio;
1.367 djm 1980: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1981: size_t dlen, olen = 0;
1982: int r, len;
1983:
1.410 djm 1984: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
1985: return 1;
1986: if (sshbuf_len(c->output) == 0)
1.367 djm 1987: return 1;
1.25 markus 1988:
1.41 markus 1989: /* Send buffered output data to the socket. */
1.367 djm 1990: olen = sshbuf_len(c->output);
1991: if (c->output_filter != NULL) {
1992: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1993: debug2("channel %d: filter stops", c->self);
1994: if (c->type != SSH_CHANNEL_OPEN)
1995: chan_mark_dead(ssh, c);
1996: else
1997: chan_write_failed(ssh, c);
1998: return -1;
1.231 reyk 1999: }
1.367 djm 2000: } else if (c->datagram) {
2001: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1.403 djm 2002: fatal_fr(r, "channel %i: get datagram", c->self);
1.369 djm 2003: buf = data;
1.367 djm 2004: } else {
2005: buf = data = sshbuf_mutable_ptr(c->output);
2006: dlen = sshbuf_len(c->output);
2007: }
1.231 reyk 2008:
1.367 djm 2009: if (c->datagram) {
2010: /* ignore truncated writes, datagrams might get lost */
1.374 djm 2011: len = write(c->wfd, buf, dlen);
1.367 djm 2012: free(data);
1.393 deraadt 2013: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 2014: return 1;
1.367 djm 2015: if (len <= 0)
2016: goto write_fail;
2017: goto out;
2018: }
2019:
2020: len = write(c->wfd, buf, dlen);
1.393 deraadt 2021: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2022: return 1;
2023: if (len <= 0) {
2024: write_fail:
2025: if (c->type != SSH_CHANNEL_OPEN) {
2026: debug2("channel %d: not open", c->self);
2027: chan_mark_dead(ssh, c);
1.41 markus 2028: return -1;
1.367 djm 2029: } else {
2030: chan_write_failed(ssh, c);
1.91 markus 2031: }
1.367 djm 2032: return -1;
2033: }
2034: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2035: if (tcgetattr(c->wfd, &tio) == 0 &&
2036: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2037: /*
2038: * Simulate echo to reduce the impact of
2039: * traffic analysis. We need to match the
2040: * size of a SSH2_MSG_CHANNEL_DATA message
2041: * (4 byte channel id + buf)
2042: */
2043: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2044: (r = sshpkt_send(ssh)) != 0)
1.403 djm 2045: fatal_fr(r, "channel %i: ignore", c->self);
1.25 markus 2046: }
1.367 djm 2047: }
1.403 djm 2048: if ((r = sshbuf_consume(c->output, len)) != 0)
2049: fatal_fr(r, "channel %i: consume", c->self);
1.309 djm 2050: out:
1.367 djm 2051: c->local_consumed += olen - sshbuf_len(c->output);
2052:
2053: return 1;
2054: }
2055:
2056: static int
1.410 djm 2057: channel_handle_efd_write(struct ssh *ssh, Channel *c)
1.367 djm 2058: {
2059: int r;
2060: ssize_t len;
2061:
1.410 djm 2062: if ((c->io_ready & SSH_CHAN_IO_EFD_W) == 0)
2063: return 1;
2064: if (sshbuf_len(c->extended) == 0)
1.367 djm 2065: return 1;
2066:
2067: len = write(c->efd, sshbuf_ptr(c->extended),
2068: sshbuf_len(c->extended));
2069: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 deraadt 2070: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2071: return 1;
2072: if (len <= 0) {
2073: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1.407 djm 2074: channel_close_fd(ssh, c, &c->efd);
1.367 djm 2075: } else {
1.403 djm 2076: if ((r = sshbuf_consume(c->extended, len)) != 0)
2077: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2078: c->local_consumed += len;
2079: }
1.44 markus 2080: return 1;
2081: }
1.241 deraadt 2082:
1.127 itojun 2083: static int
1.410 djm 2084: channel_handle_efd_read(struct ssh *ssh, Channel *c)
1.44 markus 2085: {
1.214 markus 2086: char buf[CHAN_RBUF];
1.367 djm 2087: int r;
2088: ssize_t len;
2089:
1.410 djm 2090: if ((c->io_ready & SSH_CHAN_IO_EFD_R) == 0)
1.367 djm 2091: return 1;
1.44 markus 2092:
1.367 djm 2093: len = read(c->efd, buf, sizeof(buf));
2094: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 deraadt 2095: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2096: return 1;
2097: if (len <= 0) {
1.403 djm 2098: debug2("channel %d: closing read-efd %d", c->self, c->efd);
1.407 djm 2099: channel_close_fd(ssh, c, &c->efd);
1.403 djm 2100: } else if (c->extended_usage == CHAN_EXTENDED_IGNORE)
2101: debug3("channel %d: discard efd", c->self);
2102: else if ((r = sshbuf_put(c->extended, buf, len)) != 0)
2103: fatal_fr(r, "channel %i: append", c->self);
1.44 markus 2104: return 1;
2105: }
1.241 deraadt 2106:
1.127 itojun 2107: static int
1.410 djm 2108: channel_handle_efd(struct ssh *ssh, Channel *c)
1.44 markus 2109: {
1.367 djm 2110: if (c->efd == -1)
2111: return 1;
2112:
2113: /** XXX handle drain efd, too */
2114:
2115: if (c->extended_usage == CHAN_EXTENDED_WRITE)
1.410 djm 2116: return channel_handle_efd_write(ssh, c);
1.367 djm 2117: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2118: c->extended_usage == CHAN_EXTENDED_IGNORE)
1.410 djm 2119: return channel_handle_efd_read(ssh, c);
1.367 djm 2120:
2121: return 1;
2122: }
2123:
2124: static int
2125: channel_check_window(struct ssh *ssh, Channel *c)
2126: {
2127: int r;
2128:
1.104 markus 2129: if (c->type == SSH_CHANNEL_OPEN &&
2130: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2131: ((c->local_window_max - c->local_window >
1.269 markus 2132: c->local_maxpacket*3) ||
2133: c->local_window < c->local_window_max/2) &&
1.44 markus 2134: c->local_consumed > 0) {
1.368 djm 2135: if (!c->have_remote_id)
1.403 djm 2136: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2137: if ((r = sshpkt_start(ssh,
2138: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2139: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2140: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2141: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2142: fatal_fr(r, "channel %i", c->self);
1.367 djm 2143: }
1.403 djm 2144: debug2("channel %d: window %d sent adjust %d", c->self,
2145: c->local_window, c->local_consumed);
1.44 markus 2146: c->local_window += c->local_consumed;
2147: c->local_consumed = 0;
1.1 deraadt 2148: }
1.41 markus 2149: return 1;
1.1 deraadt 2150: }
2151:
1.127 itojun 2152: static void
1.410 djm 2153: channel_post_open(struct ssh *ssh, Channel *c)
1.41 markus 2154: {
1.410 djm 2155: channel_handle_rfd(ssh, c);
2156: channel_handle_wfd(ssh, c);
2157: channel_handle_efd(ssh, c);
1.367 djm 2158: channel_check_window(ssh, c);
1.44 markus 2159: }
2160:
1.302 djm 2161: static u_int
1.367 djm 2162: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2163: {
2164: char buf[CHAN_RBUF];
1.367 djm 2165: ssize_t len;
1.302 djm 2166: u_int rlen;
1.367 djm 2167: int r;
1.302 djm 2168:
1.367 djm 2169: if (sshbuf_len(c->input) < need) {
2170: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2171: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 deraadt 2172: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2173: return sshbuf_len(c->input);
1.302 djm 2174: if (len <= 0) {
1.367 djm 2175: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2176: c->self, c->rfd, len);
1.367 djm 2177: chan_read_failed(ssh, c);
1.349 naddy 2178: return 0;
1.403 djm 2179: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
2180: fatal_fr(r, "channel %i: append", c->self);
1.302 djm 2181: }
1.367 djm 2182: return sshbuf_len(c->input);
1.302 djm 2183: }
2184:
2185: static void
1.410 djm 2186: channel_post_mux_client_read(struct ssh *ssh, Channel *c)
1.302 djm 2187: {
2188: u_int need;
2189:
1.410 djm 2190: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.367 djm 2191: return;
2192: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2193: return;
2194: if (c->mux_pause)
2195: return;
2196:
2197: /*
2198: * Don't not read past the precise end of packets to
2199: * avoid disrupting fd passing.
2200: */
2201: if (read_mux(ssh, c, 4) < 4) /* read header */
2202: return;
2203: /* XXX sshbuf_peek_u32 */
2204: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2205: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2206: if (need > CHANNEL_MUX_MAX_PACKET) {
2207: debug2("channel %d: packet too big %u > %u",
2208: c->self, CHANNEL_MUX_MAX_PACKET, need);
2209: chan_rcvd_oclose(ssh, c);
2210: return;
2211: }
2212: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2213: return;
2214: if (c->mux_rcb(ssh, c) != 0) {
2215: debug("channel %d: mux_rcb failed", c->self);
2216: chan_mark_dead(ssh, c);
2217: return;
1.302 djm 2218: }
1.367 djm 2219: }
2220:
2221: static void
1.410 djm 2222: channel_post_mux_client_write(struct ssh *ssh, Channel *c)
1.367 djm 2223: {
2224: ssize_t len;
2225: int r;
1.302 djm 2226:
1.410 djm 2227: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
2228: return;
2229: if (sshbuf_len(c->output) == 0)
1.367 djm 2230: return;
2231:
2232: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 deraadt 2233: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2234: return;
2235: if (len <= 0) {
2236: chan_mark_dead(ssh, c);
2237: return;
1.302 djm 2238: }
1.367 djm 2239: if ((r = sshbuf_consume(c->output, len)) != 0)
1.403 djm 2240: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2241: }
2242:
2243: static void
1.410 djm 2244: channel_post_mux_client(struct ssh *ssh, Channel *c)
1.367 djm 2245: {
1.410 djm 2246: channel_post_mux_client_read(ssh, c);
2247: channel_post_mux_client_write(ssh, c);
1.302 djm 2248: }
2249:
2250: static void
1.410 djm 2251: channel_post_mux_listener(struct ssh *ssh, Channel *c)
1.302 djm 2252: {
2253: Channel *nc;
2254: struct sockaddr_storage addr;
2255: socklen_t addrlen;
2256: int newsock;
2257: uid_t euid;
2258: gid_t egid;
2259:
1.410 djm 2260: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.302 djm 2261: return;
2262:
2263: debug("multiplexing control connection");
2264:
2265: /*
2266: * Accept connection on control socket
2267: */
2268: memset(&addr, 0, sizeof(addr));
2269: addrlen = sizeof(addr);
2270: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2271: &addrlen)) == -1) {
1.403 djm 2272: error_f("accept: %s", strerror(errno));
1.317 djm 2273: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2274: c->notbefore = monotime() + 1;
1.302 djm 2275: return;
2276: }
2277:
1.393 deraadt 2278: if (getpeereid(newsock, &euid, &egid) == -1) {
1.403 djm 2279: error_f("getpeereid failed: %s", strerror(errno));
1.302 djm 2280: close(newsock);
2281: return;
2282: }
2283: if ((euid != 0) && (getuid() != euid)) {
2284: error("multiplex uid mismatch: peer euid %u != uid %u",
2285: (u_int)euid, (u_int)getuid());
2286: close(newsock);
2287: return;
2288: }
1.367 djm 2289: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2290: newsock, newsock, -1, c->local_window_max,
2291: c->local_maxpacket, 0, "mux-control", 1);
2292: nc->mux_rcb = c->mux_rcb;
1.403 djm 2293: debug3_f("new mux channel %d fd %d", nc->self, nc->sock);
1.302 djm 2294: /* establish state */
1.367 djm 2295: nc->mux_rcb(ssh, nc);
1.302 djm 2296: /* mux state transitions must not elicit protocol messages */
2297: nc->flags |= CHAN_LOCAL;
2298: }
2299:
1.127 itojun 2300: static void
1.367 djm 2301: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2302: {
1.367 djm 2303: chan_fn **pre, **post;
2304:
2305: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
1.406 djm 2306: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
1.403 djm 2307: fatal_f("allocation failed");
1.367 djm 2308:
2309: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2310: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2311: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2312: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2313: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2314: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2315: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2316: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2317: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2318: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2319: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2320: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2321: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2322:
2323: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2324: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2325: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2326: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2327: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2328: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2329: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2330: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2331: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2332: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2333: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2334: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2335:
1.367 djm 2336: sc->channel_pre = pre;
2337: sc->channel_post = post;
1.44 markus 2338: }
2339:
1.140 markus 2340: /* gc dead channels */
2341: static void
1.367 djm 2342: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2343: {
2344: if (c == NULL)
2345: return;
2346: if (c->detach_user != NULL) {
1.367 djm 2347: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2348: return;
1.385 djm 2349:
1.194 markus 2350: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2351: c->detach_user(ssh, c->self, NULL);
1.140 markus 2352: /* if we still have a callback */
2353: if (c->detach_user != NULL)
2354: return;
1.194 markus 2355: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2356: }
1.367 djm 2357: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2358: return;
1.194 markus 2359: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2360: channel_free(ssh, c);
1.140 markus 2361: }
2362:
1.367 djm 2363: enum channel_table { CHAN_PRE, CHAN_POST };
2364:
1.127 itojun 2365: static void
1.410 djm 2366: channel_handler(struct ssh *ssh, int table, time_t *unpause_secs)
1.41 markus 2367: {
1.367 djm 2368: struct ssh_channels *sc = ssh->chanctxt;
2369: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2370: u_int i, oalloc;
1.41 markus 2371: Channel *c;
1.317 djm 2372: time_t now;
1.25 markus 2373:
1.322 dtucker 2374: now = monotime();
1.317 djm 2375: if (unpause_secs != NULL)
2376: *unpause_secs = 0;
1.367 djm 2377: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2378: c = sc->channels[i];
1.113 markus 2379: if (c == NULL)
1.41 markus 2380: continue;
1.417 ! djm 2381: /* Try to keep IO going while rekeying */
! 2382: if (ssh_packet_is_rekeying(ssh) && c->type != SSH_CHANNEL_OPEN)
! 2383: continue;
1.299 markus 2384: if (c->delayed) {
1.367 djm 2385: if (table == CHAN_PRE)
1.299 markus 2386: c->delayed = 0;
2387: else
2388: continue;
2389: }
1.317 djm 2390: if (ftab[c->type] != NULL) {
2391: /*
2392: * Run handlers that are not paused.
2393: */
2394: if (c->notbefore <= now)
1.410 djm 2395: (*ftab[c->type])(ssh, c);
1.317 djm 2396: else if (unpause_secs != NULL) {
2397: /*
2398: * Collect the time that the earliest
2399: * channel comes off pause.
2400: */
1.403 djm 2401: debug3_f("chan %d: skip for %d more "
2402: "seconds", c->self,
1.317 djm 2403: (int)(c->notbefore - now));
2404: if (*unpause_secs == 0 ||
2405: (c->notbefore - now) < *unpause_secs)
2406: *unpause_secs = c->notbefore - now;
2407: }
2408: }
1.367 djm 2409: channel_garbage_collect(ssh, c);
1.1 deraadt 2410: }
1.317 djm 2411: if (unpause_secs != NULL && *unpause_secs != 0)
1.403 djm 2412: debug3_f("first channel unpauses in %d seconds",
2413: (int)*unpause_secs);
1.1 deraadt 2414: }
2415:
1.121 markus 2416: /*
1.411 djm 2417: * Create sockets before preparing IO.
1.372 markus 2418: * This is necessary for things that need to happen after reading
1.411 djm 2419: * the network-input but need to be completed before IO event setup, e.g.
2420: * because they may create new channels.
1.372 markus 2421: */
2422: static void
1.411 djm 2423: channel_before_prepare_io(struct ssh *ssh)
1.372 markus 2424: {
2425: struct ssh_channels *sc = ssh->chanctxt;
2426: Channel *c;
2427: u_int i, oalloc;
2428:
2429: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2430: c = sc->channels[i];
2431: if (c == NULL)
2432: continue;
2433: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
1.411 djm 2434: channel_before_prepare_io_rdynamic(ssh, c);
2435: }
2436: }
2437:
2438: static void
2439: dump_channel_poll(const char *func, const char *what, Channel *c,
2440: u_int pollfd_offset, struct pollfd *pfd)
2441: {
2442: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2443: debug3("%s: channel %d: %s r%d w%d e%d s%d c->pfds [ %d %d %d %d ] "
2444: "io_want 0x%02x io_ready 0x%02x pfd[%u].fd=%d "
2445: "pfd.ev 0x%02x pfd.rev 0x%02x", func, c->self, what,
2446: c->rfd, c->wfd, c->efd, c->sock,
2447: c->pfds[0], c->pfds[1], c->pfds[2], c->pfds[3],
2448: c->io_want, c->io_ready,
2449: pollfd_offset, pfd->fd, pfd->events, pfd->revents);
1.411 djm 2450: #endif
2451: }
2452:
2453: /* Prepare pollfd entries for a single channel */
2454: static void
2455: channel_prepare_pollfd(Channel *c, u_int *next_pollfd,
2456: struct pollfd *pfd, u_int npfd)
2457: {
1.415 djm 2458: u_int ev, p = *next_pollfd;
1.411 djm 2459:
2460: if (c == NULL)
2461: return;
2462: if (p + 4 > npfd) {
2463: /* Shouldn't happen */
2464: fatal_f("channel %d: bad pfd offset %u (max %u)",
2465: c->self, p, npfd);
2466: }
1.415 djm 2467: c->pfds[0] = c->pfds[1] = c->pfds[2] = c->pfds[3] = -1;
1.411 djm 2468: /*
2469: * prepare c->rfd
2470: *
2471: * This is a special case, since c->rfd might be the same as
2472: * c->wfd, c->efd and/or c->sock. Handle those here if they want
2473: * IO too.
2474: */
2475: if (c->rfd != -1) {
1.415 djm 2476: ev = 0;
1.411 djm 2477: if ((c->io_want & SSH_CHAN_IO_RFD) != 0)
1.415 djm 2478: ev |= POLLIN;
1.411 djm 2479: /* rfd == wfd */
1.415 djm 2480: if (c->wfd == c->rfd) {
2481: if ((c->io_want & SSH_CHAN_IO_WFD) != 0)
2482: ev |= POLLOUT;
2483: }
1.411 djm 2484: /* rfd == efd */
1.415 djm 2485: if (c->efd == c->rfd) {
2486: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
2487: ev |= POLLIN;
2488: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
2489: ev |= POLLOUT;
2490: }
1.411 djm 2491: /* rfd == sock */
1.415 djm 2492: if (c->sock == c->rfd) {
2493: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
2494: ev |= POLLIN;
2495: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
2496: ev |= POLLOUT;
2497: }
2498: /* Pack a pfd entry if any event armed for this fd */
2499: if (ev != 0) {
2500: c->pfds[0] = p;
2501: pfd[p].fd = c->rfd;
2502: pfd[p].events = ev;
2503: dump_channel_poll(__func__, "rfd", c, p, &pfd[p]);
2504: p++;
2505: }
1.411 djm 2506: }
1.415 djm 2507: /* prepare c->wfd if wanting IO and not already handled above */
1.411 djm 2508: if (c->wfd != -1 && c->rfd != c->wfd) {
1.415 djm 2509: ev = 0;
2510: if ((c->io_want & SSH_CHAN_IO_WFD))
2511: ev |= POLLOUT;
2512: /* Pack a pfd entry if any event armed for this fd */
2513: if (ev != 0) {
2514: c->pfds[1] = p;
2515: pfd[p].fd = c->wfd;
2516: pfd[p].events = ev;
2517: dump_channel_poll(__func__, "wfd", c, p, &pfd[p]);
2518: p++;
2519: }
1.411 djm 2520: }
1.415 djm 2521: /* prepare c->efd if wanting IO and not already handled above */
1.411 djm 2522: if (c->efd != -1 && c->rfd != c->efd) {
1.415 djm 2523: ev = 0;
1.411 djm 2524: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
1.415 djm 2525: ev |= POLLIN;
1.411 djm 2526: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
1.415 djm 2527: ev |= POLLOUT;
2528: /* Pack a pfd entry if any event armed for this fd */
2529: if (ev != 0) {
2530: c->pfds[2] = p;
2531: pfd[p].fd = c->efd;
2532: pfd[p].events = ev;
2533: dump_channel_poll(__func__, "efd", c, p, &pfd[p]);
2534: p++;
2535: }
1.411 djm 2536: }
1.415 djm 2537: /* prepare c->sock if wanting IO and not already handled above */
1.411 djm 2538: if (c->sock != -1 && c->rfd != c->sock) {
1.415 djm 2539: ev = 0;
1.411 djm 2540: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
1.415 djm 2541: ev |= POLLIN;
1.411 djm 2542: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
1.415 djm 2543: ev |= POLLOUT;
2544: /* Pack a pfd entry if any event armed for this fd */
2545: if (ev != 0) {
2546: c->pfds[3] = p;
2547: pfd[p].fd = c->sock;
2548: pfd[p].events = 0;
2549: dump_channel_poll(__func__, "sock", c, p, &pfd[p]);
2550: p++;
2551: }
1.372 markus 2552: }
1.411 djm 2553: *next_pollfd = p;
1.372 markus 2554: }
2555:
1.411 djm 2556: /* * Allocate/prepare poll structure */
1.49 markus 2557: void
1.411 djm 2558: channel_prepare_poll(struct ssh *ssh, struct pollfd **pfdp, u_int *npfd_allocp,
2559: u_int *npfd_activep, u_int npfd_reserved, time_t *minwait_secs)
1.41 markus 2560: {
1.410 djm 2561: struct ssh_channels *sc = ssh->chanctxt;
1.411 djm 2562: u_int i, oalloc, p, npfd = npfd_reserved;
2563:
2564: channel_before_prepare_io(ssh); /* might create a new channel */
1.416 djm 2565: /* clear out I/O flags from last poll */
2566: for (i = 0; i < sc->channels_alloc; i++) {
2567: if (sc->channels[i] == NULL)
2568: continue;
2569: sc->channels[i]->io_want = sc->channels[i]->io_ready = 0;
2570: }
1.411 djm 2571: /* Allocate 4x pollfd for each channel (rfd, wfd, efd, sock) */
2572: if (sc->channels_alloc >= (INT_MAX / 4) - npfd_reserved)
2573: fatal_f("too many channels"); /* shouldn't happen */
1.417 ! djm 2574: npfd += sc->channels_alloc * 4;
1.411 djm 2575: if (npfd > *npfd_allocp) {
2576: *pfdp = xrecallocarray(*pfdp, *npfd_allocp,
2577: npfd, sizeof(**pfdp));
2578: *npfd_allocp = npfd;
2579: }
2580: *npfd_activep = npfd_reserved;
2581: oalloc = sc->channels_alloc;
1.372 markus 2582:
1.411 djm 2583: channel_handler(ssh, CHAN_PRE, minwait_secs);
1.84 markus 2584:
1.411 djm 2585: if (oalloc != sc->channels_alloc) {
2586: /* shouldn't happen */
2587: fatal_f("channels_alloc changed during CHAN_PRE "
2588: "(was %u, now %u)", oalloc, sc->channels_alloc);
2589: }
1.84 markus 2590:
1.411 djm 2591: /* Prepare pollfd */
2592: p = npfd_reserved;
2593: for (i = 0; i < sc->channels_alloc; i++)
2594: channel_prepare_pollfd(sc->channels[i], &p, *pfdp, npfd);
2595: *npfd_activep = p;
2596: }
2597:
2598: static void
1.415 djm 2599: fd_ready(Channel *c, int p, struct pollfd *pfds, u_int npfd, int fd,
1.411 djm 2600: const char *what, u_int revents_mask, u_int ready)
2601: {
2602: struct pollfd *pfd = &pfds[p];
1.410 djm 2603:
1.411 djm 2604: if (fd == -1)
2605: return;
1.415 djm 2606: if (p == -1 || (u_int)p >= npfd)
2607: fatal_f("channel %d: bad pfd %d (max %u)", c->self, p, npfd);
1.411 djm 2608: dump_channel_poll(__func__, what, c, p, pfd);
2609: if (pfd->fd != fd) {
2610: fatal("channel %d: inconsistent %s fd=%d pollfd[%u].fd %d "
2611: "r%d w%d e%d s%d", c->self, what, fd, p, pfd->fd,
2612: c->rfd, c->wfd, c->efd, c->sock);
2613: }
2614: if ((pfd->revents & POLLNVAL) != 0) {
2615: fatal("channel %d: invalid %s pollfd[%u].fd %d r%d w%d e%d s%d",
2616: c->self, what, p, pfd->fd, c->rfd, c->wfd, c->efd, c->sock);
1.410 djm 2617: }
1.411 djm 2618: if ((pfd->revents & (revents_mask|POLLHUP|POLLERR)) != 0)
2619: c->io_ready |= ready & c->io_want;
1.41 markus 2620: }
2621:
1.121 markus 2622: /*
1.411 djm 2623: * After poll, perform any appropriate operations for channels which have
1.121 markus 2624: * events pending.
2625: */
1.49 markus 2626: void
1.411 djm 2627: channel_after_poll(struct ssh *ssh, struct pollfd *pfd, u_int npfd)
1.41 markus 2628: {
1.410 djm 2629: struct ssh_channels *sc = ssh->chanctxt;
1.415 djm 2630: u_int i;
2631: int p;
1.410 djm 2632: Channel *c;
2633:
1.411 djm 2634: #ifdef DEBUG_CHANNEL_POLL
1.415 djm 2635: for (p = 0; p < (int)npfd; p++) {
1.411 djm 2636: if (pfd[p].revents == 0)
2637: continue;
2638: debug_f("pfd[%u].fd %d rev 0x%04x",
2639: p, pfd[p].fd, pfd[p].revents);
2640: }
2641: #endif
2642:
2643: /* Convert pollfd into c->io_ready */
2644: for (i = 0; i < sc->channels_alloc; i++) {
1.410 djm 2645: c = sc->channels[i];
1.415 djm 2646: if (c == NULL)
1.410 djm 2647: continue;
1.411 djm 2648: /* if rfd is shared with efd/sock then wfd should be too */
2649: if (c->rfd != -1 && c->wfd != -1 && c->rfd != c->wfd &&
2650: (c->rfd == c->efd || c->rfd == c->sock)) {
2651: /* Shouldn't happen */
2652: fatal_f("channel %d: unexpected fds r%d w%d e%d s%d",
2653: c->self, c->rfd, c->wfd, c->efd, c->sock);
2654: }
1.410 djm 2655: c->io_ready = 0;
1.411 djm 2656: /* rfd, potentially shared with wfd, efd and sock */
1.415 djm 2657: if (c->rfd != -1 && (p = c->pfds[0]) != -1) {
2658: fd_ready(c, p, pfd, npfd, c->rfd,
2659: "rfd", POLLIN, SSH_CHAN_IO_RFD);
1.411 djm 2660: if (c->rfd == c->wfd) {
1.415 djm 2661: fd_ready(c, p, pfd, npfd, c->wfd,
2662: "wfd/r", POLLOUT, SSH_CHAN_IO_WFD);
1.411 djm 2663: }
2664: if (c->rfd == c->efd) {
1.415 djm 2665: fd_ready(c, p, pfd, npfd, c->efd,
2666: "efdr/r", POLLIN, SSH_CHAN_IO_EFD_R);
2667: fd_ready(c, p, pfd, npfd, c->efd,
2668: "efdw/r", POLLOUT, SSH_CHAN_IO_EFD_W);
1.411 djm 2669: }
2670: if (c->rfd == c->sock) {
1.415 djm 2671: fd_ready(c, p, pfd, npfd, c->sock,
2672: "sockr/r", POLLIN, SSH_CHAN_IO_SOCK_R);
2673: fd_ready(c, p, pfd, npfd, c->sock,
2674: "sockw/r", POLLOUT, SSH_CHAN_IO_SOCK_W);
1.411 djm 2675: }
1.415 djm 2676: dump_channel_poll(__func__, "rfd", c, p, pfd);
1.411 djm 2677: }
2678: /* wfd */
1.415 djm 2679: if (c->wfd != -1 && c->wfd != c->rfd &&
2680: (p = c->pfds[1]) != -1) {
2681: fd_ready(c, p, pfd, npfd, c->wfd,
2682: "wfd", POLLOUT, SSH_CHAN_IO_WFD);
2683: dump_channel_poll(__func__, "wfd", c, p, pfd);
1.411 djm 2684: }
2685: /* efd */
1.415 djm 2686: if (c->efd != -1 && c->efd != c->rfd &&
2687: (p = c->pfds[2]) != -1) {
2688: fd_ready(c, p, pfd, npfd, c->efd,
2689: "efdr", POLLIN, SSH_CHAN_IO_EFD_R);
2690: fd_ready(c, p, pfd, npfd, c->efd,
2691: "efdw", POLLOUT, SSH_CHAN_IO_EFD_W);
2692: dump_channel_poll(__func__, "efd", c, p, pfd);
1.411 djm 2693: }
2694: /* sock */
1.415 djm 2695: if (c->sock != -1 && c->sock != c->rfd &&
2696: (p = c->pfds[3]) != -1) {
2697: fd_ready(c, p, pfd, npfd, c->sock,
2698: "sockr", POLLIN, SSH_CHAN_IO_SOCK_R);
2699: fd_ready(c, p, pfd, npfd, c->sock,
2700: "sockw", POLLOUT, SSH_CHAN_IO_SOCK_W);
2701: dump_channel_poll(__func__, "sock", c, p, pfd);
1.411 djm 2702: }
1.410 djm 2703: }
2704: channel_handler(ssh, CHAN_POST, NULL);
1.367 djm 2705: }
2706:
2707: /*
2708: * Enqueue data for channels with open or draining c->input.
2709: */
2710: static void
2711: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2712: {
1.373 djm 2713: size_t len, plen;
2714: const u_char *pkt;
1.367 djm 2715: int r;
2716:
2717: if ((len = sshbuf_len(c->input)) == 0) {
2718: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2719: /*
2720: * input-buffer is empty and read-socket shutdown:
2721: * tell peer, that we will not send more data:
2722: * send IEOF.
2723: * hack for extended data: delay EOF if EFD still
2724: * in use.
2725: */
2726: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2727: debug2("channel %d: "
2728: "ibuf_empty delayed efd %d/(%zu)",
2729: c->self, c->efd, sshbuf_len(c->extended));
2730: else
2731: chan_ibuf_empty(ssh, c);
2732: }
2733: return;
2734: }
2735:
1.368 djm 2736: if (!c->have_remote_id)
1.403 djm 2737: fatal_f("channel %d: no remote id", c->self);
1.368 djm 2738:
1.367 djm 2739: if (c->datagram) {
2740: /* Check datagram will fit; drop if not */
1.373 djm 2741: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
1.403 djm 2742: fatal_fr(r, "channel %i: get datagram", c->self);
1.367 djm 2743: /*
2744: * XXX this does tail-drop on the datagram queue which is
2745: * usually suboptimal compared to head-drop. Better to have
2746: * backpressure at read time? (i.e. read + discard)
2747: */
1.373 djm 2748: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2749: debug("channel %d: datagram too big", c->self);
2750: return;
2751: }
2752: /* Enqueue it */
2753: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2754: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2755: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.403 djm 2756: (r = sshpkt_send(ssh)) != 0)
2757: fatal_fr(r, "channel %i: send datagram", c->self);
1.373 djm 2758: c->remote_window -= plen;
1.367 djm 2759: return;
2760: }
2761:
2762: /* Enqueue packet for buffered data. */
2763: if (len > c->remote_window)
2764: len = c->remote_window;
2765: if (len > c->remote_maxpacket)
2766: len = c->remote_maxpacket;
2767: if (len == 0)
2768: return;
2769: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2770: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2771: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
1.403 djm 2772: (r = sshpkt_send(ssh)) != 0)
2773: fatal_fr(r, "channel %i: send data", c->self);
1.367 djm 2774: if ((r = sshbuf_consume(c->input, len)) != 0)
1.403 djm 2775: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2776: c->remote_window -= len;
1.41 markus 2777: }
2778:
1.367 djm 2779: /*
2780: * Enqueue data for channels with open c->extended in read mode.
2781: */
2782: static void
2783: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2784: {
2785: size_t len;
2786: int r;
2787:
2788: if ((len = sshbuf_len(c->extended)) == 0)
2789: return;
2790:
2791: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2792: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2793: if (len > c->remote_window)
2794: len = c->remote_window;
2795: if (len > c->remote_maxpacket)
2796: len = c->remote_maxpacket;
2797: if (len == 0)
2798: return;
1.368 djm 2799: if (!c->have_remote_id)
1.403 djm 2800: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2801: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2802: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2803: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2804: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
1.403 djm 2805: (r = sshpkt_send(ssh)) != 0)
2806: fatal_fr(r, "channel %i: data", c->self);
1.367 djm 2807: if ((r = sshbuf_consume(c->extended, len)) != 0)
1.403 djm 2808: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2809: c->remote_window -= len;
2810: debug2("channel %d: sent ext data %zu", c->self, len);
2811: }
1.121 markus 2812:
1.84 markus 2813: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2814: void
1.367 djm 2815: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2816: {
1.367 djm 2817: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2818: Channel *c;
1.367 djm 2819: u_int i;
1.1 deraadt 2820:
1.367 djm 2821: for (i = 0; i < sc->channels_alloc; i++) {
2822: c = sc->channels[i];
1.113 markus 2823: if (c == NULL)
2824: continue;
1.37 markus 2825:
1.121 markus 2826: /*
2827: * We are only interested in channels that can have buffered
2828: * incoming data.
2829: */
1.358 djm 2830: if (c->type != SSH_CHANNEL_OPEN)
2831: continue;
2832: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2833: /* XXX is this true? */
1.367 djm 2834: debug3("channel %d: will not send data after close",
2835: c->self);
1.44 markus 2836: continue;
2837: }
1.25 markus 2838:
2839: /* Get the amount of buffered data for this channel. */
1.367 djm 2840: if (c->istate == CHAN_INPUT_OPEN ||
2841: c->istate == CHAN_INPUT_WAIT_DRAIN)
2842: channel_output_poll_input_open(ssh, c);
1.44 markus 2843: /* Send extended data, i.e. stderr */
1.358 djm 2844: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2845: c->extended_usage == CHAN_EXTENDED_READ)
2846: channel_output_poll_extended_read(ssh, c);
1.25 markus 2847: }
1.1 deraadt 2848: }
2849:
1.354 markus 2850: /* -- mux proxy support */
2851:
2852: /*
2853: * When multiplexing channel messages for mux clients we have to deal
2854: * with downstream messages from the mux client and upstream messages
2855: * from the ssh server:
2856: * 1) Handling downstream messages is straightforward and happens
2857: * in channel_proxy_downstream():
2858: * - We forward all messages (mostly) unmodified to the server.
2859: * - However, in order to route messages from upstream to the correct
2860: * downstream client, we have to replace the channel IDs used by the
2861: * mux clients with a unique channel ID because the mux clients might
2862: * use conflicting channel IDs.
2863: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2864: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2865: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2866: * with the newly allocated channel ID.
2867: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 2868: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 2869: * is then translated back to the original mux client ID.
2870: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2871: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2872: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2873: * downstream mux client are removed.
2874: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2875: * requires more work, because they are not addressed to a specific
2876: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2877: * out whether the request is addressed to the local client or a
2878: * specific downstream client based on the listen-address/port.
1.380 djm 2879: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 2880: * not supported as the matching session/channel cannot be identified
2881: * easily.
2882: */
2883:
2884: /*
2885: * receive packets from downstream mux clients:
2886: * channel callback fired on read from mux client, creates
2887: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2888: * on channel creation.
2889: */
2890: int
1.367 djm 2891: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2892: {
2893: Channel *c = NULL;
2894: struct sshbuf *original = NULL, *modified = NULL;
2895: const u_char *cp;
2896: char *ctype = NULL, *listen_host = NULL;
2897: u_char type;
2898: size_t have;
1.370 djm 2899: int ret = -1, r;
1.355 djm 2900: u_int id, remote_id, listen_port;
1.354 markus 2901:
1.367 djm 2902: /* sshbuf_dump(downstream->input, stderr); */
2903: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2904: != 0) {
1.403 djm 2905: error_fr(r, "parse");
1.354 markus 2906: return -1;
2907: }
2908: if (have < 2) {
1.403 djm 2909: error_f("short message");
1.354 markus 2910: return -1;
2911: }
2912: type = cp[1];
2913: /* skip padlen + type */
2914: cp += 2;
2915: have -= 2;
2916: if (ssh_packet_log_type(type))
1.403 djm 2917: debug3_f("channel %u: down->up: type %u",
1.354 markus 2918: downstream->self, type);
2919:
2920: switch (type) {
2921: case SSH2_MSG_CHANNEL_OPEN:
2922: if ((original = sshbuf_from(cp, have)) == NULL ||
2923: (modified = sshbuf_new()) == NULL) {
1.403 djm 2924: error_f("alloc");
1.354 markus 2925: goto out;
2926: }
2927: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2928: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 2929: error_fr(r, "parse");
1.354 markus 2930: goto out;
2931: }
1.367 djm 2932: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 2933: -1, -1, -1, 0, 0, 0, ctype, 1);
1.354 markus 2934: c->mux_ctx = downstream; /* point to mux client */
2935: c->mux_downstream_id = id; /* original downstream id */
2936: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2937: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2938: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 2939: error_fr(r, "compose");
1.367 djm 2940: channel_free(ssh, c);
1.354 markus 2941: goto out;
2942: }
2943: break;
2944: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2945: /*
2946: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2947: * need to parse 'remote_id' instead of 'ctype'.
2948: */
2949: if ((original = sshbuf_from(cp, have)) == NULL ||
2950: (modified = sshbuf_new()) == NULL) {
1.403 djm 2951: error_f("alloc");
1.354 markus 2952: goto out;
2953: }
2954: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2955: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 2956: error_fr(r, "parse");
1.354 markus 2957: goto out;
2958: }
1.367 djm 2959: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 2960: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
1.354 markus 2961: c->mux_ctx = downstream; /* point to mux client */
2962: c->mux_downstream_id = id;
2963: c->remote_id = remote_id;
1.368 djm 2964: c->have_remote_id = 1;
1.354 markus 2965: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2966: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2967: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 2968: error_fr(r, "compose");
1.367 djm 2969: channel_free(ssh, c);
1.354 markus 2970: goto out;
2971: }
2972: break;
2973: case SSH2_MSG_GLOBAL_REQUEST:
2974: if ((original = sshbuf_from(cp, have)) == NULL) {
1.403 djm 2975: error_f("alloc");
1.354 markus 2976: goto out;
2977: }
2978: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
1.403 djm 2979: error_fr(r, "parse");
1.354 markus 2980: goto out;
2981: }
2982: if (strcmp(ctype, "tcpip-forward") != 0) {
1.403 djm 2983: error_f("unsupported request %s", ctype);
1.354 markus 2984: goto out;
2985: }
2986: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2987: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2988: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
1.403 djm 2989: error_fr(r, "parse");
1.354 markus 2990: goto out;
2991: }
1.355 djm 2992: if (listen_port > 65535) {
1.403 djm 2993: error_f("tcpip-forward for %s: bad port %u",
2994: listen_host, listen_port);
1.355 djm 2995: goto out;
2996: }
1.354 markus 2997: /* Record that connection to this host/port is permitted. */
1.381 djm 2998: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 2999: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 3000: listen_host = NULL;
3001: break;
3002: case SSH2_MSG_CHANNEL_CLOSE:
3003: if (have < 4)
3004: break;
3005: remote_id = PEEK_U32(cp);
1.367 djm 3006: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 3007: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 3008: channel_free(ssh, c);
1.354 markus 3009: else
3010: c->flags |= CHAN_CLOSE_SENT;
3011: }
3012: break;
3013: }
3014: if (modified) {
3015: if ((r = sshpkt_start(ssh, type)) != 0 ||
3016: (r = sshpkt_putb(ssh, modified)) != 0 ||
3017: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3018: error_fr(r, "send");
1.354 markus 3019: goto out;
3020: }
3021: } else {
3022: if ((r = sshpkt_start(ssh, type)) != 0 ||
3023: (r = sshpkt_put(ssh, cp, have)) != 0 ||
3024: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 3025: error_fr(r, "send");
1.354 markus 3026: goto out;
3027: }
3028: }
3029: ret = 0;
3030: out:
3031: free(ctype);
3032: free(listen_host);
3033: sshbuf_free(original);
3034: sshbuf_free(modified);
3035: return ret;
3036: }
3037:
3038: /*
3039: * receive packets from upstream server and de-multiplex packets
3040: * to correct downstream:
3041: * implemented as a helper for channel input handlers,
3042: * replaces local (proxy) channel ID with downstream channel ID.
3043: */
3044: int
1.363 markus 3045: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 3046: {
3047: struct sshbuf *b = NULL;
3048: Channel *downstream;
3049: const u_char *cp = NULL;
3050: size_t len;
3051: int r;
3052:
3053: /*
3054: * When receiving packets from the peer we need to check whether we
3055: * need to forward the packets to the mux client. In this case we
1.380 djm 3056: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 3057: * so we can cleanup the channel.
3058: */
3059: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
3060: return 0;
3061: if ((downstream = c->mux_ctx) == NULL)
3062: return 0;
3063: switch (type) {
3064: case SSH2_MSG_CHANNEL_CLOSE:
3065: case SSH2_MSG_CHANNEL_DATA:
3066: case SSH2_MSG_CHANNEL_EOF:
3067: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
3068: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3069: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
3070: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
3071: case SSH2_MSG_CHANNEL_SUCCESS:
3072: case SSH2_MSG_CHANNEL_FAILURE:
3073: case SSH2_MSG_CHANNEL_REQUEST:
3074: break;
3075: default:
1.403 djm 3076: debug2_f("channel %u: unsupported type %u", c->self, type);
1.354 markus 3077: return 0;
3078: }
3079: if ((b = sshbuf_new()) == NULL) {
1.403 djm 3080: error_f("alloc reply");
1.354 markus 3081: goto out;
3082: }
3083: /* get remaining payload (after id) */
3084: cp = sshpkt_ptr(ssh, &len);
3085: if (cp == NULL) {
1.403 djm 3086: error_f("no packet");
1.354 markus 3087: goto out;
3088: }
3089: /* translate id and send to muxclient */
3090: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
3091: (r = sshbuf_put_u8(b, type)) != 0 ||
3092: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
3093: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 3094: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.403 djm 3095: error_fr(r, "compose muxclient");
1.354 markus 3096: goto out;
3097: }
3098: /* sshbuf_dump(b, stderr); */
3099: if (ssh_packet_log_type(type))
1.403 djm 3100: debug3_f("channel %u: up->down: type %u", c->self, type);
1.354 markus 3101: out:
3102: /* update state */
3103: switch (type) {
3104: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3105: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 3106: if (cp && len > 4) {
1.354 markus 3107: c->remote_id = PEEK_U32(cp);
1.368 djm 3108: c->have_remote_id = 1;
3109: }
1.354 markus 3110: break;
3111: case SSH2_MSG_CHANNEL_CLOSE:
3112: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 3113: channel_free(ssh, c);
1.354 markus 3114: else
3115: c->flags |= CHAN_CLOSE_RCVD;
3116: break;
3117: }
3118: sshbuf_free(b);
3119: return 1;
3120: }
1.121 markus 3121:
3122: /* -- protocol input */
1.249 djm 3123:
1.367 djm 3124: /* Parse a channel ID from the current packet */
3125: static int
3126: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
3127: {
3128: u_int32_t id;
3129: int r;
3130:
3131: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
1.403 djm 3132: error_r(r, "%s: parse id", where);
1.367 djm 3133: ssh_packet_disconnect(ssh, "Invalid %s message", what);
3134: }
3135: if (id > INT_MAX) {
1.403 djm 3136: error_r(r, "%s: bad channel id %u", where, id);
1.367 djm 3137: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
3138: }
3139: return (int)id;
3140: }
3141:
3142: /* Lookup a channel from an ID in the current packet */
3143: static Channel *
3144: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
3145: {
3146: int id = channel_parse_id(ssh, where, what);
3147: Channel *c;
3148:
3149: if ((c = channel_lookup(ssh, id)) == NULL) {
3150: ssh_packet_disconnect(ssh,
3151: "%s packet referred to nonexistent channel %d", what, id);
3152: }
3153: return c;
3154: }
3155:
1.339 markus 3156: int
1.363 markus 3157: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3158: {
1.332 djm 3159: const u_char *data;
1.367 djm 3160: size_t data_len, win_len;
3161: Channel *c = channel_from_packet_id(ssh, __func__, "data");
3162: int r;
1.25 markus 3163:
1.363 markus 3164: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3165: return 0;
1.25 markus 3166:
3167: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 3168: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 3169: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
3170: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 3171: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 3172: return 0;
1.37 markus 3173:
1.25 markus 3174: /* Get the data. */
1.389 djm 3175: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3176: (r = sshpkt_get_end(ssh)) != 0)
1.403 djm 3177: fatal_fr(r, "channel %i: get data", c->self);
1.367 djm 3178:
1.309 djm 3179: win_len = data_len;
3180: if (c->datagram)
3181: win_len += 4; /* string length header */
1.200 markus 3182:
3183: /*
1.367 djm 3184: * The sending side reduces its window as it sends data, so we
3185: * must 'fake' consumption of the data in order to ensure that window
3186: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 3187: */
1.358 djm 3188: if (c->ostate != CHAN_OUTPUT_OPEN) {
3189: c->local_window -= win_len;
3190: c->local_consumed += win_len;
1.339 markus 3191: return 0;
1.200 markus 3192: }
1.41 markus 3193:
1.358 djm 3194: if (win_len > c->local_maxpacket) {
1.367 djm 3195: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 3196: c->self, win_len, c->local_maxpacket);
1.367 djm 3197: return 0;
1.358 djm 3198: }
3199: if (win_len > c->local_window) {
1.367 djm 3200: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 3201: c->self, win_len, c->local_window);
3202: return 0;
1.44 markus 3203: }
1.358 djm 3204: c->local_window -= win_len;
3205:
1.367 djm 3206: if (c->datagram) {
3207: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
1.403 djm 3208: fatal_fr(r, "channel %i: append datagram", c->self);
1.367 djm 3209: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
1.403 djm 3210: fatal_fr(r, "channel %i: append data", c->self);
1.367 djm 3211:
1.339 markus 3212: return 0;
1.1 deraadt 3213: }
1.121 markus 3214:
1.339 markus 3215: int
1.363 markus 3216: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 3217: {
1.367 djm 3218: const u_char *data;
3219: size_t data_len;
3220: u_int32_t tcode;
3221: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
3222: int r;
1.44 markus 3223:
1.363 markus 3224: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3225: return 0;
1.44 markus 3226: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 3227: logit("channel %d: ext data for non open", c->self);
1.339 markus 3228: return 0;
1.172 markus 3229: }
3230: if (c->flags & CHAN_EOF_RCVD) {
1.404 djm 3231: if (ssh->compat & SSH_BUG_EXTEOF)
1.367 djm 3232: debug("channel %d: accepting ext data after eof",
3233: c->self);
1.172 markus 3234: else
1.367 djm 3235: ssh_packet_disconnect(ssh, "Received extended_data "
3236: "after EOF on channel %d.", c->self);
3237: }
3238:
3239: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
1.403 djm 3240: error_fr(r, "parse tcode");
1.367 djm 3241: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3242: }
3243: if (c->efd == -1 ||
3244: c->extended_usage != CHAN_EXTENDED_WRITE ||
3245: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3246: logit("channel %d: bad ext data", c->self);
1.339 markus 3247: return 0;
1.44 markus 3248: }
1.389 djm 3249: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3250: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3251: error_fr(r, "parse data");
1.367 djm 3252: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3253: }
3254:
1.44 markus 3255: if (data_len > c->local_window) {
1.367 djm 3256: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3257: c->self, data_len, c->local_window);
1.339 markus 3258: return 0;
1.44 markus 3259: }
1.367 djm 3260: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3261: /* XXX sshpkt_getb? */
3262: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
1.403 djm 3263: error_fr(r, "append");
1.44 markus 3264: c->local_window -= data_len;
1.339 markus 3265: return 0;
1.44 markus 3266: }
3267:
1.339 markus 3268: int
1.363 markus 3269: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3270: {
1.367 djm 3271: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3272: int r;
1.367 djm 3273:
1.389 djm 3274: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3275: error_fr(r, "parse data");
1.389 djm 3276: ssh_packet_disconnect(ssh, "Invalid ieof message");
3277: }
1.41 markus 3278:
1.363 markus 3279: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3280: return 0;
1.367 djm 3281: chan_rcvd_ieof(ssh, c);
1.133 markus 3282:
3283: /* XXX force input close */
1.156 markus 3284: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3285: debug("channel %d: FORCE input drain", c->self);
3286: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3287: if (sshbuf_len(c->input) == 0)
3288: chan_ibuf_empty(ssh, c);
1.133 markus 3289: }
1.339 markus 3290: return 0;
1.41 markus 3291: }
1.1 deraadt 3292:
1.339 markus 3293: int
1.363 markus 3294: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3295: {
1.367 djm 3296: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3297: int r;
1.151 markus 3298:
1.363 markus 3299: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3300: return 0;
1.389 djm 3301: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3302: error_fr(r, "parse data");
1.389 djm 3303: ssh_packet_disconnect(ssh, "Invalid oclose message");
3304: }
1.367 djm 3305: chan_rcvd_oclose(ssh, c);
1.339 markus 3306: return 0;
1.1 deraadt 3307: }
3308:
1.339 markus 3309: int
1.363 markus 3310: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3311: {
1.367 djm 3312: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3313: u_int32_t remote_window, remote_maxpacket;
3314: int r;
1.25 markus 3315:
1.363 markus 3316: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3317: return 0;
3318: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3319: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3320: "non-opening channel %d.", c->self);
3321: /*
3322: * Record the remote channel number and mark that the channel
3323: * is now open.
3324: */
1.368 djm 3325: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3326: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3327: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3328: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3329: error_fr(r, "window/maxpacket");
1.389 djm 3330: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3331: }
3332:
1.368 djm 3333: c->have_remote_id = 1;
1.367 djm 3334: c->remote_window = remote_window;
3335: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3336: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3337: if (c->open_confirm) {
1.403 djm 3338: debug2_f("channel %d: callback start", c->self);
1.367 djm 3339: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
1.403 djm 3340: debug2_f("channel %d: callback done", c->self);
1.44 markus 3341: }
1.358 djm 3342: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3343: c->remote_window, c->remote_maxpacket);
1.339 markus 3344: return 0;
1.1 deraadt 3345: }
3346:
1.127 itojun 3347: static char *
1.114 markus 3348: reason2txt(int reason)
3349: {
1.143 deraadt 3350: switch (reason) {
1.114 markus 3351: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3352: return "administratively prohibited";
3353: case SSH2_OPEN_CONNECT_FAILED:
3354: return "connect failed";
3355: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3356: return "unknown channel type";
3357: case SSH2_OPEN_RESOURCE_SHORTAGE:
3358: return "resource shortage";
3359: }
1.117 stevesk 3360: return "unknown reason";
1.114 markus 3361: }
3362:
1.339 markus 3363: int
1.363 markus 3364: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3365: {
1.367 djm 3366: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3367: u_int32_t reason;
3368: char *msg = NULL;
3369: int r;
1.25 markus 3370:
1.363 markus 3371: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3372: return 0;
3373: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3374: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3375: "non-opening channel %d.", c->self);
3376: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
1.403 djm 3377: error_fr(r, "parse reason");
1.389 djm 3378: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3379: }
1.378 djm 3380: /* skip language */
3381: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3382: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3383: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3384: error_fr(r, "parse msg/lang");
1.389 djm 3385: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3386: }
1.367 djm 3387: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3388: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3389: free(msg);
3390: if (c->open_confirm) {
1.403 djm 3391: debug2_f("channel %d: callback start", c->self);
1.367 djm 3392: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
1.403 djm 3393: debug2_f("channel %d: callback done", c->self);
1.44 markus 3394: }
1.291 djm 3395: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3396: chan_mark_dead(ssh, c);
1.339 markus 3397: return 0;
1.44 markus 3398: }
3399:
1.339 markus 3400: int
1.363 markus 3401: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3402: {
1.367 djm 3403: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3404: Channel *c;
1.367 djm 3405: u_int32_t adjust;
3406: u_int new_rwin;
3407: int r;
1.1 deraadt 3408:
1.367 djm 3409: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3410: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3411: return 0;
1.372 markus 3412: }
1.367 djm 3413:
1.363 markus 3414: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3415: return 0;
1.389 djm 3416: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3417: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3418: error_fr(r, "parse adjust");
1.389 djm 3419: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3420: }
3421: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3422: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3423: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3424: c->self, adjust, c->remote_window);
3425: }
3426: c->remote_window = new_rwin;
1.339 markus 3427: return 0;
1.121 markus 3428: }
1.1 deraadt 3429:
1.339 markus 3430: int
1.363 markus 3431: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3432: {
1.367 djm 3433: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3434: Channel *c;
3435: struct channel_confirm *cc;
3436:
3437: /* Reset keepalive timeout */
1.389 djm 3438: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3439:
1.403 djm 3440: debug2_f("type %d id %d", type, id);
1.275 djm 3441:
1.367 djm 3442: if ((c = channel_lookup(ssh, id)) == NULL) {
1.403 djm 3443: logit_f("%d: unknown", id);
1.339 markus 3444: return 0;
1.367 djm 3445: }
1.363 markus 3446: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3447: return 0;
1.394 dtucker 3448: if (sshpkt_get_end(ssh) != 0)
1.389 djm 3449: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3450: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3451: return 0;
1.367 djm 3452: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3453: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 3454: freezero(cc, sizeof(*cc));
1.339 markus 3455: return 0;
1.275 djm 3456: }
1.121 markus 3457:
3458: /* -- tcp forwarding */
1.135 markus 3459:
3460: void
1.367 djm 3461: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3462: {
1.367 djm 3463: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3464: }
1.121 markus 3465:
1.312 djm 3466:
3467: /*
3468: * Determine whether or not a port forward listens to loopback, the
3469: * specified address or wildcard. On the client, a specified bind
3470: * address will always override gateway_ports. On the server, a
3471: * gateway_ports of 1 (``yes'') will override the client's specification
3472: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3473: * will bind to whatever address the client asked for.
3474: *
3475: * Special-case listen_addrs are:
3476: *
3477: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3478: * "" (empty string), "*" -> wildcard v4/v6
3479: * "localhost" -> loopback v4/v6
1.334 djm 3480: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3481: */
3482: static const char *
1.389 djm 3483: channel_fwd_bind_addr(struct ssh *ssh, const char *listen_addr, int *wildcardp,
1.336 millert 3484: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3485: {
3486: const char *addr = NULL;
3487: int wildcard = 0;
3488:
3489: if (listen_addr == NULL) {
3490: /* No address specified: default to gateway_ports setting */
1.336 millert 3491: if (fwd_opts->gateway_ports)
1.312 djm 3492: wildcard = 1;
1.336 millert 3493: } else if (fwd_opts->gateway_ports || is_client) {
1.404 djm 3494: if (((ssh->compat & SSH_OLD_FORWARD_ADDR) &&
1.312 djm 3495: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3496: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3497: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3498: wildcard = 1;
1.326 djm 3499: /*
3500: * Notify client if they requested a specific listen
3501: * address and it was overridden.
3502: */
3503: if (*listen_addr != '\0' &&
3504: strcmp(listen_addr, "0.0.0.0") != 0 &&
3505: strcmp(listen_addr, "*") != 0) {
1.389 djm 3506: ssh_packet_send_debug(ssh,
3507: "Forwarding listen address "
1.326 djm 3508: "\"%s\" overridden by server "
3509: "GatewayPorts", listen_addr);
3510: }
1.334 djm 3511: } else if (strcmp(listen_addr, "localhost") != 0 ||
3512: strcmp(listen_addr, "127.0.0.1") == 0 ||
3513: strcmp(listen_addr, "::1") == 0) {
1.395 djm 3514: /*
3515: * Accept explicit localhost address when
3516: * GatewayPorts=yes. The "localhost" hostname is
3517: * deliberately skipped here so it will listen on all
3518: * available local address families.
3519: */
1.334 djm 3520: addr = listen_addr;
1.326 djm 3521: }
1.334 djm 3522: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3523: strcmp(listen_addr, "::1") == 0) {
3524: /*
3525: * If a specific IPv4/IPv6 localhost address has been
3526: * requested then accept it even if gateway_ports is in
3527: * effect. This allows the client to prefer IPv4 or IPv6.
3528: */
3529: addr = listen_addr;
1.312 djm 3530: }
3531: if (wildcardp != NULL)
3532: *wildcardp = wildcard;
3533: return addr;
3534: }
3535:
1.160 markus 3536: static int
1.367 djm 3537: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3538: struct Forward *fwd, int *allocated_listen_port,
3539: struct ForwardOptions *fwd_opts)
1.25 markus 3540: {
1.113 markus 3541: Channel *c;
1.226 djm 3542: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3543: struct addrinfo hints, *ai, *aitop;
1.212 djm 3544: const char *host, *addr;
1.35 markus 3545: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3546: in_port_t *lport_p;
1.25 markus 3547:
1.212 djm 3548: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3549:
1.344 millert 3550: if (is_client && fwd->connect_path != NULL) {
3551: host = fwd->connect_path;
3552: } else {
3553: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3554: fwd->listen_host : fwd->connect_host;
3555: if (host == NULL) {
3556: error("No forward host name.");
3557: return 0;
3558: }
3559: if (strlen(host) >= NI_MAXHOST) {
3560: error("Forward host name too long.");
3561: return 0;
3562: }
1.87 markus 3563: }
1.25 markus 3564:
1.312 djm 3565: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3566: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3567: is_client, fwd_opts);
1.403 djm 3568: debug3_f("type %d wildcard %d addr %s", type, wildcard,
3569: (addr == NULL) ? "NULL" : addr);
1.212 djm 3570:
3571: /*
1.35 markus 3572: * getaddrinfo returns a loopback address if the hostname is
3573: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3574: */
1.35 markus 3575: memset(&hints, 0, sizeof(hints));
1.367 djm 3576: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3577: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3578: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3579: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3580: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3581: if (addr == NULL) {
3582: /* This really shouldn't happen */
1.389 djm 3583: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3584: ssh_gai_strerror(r));
1.212 djm 3585: } else {
1.403 djm 3586: error_f("getaddrinfo(%.64s): %s", addr,
1.271 dtucker 3587: ssh_gai_strerror(r));
1.212 djm 3588: }
1.218 markus 3589: return 0;
1.212 djm 3590: }
1.295 djm 3591: if (allocated_listen_port != NULL)
3592: *allocated_listen_port = 0;
1.35 markus 3593: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3594: switch (ai->ai_family) {
3595: case AF_INET:
3596: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3597: sin_port;
3598: break;
3599: case AF_INET6:
3600: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3601: sin6_port;
3602: break;
3603: default:
1.35 markus 3604: continue;
1.295 djm 3605: }
3606: /*
3607: * If allocating a port for -R forwards, then use the
3608: * same port for all address families.
3609: */
1.367 djm 3610: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3611: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3612: *allocated_listen_port > 0)
1.295 djm 3613: *lport_p = htons(*allocated_listen_port);
3614:
1.35 markus 3615: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3616: strport, sizeof(strport),
3617: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.403 djm 3618: error_f("getnameinfo failed");
1.35 markus 3619: continue;
3620: }
3621: /* Create a port to listen for the host. */
1.300 dtucker 3622: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 3623: if (sock == -1) {
1.35 markus 3624: /* this is no error since kernel may not support ipv6 */
1.377 djm 3625: verbose("socket [%s]:%s: %.100s", ntop, strport,
3626: strerror(errno));
1.35 markus 3627: continue;
3628: }
1.226 djm 3629:
1.376 djm 3630: set_reuseaddr(sock);
1.182 stevesk 3631:
1.295 djm 3632: debug("Local forwarding listening on %s port %s.",
3633: ntop, strport);
1.35 markus 3634:
3635: /* Bind the socket to the address. */
1.393 deraadt 3636: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3637: /*
3638: * address can be in if use ipv6 address is
3639: * already bound
3640: */
1.377 djm 3641: verbose("bind [%s]:%s: %.100s",
3642: ntop, strport, strerror(errno));
1.35 markus 3643: close(sock);
3644: continue;
3645: }
3646: /* Start listening for connections on the socket. */
1.393 deraadt 3647: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3648: error("listen [%s]:%s: %.100s", ntop, strport,
3649: strerror(errno));
1.35 markus 3650: close(sock);
3651: continue;
3652: }
1.295 djm 3653:
3654: /*
1.336 millert 3655: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3656: * record what we got.
3657: */
1.367 djm 3658: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3659: fwd->listen_port == 0 &&
1.295 djm 3660: allocated_listen_port != NULL &&
3661: *allocated_listen_port == 0) {
1.350 djm 3662: *allocated_listen_port = get_local_port(sock);
1.295 djm 3663: debug("Allocated listen port %d",
3664: *allocated_listen_port);
3665: }
3666:
1.35 markus 3667: /* Allocate a channel number for the socket. */
1.367 djm 3668: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3669: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3670: 0, "port listener", 1);
1.293 djm 3671: c->path = xstrdup(host);
1.336 millert 3672: c->host_port = fwd->connect_port;
1.312 djm 3673: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3674: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.404 djm 3675: !(ssh->compat & SSH_BUG_DYNAMIC_RPORT))
1.315 markus 3676: c->listening_port = *allocated_listen_port;
3677: else
1.336 millert 3678: c->listening_port = fwd->listen_port;
1.35 markus 3679: success = 1;
3680: }
3681: if (success == 0)
1.403 djm 3682: error_f("cannot listen to port: %d", fwd->listen_port);
1.35 markus 3683: freeaddrinfo(aitop);
1.87 markus 3684: return success;
1.25 markus 3685: }
1.1 deraadt 3686:
1.336 millert 3687: static int
1.367 djm 3688: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3689: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3690: {
3691: struct sockaddr_un sunaddr;
3692: const char *path;
3693: Channel *c;
3694: int port, sock;
3695: mode_t omask;
3696:
3697: switch (type) {
3698: case SSH_CHANNEL_UNIX_LISTENER:
3699: if (fwd->connect_path != NULL) {
3700: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3701: error("Local connecting path too long: %s",
3702: fwd->connect_path);
3703: return 0;
3704: }
3705: path = fwd->connect_path;
3706: port = PORT_STREAMLOCAL;
3707: } else {
3708: if (fwd->connect_host == NULL) {
3709: error("No forward host name.");
3710: return 0;
3711: }
3712: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3713: error("Forward host name too long.");
3714: return 0;
3715: }
3716: path = fwd->connect_host;
3717: port = fwd->connect_port;
3718: }
3719: break;
3720: case SSH_CHANNEL_RUNIX_LISTENER:
3721: path = fwd->listen_path;
3722: port = PORT_STREAMLOCAL;
3723: break;
3724: default:
1.403 djm 3725: error_f("unexpected channel type %d", type);
1.336 millert 3726: return 0;
3727: }
3728:
3729: if (fwd->listen_path == NULL) {
3730: error("No forward path name.");
3731: return 0;
3732: }
3733: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3734: error("Local listening path too long: %s", fwd->listen_path);
3735: return 0;
3736: }
3737:
1.403 djm 3738: debug3_f("type %d path %s", type, fwd->listen_path);
1.336 millert 3739:
3740: /* Start a Unix domain listener. */
3741: omask = umask(fwd_opts->streamlocal_bind_mask);
3742: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3743: fwd_opts->streamlocal_bind_unlink);
3744: umask(omask);
3745: if (sock < 0)
3746: return 0;
3747:
3748: debug("Local forwarding listening on path %s.", fwd->listen_path);
3749:
3750: /* Allocate a channel number for the socket. */
1.367 djm 3751: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3752: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3753: 0, "unix listener", 1);
3754: c->path = xstrdup(path);
3755: c->host_port = port;
3756: c->listening_port = PORT_STREAMLOCAL;
3757: c->listening_addr = xstrdup(fwd->listen_path);
3758: return 1;
3759: }
3760:
3761: static int
1.367 djm 3762: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3763: const char *host, u_short port)
1.202 djm 3764: {
1.209 avsm 3765: u_int i;
3766: int found = 0;
1.202 djm 3767:
1.367 djm 3768: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3769: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3770: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3771: continue;
3772: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
1.403 djm 3773: debug2_f("close channel %d", i);
1.367 djm 3774: channel_free(ssh, c);
1.312 djm 3775: found = 1;
3776: }
3777: }
3778:
1.367 djm 3779: return found;
1.312 djm 3780: }
3781:
1.336 millert 3782: static int
1.367 djm 3783: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3784: {
3785: u_int i;
3786: int found = 0;
3787:
1.367 djm 3788: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3789: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3790: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3791: continue;
3792: if (c->path == NULL)
3793: continue;
3794: if (strcmp(c->path, path) == 0) {
1.403 djm 3795: debug2_f("close channel %d", i);
1.367 djm 3796: channel_free(ssh, c);
1.336 millert 3797: found = 1;
3798: }
3799: }
3800:
1.367 djm 3801: return found;
1.336 millert 3802: }
3803:
1.312 djm 3804: int
1.367 djm 3805: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3806: {
1.367 djm 3807: if (fwd->listen_path != NULL) {
3808: return channel_cancel_rport_listener_streamlocal(ssh,
3809: fwd->listen_path);
3810: } else {
3811: return channel_cancel_rport_listener_tcpip(ssh,
3812: fwd->listen_host, fwd->listen_port);
3813: }
1.336 millert 3814: }
3815:
3816: static int
1.367 djm 3817: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3818: const char *lhost, u_short lport, int cport,
3819: struct ForwardOptions *fwd_opts)
1.312 djm 3820: {
3821: u_int i;
3822: int found = 0;
1.389 djm 3823: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 3824:
1.367 djm 3825: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3826: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3827: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3828: continue;
1.313 markus 3829: if (c->listening_port != lport)
1.312 djm 3830: continue;
1.313 markus 3831: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3832: /* skip dynamic forwardings */
3833: if (c->host_port == 0)
3834: continue;
3835: } else {
3836: if (c->host_port != cport)
3837: continue;
3838: }
1.312 djm 3839: if ((c->listening_addr == NULL && addr != NULL) ||
3840: (c->listening_addr != NULL && addr == NULL))
3841: continue;
3842: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.403 djm 3843: debug2_f("close channel %d", i);
1.367 djm 3844: channel_free(ssh, c);
1.202 djm 3845: found = 1;
3846: }
3847: }
3848:
1.367 djm 3849: return found;
1.202 djm 3850: }
3851:
1.336 millert 3852: static int
1.367 djm 3853: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3854: {
3855: u_int i;
3856: int found = 0;
3857:
3858: if (path == NULL) {
1.403 djm 3859: error_f("no path specified.");
1.336 millert 3860: return 0;
3861: }
3862:
1.367 djm 3863: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3864: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3865: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3866: continue;
3867: if (c->listening_addr == NULL)
3868: continue;
3869: if (strcmp(c->listening_addr, path) == 0) {
1.403 djm 3870: debug2_f("close channel %d", i);
1.367 djm 3871: channel_free(ssh, c);
1.336 millert 3872: found = 1;
3873: }
3874: }
3875:
1.367 djm 3876: return found;
1.336 millert 3877: }
3878:
3879: int
1.367 djm 3880: channel_cancel_lport_listener(struct ssh *ssh,
3881: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3882: {
1.367 djm 3883: if (fwd->listen_path != NULL) {
3884: return channel_cancel_lport_listener_streamlocal(ssh,
3885: fwd->listen_path);
3886: } else {
3887: return channel_cancel_lport_listener_tcpip(ssh,
3888: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3889: }
1.336 millert 3890: }
3891:
1.362 markus 3892: /* protocol local port fwd, used by ssh */
1.160 markus 3893: int
1.367 djm 3894: channel_setup_local_fwd_listener(struct ssh *ssh,
3895: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3896: {
1.336 millert 3897: if (fwd->listen_path != NULL) {
1.367 djm 3898: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3899: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3900: } else {
1.367 djm 3901: return channel_setup_fwd_listener_tcpip(ssh,
3902: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3903: }
1.160 markus 3904: }
3905:
1.381 djm 3906: /* Matches a remote forwarding permission against a requested forwarding */
3907: static int
3908: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
3909: {
3910: int ret;
3911: char *lhost;
3912:
3913: /* XXX add ACLs for streamlocal */
3914: if (fwd->listen_path != NULL)
3915: return 1;
3916:
3917: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
3918: return 0;
3919:
3920: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
3921: allowed_open->listen_port != fwd->listen_port)
3922: return 0;
3923:
3924: /* Match hostnames case-insensitively */
3925: lhost = xstrdup(fwd->listen_host);
3926: lowercase(lhost);
3927: ret = match_pattern(lhost, allowed_open->listen_host);
3928: free(lhost);
3929:
3930: return ret;
3931: }
3932:
3933: /* Checks whether a requested remote forwarding is permitted */
3934: static int
3935: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
3936: {
3937: struct ssh_channels *sc = ssh->chanctxt;
3938: struct permission_set *pset = &sc->remote_perms;
3939: u_int i, permit, permit_adm = 1;
3940: struct permission *perm;
3941:
3942: /* XXX apply GatewayPorts override before checking? */
3943:
3944: permit = pset->all_permitted;
3945: if (!permit) {
3946: for (i = 0; i < pset->num_permitted_user; i++) {
3947: perm = &pset->permitted_user[i];
3948: if (remote_open_match(perm, fwd)) {
3949: permit = 1;
3950: break;
3951: }
3952: }
3953: }
3954:
3955: if (pset->num_permitted_admin > 0) {
3956: permit_adm = 0;
3957: for (i = 0; i < pset->num_permitted_admin; i++) {
3958: perm = &pset->permitted_admin[i];
3959: if (remote_open_match(perm, fwd)) {
3960: permit_adm = 1;
3961: break;
3962: }
3963: }
3964: }
3965:
3966: return permit && permit_adm;
3967: }
3968:
1.160 markus 3969: /* protocol v2 remote port fwd, used by sshd */
3970: int
1.367 djm 3971: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3972: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3973: {
1.381 djm 3974: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 3975: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 3976: if (fwd->listen_path != NULL)
3977: /* XXX always allowed, see remote_open_match() */
3978: logit("Received request from %.100s port %d to "
3979: "remote forward to path \"%.100s\", "
3980: "but the request was denied.",
3981: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3982: fwd->listen_path);
3983: else if(fwd->listen_host != NULL)
3984: logit("Received request from %.100s port %d to "
3985: "remote forward to host %.100s port %d, "
3986: "but the request was denied.",
3987: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3988: fwd->listen_host, fwd->listen_port );
3989: else
3990: logit("Received request from %.100s port %d to remote "
3991: "forward, but the request was denied.",
3992: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 3993: return 0;
3994: }
1.336 millert 3995: if (fwd->listen_path != NULL) {
1.367 djm 3996: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3997: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3998: } else {
1.367 djm 3999: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 4000: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
4001: fwd_opts);
4002: }
1.160 markus 4003: }
4004:
1.27 markus 4005: /*
1.312 djm 4006: * Translate the requested rfwd listen host to something usable for
4007: * this server.
4008: */
4009: static const char *
4010: channel_rfwd_bind_host(const char *listen_host)
4011: {
4012: if (listen_host == NULL) {
1.378 djm 4013: return "localhost";
1.312 djm 4014: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 4015: return "";
1.312 djm 4016: } else
4017: return listen_host;
4018: }
4019:
4020: /*
1.27 markus 4021: * Initiate forwarding of connections to port "port" on remote host through
4022: * the secure channel to host:port from local side.
1.315 markus 4023: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 4024: * channel_update_permission().
1.27 markus 4025: */
1.253 markus 4026: int
1.367 djm 4027: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 4028: {
1.367 djm 4029: int r, success = 0, idx = -1;
4030: char *host_to_connect, *listen_host, *listen_path;
4031: int port_to_connect, listen_port;
1.73 markus 4032:
1.25 markus 4033: /* Send the forward request to the remote side. */
1.358 djm 4034: if (fwd->listen_path != NULL) {
1.367 djm 4035: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4036: (r = sshpkt_put_cstring(ssh,
4037: "streamlocal-forward@openssh.com")) != 0 ||
4038: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4039: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
4040: (r = sshpkt_send(ssh)) != 0 ||
4041: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4042: fatal_fr(r, "request streamlocal");
1.336 millert 4043: } else {
1.367 djm 4044: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4045: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
4046: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4047: (r = sshpkt_put_cstring(ssh,
4048: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
4049: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
4050: (r = sshpkt_send(ssh)) != 0 ||
4051: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4052: fatal_fr(r, "request tcpip-forward");
1.73 markus 4053: }
1.358 djm 4054: /* Assume that server accepts the request */
4055: success = 1;
1.73 markus 4056: if (success) {
1.305 djm 4057: /* Record that connection to this host/port is permitted. */
1.367 djm 4058: host_to_connect = listen_host = listen_path = NULL;
4059: port_to_connect = listen_port = 0;
1.336 millert 4060: if (fwd->connect_path != NULL) {
1.367 djm 4061: host_to_connect = xstrdup(fwd->connect_path);
4062: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 4063: } else {
1.367 djm 4064: host_to_connect = xstrdup(fwd->connect_host);
4065: port_to_connect = fwd->connect_port;
1.336 millert 4066: }
4067: if (fwd->listen_path != NULL) {
1.367 djm 4068: listen_path = xstrdup(fwd->listen_path);
4069: listen_port = PORT_STREAMLOCAL;
1.336 millert 4070: } else {
1.367 djm 4071: if (fwd->listen_host != NULL)
4072: listen_host = xstrdup(fwd->listen_host);
4073: listen_port = fwd->listen_port;
4074: }
1.381 djm 4075: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 4076: host_to_connect, port_to_connect,
4077: listen_host, listen_path, listen_port, NULL);
1.44 markus 4078: }
1.367 djm 4079: return idx;
1.1 deraadt 4080: }
4081:
1.333 markus 4082: static int
1.381 djm 4083: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 4084: int requestedport)
1.333 markus 4085: {
4086: if (allowed_open->host_to_connect == NULL)
4087: return 0;
4088: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
4089: allowed_open->port_to_connect != requestedport)
4090: return 0;
1.351 dtucker 4091: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
4092: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 4093: return 0;
4094: return 1;
4095: }
4096:
4097: /*
1.336 millert 4098: * Note that in the listen host/port case
1.333 markus 4099: * we don't support FWD_PERMIT_ANY_PORT and
4100: * need to translate between the configured-host (listen_host)
4101: * and what we've sent to the remote server (channel_rfwd_bind_host)
4102: */
4103: static int
1.381 djm 4104: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 4105: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 4106: {
4107: const char *allowed_host;
4108:
4109: if (allowed_open->host_to_connect == NULL)
4110: return 0;
4111: if (allowed_open->listen_port != requestedport)
4112: return 0;
1.335 djm 4113: if (!translate && allowed_open->listen_host == NULL &&
4114: requestedhost == NULL)
4115: return 1;
1.333 markus 4116: allowed_host = translate ?
4117: channel_rfwd_bind_host(allowed_open->listen_host) :
4118: allowed_open->listen_host;
1.382 djm 4119: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 4120: strcmp(allowed_host, requestedhost) != 0)
4121: return 0;
4122: return 1;
4123: }
4124:
1.336 millert 4125: static int
1.381 djm 4126: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 4127: const char *requestedpath)
4128: {
4129: if (allowed_open->host_to_connect == NULL)
4130: return 0;
4131: if (allowed_open->listen_port != PORT_STREAMLOCAL)
4132: return 0;
4133: if (allowed_open->listen_path == NULL ||
4134: strcmp(allowed_open->listen_path, requestedpath) != 0)
4135: return 0;
4136: return 1;
4137: }
4138:
1.27 markus 4139: /*
1.208 deraadt 4140: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 4141: * local side.
4142: */
1.336 millert 4143: static int
1.367 djm 4144: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
4145: const char *host, u_short port)
1.202 djm 4146: {
1.367 djm 4147: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4148: struct permission_set *pset = &sc->local_perms;
1.367 djm 4149: int r;
4150: u_int i;
1.397 markus 4151: struct permission *perm = NULL;
1.202 djm 4152:
1.381 djm 4153: for (i = 0; i < pset->num_permitted_user; i++) {
4154: perm = &pset->permitted_user[i];
4155: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 4156: break;
1.381 djm 4157: perm = NULL;
1.202 djm 4158: }
1.381 djm 4159: if (perm == NULL) {
1.403 djm 4160: debug_f("requested forward not found");
1.312 djm 4161: return -1;
1.202 djm 4162: }
1.367 djm 4163: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4164: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
4165: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4166: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
4167: (r = sshpkt_put_u32(ssh, port)) != 0 ||
4168: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4169: fatal_fr(r, "send cancel");
1.367 djm 4170:
1.381 djm 4171: fwd_perm_clear(perm); /* unregister */
1.336 millert 4172:
4173: return 0;
4174: }
4175:
4176: /*
4177: * Request cancellation of remote forwarding of Unix domain socket
4178: * path from local side.
4179: */
4180: static int
1.367 djm 4181: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 4182: {
1.367 djm 4183: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4184: struct permission_set *pset = &sc->local_perms;
1.367 djm 4185: int r;
4186: u_int i;
1.397 markus 4187: struct permission *perm = NULL;
1.336 millert 4188:
1.381 djm 4189: for (i = 0; i < pset->num_permitted_user; i++) {
4190: perm = &pset->permitted_user[i];
4191: if (open_listen_match_streamlocal(perm, path))
1.336 millert 4192: break;
1.381 djm 4193: perm = NULL;
1.336 millert 4194: }
1.381 djm 4195: if (perm == NULL) {
1.403 djm 4196: debug_f("requested forward not found");
1.336 millert 4197: return -1;
4198: }
1.367 djm 4199: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4200: (r = sshpkt_put_cstring(ssh,
4201: "cancel-streamlocal-forward@openssh.com")) != 0 ||
4202: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4203: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
4204: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4205: fatal_fr(r, "send cancel");
1.367 djm 4206:
1.381 djm 4207: fwd_perm_clear(perm); /* unregister */
1.312 djm 4208:
4209: return 0;
1.202 djm 4210: }
4211:
4212: /*
1.336 millert 4213: * Request cancellation of remote forwarding of a connection from local side.
4214: */
4215: int
1.367 djm 4216: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 4217: {
4218: if (fwd->listen_path != NULL) {
1.367 djm 4219: return channel_request_rforward_cancel_streamlocal(ssh,
4220: fwd->listen_path);
1.336 millert 4221: } else {
1.367 djm 4222: return channel_request_rforward_cancel_tcpip(ssh,
4223: fwd->listen_host,
4224: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 4225: }
1.1 deraadt 4226: }
4227:
1.99 markus 4228: /*
1.381 djm 4229: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 4230: * usually called by the server, because the user could connect to any port
4231: * anyway, and the server has no way to know but to trust the client anyway.
4232: */
4233: void
1.381 djm 4234: channel_permit_all(struct ssh *ssh, int where)
4235: {
4236: struct permission_set *pset = permission_set_get(ssh, where);
4237:
4238: if (pset->num_permitted_user == 0)
4239: pset->all_permitted = 1;
4240: }
4241:
4242: /*
4243: * Permit the specified host/port for forwarding.
4244: */
4245: void
4246: channel_add_permission(struct ssh *ssh, int who, int where,
4247: char *host, int port)
4248: {
4249: int local = where == FORWARD_LOCAL;
4250: struct permission_set *pset = permission_set_get(ssh, where);
4251:
4252: debug("allow %s forwarding to host %s port %d",
4253: fwd_ident(who, where), host, port);
4254: /*
4255: * Remote forwards set listen_host/port, local forwards set
4256: * host/port_to_connect.
4257: */
4258: permission_set_add(ssh, who, where,
4259: local ? host : 0, local ? port : 0,
4260: local ? NULL : host, NULL, local ? 0 : port, NULL);
4261: pset->all_permitted = 0;
4262: }
4263:
4264: /*
4265: * Administratively disable forwarding.
4266: */
4267: void
4268: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4269: {
1.381 djm 4270: channel_clear_permission(ssh, FORWARD_ADM, where);
4271: permission_set_add(ssh, FORWARD_ADM, where,
4272: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4273: }
4274:
1.381 djm 4275: /*
4276: * Clear a list of permitted opens.
4277: */
1.101 markus 4278: void
1.381 djm 4279: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4280: {
1.381 djm 4281: struct permission **permp;
4282: u_int *npermp;
1.367 djm 4283:
1.381 djm 4284: permission_set_get_array(ssh, who, where, &permp, &npermp);
4285: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4286: *npermp = 0;
1.315 markus 4287: }
4288:
4289: /*
4290: * Update the listen port for a dynamic remote forward, after
4291: * the actual 'newport' has been allocated. If 'newport' < 0 is
4292: * passed then they entry will be invalidated.
4293: */
4294: void
1.381 djm 4295: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4296: {
1.381 djm 4297: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4298:
1.381 djm 4299: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
1.403 djm 4300: debug_f("index out of range: %d num_permitted_user %d",
4301: idx, pset->num_permitted_user);
1.315 markus 4302: return;
4303: }
4304: debug("%s allowed port %d for forwarding to host %s port %d",
4305: newport > 0 ? "Updating" : "Removing",
4306: newport,
1.381 djm 4307: pset->permitted_user[idx].host_to_connect,
4308: pset->permitted_user[idx].port_to_connect);
1.367 djm 4309: if (newport <= 0)
1.381 djm 4310: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4311: else {
1.381 djm 4312: pset->permitted_user[idx].listen_port =
1.404 djm 4313: (ssh->compat & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
1.315 markus 4314: }
1.99 markus 4315: }
4316:
1.314 dtucker 4317: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4318: int
4319: permitopen_port(const char *p)
4320: {
4321: int port;
4322:
4323: if (strcmp(p, "*") == 0)
4324: return FWD_PERMIT_ANY_PORT;
4325: if ((port = a2port(p)) > 0)
4326: return port;
4327: return -1;
4328: }
4329:
1.276 djm 4330: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4331: static int
1.276 djm 4332: connect_next(struct channel_connect *cctx)
1.41 markus 4333: {
1.276 djm 4334: int sock, saved_errno;
1.336 millert 4335: struct sockaddr_un *sunaddr;
1.367 djm 4336: char ntop[NI_MAXHOST];
4337: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4338:
1.276 djm 4339: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4340: switch (cctx->ai->ai_family) {
4341: case AF_UNIX:
4342: /* unix:pathname instead of host:port */
4343: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4344: strlcpy(ntop, "unix", sizeof(ntop));
4345: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4346: break;
4347: case AF_INET:
4348: case AF_INET6:
4349: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4350: ntop, sizeof(ntop), strport, sizeof(strport),
4351: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
4352: error("connect_next: getnameinfo failed");
4353: continue;
4354: }
4355: break;
4356: default:
1.41 markus 4357: continue;
4358: }
1.300 dtucker 4359: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4360: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4361: if (cctx->ai->ai_next == NULL)
1.186 djm 4362: error("socket: %.100s", strerror(errno));
4363: else
4364: verbose("socket: %.100s", strerror(errno));
1.41 markus 4365: continue;
4366: }
1.205 djm 4367: if (set_nonblock(sock) == -1)
1.403 djm 4368: fatal_f("set_nonblock(%d)", sock);
1.276 djm 4369: if (connect(sock, cctx->ai->ai_addr,
4370: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
4371: debug("connect_next: host %.100s ([%.100s]:%s): "
4372: "%.100s", cctx->host, ntop, strport,
1.41 markus 4373: strerror(errno));
1.276 djm 4374: saved_errno = errno;
1.41 markus 4375: close(sock);
1.276 djm 4376: errno = saved_errno;
1.89 stevesk 4377: continue; /* fail -- try next */
1.41 markus 4378: }
1.336 millert 4379: if (cctx->ai->ai_family != AF_UNIX)
4380: set_nodelay(sock);
1.276 djm 4381: debug("connect_next: host %.100s ([%.100s]:%s) "
4382: "in progress, fd=%d", cctx->host, ntop, strport, sock);
4383: cctx->ai = cctx->ai->ai_next;
4384: return sock;
4385: }
4386: return -1;
4387: }
1.41 markus 4388:
1.276 djm 4389: static void
4390: channel_connect_ctx_free(struct channel_connect *cctx)
4391: {
1.321 djm 4392: free(cctx->host);
1.336 millert 4393: if (cctx->aitop) {
4394: if (cctx->aitop->ai_family == AF_UNIX)
4395: free(cctx->aitop);
4396: else
4397: freeaddrinfo(cctx->aitop);
4398: }
1.329 tedu 4399: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4400: }
4401:
1.357 dtucker 4402: /*
1.372 markus 4403: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4404: * passing back the failure reason if appropriate.
4405: */
1.372 markus 4406: static int
4407: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4408: char *ctype, char *rname, struct channel_connect *cctx,
4409: int *reason, const char **errmsg)
1.276 djm 4410: {
4411: struct addrinfo hints;
4412: int gaierr;
4413: int sock = -1;
4414: char strport[NI_MAXSERV];
1.336 millert 4415:
4416: if (port == PORT_STREAMLOCAL) {
4417: struct sockaddr_un *sunaddr;
4418: struct addrinfo *ai;
4419:
4420: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4421: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4422: return -1;
1.336 millert 4423: }
4424:
4425: /*
4426: * Fake up a struct addrinfo for AF_UNIX connections.
4427: * channel_connect_ctx_free() must check ai_family
4428: * and use free() not freeaddirinfo() for AF_UNIX.
4429: */
4430: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4431: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4432: ai->ai_addr = (struct sockaddr *)(ai + 1);
4433: ai->ai_addrlen = sizeof(*sunaddr);
4434: ai->ai_family = AF_UNIX;
1.372 markus 4435: ai->ai_socktype = socktype;
1.336 millert 4436: ai->ai_protocol = PF_UNSPEC;
4437: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4438: sunaddr->sun_family = AF_UNIX;
4439: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4440: cctx->aitop = ai;
1.336 millert 4441: } else {
4442: memset(&hints, 0, sizeof(hints));
1.367 djm 4443: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4444: hints.ai_socktype = socktype;
1.336 millert 4445: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4446: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4447: != 0) {
4448: if (errmsg != NULL)
4449: *errmsg = ssh_gai_strerror(gaierr);
4450: if (reason != NULL)
4451: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4452: error("connect_to %.100s: unknown host (%s)", name,
4453: ssh_gai_strerror(gaierr));
1.372 markus 4454: return -1;
1.336 millert 4455: }
1.41 markus 4456: }
1.276 djm 4457:
1.372 markus 4458: cctx->host = xstrdup(name);
4459: cctx->port = port;
4460: cctx->ai = cctx->aitop;
1.276 djm 4461:
1.372 markus 4462: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4463: error("connect to %.100s port %d failed: %s",
1.336 millert 4464: name, port, strerror(errno));
1.372 markus 4465: return -1;
4466: }
4467:
4468: return sock;
4469: }
4470:
4471: /* Return CONNECTING channel to remote host:port or local socket path */
4472: static Channel *
4473: connect_to(struct ssh *ssh, const char *host, int port,
4474: char *ctype, char *rname)
4475: {
4476: struct channel_connect cctx;
4477: Channel *c;
4478: int sock;
4479:
4480: memset(&cctx, 0, sizeof(cctx));
4481: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4482: &cctx, NULL, NULL);
4483: if (sock == -1) {
1.276 djm 4484: channel_connect_ctx_free(&cctx);
4485: return NULL;
1.41 markus 4486: }
1.367 djm 4487: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4488: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4489: c->host_port = port;
4490: c->path = xstrdup(host);
1.276 djm 4491: c->connect_ctx = cctx;
1.372 markus 4492:
1.276 djm 4493: return c;
1.41 markus 4494: }
1.99 markus 4495:
1.354 markus 4496: /*
4497: * returns either the newly connected channel or the downstream channel
4498: * that needs to deal with this connection.
4499: */
1.276 djm 4500: Channel *
1.367 djm 4501: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4502: u_short listen_port, char *ctype, char *rname)
1.73 markus 4503: {
1.367 djm 4504: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4505: struct permission_set *pset = &sc->local_perms;
1.367 djm 4506: u_int i;
1.381 djm 4507: struct permission *perm;
1.99 markus 4508:
1.381 djm 4509: for (i = 0; i < pset->num_permitted_user; i++) {
4510: perm = &pset->permitted_user[i];
4511: if (open_listen_match_tcpip(perm,
4512: listen_host, listen_port, 1)) {
4513: if (perm->downstream)
4514: return perm->downstream;
4515: if (perm->port_to_connect == 0)
1.372 markus 4516: return rdynamic_connect_prepare(ssh,
4517: ctype, rname);
1.367 djm 4518: return connect_to(ssh,
1.381 djm 4519: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4520: ctype, rname);
1.276 djm 4521: }
4522: }
1.74 markus 4523: error("WARNING: Server requests forwarding for unknown listen_port %d",
4524: listen_port);
1.276 djm 4525: return NULL;
1.73 markus 4526: }
4527:
1.336 millert 4528: Channel *
1.367 djm 4529: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4530: char *ctype, char *rname)
1.336 millert 4531: {
1.367 djm 4532: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4533: struct permission_set *pset = &sc->local_perms;
1.367 djm 4534: u_int i;
1.381 djm 4535: struct permission *perm;
1.336 millert 4536:
1.381 djm 4537: for (i = 0; i < pset->num_permitted_user; i++) {
4538: perm = &pset->permitted_user[i];
4539: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4540: return connect_to(ssh,
1.381 djm 4541: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4542: ctype, rname);
1.336 millert 4543: }
4544: }
4545: error("WARNING: Server requests forwarding for unknown path %.100s",
4546: path);
4547: return NULL;
4548: }
4549:
1.99 markus 4550: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4551: Channel *
1.367 djm 4552: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4553: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4554: {
1.367 djm 4555: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4556: struct permission_set *pset = &sc->local_perms;
1.372 markus 4557: struct channel_connect cctx;
4558: Channel *c;
1.367 djm 4559: u_int i, permit, permit_adm = 1;
1.372 markus 4560: int sock;
1.381 djm 4561: struct permission *perm;
1.99 markus 4562:
1.381 djm 4563: permit = pset->all_permitted;
1.99 markus 4564: if (!permit) {
1.381 djm 4565: for (i = 0; i < pset->num_permitted_user; i++) {
4566: perm = &pset->permitted_user[i];
4567: if (open_match(perm, host, port)) {
1.99 markus 4568: permit = 1;
1.333 markus 4569: break;
4570: }
1.367 djm 4571: }
1.257 dtucker 4572: }
1.99 markus 4573:
1.381 djm 4574: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4575: permit_adm = 0;
1.381 djm 4576: for (i = 0; i < pset->num_permitted_admin; i++) {
4577: perm = &pset->permitted_admin[i];
4578: if (open_match(perm, host, port)) {
1.257 dtucker 4579: permit_adm = 1;
1.333 markus 4580: break;
4581: }
1.367 djm 4582: }
1.99 markus 4583: }
1.257 dtucker 4584:
4585: if (!permit || !permit_adm) {
1.391 florian 4586: logit("Received request from %.100s port %d to connect to "
4587: "host %.100s port %d, but the request was denied.",
4588: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4589: if (reason != NULL)
4590: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4591: return NULL;
1.99 markus 4592: }
1.372 markus 4593:
4594: memset(&cctx, 0, sizeof(cctx));
4595: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4596: &cctx, reason, errmsg);
4597: if (sock == -1) {
4598: channel_connect_ctx_free(&cctx);
4599: return NULL;
4600: }
4601:
4602: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4603: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4604: c->host_port = port;
4605: c->path = xstrdup(host);
4606: c->connect_ctx = cctx;
4607:
4608: return c;
1.336 millert 4609: }
4610:
4611: /* Check if connecting to that path is permitted and connect. */
4612: Channel *
1.367 djm 4613: channel_connect_to_path(struct ssh *ssh, const char *path,
4614: char *ctype, char *rname)
1.336 millert 4615: {
1.367 djm 4616: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4617: struct permission_set *pset = &sc->local_perms;
1.367 djm 4618: u_int i, permit, permit_adm = 1;
1.381 djm 4619: struct permission *perm;
1.336 millert 4620:
1.381 djm 4621: permit = pset->all_permitted;
1.336 millert 4622: if (!permit) {
1.381 djm 4623: for (i = 0; i < pset->num_permitted_user; i++) {
4624: perm = &pset->permitted_user[i];
4625: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4626: permit = 1;
4627: break;
4628: }
1.367 djm 4629: }
1.336 millert 4630: }
4631:
1.381 djm 4632: if (pset->num_permitted_admin > 0) {
1.336 millert 4633: permit_adm = 0;
1.381 djm 4634: for (i = 0; i < pset->num_permitted_admin; i++) {
4635: perm = &pset->permitted_admin[i];
4636: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4637: permit_adm = 1;
4638: break;
4639: }
1.367 djm 4640: }
1.336 millert 4641: }
4642:
4643: if (!permit || !permit_adm) {
4644: logit("Received request to connect to path %.100s, "
4645: "but the request was denied.", path);
4646: return NULL;
4647: }
1.367 djm 4648: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4649: }
4650:
4651: void
1.367 djm 4652: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4653: {
1.367 djm 4654: struct ssh_channels *sc = ssh->chanctxt;
4655: struct winsize ws;
4656: int r;
1.209 avsm 4657: u_int i;
1.204 djm 4658:
1.367 djm 4659: for (i = 0; i < sc->channels_alloc; i++) {
4660: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4661: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4662: continue;
1.393 deraadt 4663: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4664: continue;
1.367 djm 4665: channel_request_start(ssh, i, "window-change", 0);
4666: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4667: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4668: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4669: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4670: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4671: fatal_fr(r, "channel %u; send window-change", i);
1.204 djm 4672: }
1.372 markus 4673: }
4674:
4675: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4676: static Channel *
4677: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4678: {
4679: Channel *c;
4680: int r;
4681:
4682: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4683: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4684: c->host_port = 0;
4685: c->path = NULL;
4686:
4687: /*
4688: * We need to open the channel before we have a FD,
4689: * so that we can get SOCKS header from peer.
4690: */
4691: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4692: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4693: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4694: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 4695: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0)
4696: fatal_fr(r, "channel %i; confirm", c->self);
1.372 markus 4697: return c;
4698: }
4699:
4700: /* Return CONNECTING socket to remote host:port or local socket path */
4701: static int
4702: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4703: {
1.405 markus 4704: struct ssh_channels *sc = ssh->chanctxt;
4705: struct permission_set *pset = &sc->local_perms;
4706: struct permission *perm;
1.372 markus 4707: struct channel_connect cctx;
1.405 markus 4708: u_int i, permit_adm = 1;
1.372 markus 4709: int sock;
1.405 markus 4710:
4711: if (pset->num_permitted_admin > 0) {
4712: permit_adm = 0;
4713: for (i = 0; i < pset->num_permitted_admin; i++) {
4714: perm = &pset->permitted_admin[i];
4715: if (open_match(perm, c->path, c->host_port)) {
4716: permit_adm = 1;
4717: break;
4718: }
4719: }
4720: }
4721: if (!permit_adm) {
4722: debug_f("requested forward not permitted");
4723: return -1;
4724: }
1.372 markus 4725:
4726: memset(&cctx, 0, sizeof(cctx));
4727: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4728: NULL, &cctx, NULL, NULL);
4729: if (sock == -1)
4730: channel_connect_ctx_free(&cctx);
4731: else {
4732: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4733: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4734: c->connect_ctx = cctx;
4735: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4736: }
4737: return sock;
1.99 markus 4738: }
4739:
1.121 markus 4740: /* -- X11 forwarding */
1.1 deraadt 4741:
1.27 markus 4742: /*
4743: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4744: * Returns 0 and a suitable display number for the DISPLAY variable
4745: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4746: */
1.141 stevesk 4747: int
1.367 djm 4748: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4749: int x11_use_localhost, int single_connection,
4750: u_int *display_numberp, int **chanids)
1.1 deraadt 4751: {
1.149 markus 4752: Channel *nc = NULL;
1.31 markus 4753: int display_number, sock;
4754: u_short port;
1.35 markus 4755: struct addrinfo hints, *ai, *aitop;
4756: char strport[NI_MAXSERV];
4757: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4758:
1.224 markus 4759: if (chanids == NULL)
4760: return -1;
4761:
1.33 markus 4762: for (display_number = x11_display_offset;
1.148 deraadt 4763: display_number < MAX_DISPLAYS;
4764: display_number++) {
1.25 markus 4765: port = 6000 + display_number;
1.35 markus 4766: memset(&hints, 0, sizeof(hints));
1.367 djm 4767: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4768: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4769: hints.ai_socktype = SOCK_STREAM;
4770: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4771: if ((gaierr = getaddrinfo(NULL, strport,
4772: &hints, &aitop)) != 0) {
1.271 dtucker 4773: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4774: return -1;
1.25 markus 4775: }
1.35 markus 4776: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4777: if (ai->ai_family != AF_INET &&
4778: ai->ai_family != AF_INET6)
1.35 markus 4779: continue;
1.300 dtucker 4780: sock = socket(ai->ai_family, ai->ai_socktype,
4781: ai->ai_protocol);
1.393 deraadt 4782: if (sock == -1) {
1.35 markus 4783: error("socket: %.100s", strerror(errno));
1.203 markus 4784: freeaddrinfo(aitop);
1.141 stevesk 4785: return -1;
1.35 markus 4786: }
1.376 djm 4787: set_reuseaddr(sock);
1.393 deraadt 4788: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.403 djm 4789: debug2_f("bind port %d: %.100s", port,
4790: strerror(errno));
1.35 markus 4791: close(sock);
1.367 djm 4792: for (n = 0; n < num_socks; n++)
1.35 markus 4793: close(socks[n]);
4794: num_socks = 0;
4795: break;
4796: }
4797: socks[num_socks++] = sock;
4798: if (num_socks == NUM_SOCKS)
4799: break;
1.25 markus 4800: }
1.83 stevesk 4801: freeaddrinfo(aitop);
1.35 markus 4802: if (num_socks > 0)
4803: break;
1.25 markus 4804: }
4805: if (display_number >= MAX_DISPLAYS) {
4806: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4807: return -1;
1.25 markus 4808: }
4809: /* Start listening for connections on the socket. */
1.35 markus 4810: for (n = 0; n < num_socks; n++) {
4811: sock = socks[n];
1.393 deraadt 4812: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 4813: error("listen: %.100s", strerror(errno));
4814: close(sock);
1.141 stevesk 4815: return -1;
1.35 markus 4816: }
1.25 markus 4817: }
1.35 markus 4818:
4819: /* Allocate a channel for each socket. */
1.242 djm 4820: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4821: for (n = 0; n < num_socks; n++) {
4822: sock = socks[n];
1.367 djm 4823: nc = channel_new(ssh, "x11 listener",
1.51 markus 4824: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4825: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4826: 0, "X11 inet listener", 1);
1.167 markus 4827: nc->single_connection = single_connection;
1.224 markus 4828: (*chanids)[n] = nc->self;
1.35 markus 4829: }
1.224 markus 4830: (*chanids)[n] = -1;
1.1 deraadt 4831:
1.141 stevesk 4832: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4833: *display_numberp = display_number;
1.367 djm 4834: return 0;
1.1 deraadt 4835: }
4836:
1.127 itojun 4837: static int
1.77 markus 4838: connect_local_xsocket(u_int dnr)
1.1 deraadt 4839: {
1.25 markus 4840: int sock;
4841: struct sockaddr_un addr;
4842:
1.147 stevesk 4843: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 deraadt 4844: if (sock == -1)
1.147 stevesk 4845: error("socket: %.100s", strerror(errno));
4846: memset(&addr, 0, sizeof(addr));
4847: addr.sun_family = AF_UNIX;
4848: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4849: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4850: return sock;
4851: close(sock);
1.25 markus 4852: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4853: return -1;
1.1 deraadt 4854: }
4855:
1.51 markus 4856: int
1.367 djm 4857: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4858: {
1.248 deraadt 4859: u_int display_number;
1.25 markus 4860: const char *display;
1.51 markus 4861: char buf[1024], *cp;
1.35 markus 4862: struct addrinfo hints, *ai, *aitop;
4863: char strport[NI_MAXSERV];
1.248 deraadt 4864: int gaierr, sock = 0;
1.25 markus 4865:
4866: /* Try to open a socket for the local X server. */
4867: display = getenv("DISPLAY");
4868: if (!display) {
4869: error("DISPLAY not set.");
1.51 markus 4870: return -1;
1.25 markus 4871: }
1.27 markus 4872: /*
4873: * Now we decode the value of the DISPLAY variable and make a
4874: * connection to the real X server.
4875: */
4876:
4877: /*
4878: * Check if it is a unix domain socket. Unix domain displays are in
4879: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4880: */
1.25 markus 4881: if (strncmp(display, "unix:", 5) == 0 ||
4882: display[0] == ':') {
4883: /* Connect to the unix domain socket. */
1.367 djm 4884: if (sscanf(strrchr(display, ':') + 1, "%u",
4885: &display_number) != 1) {
4886: error("Could not parse display number from DISPLAY: "
4887: "%.100s", display);
1.51 markus 4888: return -1;
1.25 markus 4889: }
4890: /* Create a socket. */
4891: sock = connect_local_xsocket(display_number);
4892: if (sock < 0)
1.51 markus 4893: return -1;
1.25 markus 4894:
4895: /* OK, we now have a connection to the display. */
1.51 markus 4896: return sock;
1.25 markus 4897: }
1.27 markus 4898: /*
4899: * Connect to an inet socket. The DISPLAY value is supposedly
4900: * hostname:d[.s], where hostname may also be numeric IP address.
4901: */
1.145 stevesk 4902: strlcpy(buf, display, sizeof(buf));
1.25 markus 4903: cp = strchr(buf, ':');
4904: if (!cp) {
4905: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4906: return -1;
1.25 markus 4907: }
4908: *cp = 0;
1.367 djm 4909: /*
4910: * buf now contains the host name. But first we parse the
4911: * display number.
4912: */
1.248 deraadt 4913: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4914: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4915: display);
1.51 markus 4916: return -1;
1.25 markus 4917: }
1.35 markus 4918:
4919: /* Look up the host address */
4920: memset(&hints, 0, sizeof(hints));
1.367 djm 4921: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4922: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4923: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4924: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4925: error("%.100s: unknown host. (%s)", buf,
4926: ssh_gai_strerror(gaierr));
1.51 markus 4927: return -1;
1.25 markus 4928: }
1.35 markus 4929: for (ai = aitop; ai; ai = ai->ai_next) {
4930: /* Create a socket. */
1.300 dtucker 4931: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 4932: if (sock == -1) {
1.194 markus 4933: debug2("socket: %.100s", strerror(errno));
1.41 markus 4934: continue;
4935: }
4936: /* Connect it to the display. */
1.393 deraadt 4937: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 4938: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4939: 6000 + display_number, strerror(errno));
4940: close(sock);
4941: continue;
4942: }
4943: /* Success */
4944: break;
1.35 markus 4945: }
4946: freeaddrinfo(aitop);
4947: if (!ai) {
1.367 djm 4948: error("connect %.100s port %u: %.100s", buf,
4949: 6000 + display_number, strerror(errno));
1.51 markus 4950: return -1;
1.25 markus 4951: }
1.162 stevesk 4952: set_nodelay(sock);
1.51 markus 4953: return sock;
4954: }
4955:
4956: /*
1.27 markus 4957: * Requests forwarding of X11 connections, generates fake authentication
4958: * data, and enables authentication spoofing.
1.121 markus 4959: * This should be called in the client only.
1.27 markus 4960: */
1.49 markus 4961: void
1.367 djm 4962: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4963: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4964: {
1.367 djm 4965: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4966: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4967: u_int i, value;
1.367 djm 4968: const char *cp;
1.25 markus 4969: char *new_data;
1.367 djm 4970: int r, screen_number;
1.25 markus 4971:
1.367 djm 4972: if (sc->x11_saved_display == NULL)
4973: sc->x11_saved_display = xstrdup(disp);
4974: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4975: error("x11_request_forwarding_with_spoofing: different "
4976: "$DISPLAY already forwarded");
4977: return;
4978: }
4979:
1.266 djm 4980: cp = strchr(disp, ':');
1.25 markus 4981: if (cp)
4982: cp = strchr(cp, '.');
4983: if (cp)
1.245 deraadt 4984: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4985: else
4986: screen_number = 0;
4987:
1.367 djm 4988: if (sc->x11_saved_proto == NULL) {
1.219 djm 4989: /* Save protocol name. */
1.367 djm 4990: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4991:
4992: /* Extract real authentication data. */
1.367 djm 4993: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4994: for (i = 0; i < data_len; i++) {
1.403 djm 4995: if (sscanf(data + 2 * i, "%2x", &value) != 1) {
1.219 djm 4996: fatal("x11_request_forwarding: bad "
4997: "authentication data: %.100s", data);
1.403 djm 4998: }
1.367 djm 4999: sc->x11_saved_data[i] = value;
1.219 djm 5000: }
1.367 djm 5001: sc->x11_saved_data_len = data_len;
1.353 natano 5002:
5003: /* Generate fake data of the same length. */
1.367 djm 5004: sc->x11_fake_data = xmalloc(data_len);
5005: arc4random_buf(sc->x11_fake_data, data_len);
5006: sc->x11_fake_data_len = data_len;
1.25 markus 5007: }
5008:
5009: /* Convert the fake data into hex. */
1.367 djm 5010: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 5011:
5012: /* Send the request packet. */
1.367 djm 5013: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
5014: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
5015: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
5016: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
5017: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
5018: (r = sshpkt_send(ssh)) != 0 ||
5019: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 5020: fatal_fr(r, "send x11-req");
1.321 djm 5021: free(new_data);
1.1 deraadt 5022: }
![[BACK]](/icons/back.gif){kind=icon}
Return to channels.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh