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