Annotation of src/usr.bin/ssh/channels.c, Revision 1.402
1.402 ! djm 1: /* $OpenBSD: channels.c,v 1.401 2020/07/03 07:25:18 djm Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.336 millert 43: #include <sys/stat.h>
1.234 stevesk 44: #include <sys/ioctl.h>
1.235 stevesk 45: #include <sys/un.h>
1.251 stevesk 46: #include <sys/socket.h>
1.261 stevesk 47: #include <sys/time.h>
1.275 djm 48: #include <sys/queue.h>
1.251 stevesk 49:
50: #include <netinet/in.h>
51: #include <arpa/inet.h>
1.233 stevesk 52:
1.254 stevesk 53: #include <errno.h>
1.298 dtucker 54: #include <fcntl.h>
1.367 djm 55: #include <limits.h>
1.255 stevesk 56: #include <netdb.h>
1.367 djm 57: #include <stdarg.h>
1.341 millert 58: #include <stdint.h>
1.263 stevesk 59: #include <stdio.h>
1.262 stevesk 60: #include <stdlib.h>
1.260 stevesk 61: #include <string.h>
1.233 stevesk 62: #include <termios.h>
1.256 stevesk 63: #include <unistd.h>
1.1 deraadt 64:
1.265 deraadt 65: #include "xmalloc.h"
1.1 deraadt 66: #include "ssh.h"
1.82 markus 67: #include "ssh2.h"
1.354 markus 68: #include "ssherr.h"
1.367 djm 69: #include "sshbuf.h"
1.1 deraadt 70: #include "packet.h"
1.82 markus 71: #include "log.h"
72: #include "misc.h"
1.14 markus 73: #include "channels.h"
74: #include "compat.h"
1.82 markus 75: #include "canohost.h"
1.383 markus 76: #include "sshkey.h"
1.64 markus 77: #include "authfd.h"
1.147 stevesk 78: #include "pathnames.h"
1.381 djm 79: #include "match.h"
1.388 djm 80:
1.367 djm 81: /* -- agent forwarding */
82: #define NUM_SOCKS 10
1.12 markus 83:
1.367 djm 84: /* -- tcp forwarding */
85: /* special-case port number meaning allow any port */
86: #define FWD_PERMIT_ANY_PORT 0
1.1 deraadt 87:
1.367 djm 88: /* special-case wildcard meaning allow any host */
89: #define FWD_PERMIT_ANY_HOST "*"
1.1 deraadt 90:
1.367 djm 91: /* -- X11 forwarding */
92: /* Maximum number of fake X11 displays to try. */
93: #define MAX_DISPLAYS 1000
1.1 deraadt 94:
1.381 djm 95: /* Per-channel callback for pre/post select() actions */
96: typedef void chan_fn(struct ssh *, Channel *c,
97: fd_set *readset, fd_set *writeset);
98:
1.27 markus 99: /*
100: * Data structure for storing which hosts are permitted for forward requests.
101: * The local sides of any remote forwards are stored in this array to prevent
102: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
103: * network (which might be behind a firewall).
104: */
1.336 millert 105: /* XXX: streamlocal wants a path instead of host:port */
106: /* Overload host_to_connect; we could just make this match Forward */
107: /* XXX - can we use listen_host instead of listen_path? */
1.381 djm 108: struct permission {
1.41 markus 109: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 110: int port_to_connect; /* Connect to 'port'. */
1.333 markus 111: char *listen_host; /* Remote side should listen address. */
1.336 millert 112: char *listen_path; /* Remote side should listen path. */
113: int listen_port; /* Remote side should listen port. */
1.354 markus 114: Channel *downstream; /* Downstream mux*/
1.381 djm 115: };
116:
117: /*
118: * Stores the forwarding permission state for a single direction (local or
119: * remote).
120: */
121: struct permission_set {
122: /*
123: * List of all local permitted host/port pairs to allow for the
124: * user.
125: */
126: u_int num_permitted_user;
127: struct permission *permitted_user;
1.1 deraadt 128:
1.381 djm 129: /*
130: * List of all permitted host/port pairs to allow for the admin.
131: */
132: u_int num_permitted_admin;
133: struct permission *permitted_admin;
134:
135: /*
136: * If this is true, all opens/listens are permitted. This is the
137: * case on the server on which we have to trust the client anyway,
138: * and the user could do anything after logging in.
139: */
140: int all_permitted;
141: };
1.121 markus 142:
1.367 djm 143: /* Master structure for channels state */
144: struct ssh_channels {
145: /*
146: * Pointer to an array containing all allocated channels. The array
147: * is dynamically extended as needed.
148: */
149: Channel **channels;
1.257 dtucker 150:
1.367 djm 151: /*
152: * Size of the channel array. All slots of the array must always be
153: * initialized (at least the type field); unused slots set to NULL
154: */
155: u_int channels_alloc;
1.257 dtucker 156:
1.367 djm 157: /*
158: * Maximum file descriptor value used in any of the channels. This is
159: * updated in channel_new.
160: */
161: int channel_max_fd;
1.257 dtucker 162:
1.367 djm 163: /*
164: * 'channel_pre*' are called just before select() to add any bits
165: * relevant to channels in the select bitmasks.
166: *
167: * 'channel_post*': perform any appropriate operations for
168: * channels which have events pending.
169: */
170: chan_fn **channel_pre;
171: chan_fn **channel_post;
1.314 dtucker 172:
1.367 djm 173: /* -- tcp forwarding */
1.381 djm 174: struct permission_set local_perms;
175: struct permission_set remote_perms;
1.219 djm 176:
1.367 djm 177: /* -- X11 forwarding */
1.121 markus 178:
1.367 djm 179: /* Saved X11 local (client) display. */
180: char *x11_saved_display;
1.121 markus 181:
1.367 djm 182: /* Saved X11 authentication protocol name. */
183: char *x11_saved_proto;
1.347 djm 184:
1.367 djm 185: /* Saved X11 authentication data. This is the real data. */
186: char *x11_saved_data;
187: u_int x11_saved_data_len;
1.121 markus 188:
1.367 djm 189: /* Deadline after which all X11 connections are refused */
190: u_int x11_refuse_time;
1.121 markus 191:
1.367 djm 192: /*
193: * Fake X11 authentication data. This is what the server will be
194: * sending us; we should replace any occurrences of this by the
195: * real data.
196: */
197: u_char *x11_fake_data;
198: u_int x11_fake_data_len;
1.121 markus 199:
1.367 djm 200: /* AF_UNSPEC or AF_INET or AF_INET6 */
201: int IPv4or6;
202: };
1.1 deraadt 203:
1.121 markus 204: /* helper */
1.367 djm 205: static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
1.354 markus 206: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 207:
1.276 djm 208: /* non-blocking connect helpers */
209: static int connect_next(struct channel_connect *);
210: static void channel_connect_ctx_free(struct channel_connect *);
1.372 markus 211: static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
212: static int rdynamic_connect_finish(struct ssh *, Channel *);
1.276 djm 213:
1.367 djm 214: /* Setup helper */
215: static void channel_handler_init(struct ssh_channels *sc);
216:
1.121 markus 217: /* -- channel core */
1.41 markus 218:
1.367 djm 219: void
220: channel_init_channels(struct ssh *ssh)
221: {
222: struct ssh_channels *sc;
223:
1.387 djm 224: if ((sc = calloc(1, sizeof(*sc))) == NULL)
1.367 djm 225: fatal("%s: allocation failed", __func__);
226: sc->channels_alloc = 10;
227: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
228: sc->IPv4or6 = AF_UNSPEC;
229: channel_handler_init(sc);
230:
231: ssh->chanctxt = sc;
232: }
233:
1.41 markus 234: Channel *
1.367 djm 235: channel_by_id(struct ssh *ssh, int id)
1.41 markus 236: {
237: Channel *c;
1.113 markus 238:
1.367 djm 239: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
240: logit("%s: %d: bad id", __func__, id);
1.41 markus 241: return NULL;
242: }
1.367 djm 243: c = ssh->chanctxt->channels[id];
1.113 markus 244: if (c == NULL) {
1.367 djm 245: logit("%s: %d: bad id: channel free", __func__, id);
1.41 markus 246: return NULL;
247: }
248: return c;
1.55 markus 249: }
250:
1.354 markus 251: Channel *
1.368 djm 252: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 253: {
254: Channel *c;
255: u_int i;
256:
1.367 djm 257: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
258: c = ssh->chanctxt->channels[i];
1.368 djm 259: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 260: return c;
261: }
262: return NULL;
263: }
264:
1.27 markus 265: /*
1.229 markus 266: * Returns the channel if it is allowed to receive protocol messages.
267: * Private channels, like listening sockets, may not receive messages.
268: */
269: Channel *
1.367 djm 270: channel_lookup(struct ssh *ssh, int id)
1.229 markus 271: {
272: Channel *c;
273:
1.367 djm 274: if ((c = channel_by_id(ssh, id)) == NULL)
275: return NULL;
1.229 markus 276:
1.237 deraadt 277: switch (c->type) {
1.229 markus 278: case SSH_CHANNEL_X11_OPEN:
279: case SSH_CHANNEL_LARVAL:
280: case SSH_CHANNEL_CONNECTING:
281: case SSH_CHANNEL_DYNAMIC:
1.372 markus 282: case SSH_CHANNEL_RDYNAMIC_OPEN:
283: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 284: case SSH_CHANNEL_OPENING:
285: case SSH_CHANNEL_OPEN:
1.323 dtucker 286: case SSH_CHANNEL_ABANDONED:
1.354 markus 287: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 288: return c;
1.229 markus 289: }
290: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 291: return NULL;
1.229 markus 292: }
293:
294: /*
1.55 markus 295: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 296: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 297: */
1.127 itojun 298: static void
1.367 djm 299: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 300: int extusage, int nonblock, int is_tty)
1.1 deraadt 301: {
1.367 djm 302: struct ssh_channels *sc = ssh->chanctxt;
303:
1.25 markus 304: /* Update the maximum file descriptor value. */
1.367 djm 305: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, rfd);
306: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, wfd);
307: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, efd);
1.84 markus 308:
1.298 dtucker 309: if (rfd != -1)
310: fcntl(rfd, F_SETFD, FD_CLOEXEC);
311: if (wfd != -1 && wfd != rfd)
312: fcntl(wfd, F_SETFD, FD_CLOEXEC);
313: if (efd != -1 && efd != rfd && efd != wfd)
314: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 315:
1.52 markus 316: c->rfd = rfd;
317: c->wfd = wfd;
318: c->sock = (rfd == wfd) ? rfd : -1;
319: c->efd = efd;
320: c->extended_usage = extusage;
1.71 markus 321:
1.282 dtucker 322: if ((c->isatty = is_tty) != 0)
1.194 markus 323: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 324:
1.71 markus 325: /* enable nonblocking mode */
326: if (nonblock) {
327: if (rfd != -1)
328: set_nonblock(rfd);
329: if (wfd != -1)
330: set_nonblock(wfd);
331: if (efd != -1)
332: set_nonblock(efd);
333: }
1.52 markus 334: }
335:
336: /*
337: * Allocate a new channel object and set its type and socket. This will cause
338: * remote_name to be freed.
339: */
1.113 markus 340: Channel *
1.367 djm 341: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 342: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 343: {
1.367 djm 344: struct ssh_channels *sc = ssh->chanctxt;
345: u_int i, found;
1.52 markus 346: Channel *c;
1.402 ! djm 347: int r;
1.25 markus 348:
349: /* Try to find a free slot where to put the new channel. */
1.367 djm 350: for (i = 0; i < sc->channels_alloc; i++) {
351: if (sc->channels[i] == NULL) {
1.25 markus 352: /* Found a free slot. */
1.367 djm 353: found = i;
1.25 markus 354: break;
355: }
1.367 djm 356: }
357: if (i >= sc->channels_alloc) {
358: /*
359: * There are no free slots. Take last+1 slot and expand
360: * the array.
361: */
362: found = sc->channels_alloc;
363: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
364: fatal("%s: internal error: channels_alloc %d too big",
365: __func__, sc->channels_alloc);
366: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
367: sc->channels_alloc + 10, sizeof(*sc->channels));
368: sc->channels_alloc += 10;
369: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 370: }
1.113 markus 371: /* Initialize and return new channel. */
1.367 djm 372: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
373: if ((c->input = sshbuf_new()) == NULL ||
374: (c->output = sshbuf_new()) == NULL ||
375: (c->extended = sshbuf_new()) == NULL)
376: fatal("%s: sshbuf_new failed", __func__);
1.402 ! djm 377: if ((r = sshbuf_set_max_size(c->input, CHAN_INPUT_MAX)) != 0)
! 378: fatal("%s: sshbuf_set_max_size: %s", __func__, ssh_err(r));
1.159 markus 379: c->ostate = CHAN_OUTPUT_OPEN;
380: c->istate = CHAN_INPUT_OPEN;
1.367 djm 381: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 382: c->self = found;
383: c->type = type;
1.41 markus 384: c->ctype = ctype;
1.51 markus 385: c->local_window = window;
386: c->local_window_max = window;
387: c->local_maxpacket = maxpack;
1.190 markus 388: c->remote_name = xstrdup(remote_name);
1.302 djm 389: c->ctl_chan = -1;
1.299 markus 390: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 391: TAILQ_INIT(&c->status_confirms);
1.25 markus 392: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 393: return c;
1.1 deraadt 394: }
1.52 markus 395:
1.367 djm 396: static void
397: channel_find_maxfd(struct ssh_channels *sc)
1.132 markus 398: {
1.209 avsm 399: u_int i;
400: int max = 0;
1.132 markus 401: Channel *c;
402:
1.367 djm 403: for (i = 0; i < sc->channels_alloc; i++) {
404: c = sc->channels[i];
1.132 markus 405: if (c != NULL) {
1.352 deraadt 406: max = MAXIMUM(max, c->rfd);
407: max = MAXIMUM(max, c->wfd);
408: max = MAXIMUM(max, c->efd);
1.132 markus 409: }
410: }
1.367 djm 411: sc->channel_max_fd = max;
1.132 markus 412: }
413:
414: int
1.367 djm 415: channel_close_fd(struct ssh *ssh, int *fdp)
1.132 markus 416: {
1.367 djm 417: struct ssh_channels *sc = ssh->chanctxt;
1.132 markus 418: int ret = 0, fd = *fdp;
419:
420: if (fd != -1) {
421: ret = close(fd);
422: *fdp = -1;
1.367 djm 423: if (fd == sc->channel_max_fd)
424: channel_find_maxfd(sc);
1.132 markus 425: }
426: return ret;
427: }
428:
1.52 markus 429: /* Close all channel fd/socket. */
1.127 itojun 430: static void
1.367 djm 431: channel_close_fds(struct ssh *ssh, Channel *c)
432: {
1.379 tb 433: int sock = c->sock, rfd = c->rfd, wfd = c->wfd, efd = c->efd;
434:
1.367 djm 435: channel_close_fd(ssh, &c->sock);
1.379 tb 436: if (rfd != sock)
437: channel_close_fd(ssh, &c->rfd);
438: if (wfd != sock && wfd != rfd)
439: channel_close_fd(ssh, &c->wfd);
440: if (efd != sock && efd != rfd && efd != wfd)
441: channel_close_fd(ssh, &c->efd);
1.367 djm 442: }
443:
444: static void
1.381 djm 445: fwd_perm_clear(struct permission *perm)
1.52 markus 446: {
1.381 djm 447: free(perm->host_to_connect);
448: free(perm->listen_host);
449: free(perm->listen_path);
1.398 dtucker 450: memset(perm, 0, sizeof(*perm));
1.367 djm 451: }
452:
1.381 djm 453: /* Returns an printable name for the specified forwarding permission list */
454: static const char *
455: fwd_ident(int who, int where)
456: {
457: if (who == FORWARD_ADM) {
458: if (where == FORWARD_LOCAL)
459: return "admin local";
460: else if (where == FORWARD_REMOTE)
461: return "admin remote";
462: } else if (who == FORWARD_USER) {
463: if (where == FORWARD_LOCAL)
464: return "user local";
465: else if (where == FORWARD_REMOTE)
466: return "user remote";
467: }
468: fatal("Unknown forward permission list %d/%d", who, where);
469: }
470:
471: /* Returns the forwarding permission list for the specified direction */
472: static struct permission_set *
473: permission_set_get(struct ssh *ssh, int where)
474: {
475: struct ssh_channels *sc = ssh->chanctxt;
1.367 djm 476:
1.381 djm 477: switch (where) {
478: case FORWARD_LOCAL:
479: return &sc->local_perms;
480: break;
481: case FORWARD_REMOTE:
482: return &sc->remote_perms;
483: break;
484: default:
485: fatal("%s: invalid forwarding direction %d", __func__, where);
486: }
487: }
488:
1.392 dtucker 489: /* Returns pointers to the specified forwarding list and its element count */
1.381 djm 490: static void
491: permission_set_get_array(struct ssh *ssh, int who, int where,
492: struct permission ***permpp, u_int **npermpp)
493: {
494: struct permission_set *pset = permission_set_get(ssh, where);
495:
496: switch (who) {
497: case FORWARD_USER:
498: *permpp = &pset->permitted_user;
499: *npermpp = &pset->num_permitted_user;
500: break;
501: case FORWARD_ADM:
502: *permpp = &pset->permitted_admin;
503: *npermpp = &pset->num_permitted_admin;
504: break;
505: default:
506: fatal("%s: invalid forwarding client %d", __func__, who);
507: }
508: }
509:
510: /* Adds an entry to the spcified forwarding list */
1.367 djm 511: static int
1.381 djm 512: permission_set_add(struct ssh *ssh, int who, int where,
1.367 djm 513: const char *host_to_connect, int port_to_connect,
514: const char *listen_host, const char *listen_path, int listen_port,
515: Channel *downstream)
516: {
1.381 djm 517: struct permission **permp;
518: u_int n, *npermp;
1.367 djm 519:
1.381 djm 520: permission_set_get_array(ssh, who, where, &permp, &npermp);
1.367 djm 521:
1.381 djm 522: if (*npermp >= INT_MAX)
523: fatal("%s: %s overflow", __func__, fwd_ident(who, where));
1.367 djm 524:
1.381 djm 525: *permp = xrecallocarray(*permp, *npermp, *npermp + 1, sizeof(**permp));
526: n = (*npermp)++;
1.367 djm 527: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
1.381 djm 528: (*permp)[n].host_to_connect = MAYBE_DUP(host_to_connect);
529: (*permp)[n].port_to_connect = port_to_connect;
530: (*permp)[n].listen_host = MAYBE_DUP(listen_host);
531: (*permp)[n].listen_path = MAYBE_DUP(listen_path);
532: (*permp)[n].listen_port = listen_port;
533: (*permp)[n].downstream = downstream;
1.367 djm 534: #undef MAYBE_DUP
535: return (int)n;
536: }
537:
538: static void
539: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
540: {
541: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 542: struct permission_set *pset = &sc->local_perms;
543: struct permission *perm;
1.367 djm 544: int r;
545: u_int i;
546:
1.381 djm 547: for (i = 0; i < pset->num_permitted_user; i++) {
548: perm = &pset->permitted_user[i];
549: if (perm->downstream != c)
1.367 djm 550: continue;
551:
552: /* cancel on the server, since mux client is gone */
553: debug("channel %d: cleanup remote forward for %s:%u",
1.381 djm 554: c->self, perm->listen_host, perm->listen_port);
1.367 djm 555: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
556: (r = sshpkt_put_cstring(ssh,
557: "cancel-tcpip-forward")) != 0 ||
558: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
559: (r = sshpkt_put_cstring(ssh,
1.381 djm 560: channel_rfwd_bind_host(perm->listen_host))) != 0 ||
561: (r = sshpkt_put_u32(ssh, perm->listen_port)) != 0 ||
1.367 djm 562: (r = sshpkt_send(ssh)) != 0) {
563: fatal("%s: channel %i: %s", __func__,
564: c->self, ssh_err(r));
565: }
1.381 djm 566: fwd_perm_clear(perm); /* unregister */
1.367 djm 567: }
1.121 markus 568: }
569:
570: /* Free the channel and close its fd/socket. */
571: void
1.367 djm 572: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 573: {
1.367 djm 574: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 575: char *s;
1.209 avsm 576: u_int i, n;
1.354 markus 577: Channel *other;
1.275 djm 578: struct channel_confirm *cc;
1.121 markus 579:
1.367 djm 580: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
581: if ((other = sc->channels[i]) == NULL)
582: continue;
583: n++;
584: /* detach from mux client and prepare for closing */
585: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
586: other->type == SSH_CHANNEL_MUX_PROXY &&
587: other->mux_ctx == c) {
588: other->mux_ctx = NULL;
589: other->type = SSH_CHANNEL_OPEN;
590: other->istate = CHAN_INPUT_CLOSED;
591: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 592: }
593: }
1.209 avsm 594: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 595: c->remote_name ? c->remote_name : "???", n);
596:
1.367 djm 597: if (c->type == SSH_CHANNEL_MUX_CLIENT)
598: mux_remove_remote_forwardings(ssh, c);
1.401 djm 599: else if (c->type == SSH_CHANNEL_MUX_LISTENER) {
600: free(c->mux_ctx);
601: c->mux_ctx = NULL;
602: }
1.354 markus 603:
1.384 markus 604: if (log_level_get() >= SYSLOG_LEVEL_DEBUG3) {
605: s = channel_open_message(ssh);
606: debug3("channel %d: status: %s", c->self, s);
607: free(s);
608: }
1.121 markus 609:
1.367 djm 610: channel_close_fds(ssh, c);
611: sshbuf_free(c->input);
612: sshbuf_free(c->output);
613: sshbuf_free(c->extended);
614: c->input = c->output = c->extended = NULL;
1.321 djm 615: free(c->remote_name);
616: c->remote_name = NULL;
617: free(c->path);
618: c->path = NULL;
619: free(c->listening_addr);
620: c->listening_addr = NULL;
1.275 djm 621: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
622: if (cc->abandon_cb != NULL)
1.367 djm 623: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 624: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 625: freezero(cc, sizeof(*cc));
1.275 djm 626: }
1.280 djm 627: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 628: c->filter_cleanup(ssh, c->self, c->filter_ctx);
629: sc->channels[c->self] = NULL;
1.396 jsg 630: freezero(c, sizeof(*c));
1.121 markus 631: }
632:
633: void
1.367 djm 634: channel_free_all(struct ssh *ssh)
1.121 markus 635: {
1.209 avsm 636: u_int i;
1.390 dtucker 637: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 638:
1.390 dtucker 639: for (i = 0; i < sc->channels_alloc; i++)
640: if (sc->channels[i] != NULL)
641: channel_free(ssh, sc->channels[i]);
642:
643: free(sc->channels);
644: sc->channels = NULL;
645: sc->channels_alloc = 0;
646: sc->channel_max_fd = 0;
647:
648: free(sc->x11_saved_display);
649: sc->x11_saved_display = NULL;
650:
651: free(sc->x11_saved_proto);
652: sc->x11_saved_proto = NULL;
653:
654: free(sc->x11_saved_data);
655: sc->x11_saved_data = NULL;
656: sc->x11_saved_data_len = 0;
657:
658: free(sc->x11_fake_data);
659: sc->x11_fake_data = NULL;
660: sc->x11_fake_data_len = 0;
1.131 markus 661: }
662:
1.121 markus 663: /*
664: * Closes the sockets/fds of all channels. This is used to close extra file
665: * descriptors after a fork.
666: */
667: void
1.367 djm 668: channel_close_all(struct ssh *ssh)
1.121 markus 669: {
1.209 avsm 670: u_int i;
1.121 markus 671:
1.367 djm 672: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
673: if (ssh->chanctxt->channels[i] != NULL)
674: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 675: }
676:
677: /*
1.131 markus 678: * Stop listening to channels.
679: */
680: void
1.367 djm 681: channel_stop_listening(struct ssh *ssh)
1.131 markus 682: {
1.209 avsm 683: u_int i;
1.131 markus 684: Channel *c;
685:
1.367 djm 686: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
687: c = ssh->chanctxt->channels[i];
1.131 markus 688: if (c != NULL) {
689: switch (c->type) {
690: case SSH_CHANNEL_AUTH_SOCKET:
691: case SSH_CHANNEL_PORT_LISTENER:
692: case SSH_CHANNEL_RPORT_LISTENER:
693: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 694: case SSH_CHANNEL_UNIX_LISTENER:
695: case SSH_CHANNEL_RUNIX_LISTENER:
1.367 djm 696: channel_close_fd(ssh, &c->sock);
697: channel_free(ssh, c);
1.131 markus 698: break;
699: }
700: }
701: }
702: }
703:
704: /*
1.121 markus 705: * Returns true if no channel has too much buffered data, and false if one or
706: * more channel is overfull.
707: */
708: int
1.367 djm 709: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 710: {
711: u_int i;
1.367 djm 712: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 713: Channel *c;
714:
1.367 djm 715: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
716: c = ssh->chanctxt->channels[i];
717: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
718: continue;
719: if (sshbuf_len(c->output) > maxsize) {
720: debug2("channel %d: big output buffer %zu > %u",
721: c->self, sshbuf_len(c->output), maxsize);
722: return 0;
1.121 markus 723: }
724: }
725: return 1;
726: }
727:
728: /* Returns true if any channel is still open. */
729: int
1.367 djm 730: channel_still_open(struct ssh *ssh)
1.121 markus 731: {
1.209 avsm 732: u_int i;
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];
1.121 markus 737: if (c == NULL)
738: continue;
739: switch (c->type) {
740: case SSH_CHANNEL_X11_LISTENER:
741: case SSH_CHANNEL_PORT_LISTENER:
742: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 743: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 744: case SSH_CHANNEL_CLOSED:
745: case SSH_CHANNEL_AUTH_SOCKET:
746: case SSH_CHANNEL_DYNAMIC:
1.372 markus 747: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 748: case SSH_CHANNEL_CONNECTING:
749: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 750: case SSH_CHANNEL_ABANDONED:
1.336 millert 751: case SSH_CHANNEL_UNIX_LISTENER:
752: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 753: continue;
754: case SSH_CHANNEL_LARVAL:
755: continue;
756: case SSH_CHANNEL_OPENING:
757: case SSH_CHANNEL_OPEN:
1.372 markus 758: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 759: case SSH_CHANNEL_X11_OPEN:
1.302 djm 760: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 761: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 762: return 1;
763: default:
1.358 djm 764: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 765: /* NOTREACHED */
766: }
767: }
768: return 0;
769: }
770:
771: /* Returns the id of an open channel suitable for keepaliving */
772: int
1.367 djm 773: channel_find_open(struct ssh *ssh)
1.121 markus 774: {
1.209 avsm 775: u_int i;
1.121 markus 776: Channel *c;
777:
1.367 djm 778: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
779: c = ssh->chanctxt->channels[i];
1.368 djm 780: if (c == NULL || !c->have_remote_id)
1.121 markus 781: continue;
782: switch (c->type) {
783: case SSH_CHANNEL_CLOSED:
784: case SSH_CHANNEL_DYNAMIC:
1.372 markus 785: case SSH_CHANNEL_RDYNAMIC_OPEN:
786: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 787: case SSH_CHANNEL_X11_LISTENER:
788: case SSH_CHANNEL_PORT_LISTENER:
789: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 790: case SSH_CHANNEL_MUX_LISTENER:
791: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 792: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 793: case SSH_CHANNEL_OPENING:
794: case SSH_CHANNEL_CONNECTING:
795: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 796: case SSH_CHANNEL_ABANDONED:
1.336 millert 797: case SSH_CHANNEL_UNIX_LISTENER:
798: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 799: continue;
800: case SSH_CHANNEL_LARVAL:
801: case SSH_CHANNEL_AUTH_SOCKET:
802: case SSH_CHANNEL_OPEN:
803: case SSH_CHANNEL_X11_OPEN:
804: return i;
805: default:
1.358 djm 806: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 807: /* NOTREACHED */
808: }
809: }
810: return -1;
811: }
812:
1.385 djm 813: /* Returns the state of the channel's extended usage flag */
814: const char *
815: channel_format_extended_usage(const Channel *c)
816: {
817: if (c->efd == -1)
818: return "closed";
819:
820: switch (c->extended_usage) {
821: case CHAN_EXTENDED_WRITE:
822: return "write";
823: case CHAN_EXTENDED_READ:
824: return "read";
825: case CHAN_EXTENDED_IGNORE:
826: return "ignore";
827: default:
828: return "UNKNOWN";
829: }
830: }
831:
1.386 djm 832: static char *
833: channel_format_status(const Channel *c)
834: {
835: char *ret = NULL;
836:
837: xasprintf(&ret, "t%d %s%u i%u/%zu o%u/%zu e[%s]/%zu "
838: "fd %d/%d/%d sock %d cc %d",
839: c->type,
840: c->have_remote_id ? "r" : "nr", c->remote_id,
841: c->istate, sshbuf_len(c->input),
842: c->ostate, sshbuf_len(c->output),
843: channel_format_extended_usage(c), sshbuf_len(c->extended),
844: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan);
845: return ret;
846: }
847:
1.121 markus 848: /*
849: * Returns a message describing the currently open forwarded connections,
850: * suitable for sending to the client. The message contains crlf pairs for
851: * newlines.
852: */
853: char *
1.367 djm 854: channel_open_message(struct ssh *ssh)
1.121 markus 855: {
1.367 djm 856: struct sshbuf *buf;
1.121 markus 857: Channel *c;
1.209 avsm 858: u_int i;
1.367 djm 859: int r;
1.386 djm 860: char *cp, *ret;
1.121 markus 861:
1.367 djm 862: if ((buf = sshbuf_new()) == NULL)
863: fatal("%s: sshbuf_new", __func__);
864: if ((r = sshbuf_putf(buf,
865: "The following connections are open:\r\n")) != 0)
866: fatal("%s: sshbuf_putf: %s", __func__, ssh_err(r));
867: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
868: c = ssh->chanctxt->channels[i];
1.121 markus 869: if (c == NULL)
870: continue;
871: switch (c->type) {
872: case SSH_CHANNEL_X11_LISTENER:
873: case SSH_CHANNEL_PORT_LISTENER:
874: case SSH_CHANNEL_RPORT_LISTENER:
875: case SSH_CHANNEL_CLOSED:
876: case SSH_CHANNEL_AUTH_SOCKET:
877: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 878: case SSH_CHANNEL_ABANDONED:
1.302 djm 879: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 880: case SSH_CHANNEL_UNIX_LISTENER:
881: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 882: continue;
883: case SSH_CHANNEL_LARVAL:
884: case SSH_CHANNEL_OPENING:
885: case SSH_CHANNEL_CONNECTING:
886: case SSH_CHANNEL_DYNAMIC:
1.372 markus 887: case SSH_CHANNEL_RDYNAMIC_OPEN:
888: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 889: case SSH_CHANNEL_OPEN:
890: case SSH_CHANNEL_X11_OPEN:
1.354 markus 891: case SSH_CHANNEL_MUX_PROXY:
892: case SSH_CHANNEL_MUX_CLIENT:
1.386 djm 893: cp = channel_format_status(c);
894: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
895: c->self, c->remote_name, cp)) != 0) {
896: free(cp);
1.367 djm 897: fatal("%s: sshbuf_putf: %s",
898: __func__, ssh_err(r));
1.386 djm 899: }
900: free(cp);
1.121 markus 901: continue;
902: default:
1.367 djm 903: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 904: /* NOTREACHED */
905: }
906: }
1.367 djm 907: if ((ret = sshbuf_dup_string(buf)) == NULL)
908: fatal("%s: sshbuf_dup_string", __func__);
909: sshbuf_free(buf);
910: return ret;
911: }
912:
913: static void
914: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
915: {
916: int r;
917:
918: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
919: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
920: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
921: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
922: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
923: fatal("%s: channel %i: open: %s", where, c->self, ssh_err(r));
924: }
1.121 markus 925: }
926:
927: void
1.367 djm 928: channel_send_open(struct ssh *ssh, int id)
1.121 markus 929: {
1.367 djm 930: Channel *c = channel_lookup(ssh, id);
931: int r;
1.180 deraadt 932:
1.121 markus 933: if (c == NULL) {
1.188 itojun 934: logit("channel_send_open: %d: bad id", id);
1.121 markus 935: return;
936: }
1.184 markus 937: debug2("channel %d: send open", id);
1.367 djm 938: open_preamble(ssh, __func__, c, c->ctype);
939: if ((r = sshpkt_send(ssh)) != 0)
940: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.121 markus 941: }
942:
943: void
1.367 djm 944: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 945: {
1.367 djm 946: Channel *c = channel_lookup(ssh, id);
947: int r;
1.180 deraadt 948:
1.121 markus 949: if (c == NULL) {
1.367 djm 950: logit("%s: %d: unknown channel id", __func__, id);
1.121 markus 951: return;
952: }
1.368 djm 953: if (!c->have_remote_id)
954: fatal(":%s: channel %d: no remote id", __func__, c->self);
955:
1.204 djm 956: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 957: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
958: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
959: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
960: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
961: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
962: }
1.121 markus 963: }
1.241 deraadt 964:
1.121 markus 965: void
1.367 djm 966: channel_register_status_confirm(struct ssh *ssh, int id,
967: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 968: {
969: struct channel_confirm *cc;
970: Channel *c;
971:
1.367 djm 972: if ((c = channel_lookup(ssh, id)) == NULL)
973: fatal("%s: %d: bad id", __func__, id);
1.275 djm 974:
1.327 djm 975: cc = xcalloc(1, sizeof(*cc));
1.275 djm 976: cc->cb = cb;
977: cc->abandon_cb = abandon_cb;
978: cc->ctx = ctx;
979: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
980: }
981:
982: void
1.367 djm 983: channel_register_open_confirm(struct ssh *ssh, int id,
984: channel_open_fn *fn, void *ctx)
1.121 markus 985: {
1.367 djm 986: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 987:
1.121 markus 988: if (c == NULL) {
1.367 djm 989: logit("%s: %d: bad id", __func__, id);
1.121 markus 990: return;
991: }
1.275 djm 992: c->open_confirm = fn;
993: c->open_confirm_ctx = ctx;
1.121 markus 994: }
1.241 deraadt 995:
1.121 markus 996: void
1.367 djm 997: channel_register_cleanup(struct ssh *ssh, int id,
998: channel_callback_fn *fn, int do_close)
1.121 markus 999: {
1.367 djm 1000: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1001:
1.121 markus 1002: if (c == NULL) {
1.367 djm 1003: logit("%s: %d: bad id", __func__, id);
1.121 markus 1004: return;
1005: }
1.131 markus 1006: c->detach_user = fn;
1.225 djm 1007: c->detach_close = do_close;
1.121 markus 1008: }
1.241 deraadt 1009:
1.121 markus 1010: void
1.367 djm 1011: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 1012: {
1.367 djm 1013: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1014:
1.121 markus 1015: if (c == NULL) {
1.367 djm 1016: logit("%s: %d: bad id", __func__, id);
1.121 markus 1017: return;
1.52 markus 1018: }
1.131 markus 1019: c->detach_user = NULL;
1.225 djm 1020: c->detach_close = 0;
1.121 markus 1021: }
1.241 deraadt 1022:
1.121 markus 1023: void
1.367 djm 1024: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1025: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1026: {
1.367 djm 1027: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1028:
1.121 markus 1029: if (c == NULL) {
1.367 djm 1030: logit("%s: %d: bad id", __func__, id);
1.121 markus 1031: return;
1.52 markus 1032: }
1.231 reyk 1033: c->input_filter = ifn;
1034: c->output_filter = ofn;
1.279 djm 1035: c->filter_ctx = ctx;
1.280 djm 1036: c->filter_cleanup = cfn;
1.52 markus 1037: }
1038:
1.49 markus 1039: void
1.367 djm 1040: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1041: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1042: {
1.367 djm 1043: Channel *c = channel_lookup(ssh, id);
1044: int r;
1.180 deraadt 1045:
1.121 markus 1046: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1047: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1048: if (!c->have_remote_id)
1049: fatal(":%s: channel %d: no remote id", __func__, c->self);
1050:
1.367 djm 1051: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1052: c->type = SSH_CHANNEL_OPEN;
1.168 markus 1053: c->local_window = c->local_window_max = window_max;
1.367 djm 1054:
1055: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1056: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1057: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1058: (r = sshpkt_send(ssh)) != 0)
1059: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.1 deraadt 1060: }
1061:
1.127 itojun 1062: static void
1.367 djm 1063: channel_pre_listener(struct ssh *ssh, Channel *c,
1064: fd_set *readset, fd_set *writeset)
1.41 markus 1065: {
1066: FD_SET(c->sock, readset);
1067: }
1068:
1.127 itojun 1069: static void
1.367 djm 1070: channel_pre_connecting(struct ssh *ssh, Channel *c,
1071: fd_set *readset, fd_set *writeset)
1.75 markus 1072: {
1073: debug3("channel %d: waiting for connection", c->self);
1074: FD_SET(c->sock, writeset);
1075: }
1076:
1.127 itojun 1077: static void
1.367 djm 1078: channel_pre_open(struct ssh *ssh, Channel *c,
1079: fd_set *readset, fd_set *writeset)
1.41 markus 1080: {
1.44 markus 1081: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1082: c->remote_window > 0 &&
1.367 djm 1083: sshbuf_len(c->input) < c->remote_window &&
1084: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.44 markus 1085: FD_SET(c->rfd, readset);
1086: if (c->ostate == CHAN_OUTPUT_OPEN ||
1087: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1088: if (sshbuf_len(c->output) > 0) {
1.44 markus 1089: FD_SET(c->wfd, writeset);
1090: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1091: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1092: debug2("channel %d: "
1093: "obuf_empty delayed efd %d/(%zu)", c->self,
1094: c->efd, sshbuf_len(c->extended));
1.172 markus 1095: else
1.367 djm 1096: chan_obuf_empty(ssh, c);
1.44 markus 1097: }
1098: }
1099: /** XXX check close conditions, too */
1.358 djm 1100: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1101: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1102: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1103: sshbuf_len(c->extended) > 0)
1.44 markus 1104: FD_SET(c->efd, writeset);
1.306 djm 1105: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1106: (c->extended_usage == CHAN_EXTENDED_READ ||
1107: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1108: sshbuf_len(c->extended) < c->remote_window)
1.44 markus 1109: FD_SET(c->efd, readset);
1110: }
1.204 djm 1111: /* XXX: What about efd? races? */
1.44 markus 1112: }
1113:
1.41 markus 1114: /*
1115: * This is a special state for X11 authentication spoofing. An opened X11
1116: * connection (when authentication spoofing is being done) remains in this
1117: * state until the first packet has been completely read. The authentication
1118: * data in that packet is then substituted by the real data if it matches the
1119: * fake data, and the channel is put into normal mode.
1.51 markus 1120: * XXX All this happens at the client side.
1.121 markus 1121: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1122: */
1.127 itojun 1123: static int
1.367 djm 1124: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1125: {
1.367 djm 1126: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1127: u_char *ucp;
1128: u_int proto_len, data_len;
1.25 markus 1129:
1.347 djm 1130: /* Is this being called after the refusal deadline? */
1.367 djm 1131: if (sc->x11_refuse_time != 0 &&
1132: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1133: verbose("Rejected X11 connection after ForwardX11Timeout "
1134: "expired");
1135: return -1;
1136: }
1137:
1.41 markus 1138: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1139: if (sshbuf_len(b) < 12)
1.41 markus 1140: return 0;
1141:
1142: /* Parse the lengths of variable-length fields. */
1.367 djm 1143: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1144: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1145: proto_len = 256 * ucp[6] + ucp[7];
1146: data_len = 256 * ucp[8] + ucp[9];
1147: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1148: proto_len = ucp[6] + 256 * ucp[7];
1149: data_len = ucp[8] + 256 * ucp[9];
1150: } else {
1.194 markus 1151: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1152: ucp[0]);
1.41 markus 1153: return -1;
1154: }
1155:
1156: /* Check if the whole packet is in buffer. */
1.367 djm 1157: if (sshbuf_len(b) <
1.41 markus 1158: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1159: return 0;
1160:
1161: /* Check if authentication protocol matches. */
1.367 djm 1162: if (proto_len != strlen(sc->x11_saved_proto) ||
1163: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1164: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1165: return -1;
1166: }
1167: /* Check if authentication data matches our fake data. */
1.367 djm 1168: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1169: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1170: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1171: debug2("X11 auth data does not match fake data.");
1.41 markus 1172: return -1;
1173: }
1174: /* Check fake data length */
1.367 djm 1175: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1176: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1177: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1178: return -1;
1179: }
1180: /*
1181: * Received authentication protocol and data match
1182: * our fake data. Substitute the fake data with real
1183: * data.
1184: */
1185: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1186: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1187: return 1;
1188: }
1189:
1.127 itojun 1190: static void
1.367 djm 1191: channel_pre_x11_open(struct ssh *ssh, Channel *c,
1192: fd_set *readset, fd_set *writeset)
1.41 markus 1193: {
1.367 djm 1194: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1195:
1196: /* c->force_drain = 1; */
1197:
1.41 markus 1198: if (ret == 1) {
1199: c->type = SSH_CHANNEL_OPEN;
1.367 djm 1200: channel_pre_open(ssh, c, readset, writeset);
1.41 markus 1201: } else if (ret == -1) {
1.188 itojun 1202: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1203: debug2("X11 rejected %d i%d/o%d",
1204: c->self, c->istate, c->ostate);
1205: chan_read_failed(ssh, c);
1206: sshbuf_reset(c->input);
1207: chan_ibuf_empty(ssh, c);
1208: sshbuf_reset(c->output);
1209: chan_write_failed(ssh, c);
1.194 markus 1210: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1211: }
1212: }
1.25 markus 1213:
1.302 djm 1214: static void
1.367 djm 1215: channel_pre_mux_client(struct ssh *ssh,
1216: Channel *c, fd_set *readset, fd_set *writeset)
1.302 djm 1217: {
1.304 djm 1218: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1219: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.302 djm 1220: FD_SET(c->rfd, readset);
1221: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1222: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1223: sshbuf_reset(c->input);
1224: chan_ibuf_empty(ssh, c);
1.302 djm 1225: /* Start output drain. XXX just kill chan? */
1.367 djm 1226: chan_rcvd_oclose(ssh, c);
1.302 djm 1227: }
1228: if (c->ostate == CHAN_OUTPUT_OPEN ||
1229: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1230: if (sshbuf_len(c->output) > 0)
1.302 djm 1231: FD_SET(c->wfd, writeset);
1232: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1233: chan_obuf_empty(ssh, c);
1.302 djm 1234: }
1235: }
1236:
1.104 markus 1237: /* try to decode a socks4 header */
1.127 itojun 1238: static int
1.372 markus 1239: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1240: {
1.367 djm 1241: const u_char *p;
1242: char *host;
1.292 djm 1243: u_int len, have, i, found, need;
1.148 deraadt 1244: char username[256];
1.103 markus 1245: struct {
1246: u_int8_t version;
1247: u_int8_t command;
1248: u_int16_t dest_port;
1.104 markus 1249: struct in_addr dest_addr;
1.103 markus 1250: } s4_req, s4_rsp;
1.367 djm 1251: int r;
1.103 markus 1252:
1.104 markus 1253: debug2("channel %d: decode socks4", c->self);
1.109 markus 1254:
1.372 markus 1255: have = sshbuf_len(input);
1.109 markus 1256: len = sizeof(s4_req);
1257: if (have < len)
1258: return 0;
1.372 markus 1259: p = sshbuf_ptr(input);
1.292 djm 1260:
1261: need = 1;
1262: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1263: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1264: debug2("channel %d: socks4a request", c->self);
1265: /* ... and needs an extra string (the hostname) */
1266: need = 2;
1267: }
1268: /* Check for terminating NUL on the string(s) */
1.109 markus 1269: for (found = 0, i = len; i < have; i++) {
1270: if (p[i] == '\0') {
1.292 djm 1271: found++;
1272: if (found == need)
1273: break;
1.109 markus 1274: }
1275: if (i > 1024) {
1276: /* the peer is probably sending garbage */
1277: debug("channel %d: decode socks4: too long",
1278: c->self);
1279: return -1;
1280: }
1281: }
1.292 djm 1282: if (found < need)
1.109 markus 1283: return 0;
1.372 markus 1284: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1285: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1286: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1287: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.367 djm 1288: debug("channels %d: decode socks4: %s", c->self, ssh_err(r));
1289: return -1;
1290: }
1.372 markus 1291: have = sshbuf_len(input);
1292: p = sshbuf_ptr(input);
1.364 djm 1293: if (memchr(p, '\0', have) == NULL) {
1294: error("channel %d: decode socks4: user not nul terminated",
1.331 djm 1295: c->self);
1.364 djm 1296: return -1;
1297: }
1.103 markus 1298: len = strlen(p);
1.106 markus 1299: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1300: len++; /* trailing '\0' */
1.103 markus 1301: strlcpy(username, p, sizeof(username));
1.372 markus 1302: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1303: fatal("%s: channel %d: consume: %s", __func__,
1304: c->self, ssh_err(r));
1305: }
1.321 djm 1306: free(c->path);
1307: c->path = NULL;
1.292 djm 1308: if (need == 1) { /* SOCKS4: one string */
1309: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1310: c->path = xstrdup(host);
1.292 djm 1311: } else { /* SOCKS4A: two strings */
1.372 markus 1312: have = sshbuf_len(input);
1313: p = sshbuf_ptr(input);
1.364 djm 1314: if (memchr(p, '\0', have) == NULL) {
1315: error("channel %d: decode socks4a: host not nul "
1316: "terminated", c->self);
1317: return -1;
1318: }
1.292 djm 1319: len = strlen(p);
1320: debug2("channel %d: decode socks4a: host %s/%d",
1321: c->self, p, len);
1322: len++; /* trailing '\0' */
1.293 djm 1323: if (len > NI_MAXHOST) {
1.292 djm 1324: error("channel %d: hostname \"%.100s\" too long",
1325: c->self, p);
1326: return -1;
1327: }
1.293 djm 1328: c->path = xstrdup(p);
1.372 markus 1329: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1330: fatal("%s: channel %d: consume: %s", __func__,
1331: c->self, ssh_err(r));
1332: }
1.292 djm 1333: }
1.103 markus 1334: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1335:
1.194 markus 1336: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1337: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1338:
1.104 markus 1339: if (s4_req.command != 1) {
1.292 djm 1340: debug("channel %d: cannot handle: %s cn %d",
1341: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1342: return -1;
1.103 markus 1343: }
1.104 markus 1344: s4_rsp.version = 0; /* vn: 0 for reply */
1345: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1346: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1347: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.372 markus 1348: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0) {
1.367 djm 1349: fatal("%s: channel %d: append reply: %s", __func__,
1350: c->self, ssh_err(r));
1351: }
1.104 markus 1352: return 1;
1353: }
1354:
1.193 markus 1355: /* try to decode a socks5 header */
1356: #define SSH_SOCKS5_AUTHDONE 0x1000
1357: #define SSH_SOCKS5_NOAUTH 0x00
1358: #define SSH_SOCKS5_IPV4 0x01
1359: #define SSH_SOCKS5_DOMAIN 0x03
1360: #define SSH_SOCKS5_IPV6 0x04
1361: #define SSH_SOCKS5_CONNECT 0x01
1362: #define SSH_SOCKS5_SUCCESS 0x00
1363:
1364: static int
1.372 markus 1365: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1366: {
1.367 djm 1367: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1368: struct {
1369: u_int8_t version;
1370: u_int8_t command;
1371: u_int8_t reserved;
1372: u_int8_t atyp;
1373: } s5_req, s5_rsp;
1374: u_int16_t dest_port;
1.324 djm 1375: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1376: const u_char *p;
1.252 djm 1377: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1378: int r;
1.193 markus 1379:
1380: debug2("channel %d: decode socks5", c->self);
1.372 markus 1381: p = sshbuf_ptr(input);
1.193 markus 1382: if (p[0] != 0x05)
1383: return -1;
1.372 markus 1384: have = sshbuf_len(input);
1.193 markus 1385: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1386: /* format: ver | nmethods | methods */
1.198 djm 1387: if (have < 2)
1.193 markus 1388: return 0;
1389: nmethods = p[1];
1390: if (have < nmethods + 2)
1391: return 0;
1392: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1393: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1394: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1395: found = 1;
1396: break;
1397: }
1398: }
1399: if (!found) {
1400: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1401: c->self);
1402: return -1;
1403: }
1.372 markus 1404: if ((r = sshbuf_consume(input, nmethods + 2)) != 0) {
1.367 djm 1405: fatal("%s: channel %d: consume: %s", __func__,
1406: c->self, ssh_err(r));
1407: }
1408: /* version, method */
1.372 markus 1409: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1410: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0) {
1.367 djm 1411: fatal("%s: channel %d: append reply: %s", __func__,
1412: c->self, ssh_err(r));
1413: }
1.193 markus 1414: c->flags |= SSH_SOCKS5_AUTHDONE;
1415: debug2("channel %d: socks5 auth done", c->self);
1416: return 0; /* need more */
1417: }
1418: debug2("channel %d: socks5 post auth", c->self);
1419: if (have < sizeof(s5_req)+1)
1420: return 0; /* need more */
1.247 deraadt 1421: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1422: if (s5_req.version != 0x05 ||
1423: s5_req.command != SSH_SOCKS5_CONNECT ||
1424: s5_req.reserved != 0x00) {
1.194 markus 1425: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1426: return -1;
1427: }
1.213 deraadt 1428: switch (s5_req.atyp){
1.193 markus 1429: case SSH_SOCKS5_IPV4:
1430: addrlen = 4;
1431: af = AF_INET;
1432: break;
1433: case SSH_SOCKS5_DOMAIN:
1434: addrlen = p[sizeof(s5_req)];
1435: af = -1;
1436: break;
1437: case SSH_SOCKS5_IPV6:
1438: addrlen = 16;
1439: af = AF_INET6;
1440: break;
1441: default:
1.194 markus 1442: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1443: return -1;
1444: }
1.252 djm 1445: need = sizeof(s5_req) + addrlen + 2;
1446: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1447: need++;
1448: if (have < need)
1.193 markus 1449: return 0;
1.372 markus 1450: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0) {
1.367 djm 1451: fatal("%s: channel %d: consume: %s", __func__,
1452: c->self, ssh_err(r));
1453: }
1454: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1455: /* host string length */
1.372 markus 1456: if ((r = sshbuf_consume(input, 1)) != 0) {
1.367 djm 1457: fatal("%s: channel %d: consume: %s", __func__,
1458: c->self, ssh_err(r));
1459: }
1460: }
1.372 markus 1461: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1462: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.367 djm 1463: debug("channel %d: parse addr/port: %s", c->self, ssh_err(r));
1464: return -1;
1465: }
1.193 markus 1466: dest_addr[addrlen] = '\0';
1.321 djm 1467: free(c->path);
1468: c->path = NULL;
1.293 djm 1469: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1470: if (addrlen >= NI_MAXHOST) {
1.293 djm 1471: error("channel %d: dynamic request: socks5 hostname "
1472: "\"%.100s\" too long", c->self, dest_addr);
1473: return -1;
1474: }
1475: c->path = xstrdup(dest_addr);
1476: } else {
1477: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1478: return -1;
1479: c->path = xstrdup(ntop);
1480: }
1.193 markus 1481: c->host_port = ntohs(dest_port);
1.198 djm 1482:
1.194 markus 1483: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1484: c->self, c->path, c->host_port, s5_req.command);
1485:
1486: s5_rsp.version = 0x05;
1487: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1488: s5_rsp.reserved = 0; /* ignored */
1489: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1490: dest_port = 0; /* ignored */
1491:
1.372 markus 1492: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1493: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1494: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.367 djm 1495: fatal("%s: channel %d: append reply: %s", __func__,
1496: c->self, ssh_err(r));
1.193 markus 1497: return 1;
1.301 dtucker 1498: }
1499:
1500: Channel *
1.367 djm 1501: channel_connect_stdio_fwd(struct ssh *ssh,
1502: const char *host_to_connect, u_short port_to_connect, int in, int out)
1.301 dtucker 1503: {
1504: Channel *c;
1505:
1.367 djm 1506: debug("%s %s:%d", __func__, host_to_connect, port_to_connect);
1.301 dtucker 1507:
1.367 djm 1508: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1509: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1510: 0, "stdio-forward", /*nonblock*/0);
1511:
1512: c->path = xstrdup(host_to_connect);
1513: c->host_port = port_to_connect;
1514: c->listening_port = 0;
1515: c->force_drain = 1;
1516:
1.367 djm 1517: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1518: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1519:
1520: return c;
1.193 markus 1521: }
1522:
1.104 markus 1523: /* dynamic port forwarding */
1.127 itojun 1524: static void
1.367 djm 1525: channel_pre_dynamic(struct ssh *ssh, Channel *c,
1526: fd_set *readset, fd_set *writeset)
1.104 markus 1527: {
1.367 djm 1528: const u_char *p;
1.217 djm 1529: u_int have;
1530: int ret;
1.103 markus 1531:
1.367 djm 1532: have = sshbuf_len(c->input);
1.104 markus 1533: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1534: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1535: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1536: if (have < 3) {
1.104 markus 1537: /* need more */
1538: FD_SET(c->sock, readset);
1539: return;
1540: }
1541: /* try to guess the protocol */
1.367 djm 1542: p = sshbuf_ptr(c->input);
1543: /* XXX sshbuf_peek_u8? */
1.104 markus 1544: switch (p[0]) {
1545: case 0x04:
1.372 markus 1546: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1547: break;
1548: case 0x05:
1.372 markus 1549: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1550: break;
1551: default:
1552: ret = -1;
1553: break;
1554: }
1555: if (ret < 0) {
1.367 djm 1556: chan_mark_dead(ssh, c);
1.104 markus 1557: } else if (ret == 0) {
1558: debug2("channel %d: pre_dynamic: need more", c->self);
1559: /* need more */
1560: FD_SET(c->sock, readset);
1.372 markus 1561: if (sshbuf_len(c->output))
1562: FD_SET(c->sock, writeset);
1.104 markus 1563: } else {
1564: /* switch to the next state */
1565: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1566: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1567: }
1.103 markus 1568: }
1569:
1.372 markus 1570: /* simulate read-error */
1571: static void
1572: rdynamic_close(struct ssh *ssh, Channel *c)
1573: {
1574: c->type = SSH_CHANNEL_OPEN;
1575: chan_read_failed(ssh, c);
1576: sshbuf_reset(c->input);
1577: chan_ibuf_empty(ssh, c);
1578: sshbuf_reset(c->output);
1579: chan_write_failed(ssh, c);
1580: }
1581:
1582: /* reverse dynamic port forwarding */
1583: static void
1584: channel_before_prepare_select_rdynamic(struct ssh *ssh, Channel *c)
1585: {
1586: const u_char *p;
1587: u_int have, len;
1588: int r, ret;
1589:
1590: have = sshbuf_len(c->output);
1591: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1592: /* sshbuf_dump(c->output, stderr); */
1593: /* EOF received */
1594: if (c->flags & CHAN_EOF_RCVD) {
1595: if ((r = sshbuf_consume(c->output, have)) != 0) {
1596: fatal("%s: channel %d: consume: %s",
1597: __func__, c->self, ssh_err(r));
1598: }
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) {
1630: fatal("%s: channel %i: rdynamic: %s", __func__,
1631: c->self, ssh_err(r));
1632: }
1633: if ((r = sshbuf_consume(c->input, len)) != 0) {
1634: fatal("%s: channel %d: consume: %s",
1635: __func__, c->self, ssh_err(r));
1636: }
1637: c->remote_window -= len;
1638: }
1639: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1640: /* the connect failed */
1641: rdynamic_close(ssh, c);
1642: }
1643: }
1644:
1.41 markus 1645: /* This is our fake X11 server socket. */
1.127 itojun 1646: static void
1.367 djm 1647: channel_post_x11_listener(struct ssh *ssh, Channel *c,
1648: fd_set *readset, fd_set *writeset)
1.41 markus 1649: {
1.113 markus 1650: Channel *nc;
1.285 djm 1651: struct sockaddr_storage addr;
1.367 djm 1652: int r, newsock, oerrno, remote_port;
1.41 markus 1653: socklen_t addrlen;
1.85 markus 1654: char buf[16384], *remote_ipaddr;
1.25 markus 1655:
1.367 djm 1656: if (!FD_ISSET(c->sock, readset))
1657: return;
1658:
1659: debug("X11 connection requested.");
1660: addrlen = sizeof(addr);
1661: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1662: if (c->single_connection) {
1663: oerrno = errno;
1664: debug2("single_connection: closing X11 listener.");
1665: channel_close_fd(ssh, &c->sock);
1666: chan_mark_dead(ssh, c);
1667: errno = oerrno;
1668: }
1.393 deraadt 1669: if (newsock == -1) {
1.367 djm 1670: if (errno != EINTR && errno != EWOULDBLOCK &&
1671: errno != ECONNABORTED)
1672: error("accept: %.100s", strerror(errno));
1673: if (errno == EMFILE || errno == ENFILE)
1674: c->notbefore = monotime() + 1;
1675: return;
1676: }
1677: set_nodelay(newsock);
1678: remote_ipaddr = get_peer_ipaddr(newsock);
1679: remote_port = get_peer_port(newsock);
1680: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1681: remote_ipaddr, remote_port);
1682:
1683: nc = channel_new(ssh, "accepted x11 socket",
1684: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1685: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1686: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1687: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1688: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.367 djm 1689: fatal("%s: channel %i: reply %s", __func__,
1690: c->self, ssh_err(r));
1.41 markus 1691: }
1.367 djm 1692: if ((r = sshpkt_send(ssh)) != 0)
1693: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1694: free(remote_ipaddr);
1.41 markus 1695: }
1.25 markus 1696:
1.127 itojun 1697: static void
1.367 djm 1698: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1699: {
1.328 djm 1700: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1701: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1702: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1703: int remote_port = get_peer_port(c->sock);
1.367 djm 1704: int r;
1.303 djm 1705:
1706: if (remote_port == -1) {
1707: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1708: free(remote_ipaddr);
1.303 djm 1709: remote_ipaddr = xstrdup("127.0.0.1");
1710: remote_port = 65535;
1711: }
1.103 markus 1712:
1.367 djm 1713: free(c->remote_name);
1714: xasprintf(&c->remote_name,
1.103 markus 1715: "%s: listening port %d for %.100s port %d, "
1.328 djm 1716: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1717: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1718: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1719:
1.367 djm 1720: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1721: if (strcmp(rtype, "direct-tcpip") == 0) {
1722: /* target host, port */
1.367 djm 1723: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1724: (r = sshpkt_put_u32(ssh, c->host_port)) != 0) {
1725: fatal("%s: channel %i: reply %s", __func__,
1726: c->self, ssh_err(r));
1727: }
1.358 djm 1728: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1729: /* target path */
1.367 djm 1730: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1731: fatal("%s: channel %i: reply %s", __func__,
1732: c->self, ssh_err(r));
1733: }
1.358 djm 1734: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1735: /* listen path */
1.367 djm 1736: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1737: fatal("%s: channel %i: reply %s", __func__,
1738: c->self, ssh_err(r));
1739: }
1.103 markus 1740: } else {
1.358 djm 1741: /* listen address, port */
1.367 djm 1742: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1743: (r = sshpkt_put_u32(ssh, local_port)) != 0) {
1744: fatal("%s: channel %i: reply %s", __func__,
1745: c->self, ssh_err(r));
1746: }
1.358 djm 1747: }
1748: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1749: /* reserved for future owner/mode info */
1.367 djm 1750: if ((r = sshpkt_put_cstring(ssh, "")) != 0) {
1751: fatal("%s: channel %i: reply %s", __func__,
1752: c->self, ssh_err(r));
1753: }
1.358 djm 1754: } else {
1755: /* originator host and port */
1.367 djm 1756: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1757: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0) {
1758: fatal("%s: channel %i: reply %s", __func__,
1759: c->self, ssh_err(r));
1760: }
1.103 markus 1761: }
1.367 djm 1762: if ((r = sshpkt_send(ssh)) != 0)
1763: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1.321 djm 1764: free(remote_ipaddr);
1.328 djm 1765: free(local_ipaddr);
1.103 markus 1766: }
1767:
1.347 djm 1768: void
1.367 djm 1769: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1770: {
1.367 djm 1771: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1772: }
1773:
1.41 markus 1774: /*
1775: * This socket is listening for connections to a forwarded TCP/IP port.
1776: */
1.127 itojun 1777: static void
1.367 djm 1778: channel_post_port_listener(struct ssh *ssh, Channel *c,
1779: fd_set *readset, fd_set *writeset)
1.41 markus 1780: {
1.103 markus 1781: Channel *nc;
1.285 djm 1782: struct sockaddr_storage addr;
1.113 markus 1783: int newsock, nextstate;
1.41 markus 1784: socklen_t addrlen;
1.103 markus 1785: char *rtype;
1.73 markus 1786:
1.367 djm 1787: if (!FD_ISSET(c->sock, readset))
1788: return;
1789:
1790: debug("Connection to port %d forwarding to %.100s port %d requested.",
1791: c->listening_port, c->path, c->host_port);
1.103 markus 1792:
1.367 djm 1793: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1794: nextstate = SSH_CHANNEL_OPENING;
1795: rtype = "forwarded-tcpip";
1796: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1797: nextstate = SSH_CHANNEL_OPENING;
1798: rtype = "forwarded-streamlocal@openssh.com";
1799: } else if (c->host_port == PORT_STREAMLOCAL) {
1800: nextstate = SSH_CHANNEL_OPENING;
1801: rtype = "direct-streamlocal@openssh.com";
1802: } else if (c->host_port == 0) {
1803: nextstate = SSH_CHANNEL_DYNAMIC;
1804: rtype = "dynamic-tcpip";
1805: } else {
1806: nextstate = SSH_CHANNEL_OPENING;
1807: rtype = "direct-tcpip";
1808: }
1.103 markus 1809:
1.367 djm 1810: addrlen = sizeof(addr);
1811: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1812: if (newsock == -1) {
1.367 djm 1813: if (errno != EINTR && errno != EWOULDBLOCK &&
1814: errno != ECONNABORTED)
1815: error("accept: %.100s", strerror(errno));
1816: if (errno == EMFILE || errno == ENFILE)
1817: c->notbefore = monotime() + 1;
1818: return;
1.41 markus 1819: }
1.367 djm 1820: if (c->host_port != PORT_STREAMLOCAL)
1821: set_nodelay(newsock);
1822: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1823: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1824: nc->listening_port = c->listening_port;
1825: nc->host_port = c->host_port;
1826: if (c->path != NULL)
1827: nc->path = xstrdup(c->path);
1828:
1829: if (nextstate != SSH_CHANNEL_DYNAMIC)
1830: port_open_helper(ssh, nc, rtype);
1.41 markus 1831: }
1.25 markus 1832:
1.41 markus 1833: /*
1834: * This is the authentication agent socket listening for connections from
1835: * clients.
1836: */
1.127 itojun 1837: static void
1.367 djm 1838: channel_post_auth_listener(struct ssh *ssh, Channel *c,
1839: fd_set *readset, fd_set *writeset)
1.41 markus 1840: {
1.113 markus 1841: Channel *nc;
1.367 djm 1842: int r, newsock;
1.285 djm 1843: struct sockaddr_storage addr;
1.41 markus 1844: socklen_t addrlen;
1.25 markus 1845:
1.367 djm 1846: if (!FD_ISSET(c->sock, readset))
1847: return;
1848:
1849: addrlen = sizeof(addr);
1850: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1851: if (newsock == -1) {
1.367 djm 1852: error("accept from auth socket: %.100s", strerror(errno));
1853: if (errno == EMFILE || errno == ENFILE)
1854: c->notbefore = monotime() + 1;
1855: return;
1.41 markus 1856: }
1.367 djm 1857: nc = channel_new(ssh, "accepted auth socket",
1858: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1859: c->local_window_max, c->local_maxpacket,
1860: 0, "accepted auth socket", 1);
1861: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1862: if ((r = sshpkt_send(ssh)) != 0)
1863: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.41 markus 1864: }
1.25 markus 1865:
1.127 itojun 1866: static void
1.367 djm 1867: channel_post_connecting(struct ssh *ssh, Channel *c,
1868: fd_set *readset, fd_set *writeset)
1.75 markus 1869: {
1.372 markus 1870: int err = 0, sock, isopen, r;
1.129 stevesk 1871: socklen_t sz = sizeof(err);
1.114 markus 1872:
1.367 djm 1873: if (!FD_ISSET(c->sock, writeset))
1874: return;
1.368 djm 1875: if (!c->have_remote_id)
1876: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.372 markus 1877: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1878: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.393 deraadt 1879: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 1880: err = errno;
1881: error("getsockopt SO_ERROR failed");
1882: }
1883: if (err == 0) {
1884: debug("channel %d: connected to %s port %d",
1885: c->self, c->connect_ctx.host, c->connect_ctx.port);
1886: channel_connect_ctx_free(&c->connect_ctx);
1887: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1888: if (isopen) {
1889: /* no message necessary */
1890: } else {
1891: if ((r = sshpkt_start(ssh,
1892: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1893: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1894: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1895: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1896: (r = sshpkt_put_u32(ssh, c->local_maxpacket))
1897: != 0)
1898: fatal("%s: channel %i: confirm: %s", __func__,
1899: c->self, ssh_err(r));
1900: if ((r = sshpkt_send(ssh)) != 0)
1901: fatal("%s: channel %i: %s", __func__, c->self,
1902: ssh_err(r));
1.367 djm 1903: }
1904: } else {
1905: debug("channel %d: connection failed: %s",
1906: c->self, strerror(err));
1907: /* Try next address, if any */
1908: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1909: close(c->sock);
1910: c->sock = c->rfd = c->wfd = sock;
1911: channel_find_maxfd(ssh->chanctxt);
1912: return;
1913: }
1914: /* Exhausted all addresses */
1915: error("connect_to %.100s port %d: failed.",
1916: c->connect_ctx.host, c->connect_ctx.port);
1917: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1918: if (isopen) {
1919: rdynamic_close(ssh, c);
1920: } else {
1921: if ((r = sshpkt_start(ssh,
1922: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1923: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 1924: (r = sshpkt_put_u32(ssh,
1925: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
1926: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1927: (r = sshpkt_put_cstring(ssh, "")) != 0) {
1.372 markus 1928: fatal("%s: channel %i: failure: %s", __func__,
1929: c->self, ssh_err(r));
1.378 djm 1930: }
1.372 markus 1931: if ((r = sshpkt_send(ssh)) != 0)
1932: fatal("%s: channel %i: %s", __func__, c->self,
1933: ssh_err(r));
1934: chan_mark_dead(ssh, c);
1.75 markus 1935: }
1936: }
1937: }
1938:
1.127 itojun 1939: static int
1.367 djm 1940: channel_handle_rfd(struct ssh *ssh, Channel *c,
1941: fd_set *readset, fd_set *writeset)
1.41 markus 1942: {
1.214 markus 1943: char buf[CHAN_RBUF];
1.367 djm 1944: ssize_t len;
1945: int r;
1.25 markus 1946:
1.367 djm 1947: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
1948: return 1;
1949:
1950: len = read(c->rfd, buf, sizeof(buf));
1.393 deraadt 1951: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 1952: return 1;
1953: if (len <= 0) {
1954: debug2("channel %d: read<=0 rfd %d len %zd",
1955: c->self, c->rfd, len);
1956: if (c->type != SSH_CHANNEL_OPEN) {
1957: debug2("channel %d: not open", c->self);
1958: chan_mark_dead(ssh, c);
1.41 markus 1959: return -1;
1.65 markus 1960: } else {
1.367 djm 1961: chan_read_failed(ssh, c);
1.65 markus 1962: }
1.367 djm 1963: return -1;
1964: }
1965: if (c->input_filter != NULL) {
1966: if (c->input_filter(ssh, c, buf, len) == -1) {
1967: debug2("channel %d: filter stops", c->self);
1968: chan_read_failed(ssh, c);
1969: }
1970: } else if (c->datagram) {
1971: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1972: fatal("%s: channel %d: put datagram: %s", __func__,
1973: c->self, ssh_err(r));
1974: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
1975: fatal("%s: channel %d: put data: %s", __func__,
1976: c->self, ssh_err(r));
1.41 markus 1977: }
1978: return 1;
1979: }
1.241 deraadt 1980:
1.127 itojun 1981: static int
1.367 djm 1982: channel_handle_wfd(struct ssh *ssh, Channel *c,
1983: fd_set *readset, fd_set *writeset)
1.41 markus 1984: {
1.95 markus 1985: struct termios tio;
1.367 djm 1986: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1987: size_t dlen, olen = 0;
1988: int r, len;
1989:
1990: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
1991: sshbuf_len(c->output) == 0)
1992: return 1;
1.25 markus 1993:
1.41 markus 1994: /* Send buffered output data to the socket. */
1.367 djm 1995: olen = sshbuf_len(c->output);
1996: if (c->output_filter != NULL) {
1997: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1998: debug2("channel %d: filter stops", c->self);
1999: if (c->type != SSH_CHANNEL_OPEN)
2000: chan_mark_dead(ssh, c);
2001: else
2002: chan_write_failed(ssh, c);
2003: return -1;
1.231 reyk 2004: }
1.367 djm 2005: } else if (c->datagram) {
2006: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
2007: fatal("%s: channel %d: get datagram: %s", __func__,
2008: c->self, ssh_err(r));
1.369 djm 2009: buf = data;
1.367 djm 2010: } else {
2011: buf = data = sshbuf_mutable_ptr(c->output);
2012: dlen = sshbuf_len(c->output);
2013: }
1.231 reyk 2014:
1.367 djm 2015: if (c->datagram) {
2016: /* ignore truncated writes, datagrams might get lost */
1.374 djm 2017: len = write(c->wfd, buf, dlen);
1.367 djm 2018: free(data);
1.393 deraadt 2019: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 2020: return 1;
1.367 djm 2021: if (len <= 0)
2022: goto write_fail;
2023: goto out;
2024: }
2025:
2026: len = write(c->wfd, buf, dlen);
1.393 deraadt 2027: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2028: return 1;
2029: if (len <= 0) {
2030: write_fail:
2031: if (c->type != SSH_CHANNEL_OPEN) {
2032: debug2("channel %d: not open", c->self);
2033: chan_mark_dead(ssh, c);
1.41 markus 2034: return -1;
1.367 djm 2035: } else {
2036: chan_write_failed(ssh, c);
1.91 markus 2037: }
1.367 djm 2038: return -1;
2039: }
2040: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2041: if (tcgetattr(c->wfd, &tio) == 0 &&
2042: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2043: /*
2044: * Simulate echo to reduce the impact of
2045: * traffic analysis. We need to match the
2046: * size of a SSH2_MSG_CHANNEL_DATA message
2047: * (4 byte channel id + buf)
2048: */
2049: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2050: (r = sshpkt_send(ssh)) != 0)
2051: fatal("%s: channel %d: ignore: %s",
2052: __func__, c->self, ssh_err(r));
1.25 markus 2053: }
1.367 djm 2054: }
2055: if ((r = sshbuf_consume(c->output, len)) != 0) {
2056: fatal("%s: channel %d: consume: %s",
2057: __func__, c->self, ssh_err(r));
1.44 markus 2058: }
1.309 djm 2059: out:
1.367 djm 2060: c->local_consumed += olen - sshbuf_len(c->output);
2061:
2062: return 1;
2063: }
2064:
2065: static int
2066: channel_handle_efd_write(struct ssh *ssh, Channel *c,
2067: fd_set *readset, fd_set *writeset)
2068: {
2069: int r;
2070: ssize_t len;
2071:
2072: if (!FD_ISSET(c->efd, writeset) || sshbuf_len(c->extended) == 0)
2073: return 1;
2074:
2075: len = write(c->efd, sshbuf_ptr(c->extended),
2076: sshbuf_len(c->extended));
2077: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 deraadt 2078: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2079: return 1;
2080: if (len <= 0) {
2081: debug2("channel %d: closing write-efd %d", c->self, c->efd);
2082: channel_close_fd(ssh, &c->efd);
2083: } else {
2084: if ((r = sshbuf_consume(c->extended, len)) != 0) {
2085: fatal("%s: channel %d: consume: %s",
2086: __func__, c->self, ssh_err(r));
2087: }
2088: c->local_consumed += len;
2089: }
1.44 markus 2090: return 1;
2091: }
1.241 deraadt 2092:
1.127 itojun 2093: static int
1.367 djm 2094: channel_handle_efd_read(struct ssh *ssh, Channel *c,
2095: fd_set *readset, fd_set *writeset)
1.44 markus 2096: {
1.214 markus 2097: char buf[CHAN_RBUF];
1.367 djm 2098: int r;
2099: ssize_t len;
2100:
2101: if (!FD_ISSET(c->efd, readset))
2102: return 1;
1.44 markus 2103:
1.367 djm 2104: len = read(c->efd, buf, sizeof(buf));
2105: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 deraadt 2106: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2107: return 1;
2108: if (len <= 0) {
2109: debug2("channel %d: closing read-efd %d",
2110: c->self, c->efd);
2111: channel_close_fd(ssh, &c->efd);
2112: } else {
2113: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
2114: debug3("channel %d: discard efd",
2115: c->self);
2116: } else if ((r = sshbuf_put(c->extended, buf, len)) != 0) {
2117: fatal("%s: channel %d: append: %s",
2118: __func__, c->self, ssh_err(r));
1.44 markus 2119: }
2120: }
2121: return 1;
2122: }
1.241 deraadt 2123:
1.127 itojun 2124: static int
1.367 djm 2125: channel_handle_efd(struct ssh *ssh, Channel *c,
2126: fd_set *readset, fd_set *writeset)
1.44 markus 2127: {
1.367 djm 2128: if (c->efd == -1)
2129: return 1;
2130:
2131: /** XXX handle drain efd, too */
2132:
2133: if (c->extended_usage == CHAN_EXTENDED_WRITE)
2134: return channel_handle_efd_write(ssh, c, readset, writeset);
2135: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2136: c->extended_usage == CHAN_EXTENDED_IGNORE)
2137: return channel_handle_efd_read(ssh, c, readset, writeset);
2138:
2139: return 1;
2140: }
2141:
2142: static int
2143: channel_check_window(struct ssh *ssh, Channel *c)
2144: {
2145: int r;
2146:
1.104 markus 2147: if (c->type == SSH_CHANNEL_OPEN &&
2148: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2149: ((c->local_window_max - c->local_window >
1.269 markus 2150: c->local_maxpacket*3) ||
2151: c->local_window < c->local_window_max/2) &&
1.44 markus 2152: c->local_consumed > 0) {
1.368 djm 2153: if (!c->have_remote_id)
2154: fatal(":%s: channel %d: no remote id",
2155: __func__, c->self);
1.367 djm 2156: if ((r = sshpkt_start(ssh,
2157: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2158: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2159: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2160: (r = sshpkt_send(ssh)) != 0) {
2161: fatal("%s: channel %i: %s", __func__,
2162: c->self, ssh_err(r));
2163: }
1.70 markus 2164: debug2("channel %d: window %d sent adjust %d",
1.44 markus 2165: c->self, c->local_window,
2166: c->local_consumed);
2167: c->local_window += c->local_consumed;
2168: c->local_consumed = 0;
1.1 deraadt 2169: }
1.41 markus 2170: return 1;
1.1 deraadt 2171: }
2172:
1.127 itojun 2173: static void
1.367 djm 2174: channel_post_open(struct ssh *ssh, Channel *c,
2175: fd_set *readset, fd_set *writeset)
1.41 markus 2176: {
1.367 djm 2177: channel_handle_rfd(ssh, c, readset, writeset);
2178: channel_handle_wfd(ssh, c, readset, writeset);
2179: channel_handle_efd(ssh, c, readset, writeset);
2180: channel_check_window(ssh, c);
1.44 markus 2181: }
2182:
1.302 djm 2183: static u_int
1.367 djm 2184: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2185: {
2186: char buf[CHAN_RBUF];
1.367 djm 2187: ssize_t len;
1.302 djm 2188: u_int rlen;
1.367 djm 2189: int r;
1.302 djm 2190:
1.367 djm 2191: if (sshbuf_len(c->input) < need) {
2192: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2193: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 deraadt 2194: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2195: return sshbuf_len(c->input);
1.302 djm 2196: if (len <= 0) {
1.367 djm 2197: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2198: c->self, c->rfd, len);
1.367 djm 2199: chan_read_failed(ssh, c);
1.349 naddy 2200: return 0;
1.367 djm 2201: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
2202: fatal("%s: channel %d: append: %s",
2203: __func__, c->self, ssh_err(r));
2204: }
1.302 djm 2205: }
1.367 djm 2206: return sshbuf_len(c->input);
1.302 djm 2207: }
2208:
2209: static void
1.367 djm 2210: channel_post_mux_client_read(struct ssh *ssh, Channel *c,
2211: fd_set *readset, fd_set *writeset)
1.302 djm 2212: {
2213: u_int need;
2214:
1.367 djm 2215: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
2216: return;
2217: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2218: return;
2219: if (c->mux_pause)
2220: return;
2221:
2222: /*
2223: * Don't not read past the precise end of packets to
2224: * avoid disrupting fd passing.
2225: */
2226: if (read_mux(ssh, c, 4) < 4) /* read header */
2227: return;
2228: /* XXX sshbuf_peek_u32 */
2229: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2230: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2231: if (need > CHANNEL_MUX_MAX_PACKET) {
2232: debug2("channel %d: packet too big %u > %u",
2233: c->self, CHANNEL_MUX_MAX_PACKET, need);
2234: chan_rcvd_oclose(ssh, c);
2235: return;
2236: }
2237: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2238: return;
2239: if (c->mux_rcb(ssh, c) != 0) {
2240: debug("channel %d: mux_rcb failed", c->self);
2241: chan_mark_dead(ssh, c);
2242: return;
1.302 djm 2243: }
1.367 djm 2244: }
2245:
2246: static void
2247: channel_post_mux_client_write(struct ssh *ssh, Channel *c,
2248: fd_set *readset, fd_set *writeset)
2249: {
2250: ssize_t len;
2251: int r;
1.302 djm 2252:
1.367 djm 2253: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
2254: sshbuf_len(c->output) == 0)
2255: return;
2256:
2257: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 deraadt 2258: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2259: return;
2260: if (len <= 0) {
2261: chan_mark_dead(ssh, c);
2262: return;
1.302 djm 2263: }
1.367 djm 2264: if ((r = sshbuf_consume(c->output, len)) != 0)
2265: fatal("%s: channel %d: consume: %s", __func__,
2266: c->self, ssh_err(r));
2267: }
2268:
2269: static void
2270: channel_post_mux_client(struct ssh *ssh, Channel *c,
2271: fd_set *readset, fd_set *writeset)
2272: {
2273: channel_post_mux_client_read(ssh, c, readset, writeset);
2274: channel_post_mux_client_write(ssh, c, readset, writeset);
1.302 djm 2275: }
2276:
2277: static void
1.367 djm 2278: channel_post_mux_listener(struct ssh *ssh, Channel *c,
2279: fd_set *readset, fd_set *writeset)
1.302 djm 2280: {
2281: Channel *nc;
2282: struct sockaddr_storage addr;
2283: socklen_t addrlen;
2284: int newsock;
2285: uid_t euid;
2286: gid_t egid;
2287:
2288: if (!FD_ISSET(c->sock, readset))
2289: return;
2290:
2291: debug("multiplexing control connection");
2292:
2293: /*
2294: * Accept connection on control socket
2295: */
2296: memset(&addr, 0, sizeof(addr));
2297: addrlen = sizeof(addr);
2298: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2299: &addrlen)) == -1) {
2300: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 2301: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2302: c->notbefore = monotime() + 1;
1.302 djm 2303: return;
2304: }
2305:
1.393 deraadt 2306: if (getpeereid(newsock, &euid, &egid) == -1) {
1.302 djm 2307: error("%s getpeereid failed: %s", __func__,
2308: strerror(errno));
2309: close(newsock);
2310: return;
2311: }
2312: if ((euid != 0) && (getuid() != euid)) {
2313: error("multiplex uid mismatch: peer euid %u != uid %u",
2314: (u_int)euid, (u_int)getuid());
2315: close(newsock);
2316: return;
2317: }
1.367 djm 2318: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2319: newsock, newsock, -1, c->local_window_max,
2320: c->local_maxpacket, 0, "mux-control", 1);
2321: nc->mux_rcb = c->mux_rcb;
1.367 djm 2322: debug3("%s: new mux channel %d fd %d", __func__, nc->self, nc->sock);
1.302 djm 2323: /* establish state */
1.367 djm 2324: nc->mux_rcb(ssh, nc);
1.302 djm 2325: /* mux state transitions must not elicit protocol messages */
2326: nc->flags |= CHAN_LOCAL;
2327: }
2328:
1.127 itojun 2329: static void
1.367 djm 2330: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2331: {
1.367 djm 2332: chan_fn **pre, **post;
2333:
2334: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
2335: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
2336: fatal("%s: allocation failed", __func__);
2337:
2338: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2339: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2340: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2341: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2342: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2343: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2344: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2345: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2346: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2347: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2348: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2349: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2350: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2351:
2352: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2353: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2354: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2355: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2356: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2357: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2358: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2359: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2360: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2361: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2362: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2363: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2364:
1.367 djm 2365: sc->channel_pre = pre;
2366: sc->channel_post = post;
1.44 markus 2367: }
2368:
1.140 markus 2369: /* gc dead channels */
2370: static void
1.367 djm 2371: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2372: {
2373: if (c == NULL)
2374: return;
2375: if (c->detach_user != NULL) {
1.367 djm 2376: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2377: return;
1.385 djm 2378:
1.194 markus 2379: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2380: c->detach_user(ssh, c->self, NULL);
1.140 markus 2381: /* if we still have a callback */
2382: if (c->detach_user != NULL)
2383: return;
1.194 markus 2384: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2385: }
1.367 djm 2386: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2387: return;
1.194 markus 2388: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2389: channel_free(ssh, c);
1.140 markus 2390: }
2391:
1.367 djm 2392: enum channel_table { CHAN_PRE, CHAN_POST };
2393:
1.127 itojun 2394: static void
1.367 djm 2395: channel_handler(struct ssh *ssh, int table,
1.366 djm 2396: fd_set *readset, fd_set *writeset, time_t *unpause_secs)
1.41 markus 2397: {
1.367 djm 2398: struct ssh_channels *sc = ssh->chanctxt;
2399: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2400: u_int i, oalloc;
1.41 markus 2401: Channel *c;
1.317 djm 2402: time_t now;
1.25 markus 2403:
1.322 dtucker 2404: now = monotime();
1.317 djm 2405: if (unpause_secs != NULL)
2406: *unpause_secs = 0;
1.367 djm 2407: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2408: c = sc->channels[i];
1.113 markus 2409: if (c == NULL)
1.41 markus 2410: continue;
1.299 markus 2411: if (c->delayed) {
1.367 djm 2412: if (table == CHAN_PRE)
1.299 markus 2413: c->delayed = 0;
2414: else
2415: continue;
2416: }
1.317 djm 2417: if (ftab[c->type] != NULL) {
2418: /*
2419: * Run handlers that are not paused.
2420: */
2421: if (c->notbefore <= now)
1.367 djm 2422: (*ftab[c->type])(ssh, c, readset, writeset);
1.317 djm 2423: else if (unpause_secs != NULL) {
2424: /*
2425: * Collect the time that the earliest
2426: * channel comes off pause.
2427: */
2428: debug3("%s: chan %d: skip for %d more seconds",
2429: __func__, c->self,
2430: (int)(c->notbefore - now));
2431: if (*unpause_secs == 0 ||
2432: (c->notbefore - now) < *unpause_secs)
2433: *unpause_secs = c->notbefore - now;
2434: }
2435: }
1.367 djm 2436: channel_garbage_collect(ssh, c);
1.1 deraadt 2437: }
1.317 djm 2438: if (unpause_secs != NULL && *unpause_secs != 0)
2439: debug3("%s: first channel unpauses in %d seconds",
2440: __func__, (int)*unpause_secs);
1.1 deraadt 2441: }
2442:
1.121 markus 2443: /*
1.372 markus 2444: * Create sockets before allocating the select bitmasks.
2445: * This is necessary for things that need to happen after reading
2446: * the network-input but before channel_prepare_select().
2447: */
2448: static void
2449: channel_before_prepare_select(struct ssh *ssh)
2450: {
2451: struct ssh_channels *sc = ssh->chanctxt;
2452: Channel *c;
2453: u_int i, oalloc;
2454:
2455: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2456: c = sc->channels[i];
2457: if (c == NULL)
2458: continue;
2459: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
2460: channel_before_prepare_select_rdynamic(ssh, c);
2461: }
2462: }
2463:
2464: /*
1.121 markus 2465: * Allocate/update select bitmasks and add any bits relevant to channels in
2466: * select bitmasks.
2467: */
1.49 markus 2468: void
1.366 djm 2469: channel_prepare_select(struct ssh *ssh, fd_set **readsetp, fd_set **writesetp,
2470: int *maxfdp, u_int *nallocp, time_t *minwait_secs)
1.41 markus 2471: {
1.243 djm 2472: u_int n, sz, nfdset;
1.84 markus 2473:
1.372 markus 2474: channel_before_prepare_select(ssh); /* might update channel_max_fd */
2475:
1.367 djm 2476: n = MAXIMUM(*maxfdp, ssh->chanctxt->channel_max_fd);
1.84 markus 2477:
1.243 djm 2478: nfdset = howmany(n+1, NFDBITS);
2479: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2480: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2481: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2482: sz = nfdset * sizeof(fd_mask);
2483:
1.132 markus 2484: /* perhaps check sz < nalloc/2 and shrink? */
2485: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2486: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2487: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2488: *nallocp = sz;
1.84 markus 2489: }
1.132 markus 2490: *maxfdp = n;
1.84 markus 2491: memset(*readsetp, 0, sz);
2492: memset(*writesetp, 0, sz);
2493:
1.366 djm 2494: if (!ssh_packet_is_rekeying(ssh))
1.367 djm 2495: channel_handler(ssh, CHAN_PRE, *readsetp, *writesetp,
1.317 djm 2496: minwait_secs);
1.41 markus 2497: }
2498:
1.121 markus 2499: /*
2500: * After select, perform any appropriate operations for channels which have
2501: * events pending.
2502: */
1.49 markus 2503: void
1.366 djm 2504: channel_after_select(struct ssh *ssh, fd_set *readset, fd_set *writeset)
1.41 markus 2505: {
1.367 djm 2506: channel_handler(ssh, CHAN_POST, readset, writeset, NULL);
2507: }
2508:
2509: /*
2510: * Enqueue data for channels with open or draining c->input.
2511: */
2512: static void
2513: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2514: {
1.373 djm 2515: size_t len, plen;
2516: const u_char *pkt;
1.367 djm 2517: int r;
2518:
2519: if ((len = sshbuf_len(c->input)) == 0) {
2520: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2521: /*
2522: * input-buffer is empty and read-socket shutdown:
2523: * tell peer, that we will not send more data:
2524: * send IEOF.
2525: * hack for extended data: delay EOF if EFD still
2526: * in use.
2527: */
2528: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2529: debug2("channel %d: "
2530: "ibuf_empty delayed efd %d/(%zu)",
2531: c->self, c->efd, sshbuf_len(c->extended));
2532: else
2533: chan_ibuf_empty(ssh, c);
2534: }
2535: return;
2536: }
2537:
1.368 djm 2538: if (!c->have_remote_id)
2539: fatal(":%s: channel %d: no remote id", __func__, c->self);
2540:
1.367 djm 2541: if (c->datagram) {
2542: /* Check datagram will fit; drop if not */
1.373 djm 2543: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
2544: fatal("%s: channel %d: get datagram: %s", __func__,
1.367 djm 2545: c->self, ssh_err(r));
2546: /*
2547: * XXX this does tail-drop on the datagram queue which is
2548: * usually suboptimal compared to head-drop. Better to have
2549: * backpressure at read time? (i.e. read + discard)
2550: */
1.373 djm 2551: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2552: debug("channel %d: datagram too big", c->self);
2553: return;
2554: }
2555: /* Enqueue it */
2556: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2557: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2558: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.367 djm 2559: (r = sshpkt_send(ssh)) != 0) {
2560: fatal("%s: channel %i: datagram: %s", __func__,
2561: c->self, ssh_err(r));
2562: }
1.373 djm 2563: c->remote_window -= plen;
1.367 djm 2564: return;
2565: }
2566:
2567: /* Enqueue packet for buffered data. */
2568: if (len > c->remote_window)
2569: len = c->remote_window;
2570: if (len > c->remote_maxpacket)
2571: len = c->remote_maxpacket;
2572: if (len == 0)
2573: return;
2574: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2575: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2576: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
2577: (r = sshpkt_send(ssh)) != 0) {
2578: fatal("%s: channel %i: data: %s", __func__,
2579: c->self, ssh_err(r));
2580: }
2581: if ((r = sshbuf_consume(c->input, len)) != 0)
2582: fatal("%s: channel %i: consume: %s", __func__,
2583: c->self, ssh_err(r));
2584: c->remote_window -= len;
1.41 markus 2585: }
2586:
1.367 djm 2587: /*
2588: * Enqueue data for channels with open c->extended in read mode.
2589: */
2590: static void
2591: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2592: {
2593: size_t len;
2594: int r;
2595:
2596: if ((len = sshbuf_len(c->extended)) == 0)
2597: return;
2598:
2599: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2600: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2601: if (len > c->remote_window)
2602: len = c->remote_window;
2603: if (len > c->remote_maxpacket)
2604: len = c->remote_maxpacket;
2605: if (len == 0)
2606: return;
1.368 djm 2607: if (!c->have_remote_id)
2608: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.367 djm 2609: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2610: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2611: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2612: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
2613: (r = sshpkt_send(ssh)) != 0) {
2614: fatal("%s: channel %i: data: %s", __func__,
2615: c->self, ssh_err(r));
2616: }
2617: if ((r = sshbuf_consume(c->extended, len)) != 0)
2618: fatal("%s: channel %i: consume: %s", __func__,
2619: c->self, ssh_err(r));
2620: c->remote_window -= len;
2621: debug2("channel %d: sent ext data %zu", c->self, len);
2622: }
1.121 markus 2623:
1.84 markus 2624: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2625: void
1.367 djm 2626: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2627: {
1.367 djm 2628: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2629: Channel *c;
1.367 djm 2630: u_int i;
1.1 deraadt 2631:
1.367 djm 2632: for (i = 0; i < sc->channels_alloc; i++) {
2633: c = sc->channels[i];
1.113 markus 2634: if (c == NULL)
2635: continue;
1.37 markus 2636:
1.121 markus 2637: /*
2638: * We are only interested in channels that can have buffered
2639: * incoming data.
2640: */
1.358 djm 2641: if (c->type != SSH_CHANNEL_OPEN)
2642: continue;
2643: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2644: /* XXX is this true? */
1.367 djm 2645: debug3("channel %d: will not send data after close",
2646: c->self);
1.44 markus 2647: continue;
2648: }
1.25 markus 2649:
2650: /* Get the amount of buffered data for this channel. */
1.367 djm 2651: if (c->istate == CHAN_INPUT_OPEN ||
2652: c->istate == CHAN_INPUT_WAIT_DRAIN)
2653: channel_output_poll_input_open(ssh, c);
1.44 markus 2654: /* Send extended data, i.e. stderr */
1.358 djm 2655: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2656: c->extended_usage == CHAN_EXTENDED_READ)
2657: channel_output_poll_extended_read(ssh, c);
1.25 markus 2658: }
1.1 deraadt 2659: }
2660:
1.354 markus 2661: /* -- mux proxy support */
2662:
2663: /*
2664: * When multiplexing channel messages for mux clients we have to deal
2665: * with downstream messages from the mux client and upstream messages
2666: * from the ssh server:
2667: * 1) Handling downstream messages is straightforward and happens
2668: * in channel_proxy_downstream():
2669: * - We forward all messages (mostly) unmodified to the server.
2670: * - However, in order to route messages from upstream to the correct
2671: * downstream client, we have to replace the channel IDs used by the
2672: * mux clients with a unique channel ID because the mux clients might
2673: * use conflicting channel IDs.
2674: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2675: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2676: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2677: * with the newly allocated channel ID.
2678: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 2679: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 2680: * is then translated back to the original mux client ID.
2681: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2682: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2683: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2684: * downstream mux client are removed.
2685: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2686: * requires more work, because they are not addressed to a specific
2687: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2688: * out whether the request is addressed to the local client or a
2689: * specific downstream client based on the listen-address/port.
1.380 djm 2690: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 2691: * not supported as the matching session/channel cannot be identified
2692: * easily.
2693: */
2694:
2695: /*
2696: * receive packets from downstream mux clients:
2697: * channel callback fired on read from mux client, creates
2698: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2699: * on channel creation.
2700: */
2701: int
1.367 djm 2702: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2703: {
2704: Channel *c = NULL;
2705: struct sshbuf *original = NULL, *modified = NULL;
2706: const u_char *cp;
2707: char *ctype = NULL, *listen_host = NULL;
2708: u_char type;
2709: size_t have;
1.370 djm 2710: int ret = -1, r;
1.355 djm 2711: u_int id, remote_id, listen_port;
1.354 markus 2712:
1.367 djm 2713: /* sshbuf_dump(downstream->input, stderr); */
2714: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2715: != 0) {
2716: error("%s: malformed message: %s", __func__, ssh_err(r));
2717: return -1;
2718: }
2719: if (have < 2) {
2720: error("%s: short message", __func__);
2721: return -1;
2722: }
2723: type = cp[1];
2724: /* skip padlen + type */
2725: cp += 2;
2726: have -= 2;
2727: if (ssh_packet_log_type(type))
2728: debug3("%s: channel %u: down->up: type %u", __func__,
2729: downstream->self, type);
2730:
2731: switch (type) {
2732: case SSH2_MSG_CHANNEL_OPEN:
2733: if ((original = sshbuf_from(cp, have)) == NULL ||
2734: (modified = sshbuf_new()) == NULL) {
2735: error("%s: alloc", __func__);
2736: goto out;
2737: }
2738: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2739: (r = sshbuf_get_u32(original, &id)) != 0) {
2740: error("%s: parse error %s", __func__, ssh_err(r));
2741: goto out;
2742: }
1.367 djm 2743: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2744: -1, -1, -1, 0, 0, 0, ctype, 1);
2745: c->mux_ctx = downstream; /* point to mux client */
2746: c->mux_downstream_id = id; /* original downstream id */
2747: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2748: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2749: (r = sshbuf_putb(modified, original)) != 0) {
2750: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2751: channel_free(ssh, c);
1.354 markus 2752: goto out;
2753: }
2754: break;
2755: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2756: /*
2757: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2758: * need to parse 'remote_id' instead of 'ctype'.
2759: */
2760: if ((original = sshbuf_from(cp, have)) == NULL ||
2761: (modified = sshbuf_new()) == NULL) {
2762: error("%s: alloc", __func__);
2763: goto out;
2764: }
2765: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2766: (r = sshbuf_get_u32(original, &id)) != 0) {
2767: error("%s: parse error %s", __func__, ssh_err(r));
2768: goto out;
2769: }
1.367 djm 2770: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2771: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
2772: c->mux_ctx = downstream; /* point to mux client */
2773: c->mux_downstream_id = id;
2774: c->remote_id = remote_id;
1.368 djm 2775: c->have_remote_id = 1;
1.354 markus 2776: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2777: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2778: (r = sshbuf_putb(modified, original)) != 0) {
2779: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2780: channel_free(ssh, c);
1.354 markus 2781: goto out;
2782: }
2783: break;
2784: case SSH2_MSG_GLOBAL_REQUEST:
2785: if ((original = sshbuf_from(cp, have)) == NULL) {
2786: error("%s: alloc", __func__);
2787: goto out;
2788: }
2789: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
2790: error("%s: parse error %s", __func__, ssh_err(r));
2791: goto out;
2792: }
2793: if (strcmp(ctype, "tcpip-forward") != 0) {
2794: error("%s: unsupported request %s", __func__, ctype);
2795: goto out;
2796: }
2797: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2798: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2799: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
2800: error("%s: parse error %s", __func__, ssh_err(r));
2801: goto out;
2802: }
1.355 djm 2803: if (listen_port > 65535) {
2804: error("%s: tcpip-forward for %s: bad port %u",
2805: __func__, listen_host, listen_port);
2806: goto out;
2807: }
1.354 markus 2808: /* Record that connection to this host/port is permitted. */
1.381 djm 2809: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 2810: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 2811: listen_host = NULL;
2812: break;
2813: case SSH2_MSG_CHANNEL_CLOSE:
2814: if (have < 4)
2815: break;
2816: remote_id = PEEK_U32(cp);
1.367 djm 2817: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 2818: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 2819: channel_free(ssh, c);
1.354 markus 2820: else
2821: c->flags |= CHAN_CLOSE_SENT;
2822: }
2823: break;
2824: }
2825: if (modified) {
2826: if ((r = sshpkt_start(ssh, type)) != 0 ||
2827: (r = sshpkt_putb(ssh, modified)) != 0 ||
2828: (r = sshpkt_send(ssh)) != 0) {
2829: error("%s: send %s", __func__, ssh_err(r));
2830: goto out;
2831: }
2832: } else {
2833: if ((r = sshpkt_start(ssh, type)) != 0 ||
2834: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2835: (r = sshpkt_send(ssh)) != 0) {
2836: error("%s: send %s", __func__, ssh_err(r));
2837: goto out;
2838: }
2839: }
2840: ret = 0;
2841: out:
2842: free(ctype);
2843: free(listen_host);
2844: sshbuf_free(original);
2845: sshbuf_free(modified);
2846: return ret;
2847: }
2848:
2849: /*
2850: * receive packets from upstream server and de-multiplex packets
2851: * to correct downstream:
2852: * implemented as a helper for channel input handlers,
2853: * replaces local (proxy) channel ID with downstream channel ID.
2854: */
2855: int
1.363 markus 2856: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 2857: {
2858: struct sshbuf *b = NULL;
2859: Channel *downstream;
2860: const u_char *cp = NULL;
2861: size_t len;
2862: int r;
2863:
2864: /*
2865: * When receiving packets from the peer we need to check whether we
2866: * need to forward the packets to the mux client. In this case we
1.380 djm 2867: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 2868: * so we can cleanup the channel.
2869: */
2870: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2871: return 0;
2872: if ((downstream = c->mux_ctx) == NULL)
2873: return 0;
2874: switch (type) {
2875: case SSH2_MSG_CHANNEL_CLOSE:
2876: case SSH2_MSG_CHANNEL_DATA:
2877: case SSH2_MSG_CHANNEL_EOF:
2878: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2879: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2880: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2881: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2882: case SSH2_MSG_CHANNEL_SUCCESS:
2883: case SSH2_MSG_CHANNEL_FAILURE:
2884: case SSH2_MSG_CHANNEL_REQUEST:
2885: break;
2886: default:
2887: debug2("%s: channel %u: unsupported type %u", __func__,
2888: c->self, type);
2889: return 0;
2890: }
2891: if ((b = sshbuf_new()) == NULL) {
2892: error("%s: alloc reply", __func__);
2893: goto out;
2894: }
2895: /* get remaining payload (after id) */
2896: cp = sshpkt_ptr(ssh, &len);
2897: if (cp == NULL) {
2898: error("%s: no packet", __func__);
2899: goto out;
2900: }
2901: /* translate id and send to muxclient */
2902: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2903: (r = sshbuf_put_u8(b, type)) != 0 ||
2904: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2905: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 2906: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.354 markus 2907: error("%s: compose for muxclient %s", __func__, ssh_err(r));
2908: goto out;
2909: }
2910: /* sshbuf_dump(b, stderr); */
2911: if (ssh_packet_log_type(type))
2912: debug3("%s: channel %u: up->down: type %u", __func__, c->self,
2913: type);
2914: out:
2915: /* update state */
2916: switch (type) {
2917: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2918: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 2919: if (cp && len > 4) {
1.354 markus 2920: c->remote_id = PEEK_U32(cp);
1.368 djm 2921: c->have_remote_id = 1;
2922: }
1.354 markus 2923: break;
2924: case SSH2_MSG_CHANNEL_CLOSE:
2925: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 2926: channel_free(ssh, c);
1.354 markus 2927: else
2928: c->flags |= CHAN_CLOSE_RCVD;
2929: break;
2930: }
2931: sshbuf_free(b);
2932: return 1;
2933: }
1.121 markus 2934:
2935: /* -- protocol input */
1.249 djm 2936:
1.367 djm 2937: /* Parse a channel ID from the current packet */
2938: static int
2939: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
2940: {
2941: u_int32_t id;
2942: int r;
2943:
2944: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
2945: error("%s: parse id: %s", where, ssh_err(r));
2946: ssh_packet_disconnect(ssh, "Invalid %s message", what);
2947: }
2948: if (id > INT_MAX) {
2949: error("%s: bad channel id %u: %s", where, id, ssh_err(r));
2950: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
2951: }
2952: return (int)id;
2953: }
2954:
2955: /* Lookup a channel from an ID in the current packet */
2956: static Channel *
2957: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
2958: {
2959: int id = channel_parse_id(ssh, where, what);
2960: Channel *c;
2961:
2962: if ((c = channel_lookup(ssh, id)) == NULL) {
2963: ssh_packet_disconnect(ssh,
2964: "%s packet referred to nonexistent channel %d", what, id);
2965: }
2966: return c;
2967: }
2968:
1.339 markus 2969: int
1.363 markus 2970: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2971: {
1.332 djm 2972: const u_char *data;
1.367 djm 2973: size_t data_len, win_len;
2974: Channel *c = channel_from_packet_id(ssh, __func__, "data");
2975: int r;
1.25 markus 2976:
1.363 markus 2977: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2978: return 0;
1.25 markus 2979:
2980: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2981: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 2982: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
2983: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 2984: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2985: return 0;
1.37 markus 2986:
1.25 markus 2987: /* Get the data. */
1.389 djm 2988: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
2989: (r = sshpkt_get_end(ssh)) != 0)
1.367 djm 2990: fatal("%s: channel %d: get data: %s", __func__,
2991: c->self, ssh_err(r));
2992:
1.309 djm 2993: win_len = data_len;
2994: if (c->datagram)
2995: win_len += 4; /* string length header */
1.200 markus 2996:
2997: /*
1.367 djm 2998: * The sending side reduces its window as it sends data, so we
2999: * must 'fake' consumption of the data in order to ensure that window
3000: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 3001: */
1.358 djm 3002: if (c->ostate != CHAN_OUTPUT_OPEN) {
3003: c->local_window -= win_len;
3004: c->local_consumed += win_len;
1.339 markus 3005: return 0;
1.200 markus 3006: }
1.41 markus 3007:
1.358 djm 3008: if (win_len > c->local_maxpacket) {
1.367 djm 3009: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 3010: c->self, win_len, c->local_maxpacket);
1.367 djm 3011: return 0;
1.358 djm 3012: }
3013: if (win_len > c->local_window) {
1.367 djm 3014: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 3015: c->self, win_len, c->local_window);
3016: return 0;
1.44 markus 3017: }
1.358 djm 3018: c->local_window -= win_len;
3019:
1.367 djm 3020: if (c->datagram) {
3021: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
3022: fatal("%s: channel %d: append datagram: %s",
3023: __func__, c->self, ssh_err(r));
3024: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
3025: fatal("%s: channel %d: append data: %s",
3026: __func__, c->self, ssh_err(r));
3027:
1.339 markus 3028: return 0;
1.1 deraadt 3029: }
1.121 markus 3030:
1.339 markus 3031: int
1.363 markus 3032: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 3033: {
1.367 djm 3034: const u_char *data;
3035: size_t data_len;
3036: u_int32_t tcode;
3037: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
3038: int r;
1.44 markus 3039:
1.363 markus 3040: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3041: return 0;
1.44 markus 3042: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 3043: logit("channel %d: ext data for non open", c->self);
1.339 markus 3044: return 0;
1.172 markus 3045: }
3046: if (c->flags & CHAN_EOF_RCVD) {
3047: if (datafellows & SSH_BUG_EXTEOF)
1.367 djm 3048: debug("channel %d: accepting ext data after eof",
3049: c->self);
1.172 markus 3050: else
1.367 djm 3051: ssh_packet_disconnect(ssh, "Received extended_data "
3052: "after EOF on channel %d.", c->self);
3053: }
3054:
3055: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
3056: error("%s: parse tcode: %s", __func__, ssh_err(r));
3057: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3058: }
3059: if (c->efd == -1 ||
3060: c->extended_usage != CHAN_EXTENDED_WRITE ||
3061: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3062: logit("channel %d: bad ext data", c->self);
1.339 markus 3063: return 0;
1.44 markus 3064: }
1.389 djm 3065: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3066: (r = sshpkt_get_end(ssh)) != 0) {
1.367 djm 3067: error("%s: parse data: %s", __func__, ssh_err(r));
3068: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3069: }
3070:
1.44 markus 3071: if (data_len > c->local_window) {
1.367 djm 3072: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3073: c->self, data_len, c->local_window);
1.339 markus 3074: return 0;
1.44 markus 3075: }
1.367 djm 3076: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3077: /* XXX sshpkt_getb? */
3078: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
3079: error("%s: append: %s", __func__, ssh_err(r));
1.44 markus 3080: c->local_window -= data_len;
1.339 markus 3081: return 0;
1.44 markus 3082: }
3083:
1.339 markus 3084: int
1.363 markus 3085: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3086: {
1.367 djm 3087: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3088: int r;
1.367 djm 3089:
1.389 djm 3090: if ((r = sshpkt_get_end(ssh)) != 0) {
3091: error("%s: parse data: %s", __func__, ssh_err(r));
3092: ssh_packet_disconnect(ssh, "Invalid ieof message");
3093: }
1.41 markus 3094:
1.363 markus 3095: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3096: return 0;
1.367 djm 3097: chan_rcvd_ieof(ssh, c);
1.133 markus 3098:
3099: /* XXX force input close */
1.156 markus 3100: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3101: debug("channel %d: FORCE input drain", c->self);
3102: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3103: if (sshbuf_len(c->input) == 0)
3104: chan_ibuf_empty(ssh, c);
1.133 markus 3105: }
1.339 markus 3106: return 0;
1.41 markus 3107: }
1.1 deraadt 3108:
1.339 markus 3109: int
1.363 markus 3110: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3111: {
1.367 djm 3112: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3113: int r;
1.151 markus 3114:
1.363 markus 3115: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3116: return 0;
1.389 djm 3117: if ((r = sshpkt_get_end(ssh)) != 0) {
3118: error("%s: parse data: %s", __func__, ssh_err(r));
3119: ssh_packet_disconnect(ssh, "Invalid oclose message");
3120: }
1.367 djm 3121: chan_rcvd_oclose(ssh, c);
1.339 markus 3122: return 0;
1.1 deraadt 3123: }
3124:
1.339 markus 3125: int
1.363 markus 3126: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3127: {
1.367 djm 3128: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3129: u_int32_t remote_window, remote_maxpacket;
3130: int r;
1.25 markus 3131:
1.363 markus 3132: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3133: return 0;
3134: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3135: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3136: "non-opening channel %d.", c->self);
3137: /*
3138: * Record the remote channel number and mark that the channel
3139: * is now open.
3140: */
1.368 djm 3141: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3142: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3143: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3144: (r = sshpkt_get_end(ssh)) != 0) {
1.367 djm 3145: error("%s: window/maxpacket: %s", __func__, ssh_err(r));
1.389 djm 3146: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3147: }
3148:
1.368 djm 3149: c->have_remote_id = 1;
1.367 djm 3150: c->remote_window = remote_window;
3151: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3152: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3153: if (c->open_confirm) {
1.367 djm 3154: debug2("%s: channel %d: callback start", __func__, c->self);
3155: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
3156: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3157: }
1.358 djm 3158: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3159: c->remote_window, c->remote_maxpacket);
1.339 markus 3160: return 0;
1.1 deraadt 3161: }
3162:
1.127 itojun 3163: static char *
1.114 markus 3164: reason2txt(int reason)
3165: {
1.143 deraadt 3166: switch (reason) {
1.114 markus 3167: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3168: return "administratively prohibited";
3169: case SSH2_OPEN_CONNECT_FAILED:
3170: return "connect failed";
3171: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3172: return "unknown channel type";
3173: case SSH2_OPEN_RESOURCE_SHORTAGE:
3174: return "resource shortage";
3175: }
1.117 stevesk 3176: return "unknown reason";
1.114 markus 3177: }
3178:
1.339 markus 3179: int
1.363 markus 3180: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3181: {
1.367 djm 3182: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3183: u_int32_t reason;
3184: char *msg = NULL;
3185: int r;
1.25 markus 3186:
1.363 markus 3187: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3188: return 0;
3189: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3190: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3191: "non-opening channel %d.", c->self);
3192: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
3193: error("%s: reason: %s", __func__, ssh_err(r));
1.389 djm 3194: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3195: }
1.378 djm 3196: /* skip language */
3197: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3198: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3199: (r = sshpkt_get_end(ssh)) != 0) {
1.378 djm 3200: error("%s: message/lang: %s", __func__, ssh_err(r));
1.389 djm 3201: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3202: }
1.367 djm 3203: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3204: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3205: free(msg);
3206: if (c->open_confirm) {
1.367 djm 3207: debug2("%s: channel %d: callback start", __func__, c->self);
3208: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
3209: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3210: }
1.291 djm 3211: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3212: chan_mark_dead(ssh, c);
1.339 markus 3213: return 0;
1.44 markus 3214: }
3215:
1.339 markus 3216: int
1.363 markus 3217: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3218: {
1.367 djm 3219: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3220: Channel *c;
1.367 djm 3221: u_int32_t adjust;
3222: u_int new_rwin;
3223: int r;
1.1 deraadt 3224:
1.367 djm 3225: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3226: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3227: return 0;
1.372 markus 3228: }
1.367 djm 3229:
1.363 markus 3230: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3231: return 0;
1.389 djm 3232: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3233: (r = sshpkt_get_end(ssh)) != 0) {
1.367 djm 3234: error("%s: adjust: %s", __func__, ssh_err(r));
1.389 djm 3235: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3236: }
3237: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3238: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3239: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3240: c->self, adjust, c->remote_window);
3241: }
3242: c->remote_window = new_rwin;
1.339 markus 3243: return 0;
1.121 markus 3244: }
1.1 deraadt 3245:
1.339 markus 3246: int
1.363 markus 3247: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3248: {
1.367 djm 3249: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3250: Channel *c;
3251: struct channel_confirm *cc;
3252:
3253: /* Reset keepalive timeout */
1.389 djm 3254: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3255:
1.367 djm 3256: debug2("%s: type %d id %d", __func__, type, id);
1.275 djm 3257:
1.367 djm 3258: if ((c = channel_lookup(ssh, id)) == NULL) {
3259: logit("%s: %d: unknown", __func__, id);
1.339 markus 3260: return 0;
1.367 djm 3261: }
1.363 markus 3262: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3263: return 0;
1.394 dtucker 3264: if (sshpkt_get_end(ssh) != 0)
1.389 djm 3265: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3266: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3267: return 0;
1.367 djm 3268: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3269: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 3270: freezero(cc, sizeof(*cc));
1.339 markus 3271: return 0;
1.275 djm 3272: }
1.121 markus 3273:
3274: /* -- tcp forwarding */
1.135 markus 3275:
3276: void
1.367 djm 3277: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3278: {
1.367 djm 3279: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3280: }
1.121 markus 3281:
1.312 djm 3282:
3283: /*
3284: * Determine whether or not a port forward listens to loopback, the
3285: * specified address or wildcard. On the client, a specified bind
3286: * address will always override gateway_ports. On the server, a
3287: * gateway_ports of 1 (``yes'') will override the client's specification
3288: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3289: * will bind to whatever address the client asked for.
3290: *
3291: * Special-case listen_addrs are:
3292: *
3293: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3294: * "" (empty string), "*" -> wildcard v4/v6
3295: * "localhost" -> loopback v4/v6
1.334 djm 3296: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3297: */
3298: static const char *
1.389 djm 3299: channel_fwd_bind_addr(struct ssh *ssh, const char *listen_addr, int *wildcardp,
1.336 millert 3300: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3301: {
3302: const char *addr = NULL;
3303: int wildcard = 0;
3304:
3305: if (listen_addr == NULL) {
3306: /* No address specified: default to gateway_ports setting */
1.336 millert 3307: if (fwd_opts->gateway_ports)
1.312 djm 3308: wildcard = 1;
1.336 millert 3309: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 3310: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
3311: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3312: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3313: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3314: wildcard = 1;
1.326 djm 3315: /*
3316: * Notify client if they requested a specific listen
3317: * address and it was overridden.
3318: */
3319: if (*listen_addr != '\0' &&
3320: strcmp(listen_addr, "0.0.0.0") != 0 &&
3321: strcmp(listen_addr, "*") != 0) {
1.389 djm 3322: ssh_packet_send_debug(ssh,
3323: "Forwarding listen address "
1.326 djm 3324: "\"%s\" overridden by server "
3325: "GatewayPorts", listen_addr);
3326: }
1.334 djm 3327: } else if (strcmp(listen_addr, "localhost") != 0 ||
3328: strcmp(listen_addr, "127.0.0.1") == 0 ||
3329: strcmp(listen_addr, "::1") == 0) {
1.395 djm 3330: /*
3331: * Accept explicit localhost address when
3332: * GatewayPorts=yes. The "localhost" hostname is
3333: * deliberately skipped here so it will listen on all
3334: * available local address families.
3335: */
1.334 djm 3336: addr = listen_addr;
1.326 djm 3337: }
1.334 djm 3338: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3339: strcmp(listen_addr, "::1") == 0) {
3340: /*
3341: * If a specific IPv4/IPv6 localhost address has been
3342: * requested then accept it even if gateway_ports is in
3343: * effect. This allows the client to prefer IPv4 or IPv6.
3344: */
3345: addr = listen_addr;
1.312 djm 3346: }
3347: if (wildcardp != NULL)
3348: *wildcardp = wildcard;
3349: return addr;
3350: }
3351:
1.160 markus 3352: static int
1.367 djm 3353: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3354: struct Forward *fwd, int *allocated_listen_port,
3355: struct ForwardOptions *fwd_opts)
1.25 markus 3356: {
1.113 markus 3357: Channel *c;
1.226 djm 3358: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3359: struct addrinfo hints, *ai, *aitop;
1.212 djm 3360: const char *host, *addr;
1.35 markus 3361: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3362: in_port_t *lport_p;
1.25 markus 3363:
1.212 djm 3364: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3365:
1.344 millert 3366: if (is_client && fwd->connect_path != NULL) {
3367: host = fwd->connect_path;
3368: } else {
3369: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3370: fwd->listen_host : fwd->connect_host;
3371: if (host == NULL) {
3372: error("No forward host name.");
3373: return 0;
3374: }
3375: if (strlen(host) >= NI_MAXHOST) {
3376: error("Forward host name too long.");
3377: return 0;
3378: }
1.87 markus 3379: }
1.25 markus 3380:
1.312 djm 3381: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3382: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3383: is_client, fwd_opts);
3384: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 3385: type, wildcard, (addr == NULL) ? "NULL" : addr);
3386:
3387: /*
1.35 markus 3388: * getaddrinfo returns a loopback address if the hostname is
3389: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3390: */
1.35 markus 3391: memset(&hints, 0, sizeof(hints));
1.367 djm 3392: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3393: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3394: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3395: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3396: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3397: if (addr == NULL) {
3398: /* This really shouldn't happen */
1.389 djm 3399: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3400: ssh_gai_strerror(r));
1.212 djm 3401: } else {
1.336 millert 3402: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 3403: ssh_gai_strerror(r));
1.212 djm 3404: }
1.218 markus 3405: return 0;
1.212 djm 3406: }
1.295 djm 3407: if (allocated_listen_port != NULL)
3408: *allocated_listen_port = 0;
1.35 markus 3409: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3410: switch (ai->ai_family) {
3411: case AF_INET:
3412: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3413: sin_port;
3414: break;
3415: case AF_INET6:
3416: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3417: sin6_port;
3418: break;
3419: default:
1.35 markus 3420: continue;
1.295 djm 3421: }
3422: /*
3423: * If allocating a port for -R forwards, then use the
3424: * same port for all address families.
3425: */
1.367 djm 3426: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3427: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3428: *allocated_listen_port > 0)
1.295 djm 3429: *lport_p = htons(*allocated_listen_port);
3430:
1.35 markus 3431: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3432: strport, sizeof(strport),
3433: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 3434: error("%s: getnameinfo failed", __func__);
1.35 markus 3435: continue;
3436: }
3437: /* Create a port to listen for the host. */
1.300 dtucker 3438: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 3439: if (sock == -1) {
1.35 markus 3440: /* this is no error since kernel may not support ipv6 */
1.377 djm 3441: verbose("socket [%s]:%s: %.100s", ntop, strport,
3442: strerror(errno));
1.35 markus 3443: continue;
3444: }
1.226 djm 3445:
1.376 djm 3446: set_reuseaddr(sock);
1.182 stevesk 3447:
1.295 djm 3448: debug("Local forwarding listening on %s port %s.",
3449: ntop, strport);
1.35 markus 3450:
3451: /* Bind the socket to the address. */
1.393 deraadt 3452: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3453: /*
3454: * address can be in if use ipv6 address is
3455: * already bound
3456: */
1.377 djm 3457: verbose("bind [%s]:%s: %.100s",
3458: ntop, strport, strerror(errno));
1.35 markus 3459: close(sock);
3460: continue;
3461: }
3462: /* Start listening for connections on the socket. */
1.393 deraadt 3463: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3464: error("listen [%s]:%s: %.100s", ntop, strport,
3465: strerror(errno));
1.35 markus 3466: close(sock);
3467: continue;
3468: }
1.295 djm 3469:
3470: /*
1.336 millert 3471: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3472: * record what we got.
3473: */
1.367 djm 3474: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3475: fwd->listen_port == 0 &&
1.295 djm 3476: allocated_listen_port != NULL &&
3477: *allocated_listen_port == 0) {
1.350 djm 3478: *allocated_listen_port = get_local_port(sock);
1.295 djm 3479: debug("Allocated listen port %d",
3480: *allocated_listen_port);
3481: }
3482:
1.35 markus 3483: /* Allocate a channel number for the socket. */
1.367 djm 3484: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3485: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3486: 0, "port listener", 1);
1.293 djm 3487: c->path = xstrdup(host);
1.336 millert 3488: c->host_port = fwd->connect_port;
1.312 djm 3489: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3490: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 3491: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
3492: c->listening_port = *allocated_listen_port;
3493: else
1.336 millert 3494: c->listening_port = fwd->listen_port;
1.35 markus 3495: success = 1;
3496: }
3497: if (success == 0)
1.336 millert 3498: error("%s: cannot listen to port: %d", __func__,
3499: fwd->listen_port);
1.35 markus 3500: freeaddrinfo(aitop);
1.87 markus 3501: return success;
1.25 markus 3502: }
1.1 deraadt 3503:
1.336 millert 3504: static int
1.367 djm 3505: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3506: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3507: {
3508: struct sockaddr_un sunaddr;
3509: const char *path;
3510: Channel *c;
3511: int port, sock;
3512: mode_t omask;
3513:
3514: switch (type) {
3515: case SSH_CHANNEL_UNIX_LISTENER:
3516: if (fwd->connect_path != NULL) {
3517: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3518: error("Local connecting path too long: %s",
3519: fwd->connect_path);
3520: return 0;
3521: }
3522: path = fwd->connect_path;
3523: port = PORT_STREAMLOCAL;
3524: } else {
3525: if (fwd->connect_host == NULL) {
3526: error("No forward host name.");
3527: return 0;
3528: }
3529: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3530: error("Forward host name too long.");
3531: return 0;
3532: }
3533: path = fwd->connect_host;
3534: port = fwd->connect_port;
3535: }
3536: break;
3537: case SSH_CHANNEL_RUNIX_LISTENER:
3538: path = fwd->listen_path;
3539: port = PORT_STREAMLOCAL;
3540: break;
3541: default:
3542: error("%s: unexpected channel type %d", __func__, type);
3543: return 0;
3544: }
3545:
3546: if (fwd->listen_path == NULL) {
3547: error("No forward path name.");
3548: return 0;
3549: }
3550: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3551: error("Local listening path too long: %s", fwd->listen_path);
3552: return 0;
3553: }
3554:
3555: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
3556:
3557: /* Start a Unix domain listener. */
3558: omask = umask(fwd_opts->streamlocal_bind_mask);
3559: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3560: fwd_opts->streamlocal_bind_unlink);
3561: umask(omask);
3562: if (sock < 0)
3563: return 0;
3564:
3565: debug("Local forwarding listening on path %s.", fwd->listen_path);
3566:
3567: /* Allocate a channel number for the socket. */
1.367 djm 3568: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3569: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3570: 0, "unix listener", 1);
3571: c->path = xstrdup(path);
3572: c->host_port = port;
3573: c->listening_port = PORT_STREAMLOCAL;
3574: c->listening_addr = xstrdup(fwd->listen_path);
3575: return 1;
3576: }
3577:
3578: static int
1.367 djm 3579: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3580: const char *host, u_short port)
1.202 djm 3581: {
1.209 avsm 3582: u_int i;
3583: int found = 0;
1.202 djm 3584:
1.367 djm 3585: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3586: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3587: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3588: continue;
3589: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3590: debug2("%s: close channel %d", __func__, i);
1.367 djm 3591: channel_free(ssh, c);
1.312 djm 3592: found = 1;
3593: }
3594: }
3595:
1.367 djm 3596: return found;
1.312 djm 3597: }
3598:
1.336 millert 3599: static int
1.367 djm 3600: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3601: {
3602: u_int i;
3603: int found = 0;
3604:
1.367 djm 3605: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3606: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3607: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3608: continue;
3609: if (c->path == NULL)
3610: continue;
3611: if (strcmp(c->path, path) == 0) {
3612: debug2("%s: close channel %d", __func__, i);
1.367 djm 3613: channel_free(ssh, c);
1.336 millert 3614: found = 1;
3615: }
3616: }
3617:
1.367 djm 3618: return found;
1.336 millert 3619: }
3620:
1.312 djm 3621: int
1.367 djm 3622: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3623: {
1.367 djm 3624: if (fwd->listen_path != NULL) {
3625: return channel_cancel_rport_listener_streamlocal(ssh,
3626: fwd->listen_path);
3627: } else {
3628: return channel_cancel_rport_listener_tcpip(ssh,
3629: fwd->listen_host, fwd->listen_port);
3630: }
1.336 millert 3631: }
3632:
3633: static int
1.367 djm 3634: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3635: const char *lhost, u_short lport, int cport,
3636: struct ForwardOptions *fwd_opts)
1.312 djm 3637: {
3638: u_int i;
3639: int found = 0;
1.389 djm 3640: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 3641:
1.367 djm 3642: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3643: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3644: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3645: continue;
1.313 markus 3646: if (c->listening_port != lport)
1.312 djm 3647: continue;
1.313 markus 3648: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3649: /* skip dynamic forwardings */
3650: if (c->host_port == 0)
3651: continue;
3652: } else {
3653: if (c->host_port != cport)
3654: continue;
3655: }
1.312 djm 3656: if ((c->listening_addr == NULL && addr != NULL) ||
3657: (c->listening_addr != NULL && addr == NULL))
3658: continue;
3659: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3660: debug2("%s: close channel %d", __func__, i);
1.367 djm 3661: channel_free(ssh, c);
1.202 djm 3662: found = 1;
3663: }
3664: }
3665:
1.367 djm 3666: return found;
1.202 djm 3667: }
3668:
1.336 millert 3669: static int
1.367 djm 3670: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3671: {
3672: u_int i;
3673: int found = 0;
3674:
3675: if (path == NULL) {
3676: error("%s: no path specified.", __func__);
3677: return 0;
3678: }
3679:
1.367 djm 3680: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3681: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3682: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3683: continue;
3684: if (c->listening_addr == NULL)
3685: continue;
3686: if (strcmp(c->listening_addr, path) == 0) {
3687: debug2("%s: close channel %d", __func__, i);
1.367 djm 3688: channel_free(ssh, c);
1.336 millert 3689: found = 1;
3690: }
3691: }
3692:
1.367 djm 3693: return found;
1.336 millert 3694: }
3695:
3696: int
1.367 djm 3697: channel_cancel_lport_listener(struct ssh *ssh,
3698: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3699: {
1.367 djm 3700: if (fwd->listen_path != NULL) {
3701: return channel_cancel_lport_listener_streamlocal(ssh,
3702: fwd->listen_path);
3703: } else {
3704: return channel_cancel_lport_listener_tcpip(ssh,
3705: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3706: }
1.336 millert 3707: }
3708:
1.362 markus 3709: /* protocol local port fwd, used by ssh */
1.160 markus 3710: int
1.367 djm 3711: channel_setup_local_fwd_listener(struct ssh *ssh,
3712: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3713: {
1.336 millert 3714: if (fwd->listen_path != NULL) {
1.367 djm 3715: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3716: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3717: } else {
1.367 djm 3718: return channel_setup_fwd_listener_tcpip(ssh,
3719: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3720: }
1.160 markus 3721: }
3722:
1.381 djm 3723: /* Matches a remote forwarding permission against a requested forwarding */
3724: static int
3725: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
3726: {
3727: int ret;
3728: char *lhost;
3729:
3730: /* XXX add ACLs for streamlocal */
3731: if (fwd->listen_path != NULL)
3732: return 1;
3733:
3734: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
3735: return 0;
3736:
3737: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
3738: allowed_open->listen_port != fwd->listen_port)
3739: return 0;
3740:
3741: /* Match hostnames case-insensitively */
3742: lhost = xstrdup(fwd->listen_host);
3743: lowercase(lhost);
3744: ret = match_pattern(lhost, allowed_open->listen_host);
3745: free(lhost);
3746:
3747: return ret;
3748: }
3749:
3750: /* Checks whether a requested remote forwarding is permitted */
3751: static int
3752: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
3753: {
3754: struct ssh_channels *sc = ssh->chanctxt;
3755: struct permission_set *pset = &sc->remote_perms;
3756: u_int i, permit, permit_adm = 1;
3757: struct permission *perm;
3758:
3759: /* XXX apply GatewayPorts override before checking? */
3760:
3761: permit = pset->all_permitted;
3762: if (!permit) {
3763: for (i = 0; i < pset->num_permitted_user; i++) {
3764: perm = &pset->permitted_user[i];
3765: if (remote_open_match(perm, fwd)) {
3766: permit = 1;
3767: break;
3768: }
3769: }
3770: }
3771:
3772: if (pset->num_permitted_admin > 0) {
3773: permit_adm = 0;
3774: for (i = 0; i < pset->num_permitted_admin; i++) {
3775: perm = &pset->permitted_admin[i];
3776: if (remote_open_match(perm, fwd)) {
3777: permit_adm = 1;
3778: break;
3779: }
3780: }
3781: }
3782:
3783: return permit && permit_adm;
3784: }
3785:
1.160 markus 3786: /* protocol v2 remote port fwd, used by sshd */
3787: int
1.367 djm 3788: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3789: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3790: {
1.381 djm 3791: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 3792: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 3793: if (fwd->listen_path != NULL)
3794: /* XXX always allowed, see remote_open_match() */
3795: logit("Received request from %.100s port %d to "
3796: "remote forward to path \"%.100s\", "
3797: "but the request was denied.",
3798: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3799: fwd->listen_path);
3800: else if(fwd->listen_host != NULL)
3801: logit("Received request from %.100s port %d to "
3802: "remote forward to host %.100s port %d, "
3803: "but the request was denied.",
3804: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3805: fwd->listen_host, fwd->listen_port );
3806: else
3807: logit("Received request from %.100s port %d to remote "
3808: "forward, but the request was denied.",
3809: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 3810: return 0;
3811: }
1.336 millert 3812: if (fwd->listen_path != NULL) {
1.367 djm 3813: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3814: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3815: } else {
1.367 djm 3816: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 3817: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3818: fwd_opts);
3819: }
1.160 markus 3820: }
3821:
1.27 markus 3822: /*
1.312 djm 3823: * Translate the requested rfwd listen host to something usable for
3824: * this server.
3825: */
3826: static const char *
3827: channel_rfwd_bind_host(const char *listen_host)
3828: {
3829: if (listen_host == NULL) {
1.378 djm 3830: return "localhost";
1.312 djm 3831: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 3832: return "";
1.312 djm 3833: } else
3834: return listen_host;
3835: }
3836:
3837: /*
1.27 markus 3838: * Initiate forwarding of connections to port "port" on remote host through
3839: * the secure channel to host:port from local side.
1.315 markus 3840: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 3841: * channel_update_permission().
1.27 markus 3842: */
1.253 markus 3843: int
1.367 djm 3844: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 3845: {
1.367 djm 3846: int r, success = 0, idx = -1;
3847: char *host_to_connect, *listen_host, *listen_path;
3848: int port_to_connect, listen_port;
1.73 markus 3849:
1.25 markus 3850: /* Send the forward request to the remote side. */
1.358 djm 3851: if (fwd->listen_path != NULL) {
1.367 djm 3852: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3853: (r = sshpkt_put_cstring(ssh,
3854: "streamlocal-forward@openssh.com")) != 0 ||
3855: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3856: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3857: (r = sshpkt_send(ssh)) != 0 ||
3858: (r = ssh_packet_write_wait(ssh)) != 0)
3859: fatal("%s: request streamlocal: %s",
3860: __func__, ssh_err(r));
1.336 millert 3861: } else {
1.367 djm 3862: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3863: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
3864: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3865: (r = sshpkt_put_cstring(ssh,
3866: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
3867: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
3868: (r = sshpkt_send(ssh)) != 0 ||
3869: (r = ssh_packet_write_wait(ssh)) != 0)
3870: fatal("%s: request tcpip-forward: %s",
3871: __func__, ssh_err(r));
1.73 markus 3872: }
1.358 djm 3873: /* Assume that server accepts the request */
3874: success = 1;
1.73 markus 3875: if (success) {
1.305 djm 3876: /* Record that connection to this host/port is permitted. */
1.367 djm 3877: host_to_connect = listen_host = listen_path = NULL;
3878: port_to_connect = listen_port = 0;
1.336 millert 3879: if (fwd->connect_path != NULL) {
1.367 djm 3880: host_to_connect = xstrdup(fwd->connect_path);
3881: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 3882: } else {
1.367 djm 3883: host_to_connect = xstrdup(fwd->connect_host);
3884: port_to_connect = fwd->connect_port;
1.336 millert 3885: }
3886: if (fwd->listen_path != NULL) {
1.367 djm 3887: listen_path = xstrdup(fwd->listen_path);
3888: listen_port = PORT_STREAMLOCAL;
1.336 millert 3889: } else {
1.367 djm 3890: if (fwd->listen_host != NULL)
3891: listen_host = xstrdup(fwd->listen_host);
3892: listen_port = fwd->listen_port;
3893: }
1.381 djm 3894: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 3895: host_to_connect, port_to_connect,
3896: listen_host, listen_path, listen_port, NULL);
1.44 markus 3897: }
1.367 djm 3898: return idx;
1.1 deraadt 3899: }
3900:
1.333 markus 3901: static int
1.381 djm 3902: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 3903: int requestedport)
1.333 markus 3904: {
3905: if (allowed_open->host_to_connect == NULL)
3906: return 0;
3907: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3908: allowed_open->port_to_connect != requestedport)
3909: return 0;
1.351 dtucker 3910: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3911: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3912: return 0;
3913: return 1;
3914: }
3915:
3916: /*
1.336 millert 3917: * Note that in the listen host/port case
1.333 markus 3918: * we don't support FWD_PERMIT_ANY_PORT and
3919: * need to translate between the configured-host (listen_host)
3920: * and what we've sent to the remote server (channel_rfwd_bind_host)
3921: */
3922: static int
1.381 djm 3923: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 3924: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3925: {
3926: const char *allowed_host;
3927:
3928: if (allowed_open->host_to_connect == NULL)
3929: return 0;
3930: if (allowed_open->listen_port != requestedport)
3931: return 0;
1.335 djm 3932: if (!translate && allowed_open->listen_host == NULL &&
3933: requestedhost == NULL)
3934: return 1;
1.333 markus 3935: allowed_host = translate ?
3936: channel_rfwd_bind_host(allowed_open->listen_host) :
3937: allowed_open->listen_host;
1.382 djm 3938: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 3939: strcmp(allowed_host, requestedhost) != 0)
3940: return 0;
3941: return 1;
3942: }
3943:
1.336 millert 3944: static int
1.381 djm 3945: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 3946: const char *requestedpath)
3947: {
3948: if (allowed_open->host_to_connect == NULL)
3949: return 0;
3950: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3951: return 0;
3952: if (allowed_open->listen_path == NULL ||
3953: strcmp(allowed_open->listen_path, requestedpath) != 0)
3954: return 0;
3955: return 1;
3956: }
3957:
1.27 markus 3958: /*
1.208 deraadt 3959: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3960: * local side.
3961: */
1.336 millert 3962: static int
1.367 djm 3963: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
3964: const char *host, u_short port)
1.202 djm 3965: {
1.367 djm 3966: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 3967: struct permission_set *pset = &sc->local_perms;
1.367 djm 3968: int r;
3969: u_int i;
1.397 markus 3970: struct permission *perm = NULL;
1.202 djm 3971:
1.381 djm 3972: for (i = 0; i < pset->num_permitted_user; i++) {
3973: perm = &pset->permitted_user[i];
3974: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 3975: break;
1.381 djm 3976: perm = NULL;
1.202 djm 3977: }
1.381 djm 3978: if (perm == NULL) {
1.202 djm 3979: debug("%s: requested forward not found", __func__);
1.312 djm 3980: return -1;
1.202 djm 3981: }
1.367 djm 3982: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3983: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
3984: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3985: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
3986: (r = sshpkt_put_u32(ssh, port)) != 0 ||
3987: (r = sshpkt_send(ssh)) != 0)
3988: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3989:
1.381 djm 3990: fwd_perm_clear(perm); /* unregister */
1.336 millert 3991:
3992: return 0;
3993: }
3994:
3995: /*
3996: * Request cancellation of remote forwarding of Unix domain socket
3997: * path from local side.
3998: */
3999: static int
1.367 djm 4000: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 4001: {
1.367 djm 4002: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4003: struct permission_set *pset = &sc->local_perms;
1.367 djm 4004: int r;
4005: u_int i;
1.397 markus 4006: struct permission *perm = NULL;
1.336 millert 4007:
1.381 djm 4008: for (i = 0; i < pset->num_permitted_user; i++) {
4009: perm = &pset->permitted_user[i];
4010: if (open_listen_match_streamlocal(perm, path))
1.336 millert 4011: break;
1.381 djm 4012: perm = NULL;
1.336 millert 4013: }
1.381 djm 4014: if (perm == NULL) {
1.336 millert 4015: debug("%s: requested forward not found", __func__);
4016: return -1;
4017: }
1.367 djm 4018: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4019: (r = sshpkt_put_cstring(ssh,
4020: "cancel-streamlocal-forward@openssh.com")) != 0 ||
4021: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4022: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
4023: (r = sshpkt_send(ssh)) != 0)
4024: fatal("%s: send cancel: %s", __func__, ssh_err(r));
4025:
1.381 djm 4026: fwd_perm_clear(perm); /* unregister */
1.312 djm 4027:
4028: return 0;
1.202 djm 4029: }
4030:
4031: /*
1.336 millert 4032: * Request cancellation of remote forwarding of a connection from local side.
4033: */
4034: int
1.367 djm 4035: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 4036: {
4037: if (fwd->listen_path != NULL) {
1.367 djm 4038: return channel_request_rforward_cancel_streamlocal(ssh,
4039: fwd->listen_path);
1.336 millert 4040: } else {
1.367 djm 4041: return channel_request_rforward_cancel_tcpip(ssh,
4042: fwd->listen_host,
4043: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 4044: }
1.1 deraadt 4045: }
4046:
1.99 markus 4047: /*
1.381 djm 4048: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 4049: * usually called by the server, because the user could connect to any port
4050: * anyway, and the server has no way to know but to trust the client anyway.
4051: */
4052: void
1.381 djm 4053: channel_permit_all(struct ssh *ssh, int where)
4054: {
4055: struct permission_set *pset = permission_set_get(ssh, where);
4056:
4057: if (pset->num_permitted_user == 0)
4058: pset->all_permitted = 1;
4059: }
4060:
4061: /*
4062: * Permit the specified host/port for forwarding.
4063: */
4064: void
4065: channel_add_permission(struct ssh *ssh, int who, int where,
4066: char *host, int port)
4067: {
4068: int local = where == FORWARD_LOCAL;
4069: struct permission_set *pset = permission_set_get(ssh, where);
4070:
4071: debug("allow %s forwarding to host %s port %d",
4072: fwd_ident(who, where), host, port);
4073: /*
4074: * Remote forwards set listen_host/port, local forwards set
4075: * host/port_to_connect.
4076: */
4077: permission_set_add(ssh, who, where,
4078: local ? host : 0, local ? port : 0,
4079: local ? NULL : host, NULL, local ? 0 : port, NULL);
4080: pset->all_permitted = 0;
4081: }
4082:
4083: /*
4084: * Administratively disable forwarding.
4085: */
4086: void
4087: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4088: {
1.381 djm 4089: channel_clear_permission(ssh, FORWARD_ADM, where);
4090: permission_set_add(ssh, FORWARD_ADM, where,
4091: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4092: }
4093:
1.381 djm 4094: /*
4095: * Clear a list of permitted opens.
4096: */
1.101 markus 4097: void
1.381 djm 4098: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4099: {
1.381 djm 4100: struct permission **permp;
4101: u_int *npermp;
1.367 djm 4102:
1.381 djm 4103: permission_set_get_array(ssh, who, where, &permp, &npermp);
4104: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4105: *npermp = 0;
1.315 markus 4106: }
4107:
4108: /*
4109: * Update the listen port for a dynamic remote forward, after
4110: * the actual 'newport' has been allocated. If 'newport' < 0 is
4111: * passed then they entry will be invalidated.
4112: */
4113: void
1.381 djm 4114: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4115: {
1.381 djm 4116: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4117:
1.381 djm 4118: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
4119: debug("%s: index out of range: %d num_permitted_user %d",
4120: __func__, idx, pset->num_permitted_user);
1.315 markus 4121: return;
4122: }
4123: debug("%s allowed port %d for forwarding to host %s port %d",
4124: newport > 0 ? "Updating" : "Removing",
4125: newport,
1.381 djm 4126: pset->permitted_user[idx].host_to_connect,
4127: pset->permitted_user[idx].port_to_connect);
1.367 djm 4128: if (newport <= 0)
1.381 djm 4129: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4130: else {
1.381 djm 4131: pset->permitted_user[idx].listen_port =
1.315 markus 4132: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
4133: }
1.99 markus 4134: }
4135:
1.314 dtucker 4136: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4137: int
4138: permitopen_port(const char *p)
4139: {
4140: int port;
4141:
4142: if (strcmp(p, "*") == 0)
4143: return FWD_PERMIT_ANY_PORT;
4144: if ((port = a2port(p)) > 0)
4145: return port;
4146: return -1;
4147: }
4148:
1.276 djm 4149: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4150: static int
1.276 djm 4151: connect_next(struct channel_connect *cctx)
1.41 markus 4152: {
1.276 djm 4153: int sock, saved_errno;
1.336 millert 4154: struct sockaddr_un *sunaddr;
1.367 djm 4155: char ntop[NI_MAXHOST];
4156: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4157:
1.276 djm 4158: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4159: switch (cctx->ai->ai_family) {
4160: case AF_UNIX:
4161: /* unix:pathname instead of host:port */
4162: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4163: strlcpy(ntop, "unix", sizeof(ntop));
4164: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4165: break;
4166: case AF_INET:
4167: case AF_INET6:
4168: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4169: ntop, sizeof(ntop), strport, sizeof(strport),
4170: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
4171: error("connect_next: getnameinfo failed");
4172: continue;
4173: }
4174: break;
4175: default:
1.41 markus 4176: continue;
4177: }
1.300 dtucker 4178: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4179: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4180: if (cctx->ai->ai_next == NULL)
1.186 djm 4181: error("socket: %.100s", strerror(errno));
4182: else
4183: verbose("socket: %.100s", strerror(errno));
1.41 markus 4184: continue;
4185: }
1.205 djm 4186: if (set_nonblock(sock) == -1)
4187: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 4188: if (connect(sock, cctx->ai->ai_addr,
4189: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
4190: debug("connect_next: host %.100s ([%.100s]:%s): "
4191: "%.100s", cctx->host, ntop, strport,
1.41 markus 4192: strerror(errno));
1.276 djm 4193: saved_errno = errno;
1.41 markus 4194: close(sock);
1.276 djm 4195: errno = saved_errno;
1.89 stevesk 4196: continue; /* fail -- try next */
1.41 markus 4197: }
1.336 millert 4198: if (cctx->ai->ai_family != AF_UNIX)
4199: set_nodelay(sock);
1.276 djm 4200: debug("connect_next: host %.100s ([%.100s]:%s) "
4201: "in progress, fd=%d", cctx->host, ntop, strport, sock);
4202: cctx->ai = cctx->ai->ai_next;
4203: return sock;
4204: }
4205: return -1;
4206: }
1.41 markus 4207:
1.276 djm 4208: static void
4209: channel_connect_ctx_free(struct channel_connect *cctx)
4210: {
1.321 djm 4211: free(cctx->host);
1.336 millert 4212: if (cctx->aitop) {
4213: if (cctx->aitop->ai_family == AF_UNIX)
4214: free(cctx->aitop);
4215: else
4216: freeaddrinfo(cctx->aitop);
4217: }
1.329 tedu 4218: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4219: }
4220:
1.357 dtucker 4221: /*
1.372 markus 4222: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4223: * passing back the failure reason if appropriate.
4224: */
1.372 markus 4225: static int
4226: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4227: char *ctype, char *rname, struct channel_connect *cctx,
4228: int *reason, const char **errmsg)
1.276 djm 4229: {
4230: struct addrinfo hints;
4231: int gaierr;
4232: int sock = -1;
4233: char strport[NI_MAXSERV];
1.336 millert 4234:
4235: if (port == PORT_STREAMLOCAL) {
4236: struct sockaddr_un *sunaddr;
4237: struct addrinfo *ai;
4238:
4239: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4240: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4241: return -1;
1.336 millert 4242: }
4243:
4244: /*
4245: * Fake up a struct addrinfo for AF_UNIX connections.
4246: * channel_connect_ctx_free() must check ai_family
4247: * and use free() not freeaddirinfo() for AF_UNIX.
4248: */
4249: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4250: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4251: ai->ai_addr = (struct sockaddr *)(ai + 1);
4252: ai->ai_addrlen = sizeof(*sunaddr);
4253: ai->ai_family = AF_UNIX;
1.372 markus 4254: ai->ai_socktype = socktype;
1.336 millert 4255: ai->ai_protocol = PF_UNSPEC;
4256: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4257: sunaddr->sun_family = AF_UNIX;
4258: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4259: cctx->aitop = ai;
1.336 millert 4260: } else {
4261: memset(&hints, 0, sizeof(hints));
1.367 djm 4262: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4263: hints.ai_socktype = socktype;
1.336 millert 4264: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4265: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4266: != 0) {
4267: if (errmsg != NULL)
4268: *errmsg = ssh_gai_strerror(gaierr);
4269: if (reason != NULL)
4270: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4271: error("connect_to %.100s: unknown host (%s)", name,
4272: ssh_gai_strerror(gaierr));
1.372 markus 4273: return -1;
1.336 millert 4274: }
1.41 markus 4275: }
1.276 djm 4276:
1.372 markus 4277: cctx->host = xstrdup(name);
4278: cctx->port = port;
4279: cctx->ai = cctx->aitop;
1.276 djm 4280:
1.372 markus 4281: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4282: error("connect to %.100s port %d failed: %s",
1.336 millert 4283: name, port, strerror(errno));
1.372 markus 4284: return -1;
4285: }
4286:
4287: return sock;
4288: }
4289:
4290: /* Return CONNECTING channel to remote host:port or local socket path */
4291: static Channel *
4292: connect_to(struct ssh *ssh, const char *host, int port,
4293: char *ctype, char *rname)
4294: {
4295: struct channel_connect cctx;
4296: Channel *c;
4297: int sock;
4298:
4299: memset(&cctx, 0, sizeof(cctx));
4300: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4301: &cctx, NULL, NULL);
4302: if (sock == -1) {
1.276 djm 4303: channel_connect_ctx_free(&cctx);
4304: return NULL;
1.41 markus 4305: }
1.367 djm 4306: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4307: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4308: c->host_port = port;
4309: c->path = xstrdup(host);
1.276 djm 4310: c->connect_ctx = cctx;
1.372 markus 4311:
1.276 djm 4312: return c;
1.41 markus 4313: }
1.99 markus 4314:
1.354 markus 4315: /*
4316: * returns either the newly connected channel or the downstream channel
4317: * that needs to deal with this connection.
4318: */
1.276 djm 4319: Channel *
1.367 djm 4320: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4321: u_short listen_port, char *ctype, char *rname)
1.73 markus 4322: {
1.367 djm 4323: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4324: struct permission_set *pset = &sc->local_perms;
1.367 djm 4325: u_int i;
1.381 djm 4326: struct permission *perm;
1.99 markus 4327:
1.381 djm 4328: for (i = 0; i < pset->num_permitted_user; i++) {
4329: perm = &pset->permitted_user[i];
4330: if (open_listen_match_tcpip(perm,
4331: listen_host, listen_port, 1)) {
4332: if (perm->downstream)
4333: return perm->downstream;
4334: if (perm->port_to_connect == 0)
1.372 markus 4335: return rdynamic_connect_prepare(ssh,
4336: ctype, rname);
1.367 djm 4337: return connect_to(ssh,
1.381 djm 4338: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4339: ctype, rname);
1.276 djm 4340: }
4341: }
1.74 markus 4342: error("WARNING: Server requests forwarding for unknown listen_port %d",
4343: listen_port);
1.276 djm 4344: return NULL;
1.73 markus 4345: }
4346:
1.336 millert 4347: Channel *
1.367 djm 4348: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4349: char *ctype, char *rname)
1.336 millert 4350: {
1.367 djm 4351: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4352: struct permission_set *pset = &sc->local_perms;
1.367 djm 4353: u_int i;
1.381 djm 4354: struct permission *perm;
1.336 millert 4355:
1.381 djm 4356: for (i = 0; i < pset->num_permitted_user; i++) {
4357: perm = &pset->permitted_user[i];
4358: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4359: return connect_to(ssh,
1.381 djm 4360: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4361: ctype, rname);
1.336 millert 4362: }
4363: }
4364: error("WARNING: Server requests forwarding for unknown path %.100s",
4365: path);
4366: return NULL;
4367: }
4368:
1.99 markus 4369: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4370: Channel *
1.367 djm 4371: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4372: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4373: {
1.367 djm 4374: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4375: struct permission_set *pset = &sc->local_perms;
1.372 markus 4376: struct channel_connect cctx;
4377: Channel *c;
1.367 djm 4378: u_int i, permit, permit_adm = 1;
1.372 markus 4379: int sock;
1.381 djm 4380: struct permission *perm;
1.99 markus 4381:
1.381 djm 4382: permit = pset->all_permitted;
1.99 markus 4383: if (!permit) {
1.381 djm 4384: for (i = 0; i < pset->num_permitted_user; i++) {
4385: perm = &pset->permitted_user[i];
4386: if (open_match(perm, host, port)) {
1.99 markus 4387: permit = 1;
1.333 markus 4388: break;
4389: }
1.367 djm 4390: }
1.257 dtucker 4391: }
1.99 markus 4392:
1.381 djm 4393: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4394: permit_adm = 0;
1.381 djm 4395: for (i = 0; i < pset->num_permitted_admin; i++) {
4396: perm = &pset->permitted_admin[i];
4397: if (open_match(perm, host, port)) {
1.257 dtucker 4398: permit_adm = 1;
1.333 markus 4399: break;
4400: }
1.367 djm 4401: }
1.99 markus 4402: }
1.257 dtucker 4403:
4404: if (!permit || !permit_adm) {
1.391 florian 4405: logit("Received request from %.100s port %d to connect to "
4406: "host %.100s port %d, but the request was denied.",
4407: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4408: if (reason != NULL)
4409: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4410: return NULL;
1.99 markus 4411: }
1.372 markus 4412:
4413: memset(&cctx, 0, sizeof(cctx));
4414: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4415: &cctx, reason, errmsg);
4416: if (sock == -1) {
4417: channel_connect_ctx_free(&cctx);
4418: return NULL;
4419: }
4420:
4421: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4422: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4423: c->host_port = port;
4424: c->path = xstrdup(host);
4425: c->connect_ctx = cctx;
4426:
4427: return c;
1.336 millert 4428: }
4429:
4430: /* Check if connecting to that path is permitted and connect. */
4431: Channel *
1.367 djm 4432: channel_connect_to_path(struct ssh *ssh, const char *path,
4433: char *ctype, char *rname)
1.336 millert 4434: {
1.367 djm 4435: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4436: struct permission_set *pset = &sc->local_perms;
1.367 djm 4437: u_int i, permit, permit_adm = 1;
1.381 djm 4438: struct permission *perm;
1.336 millert 4439:
1.381 djm 4440: permit = pset->all_permitted;
1.336 millert 4441: if (!permit) {
1.381 djm 4442: for (i = 0; i < pset->num_permitted_user; i++) {
4443: perm = &pset->permitted_user[i];
4444: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4445: permit = 1;
4446: break;
4447: }
1.367 djm 4448: }
1.336 millert 4449: }
4450:
1.381 djm 4451: if (pset->num_permitted_admin > 0) {
1.336 millert 4452: permit_adm = 0;
1.381 djm 4453: for (i = 0; i < pset->num_permitted_admin; i++) {
4454: perm = &pset->permitted_admin[i];
4455: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4456: permit_adm = 1;
4457: break;
4458: }
1.367 djm 4459: }
1.336 millert 4460: }
4461:
4462: if (!permit || !permit_adm) {
4463: logit("Received request to connect to path %.100s, "
4464: "but the request was denied.", path);
4465: return NULL;
4466: }
1.367 djm 4467: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4468: }
4469:
4470: void
1.367 djm 4471: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4472: {
1.367 djm 4473: struct ssh_channels *sc = ssh->chanctxt;
4474: struct winsize ws;
4475: int r;
1.209 avsm 4476: u_int i;
1.204 djm 4477:
1.367 djm 4478: for (i = 0; i < sc->channels_alloc; i++) {
4479: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4480: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4481: continue;
1.393 deraadt 4482: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4483: continue;
1.367 djm 4484: channel_request_start(ssh, i, "window-change", 0);
4485: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4486: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4487: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4488: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4489: (r = sshpkt_send(ssh)) != 0)
4490: fatal("%s: channel %u: send window-change: %s",
4491: __func__, i, ssh_err(r));
1.204 djm 4492: }
1.372 markus 4493: }
4494:
4495: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4496: static Channel *
4497: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4498: {
4499: Channel *c;
4500: int r;
4501:
4502: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4503: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4504: c->host_port = 0;
4505: c->path = NULL;
4506:
4507: /*
4508: * We need to open the channel before we have a FD,
4509: * so that we can get SOCKS header from peer.
4510: */
4511: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4512: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4513: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4514: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
4515: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
4516: fatal("%s: channel %i: confirm: %s", __func__,
4517: c->self, ssh_err(r));
4518: }
4519: return c;
4520: }
4521:
4522: /* Return CONNECTING socket to remote host:port or local socket path */
4523: static int
4524: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4525: {
4526: struct channel_connect cctx;
4527: int sock;
4528:
4529: memset(&cctx, 0, sizeof(cctx));
4530: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4531: NULL, &cctx, NULL, NULL);
4532: if (sock == -1)
4533: channel_connect_ctx_free(&cctx);
4534: else {
4535: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4536: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4537: c->connect_ctx = cctx;
4538: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4539: }
4540: return sock;
1.99 markus 4541: }
4542:
1.121 markus 4543: /* -- X11 forwarding */
1.1 deraadt 4544:
1.27 markus 4545: /*
4546: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4547: * Returns 0 and a suitable display number for the DISPLAY variable
4548: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4549: */
1.141 stevesk 4550: int
1.367 djm 4551: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4552: int x11_use_localhost, int single_connection,
4553: u_int *display_numberp, int **chanids)
1.1 deraadt 4554: {
1.149 markus 4555: Channel *nc = NULL;
1.31 markus 4556: int display_number, sock;
4557: u_short port;
1.35 markus 4558: struct addrinfo hints, *ai, *aitop;
4559: char strport[NI_MAXSERV];
4560: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4561:
1.224 markus 4562: if (chanids == NULL)
4563: return -1;
4564:
1.33 markus 4565: for (display_number = x11_display_offset;
1.148 deraadt 4566: display_number < MAX_DISPLAYS;
4567: display_number++) {
1.25 markus 4568: port = 6000 + display_number;
1.35 markus 4569: memset(&hints, 0, sizeof(hints));
1.367 djm 4570: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4571: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4572: hints.ai_socktype = SOCK_STREAM;
4573: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4574: if ((gaierr = getaddrinfo(NULL, strport,
4575: &hints, &aitop)) != 0) {
1.271 dtucker 4576: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4577: return -1;
1.25 markus 4578: }
1.35 markus 4579: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4580: if (ai->ai_family != AF_INET &&
4581: ai->ai_family != AF_INET6)
1.35 markus 4582: continue;
1.300 dtucker 4583: sock = socket(ai->ai_family, ai->ai_socktype,
4584: ai->ai_protocol);
1.393 deraadt 4585: if (sock == -1) {
1.35 markus 4586: error("socket: %.100s", strerror(errno));
1.203 markus 4587: freeaddrinfo(aitop);
1.141 stevesk 4588: return -1;
1.35 markus 4589: }
1.376 djm 4590: set_reuseaddr(sock);
1.393 deraadt 4591: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 4592: debug2("%s: bind port %d: %.100s", __func__,
4593: port, strerror(errno));
1.35 markus 4594: close(sock);
1.367 djm 4595: for (n = 0; n < num_socks; n++)
1.35 markus 4596: close(socks[n]);
4597: num_socks = 0;
4598: break;
4599: }
4600: socks[num_socks++] = sock;
4601: if (num_socks == NUM_SOCKS)
4602: break;
1.25 markus 4603: }
1.83 stevesk 4604: freeaddrinfo(aitop);
1.35 markus 4605: if (num_socks > 0)
4606: break;
1.25 markus 4607: }
4608: if (display_number >= MAX_DISPLAYS) {
4609: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4610: return -1;
1.25 markus 4611: }
4612: /* Start listening for connections on the socket. */
1.35 markus 4613: for (n = 0; n < num_socks; n++) {
4614: sock = socks[n];
1.393 deraadt 4615: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 4616: error("listen: %.100s", strerror(errno));
4617: close(sock);
1.141 stevesk 4618: return -1;
1.35 markus 4619: }
1.25 markus 4620: }
1.35 markus 4621:
4622: /* Allocate a channel for each socket. */
1.242 djm 4623: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4624: for (n = 0; n < num_socks; n++) {
4625: sock = socks[n];
1.367 djm 4626: nc = channel_new(ssh, "x11 listener",
1.51 markus 4627: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4628: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4629: 0, "X11 inet listener", 1);
1.167 markus 4630: nc->single_connection = single_connection;
1.224 markus 4631: (*chanids)[n] = nc->self;
1.35 markus 4632: }
1.224 markus 4633: (*chanids)[n] = -1;
1.1 deraadt 4634:
1.141 stevesk 4635: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4636: *display_numberp = display_number;
1.367 djm 4637: return 0;
1.1 deraadt 4638: }
4639:
1.127 itojun 4640: static int
1.77 markus 4641: connect_local_xsocket(u_int dnr)
1.1 deraadt 4642: {
1.25 markus 4643: int sock;
4644: struct sockaddr_un addr;
4645:
1.147 stevesk 4646: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 deraadt 4647: if (sock == -1)
1.147 stevesk 4648: error("socket: %.100s", strerror(errno));
4649: memset(&addr, 0, sizeof(addr));
4650: addr.sun_family = AF_UNIX;
4651: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4652: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4653: return sock;
4654: close(sock);
1.25 markus 4655: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4656: return -1;
1.1 deraadt 4657: }
4658:
1.51 markus 4659: int
1.367 djm 4660: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4661: {
1.248 deraadt 4662: u_int display_number;
1.25 markus 4663: const char *display;
1.51 markus 4664: char buf[1024], *cp;
1.35 markus 4665: struct addrinfo hints, *ai, *aitop;
4666: char strport[NI_MAXSERV];
1.248 deraadt 4667: int gaierr, sock = 0;
1.25 markus 4668:
4669: /* Try to open a socket for the local X server. */
4670: display = getenv("DISPLAY");
4671: if (!display) {
4672: error("DISPLAY not set.");
1.51 markus 4673: return -1;
1.25 markus 4674: }
1.27 markus 4675: /*
4676: * Now we decode the value of the DISPLAY variable and make a
4677: * connection to the real X server.
4678: */
4679:
4680: /*
4681: * Check if it is a unix domain socket. Unix domain displays are in
4682: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4683: */
1.25 markus 4684: if (strncmp(display, "unix:", 5) == 0 ||
4685: display[0] == ':') {
4686: /* Connect to the unix domain socket. */
1.367 djm 4687: if (sscanf(strrchr(display, ':') + 1, "%u",
4688: &display_number) != 1) {
4689: error("Could not parse display number from DISPLAY: "
4690: "%.100s", display);
1.51 markus 4691: return -1;
1.25 markus 4692: }
4693: /* Create a socket. */
4694: sock = connect_local_xsocket(display_number);
4695: if (sock < 0)
1.51 markus 4696: return -1;
1.25 markus 4697:
4698: /* OK, we now have a connection to the display. */
1.51 markus 4699: return sock;
1.25 markus 4700: }
1.27 markus 4701: /*
4702: * Connect to an inet socket. The DISPLAY value is supposedly
4703: * hostname:d[.s], where hostname may also be numeric IP address.
4704: */
1.145 stevesk 4705: strlcpy(buf, display, sizeof(buf));
1.25 markus 4706: cp = strchr(buf, ':');
4707: if (!cp) {
4708: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4709: return -1;
1.25 markus 4710: }
4711: *cp = 0;
1.367 djm 4712: /*
4713: * buf now contains the host name. But first we parse the
4714: * display number.
4715: */
1.248 deraadt 4716: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4717: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4718: display);
1.51 markus 4719: return -1;
1.25 markus 4720: }
1.35 markus 4721:
4722: /* Look up the host address */
4723: memset(&hints, 0, sizeof(hints));
1.367 djm 4724: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4725: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4726: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4727: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4728: error("%.100s: unknown host. (%s)", buf,
4729: ssh_gai_strerror(gaierr));
1.51 markus 4730: return -1;
1.25 markus 4731: }
1.35 markus 4732: for (ai = aitop; ai; ai = ai->ai_next) {
4733: /* Create a socket. */
1.300 dtucker 4734: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 4735: if (sock == -1) {
1.194 markus 4736: debug2("socket: %.100s", strerror(errno));
1.41 markus 4737: continue;
4738: }
4739: /* Connect it to the display. */
1.393 deraadt 4740: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 4741: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4742: 6000 + display_number, strerror(errno));
4743: close(sock);
4744: continue;
4745: }
4746: /* Success */
4747: break;
1.35 markus 4748: }
4749: freeaddrinfo(aitop);
4750: if (!ai) {
1.367 djm 4751: error("connect %.100s port %u: %.100s", buf,
4752: 6000 + display_number, strerror(errno));
1.51 markus 4753: return -1;
1.25 markus 4754: }
1.162 stevesk 4755: set_nodelay(sock);
1.51 markus 4756: return sock;
4757: }
4758:
4759: /*
1.27 markus 4760: * Requests forwarding of X11 connections, generates fake authentication
4761: * data, and enables authentication spoofing.
1.121 markus 4762: * This should be called in the client only.
1.27 markus 4763: */
1.49 markus 4764: void
1.367 djm 4765: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4766: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4767: {
1.367 djm 4768: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4769: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4770: u_int i, value;
1.367 djm 4771: const char *cp;
1.25 markus 4772: char *new_data;
1.367 djm 4773: int r, screen_number;
1.25 markus 4774:
1.367 djm 4775: if (sc->x11_saved_display == NULL)
4776: sc->x11_saved_display = xstrdup(disp);
4777: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4778: error("x11_request_forwarding_with_spoofing: different "
4779: "$DISPLAY already forwarded");
4780: return;
4781: }
4782:
1.266 djm 4783: cp = strchr(disp, ':');
1.25 markus 4784: if (cp)
4785: cp = strchr(cp, '.');
4786: if (cp)
1.245 deraadt 4787: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4788: else
4789: screen_number = 0;
4790:
1.367 djm 4791: if (sc->x11_saved_proto == NULL) {
1.219 djm 4792: /* Save protocol name. */
1.367 djm 4793: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4794:
4795: /* Extract real authentication data. */
1.367 djm 4796: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4797: for (i = 0; i < data_len; i++) {
4798: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4799: fatal("x11_request_forwarding: bad "
4800: "authentication data: %.100s", data);
1.367 djm 4801: sc->x11_saved_data[i] = value;
1.219 djm 4802: }
1.367 djm 4803: sc->x11_saved_data_len = data_len;
1.353 natano 4804:
4805: /* Generate fake data of the same length. */
1.367 djm 4806: sc->x11_fake_data = xmalloc(data_len);
4807: arc4random_buf(sc->x11_fake_data, data_len);
4808: sc->x11_fake_data_len = data_len;
1.25 markus 4809: }
4810:
4811: /* Convert the fake data into hex. */
1.367 djm 4812: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 4813:
4814: /* Send the request packet. */
1.367 djm 4815: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4816: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4817: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4818: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4819: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4820: (r = sshpkt_send(ssh)) != 0 ||
4821: (r = ssh_packet_write_wait(ssh)) != 0)
4822: fatal("%s: send x11-req: %s", __func__, ssh_err(r));
1.321 djm 4823: free(new_data);
1.1 deraadt 4824: }
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