Annotation of src/usr.bin/ssh/channels.c, Revision 1.393
1.393 ! deraadt 1: /* $OpenBSD: channels.c,v 1.392 2019/06/07 14:18:48 dtucker 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);
447: bzero(perm, 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);
1.354 markus 596:
1.384 markus 597: if (log_level_get() >= SYSLOG_LEVEL_DEBUG3) {
598: s = channel_open_message(ssh);
599: debug3("channel %d: status: %s", c->self, s);
600: free(s);
601: }
1.121 markus 602:
1.367 djm 603: channel_close_fds(ssh, c);
604: sshbuf_free(c->input);
605: sshbuf_free(c->output);
606: sshbuf_free(c->extended);
607: c->input = c->output = c->extended = NULL;
1.321 djm 608: free(c->remote_name);
609: c->remote_name = NULL;
610: free(c->path);
611: c->path = NULL;
612: free(c->listening_addr);
613: c->listening_addr = NULL;
1.275 djm 614: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
615: if (cc->abandon_cb != NULL)
1.367 djm 616: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 617: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 618: explicit_bzero(cc, sizeof(*cc));
1.321 djm 619: free(cc);
1.275 djm 620: }
1.280 djm 621: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 622: c->filter_cleanup(ssh, c->self, c->filter_ctx);
623: sc->channels[c->self] = NULL;
1.371 millert 624: explicit_bzero(c, sizeof(*c));
1.321 djm 625: free(c);
1.121 markus 626: }
627:
628: void
1.367 djm 629: channel_free_all(struct ssh *ssh)
1.121 markus 630: {
1.209 avsm 631: u_int i;
1.390 dtucker 632: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 633:
1.390 dtucker 634: for (i = 0; i < sc->channels_alloc; i++)
635: if (sc->channels[i] != NULL)
636: channel_free(ssh, sc->channels[i]);
637:
638: free(sc->channels);
639: sc->channels = NULL;
640: sc->channels_alloc = 0;
641: sc->channel_max_fd = 0;
642:
643: free(sc->x11_saved_display);
644: sc->x11_saved_display = NULL;
645:
646: free(sc->x11_saved_proto);
647: sc->x11_saved_proto = NULL;
648:
649: free(sc->x11_saved_data);
650: sc->x11_saved_data = NULL;
651: sc->x11_saved_data_len = 0;
652:
653: free(sc->x11_fake_data);
654: sc->x11_fake_data = NULL;
655: sc->x11_fake_data_len = 0;
1.131 markus 656: }
657:
1.121 markus 658: /*
659: * Closes the sockets/fds of all channels. This is used to close extra file
660: * descriptors after a fork.
661: */
662: void
1.367 djm 663: channel_close_all(struct ssh *ssh)
1.121 markus 664: {
1.209 avsm 665: u_int i;
1.121 markus 666:
1.367 djm 667: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
668: if (ssh->chanctxt->channels[i] != NULL)
669: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 670: }
671:
672: /*
1.131 markus 673: * Stop listening to channels.
674: */
675: void
1.367 djm 676: channel_stop_listening(struct ssh *ssh)
1.131 markus 677: {
1.209 avsm 678: u_int i;
1.131 markus 679: Channel *c;
680:
1.367 djm 681: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
682: c = ssh->chanctxt->channels[i];
1.131 markus 683: if (c != NULL) {
684: switch (c->type) {
685: case SSH_CHANNEL_AUTH_SOCKET:
686: case SSH_CHANNEL_PORT_LISTENER:
687: case SSH_CHANNEL_RPORT_LISTENER:
688: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 689: case SSH_CHANNEL_UNIX_LISTENER:
690: case SSH_CHANNEL_RUNIX_LISTENER:
1.367 djm 691: channel_close_fd(ssh, &c->sock);
692: channel_free(ssh, c);
1.131 markus 693: break;
694: }
695: }
696: }
697: }
698:
699: /*
1.121 markus 700: * Returns true if no channel has too much buffered data, and false if one or
701: * more channel is overfull.
702: */
703: int
1.367 djm 704: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 705: {
706: u_int i;
1.367 djm 707: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 708: Channel *c;
709:
1.367 djm 710: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
711: c = ssh->chanctxt->channels[i];
712: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
713: continue;
714: if (sshbuf_len(c->output) > maxsize) {
715: debug2("channel %d: big output buffer %zu > %u",
716: c->self, sshbuf_len(c->output), maxsize);
717: return 0;
1.121 markus 718: }
719: }
720: return 1;
721: }
722:
723: /* Returns true if any channel is still open. */
724: int
1.367 djm 725: channel_still_open(struct ssh *ssh)
1.121 markus 726: {
1.209 avsm 727: u_int i;
1.121 markus 728: Channel *c;
729:
1.367 djm 730: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
731: c = ssh->chanctxt->channels[i];
1.121 markus 732: if (c == NULL)
733: continue;
734: switch (c->type) {
735: case SSH_CHANNEL_X11_LISTENER:
736: case SSH_CHANNEL_PORT_LISTENER:
737: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 738: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 739: case SSH_CHANNEL_CLOSED:
740: case SSH_CHANNEL_AUTH_SOCKET:
741: case SSH_CHANNEL_DYNAMIC:
1.372 markus 742: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 743: case SSH_CHANNEL_CONNECTING:
744: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 745: case SSH_CHANNEL_ABANDONED:
1.336 millert 746: case SSH_CHANNEL_UNIX_LISTENER:
747: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 748: continue;
749: case SSH_CHANNEL_LARVAL:
750: continue;
751: case SSH_CHANNEL_OPENING:
752: case SSH_CHANNEL_OPEN:
1.372 markus 753: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 754: case SSH_CHANNEL_X11_OPEN:
1.302 djm 755: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 756: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 757: return 1;
758: default:
1.358 djm 759: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 760: /* NOTREACHED */
761: }
762: }
763: return 0;
764: }
765:
766: /* Returns the id of an open channel suitable for keepaliving */
767: int
1.367 djm 768: channel_find_open(struct ssh *ssh)
1.121 markus 769: {
1.209 avsm 770: u_int i;
1.121 markus 771: Channel *c;
772:
1.367 djm 773: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
774: c = ssh->chanctxt->channels[i];
1.368 djm 775: if (c == NULL || !c->have_remote_id)
1.121 markus 776: continue;
777: switch (c->type) {
778: case SSH_CHANNEL_CLOSED:
779: case SSH_CHANNEL_DYNAMIC:
1.372 markus 780: case SSH_CHANNEL_RDYNAMIC_OPEN:
781: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 782: case SSH_CHANNEL_X11_LISTENER:
783: case SSH_CHANNEL_PORT_LISTENER:
784: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 785: case SSH_CHANNEL_MUX_LISTENER:
786: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 787: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 788: case SSH_CHANNEL_OPENING:
789: case SSH_CHANNEL_CONNECTING:
790: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 791: case SSH_CHANNEL_ABANDONED:
1.336 millert 792: case SSH_CHANNEL_UNIX_LISTENER:
793: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 794: continue;
795: case SSH_CHANNEL_LARVAL:
796: case SSH_CHANNEL_AUTH_SOCKET:
797: case SSH_CHANNEL_OPEN:
798: case SSH_CHANNEL_X11_OPEN:
799: return i;
800: default:
1.358 djm 801: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 802: /* NOTREACHED */
803: }
804: }
805: return -1;
806: }
807:
1.385 djm 808: /* Returns the state of the channel's extended usage flag */
809: const char *
810: channel_format_extended_usage(const Channel *c)
811: {
812: if (c->efd == -1)
813: return "closed";
814:
815: switch (c->extended_usage) {
816: case CHAN_EXTENDED_WRITE:
817: return "write";
818: case CHAN_EXTENDED_READ:
819: return "read";
820: case CHAN_EXTENDED_IGNORE:
821: return "ignore";
822: default:
823: return "UNKNOWN";
824: }
825: }
826:
1.386 djm 827: static char *
828: channel_format_status(const Channel *c)
829: {
830: char *ret = NULL;
831:
832: xasprintf(&ret, "t%d %s%u i%u/%zu o%u/%zu e[%s]/%zu "
833: "fd %d/%d/%d sock %d cc %d",
834: c->type,
835: c->have_remote_id ? "r" : "nr", c->remote_id,
836: c->istate, sshbuf_len(c->input),
837: c->ostate, sshbuf_len(c->output),
838: channel_format_extended_usage(c), sshbuf_len(c->extended),
839: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan);
840: return ret;
841: }
842:
1.121 markus 843: /*
844: * Returns a message describing the currently open forwarded connections,
845: * suitable for sending to the client. The message contains crlf pairs for
846: * newlines.
847: */
848: char *
1.367 djm 849: channel_open_message(struct ssh *ssh)
1.121 markus 850: {
1.367 djm 851: struct sshbuf *buf;
1.121 markus 852: Channel *c;
1.209 avsm 853: u_int i;
1.367 djm 854: int r;
1.386 djm 855: char *cp, *ret;
1.121 markus 856:
1.367 djm 857: if ((buf = sshbuf_new()) == NULL)
858: fatal("%s: sshbuf_new", __func__);
859: if ((r = sshbuf_putf(buf,
860: "The following connections are open:\r\n")) != 0)
861: fatal("%s: sshbuf_putf: %s", __func__, ssh_err(r));
862: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
863: c = ssh->chanctxt->channels[i];
1.121 markus 864: if (c == NULL)
865: continue;
866: switch (c->type) {
867: case SSH_CHANNEL_X11_LISTENER:
868: case SSH_CHANNEL_PORT_LISTENER:
869: case SSH_CHANNEL_RPORT_LISTENER:
870: case SSH_CHANNEL_CLOSED:
871: case SSH_CHANNEL_AUTH_SOCKET:
872: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 873: case SSH_CHANNEL_ABANDONED:
1.302 djm 874: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 875: case SSH_CHANNEL_UNIX_LISTENER:
876: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 877: continue;
878: case SSH_CHANNEL_LARVAL:
879: case SSH_CHANNEL_OPENING:
880: case SSH_CHANNEL_CONNECTING:
881: case SSH_CHANNEL_DYNAMIC:
1.372 markus 882: case SSH_CHANNEL_RDYNAMIC_OPEN:
883: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 884: case SSH_CHANNEL_OPEN:
885: case SSH_CHANNEL_X11_OPEN:
1.354 markus 886: case SSH_CHANNEL_MUX_PROXY:
887: case SSH_CHANNEL_MUX_CLIENT:
1.386 djm 888: cp = channel_format_status(c);
889: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
890: c->self, c->remote_name, cp)) != 0) {
891: free(cp);
1.367 djm 892: fatal("%s: sshbuf_putf: %s",
893: __func__, ssh_err(r));
1.386 djm 894: }
895: free(cp);
1.121 markus 896: continue;
897: default:
1.367 djm 898: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 899: /* NOTREACHED */
900: }
901: }
1.367 djm 902: if ((ret = sshbuf_dup_string(buf)) == NULL)
903: fatal("%s: sshbuf_dup_string", __func__);
904: sshbuf_free(buf);
905: return ret;
906: }
907:
908: static void
909: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
910: {
911: int r;
912:
913: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
914: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
915: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
916: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
917: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
918: fatal("%s: channel %i: open: %s", where, c->self, ssh_err(r));
919: }
1.121 markus 920: }
921:
922: void
1.367 djm 923: channel_send_open(struct ssh *ssh, int id)
1.121 markus 924: {
1.367 djm 925: Channel *c = channel_lookup(ssh, id);
926: int r;
1.180 deraadt 927:
1.121 markus 928: if (c == NULL) {
1.188 itojun 929: logit("channel_send_open: %d: bad id", id);
1.121 markus 930: return;
931: }
1.184 markus 932: debug2("channel %d: send open", id);
1.367 djm 933: open_preamble(ssh, __func__, c, c->ctype);
934: if ((r = sshpkt_send(ssh)) != 0)
935: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.121 markus 936: }
937:
938: void
1.367 djm 939: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 940: {
1.367 djm 941: Channel *c = channel_lookup(ssh, id);
942: int r;
1.180 deraadt 943:
1.121 markus 944: if (c == NULL) {
1.367 djm 945: logit("%s: %d: unknown channel id", __func__, id);
1.121 markus 946: return;
947: }
1.368 djm 948: if (!c->have_remote_id)
949: fatal(":%s: channel %d: no remote id", __func__, c->self);
950:
1.204 djm 951: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 952: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
953: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
954: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
955: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
956: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
957: }
1.121 markus 958: }
1.241 deraadt 959:
1.121 markus 960: void
1.367 djm 961: channel_register_status_confirm(struct ssh *ssh, int id,
962: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 963: {
964: struct channel_confirm *cc;
965: Channel *c;
966:
1.367 djm 967: if ((c = channel_lookup(ssh, id)) == NULL)
968: fatal("%s: %d: bad id", __func__, id);
1.275 djm 969:
1.327 djm 970: cc = xcalloc(1, sizeof(*cc));
1.275 djm 971: cc->cb = cb;
972: cc->abandon_cb = abandon_cb;
973: cc->ctx = ctx;
974: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
975: }
976:
977: void
1.367 djm 978: channel_register_open_confirm(struct ssh *ssh, int id,
979: channel_open_fn *fn, void *ctx)
1.121 markus 980: {
1.367 djm 981: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 982:
1.121 markus 983: if (c == NULL) {
1.367 djm 984: logit("%s: %d: bad id", __func__, id);
1.121 markus 985: return;
986: }
1.275 djm 987: c->open_confirm = fn;
988: c->open_confirm_ctx = ctx;
1.121 markus 989: }
1.241 deraadt 990:
1.121 markus 991: void
1.367 djm 992: channel_register_cleanup(struct ssh *ssh, int id,
993: channel_callback_fn *fn, int do_close)
1.121 markus 994: {
1.367 djm 995: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 996:
1.121 markus 997: if (c == NULL) {
1.367 djm 998: logit("%s: %d: bad id", __func__, id);
1.121 markus 999: return;
1000: }
1.131 markus 1001: c->detach_user = fn;
1.225 djm 1002: c->detach_close = do_close;
1.121 markus 1003: }
1.241 deraadt 1004:
1.121 markus 1005: void
1.367 djm 1006: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 1007: {
1.367 djm 1008: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1009:
1.121 markus 1010: if (c == NULL) {
1.367 djm 1011: logit("%s: %d: bad id", __func__, id);
1.121 markus 1012: return;
1.52 markus 1013: }
1.131 markus 1014: c->detach_user = NULL;
1.225 djm 1015: c->detach_close = 0;
1.121 markus 1016: }
1.241 deraadt 1017:
1.121 markus 1018: void
1.367 djm 1019: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1020: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1021: {
1.367 djm 1022: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1023:
1.121 markus 1024: if (c == NULL) {
1.367 djm 1025: logit("%s: %d: bad id", __func__, id);
1.121 markus 1026: return;
1.52 markus 1027: }
1.231 reyk 1028: c->input_filter = ifn;
1029: c->output_filter = ofn;
1.279 djm 1030: c->filter_ctx = ctx;
1.280 djm 1031: c->filter_cleanup = cfn;
1.52 markus 1032: }
1033:
1.49 markus 1034: void
1.367 djm 1035: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1036: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1037: {
1.367 djm 1038: Channel *c = channel_lookup(ssh, id);
1039: int r;
1.180 deraadt 1040:
1.121 markus 1041: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1042: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1043: if (!c->have_remote_id)
1044: fatal(":%s: channel %d: no remote id", __func__, c->self);
1045:
1.367 djm 1046: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1047: c->type = SSH_CHANNEL_OPEN;
1.168 markus 1048: c->local_window = c->local_window_max = window_max;
1.367 djm 1049:
1050: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1051: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1052: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1053: (r = sshpkt_send(ssh)) != 0)
1054: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.1 deraadt 1055: }
1056:
1.127 itojun 1057: static void
1.367 djm 1058: channel_pre_listener(struct ssh *ssh, Channel *c,
1059: fd_set *readset, fd_set *writeset)
1.41 markus 1060: {
1061: FD_SET(c->sock, readset);
1062: }
1063:
1.127 itojun 1064: static void
1.367 djm 1065: channel_pre_connecting(struct ssh *ssh, Channel *c,
1066: fd_set *readset, fd_set *writeset)
1.75 markus 1067: {
1068: debug3("channel %d: waiting for connection", c->self);
1069: FD_SET(c->sock, writeset);
1070: }
1071:
1.127 itojun 1072: static void
1.367 djm 1073: channel_pre_open(struct ssh *ssh, Channel *c,
1074: fd_set *readset, fd_set *writeset)
1.41 markus 1075: {
1.44 markus 1076: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1077: c->remote_window > 0 &&
1.367 djm 1078: sshbuf_len(c->input) < c->remote_window &&
1079: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.44 markus 1080: FD_SET(c->rfd, readset);
1081: if (c->ostate == CHAN_OUTPUT_OPEN ||
1082: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1083: if (sshbuf_len(c->output) > 0) {
1.44 markus 1084: FD_SET(c->wfd, writeset);
1085: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1086: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1087: debug2("channel %d: "
1088: "obuf_empty delayed efd %d/(%zu)", c->self,
1089: c->efd, sshbuf_len(c->extended));
1.172 markus 1090: else
1.367 djm 1091: chan_obuf_empty(ssh, c);
1.44 markus 1092: }
1093: }
1094: /** XXX check close conditions, too */
1.358 djm 1095: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1096: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1097: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1098: sshbuf_len(c->extended) > 0)
1.44 markus 1099: FD_SET(c->efd, writeset);
1.306 djm 1100: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1101: (c->extended_usage == CHAN_EXTENDED_READ ||
1102: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1103: sshbuf_len(c->extended) < c->remote_window)
1.44 markus 1104: FD_SET(c->efd, readset);
1105: }
1.204 djm 1106: /* XXX: What about efd? races? */
1.44 markus 1107: }
1108:
1.41 markus 1109: /*
1110: * This is a special state for X11 authentication spoofing. An opened X11
1111: * connection (when authentication spoofing is being done) remains in this
1112: * state until the first packet has been completely read. The authentication
1113: * data in that packet is then substituted by the real data if it matches the
1114: * fake data, and the channel is put into normal mode.
1.51 markus 1115: * XXX All this happens at the client side.
1.121 markus 1116: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1117: */
1.127 itojun 1118: static int
1.367 djm 1119: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1120: {
1.367 djm 1121: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1122: u_char *ucp;
1123: u_int proto_len, data_len;
1.25 markus 1124:
1.347 djm 1125: /* Is this being called after the refusal deadline? */
1.367 djm 1126: if (sc->x11_refuse_time != 0 &&
1127: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1128: verbose("Rejected X11 connection after ForwardX11Timeout "
1129: "expired");
1130: return -1;
1131: }
1132:
1.41 markus 1133: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1134: if (sshbuf_len(b) < 12)
1.41 markus 1135: return 0;
1136:
1137: /* Parse the lengths of variable-length fields. */
1.367 djm 1138: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1139: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1140: proto_len = 256 * ucp[6] + ucp[7];
1141: data_len = 256 * ucp[8] + ucp[9];
1142: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1143: proto_len = ucp[6] + 256 * ucp[7];
1144: data_len = ucp[8] + 256 * ucp[9];
1145: } else {
1.194 markus 1146: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1147: ucp[0]);
1.41 markus 1148: return -1;
1149: }
1150:
1151: /* Check if the whole packet is in buffer. */
1.367 djm 1152: if (sshbuf_len(b) <
1.41 markus 1153: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1154: return 0;
1155:
1156: /* Check if authentication protocol matches. */
1.367 djm 1157: if (proto_len != strlen(sc->x11_saved_proto) ||
1158: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1159: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1160: return -1;
1161: }
1162: /* Check if authentication data matches our fake data. */
1.367 djm 1163: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1164: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1165: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1166: debug2("X11 auth data does not match fake data.");
1.41 markus 1167: return -1;
1168: }
1169: /* Check fake data length */
1.367 djm 1170: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1171: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1172: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1173: return -1;
1174: }
1175: /*
1176: * Received authentication protocol and data match
1177: * our fake data. Substitute the fake data with real
1178: * data.
1179: */
1180: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1181: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1182: return 1;
1183: }
1184:
1.127 itojun 1185: static void
1.367 djm 1186: channel_pre_x11_open(struct ssh *ssh, Channel *c,
1187: fd_set *readset, fd_set *writeset)
1.41 markus 1188: {
1.367 djm 1189: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1190:
1191: /* c->force_drain = 1; */
1192:
1.41 markus 1193: if (ret == 1) {
1194: c->type = SSH_CHANNEL_OPEN;
1.367 djm 1195: channel_pre_open(ssh, c, readset, writeset);
1.41 markus 1196: } else if (ret == -1) {
1.188 itojun 1197: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1198: debug2("X11 rejected %d i%d/o%d",
1199: c->self, c->istate, c->ostate);
1200: chan_read_failed(ssh, c);
1201: sshbuf_reset(c->input);
1202: chan_ibuf_empty(ssh, c);
1203: sshbuf_reset(c->output);
1204: chan_write_failed(ssh, c);
1.194 markus 1205: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1206: }
1207: }
1.25 markus 1208:
1.302 djm 1209: static void
1.367 djm 1210: channel_pre_mux_client(struct ssh *ssh,
1211: Channel *c, fd_set *readset, fd_set *writeset)
1.302 djm 1212: {
1.304 djm 1213: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1214: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.302 djm 1215: FD_SET(c->rfd, readset);
1216: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1217: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1218: sshbuf_reset(c->input);
1219: chan_ibuf_empty(ssh, c);
1.302 djm 1220: /* Start output drain. XXX just kill chan? */
1.367 djm 1221: chan_rcvd_oclose(ssh, c);
1.302 djm 1222: }
1223: if (c->ostate == CHAN_OUTPUT_OPEN ||
1224: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1225: if (sshbuf_len(c->output) > 0)
1.302 djm 1226: FD_SET(c->wfd, writeset);
1227: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1228: chan_obuf_empty(ssh, c);
1.302 djm 1229: }
1230: }
1231:
1.104 markus 1232: /* try to decode a socks4 header */
1.127 itojun 1233: static int
1.372 markus 1234: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1235: {
1.367 djm 1236: const u_char *p;
1237: char *host;
1.292 djm 1238: u_int len, have, i, found, need;
1.148 deraadt 1239: char username[256];
1.103 markus 1240: struct {
1241: u_int8_t version;
1242: u_int8_t command;
1243: u_int16_t dest_port;
1.104 markus 1244: struct in_addr dest_addr;
1.103 markus 1245: } s4_req, s4_rsp;
1.367 djm 1246: int r;
1.103 markus 1247:
1.104 markus 1248: debug2("channel %d: decode socks4", c->self);
1.109 markus 1249:
1.372 markus 1250: have = sshbuf_len(input);
1.109 markus 1251: len = sizeof(s4_req);
1252: if (have < len)
1253: return 0;
1.372 markus 1254: p = sshbuf_ptr(input);
1.292 djm 1255:
1256: need = 1;
1257: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1258: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1259: debug2("channel %d: socks4a request", c->self);
1260: /* ... and needs an extra string (the hostname) */
1261: need = 2;
1262: }
1263: /* Check for terminating NUL on the string(s) */
1.109 markus 1264: for (found = 0, i = len; i < have; i++) {
1265: if (p[i] == '\0') {
1.292 djm 1266: found++;
1267: if (found == need)
1268: break;
1.109 markus 1269: }
1270: if (i > 1024) {
1271: /* the peer is probably sending garbage */
1272: debug("channel %d: decode socks4: too long",
1273: c->self);
1274: return -1;
1275: }
1276: }
1.292 djm 1277: if (found < need)
1.109 markus 1278: return 0;
1.372 markus 1279: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1280: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1281: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1282: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.367 djm 1283: debug("channels %d: decode socks4: %s", c->self, ssh_err(r));
1284: return -1;
1285: }
1.372 markus 1286: have = sshbuf_len(input);
1287: p = sshbuf_ptr(input);
1.364 djm 1288: if (memchr(p, '\0', have) == NULL) {
1289: error("channel %d: decode socks4: user not nul terminated",
1.331 djm 1290: c->self);
1.364 djm 1291: return -1;
1292: }
1.103 markus 1293: len = strlen(p);
1.106 markus 1294: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1295: len++; /* trailing '\0' */
1.103 markus 1296: strlcpy(username, p, sizeof(username));
1.372 markus 1297: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1298: fatal("%s: channel %d: consume: %s", __func__,
1299: c->self, ssh_err(r));
1300: }
1.321 djm 1301: free(c->path);
1302: c->path = NULL;
1.292 djm 1303: if (need == 1) { /* SOCKS4: one string */
1304: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1305: c->path = xstrdup(host);
1.292 djm 1306: } else { /* SOCKS4A: two strings */
1.372 markus 1307: have = sshbuf_len(input);
1308: p = sshbuf_ptr(input);
1.364 djm 1309: if (memchr(p, '\0', have) == NULL) {
1310: error("channel %d: decode socks4a: host not nul "
1311: "terminated", c->self);
1312: return -1;
1313: }
1.292 djm 1314: len = strlen(p);
1315: debug2("channel %d: decode socks4a: host %s/%d",
1316: c->self, p, len);
1317: len++; /* trailing '\0' */
1.293 djm 1318: if (len > NI_MAXHOST) {
1.292 djm 1319: error("channel %d: hostname \"%.100s\" too long",
1320: c->self, p);
1321: return -1;
1322: }
1.293 djm 1323: c->path = xstrdup(p);
1.372 markus 1324: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1325: fatal("%s: channel %d: consume: %s", __func__,
1326: c->self, ssh_err(r));
1327: }
1.292 djm 1328: }
1.103 markus 1329: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1330:
1.194 markus 1331: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1332: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1333:
1.104 markus 1334: if (s4_req.command != 1) {
1.292 djm 1335: debug("channel %d: cannot handle: %s cn %d",
1336: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1337: return -1;
1.103 markus 1338: }
1.104 markus 1339: s4_rsp.version = 0; /* vn: 0 for reply */
1340: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1341: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1342: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.372 markus 1343: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0) {
1.367 djm 1344: fatal("%s: channel %d: append reply: %s", __func__,
1345: c->self, ssh_err(r));
1346: }
1.104 markus 1347: return 1;
1348: }
1349:
1.193 markus 1350: /* try to decode a socks5 header */
1351: #define SSH_SOCKS5_AUTHDONE 0x1000
1352: #define SSH_SOCKS5_NOAUTH 0x00
1353: #define SSH_SOCKS5_IPV4 0x01
1354: #define SSH_SOCKS5_DOMAIN 0x03
1355: #define SSH_SOCKS5_IPV6 0x04
1356: #define SSH_SOCKS5_CONNECT 0x01
1357: #define SSH_SOCKS5_SUCCESS 0x00
1358:
1359: static int
1.372 markus 1360: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1361: {
1.367 djm 1362: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1363: struct {
1364: u_int8_t version;
1365: u_int8_t command;
1366: u_int8_t reserved;
1367: u_int8_t atyp;
1368: } s5_req, s5_rsp;
1369: u_int16_t dest_port;
1.324 djm 1370: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1371: const u_char *p;
1.252 djm 1372: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1373: int r;
1.193 markus 1374:
1375: debug2("channel %d: decode socks5", c->self);
1.372 markus 1376: p = sshbuf_ptr(input);
1.193 markus 1377: if (p[0] != 0x05)
1378: return -1;
1.372 markus 1379: have = sshbuf_len(input);
1.193 markus 1380: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1381: /* format: ver | nmethods | methods */
1.198 djm 1382: if (have < 2)
1.193 markus 1383: return 0;
1384: nmethods = p[1];
1385: if (have < nmethods + 2)
1386: return 0;
1387: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1388: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1389: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1390: found = 1;
1391: break;
1392: }
1393: }
1394: if (!found) {
1395: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1396: c->self);
1397: return -1;
1398: }
1.372 markus 1399: if ((r = sshbuf_consume(input, nmethods + 2)) != 0) {
1.367 djm 1400: fatal("%s: channel %d: consume: %s", __func__,
1401: c->self, ssh_err(r));
1402: }
1403: /* version, method */
1.372 markus 1404: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1405: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0) {
1.367 djm 1406: fatal("%s: channel %d: append reply: %s", __func__,
1407: c->self, ssh_err(r));
1408: }
1.193 markus 1409: c->flags |= SSH_SOCKS5_AUTHDONE;
1410: debug2("channel %d: socks5 auth done", c->self);
1411: return 0; /* need more */
1412: }
1413: debug2("channel %d: socks5 post auth", c->self);
1414: if (have < sizeof(s5_req)+1)
1415: return 0; /* need more */
1.247 deraadt 1416: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1417: if (s5_req.version != 0x05 ||
1418: s5_req.command != SSH_SOCKS5_CONNECT ||
1419: s5_req.reserved != 0x00) {
1.194 markus 1420: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1421: return -1;
1422: }
1.213 deraadt 1423: switch (s5_req.atyp){
1.193 markus 1424: case SSH_SOCKS5_IPV4:
1425: addrlen = 4;
1426: af = AF_INET;
1427: break;
1428: case SSH_SOCKS5_DOMAIN:
1429: addrlen = p[sizeof(s5_req)];
1430: af = -1;
1431: break;
1432: case SSH_SOCKS5_IPV6:
1433: addrlen = 16;
1434: af = AF_INET6;
1435: break;
1436: default:
1.194 markus 1437: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1438: return -1;
1439: }
1.252 djm 1440: need = sizeof(s5_req) + addrlen + 2;
1441: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1442: need++;
1443: if (have < need)
1.193 markus 1444: return 0;
1.372 markus 1445: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0) {
1.367 djm 1446: fatal("%s: channel %d: consume: %s", __func__,
1447: c->self, ssh_err(r));
1448: }
1449: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1450: /* host string length */
1.372 markus 1451: if ((r = sshbuf_consume(input, 1)) != 0) {
1.367 djm 1452: fatal("%s: channel %d: consume: %s", __func__,
1453: c->self, ssh_err(r));
1454: }
1455: }
1.372 markus 1456: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1457: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.367 djm 1458: debug("channel %d: parse addr/port: %s", c->self, ssh_err(r));
1459: return -1;
1460: }
1.193 markus 1461: dest_addr[addrlen] = '\0';
1.321 djm 1462: free(c->path);
1463: c->path = NULL;
1.293 djm 1464: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1465: if (addrlen >= NI_MAXHOST) {
1.293 djm 1466: error("channel %d: dynamic request: socks5 hostname "
1467: "\"%.100s\" too long", c->self, dest_addr);
1468: return -1;
1469: }
1470: c->path = xstrdup(dest_addr);
1471: } else {
1472: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1473: return -1;
1474: c->path = xstrdup(ntop);
1475: }
1.193 markus 1476: c->host_port = ntohs(dest_port);
1.198 djm 1477:
1.194 markus 1478: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1479: c->self, c->path, c->host_port, s5_req.command);
1480:
1481: s5_rsp.version = 0x05;
1482: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1483: s5_rsp.reserved = 0; /* ignored */
1484: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1485: dest_port = 0; /* ignored */
1486:
1.372 markus 1487: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1488: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1489: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.367 djm 1490: fatal("%s: channel %d: append reply: %s", __func__,
1491: c->self, ssh_err(r));
1.193 markus 1492: return 1;
1.301 dtucker 1493: }
1494:
1495: Channel *
1.367 djm 1496: channel_connect_stdio_fwd(struct ssh *ssh,
1497: const char *host_to_connect, u_short port_to_connect, int in, int out)
1.301 dtucker 1498: {
1499: Channel *c;
1500:
1.367 djm 1501: debug("%s %s:%d", __func__, host_to_connect, port_to_connect);
1.301 dtucker 1502:
1.367 djm 1503: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1504: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1505: 0, "stdio-forward", /*nonblock*/0);
1506:
1507: c->path = xstrdup(host_to_connect);
1508: c->host_port = port_to_connect;
1509: c->listening_port = 0;
1510: c->force_drain = 1;
1511:
1.367 djm 1512: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1513: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1514:
1515: return c;
1.193 markus 1516: }
1517:
1.104 markus 1518: /* dynamic port forwarding */
1.127 itojun 1519: static void
1.367 djm 1520: channel_pre_dynamic(struct ssh *ssh, Channel *c,
1521: fd_set *readset, fd_set *writeset)
1.104 markus 1522: {
1.367 djm 1523: const u_char *p;
1.217 djm 1524: u_int have;
1525: int ret;
1.103 markus 1526:
1.367 djm 1527: have = sshbuf_len(c->input);
1.104 markus 1528: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1529: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1530: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1531: if (have < 3) {
1.104 markus 1532: /* need more */
1533: FD_SET(c->sock, readset);
1534: return;
1535: }
1536: /* try to guess the protocol */
1.367 djm 1537: p = sshbuf_ptr(c->input);
1538: /* XXX sshbuf_peek_u8? */
1.104 markus 1539: switch (p[0]) {
1540: case 0x04:
1.372 markus 1541: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1542: break;
1543: case 0x05:
1.372 markus 1544: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1545: break;
1546: default:
1547: ret = -1;
1548: break;
1549: }
1550: if (ret < 0) {
1.367 djm 1551: chan_mark_dead(ssh, c);
1.104 markus 1552: } else if (ret == 0) {
1553: debug2("channel %d: pre_dynamic: need more", c->self);
1554: /* need more */
1555: FD_SET(c->sock, readset);
1.372 markus 1556: if (sshbuf_len(c->output))
1557: FD_SET(c->sock, writeset);
1.104 markus 1558: } else {
1559: /* switch to the next state */
1560: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1561: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1562: }
1.103 markus 1563: }
1564:
1.372 markus 1565: /* simulate read-error */
1566: static void
1567: rdynamic_close(struct ssh *ssh, Channel *c)
1568: {
1569: c->type = SSH_CHANNEL_OPEN;
1570: chan_read_failed(ssh, c);
1571: sshbuf_reset(c->input);
1572: chan_ibuf_empty(ssh, c);
1573: sshbuf_reset(c->output);
1574: chan_write_failed(ssh, c);
1575: }
1576:
1577: /* reverse dynamic port forwarding */
1578: static void
1579: channel_before_prepare_select_rdynamic(struct ssh *ssh, Channel *c)
1580: {
1581: const u_char *p;
1582: u_int have, len;
1583: int r, ret;
1584:
1585: have = sshbuf_len(c->output);
1586: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1587: /* sshbuf_dump(c->output, stderr); */
1588: /* EOF received */
1589: if (c->flags & CHAN_EOF_RCVD) {
1590: if ((r = sshbuf_consume(c->output, have)) != 0) {
1591: fatal("%s: channel %d: consume: %s",
1592: __func__, c->self, ssh_err(r));
1593: }
1594: rdynamic_close(ssh, c);
1595: return;
1596: }
1597: /* check if the fixed size part of the packet is in buffer. */
1598: if (have < 3)
1599: return;
1600: /* try to guess the protocol */
1601: p = sshbuf_ptr(c->output);
1602: switch (p[0]) {
1603: case 0x04:
1604: /* switch input/output for reverse forwarding */
1605: ret = channel_decode_socks4(c, c->output, c->input);
1606: break;
1607: case 0x05:
1608: ret = channel_decode_socks5(c, c->output, c->input);
1609: break;
1610: default:
1611: ret = -1;
1612: break;
1613: }
1614: if (ret < 0) {
1615: rdynamic_close(ssh, c);
1616: } else if (ret == 0) {
1617: debug2("channel %d: pre_rdynamic: need more", c->self);
1618: /* send socks request to peer */
1619: len = sshbuf_len(c->input);
1620: if (len > 0 && len < c->remote_window) {
1621: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1622: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1623: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1624: (r = sshpkt_send(ssh)) != 0) {
1625: fatal("%s: channel %i: rdynamic: %s", __func__,
1626: c->self, ssh_err(r));
1627: }
1628: if ((r = sshbuf_consume(c->input, len)) != 0) {
1629: fatal("%s: channel %d: consume: %s",
1630: __func__, c->self, ssh_err(r));
1631: }
1632: c->remote_window -= len;
1633: }
1634: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1635: /* the connect failed */
1636: rdynamic_close(ssh, c);
1637: }
1638: }
1639:
1.41 markus 1640: /* This is our fake X11 server socket. */
1.127 itojun 1641: static void
1.367 djm 1642: channel_post_x11_listener(struct ssh *ssh, Channel *c,
1643: fd_set *readset, fd_set *writeset)
1.41 markus 1644: {
1.113 markus 1645: Channel *nc;
1.285 djm 1646: struct sockaddr_storage addr;
1.367 djm 1647: int r, newsock, oerrno, remote_port;
1.41 markus 1648: socklen_t addrlen;
1.85 markus 1649: char buf[16384], *remote_ipaddr;
1.25 markus 1650:
1.367 djm 1651: if (!FD_ISSET(c->sock, readset))
1652: return;
1653:
1654: debug("X11 connection requested.");
1655: addrlen = sizeof(addr);
1656: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1657: if (c->single_connection) {
1658: oerrno = errno;
1659: debug2("single_connection: closing X11 listener.");
1660: channel_close_fd(ssh, &c->sock);
1661: chan_mark_dead(ssh, c);
1662: errno = oerrno;
1663: }
1.393 ! deraadt 1664: if (newsock == -1) {
1.367 djm 1665: if (errno != EINTR && errno != EWOULDBLOCK &&
1666: errno != ECONNABORTED)
1667: error("accept: %.100s", strerror(errno));
1668: if (errno == EMFILE || errno == ENFILE)
1669: c->notbefore = monotime() + 1;
1670: return;
1671: }
1672: set_nodelay(newsock);
1673: remote_ipaddr = get_peer_ipaddr(newsock);
1674: remote_port = get_peer_port(newsock);
1675: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1676: remote_ipaddr, remote_port);
1677:
1678: nc = channel_new(ssh, "accepted x11 socket",
1679: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1680: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1681: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1682: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1683: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.367 djm 1684: fatal("%s: channel %i: reply %s", __func__,
1685: c->self, ssh_err(r));
1.41 markus 1686: }
1.367 djm 1687: if ((r = sshpkt_send(ssh)) != 0)
1688: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1689: free(remote_ipaddr);
1.41 markus 1690: }
1.25 markus 1691:
1.127 itojun 1692: static void
1.367 djm 1693: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1694: {
1.328 djm 1695: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1696: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1697: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1698: int remote_port = get_peer_port(c->sock);
1.367 djm 1699: int r;
1.303 djm 1700:
1701: if (remote_port == -1) {
1702: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1703: free(remote_ipaddr);
1.303 djm 1704: remote_ipaddr = xstrdup("127.0.0.1");
1705: remote_port = 65535;
1706: }
1.103 markus 1707:
1.367 djm 1708: free(c->remote_name);
1709: xasprintf(&c->remote_name,
1.103 markus 1710: "%s: listening port %d for %.100s port %d, "
1.328 djm 1711: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1712: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1713: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1714:
1.367 djm 1715: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1716: if (strcmp(rtype, "direct-tcpip") == 0) {
1717: /* target host, port */
1.367 djm 1718: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1719: (r = sshpkt_put_u32(ssh, c->host_port)) != 0) {
1720: fatal("%s: channel %i: reply %s", __func__,
1721: c->self, ssh_err(r));
1722: }
1.358 djm 1723: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1724: /* target path */
1.367 djm 1725: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1726: fatal("%s: channel %i: reply %s", __func__,
1727: c->self, ssh_err(r));
1728: }
1.358 djm 1729: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1730: /* listen path */
1.367 djm 1731: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1732: fatal("%s: channel %i: reply %s", __func__,
1733: c->self, ssh_err(r));
1734: }
1.103 markus 1735: } else {
1.358 djm 1736: /* listen address, port */
1.367 djm 1737: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1738: (r = sshpkt_put_u32(ssh, local_port)) != 0) {
1739: fatal("%s: channel %i: reply %s", __func__,
1740: c->self, ssh_err(r));
1741: }
1.358 djm 1742: }
1743: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1744: /* reserved for future owner/mode info */
1.367 djm 1745: if ((r = sshpkt_put_cstring(ssh, "")) != 0) {
1746: fatal("%s: channel %i: reply %s", __func__,
1747: c->self, ssh_err(r));
1748: }
1.358 djm 1749: } else {
1750: /* originator host and port */
1.367 djm 1751: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1752: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0) {
1753: fatal("%s: channel %i: reply %s", __func__,
1754: c->self, ssh_err(r));
1755: }
1.103 markus 1756: }
1.367 djm 1757: if ((r = sshpkt_send(ssh)) != 0)
1758: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1.321 djm 1759: free(remote_ipaddr);
1.328 djm 1760: free(local_ipaddr);
1.103 markus 1761: }
1762:
1.347 djm 1763: void
1.367 djm 1764: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1765: {
1.367 djm 1766: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1767: }
1768:
1.41 markus 1769: /*
1770: * This socket is listening for connections to a forwarded TCP/IP port.
1771: */
1.127 itojun 1772: static void
1.367 djm 1773: channel_post_port_listener(struct ssh *ssh, Channel *c,
1774: fd_set *readset, fd_set *writeset)
1.41 markus 1775: {
1.103 markus 1776: Channel *nc;
1.285 djm 1777: struct sockaddr_storage addr;
1.113 markus 1778: int newsock, nextstate;
1.41 markus 1779: socklen_t addrlen;
1.103 markus 1780: char *rtype;
1.73 markus 1781:
1.367 djm 1782: if (!FD_ISSET(c->sock, readset))
1783: return;
1784:
1785: debug("Connection to port %d forwarding to %.100s port %d requested.",
1786: c->listening_port, c->path, c->host_port);
1.103 markus 1787:
1.367 djm 1788: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1789: nextstate = SSH_CHANNEL_OPENING;
1790: rtype = "forwarded-tcpip";
1791: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1792: nextstate = SSH_CHANNEL_OPENING;
1793: rtype = "forwarded-streamlocal@openssh.com";
1794: } else if (c->host_port == PORT_STREAMLOCAL) {
1795: nextstate = SSH_CHANNEL_OPENING;
1796: rtype = "direct-streamlocal@openssh.com";
1797: } else if (c->host_port == 0) {
1798: nextstate = SSH_CHANNEL_DYNAMIC;
1799: rtype = "dynamic-tcpip";
1800: } else {
1801: nextstate = SSH_CHANNEL_OPENING;
1802: rtype = "direct-tcpip";
1803: }
1.103 markus 1804:
1.367 djm 1805: addrlen = sizeof(addr);
1806: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 ! deraadt 1807: if (newsock == -1) {
1.367 djm 1808: if (errno != EINTR && errno != EWOULDBLOCK &&
1809: errno != ECONNABORTED)
1810: error("accept: %.100s", strerror(errno));
1811: if (errno == EMFILE || errno == ENFILE)
1812: c->notbefore = monotime() + 1;
1813: return;
1.41 markus 1814: }
1.367 djm 1815: if (c->host_port != PORT_STREAMLOCAL)
1816: set_nodelay(newsock);
1817: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1818: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1819: nc->listening_port = c->listening_port;
1820: nc->host_port = c->host_port;
1821: if (c->path != NULL)
1822: nc->path = xstrdup(c->path);
1823:
1824: if (nextstate != SSH_CHANNEL_DYNAMIC)
1825: port_open_helper(ssh, nc, rtype);
1.41 markus 1826: }
1.25 markus 1827:
1.41 markus 1828: /*
1829: * This is the authentication agent socket listening for connections from
1830: * clients.
1831: */
1.127 itojun 1832: static void
1.367 djm 1833: channel_post_auth_listener(struct ssh *ssh, Channel *c,
1834: fd_set *readset, fd_set *writeset)
1.41 markus 1835: {
1.113 markus 1836: Channel *nc;
1.367 djm 1837: int r, newsock;
1.285 djm 1838: struct sockaddr_storage addr;
1.41 markus 1839: socklen_t addrlen;
1.25 markus 1840:
1.367 djm 1841: if (!FD_ISSET(c->sock, readset))
1842: return;
1843:
1844: addrlen = sizeof(addr);
1845: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 ! deraadt 1846: if (newsock == -1) {
1.367 djm 1847: error("accept from auth socket: %.100s", strerror(errno));
1848: if (errno == EMFILE || errno == ENFILE)
1849: c->notbefore = monotime() + 1;
1850: return;
1.41 markus 1851: }
1.367 djm 1852: nc = channel_new(ssh, "accepted auth socket",
1853: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1854: c->local_window_max, c->local_maxpacket,
1855: 0, "accepted auth socket", 1);
1856: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1857: if ((r = sshpkt_send(ssh)) != 0)
1858: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.41 markus 1859: }
1.25 markus 1860:
1.127 itojun 1861: static void
1.367 djm 1862: channel_post_connecting(struct ssh *ssh, Channel *c,
1863: fd_set *readset, fd_set *writeset)
1.75 markus 1864: {
1.372 markus 1865: int err = 0, sock, isopen, r;
1.129 stevesk 1866: socklen_t sz = sizeof(err);
1.114 markus 1867:
1.367 djm 1868: if (!FD_ISSET(c->sock, writeset))
1869: return;
1.368 djm 1870: if (!c->have_remote_id)
1871: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.372 markus 1872: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1873: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.393 ! deraadt 1874: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 1875: err = errno;
1876: error("getsockopt SO_ERROR failed");
1877: }
1878: if (err == 0) {
1879: debug("channel %d: connected to %s port %d",
1880: c->self, c->connect_ctx.host, c->connect_ctx.port);
1881: channel_connect_ctx_free(&c->connect_ctx);
1882: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1883: if (isopen) {
1884: /* no message necessary */
1885: } else {
1886: if ((r = sshpkt_start(ssh,
1887: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1888: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1889: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1890: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1891: (r = sshpkt_put_u32(ssh, c->local_maxpacket))
1892: != 0)
1893: fatal("%s: channel %i: confirm: %s", __func__,
1894: c->self, ssh_err(r));
1895: if ((r = sshpkt_send(ssh)) != 0)
1896: fatal("%s: channel %i: %s", __func__, c->self,
1897: ssh_err(r));
1.367 djm 1898: }
1899: } else {
1900: debug("channel %d: connection failed: %s",
1901: c->self, strerror(err));
1902: /* Try next address, if any */
1903: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1904: close(c->sock);
1905: c->sock = c->rfd = c->wfd = sock;
1906: channel_find_maxfd(ssh->chanctxt);
1907: return;
1908: }
1909: /* Exhausted all addresses */
1910: error("connect_to %.100s port %d: failed.",
1911: c->connect_ctx.host, c->connect_ctx.port);
1912: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1913: if (isopen) {
1914: rdynamic_close(ssh, c);
1915: } else {
1916: if ((r = sshpkt_start(ssh,
1917: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1918: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 1919: (r = sshpkt_put_u32(ssh,
1920: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
1921: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1922: (r = sshpkt_put_cstring(ssh, "")) != 0) {
1.372 markus 1923: fatal("%s: channel %i: failure: %s", __func__,
1924: c->self, ssh_err(r));
1.378 djm 1925: }
1.372 markus 1926: if ((r = sshpkt_send(ssh)) != 0)
1927: fatal("%s: channel %i: %s", __func__, c->self,
1928: ssh_err(r));
1929: chan_mark_dead(ssh, c);
1.75 markus 1930: }
1931: }
1932: }
1933:
1.127 itojun 1934: static int
1.367 djm 1935: channel_handle_rfd(struct ssh *ssh, Channel *c,
1936: fd_set *readset, fd_set *writeset)
1.41 markus 1937: {
1.214 markus 1938: char buf[CHAN_RBUF];
1.367 djm 1939: ssize_t len;
1940: int r;
1.25 markus 1941:
1.367 djm 1942: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
1943: return 1;
1944:
1945: len = read(c->rfd, buf, sizeof(buf));
1.393 ! deraadt 1946: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 1947: return 1;
1948: if (len <= 0) {
1949: debug2("channel %d: read<=0 rfd %d len %zd",
1950: c->self, c->rfd, len);
1951: if (c->type != SSH_CHANNEL_OPEN) {
1952: debug2("channel %d: not open", c->self);
1953: chan_mark_dead(ssh, c);
1.41 markus 1954: return -1;
1.65 markus 1955: } else {
1.367 djm 1956: chan_read_failed(ssh, c);
1.65 markus 1957: }
1.367 djm 1958: return -1;
1959: }
1960: if (c->input_filter != NULL) {
1961: if (c->input_filter(ssh, c, buf, len) == -1) {
1962: debug2("channel %d: filter stops", c->self);
1963: chan_read_failed(ssh, c);
1964: }
1965: } else if (c->datagram) {
1966: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1967: fatal("%s: channel %d: put datagram: %s", __func__,
1968: c->self, ssh_err(r));
1969: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
1970: fatal("%s: channel %d: put data: %s", __func__,
1971: c->self, ssh_err(r));
1.41 markus 1972: }
1973: return 1;
1974: }
1.241 deraadt 1975:
1.127 itojun 1976: static int
1.367 djm 1977: channel_handle_wfd(struct ssh *ssh, Channel *c,
1978: fd_set *readset, fd_set *writeset)
1.41 markus 1979: {
1.95 markus 1980: struct termios tio;
1.367 djm 1981: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1982: size_t dlen, olen = 0;
1983: int r, len;
1984:
1985: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
1986: sshbuf_len(c->output) == 0)
1987: return 1;
1.25 markus 1988:
1.41 markus 1989: /* Send buffered output data to the socket. */
1.367 djm 1990: olen = sshbuf_len(c->output);
1991: if (c->output_filter != NULL) {
1992: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1993: debug2("channel %d: filter stops", c->self);
1994: if (c->type != SSH_CHANNEL_OPEN)
1995: chan_mark_dead(ssh, c);
1996: else
1997: chan_write_failed(ssh, c);
1998: return -1;
1.231 reyk 1999: }
1.367 djm 2000: } else if (c->datagram) {
2001: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
2002: fatal("%s: channel %d: get datagram: %s", __func__,
2003: c->self, ssh_err(r));
1.369 djm 2004: buf = data;
1.367 djm 2005: } else {
2006: buf = data = sshbuf_mutable_ptr(c->output);
2007: dlen = sshbuf_len(c->output);
2008: }
1.231 reyk 2009:
1.367 djm 2010: if (c->datagram) {
2011: /* ignore truncated writes, datagrams might get lost */
1.374 djm 2012: len = write(c->wfd, buf, dlen);
1.367 djm 2013: free(data);
1.393 ! deraadt 2014: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 2015: return 1;
1.367 djm 2016: if (len <= 0)
2017: goto write_fail;
2018: goto out;
2019: }
2020:
2021: len = write(c->wfd, buf, dlen);
1.393 ! deraadt 2022: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2023: return 1;
2024: if (len <= 0) {
2025: write_fail:
2026: if (c->type != SSH_CHANNEL_OPEN) {
2027: debug2("channel %d: not open", c->self);
2028: chan_mark_dead(ssh, c);
1.41 markus 2029: return -1;
1.367 djm 2030: } else {
2031: chan_write_failed(ssh, c);
1.91 markus 2032: }
1.367 djm 2033: return -1;
2034: }
2035: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2036: if (tcgetattr(c->wfd, &tio) == 0 &&
2037: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2038: /*
2039: * Simulate echo to reduce the impact of
2040: * traffic analysis. We need to match the
2041: * size of a SSH2_MSG_CHANNEL_DATA message
2042: * (4 byte channel id + buf)
2043: */
2044: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2045: (r = sshpkt_send(ssh)) != 0)
2046: fatal("%s: channel %d: ignore: %s",
2047: __func__, c->self, ssh_err(r));
1.25 markus 2048: }
1.367 djm 2049: }
2050: if ((r = sshbuf_consume(c->output, len)) != 0) {
2051: fatal("%s: channel %d: consume: %s",
2052: __func__, c->self, ssh_err(r));
1.44 markus 2053: }
1.309 djm 2054: out:
1.367 djm 2055: c->local_consumed += olen - sshbuf_len(c->output);
2056:
2057: return 1;
2058: }
2059:
2060: static int
2061: channel_handle_efd_write(struct ssh *ssh, Channel *c,
2062: fd_set *readset, fd_set *writeset)
2063: {
2064: int r;
2065: ssize_t len;
2066:
2067: if (!FD_ISSET(c->efd, writeset) || sshbuf_len(c->extended) == 0)
2068: return 1;
2069:
2070: len = write(c->efd, sshbuf_ptr(c->extended),
2071: sshbuf_len(c->extended));
2072: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 ! deraadt 2073: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2074: return 1;
2075: if (len <= 0) {
2076: debug2("channel %d: closing write-efd %d", c->self, c->efd);
2077: channel_close_fd(ssh, &c->efd);
2078: } else {
2079: if ((r = sshbuf_consume(c->extended, len)) != 0) {
2080: fatal("%s: channel %d: consume: %s",
2081: __func__, c->self, ssh_err(r));
2082: }
2083: c->local_consumed += len;
2084: }
1.44 markus 2085: return 1;
2086: }
1.241 deraadt 2087:
1.127 itojun 2088: static int
1.367 djm 2089: channel_handle_efd_read(struct ssh *ssh, Channel *c,
2090: fd_set *readset, fd_set *writeset)
1.44 markus 2091: {
1.214 markus 2092: char buf[CHAN_RBUF];
1.367 djm 2093: int r;
2094: ssize_t len;
2095:
2096: if (!FD_ISSET(c->efd, readset))
2097: return 1;
1.44 markus 2098:
1.367 djm 2099: len = read(c->efd, buf, sizeof(buf));
2100: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 ! deraadt 2101: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2102: return 1;
2103: if (len <= 0) {
2104: debug2("channel %d: closing read-efd %d",
2105: c->self, c->efd);
2106: channel_close_fd(ssh, &c->efd);
2107: } else {
2108: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
2109: debug3("channel %d: discard efd",
2110: c->self);
2111: } else if ((r = sshbuf_put(c->extended, buf, len)) != 0) {
2112: fatal("%s: channel %d: append: %s",
2113: __func__, c->self, ssh_err(r));
1.44 markus 2114: }
2115: }
2116: return 1;
2117: }
1.241 deraadt 2118:
1.127 itojun 2119: static int
1.367 djm 2120: channel_handle_efd(struct ssh *ssh, Channel *c,
2121: fd_set *readset, fd_set *writeset)
1.44 markus 2122: {
1.367 djm 2123: if (c->efd == -1)
2124: return 1;
2125:
2126: /** XXX handle drain efd, too */
2127:
2128: if (c->extended_usage == CHAN_EXTENDED_WRITE)
2129: return channel_handle_efd_write(ssh, c, readset, writeset);
2130: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2131: c->extended_usage == CHAN_EXTENDED_IGNORE)
2132: return channel_handle_efd_read(ssh, c, readset, writeset);
2133:
2134: return 1;
2135: }
2136:
2137: static int
2138: channel_check_window(struct ssh *ssh, Channel *c)
2139: {
2140: int r;
2141:
1.104 markus 2142: if (c->type == SSH_CHANNEL_OPEN &&
2143: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2144: ((c->local_window_max - c->local_window >
1.269 markus 2145: c->local_maxpacket*3) ||
2146: c->local_window < c->local_window_max/2) &&
1.44 markus 2147: c->local_consumed > 0) {
1.368 djm 2148: if (!c->have_remote_id)
2149: fatal(":%s: channel %d: no remote id",
2150: __func__, c->self);
1.367 djm 2151: if ((r = sshpkt_start(ssh,
2152: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2153: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2154: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2155: (r = sshpkt_send(ssh)) != 0) {
2156: fatal("%s: channel %i: %s", __func__,
2157: c->self, ssh_err(r));
2158: }
1.70 markus 2159: debug2("channel %d: window %d sent adjust %d",
1.44 markus 2160: c->self, c->local_window,
2161: c->local_consumed);
2162: c->local_window += c->local_consumed;
2163: c->local_consumed = 0;
1.1 deraadt 2164: }
1.41 markus 2165: return 1;
1.1 deraadt 2166: }
2167:
1.127 itojun 2168: static void
1.367 djm 2169: channel_post_open(struct ssh *ssh, Channel *c,
2170: fd_set *readset, fd_set *writeset)
1.41 markus 2171: {
1.367 djm 2172: channel_handle_rfd(ssh, c, readset, writeset);
2173: channel_handle_wfd(ssh, c, readset, writeset);
2174: channel_handle_efd(ssh, c, readset, writeset);
2175: channel_check_window(ssh, c);
1.44 markus 2176: }
2177:
1.302 djm 2178: static u_int
1.367 djm 2179: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2180: {
2181: char buf[CHAN_RBUF];
1.367 djm 2182: ssize_t len;
1.302 djm 2183: u_int rlen;
1.367 djm 2184: int r;
1.302 djm 2185:
1.367 djm 2186: if (sshbuf_len(c->input) < need) {
2187: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2188: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 ! deraadt 2189: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2190: return sshbuf_len(c->input);
1.302 djm 2191: if (len <= 0) {
1.367 djm 2192: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2193: c->self, c->rfd, len);
1.367 djm 2194: chan_read_failed(ssh, c);
1.349 naddy 2195: return 0;
1.367 djm 2196: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
2197: fatal("%s: channel %d: append: %s",
2198: __func__, c->self, ssh_err(r));
2199: }
1.302 djm 2200: }
1.367 djm 2201: return sshbuf_len(c->input);
1.302 djm 2202: }
2203:
2204: static void
1.367 djm 2205: channel_post_mux_client_read(struct ssh *ssh, Channel *c,
2206: fd_set *readset, fd_set *writeset)
1.302 djm 2207: {
2208: u_int need;
2209:
1.367 djm 2210: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
2211: return;
2212: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2213: return;
2214: if (c->mux_pause)
2215: return;
2216:
2217: /*
2218: * Don't not read past the precise end of packets to
2219: * avoid disrupting fd passing.
2220: */
2221: if (read_mux(ssh, c, 4) < 4) /* read header */
2222: return;
2223: /* XXX sshbuf_peek_u32 */
2224: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2225: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2226: if (need > CHANNEL_MUX_MAX_PACKET) {
2227: debug2("channel %d: packet too big %u > %u",
2228: c->self, CHANNEL_MUX_MAX_PACKET, need);
2229: chan_rcvd_oclose(ssh, c);
2230: return;
2231: }
2232: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2233: return;
2234: if (c->mux_rcb(ssh, c) != 0) {
2235: debug("channel %d: mux_rcb failed", c->self);
2236: chan_mark_dead(ssh, c);
2237: return;
1.302 djm 2238: }
1.367 djm 2239: }
2240:
2241: static void
2242: channel_post_mux_client_write(struct ssh *ssh, Channel *c,
2243: fd_set *readset, fd_set *writeset)
2244: {
2245: ssize_t len;
2246: int r;
1.302 djm 2247:
1.367 djm 2248: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
2249: sshbuf_len(c->output) == 0)
2250: return;
2251:
2252: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 ! deraadt 2253: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2254: return;
2255: if (len <= 0) {
2256: chan_mark_dead(ssh, c);
2257: return;
1.302 djm 2258: }
1.367 djm 2259: if ((r = sshbuf_consume(c->output, len)) != 0)
2260: fatal("%s: channel %d: consume: %s", __func__,
2261: c->self, ssh_err(r));
2262: }
2263:
2264: static void
2265: channel_post_mux_client(struct ssh *ssh, Channel *c,
2266: fd_set *readset, fd_set *writeset)
2267: {
2268: channel_post_mux_client_read(ssh, c, readset, writeset);
2269: channel_post_mux_client_write(ssh, c, readset, writeset);
1.302 djm 2270: }
2271:
2272: static void
1.367 djm 2273: channel_post_mux_listener(struct ssh *ssh, Channel *c,
2274: fd_set *readset, fd_set *writeset)
1.302 djm 2275: {
2276: Channel *nc;
2277: struct sockaddr_storage addr;
2278: socklen_t addrlen;
2279: int newsock;
2280: uid_t euid;
2281: gid_t egid;
2282:
2283: if (!FD_ISSET(c->sock, readset))
2284: return;
2285:
2286: debug("multiplexing control connection");
2287:
2288: /*
2289: * Accept connection on control socket
2290: */
2291: memset(&addr, 0, sizeof(addr));
2292: addrlen = sizeof(addr);
2293: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2294: &addrlen)) == -1) {
2295: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 2296: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2297: c->notbefore = monotime() + 1;
1.302 djm 2298: return;
2299: }
2300:
1.393 ! deraadt 2301: if (getpeereid(newsock, &euid, &egid) == -1) {
1.302 djm 2302: error("%s getpeereid failed: %s", __func__,
2303: strerror(errno));
2304: close(newsock);
2305: return;
2306: }
2307: if ((euid != 0) && (getuid() != euid)) {
2308: error("multiplex uid mismatch: peer euid %u != uid %u",
2309: (u_int)euid, (u_int)getuid());
2310: close(newsock);
2311: return;
2312: }
1.367 djm 2313: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2314: newsock, newsock, -1, c->local_window_max,
2315: c->local_maxpacket, 0, "mux-control", 1);
2316: nc->mux_rcb = c->mux_rcb;
1.367 djm 2317: debug3("%s: new mux channel %d fd %d", __func__, nc->self, nc->sock);
1.302 djm 2318: /* establish state */
1.367 djm 2319: nc->mux_rcb(ssh, nc);
1.302 djm 2320: /* mux state transitions must not elicit protocol messages */
2321: nc->flags |= CHAN_LOCAL;
2322: }
2323:
1.127 itojun 2324: static void
1.367 djm 2325: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2326: {
1.367 djm 2327: chan_fn **pre, **post;
2328:
2329: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
2330: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
2331: fatal("%s: allocation failed", __func__);
2332:
2333: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2334: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2335: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2336: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2337: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2338: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2339: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2340: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2341: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2342: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2343: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2344: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2345: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2346:
2347: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2348: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2349: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2350: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2351: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2352: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2353: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2354: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2355: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2356: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2357: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2358: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2359:
1.367 djm 2360: sc->channel_pre = pre;
2361: sc->channel_post = post;
1.44 markus 2362: }
2363:
1.140 markus 2364: /* gc dead channels */
2365: static void
1.367 djm 2366: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2367: {
2368: if (c == NULL)
2369: return;
2370: if (c->detach_user != NULL) {
1.367 djm 2371: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2372: return;
1.385 djm 2373:
1.194 markus 2374: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2375: c->detach_user(ssh, c->self, NULL);
1.140 markus 2376: /* if we still have a callback */
2377: if (c->detach_user != NULL)
2378: return;
1.194 markus 2379: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2380: }
1.367 djm 2381: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2382: return;
1.194 markus 2383: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2384: channel_free(ssh, c);
1.140 markus 2385: }
2386:
1.367 djm 2387: enum channel_table { CHAN_PRE, CHAN_POST };
2388:
1.127 itojun 2389: static void
1.367 djm 2390: channel_handler(struct ssh *ssh, int table,
1.366 djm 2391: fd_set *readset, fd_set *writeset, time_t *unpause_secs)
1.41 markus 2392: {
1.367 djm 2393: struct ssh_channels *sc = ssh->chanctxt;
2394: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2395: u_int i, oalloc;
1.41 markus 2396: Channel *c;
1.317 djm 2397: time_t now;
1.25 markus 2398:
1.322 dtucker 2399: now = monotime();
1.317 djm 2400: if (unpause_secs != NULL)
2401: *unpause_secs = 0;
1.367 djm 2402: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2403: c = sc->channels[i];
1.113 markus 2404: if (c == NULL)
1.41 markus 2405: continue;
1.299 markus 2406: if (c->delayed) {
1.367 djm 2407: if (table == CHAN_PRE)
1.299 markus 2408: c->delayed = 0;
2409: else
2410: continue;
2411: }
1.317 djm 2412: if (ftab[c->type] != NULL) {
2413: /*
2414: * Run handlers that are not paused.
2415: */
2416: if (c->notbefore <= now)
1.367 djm 2417: (*ftab[c->type])(ssh, c, readset, writeset);
1.317 djm 2418: else if (unpause_secs != NULL) {
2419: /*
2420: * Collect the time that the earliest
2421: * channel comes off pause.
2422: */
2423: debug3("%s: chan %d: skip for %d more seconds",
2424: __func__, c->self,
2425: (int)(c->notbefore - now));
2426: if (*unpause_secs == 0 ||
2427: (c->notbefore - now) < *unpause_secs)
2428: *unpause_secs = c->notbefore - now;
2429: }
2430: }
1.367 djm 2431: channel_garbage_collect(ssh, c);
1.1 deraadt 2432: }
1.317 djm 2433: if (unpause_secs != NULL && *unpause_secs != 0)
2434: debug3("%s: first channel unpauses in %d seconds",
2435: __func__, (int)*unpause_secs);
1.1 deraadt 2436: }
2437:
1.121 markus 2438: /*
1.372 markus 2439: * Create sockets before allocating the select bitmasks.
2440: * This is necessary for things that need to happen after reading
2441: * the network-input but before channel_prepare_select().
2442: */
2443: static void
2444: channel_before_prepare_select(struct ssh *ssh)
2445: {
2446: struct ssh_channels *sc = ssh->chanctxt;
2447: Channel *c;
2448: u_int i, oalloc;
2449:
2450: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2451: c = sc->channels[i];
2452: if (c == NULL)
2453: continue;
2454: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
2455: channel_before_prepare_select_rdynamic(ssh, c);
2456: }
2457: }
2458:
2459: /*
1.121 markus 2460: * Allocate/update select bitmasks and add any bits relevant to channels in
2461: * select bitmasks.
2462: */
1.49 markus 2463: void
1.366 djm 2464: channel_prepare_select(struct ssh *ssh, fd_set **readsetp, fd_set **writesetp,
2465: int *maxfdp, u_int *nallocp, time_t *minwait_secs)
1.41 markus 2466: {
1.243 djm 2467: u_int n, sz, nfdset;
1.84 markus 2468:
1.372 markus 2469: channel_before_prepare_select(ssh); /* might update channel_max_fd */
2470:
1.367 djm 2471: n = MAXIMUM(*maxfdp, ssh->chanctxt->channel_max_fd);
1.84 markus 2472:
1.243 djm 2473: nfdset = howmany(n+1, NFDBITS);
2474: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2475: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2476: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2477: sz = nfdset * sizeof(fd_mask);
2478:
1.132 markus 2479: /* perhaps check sz < nalloc/2 and shrink? */
2480: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2481: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2482: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2483: *nallocp = sz;
1.84 markus 2484: }
1.132 markus 2485: *maxfdp = n;
1.84 markus 2486: memset(*readsetp, 0, sz);
2487: memset(*writesetp, 0, sz);
2488:
1.366 djm 2489: if (!ssh_packet_is_rekeying(ssh))
1.367 djm 2490: channel_handler(ssh, CHAN_PRE, *readsetp, *writesetp,
1.317 djm 2491: minwait_secs);
1.41 markus 2492: }
2493:
1.121 markus 2494: /*
2495: * After select, perform any appropriate operations for channels which have
2496: * events pending.
2497: */
1.49 markus 2498: void
1.366 djm 2499: channel_after_select(struct ssh *ssh, fd_set *readset, fd_set *writeset)
1.41 markus 2500: {
1.367 djm 2501: channel_handler(ssh, CHAN_POST, readset, writeset, NULL);
2502: }
2503:
2504: /*
2505: * Enqueue data for channels with open or draining c->input.
2506: */
2507: static void
2508: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2509: {
1.373 djm 2510: size_t len, plen;
2511: const u_char *pkt;
1.367 djm 2512: int r;
2513:
2514: if ((len = sshbuf_len(c->input)) == 0) {
2515: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2516: /*
2517: * input-buffer is empty and read-socket shutdown:
2518: * tell peer, that we will not send more data:
2519: * send IEOF.
2520: * hack for extended data: delay EOF if EFD still
2521: * in use.
2522: */
2523: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2524: debug2("channel %d: "
2525: "ibuf_empty delayed efd %d/(%zu)",
2526: c->self, c->efd, sshbuf_len(c->extended));
2527: else
2528: chan_ibuf_empty(ssh, c);
2529: }
2530: return;
2531: }
2532:
1.368 djm 2533: if (!c->have_remote_id)
2534: fatal(":%s: channel %d: no remote id", __func__, c->self);
2535:
1.367 djm 2536: if (c->datagram) {
2537: /* Check datagram will fit; drop if not */
1.373 djm 2538: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
2539: fatal("%s: channel %d: get datagram: %s", __func__,
1.367 djm 2540: c->self, ssh_err(r));
2541: /*
2542: * XXX this does tail-drop on the datagram queue which is
2543: * usually suboptimal compared to head-drop. Better to have
2544: * backpressure at read time? (i.e. read + discard)
2545: */
1.373 djm 2546: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2547: debug("channel %d: datagram too big", c->self);
2548: return;
2549: }
2550: /* Enqueue it */
2551: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2552: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2553: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.367 djm 2554: (r = sshpkt_send(ssh)) != 0) {
2555: fatal("%s: channel %i: datagram: %s", __func__,
2556: c->self, ssh_err(r));
2557: }
1.373 djm 2558: c->remote_window -= plen;
1.367 djm 2559: return;
2560: }
2561:
2562: /* Enqueue packet for buffered data. */
2563: if (len > c->remote_window)
2564: len = c->remote_window;
2565: if (len > c->remote_maxpacket)
2566: len = c->remote_maxpacket;
2567: if (len == 0)
2568: return;
2569: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2570: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2571: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
2572: (r = sshpkt_send(ssh)) != 0) {
2573: fatal("%s: channel %i: data: %s", __func__,
2574: c->self, ssh_err(r));
2575: }
2576: if ((r = sshbuf_consume(c->input, len)) != 0)
2577: fatal("%s: channel %i: consume: %s", __func__,
2578: c->self, ssh_err(r));
2579: c->remote_window -= len;
1.41 markus 2580: }
2581:
1.367 djm 2582: /*
2583: * Enqueue data for channels with open c->extended in read mode.
2584: */
2585: static void
2586: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2587: {
2588: size_t len;
2589: int r;
2590:
2591: if ((len = sshbuf_len(c->extended)) == 0)
2592: return;
2593:
2594: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2595: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2596: if (len > c->remote_window)
2597: len = c->remote_window;
2598: if (len > c->remote_maxpacket)
2599: len = c->remote_maxpacket;
2600: if (len == 0)
2601: return;
1.368 djm 2602: if (!c->have_remote_id)
2603: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.367 djm 2604: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2605: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2606: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2607: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
2608: (r = sshpkt_send(ssh)) != 0) {
2609: fatal("%s: channel %i: data: %s", __func__,
2610: c->self, ssh_err(r));
2611: }
2612: if ((r = sshbuf_consume(c->extended, len)) != 0)
2613: fatal("%s: channel %i: consume: %s", __func__,
2614: c->self, ssh_err(r));
2615: c->remote_window -= len;
2616: debug2("channel %d: sent ext data %zu", c->self, len);
2617: }
1.121 markus 2618:
1.84 markus 2619: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2620: void
1.367 djm 2621: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2622: {
1.367 djm 2623: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2624: Channel *c;
1.367 djm 2625: u_int i;
1.1 deraadt 2626:
1.367 djm 2627: for (i = 0; i < sc->channels_alloc; i++) {
2628: c = sc->channels[i];
1.113 markus 2629: if (c == NULL)
2630: continue;
1.37 markus 2631:
1.121 markus 2632: /*
2633: * We are only interested in channels that can have buffered
2634: * incoming data.
2635: */
1.358 djm 2636: if (c->type != SSH_CHANNEL_OPEN)
2637: continue;
2638: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2639: /* XXX is this true? */
1.367 djm 2640: debug3("channel %d: will not send data after close",
2641: c->self);
1.44 markus 2642: continue;
2643: }
1.25 markus 2644:
2645: /* Get the amount of buffered data for this channel. */
1.367 djm 2646: if (c->istate == CHAN_INPUT_OPEN ||
2647: c->istate == CHAN_INPUT_WAIT_DRAIN)
2648: channel_output_poll_input_open(ssh, c);
1.44 markus 2649: /* Send extended data, i.e. stderr */
1.358 djm 2650: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2651: c->extended_usage == CHAN_EXTENDED_READ)
2652: channel_output_poll_extended_read(ssh, c);
1.25 markus 2653: }
1.1 deraadt 2654: }
2655:
1.354 markus 2656: /* -- mux proxy support */
2657:
2658: /*
2659: * When multiplexing channel messages for mux clients we have to deal
2660: * with downstream messages from the mux client and upstream messages
2661: * from the ssh server:
2662: * 1) Handling downstream messages is straightforward and happens
2663: * in channel_proxy_downstream():
2664: * - We forward all messages (mostly) unmodified to the server.
2665: * - However, in order to route messages from upstream to the correct
2666: * downstream client, we have to replace the channel IDs used by the
2667: * mux clients with a unique channel ID because the mux clients might
2668: * use conflicting channel IDs.
2669: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2670: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2671: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2672: * with the newly allocated channel ID.
2673: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 2674: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 2675: * is then translated back to the original mux client ID.
2676: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2677: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2678: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2679: * downstream mux client are removed.
2680: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2681: * requires more work, because they are not addressed to a specific
2682: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2683: * out whether the request is addressed to the local client or a
2684: * specific downstream client based on the listen-address/port.
1.380 djm 2685: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 2686: * not supported as the matching session/channel cannot be identified
2687: * easily.
2688: */
2689:
2690: /*
2691: * receive packets from downstream mux clients:
2692: * channel callback fired on read from mux client, creates
2693: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2694: * on channel creation.
2695: */
2696: int
1.367 djm 2697: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2698: {
2699: Channel *c = NULL;
2700: struct sshbuf *original = NULL, *modified = NULL;
2701: const u_char *cp;
2702: char *ctype = NULL, *listen_host = NULL;
2703: u_char type;
2704: size_t have;
1.370 djm 2705: int ret = -1, r;
1.355 djm 2706: u_int id, remote_id, listen_port;
1.354 markus 2707:
1.367 djm 2708: /* sshbuf_dump(downstream->input, stderr); */
2709: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2710: != 0) {
2711: error("%s: malformed message: %s", __func__, ssh_err(r));
2712: return -1;
2713: }
2714: if (have < 2) {
2715: error("%s: short message", __func__);
2716: return -1;
2717: }
2718: type = cp[1];
2719: /* skip padlen + type */
2720: cp += 2;
2721: have -= 2;
2722: if (ssh_packet_log_type(type))
2723: debug3("%s: channel %u: down->up: type %u", __func__,
2724: downstream->self, type);
2725:
2726: switch (type) {
2727: case SSH2_MSG_CHANNEL_OPEN:
2728: if ((original = sshbuf_from(cp, have)) == NULL ||
2729: (modified = sshbuf_new()) == NULL) {
2730: error("%s: alloc", __func__);
2731: goto out;
2732: }
2733: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2734: (r = sshbuf_get_u32(original, &id)) != 0) {
2735: error("%s: parse error %s", __func__, ssh_err(r));
2736: goto out;
2737: }
1.367 djm 2738: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2739: -1, -1, -1, 0, 0, 0, ctype, 1);
2740: c->mux_ctx = downstream; /* point to mux client */
2741: c->mux_downstream_id = id; /* original downstream id */
2742: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2743: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2744: (r = sshbuf_putb(modified, original)) != 0) {
2745: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2746: channel_free(ssh, c);
1.354 markus 2747: goto out;
2748: }
2749: break;
2750: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2751: /*
2752: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2753: * need to parse 'remote_id' instead of 'ctype'.
2754: */
2755: if ((original = sshbuf_from(cp, have)) == NULL ||
2756: (modified = sshbuf_new()) == NULL) {
2757: error("%s: alloc", __func__);
2758: goto out;
2759: }
2760: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2761: (r = sshbuf_get_u32(original, &id)) != 0) {
2762: error("%s: parse error %s", __func__, ssh_err(r));
2763: goto out;
2764: }
1.367 djm 2765: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2766: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
2767: c->mux_ctx = downstream; /* point to mux client */
2768: c->mux_downstream_id = id;
2769: c->remote_id = remote_id;
1.368 djm 2770: c->have_remote_id = 1;
1.354 markus 2771: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2772: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2773: (r = sshbuf_putb(modified, original)) != 0) {
2774: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2775: channel_free(ssh, c);
1.354 markus 2776: goto out;
2777: }
2778: break;
2779: case SSH2_MSG_GLOBAL_REQUEST:
2780: if ((original = sshbuf_from(cp, have)) == NULL) {
2781: error("%s: alloc", __func__);
2782: goto out;
2783: }
2784: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
2785: error("%s: parse error %s", __func__, ssh_err(r));
2786: goto out;
2787: }
2788: if (strcmp(ctype, "tcpip-forward") != 0) {
2789: error("%s: unsupported request %s", __func__, ctype);
2790: goto out;
2791: }
2792: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2793: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2794: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
2795: error("%s: parse error %s", __func__, ssh_err(r));
2796: goto out;
2797: }
1.355 djm 2798: if (listen_port > 65535) {
2799: error("%s: tcpip-forward for %s: bad port %u",
2800: __func__, listen_host, listen_port);
2801: goto out;
2802: }
1.354 markus 2803: /* Record that connection to this host/port is permitted. */
1.381 djm 2804: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 2805: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 2806: listen_host = NULL;
2807: break;
2808: case SSH2_MSG_CHANNEL_CLOSE:
2809: if (have < 4)
2810: break;
2811: remote_id = PEEK_U32(cp);
1.367 djm 2812: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 2813: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 2814: channel_free(ssh, c);
1.354 markus 2815: else
2816: c->flags |= CHAN_CLOSE_SENT;
2817: }
2818: break;
2819: }
2820: if (modified) {
2821: if ((r = sshpkt_start(ssh, type)) != 0 ||
2822: (r = sshpkt_putb(ssh, modified)) != 0 ||
2823: (r = sshpkt_send(ssh)) != 0) {
2824: error("%s: send %s", __func__, ssh_err(r));
2825: goto out;
2826: }
2827: } else {
2828: if ((r = sshpkt_start(ssh, type)) != 0 ||
2829: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2830: (r = sshpkt_send(ssh)) != 0) {
2831: error("%s: send %s", __func__, ssh_err(r));
2832: goto out;
2833: }
2834: }
2835: ret = 0;
2836: out:
2837: free(ctype);
2838: free(listen_host);
2839: sshbuf_free(original);
2840: sshbuf_free(modified);
2841: return ret;
2842: }
2843:
2844: /*
2845: * receive packets from upstream server and de-multiplex packets
2846: * to correct downstream:
2847: * implemented as a helper for channel input handlers,
2848: * replaces local (proxy) channel ID with downstream channel ID.
2849: */
2850: int
1.363 markus 2851: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 2852: {
2853: struct sshbuf *b = NULL;
2854: Channel *downstream;
2855: const u_char *cp = NULL;
2856: size_t len;
2857: int r;
2858:
2859: /*
2860: * When receiving packets from the peer we need to check whether we
2861: * need to forward the packets to the mux client. In this case we
1.380 djm 2862: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 2863: * so we can cleanup the channel.
2864: */
2865: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2866: return 0;
2867: if ((downstream = c->mux_ctx) == NULL)
2868: return 0;
2869: switch (type) {
2870: case SSH2_MSG_CHANNEL_CLOSE:
2871: case SSH2_MSG_CHANNEL_DATA:
2872: case SSH2_MSG_CHANNEL_EOF:
2873: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2874: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2875: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2876: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2877: case SSH2_MSG_CHANNEL_SUCCESS:
2878: case SSH2_MSG_CHANNEL_FAILURE:
2879: case SSH2_MSG_CHANNEL_REQUEST:
2880: break;
2881: default:
2882: debug2("%s: channel %u: unsupported type %u", __func__,
2883: c->self, type);
2884: return 0;
2885: }
2886: if ((b = sshbuf_new()) == NULL) {
2887: error("%s: alloc reply", __func__);
2888: goto out;
2889: }
2890: /* get remaining payload (after id) */
2891: cp = sshpkt_ptr(ssh, &len);
2892: if (cp == NULL) {
2893: error("%s: no packet", __func__);
2894: goto out;
2895: }
2896: /* translate id and send to muxclient */
2897: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2898: (r = sshbuf_put_u8(b, type)) != 0 ||
2899: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2900: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 2901: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.354 markus 2902: error("%s: compose for muxclient %s", __func__, ssh_err(r));
2903: goto out;
2904: }
2905: /* sshbuf_dump(b, stderr); */
2906: if (ssh_packet_log_type(type))
2907: debug3("%s: channel %u: up->down: type %u", __func__, c->self,
2908: type);
2909: out:
2910: /* update state */
2911: switch (type) {
2912: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2913: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 2914: if (cp && len > 4) {
1.354 markus 2915: c->remote_id = PEEK_U32(cp);
1.368 djm 2916: c->have_remote_id = 1;
2917: }
1.354 markus 2918: break;
2919: case SSH2_MSG_CHANNEL_CLOSE:
2920: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 2921: channel_free(ssh, c);
1.354 markus 2922: else
2923: c->flags |= CHAN_CLOSE_RCVD;
2924: break;
2925: }
2926: sshbuf_free(b);
2927: return 1;
2928: }
1.121 markus 2929:
2930: /* -- protocol input */
1.249 djm 2931:
1.367 djm 2932: /* Parse a channel ID from the current packet */
2933: static int
2934: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
2935: {
2936: u_int32_t id;
2937: int r;
2938:
2939: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
2940: error("%s: parse id: %s", where, ssh_err(r));
2941: ssh_packet_disconnect(ssh, "Invalid %s message", what);
2942: }
2943: if (id > INT_MAX) {
2944: error("%s: bad channel id %u: %s", where, id, ssh_err(r));
2945: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
2946: }
2947: return (int)id;
2948: }
2949:
2950: /* Lookup a channel from an ID in the current packet */
2951: static Channel *
2952: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
2953: {
2954: int id = channel_parse_id(ssh, where, what);
2955: Channel *c;
2956:
2957: if ((c = channel_lookup(ssh, id)) == NULL) {
2958: ssh_packet_disconnect(ssh,
2959: "%s packet referred to nonexistent channel %d", what, id);
2960: }
2961: return c;
2962: }
2963:
1.339 markus 2964: int
1.363 markus 2965: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2966: {
1.332 djm 2967: const u_char *data;
1.367 djm 2968: size_t data_len, win_len;
2969: Channel *c = channel_from_packet_id(ssh, __func__, "data");
2970: int r;
1.25 markus 2971:
1.363 markus 2972: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2973: return 0;
1.25 markus 2974:
2975: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2976: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 2977: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
2978: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 2979: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2980: return 0;
1.37 markus 2981:
1.25 markus 2982: /* Get the data. */
1.389 djm 2983: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
2984: (r = sshpkt_get_end(ssh)) != 0)
1.367 djm 2985: fatal("%s: channel %d: get data: %s", __func__,
2986: c->self, ssh_err(r));
2987:
1.309 djm 2988: win_len = data_len;
2989: if (c->datagram)
2990: win_len += 4; /* string length header */
1.200 markus 2991:
2992: /*
1.367 djm 2993: * The sending side reduces its window as it sends data, so we
2994: * must 'fake' consumption of the data in order to ensure that window
2995: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 2996: */
1.358 djm 2997: if (c->ostate != CHAN_OUTPUT_OPEN) {
2998: c->local_window -= win_len;
2999: c->local_consumed += win_len;
1.339 markus 3000: return 0;
1.200 markus 3001: }
1.41 markus 3002:
1.358 djm 3003: if (win_len > c->local_maxpacket) {
1.367 djm 3004: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 3005: c->self, win_len, c->local_maxpacket);
1.367 djm 3006: return 0;
1.358 djm 3007: }
3008: if (win_len > c->local_window) {
1.367 djm 3009: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 3010: c->self, win_len, c->local_window);
3011: return 0;
1.44 markus 3012: }
1.358 djm 3013: c->local_window -= win_len;
3014:
1.367 djm 3015: if (c->datagram) {
3016: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
3017: fatal("%s: channel %d: append datagram: %s",
3018: __func__, c->self, ssh_err(r));
3019: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
3020: fatal("%s: channel %d: append data: %s",
3021: __func__, c->self, ssh_err(r));
3022:
1.339 markus 3023: return 0;
1.1 deraadt 3024: }
1.121 markus 3025:
1.339 markus 3026: int
1.363 markus 3027: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 3028: {
1.367 djm 3029: const u_char *data;
3030: size_t data_len;
3031: u_int32_t tcode;
3032: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
3033: int r;
1.44 markus 3034:
1.363 markus 3035: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3036: return 0;
1.44 markus 3037: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 3038: logit("channel %d: ext data for non open", c->self);
1.339 markus 3039: return 0;
1.172 markus 3040: }
3041: if (c->flags & CHAN_EOF_RCVD) {
3042: if (datafellows & SSH_BUG_EXTEOF)
1.367 djm 3043: debug("channel %d: accepting ext data after eof",
3044: c->self);
1.172 markus 3045: else
1.367 djm 3046: ssh_packet_disconnect(ssh, "Received extended_data "
3047: "after EOF on channel %d.", c->self);
3048: }
3049:
3050: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
3051: error("%s: parse tcode: %s", __func__, ssh_err(r));
3052: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3053: }
3054: if (c->efd == -1 ||
3055: c->extended_usage != CHAN_EXTENDED_WRITE ||
3056: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3057: logit("channel %d: bad ext data", c->self);
1.339 markus 3058: return 0;
1.44 markus 3059: }
1.389 djm 3060: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3061: (r = sshpkt_get_end(ssh)) != 0) {
1.367 djm 3062: error("%s: parse data: %s", __func__, ssh_err(r));
3063: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3064: }
3065:
1.44 markus 3066: if (data_len > c->local_window) {
1.367 djm 3067: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3068: c->self, data_len, c->local_window);
1.339 markus 3069: return 0;
1.44 markus 3070: }
1.367 djm 3071: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3072: /* XXX sshpkt_getb? */
3073: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
3074: error("%s: append: %s", __func__, ssh_err(r));
1.44 markus 3075: c->local_window -= data_len;
1.339 markus 3076: return 0;
1.44 markus 3077: }
3078:
1.339 markus 3079: int
1.363 markus 3080: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3081: {
1.367 djm 3082: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3083: int r;
1.367 djm 3084:
1.389 djm 3085: if ((r = sshpkt_get_end(ssh)) != 0) {
3086: error("%s: parse data: %s", __func__, ssh_err(r));
3087: ssh_packet_disconnect(ssh, "Invalid ieof message");
3088: }
1.41 markus 3089:
1.363 markus 3090: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3091: return 0;
1.367 djm 3092: chan_rcvd_ieof(ssh, c);
1.133 markus 3093:
3094: /* XXX force input close */
1.156 markus 3095: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3096: debug("channel %d: FORCE input drain", c->self);
3097: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3098: if (sshbuf_len(c->input) == 0)
3099: chan_ibuf_empty(ssh, c);
1.133 markus 3100: }
1.339 markus 3101: return 0;
1.41 markus 3102: }
1.1 deraadt 3103:
1.339 markus 3104: int
1.363 markus 3105: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3106: {
1.367 djm 3107: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3108: int r;
1.151 markus 3109:
1.363 markus 3110: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3111: return 0;
1.389 djm 3112: if ((r = sshpkt_get_end(ssh)) != 0) {
3113: error("%s: parse data: %s", __func__, ssh_err(r));
3114: ssh_packet_disconnect(ssh, "Invalid oclose message");
3115: }
1.367 djm 3116: chan_rcvd_oclose(ssh, c);
1.339 markus 3117: return 0;
1.1 deraadt 3118: }
3119:
1.339 markus 3120: int
1.363 markus 3121: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3122: {
1.367 djm 3123: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3124: u_int32_t remote_window, remote_maxpacket;
3125: int r;
1.25 markus 3126:
1.363 markus 3127: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3128: return 0;
3129: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3130: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3131: "non-opening channel %d.", c->self);
3132: /*
3133: * Record the remote channel number and mark that the channel
3134: * is now open.
3135: */
1.368 djm 3136: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3137: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3138: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3139: (r = sshpkt_get_end(ssh)) != 0) {
1.367 djm 3140: error("%s: window/maxpacket: %s", __func__, ssh_err(r));
1.389 djm 3141: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3142: }
3143:
1.368 djm 3144: c->have_remote_id = 1;
1.367 djm 3145: c->remote_window = remote_window;
3146: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3147: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3148: if (c->open_confirm) {
1.367 djm 3149: debug2("%s: channel %d: callback start", __func__, c->self);
3150: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
3151: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3152: }
1.358 djm 3153: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3154: c->remote_window, c->remote_maxpacket);
1.339 markus 3155: return 0;
1.1 deraadt 3156: }
3157:
1.127 itojun 3158: static char *
1.114 markus 3159: reason2txt(int reason)
3160: {
1.143 deraadt 3161: switch (reason) {
1.114 markus 3162: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3163: return "administratively prohibited";
3164: case SSH2_OPEN_CONNECT_FAILED:
3165: return "connect failed";
3166: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3167: return "unknown channel type";
3168: case SSH2_OPEN_RESOURCE_SHORTAGE:
3169: return "resource shortage";
3170: }
1.117 stevesk 3171: return "unknown reason";
1.114 markus 3172: }
3173:
1.339 markus 3174: int
1.363 markus 3175: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3176: {
1.367 djm 3177: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3178: u_int32_t reason;
3179: char *msg = NULL;
3180: int r;
1.25 markus 3181:
1.363 markus 3182: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3183: return 0;
3184: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3185: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3186: "non-opening channel %d.", c->self);
3187: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
3188: error("%s: reason: %s", __func__, ssh_err(r));
1.389 djm 3189: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3190: }
1.378 djm 3191: /* skip language */
3192: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3193: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3194: (r = sshpkt_get_end(ssh)) != 0) {
1.378 djm 3195: error("%s: message/lang: %s", __func__, ssh_err(r));
1.389 djm 3196: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3197: }
1.367 djm 3198: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3199: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3200: free(msg);
3201: if (c->open_confirm) {
1.367 djm 3202: debug2("%s: channel %d: callback start", __func__, c->self);
3203: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
3204: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3205: }
1.291 djm 3206: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3207: chan_mark_dead(ssh, c);
1.339 markus 3208: return 0;
1.44 markus 3209: }
3210:
1.339 markus 3211: int
1.363 markus 3212: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3213: {
1.367 djm 3214: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3215: Channel *c;
1.367 djm 3216: u_int32_t adjust;
3217: u_int new_rwin;
3218: int r;
1.1 deraadt 3219:
1.367 djm 3220: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3221: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3222: return 0;
1.372 markus 3223: }
1.367 djm 3224:
1.363 markus 3225: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3226: return 0;
1.389 djm 3227: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3228: (r = sshpkt_get_end(ssh)) != 0) {
1.367 djm 3229: error("%s: adjust: %s", __func__, ssh_err(r));
1.389 djm 3230: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3231: }
3232: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3233: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3234: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3235: c->self, adjust, c->remote_window);
3236: }
3237: c->remote_window = new_rwin;
1.339 markus 3238: return 0;
1.121 markus 3239: }
1.1 deraadt 3240:
1.339 markus 3241: int
1.363 markus 3242: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3243: {
1.367 djm 3244: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3245: Channel *c;
3246: struct channel_confirm *cc;
1.389 djm 3247: int r;
1.275 djm 3248:
3249: /* Reset keepalive timeout */
1.389 djm 3250: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3251:
1.367 djm 3252: debug2("%s: type %d id %d", __func__, type, id);
1.275 djm 3253:
1.367 djm 3254: if ((c = channel_lookup(ssh, id)) == NULL) {
3255: logit("%s: %d: unknown", __func__, id);
1.339 markus 3256: return 0;
1.367 djm 3257: }
1.363 markus 3258: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3259: return 0;
1.389 djm 3260: if ((r = sshpkt_get_end(ssh)) != 0)
3261: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3262: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3263: return 0;
1.367 djm 3264: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3265: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 3266: explicit_bzero(cc, sizeof(*cc));
1.321 djm 3267: free(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) {
3327: /* Accept localhost address when GatewayPorts=yes */
3328: addr = listen_addr;
1.326 djm 3329: }
1.334 djm 3330: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3331: strcmp(listen_addr, "::1") == 0) {
3332: /*
3333: * If a specific IPv4/IPv6 localhost address has been
3334: * requested then accept it even if gateway_ports is in
3335: * effect. This allows the client to prefer IPv4 or IPv6.
3336: */
3337: addr = listen_addr;
1.312 djm 3338: }
3339: if (wildcardp != NULL)
3340: *wildcardp = wildcard;
3341: return addr;
3342: }
3343:
1.160 markus 3344: static int
1.367 djm 3345: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3346: struct Forward *fwd, int *allocated_listen_port,
3347: struct ForwardOptions *fwd_opts)
1.25 markus 3348: {
1.113 markus 3349: Channel *c;
1.226 djm 3350: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3351: struct addrinfo hints, *ai, *aitop;
1.212 djm 3352: const char *host, *addr;
1.35 markus 3353: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3354: in_port_t *lport_p;
1.25 markus 3355:
1.212 djm 3356: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3357:
1.344 millert 3358: if (is_client && fwd->connect_path != NULL) {
3359: host = fwd->connect_path;
3360: } else {
3361: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3362: fwd->listen_host : fwd->connect_host;
3363: if (host == NULL) {
3364: error("No forward host name.");
3365: return 0;
3366: }
3367: if (strlen(host) >= NI_MAXHOST) {
3368: error("Forward host name too long.");
3369: return 0;
3370: }
1.87 markus 3371: }
1.25 markus 3372:
1.312 djm 3373: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3374: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3375: is_client, fwd_opts);
3376: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 3377: type, wildcard, (addr == NULL) ? "NULL" : addr);
3378:
3379: /*
1.35 markus 3380: * getaddrinfo returns a loopback address if the hostname is
3381: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3382: */
1.35 markus 3383: memset(&hints, 0, sizeof(hints));
1.367 djm 3384: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3385: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3386: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3387: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3388: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3389: if (addr == NULL) {
3390: /* This really shouldn't happen */
1.389 djm 3391: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3392: ssh_gai_strerror(r));
1.212 djm 3393: } else {
1.336 millert 3394: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 3395: ssh_gai_strerror(r));
1.212 djm 3396: }
1.218 markus 3397: return 0;
1.212 djm 3398: }
1.295 djm 3399: if (allocated_listen_port != NULL)
3400: *allocated_listen_port = 0;
1.35 markus 3401: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3402: switch (ai->ai_family) {
3403: case AF_INET:
3404: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3405: sin_port;
3406: break;
3407: case AF_INET6:
3408: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3409: sin6_port;
3410: break;
3411: default:
1.35 markus 3412: continue;
1.295 djm 3413: }
3414: /*
3415: * If allocating a port for -R forwards, then use the
3416: * same port for all address families.
3417: */
1.367 djm 3418: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3419: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3420: *allocated_listen_port > 0)
1.295 djm 3421: *lport_p = htons(*allocated_listen_port);
3422:
1.35 markus 3423: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3424: strport, sizeof(strport),
3425: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 3426: error("%s: getnameinfo failed", __func__);
1.35 markus 3427: continue;
3428: }
3429: /* Create a port to listen for the host. */
1.300 dtucker 3430: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 ! deraadt 3431: if (sock == -1) {
1.35 markus 3432: /* this is no error since kernel may not support ipv6 */
1.377 djm 3433: verbose("socket [%s]:%s: %.100s", ntop, strport,
3434: strerror(errno));
1.35 markus 3435: continue;
3436: }
1.226 djm 3437:
1.376 djm 3438: set_reuseaddr(sock);
1.182 stevesk 3439:
1.295 djm 3440: debug("Local forwarding listening on %s port %s.",
3441: ntop, strport);
1.35 markus 3442:
3443: /* Bind the socket to the address. */
1.393 ! deraadt 3444: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3445: /*
3446: * address can be in if use ipv6 address is
3447: * already bound
3448: */
1.377 djm 3449: verbose("bind [%s]:%s: %.100s",
3450: ntop, strport, strerror(errno));
1.35 markus 3451: close(sock);
3452: continue;
3453: }
3454: /* Start listening for connections on the socket. */
1.393 ! deraadt 3455: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3456: error("listen [%s]:%s: %.100s", ntop, strport,
3457: strerror(errno));
1.35 markus 3458: close(sock);
3459: continue;
3460: }
1.295 djm 3461:
3462: /*
1.336 millert 3463: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3464: * record what we got.
3465: */
1.367 djm 3466: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3467: fwd->listen_port == 0 &&
1.295 djm 3468: allocated_listen_port != NULL &&
3469: *allocated_listen_port == 0) {
1.350 djm 3470: *allocated_listen_port = get_local_port(sock);
1.295 djm 3471: debug("Allocated listen port %d",
3472: *allocated_listen_port);
3473: }
3474:
1.35 markus 3475: /* Allocate a channel number for the socket. */
1.367 djm 3476: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3477: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3478: 0, "port listener", 1);
1.293 djm 3479: c->path = xstrdup(host);
1.336 millert 3480: c->host_port = fwd->connect_port;
1.312 djm 3481: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3482: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 3483: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
3484: c->listening_port = *allocated_listen_port;
3485: else
1.336 millert 3486: c->listening_port = fwd->listen_port;
1.35 markus 3487: success = 1;
3488: }
3489: if (success == 0)
1.336 millert 3490: error("%s: cannot listen to port: %d", __func__,
3491: fwd->listen_port);
1.35 markus 3492: freeaddrinfo(aitop);
1.87 markus 3493: return success;
1.25 markus 3494: }
1.1 deraadt 3495:
1.336 millert 3496: static int
1.367 djm 3497: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3498: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3499: {
3500: struct sockaddr_un sunaddr;
3501: const char *path;
3502: Channel *c;
3503: int port, sock;
3504: mode_t omask;
3505:
3506: switch (type) {
3507: case SSH_CHANNEL_UNIX_LISTENER:
3508: if (fwd->connect_path != NULL) {
3509: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3510: error("Local connecting path too long: %s",
3511: fwd->connect_path);
3512: return 0;
3513: }
3514: path = fwd->connect_path;
3515: port = PORT_STREAMLOCAL;
3516: } else {
3517: if (fwd->connect_host == NULL) {
3518: error("No forward host name.");
3519: return 0;
3520: }
3521: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3522: error("Forward host name too long.");
3523: return 0;
3524: }
3525: path = fwd->connect_host;
3526: port = fwd->connect_port;
3527: }
3528: break;
3529: case SSH_CHANNEL_RUNIX_LISTENER:
3530: path = fwd->listen_path;
3531: port = PORT_STREAMLOCAL;
3532: break;
3533: default:
3534: error("%s: unexpected channel type %d", __func__, type);
3535: return 0;
3536: }
3537:
3538: if (fwd->listen_path == NULL) {
3539: error("No forward path name.");
3540: return 0;
3541: }
3542: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3543: error("Local listening path too long: %s", fwd->listen_path);
3544: return 0;
3545: }
3546:
3547: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
3548:
3549: /* Start a Unix domain listener. */
3550: omask = umask(fwd_opts->streamlocal_bind_mask);
3551: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3552: fwd_opts->streamlocal_bind_unlink);
3553: umask(omask);
3554: if (sock < 0)
3555: return 0;
3556:
3557: debug("Local forwarding listening on path %s.", fwd->listen_path);
3558:
3559: /* Allocate a channel number for the socket. */
1.367 djm 3560: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3561: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3562: 0, "unix listener", 1);
3563: c->path = xstrdup(path);
3564: c->host_port = port;
3565: c->listening_port = PORT_STREAMLOCAL;
3566: c->listening_addr = xstrdup(fwd->listen_path);
3567: return 1;
3568: }
3569:
3570: static int
1.367 djm 3571: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3572: const char *host, u_short port)
1.202 djm 3573: {
1.209 avsm 3574: u_int i;
3575: int found = 0;
1.202 djm 3576:
1.367 djm 3577: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3578: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3579: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3580: continue;
3581: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3582: debug2("%s: close channel %d", __func__, i);
1.367 djm 3583: channel_free(ssh, c);
1.312 djm 3584: found = 1;
3585: }
3586: }
3587:
1.367 djm 3588: return found;
1.312 djm 3589: }
3590:
1.336 millert 3591: static int
1.367 djm 3592: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3593: {
3594: u_int i;
3595: int found = 0;
3596:
1.367 djm 3597: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3598: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3599: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3600: continue;
3601: if (c->path == NULL)
3602: continue;
3603: if (strcmp(c->path, path) == 0) {
3604: debug2("%s: close channel %d", __func__, i);
1.367 djm 3605: channel_free(ssh, c);
1.336 millert 3606: found = 1;
3607: }
3608: }
3609:
1.367 djm 3610: return found;
1.336 millert 3611: }
3612:
1.312 djm 3613: int
1.367 djm 3614: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3615: {
1.367 djm 3616: if (fwd->listen_path != NULL) {
3617: return channel_cancel_rport_listener_streamlocal(ssh,
3618: fwd->listen_path);
3619: } else {
3620: return channel_cancel_rport_listener_tcpip(ssh,
3621: fwd->listen_host, fwd->listen_port);
3622: }
1.336 millert 3623: }
3624:
3625: static int
1.367 djm 3626: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3627: const char *lhost, u_short lport, int cport,
3628: struct ForwardOptions *fwd_opts)
1.312 djm 3629: {
3630: u_int i;
3631: int found = 0;
1.389 djm 3632: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 3633:
1.367 djm 3634: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3635: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3636: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3637: continue;
1.313 markus 3638: if (c->listening_port != lport)
1.312 djm 3639: continue;
1.313 markus 3640: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3641: /* skip dynamic forwardings */
3642: if (c->host_port == 0)
3643: continue;
3644: } else {
3645: if (c->host_port != cport)
3646: continue;
3647: }
1.312 djm 3648: if ((c->listening_addr == NULL && addr != NULL) ||
3649: (c->listening_addr != NULL && addr == NULL))
3650: continue;
3651: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3652: debug2("%s: close channel %d", __func__, i);
1.367 djm 3653: channel_free(ssh, c);
1.202 djm 3654: found = 1;
3655: }
3656: }
3657:
1.367 djm 3658: return found;
1.202 djm 3659: }
3660:
1.336 millert 3661: static int
1.367 djm 3662: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3663: {
3664: u_int i;
3665: int found = 0;
3666:
3667: if (path == NULL) {
3668: error("%s: no path specified.", __func__);
3669: return 0;
3670: }
3671:
1.367 djm 3672: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3673: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3674: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3675: continue;
3676: if (c->listening_addr == NULL)
3677: continue;
3678: if (strcmp(c->listening_addr, path) == 0) {
3679: debug2("%s: close channel %d", __func__, i);
1.367 djm 3680: channel_free(ssh, c);
1.336 millert 3681: found = 1;
3682: }
3683: }
3684:
1.367 djm 3685: return found;
1.336 millert 3686: }
3687:
3688: int
1.367 djm 3689: channel_cancel_lport_listener(struct ssh *ssh,
3690: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3691: {
1.367 djm 3692: if (fwd->listen_path != NULL) {
3693: return channel_cancel_lport_listener_streamlocal(ssh,
3694: fwd->listen_path);
3695: } else {
3696: return channel_cancel_lport_listener_tcpip(ssh,
3697: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3698: }
1.336 millert 3699: }
3700:
1.362 markus 3701: /* protocol local port fwd, used by ssh */
1.160 markus 3702: int
1.367 djm 3703: channel_setup_local_fwd_listener(struct ssh *ssh,
3704: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3705: {
1.336 millert 3706: if (fwd->listen_path != NULL) {
1.367 djm 3707: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3708: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3709: } else {
1.367 djm 3710: return channel_setup_fwd_listener_tcpip(ssh,
3711: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3712: }
1.160 markus 3713: }
3714:
1.381 djm 3715: /* Matches a remote forwarding permission against a requested forwarding */
3716: static int
3717: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
3718: {
3719: int ret;
3720: char *lhost;
3721:
3722: /* XXX add ACLs for streamlocal */
3723: if (fwd->listen_path != NULL)
3724: return 1;
3725:
3726: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
3727: return 0;
3728:
3729: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
3730: allowed_open->listen_port != fwd->listen_port)
3731: return 0;
3732:
3733: /* Match hostnames case-insensitively */
3734: lhost = xstrdup(fwd->listen_host);
3735: lowercase(lhost);
3736: ret = match_pattern(lhost, allowed_open->listen_host);
3737: free(lhost);
3738:
3739: return ret;
3740: }
3741:
3742: /* Checks whether a requested remote forwarding is permitted */
3743: static int
3744: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
3745: {
3746: struct ssh_channels *sc = ssh->chanctxt;
3747: struct permission_set *pset = &sc->remote_perms;
3748: u_int i, permit, permit_adm = 1;
3749: struct permission *perm;
3750:
3751: /* XXX apply GatewayPorts override before checking? */
3752:
3753: permit = pset->all_permitted;
3754: if (!permit) {
3755: for (i = 0; i < pset->num_permitted_user; i++) {
3756: perm = &pset->permitted_user[i];
3757: if (remote_open_match(perm, fwd)) {
3758: permit = 1;
3759: break;
3760: }
3761: }
3762: }
3763:
3764: if (pset->num_permitted_admin > 0) {
3765: permit_adm = 0;
3766: for (i = 0; i < pset->num_permitted_admin; i++) {
3767: perm = &pset->permitted_admin[i];
3768: if (remote_open_match(perm, fwd)) {
3769: permit_adm = 1;
3770: break;
3771: }
3772: }
3773: }
3774:
3775: return permit && permit_adm;
3776: }
3777:
1.160 markus 3778: /* protocol v2 remote port fwd, used by sshd */
3779: int
1.367 djm 3780: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3781: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3782: {
1.381 djm 3783: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 3784: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 3785: if (fwd->listen_path != NULL)
3786: /* XXX always allowed, see remote_open_match() */
3787: logit("Received request from %.100s port %d to "
3788: "remote forward to path \"%.100s\", "
3789: "but the request was denied.",
3790: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3791: fwd->listen_path);
3792: else if(fwd->listen_host != NULL)
3793: logit("Received request from %.100s port %d to "
3794: "remote forward to host %.100s port %d, "
3795: "but the request was denied.",
3796: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3797: fwd->listen_host, fwd->listen_port );
3798: else
3799: logit("Received request from %.100s port %d to remote "
3800: "forward, but the request was denied.",
3801: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 3802: return 0;
3803: }
1.336 millert 3804: if (fwd->listen_path != NULL) {
1.367 djm 3805: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3806: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3807: } else {
1.367 djm 3808: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 3809: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3810: fwd_opts);
3811: }
1.160 markus 3812: }
3813:
1.27 markus 3814: /*
1.312 djm 3815: * Translate the requested rfwd listen host to something usable for
3816: * this server.
3817: */
3818: static const char *
3819: channel_rfwd_bind_host(const char *listen_host)
3820: {
3821: if (listen_host == NULL) {
1.378 djm 3822: return "localhost";
1.312 djm 3823: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 3824: return "";
1.312 djm 3825: } else
3826: return listen_host;
3827: }
3828:
3829: /*
1.27 markus 3830: * Initiate forwarding of connections to port "port" on remote host through
3831: * the secure channel to host:port from local side.
1.315 markus 3832: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 3833: * channel_update_permission().
1.27 markus 3834: */
1.253 markus 3835: int
1.367 djm 3836: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 3837: {
1.367 djm 3838: int r, success = 0, idx = -1;
3839: char *host_to_connect, *listen_host, *listen_path;
3840: int port_to_connect, listen_port;
1.73 markus 3841:
1.25 markus 3842: /* Send the forward request to the remote side. */
1.358 djm 3843: if (fwd->listen_path != NULL) {
1.367 djm 3844: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3845: (r = sshpkt_put_cstring(ssh,
3846: "streamlocal-forward@openssh.com")) != 0 ||
3847: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3848: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3849: (r = sshpkt_send(ssh)) != 0 ||
3850: (r = ssh_packet_write_wait(ssh)) != 0)
3851: fatal("%s: request streamlocal: %s",
3852: __func__, ssh_err(r));
1.336 millert 3853: } else {
1.367 djm 3854: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3855: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
3856: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3857: (r = sshpkt_put_cstring(ssh,
3858: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
3859: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
3860: (r = sshpkt_send(ssh)) != 0 ||
3861: (r = ssh_packet_write_wait(ssh)) != 0)
3862: fatal("%s: request tcpip-forward: %s",
3863: __func__, ssh_err(r));
1.73 markus 3864: }
1.358 djm 3865: /* Assume that server accepts the request */
3866: success = 1;
1.73 markus 3867: if (success) {
1.305 djm 3868: /* Record that connection to this host/port is permitted. */
1.367 djm 3869: host_to_connect = listen_host = listen_path = NULL;
3870: port_to_connect = listen_port = 0;
1.336 millert 3871: if (fwd->connect_path != NULL) {
1.367 djm 3872: host_to_connect = xstrdup(fwd->connect_path);
3873: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 3874: } else {
1.367 djm 3875: host_to_connect = xstrdup(fwd->connect_host);
3876: port_to_connect = fwd->connect_port;
1.336 millert 3877: }
3878: if (fwd->listen_path != NULL) {
1.367 djm 3879: listen_path = xstrdup(fwd->listen_path);
3880: listen_port = PORT_STREAMLOCAL;
1.336 millert 3881: } else {
1.367 djm 3882: if (fwd->listen_host != NULL)
3883: listen_host = xstrdup(fwd->listen_host);
3884: listen_port = fwd->listen_port;
3885: }
1.381 djm 3886: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 3887: host_to_connect, port_to_connect,
3888: listen_host, listen_path, listen_port, NULL);
1.44 markus 3889: }
1.367 djm 3890: return idx;
1.1 deraadt 3891: }
3892:
1.333 markus 3893: static int
1.381 djm 3894: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 3895: int requestedport)
1.333 markus 3896: {
3897: if (allowed_open->host_to_connect == NULL)
3898: return 0;
3899: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3900: allowed_open->port_to_connect != requestedport)
3901: return 0;
1.351 dtucker 3902: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3903: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3904: return 0;
3905: return 1;
3906: }
3907:
3908: /*
1.336 millert 3909: * Note that in the listen host/port case
1.333 markus 3910: * we don't support FWD_PERMIT_ANY_PORT and
3911: * need to translate between the configured-host (listen_host)
3912: * and what we've sent to the remote server (channel_rfwd_bind_host)
3913: */
3914: static int
1.381 djm 3915: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 3916: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3917: {
3918: const char *allowed_host;
3919:
3920: if (allowed_open->host_to_connect == NULL)
3921: return 0;
3922: if (allowed_open->listen_port != requestedport)
3923: return 0;
1.335 djm 3924: if (!translate && allowed_open->listen_host == NULL &&
3925: requestedhost == NULL)
3926: return 1;
1.333 markus 3927: allowed_host = translate ?
3928: channel_rfwd_bind_host(allowed_open->listen_host) :
3929: allowed_open->listen_host;
1.382 djm 3930: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 3931: strcmp(allowed_host, requestedhost) != 0)
3932: return 0;
3933: return 1;
3934: }
3935:
1.336 millert 3936: static int
1.381 djm 3937: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 3938: const char *requestedpath)
3939: {
3940: if (allowed_open->host_to_connect == NULL)
3941: return 0;
3942: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3943: return 0;
3944: if (allowed_open->listen_path == NULL ||
3945: strcmp(allowed_open->listen_path, requestedpath) != 0)
3946: return 0;
3947: return 1;
3948: }
3949:
1.27 markus 3950: /*
1.208 deraadt 3951: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3952: * local side.
3953: */
1.336 millert 3954: static int
1.367 djm 3955: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
3956: const char *host, u_short port)
1.202 djm 3957: {
1.367 djm 3958: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 3959: struct permission_set *pset = &sc->local_perms;
1.367 djm 3960: int r;
3961: u_int i;
1.381 djm 3962: struct permission *perm;
1.202 djm 3963:
1.381 djm 3964: for (i = 0; i < pset->num_permitted_user; i++) {
3965: perm = &pset->permitted_user[i];
3966: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 3967: break;
1.381 djm 3968: perm = NULL;
1.202 djm 3969: }
1.381 djm 3970: if (perm == NULL) {
1.202 djm 3971: debug("%s: requested forward not found", __func__);
1.312 djm 3972: return -1;
1.202 djm 3973: }
1.367 djm 3974: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3975: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
3976: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3977: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
3978: (r = sshpkt_put_u32(ssh, port)) != 0 ||
3979: (r = sshpkt_send(ssh)) != 0)
3980: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3981:
1.381 djm 3982: fwd_perm_clear(perm); /* unregister */
1.336 millert 3983:
3984: return 0;
3985: }
3986:
3987: /*
3988: * Request cancellation of remote forwarding of Unix domain socket
3989: * path from local side.
3990: */
3991: static int
1.367 djm 3992: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3993: {
1.367 djm 3994: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 3995: struct permission_set *pset = &sc->local_perms;
1.367 djm 3996: int r;
3997: u_int i;
1.381 djm 3998: struct permission *perm;
1.336 millert 3999:
1.381 djm 4000: for (i = 0; i < pset->num_permitted_user; i++) {
4001: perm = &pset->permitted_user[i];
4002: if (open_listen_match_streamlocal(perm, path))
1.336 millert 4003: break;
1.381 djm 4004: perm = NULL;
1.336 millert 4005: }
1.381 djm 4006: if (perm == NULL) {
1.336 millert 4007: debug("%s: requested forward not found", __func__);
4008: return -1;
4009: }
1.367 djm 4010: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4011: (r = sshpkt_put_cstring(ssh,
4012: "cancel-streamlocal-forward@openssh.com")) != 0 ||
4013: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4014: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
4015: (r = sshpkt_send(ssh)) != 0)
4016: fatal("%s: send cancel: %s", __func__, ssh_err(r));
4017:
1.381 djm 4018: fwd_perm_clear(perm); /* unregister */
1.312 djm 4019:
4020: return 0;
1.202 djm 4021: }
4022:
4023: /*
1.336 millert 4024: * Request cancellation of remote forwarding of a connection from local side.
4025: */
4026: int
1.367 djm 4027: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 4028: {
4029: if (fwd->listen_path != NULL) {
1.367 djm 4030: return channel_request_rforward_cancel_streamlocal(ssh,
4031: fwd->listen_path);
1.336 millert 4032: } else {
1.367 djm 4033: return channel_request_rforward_cancel_tcpip(ssh,
4034: fwd->listen_host,
4035: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 4036: }
1.1 deraadt 4037: }
4038:
1.99 markus 4039: /*
1.381 djm 4040: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 4041: * usually called by the server, because the user could connect to any port
4042: * anyway, and the server has no way to know but to trust the client anyway.
4043: */
4044: void
1.381 djm 4045: channel_permit_all(struct ssh *ssh, int where)
4046: {
4047: struct permission_set *pset = permission_set_get(ssh, where);
4048:
4049: if (pset->num_permitted_user == 0)
4050: pset->all_permitted = 1;
4051: }
4052:
4053: /*
4054: * Permit the specified host/port for forwarding.
4055: */
4056: void
4057: channel_add_permission(struct ssh *ssh, int who, int where,
4058: char *host, int port)
4059: {
4060: int local = where == FORWARD_LOCAL;
4061: struct permission_set *pset = permission_set_get(ssh, where);
4062:
4063: debug("allow %s forwarding to host %s port %d",
4064: fwd_ident(who, where), host, port);
4065: /*
4066: * Remote forwards set listen_host/port, local forwards set
4067: * host/port_to_connect.
4068: */
4069: permission_set_add(ssh, who, where,
4070: local ? host : 0, local ? port : 0,
4071: local ? NULL : host, NULL, local ? 0 : port, NULL);
4072: pset->all_permitted = 0;
4073: }
4074:
4075: /*
4076: * Administratively disable forwarding.
4077: */
4078: void
4079: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4080: {
1.381 djm 4081: channel_clear_permission(ssh, FORWARD_ADM, where);
4082: permission_set_add(ssh, FORWARD_ADM, where,
4083: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4084: }
4085:
1.381 djm 4086: /*
4087: * Clear a list of permitted opens.
4088: */
1.101 markus 4089: void
1.381 djm 4090: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4091: {
1.381 djm 4092: struct permission **permp;
4093: u_int *npermp;
1.367 djm 4094:
1.381 djm 4095: permission_set_get_array(ssh, who, where, &permp, &npermp);
4096: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4097: *npermp = 0;
1.315 markus 4098: }
4099:
4100: /*
4101: * Update the listen port for a dynamic remote forward, after
4102: * the actual 'newport' has been allocated. If 'newport' < 0 is
4103: * passed then they entry will be invalidated.
4104: */
4105: void
1.381 djm 4106: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4107: {
1.381 djm 4108: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4109:
1.381 djm 4110: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
4111: debug("%s: index out of range: %d num_permitted_user %d",
4112: __func__, idx, pset->num_permitted_user);
1.315 markus 4113: return;
4114: }
4115: debug("%s allowed port %d for forwarding to host %s port %d",
4116: newport > 0 ? "Updating" : "Removing",
4117: newport,
1.381 djm 4118: pset->permitted_user[idx].host_to_connect,
4119: pset->permitted_user[idx].port_to_connect);
1.367 djm 4120: if (newport <= 0)
1.381 djm 4121: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4122: else {
1.381 djm 4123: pset->permitted_user[idx].listen_port =
1.315 markus 4124: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
4125: }
1.99 markus 4126: }
4127:
1.314 dtucker 4128: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4129: int
4130: permitopen_port(const char *p)
4131: {
4132: int port;
4133:
4134: if (strcmp(p, "*") == 0)
4135: return FWD_PERMIT_ANY_PORT;
4136: if ((port = a2port(p)) > 0)
4137: return port;
4138: return -1;
4139: }
4140:
1.276 djm 4141: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4142: static int
1.276 djm 4143: connect_next(struct channel_connect *cctx)
1.41 markus 4144: {
1.276 djm 4145: int sock, saved_errno;
1.336 millert 4146: struct sockaddr_un *sunaddr;
1.367 djm 4147: char ntop[NI_MAXHOST];
4148: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4149:
1.276 djm 4150: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4151: switch (cctx->ai->ai_family) {
4152: case AF_UNIX:
4153: /* unix:pathname instead of host:port */
4154: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4155: strlcpy(ntop, "unix", sizeof(ntop));
4156: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4157: break;
4158: case AF_INET:
4159: case AF_INET6:
4160: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4161: ntop, sizeof(ntop), strport, sizeof(strport),
4162: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
4163: error("connect_next: getnameinfo failed");
4164: continue;
4165: }
4166: break;
4167: default:
1.41 markus 4168: continue;
4169: }
1.300 dtucker 4170: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4171: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4172: if (cctx->ai->ai_next == NULL)
1.186 djm 4173: error("socket: %.100s", strerror(errno));
4174: else
4175: verbose("socket: %.100s", strerror(errno));
1.41 markus 4176: continue;
4177: }
1.205 djm 4178: if (set_nonblock(sock) == -1)
4179: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 4180: if (connect(sock, cctx->ai->ai_addr,
4181: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
4182: debug("connect_next: host %.100s ([%.100s]:%s): "
4183: "%.100s", cctx->host, ntop, strport,
1.41 markus 4184: strerror(errno));
1.276 djm 4185: saved_errno = errno;
1.41 markus 4186: close(sock);
1.276 djm 4187: errno = saved_errno;
1.89 stevesk 4188: continue; /* fail -- try next */
1.41 markus 4189: }
1.336 millert 4190: if (cctx->ai->ai_family != AF_UNIX)
4191: set_nodelay(sock);
1.276 djm 4192: debug("connect_next: host %.100s ([%.100s]:%s) "
4193: "in progress, fd=%d", cctx->host, ntop, strport, sock);
4194: cctx->ai = cctx->ai->ai_next;
4195: return sock;
4196: }
4197: return -1;
4198: }
1.41 markus 4199:
1.276 djm 4200: static void
4201: channel_connect_ctx_free(struct channel_connect *cctx)
4202: {
1.321 djm 4203: free(cctx->host);
1.336 millert 4204: if (cctx->aitop) {
4205: if (cctx->aitop->ai_family == AF_UNIX)
4206: free(cctx->aitop);
4207: else
4208: freeaddrinfo(cctx->aitop);
4209: }
1.329 tedu 4210: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4211: }
4212:
1.357 dtucker 4213: /*
1.372 markus 4214: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4215: * passing back the failure reason if appropriate.
4216: */
1.372 markus 4217: static int
4218: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4219: char *ctype, char *rname, struct channel_connect *cctx,
4220: int *reason, const char **errmsg)
1.276 djm 4221: {
4222: struct addrinfo hints;
4223: int gaierr;
4224: int sock = -1;
4225: char strport[NI_MAXSERV];
1.336 millert 4226:
4227: if (port == PORT_STREAMLOCAL) {
4228: struct sockaddr_un *sunaddr;
4229: struct addrinfo *ai;
4230:
4231: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4232: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4233: return -1;
1.336 millert 4234: }
4235:
4236: /*
4237: * Fake up a struct addrinfo for AF_UNIX connections.
4238: * channel_connect_ctx_free() must check ai_family
4239: * and use free() not freeaddirinfo() for AF_UNIX.
4240: */
4241: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4242: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4243: ai->ai_addr = (struct sockaddr *)(ai + 1);
4244: ai->ai_addrlen = sizeof(*sunaddr);
4245: ai->ai_family = AF_UNIX;
1.372 markus 4246: ai->ai_socktype = socktype;
1.336 millert 4247: ai->ai_protocol = PF_UNSPEC;
4248: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4249: sunaddr->sun_family = AF_UNIX;
4250: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4251: cctx->aitop = ai;
1.336 millert 4252: } else {
4253: memset(&hints, 0, sizeof(hints));
1.367 djm 4254: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4255: hints.ai_socktype = socktype;
1.336 millert 4256: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4257: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4258: != 0) {
4259: if (errmsg != NULL)
4260: *errmsg = ssh_gai_strerror(gaierr);
4261: if (reason != NULL)
4262: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4263: error("connect_to %.100s: unknown host (%s)", name,
4264: ssh_gai_strerror(gaierr));
1.372 markus 4265: return -1;
1.336 millert 4266: }
1.41 markus 4267: }
1.276 djm 4268:
1.372 markus 4269: cctx->host = xstrdup(name);
4270: cctx->port = port;
4271: cctx->ai = cctx->aitop;
1.276 djm 4272:
1.372 markus 4273: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4274: error("connect to %.100s port %d failed: %s",
1.336 millert 4275: name, port, strerror(errno));
1.372 markus 4276: return -1;
4277: }
4278:
4279: return sock;
4280: }
4281:
4282: /* Return CONNECTING channel to remote host:port or local socket path */
4283: static Channel *
4284: connect_to(struct ssh *ssh, const char *host, int port,
4285: char *ctype, char *rname)
4286: {
4287: struct channel_connect cctx;
4288: Channel *c;
4289: int sock;
4290:
4291: memset(&cctx, 0, sizeof(cctx));
4292: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4293: &cctx, NULL, NULL);
4294: if (sock == -1) {
1.276 djm 4295: channel_connect_ctx_free(&cctx);
4296: return NULL;
1.41 markus 4297: }
1.367 djm 4298: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4299: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4300: c->host_port = port;
4301: c->path = xstrdup(host);
1.276 djm 4302: c->connect_ctx = cctx;
1.372 markus 4303:
1.276 djm 4304: return c;
1.41 markus 4305: }
1.99 markus 4306:
1.354 markus 4307: /*
4308: * returns either the newly connected channel or the downstream channel
4309: * that needs to deal with this connection.
4310: */
1.276 djm 4311: Channel *
1.367 djm 4312: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4313: u_short listen_port, char *ctype, char *rname)
1.73 markus 4314: {
1.367 djm 4315: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4316: struct permission_set *pset = &sc->local_perms;
1.367 djm 4317: u_int i;
1.381 djm 4318: struct permission *perm;
1.99 markus 4319:
1.381 djm 4320: for (i = 0; i < pset->num_permitted_user; i++) {
4321: perm = &pset->permitted_user[i];
4322: if (open_listen_match_tcpip(perm,
4323: listen_host, listen_port, 1)) {
4324: if (perm->downstream)
4325: return perm->downstream;
4326: if (perm->port_to_connect == 0)
1.372 markus 4327: return rdynamic_connect_prepare(ssh,
4328: ctype, rname);
1.367 djm 4329: return connect_to(ssh,
1.381 djm 4330: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4331: ctype, rname);
1.276 djm 4332: }
4333: }
1.74 markus 4334: error("WARNING: Server requests forwarding for unknown listen_port %d",
4335: listen_port);
1.276 djm 4336: return NULL;
1.73 markus 4337: }
4338:
1.336 millert 4339: Channel *
1.367 djm 4340: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4341: char *ctype, char *rname)
1.336 millert 4342: {
1.367 djm 4343: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4344: struct permission_set *pset = &sc->local_perms;
1.367 djm 4345: u_int i;
1.381 djm 4346: struct permission *perm;
1.336 millert 4347:
1.381 djm 4348: for (i = 0; i < pset->num_permitted_user; i++) {
4349: perm = &pset->permitted_user[i];
4350: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4351: return connect_to(ssh,
1.381 djm 4352: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4353: ctype, rname);
1.336 millert 4354: }
4355: }
4356: error("WARNING: Server requests forwarding for unknown path %.100s",
4357: path);
4358: return NULL;
4359: }
4360:
1.99 markus 4361: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4362: Channel *
1.367 djm 4363: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4364: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4365: {
1.367 djm 4366: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4367: struct permission_set *pset = &sc->local_perms;
1.372 markus 4368: struct channel_connect cctx;
4369: Channel *c;
1.367 djm 4370: u_int i, permit, permit_adm = 1;
1.372 markus 4371: int sock;
1.381 djm 4372: struct permission *perm;
1.99 markus 4373:
1.381 djm 4374: permit = pset->all_permitted;
1.99 markus 4375: if (!permit) {
1.381 djm 4376: for (i = 0; i < pset->num_permitted_user; i++) {
4377: perm = &pset->permitted_user[i];
4378: if (open_match(perm, host, port)) {
1.99 markus 4379: permit = 1;
1.333 markus 4380: break;
4381: }
1.367 djm 4382: }
1.257 dtucker 4383: }
1.99 markus 4384:
1.381 djm 4385: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4386: permit_adm = 0;
1.381 djm 4387: for (i = 0; i < pset->num_permitted_admin; i++) {
4388: perm = &pset->permitted_admin[i];
4389: if (open_match(perm, host, port)) {
1.257 dtucker 4390: permit_adm = 1;
1.333 markus 4391: break;
4392: }
1.367 djm 4393: }
1.99 markus 4394: }
1.257 dtucker 4395:
4396: if (!permit || !permit_adm) {
1.391 florian 4397: logit("Received request from %.100s port %d to connect to "
4398: "host %.100s port %d, but the request was denied.",
4399: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4400: if (reason != NULL)
4401: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4402: return NULL;
1.99 markus 4403: }
1.372 markus 4404:
4405: memset(&cctx, 0, sizeof(cctx));
4406: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4407: &cctx, reason, errmsg);
4408: if (sock == -1) {
4409: channel_connect_ctx_free(&cctx);
4410: return NULL;
4411: }
4412:
4413: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4414: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4415: c->host_port = port;
4416: c->path = xstrdup(host);
4417: c->connect_ctx = cctx;
4418:
4419: return c;
1.336 millert 4420: }
4421:
4422: /* Check if connecting to that path is permitted and connect. */
4423: Channel *
1.367 djm 4424: channel_connect_to_path(struct ssh *ssh, const char *path,
4425: char *ctype, char *rname)
1.336 millert 4426: {
1.367 djm 4427: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4428: struct permission_set *pset = &sc->local_perms;
1.367 djm 4429: u_int i, permit, permit_adm = 1;
1.381 djm 4430: struct permission *perm;
1.336 millert 4431:
1.381 djm 4432: permit = pset->all_permitted;
1.336 millert 4433: if (!permit) {
1.381 djm 4434: for (i = 0; i < pset->num_permitted_user; i++) {
4435: perm = &pset->permitted_user[i];
4436: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4437: permit = 1;
4438: break;
4439: }
1.367 djm 4440: }
1.336 millert 4441: }
4442:
1.381 djm 4443: if (pset->num_permitted_admin > 0) {
1.336 millert 4444: permit_adm = 0;
1.381 djm 4445: for (i = 0; i < pset->num_permitted_admin; i++) {
4446: perm = &pset->permitted_admin[i];
4447: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4448: permit_adm = 1;
4449: break;
4450: }
1.367 djm 4451: }
1.336 millert 4452: }
4453:
4454: if (!permit || !permit_adm) {
4455: logit("Received request to connect to path %.100s, "
4456: "but the request was denied.", path);
4457: return NULL;
4458: }
1.367 djm 4459: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4460: }
4461:
4462: void
1.367 djm 4463: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4464: {
1.367 djm 4465: struct ssh_channels *sc = ssh->chanctxt;
4466: struct winsize ws;
4467: int r;
1.209 avsm 4468: u_int i;
1.204 djm 4469:
1.367 djm 4470: for (i = 0; i < sc->channels_alloc; i++) {
4471: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4472: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4473: continue;
1.393 ! deraadt 4474: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4475: continue;
1.367 djm 4476: channel_request_start(ssh, i, "window-change", 0);
4477: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4478: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4479: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4480: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4481: (r = sshpkt_send(ssh)) != 0)
4482: fatal("%s: channel %u: send window-change: %s",
4483: __func__, i, ssh_err(r));
1.204 djm 4484: }
1.372 markus 4485: }
4486:
4487: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4488: static Channel *
4489: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4490: {
4491: Channel *c;
4492: int r;
4493:
4494: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4495: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4496: c->host_port = 0;
4497: c->path = NULL;
4498:
4499: /*
4500: * We need to open the channel before we have a FD,
4501: * so that we can get SOCKS header from peer.
4502: */
4503: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4504: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4505: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4506: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
4507: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
4508: fatal("%s: channel %i: confirm: %s", __func__,
4509: c->self, ssh_err(r));
4510: }
4511: return c;
4512: }
4513:
4514: /* Return CONNECTING socket to remote host:port or local socket path */
4515: static int
4516: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4517: {
4518: struct channel_connect cctx;
4519: int sock;
4520:
4521: memset(&cctx, 0, sizeof(cctx));
4522: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4523: NULL, &cctx, NULL, NULL);
4524: if (sock == -1)
4525: channel_connect_ctx_free(&cctx);
4526: else {
4527: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4528: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4529: c->connect_ctx = cctx;
4530: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4531: }
4532: return sock;
1.99 markus 4533: }
4534:
1.121 markus 4535: /* -- X11 forwarding */
1.1 deraadt 4536:
1.27 markus 4537: /*
4538: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4539: * Returns 0 and a suitable display number for the DISPLAY variable
4540: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4541: */
1.141 stevesk 4542: int
1.367 djm 4543: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4544: int x11_use_localhost, int single_connection,
4545: u_int *display_numberp, int **chanids)
1.1 deraadt 4546: {
1.149 markus 4547: Channel *nc = NULL;
1.31 markus 4548: int display_number, sock;
4549: u_short port;
1.35 markus 4550: struct addrinfo hints, *ai, *aitop;
4551: char strport[NI_MAXSERV];
4552: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4553:
1.224 markus 4554: if (chanids == NULL)
4555: return -1;
4556:
1.33 markus 4557: for (display_number = x11_display_offset;
1.148 deraadt 4558: display_number < MAX_DISPLAYS;
4559: display_number++) {
1.25 markus 4560: port = 6000 + display_number;
1.35 markus 4561: memset(&hints, 0, sizeof(hints));
1.367 djm 4562: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4563: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4564: hints.ai_socktype = SOCK_STREAM;
4565: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4566: if ((gaierr = getaddrinfo(NULL, strport,
4567: &hints, &aitop)) != 0) {
1.271 dtucker 4568: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4569: return -1;
1.25 markus 4570: }
1.35 markus 4571: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4572: if (ai->ai_family != AF_INET &&
4573: ai->ai_family != AF_INET6)
1.35 markus 4574: continue;
1.300 dtucker 4575: sock = socket(ai->ai_family, ai->ai_socktype,
4576: ai->ai_protocol);
1.393 ! deraadt 4577: if (sock == -1) {
1.35 markus 4578: error("socket: %.100s", strerror(errno));
1.203 markus 4579: freeaddrinfo(aitop);
1.141 stevesk 4580: return -1;
1.35 markus 4581: }
1.376 djm 4582: set_reuseaddr(sock);
1.393 ! deraadt 4583: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 4584: debug2("%s: bind port %d: %.100s", __func__,
4585: port, strerror(errno));
1.35 markus 4586: close(sock);
1.367 djm 4587: for (n = 0; n < num_socks; n++)
1.35 markus 4588: close(socks[n]);
4589: num_socks = 0;
4590: break;
4591: }
4592: socks[num_socks++] = sock;
4593: if (num_socks == NUM_SOCKS)
4594: break;
1.25 markus 4595: }
1.83 stevesk 4596: freeaddrinfo(aitop);
1.35 markus 4597: if (num_socks > 0)
4598: break;
1.25 markus 4599: }
4600: if (display_number >= MAX_DISPLAYS) {
4601: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4602: return -1;
1.25 markus 4603: }
4604: /* Start listening for connections on the socket. */
1.35 markus 4605: for (n = 0; n < num_socks; n++) {
4606: sock = socks[n];
1.393 ! deraadt 4607: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 4608: error("listen: %.100s", strerror(errno));
4609: close(sock);
1.141 stevesk 4610: return -1;
1.35 markus 4611: }
1.25 markus 4612: }
1.35 markus 4613:
4614: /* Allocate a channel for each socket. */
1.242 djm 4615: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4616: for (n = 0; n < num_socks; n++) {
4617: sock = socks[n];
1.367 djm 4618: nc = channel_new(ssh, "x11 listener",
1.51 markus 4619: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4620: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4621: 0, "X11 inet listener", 1);
1.167 markus 4622: nc->single_connection = single_connection;
1.224 markus 4623: (*chanids)[n] = nc->self;
1.35 markus 4624: }
1.224 markus 4625: (*chanids)[n] = -1;
1.1 deraadt 4626:
1.141 stevesk 4627: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4628: *display_numberp = display_number;
1.367 djm 4629: return 0;
1.1 deraadt 4630: }
4631:
1.127 itojun 4632: static int
1.77 markus 4633: connect_local_xsocket(u_int dnr)
1.1 deraadt 4634: {
1.25 markus 4635: int sock;
4636: struct sockaddr_un addr;
4637:
1.147 stevesk 4638: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 ! deraadt 4639: if (sock == -1)
1.147 stevesk 4640: error("socket: %.100s", strerror(errno));
4641: memset(&addr, 0, sizeof(addr));
4642: addr.sun_family = AF_UNIX;
4643: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4644: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4645: return sock;
4646: close(sock);
1.25 markus 4647: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4648: return -1;
1.1 deraadt 4649: }
4650:
1.51 markus 4651: int
1.367 djm 4652: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4653: {
1.248 deraadt 4654: u_int display_number;
1.25 markus 4655: const char *display;
1.51 markus 4656: char buf[1024], *cp;
1.35 markus 4657: struct addrinfo hints, *ai, *aitop;
4658: char strport[NI_MAXSERV];
1.248 deraadt 4659: int gaierr, sock = 0;
1.25 markus 4660:
4661: /* Try to open a socket for the local X server. */
4662: display = getenv("DISPLAY");
4663: if (!display) {
4664: error("DISPLAY not set.");
1.51 markus 4665: return -1;
1.25 markus 4666: }
1.27 markus 4667: /*
4668: * Now we decode the value of the DISPLAY variable and make a
4669: * connection to the real X server.
4670: */
4671:
4672: /*
4673: * Check if it is a unix domain socket. Unix domain displays are in
4674: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4675: */
1.25 markus 4676: if (strncmp(display, "unix:", 5) == 0 ||
4677: display[0] == ':') {
4678: /* Connect to the unix domain socket. */
1.367 djm 4679: if (sscanf(strrchr(display, ':') + 1, "%u",
4680: &display_number) != 1) {
4681: error("Could not parse display number from DISPLAY: "
4682: "%.100s", display);
1.51 markus 4683: return -1;
1.25 markus 4684: }
4685: /* Create a socket. */
4686: sock = connect_local_xsocket(display_number);
4687: if (sock < 0)
1.51 markus 4688: return -1;
1.25 markus 4689:
4690: /* OK, we now have a connection to the display. */
1.51 markus 4691: return sock;
1.25 markus 4692: }
1.27 markus 4693: /*
4694: * Connect to an inet socket. The DISPLAY value is supposedly
4695: * hostname:d[.s], where hostname may also be numeric IP address.
4696: */
1.145 stevesk 4697: strlcpy(buf, display, sizeof(buf));
1.25 markus 4698: cp = strchr(buf, ':');
4699: if (!cp) {
4700: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4701: return -1;
1.25 markus 4702: }
4703: *cp = 0;
1.367 djm 4704: /*
4705: * buf now contains the host name. But first we parse the
4706: * display number.
4707: */
1.248 deraadt 4708: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4709: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4710: display);
1.51 markus 4711: return -1;
1.25 markus 4712: }
1.35 markus 4713:
4714: /* Look up the host address */
4715: memset(&hints, 0, sizeof(hints));
1.367 djm 4716: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4717: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4718: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4719: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4720: error("%.100s: unknown host. (%s)", buf,
4721: ssh_gai_strerror(gaierr));
1.51 markus 4722: return -1;
1.25 markus 4723: }
1.35 markus 4724: for (ai = aitop; ai; ai = ai->ai_next) {
4725: /* Create a socket. */
1.300 dtucker 4726: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 ! deraadt 4727: if (sock == -1) {
1.194 markus 4728: debug2("socket: %.100s", strerror(errno));
1.41 markus 4729: continue;
4730: }
4731: /* Connect it to the display. */
1.393 ! deraadt 4732: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 4733: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4734: 6000 + display_number, strerror(errno));
4735: close(sock);
4736: continue;
4737: }
4738: /* Success */
4739: break;
1.35 markus 4740: }
4741: freeaddrinfo(aitop);
4742: if (!ai) {
1.367 djm 4743: error("connect %.100s port %u: %.100s", buf,
4744: 6000 + display_number, strerror(errno));
1.51 markus 4745: return -1;
1.25 markus 4746: }
1.162 stevesk 4747: set_nodelay(sock);
1.51 markus 4748: return sock;
4749: }
4750:
4751: /*
1.27 markus 4752: * Requests forwarding of X11 connections, generates fake authentication
4753: * data, and enables authentication spoofing.
1.121 markus 4754: * This should be called in the client only.
1.27 markus 4755: */
1.49 markus 4756: void
1.367 djm 4757: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4758: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4759: {
1.367 djm 4760: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4761: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4762: u_int i, value;
1.367 djm 4763: const char *cp;
1.25 markus 4764: char *new_data;
1.367 djm 4765: int r, screen_number;
1.25 markus 4766:
1.367 djm 4767: if (sc->x11_saved_display == NULL)
4768: sc->x11_saved_display = xstrdup(disp);
4769: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4770: error("x11_request_forwarding_with_spoofing: different "
4771: "$DISPLAY already forwarded");
4772: return;
4773: }
4774:
1.266 djm 4775: cp = strchr(disp, ':');
1.25 markus 4776: if (cp)
4777: cp = strchr(cp, '.');
4778: if (cp)
1.245 deraadt 4779: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4780: else
4781: screen_number = 0;
4782:
1.367 djm 4783: if (sc->x11_saved_proto == NULL) {
1.219 djm 4784: /* Save protocol name. */
1.367 djm 4785: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4786:
4787: /* Extract real authentication data. */
1.367 djm 4788: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4789: for (i = 0; i < data_len; i++) {
4790: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4791: fatal("x11_request_forwarding: bad "
4792: "authentication data: %.100s", data);
1.367 djm 4793: sc->x11_saved_data[i] = value;
1.219 djm 4794: }
1.367 djm 4795: sc->x11_saved_data_len = data_len;
1.353 natano 4796:
4797: /* Generate fake data of the same length. */
1.367 djm 4798: sc->x11_fake_data = xmalloc(data_len);
4799: arc4random_buf(sc->x11_fake_data, data_len);
4800: sc->x11_fake_data_len = data_len;
1.25 markus 4801: }
4802:
4803: /* Convert the fake data into hex. */
1.367 djm 4804: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 4805:
4806: /* Send the request packet. */
1.367 djm 4807: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4808: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4809: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4810: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4811: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4812: (r = sshpkt_send(ssh)) != 0 ||
4813: (r = ssh_packet_write_wait(ssh)) != 0)
4814: fatal("%s: send x11-req: %s", __func__, ssh_err(r));
1.321 djm 4815: free(new_data);
1.1 deraadt 4816: }
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