Annotation of src/usr.bin/ssh/channels.c, Revision 1.401
1.401 ! djm 1: /* $OpenBSD: channels.c,v 1.400 2020/07/03 07:17:35 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;
1.25 markus 347:
348: /* Try to find a free slot where to put the new channel. */
1.367 djm 349: for (i = 0; i < sc->channels_alloc; i++) {
350: if (sc->channels[i] == NULL) {
1.25 markus 351: /* Found a free slot. */
1.367 djm 352: found = i;
1.25 markus 353: break;
354: }
1.367 djm 355: }
356: if (i >= sc->channels_alloc) {
357: /*
358: * There are no free slots. Take last+1 slot and expand
359: * the array.
360: */
361: found = sc->channels_alloc;
362: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
363: fatal("%s: internal error: channels_alloc %d too big",
364: __func__, sc->channels_alloc);
365: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
366: sc->channels_alloc + 10, sizeof(*sc->channels));
367: sc->channels_alloc += 10;
368: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 369: }
1.113 markus 370: /* Initialize and return new channel. */
1.367 djm 371: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
372: if ((c->input = sshbuf_new()) == NULL ||
373: (c->output = sshbuf_new()) == NULL ||
374: (c->extended = sshbuf_new()) == NULL)
375: fatal("%s: sshbuf_new failed", __func__);
1.159 markus 376: c->ostate = CHAN_OUTPUT_OPEN;
377: c->istate = CHAN_INPUT_OPEN;
1.367 djm 378: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 379: c->self = found;
380: c->type = type;
1.41 markus 381: c->ctype = ctype;
1.51 markus 382: c->local_window = window;
383: c->local_window_max = window;
384: c->local_maxpacket = maxpack;
1.190 markus 385: c->remote_name = xstrdup(remote_name);
1.302 djm 386: c->ctl_chan = -1;
1.299 markus 387: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 388: TAILQ_INIT(&c->status_confirms);
1.25 markus 389: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 390: return c;
1.1 deraadt 391: }
1.52 markus 392:
1.367 djm 393: static void
394: channel_find_maxfd(struct ssh_channels *sc)
1.132 markus 395: {
1.209 avsm 396: u_int i;
397: int max = 0;
1.132 markus 398: Channel *c;
399:
1.367 djm 400: for (i = 0; i < sc->channels_alloc; i++) {
401: c = sc->channels[i];
1.132 markus 402: if (c != NULL) {
1.352 deraadt 403: max = MAXIMUM(max, c->rfd);
404: max = MAXIMUM(max, c->wfd);
405: max = MAXIMUM(max, c->efd);
1.132 markus 406: }
407: }
1.367 djm 408: sc->channel_max_fd = max;
1.132 markus 409: }
410:
411: int
1.367 djm 412: channel_close_fd(struct ssh *ssh, int *fdp)
1.132 markus 413: {
1.367 djm 414: struct ssh_channels *sc = ssh->chanctxt;
1.132 markus 415: int ret = 0, fd = *fdp;
416:
417: if (fd != -1) {
418: ret = close(fd);
419: *fdp = -1;
1.367 djm 420: if (fd == sc->channel_max_fd)
421: channel_find_maxfd(sc);
1.132 markus 422: }
423: return ret;
424: }
425:
1.52 markus 426: /* Close all channel fd/socket. */
1.127 itojun 427: static void
1.367 djm 428: channel_close_fds(struct ssh *ssh, Channel *c)
429: {
1.379 tb 430: int sock = c->sock, rfd = c->rfd, wfd = c->wfd, efd = c->efd;
431:
1.367 djm 432: channel_close_fd(ssh, &c->sock);
1.379 tb 433: if (rfd != sock)
434: channel_close_fd(ssh, &c->rfd);
435: if (wfd != sock && wfd != rfd)
436: channel_close_fd(ssh, &c->wfd);
437: if (efd != sock && efd != rfd && efd != wfd)
438: channel_close_fd(ssh, &c->efd);
1.367 djm 439: }
440:
441: static void
1.381 djm 442: fwd_perm_clear(struct permission *perm)
1.52 markus 443: {
1.381 djm 444: free(perm->host_to_connect);
445: free(perm->listen_host);
446: free(perm->listen_path);
1.398 dtucker 447: memset(perm, 0, sizeof(*perm));
1.367 djm 448: }
449:
1.381 djm 450: /* Returns an printable name for the specified forwarding permission list */
451: static const char *
452: fwd_ident(int who, int where)
453: {
454: if (who == FORWARD_ADM) {
455: if (where == FORWARD_LOCAL)
456: return "admin local";
457: else if (where == FORWARD_REMOTE)
458: return "admin remote";
459: } else if (who == FORWARD_USER) {
460: if (where == FORWARD_LOCAL)
461: return "user local";
462: else if (where == FORWARD_REMOTE)
463: return "user remote";
464: }
465: fatal("Unknown forward permission list %d/%d", who, where);
466: }
467:
468: /* Returns the forwarding permission list for the specified direction */
469: static struct permission_set *
470: permission_set_get(struct ssh *ssh, int where)
471: {
472: struct ssh_channels *sc = ssh->chanctxt;
1.367 djm 473:
1.381 djm 474: switch (where) {
475: case FORWARD_LOCAL:
476: return &sc->local_perms;
477: break;
478: case FORWARD_REMOTE:
479: return &sc->remote_perms;
480: break;
481: default:
482: fatal("%s: invalid forwarding direction %d", __func__, where);
483: }
484: }
485:
1.392 dtucker 486: /* Returns pointers to the specified forwarding list and its element count */
1.381 djm 487: static void
488: permission_set_get_array(struct ssh *ssh, int who, int where,
489: struct permission ***permpp, u_int **npermpp)
490: {
491: struct permission_set *pset = permission_set_get(ssh, where);
492:
493: switch (who) {
494: case FORWARD_USER:
495: *permpp = &pset->permitted_user;
496: *npermpp = &pset->num_permitted_user;
497: break;
498: case FORWARD_ADM:
499: *permpp = &pset->permitted_admin;
500: *npermpp = &pset->num_permitted_admin;
501: break;
502: default:
503: fatal("%s: invalid forwarding client %d", __func__, who);
504: }
505: }
506:
507: /* Adds an entry to the spcified forwarding list */
1.367 djm 508: static int
1.381 djm 509: permission_set_add(struct ssh *ssh, int who, int where,
1.367 djm 510: const char *host_to_connect, int port_to_connect,
511: const char *listen_host, const char *listen_path, int listen_port,
512: Channel *downstream)
513: {
1.381 djm 514: struct permission **permp;
515: u_int n, *npermp;
1.367 djm 516:
1.381 djm 517: permission_set_get_array(ssh, who, where, &permp, &npermp);
1.367 djm 518:
1.381 djm 519: if (*npermp >= INT_MAX)
520: fatal("%s: %s overflow", __func__, fwd_ident(who, where));
1.367 djm 521:
1.381 djm 522: *permp = xrecallocarray(*permp, *npermp, *npermp + 1, sizeof(**permp));
523: n = (*npermp)++;
1.367 djm 524: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
1.381 djm 525: (*permp)[n].host_to_connect = MAYBE_DUP(host_to_connect);
526: (*permp)[n].port_to_connect = port_to_connect;
527: (*permp)[n].listen_host = MAYBE_DUP(listen_host);
528: (*permp)[n].listen_path = MAYBE_DUP(listen_path);
529: (*permp)[n].listen_port = listen_port;
530: (*permp)[n].downstream = downstream;
1.367 djm 531: #undef MAYBE_DUP
532: return (int)n;
533: }
534:
535: static void
536: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
537: {
538: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 539: struct permission_set *pset = &sc->local_perms;
540: struct permission *perm;
1.367 djm 541: int r;
542: u_int i;
543:
1.381 djm 544: for (i = 0; i < pset->num_permitted_user; i++) {
545: perm = &pset->permitted_user[i];
546: if (perm->downstream != c)
1.367 djm 547: continue;
548:
549: /* cancel on the server, since mux client is gone */
550: debug("channel %d: cleanup remote forward for %s:%u",
1.381 djm 551: c->self, perm->listen_host, perm->listen_port);
1.367 djm 552: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
553: (r = sshpkt_put_cstring(ssh,
554: "cancel-tcpip-forward")) != 0 ||
555: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
556: (r = sshpkt_put_cstring(ssh,
1.381 djm 557: channel_rfwd_bind_host(perm->listen_host))) != 0 ||
558: (r = sshpkt_put_u32(ssh, perm->listen_port)) != 0 ||
1.367 djm 559: (r = sshpkt_send(ssh)) != 0) {
560: fatal("%s: channel %i: %s", __func__,
561: c->self, ssh_err(r));
562: }
1.381 djm 563: fwd_perm_clear(perm); /* unregister */
1.367 djm 564: }
1.121 markus 565: }
566:
567: /* Free the channel and close its fd/socket. */
568: void
1.367 djm 569: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 570: {
1.367 djm 571: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 572: char *s;
1.209 avsm 573: u_int i, n;
1.354 markus 574: Channel *other;
1.275 djm 575: struct channel_confirm *cc;
1.121 markus 576:
1.367 djm 577: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
578: if ((other = sc->channels[i]) == NULL)
579: continue;
580: n++;
581: /* detach from mux client and prepare for closing */
582: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
583: other->type == SSH_CHANNEL_MUX_PROXY &&
584: other->mux_ctx == c) {
585: other->mux_ctx = NULL;
586: other->type = SSH_CHANNEL_OPEN;
587: other->istate = CHAN_INPUT_CLOSED;
588: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 589: }
590: }
1.209 avsm 591: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 592: c->remote_name ? c->remote_name : "???", n);
593:
1.367 djm 594: if (c->type == SSH_CHANNEL_MUX_CLIENT)
595: mux_remove_remote_forwardings(ssh, c);
1.401 ! djm 596: else if (c->type == SSH_CHANNEL_MUX_LISTENER) {
! 597: free(c->mux_ctx);
! 598: c->mux_ctx = NULL;
! 599: }
1.354 markus 600:
1.384 markus 601: if (log_level_get() >= SYSLOG_LEVEL_DEBUG3) {
602: s = channel_open_message(ssh);
603: debug3("channel %d: status: %s", c->self, s);
604: free(s);
605: }
1.121 markus 606:
1.367 djm 607: channel_close_fds(ssh, c);
608: sshbuf_free(c->input);
609: sshbuf_free(c->output);
610: sshbuf_free(c->extended);
611: c->input = c->output = c->extended = NULL;
1.321 djm 612: free(c->remote_name);
613: c->remote_name = NULL;
614: free(c->path);
615: c->path = NULL;
616: free(c->listening_addr);
617: c->listening_addr = NULL;
1.275 djm 618: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
619: if (cc->abandon_cb != NULL)
1.367 djm 620: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 621: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 622: freezero(cc, sizeof(*cc));
1.275 djm 623: }
1.280 djm 624: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 625: c->filter_cleanup(ssh, c->self, c->filter_ctx);
626: sc->channels[c->self] = NULL;
1.396 jsg 627: freezero(c, sizeof(*c));
1.121 markus 628: }
629:
630: void
1.367 djm 631: channel_free_all(struct ssh *ssh)
1.121 markus 632: {
1.209 avsm 633: u_int i;
1.390 dtucker 634: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 635:
1.390 dtucker 636: for (i = 0; i < sc->channels_alloc; i++)
637: if (sc->channels[i] != NULL)
638: channel_free(ssh, sc->channels[i]);
639:
640: free(sc->channels);
641: sc->channels = NULL;
642: sc->channels_alloc = 0;
643: sc->channel_max_fd = 0;
644:
645: free(sc->x11_saved_display);
646: sc->x11_saved_display = NULL;
647:
648: free(sc->x11_saved_proto);
649: sc->x11_saved_proto = NULL;
650:
651: free(sc->x11_saved_data);
652: sc->x11_saved_data = NULL;
653: sc->x11_saved_data_len = 0;
654:
655: free(sc->x11_fake_data);
656: sc->x11_fake_data = NULL;
657: sc->x11_fake_data_len = 0;
1.131 markus 658: }
659:
1.121 markus 660: /*
661: * Closes the sockets/fds of all channels. This is used to close extra file
662: * descriptors after a fork.
663: */
664: void
1.367 djm 665: channel_close_all(struct ssh *ssh)
1.121 markus 666: {
1.209 avsm 667: u_int i;
1.121 markus 668:
1.367 djm 669: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
670: if (ssh->chanctxt->channels[i] != NULL)
671: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 672: }
673:
674: /*
1.131 markus 675: * Stop listening to channels.
676: */
677: void
1.367 djm 678: channel_stop_listening(struct ssh *ssh)
1.131 markus 679: {
1.209 avsm 680: u_int i;
1.131 markus 681: Channel *c;
682:
1.367 djm 683: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
684: c = ssh->chanctxt->channels[i];
1.131 markus 685: if (c != NULL) {
686: switch (c->type) {
687: case SSH_CHANNEL_AUTH_SOCKET:
688: case SSH_CHANNEL_PORT_LISTENER:
689: case SSH_CHANNEL_RPORT_LISTENER:
690: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 691: case SSH_CHANNEL_UNIX_LISTENER:
692: case SSH_CHANNEL_RUNIX_LISTENER:
1.367 djm 693: channel_close_fd(ssh, &c->sock);
694: channel_free(ssh, c);
1.131 markus 695: break;
696: }
697: }
698: }
699: }
700:
701: /*
1.121 markus 702: * Returns true if no channel has too much buffered data, and false if one or
703: * more channel is overfull.
704: */
705: int
1.367 djm 706: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 707: {
708: u_int i;
1.367 djm 709: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 710: Channel *c;
711:
1.367 djm 712: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
713: c = ssh->chanctxt->channels[i];
714: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
715: continue;
716: if (sshbuf_len(c->output) > maxsize) {
717: debug2("channel %d: big output buffer %zu > %u",
718: c->self, sshbuf_len(c->output), maxsize);
719: return 0;
1.121 markus 720: }
721: }
722: return 1;
723: }
724:
725: /* Returns true if any channel is still open. */
726: int
1.367 djm 727: channel_still_open(struct ssh *ssh)
1.121 markus 728: {
1.209 avsm 729: u_int i;
1.121 markus 730: Channel *c;
731:
1.367 djm 732: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
733: c = ssh->chanctxt->channels[i];
1.121 markus 734: if (c == NULL)
735: continue;
736: switch (c->type) {
737: case SSH_CHANNEL_X11_LISTENER:
738: case SSH_CHANNEL_PORT_LISTENER:
739: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 740: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 741: case SSH_CHANNEL_CLOSED:
742: case SSH_CHANNEL_AUTH_SOCKET:
743: case SSH_CHANNEL_DYNAMIC:
1.372 markus 744: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 745: case SSH_CHANNEL_CONNECTING:
746: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 747: case SSH_CHANNEL_ABANDONED:
1.336 millert 748: case SSH_CHANNEL_UNIX_LISTENER:
749: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 750: continue;
751: case SSH_CHANNEL_LARVAL:
752: continue;
753: case SSH_CHANNEL_OPENING:
754: case SSH_CHANNEL_OPEN:
1.372 markus 755: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 756: case SSH_CHANNEL_X11_OPEN:
1.302 djm 757: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 758: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 759: return 1;
760: default:
1.358 djm 761: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 762: /* NOTREACHED */
763: }
764: }
765: return 0;
766: }
767:
768: /* Returns the id of an open channel suitable for keepaliving */
769: int
1.367 djm 770: channel_find_open(struct ssh *ssh)
1.121 markus 771: {
1.209 avsm 772: u_int i;
1.121 markus 773: Channel *c;
774:
1.367 djm 775: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
776: c = ssh->chanctxt->channels[i];
1.368 djm 777: if (c == NULL || !c->have_remote_id)
1.121 markus 778: continue;
779: switch (c->type) {
780: case SSH_CHANNEL_CLOSED:
781: case SSH_CHANNEL_DYNAMIC:
1.372 markus 782: case SSH_CHANNEL_RDYNAMIC_OPEN:
783: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 784: case SSH_CHANNEL_X11_LISTENER:
785: case SSH_CHANNEL_PORT_LISTENER:
786: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 787: case SSH_CHANNEL_MUX_LISTENER:
788: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 789: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 790: case SSH_CHANNEL_OPENING:
791: case SSH_CHANNEL_CONNECTING:
792: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 793: case SSH_CHANNEL_ABANDONED:
1.336 millert 794: case SSH_CHANNEL_UNIX_LISTENER:
795: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 796: continue;
797: case SSH_CHANNEL_LARVAL:
798: case SSH_CHANNEL_AUTH_SOCKET:
799: case SSH_CHANNEL_OPEN:
800: case SSH_CHANNEL_X11_OPEN:
801: return i;
802: default:
1.358 djm 803: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 804: /* NOTREACHED */
805: }
806: }
807: return -1;
808: }
809:
1.385 djm 810: /* Returns the state of the channel's extended usage flag */
811: const char *
812: channel_format_extended_usage(const Channel *c)
813: {
814: if (c->efd == -1)
815: return "closed";
816:
817: switch (c->extended_usage) {
818: case CHAN_EXTENDED_WRITE:
819: return "write";
820: case CHAN_EXTENDED_READ:
821: return "read";
822: case CHAN_EXTENDED_IGNORE:
823: return "ignore";
824: default:
825: return "UNKNOWN";
826: }
827: }
828:
1.386 djm 829: static char *
830: channel_format_status(const Channel *c)
831: {
832: char *ret = NULL;
833:
834: xasprintf(&ret, "t%d %s%u i%u/%zu o%u/%zu e[%s]/%zu "
835: "fd %d/%d/%d sock %d cc %d",
836: c->type,
837: c->have_remote_id ? "r" : "nr", c->remote_id,
838: c->istate, sshbuf_len(c->input),
839: c->ostate, sshbuf_len(c->output),
840: channel_format_extended_usage(c), sshbuf_len(c->extended),
841: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan);
842: return ret;
843: }
844:
1.121 markus 845: /*
846: * Returns a message describing the currently open forwarded connections,
847: * suitable for sending to the client. The message contains crlf pairs for
848: * newlines.
849: */
850: char *
1.367 djm 851: channel_open_message(struct ssh *ssh)
1.121 markus 852: {
1.367 djm 853: struct sshbuf *buf;
1.121 markus 854: Channel *c;
1.209 avsm 855: u_int i;
1.367 djm 856: int r;
1.386 djm 857: char *cp, *ret;
1.121 markus 858:
1.367 djm 859: if ((buf = sshbuf_new()) == NULL)
860: fatal("%s: sshbuf_new", __func__);
861: if ((r = sshbuf_putf(buf,
862: "The following connections are open:\r\n")) != 0)
863: fatal("%s: sshbuf_putf: %s", __func__, ssh_err(r));
864: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
865: c = ssh->chanctxt->channels[i];
1.121 markus 866: if (c == NULL)
867: continue;
868: switch (c->type) {
869: case SSH_CHANNEL_X11_LISTENER:
870: case SSH_CHANNEL_PORT_LISTENER:
871: case SSH_CHANNEL_RPORT_LISTENER:
872: case SSH_CHANNEL_CLOSED:
873: case SSH_CHANNEL_AUTH_SOCKET:
874: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 875: case SSH_CHANNEL_ABANDONED:
1.302 djm 876: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 877: case SSH_CHANNEL_UNIX_LISTENER:
878: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 879: continue;
880: case SSH_CHANNEL_LARVAL:
881: case SSH_CHANNEL_OPENING:
882: case SSH_CHANNEL_CONNECTING:
883: case SSH_CHANNEL_DYNAMIC:
1.372 markus 884: case SSH_CHANNEL_RDYNAMIC_OPEN:
885: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 886: case SSH_CHANNEL_OPEN:
887: case SSH_CHANNEL_X11_OPEN:
1.354 markus 888: case SSH_CHANNEL_MUX_PROXY:
889: case SSH_CHANNEL_MUX_CLIENT:
1.386 djm 890: cp = channel_format_status(c);
891: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
892: c->self, c->remote_name, cp)) != 0) {
893: free(cp);
1.367 djm 894: fatal("%s: sshbuf_putf: %s",
895: __func__, ssh_err(r));
1.386 djm 896: }
897: free(cp);
1.121 markus 898: continue;
899: default:
1.367 djm 900: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 901: /* NOTREACHED */
902: }
903: }
1.367 djm 904: if ((ret = sshbuf_dup_string(buf)) == NULL)
905: fatal("%s: sshbuf_dup_string", __func__);
906: sshbuf_free(buf);
907: return ret;
908: }
909:
910: static void
911: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
912: {
913: int r;
914:
915: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
916: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
917: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
918: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
919: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
920: fatal("%s: channel %i: open: %s", where, c->self, ssh_err(r));
921: }
1.121 markus 922: }
923:
924: void
1.367 djm 925: channel_send_open(struct ssh *ssh, int id)
1.121 markus 926: {
1.367 djm 927: Channel *c = channel_lookup(ssh, id);
928: int r;
1.180 deraadt 929:
1.121 markus 930: if (c == NULL) {
1.188 itojun 931: logit("channel_send_open: %d: bad id", id);
1.121 markus 932: return;
933: }
1.184 markus 934: debug2("channel %d: send open", id);
1.367 djm 935: open_preamble(ssh, __func__, c, c->ctype);
936: if ((r = sshpkt_send(ssh)) != 0)
937: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.121 markus 938: }
939:
940: void
1.367 djm 941: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 942: {
1.367 djm 943: Channel *c = channel_lookup(ssh, id);
944: int r;
1.180 deraadt 945:
1.121 markus 946: if (c == NULL) {
1.367 djm 947: logit("%s: %d: unknown channel id", __func__, id);
1.121 markus 948: return;
949: }
1.368 djm 950: if (!c->have_remote_id)
951: fatal(":%s: channel %d: no remote id", __func__, c->self);
952:
1.204 djm 953: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 954: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
955: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
956: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
957: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
958: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
959: }
1.121 markus 960: }
1.241 deraadt 961:
1.121 markus 962: void
1.367 djm 963: channel_register_status_confirm(struct ssh *ssh, int id,
964: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 965: {
966: struct channel_confirm *cc;
967: Channel *c;
968:
1.367 djm 969: if ((c = channel_lookup(ssh, id)) == NULL)
970: fatal("%s: %d: bad id", __func__, id);
1.275 djm 971:
1.327 djm 972: cc = xcalloc(1, sizeof(*cc));
1.275 djm 973: cc->cb = cb;
974: cc->abandon_cb = abandon_cb;
975: cc->ctx = ctx;
976: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
977: }
978:
979: void
1.367 djm 980: channel_register_open_confirm(struct ssh *ssh, int id,
981: channel_open_fn *fn, void *ctx)
1.121 markus 982: {
1.367 djm 983: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 984:
1.121 markus 985: if (c == NULL) {
1.367 djm 986: logit("%s: %d: bad id", __func__, id);
1.121 markus 987: return;
988: }
1.275 djm 989: c->open_confirm = fn;
990: c->open_confirm_ctx = ctx;
1.121 markus 991: }
1.241 deraadt 992:
1.121 markus 993: void
1.367 djm 994: channel_register_cleanup(struct ssh *ssh, int id,
995: channel_callback_fn *fn, int do_close)
1.121 markus 996: {
1.367 djm 997: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 998:
1.121 markus 999: if (c == NULL) {
1.367 djm 1000: logit("%s: %d: bad id", __func__, id);
1.121 markus 1001: return;
1002: }
1.131 markus 1003: c->detach_user = fn;
1.225 djm 1004: c->detach_close = do_close;
1.121 markus 1005: }
1.241 deraadt 1006:
1.121 markus 1007: void
1.367 djm 1008: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 1009: {
1.367 djm 1010: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1011:
1.121 markus 1012: if (c == NULL) {
1.367 djm 1013: logit("%s: %d: bad id", __func__, id);
1.121 markus 1014: return;
1.52 markus 1015: }
1.131 markus 1016: c->detach_user = NULL;
1.225 djm 1017: c->detach_close = 0;
1.121 markus 1018: }
1.241 deraadt 1019:
1.121 markus 1020: void
1.367 djm 1021: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1022: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1023: {
1.367 djm 1024: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1025:
1.121 markus 1026: if (c == NULL) {
1.367 djm 1027: logit("%s: %d: bad id", __func__, id);
1.121 markus 1028: return;
1.52 markus 1029: }
1.231 reyk 1030: c->input_filter = ifn;
1031: c->output_filter = ofn;
1.279 djm 1032: c->filter_ctx = ctx;
1.280 djm 1033: c->filter_cleanup = cfn;
1.52 markus 1034: }
1035:
1.49 markus 1036: void
1.367 djm 1037: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1038: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1039: {
1.367 djm 1040: Channel *c = channel_lookup(ssh, id);
1041: int r;
1.180 deraadt 1042:
1.121 markus 1043: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1044: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1045: if (!c->have_remote_id)
1046: fatal(":%s: channel %d: no remote id", __func__, c->self);
1047:
1.367 djm 1048: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1049: c->type = SSH_CHANNEL_OPEN;
1.168 markus 1050: c->local_window = c->local_window_max = window_max;
1.367 djm 1051:
1052: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1053: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1054: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1055: (r = sshpkt_send(ssh)) != 0)
1056: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.1 deraadt 1057: }
1058:
1.127 itojun 1059: static void
1.367 djm 1060: channel_pre_listener(struct ssh *ssh, Channel *c,
1061: fd_set *readset, fd_set *writeset)
1.41 markus 1062: {
1063: FD_SET(c->sock, readset);
1064: }
1065:
1.127 itojun 1066: static void
1.367 djm 1067: channel_pre_connecting(struct ssh *ssh, Channel *c,
1068: fd_set *readset, fd_set *writeset)
1.75 markus 1069: {
1070: debug3("channel %d: waiting for connection", c->self);
1071: FD_SET(c->sock, writeset);
1072: }
1073:
1.127 itojun 1074: static void
1.367 djm 1075: channel_pre_open(struct ssh *ssh, Channel *c,
1076: fd_set *readset, fd_set *writeset)
1.41 markus 1077: {
1.44 markus 1078: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1079: c->remote_window > 0 &&
1.367 djm 1080: sshbuf_len(c->input) < c->remote_window &&
1081: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.44 markus 1082: FD_SET(c->rfd, readset);
1083: if (c->ostate == CHAN_OUTPUT_OPEN ||
1084: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1085: if (sshbuf_len(c->output) > 0) {
1.44 markus 1086: FD_SET(c->wfd, writeset);
1087: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1088: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1089: debug2("channel %d: "
1090: "obuf_empty delayed efd %d/(%zu)", c->self,
1091: c->efd, sshbuf_len(c->extended));
1.172 markus 1092: else
1.367 djm 1093: chan_obuf_empty(ssh, c);
1.44 markus 1094: }
1095: }
1096: /** XXX check close conditions, too */
1.358 djm 1097: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1098: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1099: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1100: sshbuf_len(c->extended) > 0)
1.44 markus 1101: FD_SET(c->efd, writeset);
1.306 djm 1102: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1103: (c->extended_usage == CHAN_EXTENDED_READ ||
1104: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1105: sshbuf_len(c->extended) < c->remote_window)
1.44 markus 1106: FD_SET(c->efd, readset);
1107: }
1.204 djm 1108: /* XXX: What about efd? races? */
1.44 markus 1109: }
1110:
1.41 markus 1111: /*
1112: * This is a special state for X11 authentication spoofing. An opened X11
1113: * connection (when authentication spoofing is being done) remains in this
1114: * state until the first packet has been completely read. The authentication
1115: * data in that packet is then substituted by the real data if it matches the
1116: * fake data, and the channel is put into normal mode.
1.51 markus 1117: * XXX All this happens at the client side.
1.121 markus 1118: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1119: */
1.127 itojun 1120: static int
1.367 djm 1121: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1122: {
1.367 djm 1123: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1124: u_char *ucp;
1125: u_int proto_len, data_len;
1.25 markus 1126:
1.347 djm 1127: /* Is this being called after the refusal deadline? */
1.367 djm 1128: if (sc->x11_refuse_time != 0 &&
1129: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1130: verbose("Rejected X11 connection after ForwardX11Timeout "
1131: "expired");
1132: return -1;
1133: }
1134:
1.41 markus 1135: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1136: if (sshbuf_len(b) < 12)
1.41 markus 1137: return 0;
1138:
1139: /* Parse the lengths of variable-length fields. */
1.367 djm 1140: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1141: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1142: proto_len = 256 * ucp[6] + ucp[7];
1143: data_len = 256 * ucp[8] + ucp[9];
1144: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1145: proto_len = ucp[6] + 256 * ucp[7];
1146: data_len = ucp[8] + 256 * ucp[9];
1147: } else {
1.194 markus 1148: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1149: ucp[0]);
1.41 markus 1150: return -1;
1151: }
1152:
1153: /* Check if the whole packet is in buffer. */
1.367 djm 1154: if (sshbuf_len(b) <
1.41 markus 1155: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1156: return 0;
1157:
1158: /* Check if authentication protocol matches. */
1.367 djm 1159: if (proto_len != strlen(sc->x11_saved_proto) ||
1160: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1161: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1162: return -1;
1163: }
1164: /* Check if authentication data matches our fake data. */
1.367 djm 1165: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1166: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1167: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1168: debug2("X11 auth data does not match fake data.");
1.41 markus 1169: return -1;
1170: }
1171: /* Check fake data length */
1.367 djm 1172: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1173: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1174: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1175: return -1;
1176: }
1177: /*
1178: * Received authentication protocol and data match
1179: * our fake data. Substitute the fake data with real
1180: * data.
1181: */
1182: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1183: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1184: return 1;
1185: }
1186:
1.127 itojun 1187: static void
1.367 djm 1188: channel_pre_x11_open(struct ssh *ssh, Channel *c,
1189: fd_set *readset, fd_set *writeset)
1.41 markus 1190: {
1.367 djm 1191: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1192:
1193: /* c->force_drain = 1; */
1194:
1.41 markus 1195: if (ret == 1) {
1196: c->type = SSH_CHANNEL_OPEN;
1.367 djm 1197: channel_pre_open(ssh, c, readset, writeset);
1.41 markus 1198: } else if (ret == -1) {
1.188 itojun 1199: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1200: debug2("X11 rejected %d i%d/o%d",
1201: c->self, c->istate, c->ostate);
1202: chan_read_failed(ssh, c);
1203: sshbuf_reset(c->input);
1204: chan_ibuf_empty(ssh, c);
1205: sshbuf_reset(c->output);
1206: chan_write_failed(ssh, c);
1.194 markus 1207: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1208: }
1209: }
1.25 markus 1210:
1.302 djm 1211: static void
1.367 djm 1212: channel_pre_mux_client(struct ssh *ssh,
1213: Channel *c, fd_set *readset, fd_set *writeset)
1.302 djm 1214: {
1.304 djm 1215: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1216: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.302 djm 1217: FD_SET(c->rfd, readset);
1218: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1219: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1220: sshbuf_reset(c->input);
1221: chan_ibuf_empty(ssh, c);
1.302 djm 1222: /* Start output drain. XXX just kill chan? */
1.367 djm 1223: chan_rcvd_oclose(ssh, c);
1.302 djm 1224: }
1225: if (c->ostate == CHAN_OUTPUT_OPEN ||
1226: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1227: if (sshbuf_len(c->output) > 0)
1.302 djm 1228: FD_SET(c->wfd, writeset);
1229: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1230: chan_obuf_empty(ssh, c);
1.302 djm 1231: }
1232: }
1233:
1.104 markus 1234: /* try to decode a socks4 header */
1.127 itojun 1235: static int
1.372 markus 1236: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1237: {
1.367 djm 1238: const u_char *p;
1239: char *host;
1.292 djm 1240: u_int len, have, i, found, need;
1.148 deraadt 1241: char username[256];
1.103 markus 1242: struct {
1243: u_int8_t version;
1244: u_int8_t command;
1245: u_int16_t dest_port;
1.104 markus 1246: struct in_addr dest_addr;
1.103 markus 1247: } s4_req, s4_rsp;
1.367 djm 1248: int r;
1.103 markus 1249:
1.104 markus 1250: debug2("channel %d: decode socks4", c->self);
1.109 markus 1251:
1.372 markus 1252: have = sshbuf_len(input);
1.109 markus 1253: len = sizeof(s4_req);
1254: if (have < len)
1255: return 0;
1.372 markus 1256: p = sshbuf_ptr(input);
1.292 djm 1257:
1258: need = 1;
1259: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1260: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1261: debug2("channel %d: socks4a request", c->self);
1262: /* ... and needs an extra string (the hostname) */
1263: need = 2;
1264: }
1265: /* Check for terminating NUL on the string(s) */
1.109 markus 1266: for (found = 0, i = len; i < have; i++) {
1267: if (p[i] == '\0') {
1.292 djm 1268: found++;
1269: if (found == need)
1270: break;
1.109 markus 1271: }
1272: if (i > 1024) {
1273: /* the peer is probably sending garbage */
1274: debug("channel %d: decode socks4: too long",
1275: c->self);
1276: return -1;
1277: }
1278: }
1.292 djm 1279: if (found < need)
1.109 markus 1280: return 0;
1.372 markus 1281: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1282: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1283: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1284: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.367 djm 1285: debug("channels %d: decode socks4: %s", c->self, ssh_err(r));
1286: return -1;
1287: }
1.372 markus 1288: have = sshbuf_len(input);
1289: p = sshbuf_ptr(input);
1.364 djm 1290: if (memchr(p, '\0', have) == NULL) {
1291: error("channel %d: decode socks4: user not nul terminated",
1.331 djm 1292: c->self);
1.364 djm 1293: return -1;
1294: }
1.103 markus 1295: len = strlen(p);
1.106 markus 1296: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1297: len++; /* trailing '\0' */
1.103 markus 1298: strlcpy(username, p, sizeof(username));
1.372 markus 1299: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1300: fatal("%s: channel %d: consume: %s", __func__,
1301: c->self, ssh_err(r));
1302: }
1.321 djm 1303: free(c->path);
1304: c->path = NULL;
1.292 djm 1305: if (need == 1) { /* SOCKS4: one string */
1306: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1307: c->path = xstrdup(host);
1.292 djm 1308: } else { /* SOCKS4A: two strings */
1.372 markus 1309: have = sshbuf_len(input);
1310: p = sshbuf_ptr(input);
1.364 djm 1311: if (memchr(p, '\0', have) == NULL) {
1312: error("channel %d: decode socks4a: host not nul "
1313: "terminated", c->self);
1314: return -1;
1315: }
1.292 djm 1316: len = strlen(p);
1317: debug2("channel %d: decode socks4a: host %s/%d",
1318: c->self, p, len);
1319: len++; /* trailing '\0' */
1.293 djm 1320: if (len > NI_MAXHOST) {
1.292 djm 1321: error("channel %d: hostname \"%.100s\" too long",
1322: c->self, p);
1323: return -1;
1324: }
1.293 djm 1325: c->path = xstrdup(p);
1.372 markus 1326: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1327: fatal("%s: channel %d: consume: %s", __func__,
1328: c->self, ssh_err(r));
1329: }
1.292 djm 1330: }
1.103 markus 1331: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1332:
1.194 markus 1333: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1334: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1335:
1.104 markus 1336: if (s4_req.command != 1) {
1.292 djm 1337: debug("channel %d: cannot handle: %s cn %d",
1338: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1339: return -1;
1.103 markus 1340: }
1.104 markus 1341: s4_rsp.version = 0; /* vn: 0 for reply */
1342: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1343: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1344: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.372 markus 1345: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0) {
1.367 djm 1346: fatal("%s: channel %d: append reply: %s", __func__,
1347: c->self, ssh_err(r));
1348: }
1.104 markus 1349: return 1;
1350: }
1351:
1.193 markus 1352: /* try to decode a socks5 header */
1353: #define SSH_SOCKS5_AUTHDONE 0x1000
1354: #define SSH_SOCKS5_NOAUTH 0x00
1355: #define SSH_SOCKS5_IPV4 0x01
1356: #define SSH_SOCKS5_DOMAIN 0x03
1357: #define SSH_SOCKS5_IPV6 0x04
1358: #define SSH_SOCKS5_CONNECT 0x01
1359: #define SSH_SOCKS5_SUCCESS 0x00
1360:
1361: static int
1.372 markus 1362: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1363: {
1.367 djm 1364: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1365: struct {
1366: u_int8_t version;
1367: u_int8_t command;
1368: u_int8_t reserved;
1369: u_int8_t atyp;
1370: } s5_req, s5_rsp;
1371: u_int16_t dest_port;
1.324 djm 1372: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1373: const u_char *p;
1.252 djm 1374: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1375: int r;
1.193 markus 1376:
1377: debug2("channel %d: decode socks5", c->self);
1.372 markus 1378: p = sshbuf_ptr(input);
1.193 markus 1379: if (p[0] != 0x05)
1380: return -1;
1.372 markus 1381: have = sshbuf_len(input);
1.193 markus 1382: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1383: /* format: ver | nmethods | methods */
1.198 djm 1384: if (have < 2)
1.193 markus 1385: return 0;
1386: nmethods = p[1];
1387: if (have < nmethods + 2)
1388: return 0;
1389: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1390: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1391: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1392: found = 1;
1393: break;
1394: }
1395: }
1396: if (!found) {
1397: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1398: c->self);
1399: return -1;
1400: }
1.372 markus 1401: if ((r = sshbuf_consume(input, nmethods + 2)) != 0) {
1.367 djm 1402: fatal("%s: channel %d: consume: %s", __func__,
1403: c->self, ssh_err(r));
1404: }
1405: /* version, method */
1.372 markus 1406: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1407: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0) {
1.367 djm 1408: fatal("%s: channel %d: append reply: %s", __func__,
1409: c->self, ssh_err(r));
1410: }
1.193 markus 1411: c->flags |= SSH_SOCKS5_AUTHDONE;
1412: debug2("channel %d: socks5 auth done", c->self);
1413: return 0; /* need more */
1414: }
1415: debug2("channel %d: socks5 post auth", c->self);
1416: if (have < sizeof(s5_req)+1)
1417: return 0; /* need more */
1.247 deraadt 1418: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1419: if (s5_req.version != 0x05 ||
1420: s5_req.command != SSH_SOCKS5_CONNECT ||
1421: s5_req.reserved != 0x00) {
1.194 markus 1422: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1423: return -1;
1424: }
1.213 deraadt 1425: switch (s5_req.atyp){
1.193 markus 1426: case SSH_SOCKS5_IPV4:
1427: addrlen = 4;
1428: af = AF_INET;
1429: break;
1430: case SSH_SOCKS5_DOMAIN:
1431: addrlen = p[sizeof(s5_req)];
1432: af = -1;
1433: break;
1434: case SSH_SOCKS5_IPV6:
1435: addrlen = 16;
1436: af = AF_INET6;
1437: break;
1438: default:
1.194 markus 1439: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1440: return -1;
1441: }
1.252 djm 1442: need = sizeof(s5_req) + addrlen + 2;
1443: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1444: need++;
1445: if (have < need)
1.193 markus 1446: return 0;
1.372 markus 1447: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0) {
1.367 djm 1448: fatal("%s: channel %d: consume: %s", __func__,
1449: c->self, ssh_err(r));
1450: }
1451: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1452: /* host string length */
1.372 markus 1453: if ((r = sshbuf_consume(input, 1)) != 0) {
1.367 djm 1454: fatal("%s: channel %d: consume: %s", __func__,
1455: c->self, ssh_err(r));
1456: }
1457: }
1.372 markus 1458: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1459: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.367 djm 1460: debug("channel %d: parse addr/port: %s", c->self, ssh_err(r));
1461: return -1;
1462: }
1.193 markus 1463: dest_addr[addrlen] = '\0';
1.321 djm 1464: free(c->path);
1465: c->path = NULL;
1.293 djm 1466: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1467: if (addrlen >= NI_MAXHOST) {
1.293 djm 1468: error("channel %d: dynamic request: socks5 hostname "
1469: "\"%.100s\" too long", c->self, dest_addr);
1470: return -1;
1471: }
1472: c->path = xstrdup(dest_addr);
1473: } else {
1474: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1475: return -1;
1476: c->path = xstrdup(ntop);
1477: }
1.193 markus 1478: c->host_port = ntohs(dest_port);
1.198 djm 1479:
1.194 markus 1480: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1481: c->self, c->path, c->host_port, s5_req.command);
1482:
1483: s5_rsp.version = 0x05;
1484: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1485: s5_rsp.reserved = 0; /* ignored */
1486: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1487: dest_port = 0; /* ignored */
1488:
1.372 markus 1489: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1490: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1491: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.367 djm 1492: fatal("%s: channel %d: append reply: %s", __func__,
1493: c->self, ssh_err(r));
1.193 markus 1494: return 1;
1.301 dtucker 1495: }
1496:
1497: Channel *
1.367 djm 1498: channel_connect_stdio_fwd(struct ssh *ssh,
1499: const char *host_to_connect, u_short port_to_connect, int in, int out)
1.301 dtucker 1500: {
1501: Channel *c;
1502:
1.367 djm 1503: debug("%s %s:%d", __func__, host_to_connect, port_to_connect);
1.301 dtucker 1504:
1.367 djm 1505: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1506: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1507: 0, "stdio-forward", /*nonblock*/0);
1508:
1509: c->path = xstrdup(host_to_connect);
1510: c->host_port = port_to_connect;
1511: c->listening_port = 0;
1512: c->force_drain = 1;
1513:
1.367 djm 1514: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1515: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1516:
1517: return c;
1.193 markus 1518: }
1519:
1.104 markus 1520: /* dynamic port forwarding */
1.127 itojun 1521: static void
1.367 djm 1522: channel_pre_dynamic(struct ssh *ssh, Channel *c,
1523: fd_set *readset, fd_set *writeset)
1.104 markus 1524: {
1.367 djm 1525: const u_char *p;
1.217 djm 1526: u_int have;
1527: int ret;
1.103 markus 1528:
1.367 djm 1529: have = sshbuf_len(c->input);
1.104 markus 1530: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1531: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1532: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1533: if (have < 3) {
1.104 markus 1534: /* need more */
1535: FD_SET(c->sock, readset);
1536: return;
1537: }
1538: /* try to guess the protocol */
1.367 djm 1539: p = sshbuf_ptr(c->input);
1540: /* XXX sshbuf_peek_u8? */
1.104 markus 1541: switch (p[0]) {
1542: case 0x04:
1.372 markus 1543: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1544: break;
1545: case 0x05:
1.372 markus 1546: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1547: break;
1548: default:
1549: ret = -1;
1550: break;
1551: }
1552: if (ret < 0) {
1.367 djm 1553: chan_mark_dead(ssh, c);
1.104 markus 1554: } else if (ret == 0) {
1555: debug2("channel %d: pre_dynamic: need more", c->self);
1556: /* need more */
1557: FD_SET(c->sock, readset);
1.372 markus 1558: if (sshbuf_len(c->output))
1559: FD_SET(c->sock, writeset);
1.104 markus 1560: } else {
1561: /* switch to the next state */
1562: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1563: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1564: }
1.103 markus 1565: }
1566:
1.372 markus 1567: /* simulate read-error */
1568: static void
1569: rdynamic_close(struct ssh *ssh, Channel *c)
1570: {
1571: c->type = SSH_CHANNEL_OPEN;
1572: chan_read_failed(ssh, c);
1573: sshbuf_reset(c->input);
1574: chan_ibuf_empty(ssh, c);
1575: sshbuf_reset(c->output);
1576: chan_write_failed(ssh, c);
1577: }
1578:
1579: /* reverse dynamic port forwarding */
1580: static void
1581: channel_before_prepare_select_rdynamic(struct ssh *ssh, Channel *c)
1582: {
1583: const u_char *p;
1584: u_int have, len;
1585: int r, ret;
1586:
1587: have = sshbuf_len(c->output);
1588: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1589: /* sshbuf_dump(c->output, stderr); */
1590: /* EOF received */
1591: if (c->flags & CHAN_EOF_RCVD) {
1592: if ((r = sshbuf_consume(c->output, have)) != 0) {
1593: fatal("%s: channel %d: consume: %s",
1594: __func__, c->self, ssh_err(r));
1595: }
1596: rdynamic_close(ssh, c);
1597: return;
1598: }
1599: /* check if the fixed size part of the packet is in buffer. */
1600: if (have < 3)
1601: return;
1602: /* try to guess the protocol */
1603: p = sshbuf_ptr(c->output);
1604: switch (p[0]) {
1605: case 0x04:
1606: /* switch input/output for reverse forwarding */
1607: ret = channel_decode_socks4(c, c->output, c->input);
1608: break;
1609: case 0x05:
1610: ret = channel_decode_socks5(c, c->output, c->input);
1611: break;
1612: default:
1613: ret = -1;
1614: break;
1615: }
1616: if (ret < 0) {
1617: rdynamic_close(ssh, c);
1618: } else if (ret == 0) {
1619: debug2("channel %d: pre_rdynamic: need more", c->self);
1620: /* send socks request to peer */
1621: len = sshbuf_len(c->input);
1622: if (len > 0 && len < c->remote_window) {
1623: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1624: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1625: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1626: (r = sshpkt_send(ssh)) != 0) {
1627: fatal("%s: channel %i: rdynamic: %s", __func__,
1628: c->self, ssh_err(r));
1629: }
1630: if ((r = sshbuf_consume(c->input, len)) != 0) {
1631: fatal("%s: channel %d: consume: %s",
1632: __func__, c->self, ssh_err(r));
1633: }
1634: c->remote_window -= len;
1635: }
1636: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1637: /* the connect failed */
1638: rdynamic_close(ssh, c);
1639: }
1640: }
1641:
1.41 markus 1642: /* This is our fake X11 server socket. */
1.127 itojun 1643: static void
1.367 djm 1644: channel_post_x11_listener(struct ssh *ssh, Channel *c,
1645: fd_set *readset, fd_set *writeset)
1.41 markus 1646: {
1.113 markus 1647: Channel *nc;
1.285 djm 1648: struct sockaddr_storage addr;
1.367 djm 1649: int r, newsock, oerrno, remote_port;
1.41 markus 1650: socklen_t addrlen;
1.85 markus 1651: char buf[16384], *remote_ipaddr;
1.25 markus 1652:
1.367 djm 1653: if (!FD_ISSET(c->sock, readset))
1654: return;
1655:
1656: debug("X11 connection requested.");
1657: addrlen = sizeof(addr);
1658: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1659: if (c->single_connection) {
1660: oerrno = errno;
1661: debug2("single_connection: closing X11 listener.");
1662: channel_close_fd(ssh, &c->sock);
1663: chan_mark_dead(ssh, c);
1664: errno = oerrno;
1665: }
1.393 deraadt 1666: if (newsock == -1) {
1.367 djm 1667: if (errno != EINTR && errno != EWOULDBLOCK &&
1668: errno != ECONNABORTED)
1669: error("accept: %.100s", strerror(errno));
1670: if (errno == EMFILE || errno == ENFILE)
1671: c->notbefore = monotime() + 1;
1672: return;
1673: }
1674: set_nodelay(newsock);
1675: remote_ipaddr = get_peer_ipaddr(newsock);
1676: remote_port = get_peer_port(newsock);
1677: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1678: remote_ipaddr, remote_port);
1679:
1680: nc = channel_new(ssh, "accepted x11 socket",
1681: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1682: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1683: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1684: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1685: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.367 djm 1686: fatal("%s: channel %i: reply %s", __func__,
1687: c->self, ssh_err(r));
1.41 markus 1688: }
1.367 djm 1689: if ((r = sshpkt_send(ssh)) != 0)
1690: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1691: free(remote_ipaddr);
1.41 markus 1692: }
1.25 markus 1693:
1.127 itojun 1694: static void
1.367 djm 1695: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1696: {
1.328 djm 1697: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1698: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1699: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1700: int remote_port = get_peer_port(c->sock);
1.367 djm 1701: int r;
1.303 djm 1702:
1703: if (remote_port == -1) {
1704: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1705: free(remote_ipaddr);
1.303 djm 1706: remote_ipaddr = xstrdup("127.0.0.1");
1707: remote_port = 65535;
1708: }
1.103 markus 1709:
1.367 djm 1710: free(c->remote_name);
1711: xasprintf(&c->remote_name,
1.103 markus 1712: "%s: listening port %d for %.100s port %d, "
1.328 djm 1713: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1714: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1715: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1716:
1.367 djm 1717: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1718: if (strcmp(rtype, "direct-tcpip") == 0) {
1719: /* target host, port */
1.367 djm 1720: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1721: (r = sshpkt_put_u32(ssh, c->host_port)) != 0) {
1722: fatal("%s: channel %i: reply %s", __func__,
1723: c->self, ssh_err(r));
1724: }
1.358 djm 1725: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1726: /* target path */
1.367 djm 1727: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1728: fatal("%s: channel %i: reply %s", __func__,
1729: c->self, ssh_err(r));
1730: }
1.358 djm 1731: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1732: /* listen path */
1.367 djm 1733: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1734: fatal("%s: channel %i: reply %s", __func__,
1735: c->self, ssh_err(r));
1736: }
1.103 markus 1737: } else {
1.358 djm 1738: /* listen address, port */
1.367 djm 1739: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1740: (r = sshpkt_put_u32(ssh, local_port)) != 0) {
1741: fatal("%s: channel %i: reply %s", __func__,
1742: c->self, ssh_err(r));
1743: }
1.358 djm 1744: }
1745: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1746: /* reserved for future owner/mode info */
1.367 djm 1747: if ((r = sshpkt_put_cstring(ssh, "")) != 0) {
1748: fatal("%s: channel %i: reply %s", __func__,
1749: c->self, ssh_err(r));
1750: }
1.358 djm 1751: } else {
1752: /* originator host and port */
1.367 djm 1753: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1754: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0) {
1755: fatal("%s: channel %i: reply %s", __func__,
1756: c->self, ssh_err(r));
1757: }
1.103 markus 1758: }
1.367 djm 1759: if ((r = sshpkt_send(ssh)) != 0)
1760: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1.321 djm 1761: free(remote_ipaddr);
1.328 djm 1762: free(local_ipaddr);
1.103 markus 1763: }
1764:
1.347 djm 1765: void
1.367 djm 1766: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1767: {
1.367 djm 1768: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1769: }
1770:
1.41 markus 1771: /*
1772: * This socket is listening for connections to a forwarded TCP/IP port.
1773: */
1.127 itojun 1774: static void
1.367 djm 1775: channel_post_port_listener(struct ssh *ssh, Channel *c,
1776: fd_set *readset, fd_set *writeset)
1.41 markus 1777: {
1.103 markus 1778: Channel *nc;
1.285 djm 1779: struct sockaddr_storage addr;
1.113 markus 1780: int newsock, nextstate;
1.41 markus 1781: socklen_t addrlen;
1.103 markus 1782: char *rtype;
1.73 markus 1783:
1.367 djm 1784: if (!FD_ISSET(c->sock, readset))
1785: return;
1786:
1787: debug("Connection to port %d forwarding to %.100s port %d requested.",
1788: c->listening_port, c->path, c->host_port);
1.103 markus 1789:
1.367 djm 1790: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1791: nextstate = SSH_CHANNEL_OPENING;
1792: rtype = "forwarded-tcpip";
1793: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1794: nextstate = SSH_CHANNEL_OPENING;
1795: rtype = "forwarded-streamlocal@openssh.com";
1796: } else if (c->host_port == PORT_STREAMLOCAL) {
1797: nextstate = SSH_CHANNEL_OPENING;
1798: rtype = "direct-streamlocal@openssh.com";
1799: } else if (c->host_port == 0) {
1800: nextstate = SSH_CHANNEL_DYNAMIC;
1801: rtype = "dynamic-tcpip";
1802: } else {
1803: nextstate = SSH_CHANNEL_OPENING;
1804: rtype = "direct-tcpip";
1805: }
1.103 markus 1806:
1.367 djm 1807: addrlen = sizeof(addr);
1808: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1809: if (newsock == -1) {
1.367 djm 1810: if (errno != EINTR && errno != EWOULDBLOCK &&
1811: errno != ECONNABORTED)
1812: error("accept: %.100s", strerror(errno));
1813: if (errno == EMFILE || errno == ENFILE)
1814: c->notbefore = monotime() + 1;
1815: return;
1.41 markus 1816: }
1.367 djm 1817: if (c->host_port != PORT_STREAMLOCAL)
1818: set_nodelay(newsock);
1819: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1820: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1821: nc->listening_port = c->listening_port;
1822: nc->host_port = c->host_port;
1823: if (c->path != NULL)
1824: nc->path = xstrdup(c->path);
1825:
1826: if (nextstate != SSH_CHANNEL_DYNAMIC)
1827: port_open_helper(ssh, nc, rtype);
1.41 markus 1828: }
1.25 markus 1829:
1.41 markus 1830: /*
1831: * This is the authentication agent socket listening for connections from
1832: * clients.
1833: */
1.127 itojun 1834: static void
1.367 djm 1835: channel_post_auth_listener(struct ssh *ssh, Channel *c,
1836: fd_set *readset, fd_set *writeset)
1.41 markus 1837: {
1.113 markus 1838: Channel *nc;
1.367 djm 1839: int r, newsock;
1.285 djm 1840: struct sockaddr_storage addr;
1.41 markus 1841: socklen_t addrlen;
1.25 markus 1842:
1.367 djm 1843: if (!FD_ISSET(c->sock, readset))
1844: return;
1845:
1846: addrlen = sizeof(addr);
1847: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1848: if (newsock == -1) {
1.367 djm 1849: error("accept from auth socket: %.100s", strerror(errno));
1850: if (errno == EMFILE || errno == ENFILE)
1851: c->notbefore = monotime() + 1;
1852: return;
1.41 markus 1853: }
1.367 djm 1854: nc = channel_new(ssh, "accepted auth socket",
1855: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1856: c->local_window_max, c->local_maxpacket,
1857: 0, "accepted auth socket", 1);
1858: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1859: if ((r = sshpkt_send(ssh)) != 0)
1860: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.41 markus 1861: }
1.25 markus 1862:
1.127 itojun 1863: static void
1.367 djm 1864: channel_post_connecting(struct ssh *ssh, Channel *c,
1865: fd_set *readset, fd_set *writeset)
1.75 markus 1866: {
1.372 markus 1867: int err = 0, sock, isopen, r;
1.129 stevesk 1868: socklen_t sz = sizeof(err);
1.114 markus 1869:
1.367 djm 1870: if (!FD_ISSET(c->sock, writeset))
1871: return;
1.368 djm 1872: if (!c->have_remote_id)
1873: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.372 markus 1874: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1875: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.393 deraadt 1876: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 1877: err = errno;
1878: error("getsockopt SO_ERROR failed");
1879: }
1880: if (err == 0) {
1881: debug("channel %d: connected to %s port %d",
1882: c->self, c->connect_ctx.host, c->connect_ctx.port);
1883: channel_connect_ctx_free(&c->connect_ctx);
1884: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1885: if (isopen) {
1886: /* no message necessary */
1887: } else {
1888: if ((r = sshpkt_start(ssh,
1889: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1890: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1891: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1892: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1893: (r = sshpkt_put_u32(ssh, c->local_maxpacket))
1894: != 0)
1895: fatal("%s: channel %i: confirm: %s", __func__,
1896: c->self, ssh_err(r));
1897: if ((r = sshpkt_send(ssh)) != 0)
1898: fatal("%s: channel %i: %s", __func__, c->self,
1899: ssh_err(r));
1.367 djm 1900: }
1901: } else {
1902: debug("channel %d: connection failed: %s",
1903: c->self, strerror(err));
1904: /* Try next address, if any */
1905: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1906: close(c->sock);
1907: c->sock = c->rfd = c->wfd = sock;
1908: channel_find_maxfd(ssh->chanctxt);
1909: return;
1910: }
1911: /* Exhausted all addresses */
1912: error("connect_to %.100s port %d: failed.",
1913: c->connect_ctx.host, c->connect_ctx.port);
1914: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1915: if (isopen) {
1916: rdynamic_close(ssh, c);
1917: } else {
1918: if ((r = sshpkt_start(ssh,
1919: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1920: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 1921: (r = sshpkt_put_u32(ssh,
1922: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
1923: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1924: (r = sshpkt_put_cstring(ssh, "")) != 0) {
1.372 markus 1925: fatal("%s: channel %i: failure: %s", __func__,
1926: c->self, ssh_err(r));
1.378 djm 1927: }
1.372 markus 1928: if ((r = sshpkt_send(ssh)) != 0)
1929: fatal("%s: channel %i: %s", __func__, c->self,
1930: ssh_err(r));
1931: chan_mark_dead(ssh, c);
1.75 markus 1932: }
1933: }
1934: }
1935:
1.127 itojun 1936: static int
1.367 djm 1937: channel_handle_rfd(struct ssh *ssh, Channel *c,
1938: fd_set *readset, fd_set *writeset)
1.41 markus 1939: {
1.214 markus 1940: char buf[CHAN_RBUF];
1.367 djm 1941: ssize_t len;
1942: int r;
1.25 markus 1943:
1.367 djm 1944: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
1945: return 1;
1946:
1947: len = read(c->rfd, buf, sizeof(buf));
1.393 deraadt 1948: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 1949: return 1;
1950: if (len <= 0) {
1951: debug2("channel %d: read<=0 rfd %d len %zd",
1952: c->self, c->rfd, len);
1953: if (c->type != SSH_CHANNEL_OPEN) {
1954: debug2("channel %d: not open", c->self);
1955: chan_mark_dead(ssh, c);
1.41 markus 1956: return -1;
1.65 markus 1957: } else {
1.367 djm 1958: chan_read_failed(ssh, c);
1.65 markus 1959: }
1.367 djm 1960: return -1;
1961: }
1962: if (c->input_filter != NULL) {
1963: if (c->input_filter(ssh, c, buf, len) == -1) {
1964: debug2("channel %d: filter stops", c->self);
1965: chan_read_failed(ssh, c);
1966: }
1967: } else if (c->datagram) {
1968: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1969: fatal("%s: channel %d: put datagram: %s", __func__,
1970: c->self, ssh_err(r));
1971: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
1972: fatal("%s: channel %d: put data: %s", __func__,
1973: c->self, ssh_err(r));
1.41 markus 1974: }
1975: return 1;
1976: }
1.241 deraadt 1977:
1.127 itojun 1978: static int
1.367 djm 1979: channel_handle_wfd(struct ssh *ssh, Channel *c,
1980: fd_set *readset, fd_set *writeset)
1.41 markus 1981: {
1.95 markus 1982: struct termios tio;
1.367 djm 1983: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1984: size_t dlen, olen = 0;
1985: int r, len;
1986:
1987: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
1988: sshbuf_len(c->output) == 0)
1989: return 1;
1.25 markus 1990:
1.41 markus 1991: /* Send buffered output data to the socket. */
1.367 djm 1992: olen = sshbuf_len(c->output);
1993: if (c->output_filter != NULL) {
1994: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1995: debug2("channel %d: filter stops", c->self);
1996: if (c->type != SSH_CHANNEL_OPEN)
1997: chan_mark_dead(ssh, c);
1998: else
1999: chan_write_failed(ssh, c);
2000: return -1;
1.231 reyk 2001: }
1.367 djm 2002: } else if (c->datagram) {
2003: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
2004: fatal("%s: channel %d: get datagram: %s", __func__,
2005: c->self, ssh_err(r));
1.369 djm 2006: buf = data;
1.367 djm 2007: } else {
2008: buf = data = sshbuf_mutable_ptr(c->output);
2009: dlen = sshbuf_len(c->output);
2010: }
1.231 reyk 2011:
1.367 djm 2012: if (c->datagram) {
2013: /* ignore truncated writes, datagrams might get lost */
1.374 djm 2014: len = write(c->wfd, buf, dlen);
1.367 djm 2015: free(data);
1.393 deraadt 2016: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 2017: return 1;
1.367 djm 2018: if (len <= 0)
2019: goto write_fail;
2020: goto out;
2021: }
2022:
2023: len = write(c->wfd, buf, dlen);
1.393 deraadt 2024: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2025: return 1;
2026: if (len <= 0) {
2027: write_fail:
2028: if (c->type != SSH_CHANNEL_OPEN) {
2029: debug2("channel %d: not open", c->self);
2030: chan_mark_dead(ssh, c);
1.41 markus 2031: return -1;
1.367 djm 2032: } else {
2033: chan_write_failed(ssh, c);
1.91 markus 2034: }
1.367 djm 2035: return -1;
2036: }
2037: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2038: if (tcgetattr(c->wfd, &tio) == 0 &&
2039: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2040: /*
2041: * Simulate echo to reduce the impact of
2042: * traffic analysis. We need to match the
2043: * size of a SSH2_MSG_CHANNEL_DATA message
2044: * (4 byte channel id + buf)
2045: */
2046: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2047: (r = sshpkt_send(ssh)) != 0)
2048: fatal("%s: channel %d: ignore: %s",
2049: __func__, c->self, ssh_err(r));
1.25 markus 2050: }
1.367 djm 2051: }
2052: if ((r = sshbuf_consume(c->output, len)) != 0) {
2053: fatal("%s: channel %d: consume: %s",
2054: __func__, c->self, ssh_err(r));
1.44 markus 2055: }
1.309 djm 2056: out:
1.367 djm 2057: c->local_consumed += olen - sshbuf_len(c->output);
2058:
2059: return 1;
2060: }
2061:
2062: static int
2063: channel_handle_efd_write(struct ssh *ssh, Channel *c,
2064: fd_set *readset, fd_set *writeset)
2065: {
2066: int r;
2067: ssize_t len;
2068:
2069: if (!FD_ISSET(c->efd, writeset) || sshbuf_len(c->extended) == 0)
2070: return 1;
2071:
2072: len = write(c->efd, sshbuf_ptr(c->extended),
2073: sshbuf_len(c->extended));
2074: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 deraadt 2075: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2076: return 1;
2077: if (len <= 0) {
2078: debug2("channel %d: closing write-efd %d", c->self, c->efd);
2079: channel_close_fd(ssh, &c->efd);
2080: } else {
2081: if ((r = sshbuf_consume(c->extended, len)) != 0) {
2082: fatal("%s: channel %d: consume: %s",
2083: __func__, c->self, ssh_err(r));
2084: }
2085: c->local_consumed += len;
2086: }
1.44 markus 2087: return 1;
2088: }
1.241 deraadt 2089:
1.127 itojun 2090: static int
1.367 djm 2091: channel_handle_efd_read(struct ssh *ssh, Channel *c,
2092: fd_set *readset, fd_set *writeset)
1.44 markus 2093: {
1.214 markus 2094: char buf[CHAN_RBUF];
1.367 djm 2095: int r;
2096: ssize_t len;
2097:
2098: if (!FD_ISSET(c->efd, readset))
2099: return 1;
1.44 markus 2100:
1.367 djm 2101: len = read(c->efd, buf, sizeof(buf));
2102: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 deraadt 2103: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2104: return 1;
2105: if (len <= 0) {
2106: debug2("channel %d: closing read-efd %d",
2107: c->self, c->efd);
2108: channel_close_fd(ssh, &c->efd);
2109: } else {
2110: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
2111: debug3("channel %d: discard efd",
2112: c->self);
2113: } else if ((r = sshbuf_put(c->extended, buf, len)) != 0) {
2114: fatal("%s: channel %d: append: %s",
2115: __func__, c->self, ssh_err(r));
1.44 markus 2116: }
2117: }
2118: return 1;
2119: }
1.241 deraadt 2120:
1.127 itojun 2121: static int
1.367 djm 2122: channel_handle_efd(struct ssh *ssh, Channel *c,
2123: fd_set *readset, fd_set *writeset)
1.44 markus 2124: {
1.367 djm 2125: if (c->efd == -1)
2126: return 1;
2127:
2128: /** XXX handle drain efd, too */
2129:
2130: if (c->extended_usage == CHAN_EXTENDED_WRITE)
2131: return channel_handle_efd_write(ssh, c, readset, writeset);
2132: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2133: c->extended_usage == CHAN_EXTENDED_IGNORE)
2134: return channel_handle_efd_read(ssh, c, readset, writeset);
2135:
2136: return 1;
2137: }
2138:
2139: static int
2140: channel_check_window(struct ssh *ssh, Channel *c)
2141: {
2142: int r;
2143:
1.104 markus 2144: if (c->type == SSH_CHANNEL_OPEN &&
2145: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2146: ((c->local_window_max - c->local_window >
1.269 markus 2147: c->local_maxpacket*3) ||
2148: c->local_window < c->local_window_max/2) &&
1.44 markus 2149: c->local_consumed > 0) {
1.368 djm 2150: if (!c->have_remote_id)
2151: fatal(":%s: channel %d: no remote id",
2152: __func__, c->self);
1.367 djm 2153: if ((r = sshpkt_start(ssh,
2154: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2155: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2156: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2157: (r = sshpkt_send(ssh)) != 0) {
2158: fatal("%s: channel %i: %s", __func__,
2159: c->self, ssh_err(r));
2160: }
1.70 markus 2161: debug2("channel %d: window %d sent adjust %d",
1.44 markus 2162: c->self, c->local_window,
2163: c->local_consumed);
2164: c->local_window += c->local_consumed;
2165: c->local_consumed = 0;
1.1 deraadt 2166: }
1.41 markus 2167: return 1;
1.1 deraadt 2168: }
2169:
1.127 itojun 2170: static void
1.367 djm 2171: channel_post_open(struct ssh *ssh, Channel *c,
2172: fd_set *readset, fd_set *writeset)
1.41 markus 2173: {
1.367 djm 2174: channel_handle_rfd(ssh, c, readset, writeset);
2175: channel_handle_wfd(ssh, c, readset, writeset);
2176: channel_handle_efd(ssh, c, readset, writeset);
2177: channel_check_window(ssh, c);
1.44 markus 2178: }
2179:
1.302 djm 2180: static u_int
1.367 djm 2181: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2182: {
2183: char buf[CHAN_RBUF];
1.367 djm 2184: ssize_t len;
1.302 djm 2185: u_int rlen;
1.367 djm 2186: int r;
1.302 djm 2187:
1.367 djm 2188: if (sshbuf_len(c->input) < need) {
2189: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2190: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 deraadt 2191: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2192: return sshbuf_len(c->input);
1.302 djm 2193: if (len <= 0) {
1.367 djm 2194: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2195: c->self, c->rfd, len);
1.367 djm 2196: chan_read_failed(ssh, c);
1.349 naddy 2197: return 0;
1.367 djm 2198: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
2199: fatal("%s: channel %d: append: %s",
2200: __func__, c->self, ssh_err(r));
2201: }
1.302 djm 2202: }
1.367 djm 2203: return sshbuf_len(c->input);
1.302 djm 2204: }
2205:
2206: static void
1.367 djm 2207: channel_post_mux_client_read(struct ssh *ssh, Channel *c,
2208: fd_set *readset, fd_set *writeset)
1.302 djm 2209: {
2210: u_int need;
2211:
1.367 djm 2212: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
2213: return;
2214: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2215: return;
2216: if (c->mux_pause)
2217: return;
2218:
2219: /*
2220: * Don't not read past the precise end of packets to
2221: * avoid disrupting fd passing.
2222: */
2223: if (read_mux(ssh, c, 4) < 4) /* read header */
2224: return;
2225: /* XXX sshbuf_peek_u32 */
2226: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2227: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2228: if (need > CHANNEL_MUX_MAX_PACKET) {
2229: debug2("channel %d: packet too big %u > %u",
2230: c->self, CHANNEL_MUX_MAX_PACKET, need);
2231: chan_rcvd_oclose(ssh, c);
2232: return;
2233: }
2234: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2235: return;
2236: if (c->mux_rcb(ssh, c) != 0) {
2237: debug("channel %d: mux_rcb failed", c->self);
2238: chan_mark_dead(ssh, c);
2239: return;
1.302 djm 2240: }
1.367 djm 2241: }
2242:
2243: static void
2244: channel_post_mux_client_write(struct ssh *ssh, Channel *c,
2245: fd_set *readset, fd_set *writeset)
2246: {
2247: ssize_t len;
2248: int r;
1.302 djm 2249:
1.367 djm 2250: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
2251: sshbuf_len(c->output) == 0)
2252: return;
2253:
2254: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 deraadt 2255: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2256: return;
2257: if (len <= 0) {
2258: chan_mark_dead(ssh, c);
2259: return;
1.302 djm 2260: }
1.367 djm 2261: if ((r = sshbuf_consume(c->output, len)) != 0)
2262: fatal("%s: channel %d: consume: %s", __func__,
2263: c->self, ssh_err(r));
2264: }
2265:
2266: static void
2267: channel_post_mux_client(struct ssh *ssh, Channel *c,
2268: fd_set *readset, fd_set *writeset)
2269: {
2270: channel_post_mux_client_read(ssh, c, readset, writeset);
2271: channel_post_mux_client_write(ssh, c, readset, writeset);
1.302 djm 2272: }
2273:
2274: static void
1.367 djm 2275: channel_post_mux_listener(struct ssh *ssh, Channel *c,
2276: fd_set *readset, fd_set *writeset)
1.302 djm 2277: {
2278: Channel *nc;
2279: struct sockaddr_storage addr;
2280: socklen_t addrlen;
2281: int newsock;
2282: uid_t euid;
2283: gid_t egid;
2284:
2285: if (!FD_ISSET(c->sock, readset))
2286: return;
2287:
2288: debug("multiplexing control connection");
2289:
2290: /*
2291: * Accept connection on control socket
2292: */
2293: memset(&addr, 0, sizeof(addr));
2294: addrlen = sizeof(addr);
2295: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2296: &addrlen)) == -1) {
2297: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 2298: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2299: c->notbefore = monotime() + 1;
1.302 djm 2300: return;
2301: }
2302:
1.393 deraadt 2303: if (getpeereid(newsock, &euid, &egid) == -1) {
1.302 djm 2304: error("%s getpeereid failed: %s", __func__,
2305: strerror(errno));
2306: close(newsock);
2307: return;
2308: }
2309: if ((euid != 0) && (getuid() != euid)) {
2310: error("multiplex uid mismatch: peer euid %u != uid %u",
2311: (u_int)euid, (u_int)getuid());
2312: close(newsock);
2313: return;
2314: }
1.367 djm 2315: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2316: newsock, newsock, -1, c->local_window_max,
2317: c->local_maxpacket, 0, "mux-control", 1);
2318: nc->mux_rcb = c->mux_rcb;
1.367 djm 2319: debug3("%s: new mux channel %d fd %d", __func__, nc->self, nc->sock);
1.302 djm 2320: /* establish state */
1.367 djm 2321: nc->mux_rcb(ssh, nc);
1.302 djm 2322: /* mux state transitions must not elicit protocol messages */
2323: nc->flags |= CHAN_LOCAL;
2324: }
2325:
1.127 itojun 2326: static void
1.367 djm 2327: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2328: {
1.367 djm 2329: chan_fn **pre, **post;
2330:
2331: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
2332: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
2333: fatal("%s: allocation failed", __func__);
2334:
2335: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2336: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2337: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2338: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2339: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2340: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2341: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2342: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2343: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2344: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2345: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2346: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2347: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2348:
2349: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2350: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2351: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2352: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2353: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2354: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2355: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2356: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2357: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2358: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2359: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2360: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2361:
1.367 djm 2362: sc->channel_pre = pre;
2363: sc->channel_post = post;
1.44 markus 2364: }
2365:
1.140 markus 2366: /* gc dead channels */
2367: static void
1.367 djm 2368: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2369: {
2370: if (c == NULL)
2371: return;
2372: if (c->detach_user != NULL) {
1.367 djm 2373: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2374: return;
1.385 djm 2375:
1.194 markus 2376: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2377: c->detach_user(ssh, c->self, NULL);
1.140 markus 2378: /* if we still have a callback */
2379: if (c->detach_user != NULL)
2380: return;
1.194 markus 2381: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2382: }
1.367 djm 2383: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2384: return;
1.194 markus 2385: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2386: channel_free(ssh, c);
1.140 markus 2387: }
2388:
1.367 djm 2389: enum channel_table { CHAN_PRE, CHAN_POST };
2390:
1.127 itojun 2391: static void
1.367 djm 2392: channel_handler(struct ssh *ssh, int table,
1.366 djm 2393: fd_set *readset, fd_set *writeset, time_t *unpause_secs)
1.41 markus 2394: {
1.367 djm 2395: struct ssh_channels *sc = ssh->chanctxt;
2396: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2397: u_int i, oalloc;
1.41 markus 2398: Channel *c;
1.317 djm 2399: time_t now;
1.25 markus 2400:
1.322 dtucker 2401: now = monotime();
1.317 djm 2402: if (unpause_secs != NULL)
2403: *unpause_secs = 0;
1.367 djm 2404: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2405: c = sc->channels[i];
1.113 markus 2406: if (c == NULL)
1.41 markus 2407: continue;
1.299 markus 2408: if (c->delayed) {
1.367 djm 2409: if (table == CHAN_PRE)
1.299 markus 2410: c->delayed = 0;
2411: else
2412: continue;
2413: }
1.317 djm 2414: if (ftab[c->type] != NULL) {
2415: /*
2416: * Run handlers that are not paused.
2417: */
2418: if (c->notbefore <= now)
1.367 djm 2419: (*ftab[c->type])(ssh, c, readset, writeset);
1.317 djm 2420: else if (unpause_secs != NULL) {
2421: /*
2422: * Collect the time that the earliest
2423: * channel comes off pause.
2424: */
2425: debug3("%s: chan %d: skip for %d more seconds",
2426: __func__, c->self,
2427: (int)(c->notbefore - now));
2428: if (*unpause_secs == 0 ||
2429: (c->notbefore - now) < *unpause_secs)
2430: *unpause_secs = c->notbefore - now;
2431: }
2432: }
1.367 djm 2433: channel_garbage_collect(ssh, c);
1.1 deraadt 2434: }
1.317 djm 2435: if (unpause_secs != NULL && *unpause_secs != 0)
2436: debug3("%s: first channel unpauses in %d seconds",
2437: __func__, (int)*unpause_secs);
1.1 deraadt 2438: }
2439:
1.121 markus 2440: /*
1.372 markus 2441: * Create sockets before allocating the select bitmasks.
2442: * This is necessary for things that need to happen after reading
2443: * the network-input but before channel_prepare_select().
2444: */
2445: static void
2446: channel_before_prepare_select(struct ssh *ssh)
2447: {
2448: struct ssh_channels *sc = ssh->chanctxt;
2449: Channel *c;
2450: u_int i, oalloc;
2451:
2452: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2453: c = sc->channels[i];
2454: if (c == NULL)
2455: continue;
2456: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
2457: channel_before_prepare_select_rdynamic(ssh, c);
2458: }
2459: }
2460:
2461: /*
1.121 markus 2462: * Allocate/update select bitmasks and add any bits relevant to channels in
2463: * select bitmasks.
2464: */
1.49 markus 2465: void
1.366 djm 2466: channel_prepare_select(struct ssh *ssh, fd_set **readsetp, fd_set **writesetp,
2467: int *maxfdp, u_int *nallocp, time_t *minwait_secs)
1.41 markus 2468: {
1.243 djm 2469: u_int n, sz, nfdset;
1.84 markus 2470:
1.372 markus 2471: channel_before_prepare_select(ssh); /* might update channel_max_fd */
2472:
1.367 djm 2473: n = MAXIMUM(*maxfdp, ssh->chanctxt->channel_max_fd);
1.84 markus 2474:
1.243 djm 2475: nfdset = howmany(n+1, NFDBITS);
2476: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2477: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2478: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2479: sz = nfdset * sizeof(fd_mask);
2480:
1.132 markus 2481: /* perhaps check sz < nalloc/2 and shrink? */
2482: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2483: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2484: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2485: *nallocp = sz;
1.84 markus 2486: }
1.132 markus 2487: *maxfdp = n;
1.84 markus 2488: memset(*readsetp, 0, sz);
2489: memset(*writesetp, 0, sz);
2490:
1.366 djm 2491: if (!ssh_packet_is_rekeying(ssh))
1.367 djm 2492: channel_handler(ssh, CHAN_PRE, *readsetp, *writesetp,
1.317 djm 2493: minwait_secs);
1.41 markus 2494: }
2495:
1.121 markus 2496: /*
2497: * After select, perform any appropriate operations for channels which have
2498: * events pending.
2499: */
1.49 markus 2500: void
1.366 djm 2501: channel_after_select(struct ssh *ssh, fd_set *readset, fd_set *writeset)
1.41 markus 2502: {
1.367 djm 2503: channel_handler(ssh, CHAN_POST, readset, writeset, NULL);
2504: }
2505:
2506: /*
2507: * Enqueue data for channels with open or draining c->input.
2508: */
2509: static void
2510: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2511: {
1.373 djm 2512: size_t len, plen;
2513: const u_char *pkt;
1.367 djm 2514: int r;
2515:
2516: if ((len = sshbuf_len(c->input)) == 0) {
2517: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2518: /*
2519: * input-buffer is empty and read-socket shutdown:
2520: * tell peer, that we will not send more data:
2521: * send IEOF.
2522: * hack for extended data: delay EOF if EFD still
2523: * in use.
2524: */
2525: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2526: debug2("channel %d: "
2527: "ibuf_empty delayed efd %d/(%zu)",
2528: c->self, c->efd, sshbuf_len(c->extended));
2529: else
2530: chan_ibuf_empty(ssh, c);
2531: }
2532: return;
2533: }
2534:
1.368 djm 2535: if (!c->have_remote_id)
2536: fatal(":%s: channel %d: no remote id", __func__, c->self);
2537:
1.367 djm 2538: if (c->datagram) {
2539: /* Check datagram will fit; drop if not */
1.373 djm 2540: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
2541: fatal("%s: channel %d: get datagram: %s", __func__,
1.367 djm 2542: c->self, ssh_err(r));
2543: /*
2544: * XXX this does tail-drop on the datagram queue which is
2545: * usually suboptimal compared to head-drop. Better to have
2546: * backpressure at read time? (i.e. read + discard)
2547: */
1.373 djm 2548: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2549: debug("channel %d: datagram too big", c->self);
2550: return;
2551: }
2552: /* Enqueue it */
2553: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2554: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2555: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.367 djm 2556: (r = sshpkt_send(ssh)) != 0) {
2557: fatal("%s: channel %i: datagram: %s", __func__,
2558: c->self, ssh_err(r));
2559: }
1.373 djm 2560: c->remote_window -= plen;
1.367 djm 2561: return;
2562: }
2563:
2564: /* Enqueue packet for buffered data. */
2565: if (len > c->remote_window)
2566: len = c->remote_window;
2567: if (len > c->remote_maxpacket)
2568: len = c->remote_maxpacket;
2569: if (len == 0)
2570: return;
2571: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2572: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2573: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
2574: (r = sshpkt_send(ssh)) != 0) {
2575: fatal("%s: channel %i: data: %s", __func__,
2576: c->self, ssh_err(r));
2577: }
2578: if ((r = sshbuf_consume(c->input, len)) != 0)
2579: fatal("%s: channel %i: consume: %s", __func__,
2580: c->self, ssh_err(r));
2581: c->remote_window -= len;
1.41 markus 2582: }
2583:
1.367 djm 2584: /*
2585: * Enqueue data for channels with open c->extended in read mode.
2586: */
2587: static void
2588: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2589: {
2590: size_t len;
2591: int r;
2592:
2593: if ((len = sshbuf_len(c->extended)) == 0)
2594: return;
2595:
2596: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2597: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2598: if (len > c->remote_window)
2599: len = c->remote_window;
2600: if (len > c->remote_maxpacket)
2601: len = c->remote_maxpacket;
2602: if (len == 0)
2603: return;
1.368 djm 2604: if (!c->have_remote_id)
2605: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.367 djm 2606: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2607: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2608: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2609: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
2610: (r = sshpkt_send(ssh)) != 0) {
2611: fatal("%s: channel %i: data: %s", __func__,
2612: c->self, ssh_err(r));
2613: }
2614: if ((r = sshbuf_consume(c->extended, len)) != 0)
2615: fatal("%s: channel %i: consume: %s", __func__,
2616: c->self, ssh_err(r));
2617: c->remote_window -= len;
2618: debug2("channel %d: sent ext data %zu", c->self, len);
2619: }
1.121 markus 2620:
1.84 markus 2621: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2622: void
1.367 djm 2623: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2624: {
1.367 djm 2625: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2626: Channel *c;
1.367 djm 2627: u_int i;
1.1 deraadt 2628:
1.367 djm 2629: for (i = 0; i < sc->channels_alloc; i++) {
2630: c = sc->channels[i];
1.113 markus 2631: if (c == NULL)
2632: continue;
1.37 markus 2633:
1.121 markus 2634: /*
2635: * We are only interested in channels that can have buffered
2636: * incoming data.
2637: */
1.358 djm 2638: if (c->type != SSH_CHANNEL_OPEN)
2639: continue;
2640: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2641: /* XXX is this true? */
1.367 djm 2642: debug3("channel %d: will not send data after close",
2643: c->self);
1.44 markus 2644: continue;
2645: }
1.25 markus 2646:
2647: /* Get the amount of buffered data for this channel. */
1.367 djm 2648: if (c->istate == CHAN_INPUT_OPEN ||
2649: c->istate == CHAN_INPUT_WAIT_DRAIN)
2650: channel_output_poll_input_open(ssh, c);
1.44 markus 2651: /* Send extended data, i.e. stderr */
1.358 djm 2652: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2653: c->extended_usage == CHAN_EXTENDED_READ)
2654: channel_output_poll_extended_read(ssh, c);
1.25 markus 2655: }
1.1 deraadt 2656: }
2657:
1.354 markus 2658: /* -- mux proxy support */
2659:
2660: /*
2661: * When multiplexing channel messages for mux clients we have to deal
2662: * with downstream messages from the mux client and upstream messages
2663: * from the ssh server:
2664: * 1) Handling downstream messages is straightforward and happens
2665: * in channel_proxy_downstream():
2666: * - We forward all messages (mostly) unmodified to the server.
2667: * - However, in order to route messages from upstream to the correct
2668: * downstream client, we have to replace the channel IDs used by the
2669: * mux clients with a unique channel ID because the mux clients might
2670: * use conflicting channel IDs.
2671: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2672: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2673: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2674: * with the newly allocated channel ID.
2675: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 2676: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 2677: * is then translated back to the original mux client ID.
2678: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2679: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2680: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2681: * downstream mux client are removed.
2682: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2683: * requires more work, because they are not addressed to a specific
2684: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2685: * out whether the request is addressed to the local client or a
2686: * specific downstream client based on the listen-address/port.
1.380 djm 2687: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 2688: * not supported as the matching session/channel cannot be identified
2689: * easily.
2690: */
2691:
2692: /*
2693: * receive packets from downstream mux clients:
2694: * channel callback fired on read from mux client, creates
2695: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2696: * on channel creation.
2697: */
2698: int
1.367 djm 2699: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2700: {
2701: Channel *c = NULL;
2702: struct sshbuf *original = NULL, *modified = NULL;
2703: const u_char *cp;
2704: char *ctype = NULL, *listen_host = NULL;
2705: u_char type;
2706: size_t have;
1.370 djm 2707: int ret = -1, r;
1.355 djm 2708: u_int id, remote_id, listen_port;
1.354 markus 2709:
1.367 djm 2710: /* sshbuf_dump(downstream->input, stderr); */
2711: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2712: != 0) {
2713: error("%s: malformed message: %s", __func__, ssh_err(r));
2714: return -1;
2715: }
2716: if (have < 2) {
2717: error("%s: short message", __func__);
2718: return -1;
2719: }
2720: type = cp[1];
2721: /* skip padlen + type */
2722: cp += 2;
2723: have -= 2;
2724: if (ssh_packet_log_type(type))
2725: debug3("%s: channel %u: down->up: type %u", __func__,
2726: downstream->self, type);
2727:
2728: switch (type) {
2729: case SSH2_MSG_CHANNEL_OPEN:
2730: if ((original = sshbuf_from(cp, have)) == NULL ||
2731: (modified = sshbuf_new()) == NULL) {
2732: error("%s: alloc", __func__);
2733: goto out;
2734: }
2735: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2736: (r = sshbuf_get_u32(original, &id)) != 0) {
2737: error("%s: parse error %s", __func__, ssh_err(r));
2738: goto out;
2739: }
1.367 djm 2740: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2741: -1, -1, -1, 0, 0, 0, ctype, 1);
2742: c->mux_ctx = downstream; /* point to mux client */
2743: c->mux_downstream_id = id; /* original downstream id */
2744: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2745: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2746: (r = sshbuf_putb(modified, original)) != 0) {
2747: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2748: channel_free(ssh, c);
1.354 markus 2749: goto out;
2750: }
2751: break;
2752: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2753: /*
2754: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2755: * need to parse 'remote_id' instead of 'ctype'.
2756: */
2757: if ((original = sshbuf_from(cp, have)) == NULL ||
2758: (modified = sshbuf_new()) == NULL) {
2759: error("%s: alloc", __func__);
2760: goto out;
2761: }
2762: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2763: (r = sshbuf_get_u32(original, &id)) != 0) {
2764: error("%s: parse error %s", __func__, ssh_err(r));
2765: goto out;
2766: }
1.367 djm 2767: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2768: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
2769: c->mux_ctx = downstream; /* point to mux client */
2770: c->mux_downstream_id = id;
2771: c->remote_id = remote_id;
1.368 djm 2772: c->have_remote_id = 1;
1.354 markus 2773: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2774: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2775: (r = sshbuf_putb(modified, original)) != 0) {
2776: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2777: channel_free(ssh, c);
1.354 markus 2778: goto out;
2779: }
2780: break;
2781: case SSH2_MSG_GLOBAL_REQUEST:
2782: if ((original = sshbuf_from(cp, have)) == NULL) {
2783: error("%s: alloc", __func__);
2784: goto out;
2785: }
2786: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
2787: error("%s: parse error %s", __func__, ssh_err(r));
2788: goto out;
2789: }
2790: if (strcmp(ctype, "tcpip-forward") != 0) {
2791: error("%s: unsupported request %s", __func__, ctype);
2792: goto out;
2793: }
2794: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2795: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2796: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
2797: error("%s: parse error %s", __func__, ssh_err(r));
2798: goto out;
2799: }
1.355 djm 2800: if (listen_port > 65535) {
2801: error("%s: tcpip-forward for %s: bad port %u",
2802: __func__, listen_host, listen_port);
2803: goto out;
2804: }
1.354 markus 2805: /* Record that connection to this host/port is permitted. */
1.381 djm 2806: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 2807: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 2808: listen_host = NULL;
2809: break;
2810: case SSH2_MSG_CHANNEL_CLOSE:
2811: if (have < 4)
2812: break;
2813: remote_id = PEEK_U32(cp);
1.367 djm 2814: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 2815: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 2816: channel_free(ssh, c);
1.354 markus 2817: else
2818: c->flags |= CHAN_CLOSE_SENT;
2819: }
2820: break;
2821: }
2822: if (modified) {
2823: if ((r = sshpkt_start(ssh, type)) != 0 ||
2824: (r = sshpkt_putb(ssh, modified)) != 0 ||
2825: (r = sshpkt_send(ssh)) != 0) {
2826: error("%s: send %s", __func__, ssh_err(r));
2827: goto out;
2828: }
2829: } else {
2830: if ((r = sshpkt_start(ssh, type)) != 0 ||
2831: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2832: (r = sshpkt_send(ssh)) != 0) {
2833: error("%s: send %s", __func__, ssh_err(r));
2834: goto out;
2835: }
2836: }
2837: ret = 0;
2838: out:
2839: free(ctype);
2840: free(listen_host);
2841: sshbuf_free(original);
2842: sshbuf_free(modified);
2843: return ret;
2844: }
2845:
2846: /*
2847: * receive packets from upstream server and de-multiplex packets
2848: * to correct downstream:
2849: * implemented as a helper for channel input handlers,
2850: * replaces local (proxy) channel ID with downstream channel ID.
2851: */
2852: int
1.363 markus 2853: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 2854: {
2855: struct sshbuf *b = NULL;
2856: Channel *downstream;
2857: const u_char *cp = NULL;
2858: size_t len;
2859: int r;
2860:
2861: /*
2862: * When receiving packets from the peer we need to check whether we
2863: * need to forward the packets to the mux client. In this case we
1.380 djm 2864: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 2865: * so we can cleanup the channel.
2866: */
2867: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2868: return 0;
2869: if ((downstream = c->mux_ctx) == NULL)
2870: return 0;
2871: switch (type) {
2872: case SSH2_MSG_CHANNEL_CLOSE:
2873: case SSH2_MSG_CHANNEL_DATA:
2874: case SSH2_MSG_CHANNEL_EOF:
2875: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2876: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2877: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2878: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2879: case SSH2_MSG_CHANNEL_SUCCESS:
2880: case SSH2_MSG_CHANNEL_FAILURE:
2881: case SSH2_MSG_CHANNEL_REQUEST:
2882: break;
2883: default:
2884: debug2("%s: channel %u: unsupported type %u", __func__,
2885: c->self, type);
2886: return 0;
2887: }
2888: if ((b = sshbuf_new()) == NULL) {
2889: error("%s: alloc reply", __func__);
2890: goto out;
2891: }
2892: /* get remaining payload (after id) */
2893: cp = sshpkt_ptr(ssh, &len);
2894: if (cp == NULL) {
2895: error("%s: no packet", __func__);
2896: goto out;
2897: }
2898: /* translate id and send to muxclient */
2899: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2900: (r = sshbuf_put_u8(b, type)) != 0 ||
2901: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2902: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 2903: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.354 markus 2904: error("%s: compose for muxclient %s", __func__, ssh_err(r));
2905: goto out;
2906: }
2907: /* sshbuf_dump(b, stderr); */
2908: if (ssh_packet_log_type(type))
2909: debug3("%s: channel %u: up->down: type %u", __func__, c->self,
2910: type);
2911: out:
2912: /* update state */
2913: switch (type) {
2914: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2915: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 2916: if (cp && len > 4) {
1.354 markus 2917: c->remote_id = PEEK_U32(cp);
1.368 djm 2918: c->have_remote_id = 1;
2919: }
1.354 markus 2920: break;
2921: case SSH2_MSG_CHANNEL_CLOSE:
2922: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 2923: channel_free(ssh, c);
1.354 markus 2924: else
2925: c->flags |= CHAN_CLOSE_RCVD;
2926: break;
2927: }
2928: sshbuf_free(b);
2929: return 1;
2930: }
1.121 markus 2931:
2932: /* -- protocol input */
1.249 djm 2933:
1.367 djm 2934: /* Parse a channel ID from the current packet */
2935: static int
2936: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
2937: {
2938: u_int32_t id;
2939: int r;
2940:
2941: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
2942: error("%s: parse id: %s", where, ssh_err(r));
2943: ssh_packet_disconnect(ssh, "Invalid %s message", what);
2944: }
2945: if (id > INT_MAX) {
2946: error("%s: bad channel id %u: %s", where, id, ssh_err(r));
2947: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
2948: }
2949: return (int)id;
2950: }
2951:
2952: /* Lookup a channel from an ID in the current packet */
2953: static Channel *
2954: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
2955: {
2956: int id = channel_parse_id(ssh, where, what);
2957: Channel *c;
2958:
2959: if ((c = channel_lookup(ssh, id)) == NULL) {
2960: ssh_packet_disconnect(ssh,
2961: "%s packet referred to nonexistent channel %d", what, id);
2962: }
2963: return c;
2964: }
2965:
1.339 markus 2966: int
1.363 markus 2967: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2968: {
1.332 djm 2969: const u_char *data;
1.367 djm 2970: size_t data_len, win_len;
2971: Channel *c = channel_from_packet_id(ssh, __func__, "data");
2972: int r;
1.25 markus 2973:
1.363 markus 2974: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2975: return 0;
1.25 markus 2976:
2977: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2978: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 2979: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
2980: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 2981: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2982: return 0;
1.37 markus 2983:
1.25 markus 2984: /* Get the data. */
1.389 djm 2985: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
2986: (r = sshpkt_get_end(ssh)) != 0)
1.367 djm 2987: fatal("%s: channel %d: get data: %s", __func__,
2988: c->self, ssh_err(r));
2989:
1.309 djm 2990: win_len = data_len;
2991: if (c->datagram)
2992: win_len += 4; /* string length header */
1.200 markus 2993:
2994: /*
1.367 djm 2995: * The sending side reduces its window as it sends data, so we
2996: * must 'fake' consumption of the data in order to ensure that window
2997: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 2998: */
1.358 djm 2999: if (c->ostate != CHAN_OUTPUT_OPEN) {
3000: c->local_window -= win_len;
3001: c->local_consumed += win_len;
1.339 markus 3002: return 0;
1.200 markus 3003: }
1.41 markus 3004:
1.358 djm 3005: if (win_len > c->local_maxpacket) {
1.367 djm 3006: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 3007: c->self, win_len, c->local_maxpacket);
1.367 djm 3008: return 0;
1.358 djm 3009: }
3010: if (win_len > c->local_window) {
1.367 djm 3011: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 3012: c->self, win_len, c->local_window);
3013: return 0;
1.44 markus 3014: }
1.358 djm 3015: c->local_window -= win_len;
3016:
1.367 djm 3017: if (c->datagram) {
3018: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
3019: fatal("%s: channel %d: append datagram: %s",
3020: __func__, c->self, ssh_err(r));
3021: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
3022: fatal("%s: channel %d: append data: %s",
3023: __func__, c->self, ssh_err(r));
3024:
1.339 markus 3025: return 0;
1.1 deraadt 3026: }
1.121 markus 3027:
1.339 markus 3028: int
1.363 markus 3029: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 3030: {
1.367 djm 3031: const u_char *data;
3032: size_t data_len;
3033: u_int32_t tcode;
3034: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
3035: int r;
1.44 markus 3036:
1.363 markus 3037: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3038: return 0;
1.44 markus 3039: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 3040: logit("channel %d: ext data for non open", c->self);
1.339 markus 3041: return 0;
1.172 markus 3042: }
3043: if (c->flags & CHAN_EOF_RCVD) {
3044: if (datafellows & SSH_BUG_EXTEOF)
1.367 djm 3045: debug("channel %d: accepting ext data after eof",
3046: c->self);
1.172 markus 3047: else
1.367 djm 3048: ssh_packet_disconnect(ssh, "Received extended_data "
3049: "after EOF on channel %d.", c->self);
3050: }
3051:
3052: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
3053: error("%s: parse tcode: %s", __func__, ssh_err(r));
3054: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3055: }
3056: if (c->efd == -1 ||
3057: c->extended_usage != CHAN_EXTENDED_WRITE ||
3058: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3059: logit("channel %d: bad ext data", c->self);
1.339 markus 3060: return 0;
1.44 markus 3061: }
1.389 djm 3062: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3063: (r = sshpkt_get_end(ssh)) != 0) {
1.367 djm 3064: error("%s: parse data: %s", __func__, ssh_err(r));
3065: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3066: }
3067:
1.44 markus 3068: if (data_len > c->local_window) {
1.367 djm 3069: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3070: c->self, data_len, c->local_window);
1.339 markus 3071: return 0;
1.44 markus 3072: }
1.367 djm 3073: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3074: /* XXX sshpkt_getb? */
3075: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
3076: error("%s: append: %s", __func__, ssh_err(r));
1.44 markus 3077: c->local_window -= data_len;
1.339 markus 3078: return 0;
1.44 markus 3079: }
3080:
1.339 markus 3081: int
1.363 markus 3082: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3083: {
1.367 djm 3084: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3085: int r;
1.367 djm 3086:
1.389 djm 3087: if ((r = sshpkt_get_end(ssh)) != 0) {
3088: error("%s: parse data: %s", __func__, ssh_err(r));
3089: ssh_packet_disconnect(ssh, "Invalid ieof message");
3090: }
1.41 markus 3091:
1.363 markus 3092: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3093: return 0;
1.367 djm 3094: chan_rcvd_ieof(ssh, c);
1.133 markus 3095:
3096: /* XXX force input close */
1.156 markus 3097: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3098: debug("channel %d: FORCE input drain", c->self);
3099: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3100: if (sshbuf_len(c->input) == 0)
3101: chan_ibuf_empty(ssh, c);
1.133 markus 3102: }
1.339 markus 3103: return 0;
1.41 markus 3104: }
1.1 deraadt 3105:
1.339 markus 3106: int
1.363 markus 3107: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3108: {
1.367 djm 3109: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3110: int r;
1.151 markus 3111:
1.363 markus 3112: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3113: return 0;
1.389 djm 3114: if ((r = sshpkt_get_end(ssh)) != 0) {
3115: error("%s: parse data: %s", __func__, ssh_err(r));
3116: ssh_packet_disconnect(ssh, "Invalid oclose message");
3117: }
1.367 djm 3118: chan_rcvd_oclose(ssh, c);
1.339 markus 3119: return 0;
1.1 deraadt 3120: }
3121:
1.339 markus 3122: int
1.363 markus 3123: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3124: {
1.367 djm 3125: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3126: u_int32_t remote_window, remote_maxpacket;
3127: int r;
1.25 markus 3128:
1.363 markus 3129: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3130: return 0;
3131: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3132: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3133: "non-opening channel %d.", c->self);
3134: /*
3135: * Record the remote channel number and mark that the channel
3136: * is now open.
3137: */
1.368 djm 3138: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3139: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3140: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3141: (r = sshpkt_get_end(ssh)) != 0) {
1.367 djm 3142: error("%s: window/maxpacket: %s", __func__, ssh_err(r));
1.389 djm 3143: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3144: }
3145:
1.368 djm 3146: c->have_remote_id = 1;
1.367 djm 3147: c->remote_window = remote_window;
3148: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3149: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3150: if (c->open_confirm) {
1.367 djm 3151: debug2("%s: channel %d: callback start", __func__, c->self);
3152: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
3153: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3154: }
1.358 djm 3155: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3156: c->remote_window, c->remote_maxpacket);
1.339 markus 3157: return 0;
1.1 deraadt 3158: }
3159:
1.127 itojun 3160: static char *
1.114 markus 3161: reason2txt(int reason)
3162: {
1.143 deraadt 3163: switch (reason) {
1.114 markus 3164: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3165: return "administratively prohibited";
3166: case SSH2_OPEN_CONNECT_FAILED:
3167: return "connect failed";
3168: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3169: return "unknown channel type";
3170: case SSH2_OPEN_RESOURCE_SHORTAGE:
3171: return "resource shortage";
3172: }
1.117 stevesk 3173: return "unknown reason";
1.114 markus 3174: }
3175:
1.339 markus 3176: int
1.363 markus 3177: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3178: {
1.367 djm 3179: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3180: u_int32_t reason;
3181: char *msg = NULL;
3182: int r;
1.25 markus 3183:
1.363 markus 3184: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3185: return 0;
3186: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3187: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3188: "non-opening channel %d.", c->self);
3189: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
3190: error("%s: reason: %s", __func__, ssh_err(r));
1.389 djm 3191: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3192: }
1.378 djm 3193: /* skip language */
3194: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3195: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3196: (r = sshpkt_get_end(ssh)) != 0) {
1.378 djm 3197: error("%s: message/lang: %s", __func__, ssh_err(r));
1.389 djm 3198: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3199: }
1.367 djm 3200: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3201: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3202: free(msg);
3203: if (c->open_confirm) {
1.367 djm 3204: debug2("%s: channel %d: callback start", __func__, c->self);
3205: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
3206: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3207: }
1.291 djm 3208: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3209: chan_mark_dead(ssh, c);
1.339 markus 3210: return 0;
1.44 markus 3211: }
3212:
1.339 markus 3213: int
1.363 markus 3214: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3215: {
1.367 djm 3216: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3217: Channel *c;
1.367 djm 3218: u_int32_t adjust;
3219: u_int new_rwin;
3220: int r;
1.1 deraadt 3221:
1.367 djm 3222: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3223: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3224: return 0;
1.372 markus 3225: }
1.367 djm 3226:
1.363 markus 3227: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3228: return 0;
1.389 djm 3229: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3230: (r = sshpkt_get_end(ssh)) != 0) {
1.367 djm 3231: error("%s: adjust: %s", __func__, ssh_err(r));
1.389 djm 3232: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3233: }
3234: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3235: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3236: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3237: c->self, adjust, c->remote_window);
3238: }
3239: c->remote_window = new_rwin;
1.339 markus 3240: return 0;
1.121 markus 3241: }
1.1 deraadt 3242:
1.339 markus 3243: int
1.363 markus 3244: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3245: {
1.367 djm 3246: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3247: Channel *c;
3248: struct channel_confirm *cc;
3249:
3250: /* Reset keepalive timeout */
1.389 djm 3251: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3252:
1.367 djm 3253: debug2("%s: type %d id %d", __func__, type, id);
1.275 djm 3254:
1.367 djm 3255: if ((c = channel_lookup(ssh, id)) == NULL) {
3256: logit("%s: %d: unknown", __func__, id);
1.339 markus 3257: return 0;
1.367 djm 3258: }
1.363 markus 3259: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3260: return 0;
1.394 dtucker 3261: if (sshpkt_get_end(ssh) != 0)
1.389 djm 3262: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3263: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3264: return 0;
1.367 djm 3265: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3266: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 3267: freezero(cc, sizeof(*cc));
1.339 markus 3268: return 0;
1.275 djm 3269: }
1.121 markus 3270:
3271: /* -- tcp forwarding */
1.135 markus 3272:
3273: void
1.367 djm 3274: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3275: {
1.367 djm 3276: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3277: }
1.121 markus 3278:
1.312 djm 3279:
3280: /*
3281: * Determine whether or not a port forward listens to loopback, the
3282: * specified address or wildcard. On the client, a specified bind
3283: * address will always override gateway_ports. On the server, a
3284: * gateway_ports of 1 (``yes'') will override the client's specification
3285: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3286: * will bind to whatever address the client asked for.
3287: *
3288: * Special-case listen_addrs are:
3289: *
3290: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3291: * "" (empty string), "*" -> wildcard v4/v6
3292: * "localhost" -> loopback v4/v6
1.334 djm 3293: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3294: */
3295: static const char *
1.389 djm 3296: channel_fwd_bind_addr(struct ssh *ssh, const char *listen_addr, int *wildcardp,
1.336 millert 3297: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3298: {
3299: const char *addr = NULL;
3300: int wildcard = 0;
3301:
3302: if (listen_addr == NULL) {
3303: /* No address specified: default to gateway_ports setting */
1.336 millert 3304: if (fwd_opts->gateway_ports)
1.312 djm 3305: wildcard = 1;
1.336 millert 3306: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 3307: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
3308: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3309: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3310: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3311: wildcard = 1;
1.326 djm 3312: /*
3313: * Notify client if they requested a specific listen
3314: * address and it was overridden.
3315: */
3316: if (*listen_addr != '\0' &&
3317: strcmp(listen_addr, "0.0.0.0") != 0 &&
3318: strcmp(listen_addr, "*") != 0) {
1.389 djm 3319: ssh_packet_send_debug(ssh,
3320: "Forwarding listen address "
1.326 djm 3321: "\"%s\" overridden by server "
3322: "GatewayPorts", listen_addr);
3323: }
1.334 djm 3324: } else if (strcmp(listen_addr, "localhost") != 0 ||
3325: strcmp(listen_addr, "127.0.0.1") == 0 ||
3326: strcmp(listen_addr, "::1") == 0) {
1.395 djm 3327: /*
3328: * Accept explicit localhost address when
3329: * GatewayPorts=yes. The "localhost" hostname is
3330: * deliberately skipped here so it will listen on all
3331: * available local address families.
3332: */
1.334 djm 3333: addr = listen_addr;
1.326 djm 3334: }
1.334 djm 3335: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3336: strcmp(listen_addr, "::1") == 0) {
3337: /*
3338: * If a specific IPv4/IPv6 localhost address has been
3339: * requested then accept it even if gateway_ports is in
3340: * effect. This allows the client to prefer IPv4 or IPv6.
3341: */
3342: addr = listen_addr;
1.312 djm 3343: }
3344: if (wildcardp != NULL)
3345: *wildcardp = wildcard;
3346: return addr;
3347: }
3348:
1.160 markus 3349: static int
1.367 djm 3350: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3351: struct Forward *fwd, int *allocated_listen_port,
3352: struct ForwardOptions *fwd_opts)
1.25 markus 3353: {
1.113 markus 3354: Channel *c;
1.226 djm 3355: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3356: struct addrinfo hints, *ai, *aitop;
1.212 djm 3357: const char *host, *addr;
1.35 markus 3358: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3359: in_port_t *lport_p;
1.25 markus 3360:
1.212 djm 3361: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3362:
1.344 millert 3363: if (is_client && fwd->connect_path != NULL) {
3364: host = fwd->connect_path;
3365: } else {
3366: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3367: fwd->listen_host : fwd->connect_host;
3368: if (host == NULL) {
3369: error("No forward host name.");
3370: return 0;
3371: }
3372: if (strlen(host) >= NI_MAXHOST) {
3373: error("Forward host name too long.");
3374: return 0;
3375: }
1.87 markus 3376: }
1.25 markus 3377:
1.312 djm 3378: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3379: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3380: is_client, fwd_opts);
3381: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 3382: type, wildcard, (addr == NULL) ? "NULL" : addr);
3383:
3384: /*
1.35 markus 3385: * getaddrinfo returns a loopback address if the hostname is
3386: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3387: */
1.35 markus 3388: memset(&hints, 0, sizeof(hints));
1.367 djm 3389: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3390: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3391: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3392: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3393: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3394: if (addr == NULL) {
3395: /* This really shouldn't happen */
1.389 djm 3396: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3397: ssh_gai_strerror(r));
1.212 djm 3398: } else {
1.336 millert 3399: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 3400: ssh_gai_strerror(r));
1.212 djm 3401: }
1.218 markus 3402: return 0;
1.212 djm 3403: }
1.295 djm 3404: if (allocated_listen_port != NULL)
3405: *allocated_listen_port = 0;
1.35 markus 3406: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3407: switch (ai->ai_family) {
3408: case AF_INET:
3409: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3410: sin_port;
3411: break;
3412: case AF_INET6:
3413: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3414: sin6_port;
3415: break;
3416: default:
1.35 markus 3417: continue;
1.295 djm 3418: }
3419: /*
3420: * If allocating a port for -R forwards, then use the
3421: * same port for all address families.
3422: */
1.367 djm 3423: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3424: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3425: *allocated_listen_port > 0)
1.295 djm 3426: *lport_p = htons(*allocated_listen_port);
3427:
1.35 markus 3428: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3429: strport, sizeof(strport),
3430: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 3431: error("%s: getnameinfo failed", __func__);
1.35 markus 3432: continue;
3433: }
3434: /* Create a port to listen for the host. */
1.300 dtucker 3435: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 3436: if (sock == -1) {
1.35 markus 3437: /* this is no error since kernel may not support ipv6 */
1.377 djm 3438: verbose("socket [%s]:%s: %.100s", ntop, strport,
3439: strerror(errno));
1.35 markus 3440: continue;
3441: }
1.226 djm 3442:
1.376 djm 3443: set_reuseaddr(sock);
1.182 stevesk 3444:
1.295 djm 3445: debug("Local forwarding listening on %s port %s.",
3446: ntop, strport);
1.35 markus 3447:
3448: /* Bind the socket to the address. */
1.393 deraadt 3449: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3450: /*
3451: * address can be in if use ipv6 address is
3452: * already bound
3453: */
1.377 djm 3454: verbose("bind [%s]:%s: %.100s",
3455: ntop, strport, strerror(errno));
1.35 markus 3456: close(sock);
3457: continue;
3458: }
3459: /* Start listening for connections on the socket. */
1.393 deraadt 3460: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3461: error("listen [%s]:%s: %.100s", ntop, strport,
3462: strerror(errno));
1.35 markus 3463: close(sock);
3464: continue;
3465: }
1.295 djm 3466:
3467: /*
1.336 millert 3468: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3469: * record what we got.
3470: */
1.367 djm 3471: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3472: fwd->listen_port == 0 &&
1.295 djm 3473: allocated_listen_port != NULL &&
3474: *allocated_listen_port == 0) {
1.350 djm 3475: *allocated_listen_port = get_local_port(sock);
1.295 djm 3476: debug("Allocated listen port %d",
3477: *allocated_listen_port);
3478: }
3479:
1.35 markus 3480: /* Allocate a channel number for the socket. */
1.367 djm 3481: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3482: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3483: 0, "port listener", 1);
1.293 djm 3484: c->path = xstrdup(host);
1.336 millert 3485: c->host_port = fwd->connect_port;
1.312 djm 3486: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3487: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 3488: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
3489: c->listening_port = *allocated_listen_port;
3490: else
1.336 millert 3491: c->listening_port = fwd->listen_port;
1.35 markus 3492: success = 1;
3493: }
3494: if (success == 0)
1.336 millert 3495: error("%s: cannot listen to port: %d", __func__,
3496: fwd->listen_port);
1.35 markus 3497: freeaddrinfo(aitop);
1.87 markus 3498: return success;
1.25 markus 3499: }
1.1 deraadt 3500:
1.336 millert 3501: static int
1.367 djm 3502: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3503: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3504: {
3505: struct sockaddr_un sunaddr;
3506: const char *path;
3507: Channel *c;
3508: int port, sock;
3509: mode_t omask;
3510:
3511: switch (type) {
3512: case SSH_CHANNEL_UNIX_LISTENER:
3513: if (fwd->connect_path != NULL) {
3514: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3515: error("Local connecting path too long: %s",
3516: fwd->connect_path);
3517: return 0;
3518: }
3519: path = fwd->connect_path;
3520: port = PORT_STREAMLOCAL;
3521: } else {
3522: if (fwd->connect_host == NULL) {
3523: error("No forward host name.");
3524: return 0;
3525: }
3526: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3527: error("Forward host name too long.");
3528: return 0;
3529: }
3530: path = fwd->connect_host;
3531: port = fwd->connect_port;
3532: }
3533: break;
3534: case SSH_CHANNEL_RUNIX_LISTENER:
3535: path = fwd->listen_path;
3536: port = PORT_STREAMLOCAL;
3537: break;
3538: default:
3539: error("%s: unexpected channel type %d", __func__, type);
3540: return 0;
3541: }
3542:
3543: if (fwd->listen_path == NULL) {
3544: error("No forward path name.");
3545: return 0;
3546: }
3547: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3548: error("Local listening path too long: %s", fwd->listen_path);
3549: return 0;
3550: }
3551:
3552: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
3553:
3554: /* Start a Unix domain listener. */
3555: omask = umask(fwd_opts->streamlocal_bind_mask);
3556: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3557: fwd_opts->streamlocal_bind_unlink);
3558: umask(omask);
3559: if (sock < 0)
3560: return 0;
3561:
3562: debug("Local forwarding listening on path %s.", fwd->listen_path);
3563:
3564: /* Allocate a channel number for the socket. */
1.367 djm 3565: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3566: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3567: 0, "unix listener", 1);
3568: c->path = xstrdup(path);
3569: c->host_port = port;
3570: c->listening_port = PORT_STREAMLOCAL;
3571: c->listening_addr = xstrdup(fwd->listen_path);
3572: return 1;
3573: }
3574:
3575: static int
1.367 djm 3576: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3577: const char *host, u_short port)
1.202 djm 3578: {
1.209 avsm 3579: u_int i;
3580: int found = 0;
1.202 djm 3581:
1.367 djm 3582: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3583: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3584: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3585: continue;
3586: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3587: debug2("%s: close channel %d", __func__, i);
1.367 djm 3588: channel_free(ssh, c);
1.312 djm 3589: found = 1;
3590: }
3591: }
3592:
1.367 djm 3593: return found;
1.312 djm 3594: }
3595:
1.336 millert 3596: static int
1.367 djm 3597: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3598: {
3599: u_int i;
3600: int found = 0;
3601:
1.367 djm 3602: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3603: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3604: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3605: continue;
3606: if (c->path == NULL)
3607: continue;
3608: if (strcmp(c->path, path) == 0) {
3609: debug2("%s: close channel %d", __func__, i);
1.367 djm 3610: channel_free(ssh, c);
1.336 millert 3611: found = 1;
3612: }
3613: }
3614:
1.367 djm 3615: return found;
1.336 millert 3616: }
3617:
1.312 djm 3618: int
1.367 djm 3619: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3620: {
1.367 djm 3621: if (fwd->listen_path != NULL) {
3622: return channel_cancel_rport_listener_streamlocal(ssh,
3623: fwd->listen_path);
3624: } else {
3625: return channel_cancel_rport_listener_tcpip(ssh,
3626: fwd->listen_host, fwd->listen_port);
3627: }
1.336 millert 3628: }
3629:
3630: static int
1.367 djm 3631: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3632: const char *lhost, u_short lport, int cport,
3633: struct ForwardOptions *fwd_opts)
1.312 djm 3634: {
3635: u_int i;
3636: int found = 0;
1.389 djm 3637: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 3638:
1.367 djm 3639: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3640: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3641: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3642: continue;
1.313 markus 3643: if (c->listening_port != lport)
1.312 djm 3644: continue;
1.313 markus 3645: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3646: /* skip dynamic forwardings */
3647: if (c->host_port == 0)
3648: continue;
3649: } else {
3650: if (c->host_port != cport)
3651: continue;
3652: }
1.312 djm 3653: if ((c->listening_addr == NULL && addr != NULL) ||
3654: (c->listening_addr != NULL && addr == NULL))
3655: continue;
3656: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3657: debug2("%s: close channel %d", __func__, i);
1.367 djm 3658: channel_free(ssh, c);
1.202 djm 3659: found = 1;
3660: }
3661: }
3662:
1.367 djm 3663: return found;
1.202 djm 3664: }
3665:
1.336 millert 3666: static int
1.367 djm 3667: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3668: {
3669: u_int i;
3670: int found = 0;
3671:
3672: if (path == NULL) {
3673: error("%s: no path specified.", __func__);
3674: return 0;
3675: }
3676:
1.367 djm 3677: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3678: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3679: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3680: continue;
3681: if (c->listening_addr == NULL)
3682: continue;
3683: if (strcmp(c->listening_addr, path) == 0) {
3684: debug2("%s: close channel %d", __func__, i);
1.367 djm 3685: channel_free(ssh, c);
1.336 millert 3686: found = 1;
3687: }
3688: }
3689:
1.367 djm 3690: return found;
1.336 millert 3691: }
3692:
3693: int
1.367 djm 3694: channel_cancel_lport_listener(struct ssh *ssh,
3695: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3696: {
1.367 djm 3697: if (fwd->listen_path != NULL) {
3698: return channel_cancel_lport_listener_streamlocal(ssh,
3699: fwd->listen_path);
3700: } else {
3701: return channel_cancel_lport_listener_tcpip(ssh,
3702: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3703: }
1.336 millert 3704: }
3705:
1.362 markus 3706: /* protocol local port fwd, used by ssh */
1.160 markus 3707: int
1.367 djm 3708: channel_setup_local_fwd_listener(struct ssh *ssh,
3709: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3710: {
1.336 millert 3711: if (fwd->listen_path != NULL) {
1.367 djm 3712: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3713: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3714: } else {
1.367 djm 3715: return channel_setup_fwd_listener_tcpip(ssh,
3716: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3717: }
1.160 markus 3718: }
3719:
1.381 djm 3720: /* Matches a remote forwarding permission against a requested forwarding */
3721: static int
3722: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
3723: {
3724: int ret;
3725: char *lhost;
3726:
3727: /* XXX add ACLs for streamlocal */
3728: if (fwd->listen_path != NULL)
3729: return 1;
3730:
3731: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
3732: return 0;
3733:
3734: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
3735: allowed_open->listen_port != fwd->listen_port)
3736: return 0;
3737:
3738: /* Match hostnames case-insensitively */
3739: lhost = xstrdup(fwd->listen_host);
3740: lowercase(lhost);
3741: ret = match_pattern(lhost, allowed_open->listen_host);
3742: free(lhost);
3743:
3744: return ret;
3745: }
3746:
3747: /* Checks whether a requested remote forwarding is permitted */
3748: static int
3749: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
3750: {
3751: struct ssh_channels *sc = ssh->chanctxt;
3752: struct permission_set *pset = &sc->remote_perms;
3753: u_int i, permit, permit_adm = 1;
3754: struct permission *perm;
3755:
3756: /* XXX apply GatewayPorts override before checking? */
3757:
3758: permit = pset->all_permitted;
3759: if (!permit) {
3760: for (i = 0; i < pset->num_permitted_user; i++) {
3761: perm = &pset->permitted_user[i];
3762: if (remote_open_match(perm, fwd)) {
3763: permit = 1;
3764: break;
3765: }
3766: }
3767: }
3768:
3769: if (pset->num_permitted_admin > 0) {
3770: permit_adm = 0;
3771: for (i = 0; i < pset->num_permitted_admin; i++) {
3772: perm = &pset->permitted_admin[i];
3773: if (remote_open_match(perm, fwd)) {
3774: permit_adm = 1;
3775: break;
3776: }
3777: }
3778: }
3779:
3780: return permit && permit_adm;
3781: }
3782:
1.160 markus 3783: /* protocol v2 remote port fwd, used by sshd */
3784: int
1.367 djm 3785: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3786: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3787: {
1.381 djm 3788: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 3789: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 3790: if (fwd->listen_path != NULL)
3791: /* XXX always allowed, see remote_open_match() */
3792: logit("Received request from %.100s port %d to "
3793: "remote forward to path \"%.100s\", "
3794: "but the request was denied.",
3795: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3796: fwd->listen_path);
3797: else if(fwd->listen_host != NULL)
3798: logit("Received request from %.100s port %d to "
3799: "remote forward to host %.100s port %d, "
3800: "but the request was denied.",
3801: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3802: fwd->listen_host, fwd->listen_port );
3803: else
3804: logit("Received request from %.100s port %d to remote "
3805: "forward, but the request was denied.",
3806: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 3807: return 0;
3808: }
1.336 millert 3809: if (fwd->listen_path != NULL) {
1.367 djm 3810: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3811: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3812: } else {
1.367 djm 3813: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 3814: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3815: fwd_opts);
3816: }
1.160 markus 3817: }
3818:
1.27 markus 3819: /*
1.312 djm 3820: * Translate the requested rfwd listen host to something usable for
3821: * this server.
3822: */
3823: static const char *
3824: channel_rfwd_bind_host(const char *listen_host)
3825: {
3826: if (listen_host == NULL) {
1.378 djm 3827: return "localhost";
1.312 djm 3828: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 3829: return "";
1.312 djm 3830: } else
3831: return listen_host;
3832: }
3833:
3834: /*
1.27 markus 3835: * Initiate forwarding of connections to port "port" on remote host through
3836: * the secure channel to host:port from local side.
1.315 markus 3837: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 3838: * channel_update_permission().
1.27 markus 3839: */
1.253 markus 3840: int
1.367 djm 3841: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 3842: {
1.367 djm 3843: int r, success = 0, idx = -1;
3844: char *host_to_connect, *listen_host, *listen_path;
3845: int port_to_connect, listen_port;
1.73 markus 3846:
1.25 markus 3847: /* Send the forward request to the remote side. */
1.358 djm 3848: if (fwd->listen_path != NULL) {
1.367 djm 3849: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3850: (r = sshpkt_put_cstring(ssh,
3851: "streamlocal-forward@openssh.com")) != 0 ||
3852: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3853: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3854: (r = sshpkt_send(ssh)) != 0 ||
3855: (r = ssh_packet_write_wait(ssh)) != 0)
3856: fatal("%s: request streamlocal: %s",
3857: __func__, ssh_err(r));
1.336 millert 3858: } else {
1.367 djm 3859: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3860: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
3861: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3862: (r = sshpkt_put_cstring(ssh,
3863: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
3864: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
3865: (r = sshpkt_send(ssh)) != 0 ||
3866: (r = ssh_packet_write_wait(ssh)) != 0)
3867: fatal("%s: request tcpip-forward: %s",
3868: __func__, ssh_err(r));
1.73 markus 3869: }
1.358 djm 3870: /* Assume that server accepts the request */
3871: success = 1;
1.73 markus 3872: if (success) {
1.305 djm 3873: /* Record that connection to this host/port is permitted. */
1.367 djm 3874: host_to_connect = listen_host = listen_path = NULL;
3875: port_to_connect = listen_port = 0;
1.336 millert 3876: if (fwd->connect_path != NULL) {
1.367 djm 3877: host_to_connect = xstrdup(fwd->connect_path);
3878: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 3879: } else {
1.367 djm 3880: host_to_connect = xstrdup(fwd->connect_host);
3881: port_to_connect = fwd->connect_port;
1.336 millert 3882: }
3883: if (fwd->listen_path != NULL) {
1.367 djm 3884: listen_path = xstrdup(fwd->listen_path);
3885: listen_port = PORT_STREAMLOCAL;
1.336 millert 3886: } else {
1.367 djm 3887: if (fwd->listen_host != NULL)
3888: listen_host = xstrdup(fwd->listen_host);
3889: listen_port = fwd->listen_port;
3890: }
1.381 djm 3891: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 3892: host_to_connect, port_to_connect,
3893: listen_host, listen_path, listen_port, NULL);
1.44 markus 3894: }
1.367 djm 3895: return idx;
1.1 deraadt 3896: }
3897:
1.333 markus 3898: static int
1.381 djm 3899: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 3900: int requestedport)
1.333 markus 3901: {
3902: if (allowed_open->host_to_connect == NULL)
3903: return 0;
3904: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3905: allowed_open->port_to_connect != requestedport)
3906: return 0;
1.351 dtucker 3907: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3908: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3909: return 0;
3910: return 1;
3911: }
3912:
3913: /*
1.336 millert 3914: * Note that in the listen host/port case
1.333 markus 3915: * we don't support FWD_PERMIT_ANY_PORT and
3916: * need to translate between the configured-host (listen_host)
3917: * and what we've sent to the remote server (channel_rfwd_bind_host)
3918: */
3919: static int
1.381 djm 3920: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 3921: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3922: {
3923: const char *allowed_host;
3924:
3925: if (allowed_open->host_to_connect == NULL)
3926: return 0;
3927: if (allowed_open->listen_port != requestedport)
3928: return 0;
1.335 djm 3929: if (!translate && allowed_open->listen_host == NULL &&
3930: requestedhost == NULL)
3931: return 1;
1.333 markus 3932: allowed_host = translate ?
3933: channel_rfwd_bind_host(allowed_open->listen_host) :
3934: allowed_open->listen_host;
1.382 djm 3935: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 3936: strcmp(allowed_host, requestedhost) != 0)
3937: return 0;
3938: return 1;
3939: }
3940:
1.336 millert 3941: static int
1.381 djm 3942: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 3943: const char *requestedpath)
3944: {
3945: if (allowed_open->host_to_connect == NULL)
3946: return 0;
3947: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3948: return 0;
3949: if (allowed_open->listen_path == NULL ||
3950: strcmp(allowed_open->listen_path, requestedpath) != 0)
3951: return 0;
3952: return 1;
3953: }
3954:
1.27 markus 3955: /*
1.208 deraadt 3956: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3957: * local side.
3958: */
1.336 millert 3959: static int
1.367 djm 3960: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
3961: const char *host, u_short port)
1.202 djm 3962: {
1.367 djm 3963: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 3964: struct permission_set *pset = &sc->local_perms;
1.367 djm 3965: int r;
3966: u_int i;
1.397 markus 3967: struct permission *perm = NULL;
1.202 djm 3968:
1.381 djm 3969: for (i = 0; i < pset->num_permitted_user; i++) {
3970: perm = &pset->permitted_user[i];
3971: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 3972: break;
1.381 djm 3973: perm = NULL;
1.202 djm 3974: }
1.381 djm 3975: if (perm == NULL) {
1.202 djm 3976: debug("%s: requested forward not found", __func__);
1.312 djm 3977: return -1;
1.202 djm 3978: }
1.367 djm 3979: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3980: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
3981: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3982: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
3983: (r = sshpkt_put_u32(ssh, port)) != 0 ||
3984: (r = sshpkt_send(ssh)) != 0)
3985: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3986:
1.381 djm 3987: fwd_perm_clear(perm); /* unregister */
1.336 millert 3988:
3989: return 0;
3990: }
3991:
3992: /*
3993: * Request cancellation of remote forwarding of Unix domain socket
3994: * path from local side.
3995: */
3996: static int
1.367 djm 3997: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3998: {
1.367 djm 3999: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4000: struct permission_set *pset = &sc->local_perms;
1.367 djm 4001: int r;
4002: u_int i;
1.397 markus 4003: struct permission *perm = NULL;
1.336 millert 4004:
1.381 djm 4005: for (i = 0; i < pset->num_permitted_user; i++) {
4006: perm = &pset->permitted_user[i];
4007: if (open_listen_match_streamlocal(perm, path))
1.336 millert 4008: break;
1.381 djm 4009: perm = NULL;
1.336 millert 4010: }
1.381 djm 4011: if (perm == NULL) {
1.336 millert 4012: debug("%s: requested forward not found", __func__);
4013: return -1;
4014: }
1.367 djm 4015: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4016: (r = sshpkt_put_cstring(ssh,
4017: "cancel-streamlocal-forward@openssh.com")) != 0 ||
4018: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4019: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
4020: (r = sshpkt_send(ssh)) != 0)
4021: fatal("%s: send cancel: %s", __func__, ssh_err(r));
4022:
1.381 djm 4023: fwd_perm_clear(perm); /* unregister */
1.312 djm 4024:
4025: return 0;
1.202 djm 4026: }
4027:
4028: /*
1.336 millert 4029: * Request cancellation of remote forwarding of a connection from local side.
4030: */
4031: int
1.367 djm 4032: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 4033: {
4034: if (fwd->listen_path != NULL) {
1.367 djm 4035: return channel_request_rforward_cancel_streamlocal(ssh,
4036: fwd->listen_path);
1.336 millert 4037: } else {
1.367 djm 4038: return channel_request_rforward_cancel_tcpip(ssh,
4039: fwd->listen_host,
4040: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 4041: }
1.1 deraadt 4042: }
4043:
1.99 markus 4044: /*
1.381 djm 4045: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 4046: * usually called by the server, because the user could connect to any port
4047: * anyway, and the server has no way to know but to trust the client anyway.
4048: */
4049: void
1.381 djm 4050: channel_permit_all(struct ssh *ssh, int where)
4051: {
4052: struct permission_set *pset = permission_set_get(ssh, where);
4053:
4054: if (pset->num_permitted_user == 0)
4055: pset->all_permitted = 1;
4056: }
4057:
4058: /*
4059: * Permit the specified host/port for forwarding.
4060: */
4061: void
4062: channel_add_permission(struct ssh *ssh, int who, int where,
4063: char *host, int port)
4064: {
4065: int local = where == FORWARD_LOCAL;
4066: struct permission_set *pset = permission_set_get(ssh, where);
4067:
4068: debug("allow %s forwarding to host %s port %d",
4069: fwd_ident(who, where), host, port);
4070: /*
4071: * Remote forwards set listen_host/port, local forwards set
4072: * host/port_to_connect.
4073: */
4074: permission_set_add(ssh, who, where,
4075: local ? host : 0, local ? port : 0,
4076: local ? NULL : host, NULL, local ? 0 : port, NULL);
4077: pset->all_permitted = 0;
4078: }
4079:
4080: /*
4081: * Administratively disable forwarding.
4082: */
4083: void
4084: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4085: {
1.381 djm 4086: channel_clear_permission(ssh, FORWARD_ADM, where);
4087: permission_set_add(ssh, FORWARD_ADM, where,
4088: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4089: }
4090:
1.381 djm 4091: /*
4092: * Clear a list of permitted opens.
4093: */
1.101 markus 4094: void
1.381 djm 4095: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4096: {
1.381 djm 4097: struct permission **permp;
4098: u_int *npermp;
1.367 djm 4099:
1.381 djm 4100: permission_set_get_array(ssh, who, where, &permp, &npermp);
4101: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4102: *npermp = 0;
1.315 markus 4103: }
4104:
4105: /*
4106: * Update the listen port for a dynamic remote forward, after
4107: * the actual 'newport' has been allocated. If 'newport' < 0 is
4108: * passed then they entry will be invalidated.
4109: */
4110: void
1.381 djm 4111: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4112: {
1.381 djm 4113: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4114:
1.381 djm 4115: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
4116: debug("%s: index out of range: %d num_permitted_user %d",
4117: __func__, idx, pset->num_permitted_user);
1.315 markus 4118: return;
4119: }
4120: debug("%s allowed port %d for forwarding to host %s port %d",
4121: newport > 0 ? "Updating" : "Removing",
4122: newport,
1.381 djm 4123: pset->permitted_user[idx].host_to_connect,
4124: pset->permitted_user[idx].port_to_connect);
1.367 djm 4125: if (newport <= 0)
1.381 djm 4126: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4127: else {
1.381 djm 4128: pset->permitted_user[idx].listen_port =
1.315 markus 4129: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
4130: }
1.99 markus 4131: }
4132:
1.314 dtucker 4133: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4134: int
4135: permitopen_port(const char *p)
4136: {
4137: int port;
4138:
4139: if (strcmp(p, "*") == 0)
4140: return FWD_PERMIT_ANY_PORT;
4141: if ((port = a2port(p)) > 0)
4142: return port;
4143: return -1;
4144: }
4145:
1.276 djm 4146: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4147: static int
1.276 djm 4148: connect_next(struct channel_connect *cctx)
1.41 markus 4149: {
1.276 djm 4150: int sock, saved_errno;
1.336 millert 4151: struct sockaddr_un *sunaddr;
1.367 djm 4152: char ntop[NI_MAXHOST];
4153: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4154:
1.276 djm 4155: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4156: switch (cctx->ai->ai_family) {
4157: case AF_UNIX:
4158: /* unix:pathname instead of host:port */
4159: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4160: strlcpy(ntop, "unix", sizeof(ntop));
4161: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4162: break;
4163: case AF_INET:
4164: case AF_INET6:
4165: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4166: ntop, sizeof(ntop), strport, sizeof(strport),
4167: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
4168: error("connect_next: getnameinfo failed");
4169: continue;
4170: }
4171: break;
4172: default:
1.41 markus 4173: continue;
4174: }
1.300 dtucker 4175: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4176: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4177: if (cctx->ai->ai_next == NULL)
1.186 djm 4178: error("socket: %.100s", strerror(errno));
4179: else
4180: verbose("socket: %.100s", strerror(errno));
1.41 markus 4181: continue;
4182: }
1.205 djm 4183: if (set_nonblock(sock) == -1)
4184: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 4185: if (connect(sock, cctx->ai->ai_addr,
4186: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
4187: debug("connect_next: host %.100s ([%.100s]:%s): "
4188: "%.100s", cctx->host, ntop, strport,
1.41 markus 4189: strerror(errno));
1.276 djm 4190: saved_errno = errno;
1.41 markus 4191: close(sock);
1.276 djm 4192: errno = saved_errno;
1.89 stevesk 4193: continue; /* fail -- try next */
1.41 markus 4194: }
1.336 millert 4195: if (cctx->ai->ai_family != AF_UNIX)
4196: set_nodelay(sock);
1.276 djm 4197: debug("connect_next: host %.100s ([%.100s]:%s) "
4198: "in progress, fd=%d", cctx->host, ntop, strport, sock);
4199: cctx->ai = cctx->ai->ai_next;
4200: return sock;
4201: }
4202: return -1;
4203: }
1.41 markus 4204:
1.276 djm 4205: static void
4206: channel_connect_ctx_free(struct channel_connect *cctx)
4207: {
1.321 djm 4208: free(cctx->host);
1.336 millert 4209: if (cctx->aitop) {
4210: if (cctx->aitop->ai_family == AF_UNIX)
4211: free(cctx->aitop);
4212: else
4213: freeaddrinfo(cctx->aitop);
4214: }
1.329 tedu 4215: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4216: }
4217:
1.357 dtucker 4218: /*
1.372 markus 4219: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4220: * passing back the failure reason if appropriate.
4221: */
1.372 markus 4222: static int
4223: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4224: char *ctype, char *rname, struct channel_connect *cctx,
4225: int *reason, const char **errmsg)
1.276 djm 4226: {
4227: struct addrinfo hints;
4228: int gaierr;
4229: int sock = -1;
4230: char strport[NI_MAXSERV];
1.336 millert 4231:
4232: if (port == PORT_STREAMLOCAL) {
4233: struct sockaddr_un *sunaddr;
4234: struct addrinfo *ai;
4235:
4236: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4237: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4238: return -1;
1.336 millert 4239: }
4240:
4241: /*
4242: * Fake up a struct addrinfo for AF_UNIX connections.
4243: * channel_connect_ctx_free() must check ai_family
4244: * and use free() not freeaddirinfo() for AF_UNIX.
4245: */
4246: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4247: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4248: ai->ai_addr = (struct sockaddr *)(ai + 1);
4249: ai->ai_addrlen = sizeof(*sunaddr);
4250: ai->ai_family = AF_UNIX;
1.372 markus 4251: ai->ai_socktype = socktype;
1.336 millert 4252: ai->ai_protocol = PF_UNSPEC;
4253: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4254: sunaddr->sun_family = AF_UNIX;
4255: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4256: cctx->aitop = ai;
1.336 millert 4257: } else {
4258: memset(&hints, 0, sizeof(hints));
1.367 djm 4259: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4260: hints.ai_socktype = socktype;
1.336 millert 4261: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4262: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4263: != 0) {
4264: if (errmsg != NULL)
4265: *errmsg = ssh_gai_strerror(gaierr);
4266: if (reason != NULL)
4267: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4268: error("connect_to %.100s: unknown host (%s)", name,
4269: ssh_gai_strerror(gaierr));
1.372 markus 4270: return -1;
1.336 millert 4271: }
1.41 markus 4272: }
1.276 djm 4273:
1.372 markus 4274: cctx->host = xstrdup(name);
4275: cctx->port = port;
4276: cctx->ai = cctx->aitop;
1.276 djm 4277:
1.372 markus 4278: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4279: error("connect to %.100s port %d failed: %s",
1.336 millert 4280: name, port, strerror(errno));
1.372 markus 4281: return -1;
4282: }
4283:
4284: return sock;
4285: }
4286:
4287: /* Return CONNECTING channel to remote host:port or local socket path */
4288: static Channel *
4289: connect_to(struct ssh *ssh, const char *host, int port,
4290: char *ctype, char *rname)
4291: {
4292: struct channel_connect cctx;
4293: Channel *c;
4294: int sock;
4295:
4296: memset(&cctx, 0, sizeof(cctx));
4297: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4298: &cctx, NULL, NULL);
4299: if (sock == -1) {
1.276 djm 4300: channel_connect_ctx_free(&cctx);
4301: return NULL;
1.41 markus 4302: }
1.367 djm 4303: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4304: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4305: c->host_port = port;
4306: c->path = xstrdup(host);
1.276 djm 4307: c->connect_ctx = cctx;
1.372 markus 4308:
1.276 djm 4309: return c;
1.41 markus 4310: }
1.99 markus 4311:
1.354 markus 4312: /*
4313: * returns either the newly connected channel or the downstream channel
4314: * that needs to deal with this connection.
4315: */
1.276 djm 4316: Channel *
1.367 djm 4317: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4318: u_short listen_port, char *ctype, char *rname)
1.73 markus 4319: {
1.367 djm 4320: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4321: struct permission_set *pset = &sc->local_perms;
1.367 djm 4322: u_int i;
1.381 djm 4323: struct permission *perm;
1.99 markus 4324:
1.381 djm 4325: for (i = 0; i < pset->num_permitted_user; i++) {
4326: perm = &pset->permitted_user[i];
4327: if (open_listen_match_tcpip(perm,
4328: listen_host, listen_port, 1)) {
4329: if (perm->downstream)
4330: return perm->downstream;
4331: if (perm->port_to_connect == 0)
1.372 markus 4332: return rdynamic_connect_prepare(ssh,
4333: ctype, rname);
1.367 djm 4334: return connect_to(ssh,
1.381 djm 4335: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4336: ctype, rname);
1.276 djm 4337: }
4338: }
1.74 markus 4339: error("WARNING: Server requests forwarding for unknown listen_port %d",
4340: listen_port);
1.276 djm 4341: return NULL;
1.73 markus 4342: }
4343:
1.336 millert 4344: Channel *
1.367 djm 4345: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4346: char *ctype, char *rname)
1.336 millert 4347: {
1.367 djm 4348: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4349: struct permission_set *pset = &sc->local_perms;
1.367 djm 4350: u_int i;
1.381 djm 4351: struct permission *perm;
1.336 millert 4352:
1.381 djm 4353: for (i = 0; i < pset->num_permitted_user; i++) {
4354: perm = &pset->permitted_user[i];
4355: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4356: return connect_to(ssh,
1.381 djm 4357: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4358: ctype, rname);
1.336 millert 4359: }
4360: }
4361: error("WARNING: Server requests forwarding for unknown path %.100s",
4362: path);
4363: return NULL;
4364: }
4365:
1.99 markus 4366: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4367: Channel *
1.367 djm 4368: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4369: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4370: {
1.367 djm 4371: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4372: struct permission_set *pset = &sc->local_perms;
1.372 markus 4373: struct channel_connect cctx;
4374: Channel *c;
1.367 djm 4375: u_int i, permit, permit_adm = 1;
1.372 markus 4376: int sock;
1.381 djm 4377: struct permission *perm;
1.99 markus 4378:
1.381 djm 4379: permit = pset->all_permitted;
1.99 markus 4380: if (!permit) {
1.381 djm 4381: for (i = 0; i < pset->num_permitted_user; i++) {
4382: perm = &pset->permitted_user[i];
4383: if (open_match(perm, host, port)) {
1.99 markus 4384: permit = 1;
1.333 markus 4385: break;
4386: }
1.367 djm 4387: }
1.257 dtucker 4388: }
1.99 markus 4389:
1.381 djm 4390: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4391: permit_adm = 0;
1.381 djm 4392: for (i = 0; i < pset->num_permitted_admin; i++) {
4393: perm = &pset->permitted_admin[i];
4394: if (open_match(perm, host, port)) {
1.257 dtucker 4395: permit_adm = 1;
1.333 markus 4396: break;
4397: }
1.367 djm 4398: }
1.99 markus 4399: }
1.257 dtucker 4400:
4401: if (!permit || !permit_adm) {
1.391 florian 4402: logit("Received request from %.100s port %d to connect to "
4403: "host %.100s port %d, but the request was denied.",
4404: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4405: if (reason != NULL)
4406: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4407: return NULL;
1.99 markus 4408: }
1.372 markus 4409:
4410: memset(&cctx, 0, sizeof(cctx));
4411: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4412: &cctx, reason, errmsg);
4413: if (sock == -1) {
4414: channel_connect_ctx_free(&cctx);
4415: return NULL;
4416: }
4417:
4418: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4419: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4420: c->host_port = port;
4421: c->path = xstrdup(host);
4422: c->connect_ctx = cctx;
4423:
4424: return c;
1.336 millert 4425: }
4426:
4427: /* Check if connecting to that path is permitted and connect. */
4428: Channel *
1.367 djm 4429: channel_connect_to_path(struct ssh *ssh, const char *path,
4430: char *ctype, char *rname)
1.336 millert 4431: {
1.367 djm 4432: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4433: struct permission_set *pset = &sc->local_perms;
1.367 djm 4434: u_int i, permit, permit_adm = 1;
1.381 djm 4435: struct permission *perm;
1.336 millert 4436:
1.381 djm 4437: permit = pset->all_permitted;
1.336 millert 4438: if (!permit) {
1.381 djm 4439: for (i = 0; i < pset->num_permitted_user; i++) {
4440: perm = &pset->permitted_user[i];
4441: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4442: permit = 1;
4443: break;
4444: }
1.367 djm 4445: }
1.336 millert 4446: }
4447:
1.381 djm 4448: if (pset->num_permitted_admin > 0) {
1.336 millert 4449: permit_adm = 0;
1.381 djm 4450: for (i = 0; i < pset->num_permitted_admin; i++) {
4451: perm = &pset->permitted_admin[i];
4452: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4453: permit_adm = 1;
4454: break;
4455: }
1.367 djm 4456: }
1.336 millert 4457: }
4458:
4459: if (!permit || !permit_adm) {
4460: logit("Received request to connect to path %.100s, "
4461: "but the request was denied.", path);
4462: return NULL;
4463: }
1.367 djm 4464: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4465: }
4466:
4467: void
1.367 djm 4468: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4469: {
1.367 djm 4470: struct ssh_channels *sc = ssh->chanctxt;
4471: struct winsize ws;
4472: int r;
1.209 avsm 4473: u_int i;
1.204 djm 4474:
1.367 djm 4475: for (i = 0; i < sc->channels_alloc; i++) {
4476: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4477: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4478: continue;
1.393 deraadt 4479: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4480: continue;
1.367 djm 4481: channel_request_start(ssh, i, "window-change", 0);
4482: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4483: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4484: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4485: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4486: (r = sshpkt_send(ssh)) != 0)
4487: fatal("%s: channel %u: send window-change: %s",
4488: __func__, i, ssh_err(r));
1.204 djm 4489: }
1.372 markus 4490: }
4491:
4492: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4493: static Channel *
4494: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4495: {
4496: Channel *c;
4497: int r;
4498:
4499: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4500: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4501: c->host_port = 0;
4502: c->path = NULL;
4503:
4504: /*
4505: * We need to open the channel before we have a FD,
4506: * so that we can get SOCKS header from peer.
4507: */
4508: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4509: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4510: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4511: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
4512: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
4513: fatal("%s: channel %i: confirm: %s", __func__,
4514: c->self, ssh_err(r));
4515: }
4516: return c;
4517: }
4518:
4519: /* Return CONNECTING socket to remote host:port or local socket path */
4520: static int
4521: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4522: {
4523: struct channel_connect cctx;
4524: int sock;
4525:
4526: memset(&cctx, 0, sizeof(cctx));
4527: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4528: NULL, &cctx, NULL, NULL);
4529: if (sock == -1)
4530: channel_connect_ctx_free(&cctx);
4531: else {
4532: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4533: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4534: c->connect_ctx = cctx;
4535: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4536: }
4537: return sock;
1.99 markus 4538: }
4539:
1.121 markus 4540: /* -- X11 forwarding */
1.1 deraadt 4541:
1.27 markus 4542: /*
4543: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4544: * Returns 0 and a suitable display number for the DISPLAY variable
4545: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4546: */
1.141 stevesk 4547: int
1.367 djm 4548: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4549: int x11_use_localhost, int single_connection,
4550: u_int *display_numberp, int **chanids)
1.1 deraadt 4551: {
1.149 markus 4552: Channel *nc = NULL;
1.31 markus 4553: int display_number, sock;
4554: u_short port;
1.35 markus 4555: struct addrinfo hints, *ai, *aitop;
4556: char strport[NI_MAXSERV];
4557: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4558:
1.224 markus 4559: if (chanids == NULL)
4560: return -1;
4561:
1.33 markus 4562: for (display_number = x11_display_offset;
1.148 deraadt 4563: display_number < MAX_DISPLAYS;
4564: display_number++) {
1.25 markus 4565: port = 6000 + display_number;
1.35 markus 4566: memset(&hints, 0, sizeof(hints));
1.367 djm 4567: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4568: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4569: hints.ai_socktype = SOCK_STREAM;
4570: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4571: if ((gaierr = getaddrinfo(NULL, strport,
4572: &hints, &aitop)) != 0) {
1.271 dtucker 4573: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4574: return -1;
1.25 markus 4575: }
1.35 markus 4576: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4577: if (ai->ai_family != AF_INET &&
4578: ai->ai_family != AF_INET6)
1.35 markus 4579: continue;
1.300 dtucker 4580: sock = socket(ai->ai_family, ai->ai_socktype,
4581: ai->ai_protocol);
1.393 deraadt 4582: if (sock == -1) {
1.35 markus 4583: error("socket: %.100s", strerror(errno));
1.203 markus 4584: freeaddrinfo(aitop);
1.141 stevesk 4585: return -1;
1.35 markus 4586: }
1.376 djm 4587: set_reuseaddr(sock);
1.393 deraadt 4588: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 4589: debug2("%s: bind port %d: %.100s", __func__,
4590: port, strerror(errno));
1.35 markus 4591: close(sock);
1.367 djm 4592: for (n = 0; n < num_socks; n++)
1.35 markus 4593: close(socks[n]);
4594: num_socks = 0;
4595: break;
4596: }
4597: socks[num_socks++] = sock;
4598: if (num_socks == NUM_SOCKS)
4599: break;
1.25 markus 4600: }
1.83 stevesk 4601: freeaddrinfo(aitop);
1.35 markus 4602: if (num_socks > 0)
4603: break;
1.25 markus 4604: }
4605: if (display_number >= MAX_DISPLAYS) {
4606: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4607: return -1;
1.25 markus 4608: }
4609: /* Start listening for connections on the socket. */
1.35 markus 4610: for (n = 0; n < num_socks; n++) {
4611: sock = socks[n];
1.393 deraadt 4612: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 4613: error("listen: %.100s", strerror(errno));
4614: close(sock);
1.141 stevesk 4615: return -1;
1.35 markus 4616: }
1.25 markus 4617: }
1.35 markus 4618:
4619: /* Allocate a channel for each socket. */
1.242 djm 4620: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4621: for (n = 0; n < num_socks; n++) {
4622: sock = socks[n];
1.367 djm 4623: nc = channel_new(ssh, "x11 listener",
1.51 markus 4624: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4625: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4626: 0, "X11 inet listener", 1);
1.167 markus 4627: nc->single_connection = single_connection;
1.224 markus 4628: (*chanids)[n] = nc->self;
1.35 markus 4629: }
1.224 markus 4630: (*chanids)[n] = -1;
1.1 deraadt 4631:
1.141 stevesk 4632: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4633: *display_numberp = display_number;
1.367 djm 4634: return 0;
1.1 deraadt 4635: }
4636:
1.127 itojun 4637: static int
1.77 markus 4638: connect_local_xsocket(u_int dnr)
1.1 deraadt 4639: {
1.25 markus 4640: int sock;
4641: struct sockaddr_un addr;
4642:
1.147 stevesk 4643: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 deraadt 4644: if (sock == -1)
1.147 stevesk 4645: error("socket: %.100s", strerror(errno));
4646: memset(&addr, 0, sizeof(addr));
4647: addr.sun_family = AF_UNIX;
4648: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4649: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4650: return sock;
4651: close(sock);
1.25 markus 4652: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4653: return -1;
1.1 deraadt 4654: }
4655:
1.51 markus 4656: int
1.367 djm 4657: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4658: {
1.248 deraadt 4659: u_int display_number;
1.25 markus 4660: const char *display;
1.51 markus 4661: char buf[1024], *cp;
1.35 markus 4662: struct addrinfo hints, *ai, *aitop;
4663: char strport[NI_MAXSERV];
1.248 deraadt 4664: int gaierr, sock = 0;
1.25 markus 4665:
4666: /* Try to open a socket for the local X server. */
4667: display = getenv("DISPLAY");
4668: if (!display) {
4669: error("DISPLAY not set.");
1.51 markus 4670: return -1;
1.25 markus 4671: }
1.27 markus 4672: /*
4673: * Now we decode the value of the DISPLAY variable and make a
4674: * connection to the real X server.
4675: */
4676:
4677: /*
4678: * Check if it is a unix domain socket. Unix domain displays are in
4679: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4680: */
1.25 markus 4681: if (strncmp(display, "unix:", 5) == 0 ||
4682: display[0] == ':') {
4683: /* Connect to the unix domain socket. */
1.367 djm 4684: if (sscanf(strrchr(display, ':') + 1, "%u",
4685: &display_number) != 1) {
4686: error("Could not parse display number from DISPLAY: "
4687: "%.100s", display);
1.51 markus 4688: return -1;
1.25 markus 4689: }
4690: /* Create a socket. */
4691: sock = connect_local_xsocket(display_number);
4692: if (sock < 0)
1.51 markus 4693: return -1;
1.25 markus 4694:
4695: /* OK, we now have a connection to the display. */
1.51 markus 4696: return sock;
1.25 markus 4697: }
1.27 markus 4698: /*
4699: * Connect to an inet socket. The DISPLAY value is supposedly
4700: * hostname:d[.s], where hostname may also be numeric IP address.
4701: */
1.145 stevesk 4702: strlcpy(buf, display, sizeof(buf));
1.25 markus 4703: cp = strchr(buf, ':');
4704: if (!cp) {
4705: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4706: return -1;
1.25 markus 4707: }
4708: *cp = 0;
1.367 djm 4709: /*
4710: * buf now contains the host name. But first we parse the
4711: * display number.
4712: */
1.248 deraadt 4713: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4714: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4715: display);
1.51 markus 4716: return -1;
1.25 markus 4717: }
1.35 markus 4718:
4719: /* Look up the host address */
4720: memset(&hints, 0, sizeof(hints));
1.367 djm 4721: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4722: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4723: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4724: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4725: error("%.100s: unknown host. (%s)", buf,
4726: ssh_gai_strerror(gaierr));
1.51 markus 4727: return -1;
1.25 markus 4728: }
1.35 markus 4729: for (ai = aitop; ai; ai = ai->ai_next) {
4730: /* Create a socket. */
1.300 dtucker 4731: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 4732: if (sock == -1) {
1.194 markus 4733: debug2("socket: %.100s", strerror(errno));
1.41 markus 4734: continue;
4735: }
4736: /* Connect it to the display. */
1.393 deraadt 4737: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 4738: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4739: 6000 + display_number, strerror(errno));
4740: close(sock);
4741: continue;
4742: }
4743: /* Success */
4744: break;
1.35 markus 4745: }
4746: freeaddrinfo(aitop);
4747: if (!ai) {
1.367 djm 4748: error("connect %.100s port %u: %.100s", buf,
4749: 6000 + display_number, strerror(errno));
1.51 markus 4750: return -1;
1.25 markus 4751: }
1.162 stevesk 4752: set_nodelay(sock);
1.51 markus 4753: return sock;
4754: }
4755:
4756: /*
1.27 markus 4757: * Requests forwarding of X11 connections, generates fake authentication
4758: * data, and enables authentication spoofing.
1.121 markus 4759: * This should be called in the client only.
1.27 markus 4760: */
1.49 markus 4761: void
1.367 djm 4762: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4763: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4764: {
1.367 djm 4765: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4766: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4767: u_int i, value;
1.367 djm 4768: const char *cp;
1.25 markus 4769: char *new_data;
1.367 djm 4770: int r, screen_number;
1.25 markus 4771:
1.367 djm 4772: if (sc->x11_saved_display == NULL)
4773: sc->x11_saved_display = xstrdup(disp);
4774: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4775: error("x11_request_forwarding_with_spoofing: different "
4776: "$DISPLAY already forwarded");
4777: return;
4778: }
4779:
1.266 djm 4780: cp = strchr(disp, ':');
1.25 markus 4781: if (cp)
4782: cp = strchr(cp, '.');
4783: if (cp)
1.245 deraadt 4784: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4785: else
4786: screen_number = 0;
4787:
1.367 djm 4788: if (sc->x11_saved_proto == NULL) {
1.219 djm 4789: /* Save protocol name. */
1.367 djm 4790: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4791:
4792: /* Extract real authentication data. */
1.367 djm 4793: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4794: for (i = 0; i < data_len; i++) {
4795: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4796: fatal("x11_request_forwarding: bad "
4797: "authentication data: %.100s", data);
1.367 djm 4798: sc->x11_saved_data[i] = value;
1.219 djm 4799: }
1.367 djm 4800: sc->x11_saved_data_len = data_len;
1.353 natano 4801:
4802: /* Generate fake data of the same length. */
1.367 djm 4803: sc->x11_fake_data = xmalloc(data_len);
4804: arc4random_buf(sc->x11_fake_data, data_len);
4805: sc->x11_fake_data_len = data_len;
1.25 markus 4806: }
4807:
4808: /* Convert the fake data into hex. */
1.367 djm 4809: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 4810:
4811: /* Send the request packet. */
1.367 djm 4812: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4813: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4814: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4815: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4816: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4817: (r = sshpkt_send(ssh)) != 0 ||
4818: (r = ssh_packet_write_wait(ssh)) != 0)
4819: fatal("%s: send x11-req: %s", __func__, ssh_err(r));
1.321 djm 4820: free(new_data);
1.1 deraadt 4821: }
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