Annotation of src/usr.bin/ssh/channels.c, Revision 1.386
1.386 ! djm 1: /* $OpenBSD: channels.c,v 1.385 2018/10/04 00:10:11 djm Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.336 millert 43: #include <sys/stat.h>
1.234 stevesk 44: #include <sys/ioctl.h>
1.235 stevesk 45: #include <sys/un.h>
1.251 stevesk 46: #include <sys/socket.h>
1.261 stevesk 47: #include <sys/time.h>
1.275 djm 48: #include <sys/queue.h>
1.251 stevesk 49:
50: #include <netinet/in.h>
51: #include <arpa/inet.h>
1.233 stevesk 52:
1.254 stevesk 53: #include <errno.h>
1.298 dtucker 54: #include <fcntl.h>
1.367 djm 55: #include <limits.h>
1.255 stevesk 56: #include <netdb.h>
1.367 djm 57: #include <stdarg.h>
1.341 millert 58: #include <stdint.h>
1.263 stevesk 59: #include <stdio.h>
1.262 stevesk 60: #include <stdlib.h>
1.260 stevesk 61: #include <string.h>
1.233 stevesk 62: #include <termios.h>
1.256 stevesk 63: #include <unistd.h>
1.1 deraadt 64:
1.265 deraadt 65: #include "xmalloc.h"
1.1 deraadt 66: #include "ssh.h"
1.82 markus 67: #include "ssh2.h"
1.354 markus 68: #include "ssherr.h"
1.367 djm 69: #include "sshbuf.h"
1.1 deraadt 70: #include "packet.h"
1.82 markus 71: #include "log.h"
72: #include "misc.h"
1.14 markus 73: #include "channels.h"
74: #include "compat.h"
1.82 markus 75: #include "canohost.h"
1.383 markus 76: #include "sshkey.h"
1.64 markus 77: #include "authfd.h"
1.147 stevesk 78: #include "pathnames.h"
1.381 djm 79: #include "match.h"
1.1 deraadt 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:
224: if ((sc = calloc(1, sizeof(*sc))) == NULL ||
225: (sc->channel_pre = calloc(SSH_CHANNEL_MAX_TYPE,
226: sizeof(*sc->channel_pre))) == NULL ||
227: (sc->channel_post = calloc(SSH_CHANNEL_MAX_TYPE,
228: sizeof(*sc->channel_post))) == NULL)
229: fatal("%s: allocation failed", __func__);
230: sc->channels_alloc = 10;
231: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
232: sc->IPv4or6 = AF_UNSPEC;
233: channel_handler_init(sc);
234:
235: ssh->chanctxt = sc;
236: }
237:
1.41 markus 238: Channel *
1.367 djm 239: channel_by_id(struct ssh *ssh, int id)
1.41 markus 240: {
241: Channel *c;
1.113 markus 242:
1.367 djm 243: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
244: logit("%s: %d: bad id", __func__, id);
1.41 markus 245: return NULL;
246: }
1.367 djm 247: c = ssh->chanctxt->channels[id];
1.113 markus 248: if (c == NULL) {
1.367 djm 249: logit("%s: %d: bad id: channel free", __func__, id);
1.41 markus 250: return NULL;
251: }
252: return c;
1.55 markus 253: }
254:
1.354 markus 255: Channel *
1.368 djm 256: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 257: {
258: Channel *c;
259: u_int i;
260:
1.367 djm 261: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
262: c = ssh->chanctxt->channels[i];
1.368 djm 263: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 264: return c;
265: }
266: return NULL;
267: }
268:
1.27 markus 269: /*
1.229 markus 270: * Returns the channel if it is allowed to receive protocol messages.
271: * Private channels, like listening sockets, may not receive messages.
272: */
273: Channel *
1.367 djm 274: channel_lookup(struct ssh *ssh, int id)
1.229 markus 275: {
276: Channel *c;
277:
1.367 djm 278: if ((c = channel_by_id(ssh, id)) == NULL)
279: return NULL;
1.229 markus 280:
1.237 deraadt 281: switch (c->type) {
1.229 markus 282: case SSH_CHANNEL_X11_OPEN:
283: case SSH_CHANNEL_LARVAL:
284: case SSH_CHANNEL_CONNECTING:
285: case SSH_CHANNEL_DYNAMIC:
1.372 markus 286: case SSH_CHANNEL_RDYNAMIC_OPEN:
287: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 288: case SSH_CHANNEL_OPENING:
289: case SSH_CHANNEL_OPEN:
1.323 dtucker 290: case SSH_CHANNEL_ABANDONED:
1.354 markus 291: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 292: return c;
1.229 markus 293: }
294: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 295: return NULL;
1.229 markus 296: }
297:
298: /*
1.55 markus 299: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 300: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 301: */
1.127 itojun 302: static void
1.367 djm 303: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 304: int extusage, int nonblock, int is_tty)
1.1 deraadt 305: {
1.367 djm 306: struct ssh_channels *sc = ssh->chanctxt;
307:
1.25 markus 308: /* Update the maximum file descriptor value. */
1.367 djm 309: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, rfd);
310: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, wfd);
311: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, efd);
1.84 markus 312:
1.298 dtucker 313: if (rfd != -1)
314: fcntl(rfd, F_SETFD, FD_CLOEXEC);
315: if (wfd != -1 && wfd != rfd)
316: fcntl(wfd, F_SETFD, FD_CLOEXEC);
317: if (efd != -1 && efd != rfd && efd != wfd)
318: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 319:
1.52 markus 320: c->rfd = rfd;
321: c->wfd = wfd;
322: c->sock = (rfd == wfd) ? rfd : -1;
323: c->efd = efd;
324: c->extended_usage = extusage;
1.71 markus 325:
1.282 dtucker 326: if ((c->isatty = is_tty) != 0)
1.194 markus 327: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 328:
1.71 markus 329: /* enable nonblocking mode */
330: if (nonblock) {
331: if (rfd != -1)
332: set_nonblock(rfd);
333: if (wfd != -1)
334: set_nonblock(wfd);
335: if (efd != -1)
336: set_nonblock(efd);
337: }
1.52 markus 338: }
339:
340: /*
341: * Allocate a new channel object and set its type and socket. This will cause
342: * remote_name to be freed.
343: */
1.113 markus 344: Channel *
1.367 djm 345: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 346: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 347: {
1.367 djm 348: struct ssh_channels *sc = ssh->chanctxt;
349: u_int i, found;
1.52 markus 350: Channel *c;
1.25 markus 351:
352: /* Try to find a free slot where to put the new channel. */
1.367 djm 353: for (i = 0; i < sc->channels_alloc; i++) {
354: if (sc->channels[i] == NULL) {
1.25 markus 355: /* Found a free slot. */
1.367 djm 356: found = i;
1.25 markus 357: break;
358: }
1.367 djm 359: }
360: if (i >= sc->channels_alloc) {
361: /*
362: * There are no free slots. Take last+1 slot and expand
363: * the array.
364: */
365: found = sc->channels_alloc;
366: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
367: fatal("%s: internal error: channels_alloc %d too big",
368: __func__, sc->channels_alloc);
369: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
370: sc->channels_alloc + 10, sizeof(*sc->channels));
371: sc->channels_alloc += 10;
372: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 373: }
1.113 markus 374: /* Initialize and return new channel. */
1.367 djm 375: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
376: if ((c->input = sshbuf_new()) == NULL ||
377: (c->output = sshbuf_new()) == NULL ||
378: (c->extended = sshbuf_new()) == NULL)
379: fatal("%s: sshbuf_new failed", __func__);
1.159 markus 380: c->ostate = CHAN_OUTPUT_OPEN;
381: c->istate = CHAN_INPUT_OPEN;
1.367 djm 382: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 383: c->self = found;
384: c->type = type;
1.41 markus 385: c->ctype = ctype;
1.51 markus 386: c->local_window = window;
387: c->local_window_max = window;
388: c->local_maxpacket = maxpack;
1.190 markus 389: c->remote_name = xstrdup(remote_name);
1.302 djm 390: c->ctl_chan = -1;
1.299 markus 391: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 392: TAILQ_INIT(&c->status_confirms);
1.25 markus 393: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 394: return c;
1.1 deraadt 395: }
1.52 markus 396:
1.367 djm 397: static void
398: channel_find_maxfd(struct ssh_channels *sc)
1.132 markus 399: {
1.209 avsm 400: u_int i;
401: int max = 0;
1.132 markus 402: Channel *c;
403:
1.367 djm 404: for (i = 0; i < sc->channels_alloc; i++) {
405: c = sc->channels[i];
1.132 markus 406: if (c != NULL) {
1.352 deraadt 407: max = MAXIMUM(max, c->rfd);
408: max = MAXIMUM(max, c->wfd);
409: max = MAXIMUM(max, c->efd);
1.132 markus 410: }
411: }
1.367 djm 412: sc->channel_max_fd = max;
1.132 markus 413: }
414:
415: int
1.367 djm 416: channel_close_fd(struct ssh *ssh, int *fdp)
1.132 markus 417: {
1.367 djm 418: struct ssh_channels *sc = ssh->chanctxt;
1.132 markus 419: int ret = 0, fd = *fdp;
420:
421: if (fd != -1) {
422: ret = close(fd);
423: *fdp = -1;
1.367 djm 424: if (fd == sc->channel_max_fd)
425: channel_find_maxfd(sc);
1.132 markus 426: }
427: return ret;
428: }
429:
1.52 markus 430: /* Close all channel fd/socket. */
1.127 itojun 431: static void
1.367 djm 432: channel_close_fds(struct ssh *ssh, Channel *c)
433: {
1.379 tb 434: int sock = c->sock, rfd = c->rfd, wfd = c->wfd, efd = c->efd;
435:
1.367 djm 436: channel_close_fd(ssh, &c->sock);
1.379 tb 437: if (rfd != sock)
438: channel_close_fd(ssh, &c->rfd);
439: if (wfd != sock && wfd != rfd)
440: channel_close_fd(ssh, &c->wfd);
441: if (efd != sock && efd != rfd && efd != wfd)
442: channel_close_fd(ssh, &c->efd);
1.367 djm 443: }
444:
445: static void
1.381 djm 446: fwd_perm_clear(struct permission *perm)
1.52 markus 447: {
1.381 djm 448: free(perm->host_to_connect);
449: free(perm->listen_host);
450: free(perm->listen_path);
451: bzero(perm, sizeof(*perm));
1.367 djm 452: }
453:
1.381 djm 454: /* Returns an printable name for the specified forwarding permission list */
455: static const char *
456: fwd_ident(int who, int where)
457: {
458: if (who == FORWARD_ADM) {
459: if (where == FORWARD_LOCAL)
460: return "admin local";
461: else if (where == FORWARD_REMOTE)
462: return "admin remote";
463: } else if (who == FORWARD_USER) {
464: if (where == FORWARD_LOCAL)
465: return "user local";
466: else if (where == FORWARD_REMOTE)
467: return "user remote";
468: }
469: fatal("Unknown forward permission list %d/%d", who, where);
470: }
471:
472: /* Returns the forwarding permission list for the specified direction */
473: static struct permission_set *
474: permission_set_get(struct ssh *ssh, int where)
475: {
476: struct ssh_channels *sc = ssh->chanctxt;
1.367 djm 477:
1.381 djm 478: switch (where) {
479: case FORWARD_LOCAL:
480: return &sc->local_perms;
481: break;
482: case FORWARD_REMOTE:
483: return &sc->remote_perms;
484: break;
485: default:
486: fatal("%s: invalid forwarding direction %d", __func__, where);
487: }
488: }
489:
490: /* Reutrns pointers to the specified forwarding list and its element count */
491: static void
492: permission_set_get_array(struct ssh *ssh, int who, int where,
493: struct permission ***permpp, u_int **npermpp)
494: {
495: struct permission_set *pset = permission_set_get(ssh, where);
496:
497: switch (who) {
498: case FORWARD_USER:
499: *permpp = &pset->permitted_user;
500: *npermpp = &pset->num_permitted_user;
501: break;
502: case FORWARD_ADM:
503: *permpp = &pset->permitted_admin;
504: *npermpp = &pset->num_permitted_admin;
505: break;
506: default:
507: fatal("%s: invalid forwarding client %d", __func__, who);
508: }
509: }
510:
511: /* Adds an entry to the spcified forwarding list */
1.367 djm 512: static int
1.381 djm 513: permission_set_add(struct ssh *ssh, int who, int where,
1.367 djm 514: const char *host_to_connect, int port_to_connect,
515: const char *listen_host, const char *listen_path, int listen_port,
516: Channel *downstream)
517: {
1.381 djm 518: struct permission **permp;
519: u_int n, *npermp;
1.367 djm 520:
1.381 djm 521: permission_set_get_array(ssh, who, where, &permp, &npermp);
1.367 djm 522:
1.381 djm 523: if (*npermp >= INT_MAX)
524: fatal("%s: %s overflow", __func__, fwd_ident(who, where));
1.367 djm 525:
1.381 djm 526: *permp = xrecallocarray(*permp, *npermp, *npermp + 1, sizeof(**permp));
527: n = (*npermp)++;
1.367 djm 528: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
1.381 djm 529: (*permp)[n].host_to_connect = MAYBE_DUP(host_to_connect);
530: (*permp)[n].port_to_connect = port_to_connect;
531: (*permp)[n].listen_host = MAYBE_DUP(listen_host);
532: (*permp)[n].listen_path = MAYBE_DUP(listen_path);
533: (*permp)[n].listen_port = listen_port;
534: (*permp)[n].downstream = downstream;
1.367 djm 535: #undef MAYBE_DUP
536: return (int)n;
537: }
538:
539: static void
540: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
541: {
542: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 543: struct permission_set *pset = &sc->local_perms;
544: struct permission *perm;
1.367 djm 545: int r;
546: u_int i;
547:
1.381 djm 548: for (i = 0; i < pset->num_permitted_user; i++) {
549: perm = &pset->permitted_user[i];
550: if (perm->downstream != c)
1.367 djm 551: continue;
552:
553: /* cancel on the server, since mux client is gone */
554: debug("channel %d: cleanup remote forward for %s:%u",
1.381 djm 555: c->self, perm->listen_host, perm->listen_port);
1.367 djm 556: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
557: (r = sshpkt_put_cstring(ssh,
558: "cancel-tcpip-forward")) != 0 ||
559: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
560: (r = sshpkt_put_cstring(ssh,
1.381 djm 561: channel_rfwd_bind_host(perm->listen_host))) != 0 ||
562: (r = sshpkt_put_u32(ssh, perm->listen_port)) != 0 ||
1.367 djm 563: (r = sshpkt_send(ssh)) != 0) {
564: fatal("%s: channel %i: %s", __func__,
565: c->self, ssh_err(r));
566: }
1.381 djm 567: fwd_perm_clear(perm); /* unregister */
1.367 djm 568: }
1.121 markus 569: }
570:
571: /* Free the channel and close its fd/socket. */
572: void
1.367 djm 573: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 574: {
1.367 djm 575: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 576: char *s;
1.209 avsm 577: u_int i, n;
1.354 markus 578: Channel *other;
1.275 djm 579: struct channel_confirm *cc;
1.121 markus 580:
1.367 djm 581: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
582: if ((other = sc->channels[i]) == NULL)
583: continue;
584: n++;
585: /* detach from mux client and prepare for closing */
586: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
587: other->type == SSH_CHANNEL_MUX_PROXY &&
588: other->mux_ctx == c) {
589: other->mux_ctx = NULL;
590: other->type = SSH_CHANNEL_OPEN;
591: other->istate = CHAN_INPUT_CLOSED;
592: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 593: }
594: }
1.209 avsm 595: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 596: c->remote_name ? c->remote_name : "???", n);
597:
1.367 djm 598: if (c->type == SSH_CHANNEL_MUX_CLIENT)
599: mux_remove_remote_forwardings(ssh, c);
1.354 markus 600:
1.384 markus 601: if (log_level_get() >= SYSLOG_LEVEL_DEBUG3) {
602: s = channel_open_message(ssh);
603: debug3("channel %d: status: %s", c->self, s);
604: free(s);
605: }
1.121 markus 606:
1.367 djm 607: channel_close_fds(ssh, c);
608: sshbuf_free(c->input);
609: sshbuf_free(c->output);
610: sshbuf_free(c->extended);
611: c->input = c->output = c->extended = NULL;
1.321 djm 612: free(c->remote_name);
613: c->remote_name = NULL;
614: free(c->path);
615: c->path = NULL;
616: free(c->listening_addr);
617: c->listening_addr = NULL;
1.275 djm 618: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
619: if (cc->abandon_cb != NULL)
1.367 djm 620: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 621: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 622: explicit_bzero(cc, sizeof(*cc));
1.321 djm 623: free(cc);
1.275 djm 624: }
1.280 djm 625: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 626: c->filter_cleanup(ssh, c->self, c->filter_ctx);
627: sc->channels[c->self] = NULL;
1.371 millert 628: explicit_bzero(c, sizeof(*c));
1.321 djm 629: free(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;
1.121 markus 636:
1.367 djm 637: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
638: if (ssh->chanctxt->channels[i] != NULL)
639: channel_free(ssh, ssh->chanctxt->channels[i]);
1.131 markus 640: }
641:
1.121 markus 642: /*
643: * Closes the sockets/fds of all channels. This is used to close extra file
644: * descriptors after a fork.
645: */
646: void
1.367 djm 647: channel_close_all(struct ssh *ssh)
1.121 markus 648: {
1.209 avsm 649: u_int i;
1.121 markus 650:
1.367 djm 651: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
652: if (ssh->chanctxt->channels[i] != NULL)
653: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 654: }
655:
656: /*
1.131 markus 657: * Stop listening to channels.
658: */
659: void
1.367 djm 660: channel_stop_listening(struct ssh *ssh)
1.131 markus 661: {
1.209 avsm 662: u_int i;
1.131 markus 663: Channel *c;
664:
1.367 djm 665: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
666: c = ssh->chanctxt->channels[i];
1.131 markus 667: if (c != NULL) {
668: switch (c->type) {
669: case SSH_CHANNEL_AUTH_SOCKET:
670: case SSH_CHANNEL_PORT_LISTENER:
671: case SSH_CHANNEL_RPORT_LISTENER:
672: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 673: case SSH_CHANNEL_UNIX_LISTENER:
674: case SSH_CHANNEL_RUNIX_LISTENER:
1.367 djm 675: channel_close_fd(ssh, &c->sock);
676: channel_free(ssh, c);
1.131 markus 677: break;
678: }
679: }
680: }
681: }
682:
683: /*
1.121 markus 684: * Returns true if no channel has too much buffered data, and false if one or
685: * more channel is overfull.
686: */
687: int
1.367 djm 688: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 689: {
690: u_int i;
1.367 djm 691: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 692: Channel *c;
693:
1.367 djm 694: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
695: c = ssh->chanctxt->channels[i];
696: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
697: continue;
698: if (sshbuf_len(c->output) > maxsize) {
699: debug2("channel %d: big output buffer %zu > %u",
700: c->self, sshbuf_len(c->output), maxsize);
701: return 0;
1.121 markus 702: }
703: }
704: return 1;
705: }
706:
707: /* Returns true if any channel is still open. */
708: int
1.367 djm 709: channel_still_open(struct ssh *ssh)
1.121 markus 710: {
1.209 avsm 711: u_int i;
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];
1.121 markus 716: if (c == NULL)
717: continue;
718: switch (c->type) {
719: case SSH_CHANNEL_X11_LISTENER:
720: case SSH_CHANNEL_PORT_LISTENER:
721: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 722: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 723: case SSH_CHANNEL_CLOSED:
724: case SSH_CHANNEL_AUTH_SOCKET:
725: case SSH_CHANNEL_DYNAMIC:
1.372 markus 726: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 727: case SSH_CHANNEL_CONNECTING:
728: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 729: case SSH_CHANNEL_ABANDONED:
1.336 millert 730: case SSH_CHANNEL_UNIX_LISTENER:
731: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 732: continue;
733: case SSH_CHANNEL_LARVAL:
734: continue;
735: case SSH_CHANNEL_OPENING:
736: case SSH_CHANNEL_OPEN:
1.372 markus 737: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 738: case SSH_CHANNEL_X11_OPEN:
1.302 djm 739: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 740: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 741: return 1;
742: default:
1.358 djm 743: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 744: /* NOTREACHED */
745: }
746: }
747: return 0;
748: }
749:
750: /* Returns the id of an open channel suitable for keepaliving */
751: int
1.367 djm 752: channel_find_open(struct ssh *ssh)
1.121 markus 753: {
1.209 avsm 754: u_int i;
1.121 markus 755: Channel *c;
756:
1.367 djm 757: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
758: c = ssh->chanctxt->channels[i];
1.368 djm 759: if (c == NULL || !c->have_remote_id)
1.121 markus 760: continue;
761: switch (c->type) {
762: case SSH_CHANNEL_CLOSED:
763: case SSH_CHANNEL_DYNAMIC:
1.372 markus 764: case SSH_CHANNEL_RDYNAMIC_OPEN:
765: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 766: case SSH_CHANNEL_X11_LISTENER:
767: case SSH_CHANNEL_PORT_LISTENER:
768: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 769: case SSH_CHANNEL_MUX_LISTENER:
770: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 771: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 772: case SSH_CHANNEL_OPENING:
773: case SSH_CHANNEL_CONNECTING:
774: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 775: case SSH_CHANNEL_ABANDONED:
1.336 millert 776: case SSH_CHANNEL_UNIX_LISTENER:
777: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 778: continue;
779: case SSH_CHANNEL_LARVAL:
780: case SSH_CHANNEL_AUTH_SOCKET:
781: case SSH_CHANNEL_OPEN:
782: case SSH_CHANNEL_X11_OPEN:
783: return i;
784: default:
1.358 djm 785: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 786: /* NOTREACHED */
787: }
788: }
789: return -1;
790: }
791:
1.385 djm 792: /* Returns the state of the channel's extended usage flag */
793: const char *
794: channel_format_extended_usage(const Channel *c)
795: {
796: if (c->efd == -1)
797: return "closed";
798:
799: switch (c->extended_usage) {
800: case CHAN_EXTENDED_WRITE:
801: return "write";
802: case CHAN_EXTENDED_READ:
803: return "read";
804: case CHAN_EXTENDED_IGNORE:
805: return "ignore";
806: default:
807: return "UNKNOWN";
808: }
809: }
810:
1.386 ! djm 811: static char *
! 812: channel_format_status(const Channel *c)
! 813: {
! 814: char *ret = NULL;
! 815:
! 816: xasprintf(&ret, "t%d %s%u i%u/%zu o%u/%zu e[%s]/%zu "
! 817: "fd %d/%d/%d sock %d cc %d",
! 818: c->type,
! 819: c->have_remote_id ? "r" : "nr", c->remote_id,
! 820: c->istate, sshbuf_len(c->input),
! 821: c->ostate, sshbuf_len(c->output),
! 822: channel_format_extended_usage(c), sshbuf_len(c->extended),
! 823: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan);
! 824: return ret;
! 825: }
! 826:
1.121 markus 827: /*
828: * Returns a message describing the currently open forwarded connections,
829: * suitable for sending to the client. The message contains crlf pairs for
830: * newlines.
831: */
832: char *
1.367 djm 833: channel_open_message(struct ssh *ssh)
1.121 markus 834: {
1.367 djm 835: struct sshbuf *buf;
1.121 markus 836: Channel *c;
1.209 avsm 837: u_int i;
1.367 djm 838: int r;
1.386 ! djm 839: char *cp, *ret;
1.121 markus 840:
1.367 djm 841: if ((buf = sshbuf_new()) == NULL)
842: fatal("%s: sshbuf_new", __func__);
843: if ((r = sshbuf_putf(buf,
844: "The following connections are open:\r\n")) != 0)
845: fatal("%s: sshbuf_putf: %s", __func__, ssh_err(r));
846: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
847: c = ssh->chanctxt->channels[i];
1.121 markus 848: if (c == NULL)
849: continue;
850: switch (c->type) {
851: case SSH_CHANNEL_X11_LISTENER:
852: case SSH_CHANNEL_PORT_LISTENER:
853: case SSH_CHANNEL_RPORT_LISTENER:
854: case SSH_CHANNEL_CLOSED:
855: case SSH_CHANNEL_AUTH_SOCKET:
856: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 857: case SSH_CHANNEL_ABANDONED:
1.302 djm 858: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 859: case SSH_CHANNEL_UNIX_LISTENER:
860: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 861: continue;
862: case SSH_CHANNEL_LARVAL:
863: case SSH_CHANNEL_OPENING:
864: case SSH_CHANNEL_CONNECTING:
865: case SSH_CHANNEL_DYNAMIC:
1.372 markus 866: case SSH_CHANNEL_RDYNAMIC_OPEN:
867: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 868: case SSH_CHANNEL_OPEN:
869: case SSH_CHANNEL_X11_OPEN:
1.354 markus 870: case SSH_CHANNEL_MUX_PROXY:
871: case SSH_CHANNEL_MUX_CLIENT:
1.386 ! djm 872: cp = channel_format_status(c);
! 873: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
! 874: c->self, c->remote_name, cp)) != 0) {
! 875: free(cp);
1.367 djm 876: fatal("%s: sshbuf_putf: %s",
877: __func__, ssh_err(r));
1.386 ! djm 878: }
! 879: free(cp);
1.121 markus 880: continue;
881: default:
1.367 djm 882: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 883: /* NOTREACHED */
884: }
885: }
1.367 djm 886: if ((ret = sshbuf_dup_string(buf)) == NULL)
887: fatal("%s: sshbuf_dup_string", __func__);
888: sshbuf_free(buf);
889: return ret;
890: }
891:
892: static void
893: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
894: {
895: int r;
896:
897: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
898: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
899: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
900: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
901: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
902: fatal("%s: channel %i: open: %s", where, c->self, ssh_err(r));
903: }
1.121 markus 904: }
905:
906: void
1.367 djm 907: channel_send_open(struct ssh *ssh, int id)
1.121 markus 908: {
1.367 djm 909: Channel *c = channel_lookup(ssh, id);
910: int r;
1.180 deraadt 911:
1.121 markus 912: if (c == NULL) {
1.188 itojun 913: logit("channel_send_open: %d: bad id", id);
1.121 markus 914: return;
915: }
1.184 markus 916: debug2("channel %d: send open", id);
1.367 djm 917: open_preamble(ssh, __func__, c, c->ctype);
918: if ((r = sshpkt_send(ssh)) != 0)
919: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.121 markus 920: }
921:
922: void
1.367 djm 923: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 924: {
1.367 djm 925: Channel *c = channel_lookup(ssh, id);
926: int r;
1.180 deraadt 927:
1.121 markus 928: if (c == NULL) {
1.367 djm 929: logit("%s: %d: unknown channel id", __func__, id);
1.121 markus 930: return;
931: }
1.368 djm 932: if (!c->have_remote_id)
933: fatal(":%s: channel %d: no remote id", __func__, c->self);
934:
1.204 djm 935: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 936: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
937: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
938: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
939: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
940: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
941: }
1.121 markus 942: }
1.241 deraadt 943:
1.121 markus 944: void
1.367 djm 945: channel_register_status_confirm(struct ssh *ssh, int id,
946: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 947: {
948: struct channel_confirm *cc;
949: Channel *c;
950:
1.367 djm 951: if ((c = channel_lookup(ssh, id)) == NULL)
952: fatal("%s: %d: bad id", __func__, id);
1.275 djm 953:
1.327 djm 954: cc = xcalloc(1, sizeof(*cc));
1.275 djm 955: cc->cb = cb;
956: cc->abandon_cb = abandon_cb;
957: cc->ctx = ctx;
958: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
959: }
960:
961: void
1.367 djm 962: channel_register_open_confirm(struct ssh *ssh, int id,
963: channel_open_fn *fn, void *ctx)
1.121 markus 964: {
1.367 djm 965: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 966:
1.121 markus 967: if (c == NULL) {
1.367 djm 968: logit("%s: %d: bad id", __func__, id);
1.121 markus 969: return;
970: }
1.275 djm 971: c->open_confirm = fn;
972: c->open_confirm_ctx = ctx;
1.121 markus 973: }
1.241 deraadt 974:
1.121 markus 975: void
1.367 djm 976: channel_register_cleanup(struct ssh *ssh, int id,
977: channel_callback_fn *fn, int do_close)
1.121 markus 978: {
1.367 djm 979: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 980:
1.121 markus 981: if (c == NULL) {
1.367 djm 982: logit("%s: %d: bad id", __func__, id);
1.121 markus 983: return;
984: }
1.131 markus 985: c->detach_user = fn;
1.225 djm 986: c->detach_close = do_close;
1.121 markus 987: }
1.241 deraadt 988:
1.121 markus 989: void
1.367 djm 990: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 991: {
1.367 djm 992: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 993:
1.121 markus 994: if (c == NULL) {
1.367 djm 995: logit("%s: %d: bad id", __func__, id);
1.121 markus 996: return;
1.52 markus 997: }
1.131 markus 998: c->detach_user = NULL;
1.225 djm 999: c->detach_close = 0;
1.121 markus 1000: }
1.241 deraadt 1001:
1.121 markus 1002: void
1.367 djm 1003: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1004: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1005: {
1.367 djm 1006: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1007:
1.121 markus 1008: if (c == NULL) {
1.367 djm 1009: logit("%s: %d: bad id", __func__, id);
1.121 markus 1010: return;
1.52 markus 1011: }
1.231 reyk 1012: c->input_filter = ifn;
1013: c->output_filter = ofn;
1.279 djm 1014: c->filter_ctx = ctx;
1.280 djm 1015: c->filter_cleanup = cfn;
1.52 markus 1016: }
1017:
1.49 markus 1018: void
1.367 djm 1019: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1020: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1021: {
1.367 djm 1022: Channel *c = channel_lookup(ssh, id);
1023: int r;
1.180 deraadt 1024:
1.121 markus 1025: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1026: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1027: if (!c->have_remote_id)
1028: fatal(":%s: channel %d: no remote id", __func__, c->self);
1029:
1.367 djm 1030: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1031: c->type = SSH_CHANNEL_OPEN;
1.168 markus 1032: c->local_window = c->local_window_max = window_max;
1.367 djm 1033:
1034: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1035: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1036: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1037: (r = sshpkt_send(ssh)) != 0)
1038: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.1 deraadt 1039: }
1040:
1.127 itojun 1041: static void
1.367 djm 1042: channel_pre_listener(struct ssh *ssh, Channel *c,
1043: fd_set *readset, fd_set *writeset)
1.41 markus 1044: {
1045: FD_SET(c->sock, readset);
1046: }
1047:
1.127 itojun 1048: static void
1.367 djm 1049: channel_pre_connecting(struct ssh *ssh, Channel *c,
1050: fd_set *readset, fd_set *writeset)
1.75 markus 1051: {
1052: debug3("channel %d: waiting for connection", c->self);
1053: FD_SET(c->sock, writeset);
1054: }
1055:
1.127 itojun 1056: static void
1.367 djm 1057: channel_pre_open(struct ssh *ssh, Channel *c,
1058: fd_set *readset, fd_set *writeset)
1.41 markus 1059: {
1.44 markus 1060: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1061: c->remote_window > 0 &&
1.367 djm 1062: sshbuf_len(c->input) < c->remote_window &&
1063: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.44 markus 1064: FD_SET(c->rfd, readset);
1065: if (c->ostate == CHAN_OUTPUT_OPEN ||
1066: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1067: if (sshbuf_len(c->output) > 0) {
1.44 markus 1068: FD_SET(c->wfd, writeset);
1069: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1070: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1071: debug2("channel %d: "
1072: "obuf_empty delayed efd %d/(%zu)", c->self,
1073: c->efd, sshbuf_len(c->extended));
1.172 markus 1074: else
1.367 djm 1075: chan_obuf_empty(ssh, c);
1.44 markus 1076: }
1077: }
1078: /** XXX check close conditions, too */
1.358 djm 1079: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1080: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1081: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1082: sshbuf_len(c->extended) > 0)
1.44 markus 1083: FD_SET(c->efd, writeset);
1.306 djm 1084: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1085: (c->extended_usage == CHAN_EXTENDED_READ ||
1086: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1087: sshbuf_len(c->extended) < c->remote_window)
1.44 markus 1088: FD_SET(c->efd, readset);
1089: }
1.204 djm 1090: /* XXX: What about efd? races? */
1.44 markus 1091: }
1092:
1.41 markus 1093: /*
1094: * This is a special state for X11 authentication spoofing. An opened X11
1095: * connection (when authentication spoofing is being done) remains in this
1096: * state until the first packet has been completely read. The authentication
1097: * data in that packet is then substituted by the real data if it matches the
1098: * fake data, and the channel is put into normal mode.
1.51 markus 1099: * XXX All this happens at the client side.
1.121 markus 1100: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1101: */
1.127 itojun 1102: static int
1.367 djm 1103: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1104: {
1.367 djm 1105: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1106: u_char *ucp;
1107: u_int proto_len, data_len;
1.25 markus 1108:
1.347 djm 1109: /* Is this being called after the refusal deadline? */
1.367 djm 1110: if (sc->x11_refuse_time != 0 &&
1111: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1112: verbose("Rejected X11 connection after ForwardX11Timeout "
1113: "expired");
1114: return -1;
1115: }
1116:
1.41 markus 1117: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1118: if (sshbuf_len(b) < 12)
1.41 markus 1119: return 0;
1120:
1121: /* Parse the lengths of variable-length fields. */
1.367 djm 1122: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1123: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1124: proto_len = 256 * ucp[6] + ucp[7];
1125: data_len = 256 * ucp[8] + ucp[9];
1126: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1127: proto_len = ucp[6] + 256 * ucp[7];
1128: data_len = ucp[8] + 256 * ucp[9];
1129: } else {
1.194 markus 1130: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1131: ucp[0]);
1.41 markus 1132: return -1;
1133: }
1134:
1135: /* Check if the whole packet is in buffer. */
1.367 djm 1136: if (sshbuf_len(b) <
1.41 markus 1137: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1138: return 0;
1139:
1140: /* Check if authentication protocol matches. */
1.367 djm 1141: if (proto_len != strlen(sc->x11_saved_proto) ||
1142: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1143: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1144: return -1;
1145: }
1146: /* Check if authentication data matches our fake data. */
1.367 djm 1147: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1148: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1149: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1150: debug2("X11 auth data does not match fake data.");
1.41 markus 1151: return -1;
1152: }
1153: /* Check fake data length */
1.367 djm 1154: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1155: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1156: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1157: return -1;
1158: }
1159: /*
1160: * Received authentication protocol and data match
1161: * our fake data. Substitute the fake data with real
1162: * data.
1163: */
1164: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1165: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1166: return 1;
1167: }
1168:
1.127 itojun 1169: static void
1.367 djm 1170: channel_pre_x11_open(struct ssh *ssh, Channel *c,
1171: fd_set *readset, fd_set *writeset)
1.41 markus 1172: {
1.367 djm 1173: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1174:
1175: /* c->force_drain = 1; */
1176:
1.41 markus 1177: if (ret == 1) {
1178: c->type = SSH_CHANNEL_OPEN;
1.367 djm 1179: channel_pre_open(ssh, c, readset, writeset);
1.41 markus 1180: } else if (ret == -1) {
1.188 itojun 1181: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1182: debug2("X11 rejected %d i%d/o%d",
1183: c->self, c->istate, c->ostate);
1184: chan_read_failed(ssh, c);
1185: sshbuf_reset(c->input);
1186: chan_ibuf_empty(ssh, c);
1187: sshbuf_reset(c->output);
1188: chan_write_failed(ssh, c);
1.194 markus 1189: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1190: }
1191: }
1.25 markus 1192:
1.302 djm 1193: static void
1.367 djm 1194: channel_pre_mux_client(struct ssh *ssh,
1195: Channel *c, fd_set *readset, fd_set *writeset)
1.302 djm 1196: {
1.304 djm 1197: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1198: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.302 djm 1199: FD_SET(c->rfd, readset);
1200: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1201: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1202: sshbuf_reset(c->input);
1203: chan_ibuf_empty(ssh, c);
1.302 djm 1204: /* Start output drain. XXX just kill chan? */
1.367 djm 1205: chan_rcvd_oclose(ssh, c);
1.302 djm 1206: }
1207: if (c->ostate == CHAN_OUTPUT_OPEN ||
1208: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1209: if (sshbuf_len(c->output) > 0)
1.302 djm 1210: FD_SET(c->wfd, writeset);
1211: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1212: chan_obuf_empty(ssh, c);
1.302 djm 1213: }
1214: }
1215:
1.104 markus 1216: /* try to decode a socks4 header */
1.127 itojun 1217: static int
1.372 markus 1218: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1219: {
1.367 djm 1220: const u_char *p;
1221: char *host;
1.292 djm 1222: u_int len, have, i, found, need;
1.148 deraadt 1223: char username[256];
1.103 markus 1224: struct {
1225: u_int8_t version;
1226: u_int8_t command;
1227: u_int16_t dest_port;
1.104 markus 1228: struct in_addr dest_addr;
1.103 markus 1229: } s4_req, s4_rsp;
1.367 djm 1230: int r;
1.103 markus 1231:
1.104 markus 1232: debug2("channel %d: decode socks4", c->self);
1.109 markus 1233:
1.372 markus 1234: have = sshbuf_len(input);
1.109 markus 1235: len = sizeof(s4_req);
1236: if (have < len)
1237: return 0;
1.372 markus 1238: p = sshbuf_ptr(input);
1.292 djm 1239:
1240: need = 1;
1241: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1242: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1243: debug2("channel %d: socks4a request", c->self);
1244: /* ... and needs an extra string (the hostname) */
1245: need = 2;
1246: }
1247: /* Check for terminating NUL on the string(s) */
1.109 markus 1248: for (found = 0, i = len; i < have; i++) {
1249: if (p[i] == '\0') {
1.292 djm 1250: found++;
1251: if (found == need)
1252: break;
1.109 markus 1253: }
1254: if (i > 1024) {
1255: /* the peer is probably sending garbage */
1256: debug("channel %d: decode socks4: too long",
1257: c->self);
1258: return -1;
1259: }
1260: }
1.292 djm 1261: if (found < need)
1.109 markus 1262: return 0;
1.372 markus 1263: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1264: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1265: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1266: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.367 djm 1267: debug("channels %d: decode socks4: %s", c->self, ssh_err(r));
1268: return -1;
1269: }
1.372 markus 1270: have = sshbuf_len(input);
1271: p = sshbuf_ptr(input);
1.364 djm 1272: if (memchr(p, '\0', have) == NULL) {
1273: error("channel %d: decode socks4: user not nul terminated",
1.331 djm 1274: c->self);
1.364 djm 1275: return -1;
1276: }
1.103 markus 1277: len = strlen(p);
1.106 markus 1278: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1279: len++; /* trailing '\0' */
1.103 markus 1280: strlcpy(username, p, sizeof(username));
1.372 markus 1281: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1282: fatal("%s: channel %d: consume: %s", __func__,
1283: c->self, ssh_err(r));
1284: }
1.321 djm 1285: free(c->path);
1286: c->path = NULL;
1.292 djm 1287: if (need == 1) { /* SOCKS4: one string */
1288: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1289: c->path = xstrdup(host);
1.292 djm 1290: } else { /* SOCKS4A: two strings */
1.372 markus 1291: have = sshbuf_len(input);
1292: p = sshbuf_ptr(input);
1.364 djm 1293: if (memchr(p, '\0', have) == NULL) {
1294: error("channel %d: decode socks4a: host not nul "
1295: "terminated", c->self);
1296: return -1;
1297: }
1.292 djm 1298: len = strlen(p);
1299: debug2("channel %d: decode socks4a: host %s/%d",
1300: c->self, p, len);
1301: len++; /* trailing '\0' */
1.293 djm 1302: if (len > NI_MAXHOST) {
1.292 djm 1303: error("channel %d: hostname \"%.100s\" too long",
1304: c->self, p);
1305: return -1;
1306: }
1.293 djm 1307: c->path = xstrdup(p);
1.372 markus 1308: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1309: fatal("%s: channel %d: consume: %s", __func__,
1310: c->self, ssh_err(r));
1311: }
1.292 djm 1312: }
1.103 markus 1313: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1314:
1.194 markus 1315: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1316: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1317:
1.104 markus 1318: if (s4_req.command != 1) {
1.292 djm 1319: debug("channel %d: cannot handle: %s cn %d",
1320: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1321: return -1;
1.103 markus 1322: }
1.104 markus 1323: s4_rsp.version = 0; /* vn: 0 for reply */
1324: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1325: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1326: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.372 markus 1327: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0) {
1.367 djm 1328: fatal("%s: channel %d: append reply: %s", __func__,
1329: c->self, ssh_err(r));
1330: }
1.104 markus 1331: return 1;
1332: }
1333:
1.193 markus 1334: /* try to decode a socks5 header */
1335: #define SSH_SOCKS5_AUTHDONE 0x1000
1336: #define SSH_SOCKS5_NOAUTH 0x00
1337: #define SSH_SOCKS5_IPV4 0x01
1338: #define SSH_SOCKS5_DOMAIN 0x03
1339: #define SSH_SOCKS5_IPV6 0x04
1340: #define SSH_SOCKS5_CONNECT 0x01
1341: #define SSH_SOCKS5_SUCCESS 0x00
1342:
1343: static int
1.372 markus 1344: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1345: {
1.367 djm 1346: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1347: struct {
1348: u_int8_t version;
1349: u_int8_t command;
1350: u_int8_t reserved;
1351: u_int8_t atyp;
1352: } s5_req, s5_rsp;
1353: u_int16_t dest_port;
1.324 djm 1354: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1355: const u_char *p;
1.252 djm 1356: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1357: int r;
1.193 markus 1358:
1359: debug2("channel %d: decode socks5", c->self);
1.372 markus 1360: p = sshbuf_ptr(input);
1.193 markus 1361: if (p[0] != 0x05)
1362: return -1;
1.372 markus 1363: have = sshbuf_len(input);
1.193 markus 1364: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1365: /* format: ver | nmethods | methods */
1.198 djm 1366: if (have < 2)
1.193 markus 1367: return 0;
1368: nmethods = p[1];
1369: if (have < nmethods + 2)
1370: return 0;
1371: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1372: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1373: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1374: found = 1;
1375: break;
1376: }
1377: }
1378: if (!found) {
1379: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1380: c->self);
1381: return -1;
1382: }
1.372 markus 1383: if ((r = sshbuf_consume(input, nmethods + 2)) != 0) {
1.367 djm 1384: fatal("%s: channel %d: consume: %s", __func__,
1385: c->self, ssh_err(r));
1386: }
1387: /* version, method */
1.372 markus 1388: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1389: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0) {
1.367 djm 1390: fatal("%s: channel %d: append reply: %s", __func__,
1391: c->self, ssh_err(r));
1392: }
1.193 markus 1393: c->flags |= SSH_SOCKS5_AUTHDONE;
1394: debug2("channel %d: socks5 auth done", c->self);
1395: return 0; /* need more */
1396: }
1397: debug2("channel %d: socks5 post auth", c->self);
1398: if (have < sizeof(s5_req)+1)
1399: return 0; /* need more */
1.247 deraadt 1400: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1401: if (s5_req.version != 0x05 ||
1402: s5_req.command != SSH_SOCKS5_CONNECT ||
1403: s5_req.reserved != 0x00) {
1.194 markus 1404: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1405: return -1;
1406: }
1.213 deraadt 1407: switch (s5_req.atyp){
1.193 markus 1408: case SSH_SOCKS5_IPV4:
1409: addrlen = 4;
1410: af = AF_INET;
1411: break;
1412: case SSH_SOCKS5_DOMAIN:
1413: addrlen = p[sizeof(s5_req)];
1414: af = -1;
1415: break;
1416: case SSH_SOCKS5_IPV6:
1417: addrlen = 16;
1418: af = AF_INET6;
1419: break;
1420: default:
1.194 markus 1421: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1422: return -1;
1423: }
1.252 djm 1424: need = sizeof(s5_req) + addrlen + 2;
1425: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1426: need++;
1427: if (have < need)
1.193 markus 1428: return 0;
1.372 markus 1429: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0) {
1.367 djm 1430: fatal("%s: channel %d: consume: %s", __func__,
1431: c->self, ssh_err(r));
1432: }
1433: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1434: /* host string length */
1.372 markus 1435: if ((r = sshbuf_consume(input, 1)) != 0) {
1.367 djm 1436: fatal("%s: channel %d: consume: %s", __func__,
1437: c->self, ssh_err(r));
1438: }
1439: }
1.372 markus 1440: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1441: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.367 djm 1442: debug("channel %d: parse addr/port: %s", c->self, ssh_err(r));
1443: return -1;
1444: }
1.193 markus 1445: dest_addr[addrlen] = '\0';
1.321 djm 1446: free(c->path);
1447: c->path = NULL;
1.293 djm 1448: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1449: if (addrlen >= NI_MAXHOST) {
1.293 djm 1450: error("channel %d: dynamic request: socks5 hostname "
1451: "\"%.100s\" too long", c->self, dest_addr);
1452: return -1;
1453: }
1454: c->path = xstrdup(dest_addr);
1455: } else {
1456: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1457: return -1;
1458: c->path = xstrdup(ntop);
1459: }
1.193 markus 1460: c->host_port = ntohs(dest_port);
1.198 djm 1461:
1.194 markus 1462: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1463: c->self, c->path, c->host_port, s5_req.command);
1464:
1465: s5_rsp.version = 0x05;
1466: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1467: s5_rsp.reserved = 0; /* ignored */
1468: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1469: dest_port = 0; /* ignored */
1470:
1.372 markus 1471: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1472: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1473: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.367 djm 1474: fatal("%s: channel %d: append reply: %s", __func__,
1475: c->self, ssh_err(r));
1.193 markus 1476: return 1;
1.301 dtucker 1477: }
1478:
1479: Channel *
1.367 djm 1480: channel_connect_stdio_fwd(struct ssh *ssh,
1481: const char *host_to_connect, u_short port_to_connect, int in, int out)
1.301 dtucker 1482: {
1483: Channel *c;
1484:
1.367 djm 1485: debug("%s %s:%d", __func__, host_to_connect, port_to_connect);
1.301 dtucker 1486:
1.367 djm 1487: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1488: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1489: 0, "stdio-forward", /*nonblock*/0);
1490:
1491: c->path = xstrdup(host_to_connect);
1492: c->host_port = port_to_connect;
1493: c->listening_port = 0;
1494: c->force_drain = 1;
1495:
1.367 djm 1496: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1497: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1498:
1499: return c;
1.193 markus 1500: }
1501:
1.104 markus 1502: /* dynamic port forwarding */
1.127 itojun 1503: static void
1.367 djm 1504: channel_pre_dynamic(struct ssh *ssh, Channel *c,
1505: fd_set *readset, fd_set *writeset)
1.104 markus 1506: {
1.367 djm 1507: const u_char *p;
1.217 djm 1508: u_int have;
1509: int ret;
1.103 markus 1510:
1.367 djm 1511: have = sshbuf_len(c->input);
1.104 markus 1512: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1513: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1514: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1515: if (have < 3) {
1.104 markus 1516: /* need more */
1517: FD_SET(c->sock, readset);
1518: return;
1519: }
1520: /* try to guess the protocol */
1.367 djm 1521: p = sshbuf_ptr(c->input);
1522: /* XXX sshbuf_peek_u8? */
1.104 markus 1523: switch (p[0]) {
1524: case 0x04:
1.372 markus 1525: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1526: break;
1527: case 0x05:
1.372 markus 1528: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1529: break;
1530: default:
1531: ret = -1;
1532: break;
1533: }
1534: if (ret < 0) {
1.367 djm 1535: chan_mark_dead(ssh, c);
1.104 markus 1536: } else if (ret == 0) {
1537: debug2("channel %d: pre_dynamic: need more", c->self);
1538: /* need more */
1539: FD_SET(c->sock, readset);
1.372 markus 1540: if (sshbuf_len(c->output))
1541: FD_SET(c->sock, writeset);
1.104 markus 1542: } else {
1543: /* switch to the next state */
1544: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1545: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1546: }
1.103 markus 1547: }
1548:
1.372 markus 1549: /* simulate read-error */
1550: static void
1551: rdynamic_close(struct ssh *ssh, Channel *c)
1552: {
1553: c->type = SSH_CHANNEL_OPEN;
1554: chan_read_failed(ssh, c);
1555: sshbuf_reset(c->input);
1556: chan_ibuf_empty(ssh, c);
1557: sshbuf_reset(c->output);
1558: chan_write_failed(ssh, c);
1559: }
1560:
1561: /* reverse dynamic port forwarding */
1562: static void
1563: channel_before_prepare_select_rdynamic(struct ssh *ssh, Channel *c)
1564: {
1565: const u_char *p;
1566: u_int have, len;
1567: int r, ret;
1568:
1569: have = sshbuf_len(c->output);
1570: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1571: /* sshbuf_dump(c->output, stderr); */
1572: /* EOF received */
1573: if (c->flags & CHAN_EOF_RCVD) {
1574: if ((r = sshbuf_consume(c->output, have)) != 0) {
1575: fatal("%s: channel %d: consume: %s",
1576: __func__, c->self, ssh_err(r));
1577: }
1578: rdynamic_close(ssh, c);
1579: return;
1580: }
1581: /* check if the fixed size part of the packet is in buffer. */
1582: if (have < 3)
1583: return;
1584: /* try to guess the protocol */
1585: p = sshbuf_ptr(c->output);
1586: switch (p[0]) {
1587: case 0x04:
1588: /* switch input/output for reverse forwarding */
1589: ret = channel_decode_socks4(c, c->output, c->input);
1590: break;
1591: case 0x05:
1592: ret = channel_decode_socks5(c, c->output, c->input);
1593: break;
1594: default:
1595: ret = -1;
1596: break;
1597: }
1598: if (ret < 0) {
1599: rdynamic_close(ssh, c);
1600: } else if (ret == 0) {
1601: debug2("channel %d: pre_rdynamic: need more", c->self);
1602: /* send socks request to peer */
1603: len = sshbuf_len(c->input);
1604: if (len > 0 && len < c->remote_window) {
1605: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1606: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1607: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1608: (r = sshpkt_send(ssh)) != 0) {
1609: fatal("%s: channel %i: rdynamic: %s", __func__,
1610: c->self, ssh_err(r));
1611: }
1612: if ((r = sshbuf_consume(c->input, len)) != 0) {
1613: fatal("%s: channel %d: consume: %s",
1614: __func__, c->self, ssh_err(r));
1615: }
1616: c->remote_window -= len;
1617: }
1618: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1619: /* the connect failed */
1620: rdynamic_close(ssh, c);
1621: }
1622: }
1623:
1.41 markus 1624: /* This is our fake X11 server socket. */
1.127 itojun 1625: static void
1.367 djm 1626: channel_post_x11_listener(struct ssh *ssh, Channel *c,
1627: fd_set *readset, fd_set *writeset)
1.41 markus 1628: {
1.113 markus 1629: Channel *nc;
1.285 djm 1630: struct sockaddr_storage addr;
1.367 djm 1631: int r, newsock, oerrno, remote_port;
1.41 markus 1632: socklen_t addrlen;
1.85 markus 1633: char buf[16384], *remote_ipaddr;
1.25 markus 1634:
1.367 djm 1635: if (!FD_ISSET(c->sock, readset))
1636: return;
1637:
1638: debug("X11 connection requested.");
1639: addrlen = sizeof(addr);
1640: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1641: if (c->single_connection) {
1642: oerrno = errno;
1643: debug2("single_connection: closing X11 listener.");
1644: channel_close_fd(ssh, &c->sock);
1645: chan_mark_dead(ssh, c);
1646: errno = oerrno;
1647: }
1648: if (newsock < 0) {
1649: if (errno != EINTR && errno != EWOULDBLOCK &&
1650: errno != ECONNABORTED)
1651: error("accept: %.100s", strerror(errno));
1652: if (errno == EMFILE || errno == ENFILE)
1653: c->notbefore = monotime() + 1;
1654: return;
1655: }
1656: set_nodelay(newsock);
1657: remote_ipaddr = get_peer_ipaddr(newsock);
1658: remote_port = get_peer_port(newsock);
1659: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1660: remote_ipaddr, remote_port);
1661:
1662: nc = channel_new(ssh, "accepted x11 socket",
1663: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1664: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1665: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1666: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1667: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.367 djm 1668: fatal("%s: channel %i: reply %s", __func__,
1669: c->self, ssh_err(r));
1.41 markus 1670: }
1.367 djm 1671: if ((r = sshpkt_send(ssh)) != 0)
1672: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1673: free(remote_ipaddr);
1.41 markus 1674: }
1.25 markus 1675:
1.127 itojun 1676: static void
1.367 djm 1677: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1678: {
1.328 djm 1679: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1680: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1681: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1682: int remote_port = get_peer_port(c->sock);
1.367 djm 1683: int r;
1.303 djm 1684:
1685: if (remote_port == -1) {
1686: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1687: free(remote_ipaddr);
1.303 djm 1688: remote_ipaddr = xstrdup("127.0.0.1");
1689: remote_port = 65535;
1690: }
1.103 markus 1691:
1.367 djm 1692: free(c->remote_name);
1693: xasprintf(&c->remote_name,
1.103 markus 1694: "%s: listening port %d for %.100s port %d, "
1.328 djm 1695: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1696: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1697: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1698:
1.367 djm 1699: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1700: if (strcmp(rtype, "direct-tcpip") == 0) {
1701: /* target host, port */
1.367 djm 1702: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1703: (r = sshpkt_put_u32(ssh, c->host_port)) != 0) {
1704: fatal("%s: channel %i: reply %s", __func__,
1705: c->self, ssh_err(r));
1706: }
1.358 djm 1707: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1708: /* target path */
1.367 djm 1709: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1710: fatal("%s: channel %i: reply %s", __func__,
1711: c->self, ssh_err(r));
1712: }
1.358 djm 1713: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1714: /* listen path */
1.367 djm 1715: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1716: fatal("%s: channel %i: reply %s", __func__,
1717: c->self, ssh_err(r));
1718: }
1.103 markus 1719: } else {
1.358 djm 1720: /* listen address, port */
1.367 djm 1721: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1722: (r = sshpkt_put_u32(ssh, local_port)) != 0) {
1723: fatal("%s: channel %i: reply %s", __func__,
1724: c->self, ssh_err(r));
1725: }
1.358 djm 1726: }
1727: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1728: /* reserved for future owner/mode info */
1.367 djm 1729: if ((r = sshpkt_put_cstring(ssh, "")) != 0) {
1730: fatal("%s: channel %i: reply %s", __func__,
1731: c->self, ssh_err(r));
1732: }
1.358 djm 1733: } else {
1734: /* originator host and port */
1.367 djm 1735: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1736: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0) {
1737: fatal("%s: channel %i: reply %s", __func__,
1738: c->self, ssh_err(r));
1739: }
1.103 markus 1740: }
1.367 djm 1741: if ((r = sshpkt_send(ssh)) != 0)
1742: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1.321 djm 1743: free(remote_ipaddr);
1.328 djm 1744: free(local_ipaddr);
1.103 markus 1745: }
1746:
1.347 djm 1747: void
1.367 djm 1748: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1749: {
1.367 djm 1750: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1751: }
1752:
1.41 markus 1753: /*
1754: * This socket is listening for connections to a forwarded TCP/IP port.
1755: */
1.127 itojun 1756: static void
1.367 djm 1757: channel_post_port_listener(struct ssh *ssh, Channel *c,
1758: fd_set *readset, fd_set *writeset)
1.41 markus 1759: {
1.103 markus 1760: Channel *nc;
1.285 djm 1761: struct sockaddr_storage addr;
1.113 markus 1762: int newsock, nextstate;
1.41 markus 1763: socklen_t addrlen;
1.103 markus 1764: char *rtype;
1.73 markus 1765:
1.367 djm 1766: if (!FD_ISSET(c->sock, readset))
1767: return;
1768:
1769: debug("Connection to port %d forwarding to %.100s port %d requested.",
1770: c->listening_port, c->path, c->host_port);
1.103 markus 1771:
1.367 djm 1772: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1773: nextstate = SSH_CHANNEL_OPENING;
1774: rtype = "forwarded-tcpip";
1775: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1776: nextstate = SSH_CHANNEL_OPENING;
1777: rtype = "forwarded-streamlocal@openssh.com";
1778: } else if (c->host_port == PORT_STREAMLOCAL) {
1779: nextstate = SSH_CHANNEL_OPENING;
1780: rtype = "direct-streamlocal@openssh.com";
1781: } else if (c->host_port == 0) {
1782: nextstate = SSH_CHANNEL_DYNAMIC;
1783: rtype = "dynamic-tcpip";
1784: } else {
1785: nextstate = SSH_CHANNEL_OPENING;
1786: rtype = "direct-tcpip";
1787: }
1.103 markus 1788:
1.367 djm 1789: addrlen = sizeof(addr);
1790: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1791: if (newsock < 0) {
1792: if (errno != EINTR && errno != EWOULDBLOCK &&
1793: errno != ECONNABORTED)
1794: error("accept: %.100s", strerror(errno));
1795: if (errno == EMFILE || errno == ENFILE)
1796: c->notbefore = monotime() + 1;
1797: return;
1.41 markus 1798: }
1.367 djm 1799: if (c->host_port != PORT_STREAMLOCAL)
1800: set_nodelay(newsock);
1801: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1802: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1803: nc->listening_port = c->listening_port;
1804: nc->host_port = c->host_port;
1805: if (c->path != NULL)
1806: nc->path = xstrdup(c->path);
1807:
1808: if (nextstate != SSH_CHANNEL_DYNAMIC)
1809: port_open_helper(ssh, nc, rtype);
1.41 markus 1810: }
1.25 markus 1811:
1.41 markus 1812: /*
1813: * This is the authentication agent socket listening for connections from
1814: * clients.
1815: */
1.127 itojun 1816: static void
1.367 djm 1817: channel_post_auth_listener(struct ssh *ssh, Channel *c,
1818: fd_set *readset, fd_set *writeset)
1.41 markus 1819: {
1.113 markus 1820: Channel *nc;
1.367 djm 1821: int r, newsock;
1.285 djm 1822: struct sockaddr_storage addr;
1.41 markus 1823: socklen_t addrlen;
1.25 markus 1824:
1.367 djm 1825: if (!FD_ISSET(c->sock, readset))
1826: return;
1827:
1828: addrlen = sizeof(addr);
1829: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1830: if (newsock < 0) {
1831: error("accept from auth socket: %.100s", strerror(errno));
1832: if (errno == EMFILE || errno == ENFILE)
1833: c->notbefore = monotime() + 1;
1834: return;
1.41 markus 1835: }
1.367 djm 1836: nc = channel_new(ssh, "accepted auth socket",
1837: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1838: c->local_window_max, c->local_maxpacket,
1839: 0, "accepted auth socket", 1);
1840: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1841: if ((r = sshpkt_send(ssh)) != 0)
1842: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.41 markus 1843: }
1.25 markus 1844:
1.127 itojun 1845: static void
1.367 djm 1846: channel_post_connecting(struct ssh *ssh, Channel *c,
1847: fd_set *readset, fd_set *writeset)
1.75 markus 1848: {
1.372 markus 1849: int err = 0, sock, isopen, r;
1.129 stevesk 1850: socklen_t sz = sizeof(err);
1.114 markus 1851:
1.367 djm 1852: if (!FD_ISSET(c->sock, writeset))
1853: return;
1.368 djm 1854: if (!c->have_remote_id)
1855: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.372 markus 1856: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1857: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.367 djm 1858: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1859: err = errno;
1860: error("getsockopt SO_ERROR failed");
1861: }
1862: if (err == 0) {
1863: debug("channel %d: connected to %s port %d",
1864: c->self, c->connect_ctx.host, c->connect_ctx.port);
1865: channel_connect_ctx_free(&c->connect_ctx);
1866: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1867: if (isopen) {
1868: /* no message necessary */
1869: } else {
1870: if ((r = sshpkt_start(ssh,
1871: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1872: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1873: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1874: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1875: (r = sshpkt_put_u32(ssh, c->local_maxpacket))
1876: != 0)
1877: fatal("%s: channel %i: confirm: %s", __func__,
1878: c->self, ssh_err(r));
1879: if ((r = sshpkt_send(ssh)) != 0)
1880: fatal("%s: channel %i: %s", __func__, c->self,
1881: ssh_err(r));
1.367 djm 1882: }
1883: } else {
1884: debug("channel %d: connection failed: %s",
1885: c->self, strerror(err));
1886: /* Try next address, if any */
1887: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1888: close(c->sock);
1889: c->sock = c->rfd = c->wfd = sock;
1890: channel_find_maxfd(ssh->chanctxt);
1891: return;
1892: }
1893: /* Exhausted all addresses */
1894: error("connect_to %.100s port %d: failed.",
1895: c->connect_ctx.host, c->connect_ctx.port);
1896: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1897: if (isopen) {
1898: rdynamic_close(ssh, c);
1899: } else {
1900: if ((r = sshpkt_start(ssh,
1901: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1902: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 1903: (r = sshpkt_put_u32(ssh,
1904: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
1905: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1906: (r = sshpkt_put_cstring(ssh, "")) != 0) {
1.372 markus 1907: fatal("%s: channel %i: failure: %s", __func__,
1908: c->self, ssh_err(r));
1.378 djm 1909: }
1.372 markus 1910: if ((r = sshpkt_send(ssh)) != 0)
1911: fatal("%s: channel %i: %s", __func__, c->self,
1912: ssh_err(r));
1913: chan_mark_dead(ssh, c);
1.75 markus 1914: }
1915: }
1916: }
1917:
1.127 itojun 1918: static int
1.367 djm 1919: channel_handle_rfd(struct ssh *ssh, Channel *c,
1920: fd_set *readset, fd_set *writeset)
1.41 markus 1921: {
1.214 markus 1922: char buf[CHAN_RBUF];
1.367 djm 1923: ssize_t len;
1924: int r;
1.25 markus 1925:
1.367 djm 1926: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
1927: return 1;
1928:
1929: len = read(c->rfd, buf, sizeof(buf));
1930: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1931: return 1;
1932: if (len <= 0) {
1933: debug2("channel %d: read<=0 rfd %d len %zd",
1934: c->self, c->rfd, len);
1935: if (c->type != SSH_CHANNEL_OPEN) {
1936: debug2("channel %d: not open", c->self);
1937: chan_mark_dead(ssh, c);
1.41 markus 1938: return -1;
1.65 markus 1939: } else {
1.367 djm 1940: chan_read_failed(ssh, c);
1.65 markus 1941: }
1.367 djm 1942: return -1;
1943: }
1944: if (c->input_filter != NULL) {
1945: if (c->input_filter(ssh, c, buf, len) == -1) {
1946: debug2("channel %d: filter stops", c->self);
1947: chan_read_failed(ssh, c);
1948: }
1949: } else if (c->datagram) {
1950: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1951: fatal("%s: channel %d: put datagram: %s", __func__,
1952: c->self, ssh_err(r));
1953: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
1954: fatal("%s: channel %d: put data: %s", __func__,
1955: c->self, ssh_err(r));
1.41 markus 1956: }
1957: return 1;
1958: }
1.241 deraadt 1959:
1.127 itojun 1960: static int
1.367 djm 1961: channel_handle_wfd(struct ssh *ssh, Channel *c,
1962: fd_set *readset, fd_set *writeset)
1.41 markus 1963: {
1.95 markus 1964: struct termios tio;
1.367 djm 1965: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1966: size_t dlen, olen = 0;
1967: int r, len;
1968:
1969: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
1970: sshbuf_len(c->output) == 0)
1971: return 1;
1.25 markus 1972:
1.41 markus 1973: /* Send buffered output data to the socket. */
1.367 djm 1974: olen = sshbuf_len(c->output);
1975: if (c->output_filter != NULL) {
1976: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1977: debug2("channel %d: filter stops", c->self);
1978: if (c->type != SSH_CHANNEL_OPEN)
1979: chan_mark_dead(ssh, c);
1980: else
1981: chan_write_failed(ssh, c);
1982: return -1;
1.231 reyk 1983: }
1.367 djm 1984: } else if (c->datagram) {
1985: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1986: fatal("%s: channel %d: get datagram: %s", __func__,
1987: c->self, ssh_err(r));
1.369 djm 1988: buf = data;
1.367 djm 1989: } else {
1990: buf = data = sshbuf_mutable_ptr(c->output);
1991: dlen = sshbuf_len(c->output);
1992: }
1.231 reyk 1993:
1.367 djm 1994: if (c->datagram) {
1995: /* ignore truncated writes, datagrams might get lost */
1.374 djm 1996: len = write(c->wfd, buf, dlen);
1.367 djm 1997: free(data);
1.53 markus 1998: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1999: return 1;
1.367 djm 2000: if (len <= 0)
2001: goto write_fail;
2002: goto out;
2003: }
2004:
2005: len = write(c->wfd, buf, dlen);
2006: if (len < 0 && (errno == EINTR || errno == EAGAIN))
2007: return 1;
2008: if (len <= 0) {
2009: write_fail:
2010: if (c->type != SSH_CHANNEL_OPEN) {
2011: debug2("channel %d: not open", c->self);
2012: chan_mark_dead(ssh, c);
1.41 markus 2013: return -1;
1.367 djm 2014: } else {
2015: chan_write_failed(ssh, c);
1.91 markus 2016: }
1.367 djm 2017: return -1;
2018: }
2019: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2020: if (tcgetattr(c->wfd, &tio) == 0 &&
2021: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2022: /*
2023: * Simulate echo to reduce the impact of
2024: * traffic analysis. We need to match the
2025: * size of a SSH2_MSG_CHANNEL_DATA message
2026: * (4 byte channel id + buf)
2027: */
2028: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2029: (r = sshpkt_send(ssh)) != 0)
2030: fatal("%s: channel %d: ignore: %s",
2031: __func__, c->self, ssh_err(r));
1.25 markus 2032: }
1.367 djm 2033: }
2034: if ((r = sshbuf_consume(c->output, len)) != 0) {
2035: fatal("%s: channel %d: consume: %s",
2036: __func__, c->self, ssh_err(r));
1.44 markus 2037: }
1.309 djm 2038: out:
1.367 djm 2039: c->local_consumed += olen - sshbuf_len(c->output);
2040:
2041: return 1;
2042: }
2043:
2044: static int
2045: channel_handle_efd_write(struct ssh *ssh, Channel *c,
2046: fd_set *readset, fd_set *writeset)
2047: {
2048: int r;
2049: ssize_t len;
2050:
2051: if (!FD_ISSET(c->efd, writeset) || sshbuf_len(c->extended) == 0)
2052: return 1;
2053:
2054: len = write(c->efd, sshbuf_ptr(c->extended),
2055: sshbuf_len(c->extended));
2056: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
2057: if (len < 0 && (errno == EINTR || errno == EAGAIN))
2058: return 1;
2059: if (len <= 0) {
2060: debug2("channel %d: closing write-efd %d", c->self, c->efd);
2061: channel_close_fd(ssh, &c->efd);
2062: } else {
2063: if ((r = sshbuf_consume(c->extended, len)) != 0) {
2064: fatal("%s: channel %d: consume: %s",
2065: __func__, c->self, ssh_err(r));
2066: }
2067: c->local_consumed += len;
2068: }
1.44 markus 2069: return 1;
2070: }
1.241 deraadt 2071:
1.127 itojun 2072: static int
1.367 djm 2073: channel_handle_efd_read(struct ssh *ssh, Channel *c,
2074: fd_set *readset, fd_set *writeset)
1.44 markus 2075: {
1.214 markus 2076: char buf[CHAN_RBUF];
1.367 djm 2077: int r;
2078: ssize_t len;
2079:
2080: if (!FD_ISSET(c->efd, readset))
2081: return 1;
1.44 markus 2082:
1.367 djm 2083: len = read(c->efd, buf, sizeof(buf));
2084: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
2085: if (len < 0 && (errno == EINTR || errno == EAGAIN))
2086: return 1;
2087: if (len <= 0) {
2088: debug2("channel %d: closing read-efd %d",
2089: c->self, c->efd);
2090: channel_close_fd(ssh, &c->efd);
2091: } else {
2092: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
2093: debug3("channel %d: discard efd",
2094: c->self);
2095: } else if ((r = sshbuf_put(c->extended, buf, len)) != 0) {
2096: fatal("%s: channel %d: append: %s",
2097: __func__, c->self, ssh_err(r));
1.44 markus 2098: }
2099: }
2100: return 1;
2101: }
1.241 deraadt 2102:
1.127 itojun 2103: static int
1.367 djm 2104: channel_handle_efd(struct ssh *ssh, Channel *c,
2105: fd_set *readset, fd_set *writeset)
1.44 markus 2106: {
1.367 djm 2107: if (c->efd == -1)
2108: return 1;
2109:
2110: /** XXX handle drain efd, too */
2111:
2112: if (c->extended_usage == CHAN_EXTENDED_WRITE)
2113: return channel_handle_efd_write(ssh, c, readset, writeset);
2114: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2115: c->extended_usage == CHAN_EXTENDED_IGNORE)
2116: return channel_handle_efd_read(ssh, c, readset, writeset);
2117:
2118: return 1;
2119: }
2120:
2121: static int
2122: channel_check_window(struct ssh *ssh, Channel *c)
2123: {
2124: int r;
2125:
1.104 markus 2126: if (c->type == SSH_CHANNEL_OPEN &&
2127: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2128: ((c->local_window_max - c->local_window >
1.269 markus 2129: c->local_maxpacket*3) ||
2130: c->local_window < c->local_window_max/2) &&
1.44 markus 2131: c->local_consumed > 0) {
1.368 djm 2132: if (!c->have_remote_id)
2133: fatal(":%s: channel %d: no remote id",
2134: __func__, c->self);
1.367 djm 2135: if ((r = sshpkt_start(ssh,
2136: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2137: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2138: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2139: (r = sshpkt_send(ssh)) != 0) {
2140: fatal("%s: channel %i: %s", __func__,
2141: c->self, ssh_err(r));
2142: }
1.70 markus 2143: debug2("channel %d: window %d sent adjust %d",
1.44 markus 2144: c->self, c->local_window,
2145: c->local_consumed);
2146: c->local_window += c->local_consumed;
2147: c->local_consumed = 0;
1.1 deraadt 2148: }
1.41 markus 2149: return 1;
1.1 deraadt 2150: }
2151:
1.127 itojun 2152: static void
1.367 djm 2153: channel_post_open(struct ssh *ssh, Channel *c,
2154: fd_set *readset, fd_set *writeset)
1.41 markus 2155: {
1.367 djm 2156: channel_handle_rfd(ssh, c, readset, writeset);
2157: channel_handle_wfd(ssh, c, readset, writeset);
2158: channel_handle_efd(ssh, c, readset, writeset);
2159: channel_check_window(ssh, c);
1.44 markus 2160: }
2161:
1.302 djm 2162: static u_int
1.367 djm 2163: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2164: {
2165: char buf[CHAN_RBUF];
1.367 djm 2166: ssize_t len;
1.302 djm 2167: u_int rlen;
1.367 djm 2168: int r;
1.302 djm 2169:
1.367 djm 2170: if (sshbuf_len(c->input) < need) {
2171: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2172: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.349 naddy 2173: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2174: return sshbuf_len(c->input);
1.302 djm 2175: if (len <= 0) {
1.367 djm 2176: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2177: c->self, c->rfd, len);
1.367 djm 2178: chan_read_failed(ssh, c);
1.349 naddy 2179: return 0;
1.367 djm 2180: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
2181: fatal("%s: channel %d: append: %s",
2182: __func__, c->self, ssh_err(r));
2183: }
1.302 djm 2184: }
1.367 djm 2185: return sshbuf_len(c->input);
1.302 djm 2186: }
2187:
2188: static void
1.367 djm 2189: channel_post_mux_client_read(struct ssh *ssh, Channel *c,
2190: fd_set *readset, fd_set *writeset)
1.302 djm 2191: {
2192: u_int need;
2193:
1.367 djm 2194: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
2195: return;
2196: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2197: return;
2198: if (c->mux_pause)
2199: return;
2200:
2201: /*
2202: * Don't not read past the precise end of packets to
2203: * avoid disrupting fd passing.
2204: */
2205: if (read_mux(ssh, c, 4) < 4) /* read header */
2206: return;
2207: /* XXX sshbuf_peek_u32 */
2208: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2209: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2210: if (need > CHANNEL_MUX_MAX_PACKET) {
2211: debug2("channel %d: packet too big %u > %u",
2212: c->self, CHANNEL_MUX_MAX_PACKET, need);
2213: chan_rcvd_oclose(ssh, c);
2214: return;
2215: }
2216: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2217: return;
2218: if (c->mux_rcb(ssh, c) != 0) {
2219: debug("channel %d: mux_rcb failed", c->self);
2220: chan_mark_dead(ssh, c);
2221: return;
1.302 djm 2222: }
1.367 djm 2223: }
2224:
2225: static void
2226: channel_post_mux_client_write(struct ssh *ssh, Channel *c,
2227: fd_set *readset, fd_set *writeset)
2228: {
2229: ssize_t len;
2230: int r;
1.302 djm 2231:
1.367 djm 2232: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
2233: sshbuf_len(c->output) == 0)
2234: return;
2235:
2236: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
2237: if (len < 0 && (errno == EINTR || errno == EAGAIN))
2238: return;
2239: if (len <= 0) {
2240: chan_mark_dead(ssh, c);
2241: return;
1.302 djm 2242: }
1.367 djm 2243: if ((r = sshbuf_consume(c->output, len)) != 0)
2244: fatal("%s: channel %d: consume: %s", __func__,
2245: c->self, ssh_err(r));
2246: }
2247:
2248: static void
2249: channel_post_mux_client(struct ssh *ssh, Channel *c,
2250: fd_set *readset, fd_set *writeset)
2251: {
2252: channel_post_mux_client_read(ssh, c, readset, writeset);
2253: channel_post_mux_client_write(ssh, c, readset, writeset);
1.302 djm 2254: }
2255:
2256: static void
1.367 djm 2257: channel_post_mux_listener(struct ssh *ssh, Channel *c,
2258: fd_set *readset, fd_set *writeset)
1.302 djm 2259: {
2260: Channel *nc;
2261: struct sockaddr_storage addr;
2262: socklen_t addrlen;
2263: int newsock;
2264: uid_t euid;
2265: gid_t egid;
2266:
2267: if (!FD_ISSET(c->sock, readset))
2268: return;
2269:
2270: debug("multiplexing control connection");
2271:
2272: /*
2273: * Accept connection on control socket
2274: */
2275: memset(&addr, 0, sizeof(addr));
2276: addrlen = sizeof(addr);
2277: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2278: &addrlen)) == -1) {
2279: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 2280: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2281: c->notbefore = monotime() + 1;
1.302 djm 2282: return;
2283: }
2284:
2285: if (getpeereid(newsock, &euid, &egid) < 0) {
2286: error("%s getpeereid failed: %s", __func__,
2287: strerror(errno));
2288: close(newsock);
2289: return;
2290: }
2291: if ((euid != 0) && (getuid() != euid)) {
2292: error("multiplex uid mismatch: peer euid %u != uid %u",
2293: (u_int)euid, (u_int)getuid());
2294: close(newsock);
2295: return;
2296: }
1.367 djm 2297: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2298: newsock, newsock, -1, c->local_window_max,
2299: c->local_maxpacket, 0, "mux-control", 1);
2300: nc->mux_rcb = c->mux_rcb;
1.367 djm 2301: debug3("%s: new mux channel %d fd %d", __func__, nc->self, nc->sock);
1.302 djm 2302: /* establish state */
1.367 djm 2303: nc->mux_rcb(ssh, nc);
1.302 djm 2304: /* mux state transitions must not elicit protocol messages */
2305: nc->flags |= CHAN_LOCAL;
2306: }
2307:
1.127 itojun 2308: static void
1.367 djm 2309: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2310: {
1.367 djm 2311: chan_fn **pre, **post;
2312:
2313: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
2314: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
2315: fatal("%s: allocation failed", __func__);
2316:
2317: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2318: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2319: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2320: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2321: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2322: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2323: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2324: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2325: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2326: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2327: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2328: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2329: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2330:
2331: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2332: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2333: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2334: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2335: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2336: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2337: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2338: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2339: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2340: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2341: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2342: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2343:
1.367 djm 2344: sc->channel_pre = pre;
2345: sc->channel_post = post;
1.44 markus 2346: }
2347:
1.140 markus 2348: /* gc dead channels */
2349: static void
1.367 djm 2350: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2351: {
2352: if (c == NULL)
2353: return;
2354: if (c->detach_user != NULL) {
1.367 djm 2355: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2356: return;
1.385 djm 2357:
1.194 markus 2358: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2359: c->detach_user(ssh, c->self, NULL);
1.140 markus 2360: /* if we still have a callback */
2361: if (c->detach_user != NULL)
2362: return;
1.194 markus 2363: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2364: }
1.367 djm 2365: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2366: return;
1.194 markus 2367: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2368: channel_free(ssh, c);
1.140 markus 2369: }
2370:
1.367 djm 2371: enum channel_table { CHAN_PRE, CHAN_POST };
2372:
1.127 itojun 2373: static void
1.367 djm 2374: channel_handler(struct ssh *ssh, int table,
1.366 djm 2375: fd_set *readset, fd_set *writeset, time_t *unpause_secs)
1.41 markus 2376: {
1.367 djm 2377: struct ssh_channels *sc = ssh->chanctxt;
2378: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2379: u_int i, oalloc;
1.41 markus 2380: Channel *c;
1.317 djm 2381: time_t now;
1.25 markus 2382:
1.322 dtucker 2383: now = monotime();
1.317 djm 2384: if (unpause_secs != NULL)
2385: *unpause_secs = 0;
1.367 djm 2386: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2387: c = sc->channels[i];
1.113 markus 2388: if (c == NULL)
1.41 markus 2389: continue;
1.299 markus 2390: if (c->delayed) {
1.367 djm 2391: if (table == CHAN_PRE)
1.299 markus 2392: c->delayed = 0;
2393: else
2394: continue;
2395: }
1.317 djm 2396: if (ftab[c->type] != NULL) {
2397: /*
2398: * Run handlers that are not paused.
2399: */
2400: if (c->notbefore <= now)
1.367 djm 2401: (*ftab[c->type])(ssh, c, readset, writeset);
1.317 djm 2402: else if (unpause_secs != NULL) {
2403: /*
2404: * Collect the time that the earliest
2405: * channel comes off pause.
2406: */
2407: debug3("%s: chan %d: skip for %d more seconds",
2408: __func__, c->self,
2409: (int)(c->notbefore - now));
2410: if (*unpause_secs == 0 ||
2411: (c->notbefore - now) < *unpause_secs)
2412: *unpause_secs = c->notbefore - now;
2413: }
2414: }
1.367 djm 2415: channel_garbage_collect(ssh, c);
1.1 deraadt 2416: }
1.317 djm 2417: if (unpause_secs != NULL && *unpause_secs != 0)
2418: debug3("%s: first channel unpauses in %d seconds",
2419: __func__, (int)*unpause_secs);
1.1 deraadt 2420: }
2421:
1.121 markus 2422: /*
1.372 markus 2423: * Create sockets before allocating the select bitmasks.
2424: * This is necessary for things that need to happen after reading
2425: * the network-input but before channel_prepare_select().
2426: */
2427: static void
2428: channel_before_prepare_select(struct ssh *ssh)
2429: {
2430: struct ssh_channels *sc = ssh->chanctxt;
2431: Channel *c;
2432: u_int i, oalloc;
2433:
2434: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2435: c = sc->channels[i];
2436: if (c == NULL)
2437: continue;
2438: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
2439: channel_before_prepare_select_rdynamic(ssh, c);
2440: }
2441: }
2442:
2443: /*
1.121 markus 2444: * Allocate/update select bitmasks and add any bits relevant to channels in
2445: * select bitmasks.
2446: */
1.49 markus 2447: void
1.366 djm 2448: channel_prepare_select(struct ssh *ssh, fd_set **readsetp, fd_set **writesetp,
2449: int *maxfdp, u_int *nallocp, time_t *minwait_secs)
1.41 markus 2450: {
1.243 djm 2451: u_int n, sz, nfdset;
1.84 markus 2452:
1.372 markus 2453: channel_before_prepare_select(ssh); /* might update channel_max_fd */
2454:
1.367 djm 2455: n = MAXIMUM(*maxfdp, ssh->chanctxt->channel_max_fd);
1.84 markus 2456:
1.243 djm 2457: nfdset = howmany(n+1, NFDBITS);
2458: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2459: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2460: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2461: sz = nfdset * sizeof(fd_mask);
2462:
1.132 markus 2463: /* perhaps check sz < nalloc/2 and shrink? */
2464: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2465: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2466: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2467: *nallocp = sz;
1.84 markus 2468: }
1.132 markus 2469: *maxfdp = n;
1.84 markus 2470: memset(*readsetp, 0, sz);
2471: memset(*writesetp, 0, sz);
2472:
1.366 djm 2473: if (!ssh_packet_is_rekeying(ssh))
1.367 djm 2474: channel_handler(ssh, CHAN_PRE, *readsetp, *writesetp,
1.317 djm 2475: minwait_secs);
1.41 markus 2476: }
2477:
1.121 markus 2478: /*
2479: * After select, perform any appropriate operations for channels which have
2480: * events pending.
2481: */
1.49 markus 2482: void
1.366 djm 2483: channel_after_select(struct ssh *ssh, fd_set *readset, fd_set *writeset)
1.41 markus 2484: {
1.367 djm 2485: channel_handler(ssh, CHAN_POST, readset, writeset, NULL);
2486: }
2487:
2488: /*
2489: * Enqueue data for channels with open or draining c->input.
2490: */
2491: static void
2492: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2493: {
1.373 djm 2494: size_t len, plen;
2495: const u_char *pkt;
1.367 djm 2496: int r;
2497:
2498: if ((len = sshbuf_len(c->input)) == 0) {
2499: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2500: /*
2501: * input-buffer is empty and read-socket shutdown:
2502: * tell peer, that we will not send more data:
2503: * send IEOF.
2504: * hack for extended data: delay EOF if EFD still
2505: * in use.
2506: */
2507: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2508: debug2("channel %d: "
2509: "ibuf_empty delayed efd %d/(%zu)",
2510: c->self, c->efd, sshbuf_len(c->extended));
2511: else
2512: chan_ibuf_empty(ssh, c);
2513: }
2514: return;
2515: }
2516:
1.368 djm 2517: if (!c->have_remote_id)
2518: fatal(":%s: channel %d: no remote id", __func__, c->self);
2519:
1.367 djm 2520: if (c->datagram) {
2521: /* Check datagram will fit; drop if not */
1.373 djm 2522: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
2523: fatal("%s: channel %d: get datagram: %s", __func__,
1.367 djm 2524: c->self, ssh_err(r));
2525: /*
2526: * XXX this does tail-drop on the datagram queue which is
2527: * usually suboptimal compared to head-drop. Better to have
2528: * backpressure at read time? (i.e. read + discard)
2529: */
1.373 djm 2530: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2531: debug("channel %d: datagram too big", c->self);
2532: return;
2533: }
2534: /* Enqueue it */
2535: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2536: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2537: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.367 djm 2538: (r = sshpkt_send(ssh)) != 0) {
2539: fatal("%s: channel %i: datagram: %s", __func__,
2540: c->self, ssh_err(r));
2541: }
1.373 djm 2542: c->remote_window -= plen;
1.367 djm 2543: return;
2544: }
2545:
2546: /* Enqueue packet for buffered data. */
2547: if (len > c->remote_window)
2548: len = c->remote_window;
2549: if (len > c->remote_maxpacket)
2550: len = c->remote_maxpacket;
2551: if (len == 0)
2552: return;
2553: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2554: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2555: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
2556: (r = sshpkt_send(ssh)) != 0) {
2557: fatal("%s: channel %i: data: %s", __func__,
2558: c->self, ssh_err(r));
2559: }
2560: if ((r = sshbuf_consume(c->input, len)) != 0)
2561: fatal("%s: channel %i: consume: %s", __func__,
2562: c->self, ssh_err(r));
2563: c->remote_window -= len;
1.41 markus 2564: }
2565:
1.367 djm 2566: /*
2567: * Enqueue data for channels with open c->extended in read mode.
2568: */
2569: static void
2570: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2571: {
2572: size_t len;
2573: int r;
2574:
2575: if ((len = sshbuf_len(c->extended)) == 0)
2576: return;
2577:
2578: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2579: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2580: if (len > c->remote_window)
2581: len = c->remote_window;
2582: if (len > c->remote_maxpacket)
2583: len = c->remote_maxpacket;
2584: if (len == 0)
2585: return;
1.368 djm 2586: if (!c->have_remote_id)
2587: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.367 djm 2588: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2589: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2590: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2591: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
2592: (r = sshpkt_send(ssh)) != 0) {
2593: fatal("%s: channel %i: data: %s", __func__,
2594: c->self, ssh_err(r));
2595: }
2596: if ((r = sshbuf_consume(c->extended, len)) != 0)
2597: fatal("%s: channel %i: consume: %s", __func__,
2598: c->self, ssh_err(r));
2599: c->remote_window -= len;
2600: debug2("channel %d: sent ext data %zu", c->self, len);
2601: }
1.121 markus 2602:
1.84 markus 2603: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2604: void
1.367 djm 2605: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2606: {
1.367 djm 2607: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2608: Channel *c;
1.367 djm 2609: u_int i;
1.1 deraadt 2610:
1.367 djm 2611: for (i = 0; i < sc->channels_alloc; i++) {
2612: c = sc->channels[i];
1.113 markus 2613: if (c == NULL)
2614: continue;
1.37 markus 2615:
1.121 markus 2616: /*
2617: * We are only interested in channels that can have buffered
2618: * incoming data.
2619: */
1.358 djm 2620: if (c->type != SSH_CHANNEL_OPEN)
2621: continue;
2622: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2623: /* XXX is this true? */
1.367 djm 2624: debug3("channel %d: will not send data after close",
2625: c->self);
1.44 markus 2626: continue;
2627: }
1.25 markus 2628:
2629: /* Get the amount of buffered data for this channel. */
1.367 djm 2630: if (c->istate == CHAN_INPUT_OPEN ||
2631: c->istate == CHAN_INPUT_WAIT_DRAIN)
2632: channel_output_poll_input_open(ssh, c);
1.44 markus 2633: /* Send extended data, i.e. stderr */
1.358 djm 2634: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2635: c->extended_usage == CHAN_EXTENDED_READ)
2636: channel_output_poll_extended_read(ssh, c);
1.25 markus 2637: }
1.1 deraadt 2638: }
2639:
1.354 markus 2640: /* -- mux proxy support */
2641:
2642: /*
2643: * When multiplexing channel messages for mux clients we have to deal
2644: * with downstream messages from the mux client and upstream messages
2645: * from the ssh server:
2646: * 1) Handling downstream messages is straightforward and happens
2647: * in channel_proxy_downstream():
2648: * - We forward all messages (mostly) unmodified to the server.
2649: * - However, in order to route messages from upstream to the correct
2650: * downstream client, we have to replace the channel IDs used by the
2651: * mux clients with a unique channel ID because the mux clients might
2652: * use conflicting channel IDs.
2653: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2654: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2655: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2656: * with the newly allocated channel ID.
2657: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 2658: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 2659: * is then translated back to the original mux client ID.
2660: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2661: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2662: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2663: * downstream mux client are removed.
2664: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2665: * requires more work, because they are not addressed to a specific
2666: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2667: * out whether the request is addressed to the local client or a
2668: * specific downstream client based on the listen-address/port.
1.380 djm 2669: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 2670: * not supported as the matching session/channel cannot be identified
2671: * easily.
2672: */
2673:
2674: /*
2675: * receive packets from downstream mux clients:
2676: * channel callback fired on read from mux client, creates
2677: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2678: * on channel creation.
2679: */
2680: int
1.367 djm 2681: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2682: {
2683: Channel *c = NULL;
2684: struct sshbuf *original = NULL, *modified = NULL;
2685: const u_char *cp;
2686: char *ctype = NULL, *listen_host = NULL;
2687: u_char type;
2688: size_t have;
1.370 djm 2689: int ret = -1, r;
1.355 djm 2690: u_int id, remote_id, listen_port;
1.354 markus 2691:
1.367 djm 2692: /* sshbuf_dump(downstream->input, stderr); */
2693: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2694: != 0) {
2695: error("%s: malformed message: %s", __func__, ssh_err(r));
2696: return -1;
2697: }
2698: if (have < 2) {
2699: error("%s: short message", __func__);
2700: return -1;
2701: }
2702: type = cp[1];
2703: /* skip padlen + type */
2704: cp += 2;
2705: have -= 2;
2706: if (ssh_packet_log_type(type))
2707: debug3("%s: channel %u: down->up: type %u", __func__,
2708: downstream->self, type);
2709:
2710: switch (type) {
2711: case SSH2_MSG_CHANNEL_OPEN:
2712: if ((original = sshbuf_from(cp, have)) == NULL ||
2713: (modified = sshbuf_new()) == NULL) {
2714: error("%s: alloc", __func__);
2715: goto out;
2716: }
2717: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2718: (r = sshbuf_get_u32(original, &id)) != 0) {
2719: error("%s: parse error %s", __func__, ssh_err(r));
2720: goto out;
2721: }
1.367 djm 2722: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2723: -1, -1, -1, 0, 0, 0, ctype, 1);
2724: c->mux_ctx = downstream; /* point to mux client */
2725: c->mux_downstream_id = id; /* original downstream id */
2726: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2727: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2728: (r = sshbuf_putb(modified, original)) != 0) {
2729: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2730: channel_free(ssh, c);
1.354 markus 2731: goto out;
2732: }
2733: break;
2734: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2735: /*
2736: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2737: * need to parse 'remote_id' instead of 'ctype'.
2738: */
2739: if ((original = sshbuf_from(cp, have)) == NULL ||
2740: (modified = sshbuf_new()) == NULL) {
2741: error("%s: alloc", __func__);
2742: goto out;
2743: }
2744: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2745: (r = sshbuf_get_u32(original, &id)) != 0) {
2746: error("%s: parse error %s", __func__, ssh_err(r));
2747: goto out;
2748: }
1.367 djm 2749: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2750: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
2751: c->mux_ctx = downstream; /* point to mux client */
2752: c->mux_downstream_id = id;
2753: c->remote_id = remote_id;
1.368 djm 2754: c->have_remote_id = 1;
1.354 markus 2755: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2756: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2757: (r = sshbuf_putb(modified, original)) != 0) {
2758: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2759: channel_free(ssh, c);
1.354 markus 2760: goto out;
2761: }
2762: break;
2763: case SSH2_MSG_GLOBAL_REQUEST:
2764: if ((original = sshbuf_from(cp, have)) == NULL) {
2765: error("%s: alloc", __func__);
2766: goto out;
2767: }
2768: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
2769: error("%s: parse error %s", __func__, ssh_err(r));
2770: goto out;
2771: }
2772: if (strcmp(ctype, "tcpip-forward") != 0) {
2773: error("%s: unsupported request %s", __func__, ctype);
2774: goto out;
2775: }
2776: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2777: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2778: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
2779: error("%s: parse error %s", __func__, ssh_err(r));
2780: goto out;
2781: }
1.355 djm 2782: if (listen_port > 65535) {
2783: error("%s: tcpip-forward for %s: bad port %u",
2784: __func__, listen_host, listen_port);
2785: goto out;
2786: }
1.354 markus 2787: /* Record that connection to this host/port is permitted. */
1.381 djm 2788: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 2789: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 2790: listen_host = NULL;
2791: break;
2792: case SSH2_MSG_CHANNEL_CLOSE:
2793: if (have < 4)
2794: break;
2795: remote_id = PEEK_U32(cp);
1.367 djm 2796: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 2797: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 2798: channel_free(ssh, c);
1.354 markus 2799: else
2800: c->flags |= CHAN_CLOSE_SENT;
2801: }
2802: break;
2803: }
2804: if (modified) {
2805: if ((r = sshpkt_start(ssh, type)) != 0 ||
2806: (r = sshpkt_putb(ssh, modified)) != 0 ||
2807: (r = sshpkt_send(ssh)) != 0) {
2808: error("%s: send %s", __func__, ssh_err(r));
2809: goto out;
2810: }
2811: } else {
2812: if ((r = sshpkt_start(ssh, type)) != 0 ||
2813: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2814: (r = sshpkt_send(ssh)) != 0) {
2815: error("%s: send %s", __func__, ssh_err(r));
2816: goto out;
2817: }
2818: }
2819: ret = 0;
2820: out:
2821: free(ctype);
2822: free(listen_host);
2823: sshbuf_free(original);
2824: sshbuf_free(modified);
2825: return ret;
2826: }
2827:
2828: /*
2829: * receive packets from upstream server and de-multiplex packets
2830: * to correct downstream:
2831: * implemented as a helper for channel input handlers,
2832: * replaces local (proxy) channel ID with downstream channel ID.
2833: */
2834: int
1.363 markus 2835: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 2836: {
2837: struct sshbuf *b = NULL;
2838: Channel *downstream;
2839: const u_char *cp = NULL;
2840: size_t len;
2841: int r;
2842:
2843: /*
2844: * When receiving packets from the peer we need to check whether we
2845: * need to forward the packets to the mux client. In this case we
1.380 djm 2846: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 2847: * so we can cleanup the channel.
2848: */
2849: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2850: return 0;
2851: if ((downstream = c->mux_ctx) == NULL)
2852: return 0;
2853: switch (type) {
2854: case SSH2_MSG_CHANNEL_CLOSE:
2855: case SSH2_MSG_CHANNEL_DATA:
2856: case SSH2_MSG_CHANNEL_EOF:
2857: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2858: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2859: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2860: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2861: case SSH2_MSG_CHANNEL_SUCCESS:
2862: case SSH2_MSG_CHANNEL_FAILURE:
2863: case SSH2_MSG_CHANNEL_REQUEST:
2864: break;
2865: default:
2866: debug2("%s: channel %u: unsupported type %u", __func__,
2867: c->self, type);
2868: return 0;
2869: }
2870: if ((b = sshbuf_new()) == NULL) {
2871: error("%s: alloc reply", __func__);
2872: goto out;
2873: }
2874: /* get remaining payload (after id) */
2875: cp = sshpkt_ptr(ssh, &len);
2876: if (cp == NULL) {
2877: error("%s: no packet", __func__);
2878: goto out;
2879: }
2880: /* translate id and send to muxclient */
2881: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2882: (r = sshbuf_put_u8(b, type)) != 0 ||
2883: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2884: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 2885: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.354 markus 2886: error("%s: compose for muxclient %s", __func__, ssh_err(r));
2887: goto out;
2888: }
2889: /* sshbuf_dump(b, stderr); */
2890: if (ssh_packet_log_type(type))
2891: debug3("%s: channel %u: up->down: type %u", __func__, c->self,
2892: type);
2893: out:
2894: /* update state */
2895: switch (type) {
2896: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2897: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 2898: if (cp && len > 4) {
1.354 markus 2899: c->remote_id = PEEK_U32(cp);
1.368 djm 2900: c->have_remote_id = 1;
2901: }
1.354 markus 2902: break;
2903: case SSH2_MSG_CHANNEL_CLOSE:
2904: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 2905: channel_free(ssh, c);
1.354 markus 2906: else
2907: c->flags |= CHAN_CLOSE_RCVD;
2908: break;
2909: }
2910: sshbuf_free(b);
2911: return 1;
2912: }
1.121 markus 2913:
2914: /* -- protocol input */
1.249 djm 2915:
1.367 djm 2916: /* Parse a channel ID from the current packet */
2917: static int
2918: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
2919: {
2920: u_int32_t id;
2921: int r;
2922:
2923: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
2924: error("%s: parse id: %s", where, ssh_err(r));
2925: ssh_packet_disconnect(ssh, "Invalid %s message", what);
2926: }
2927: if (id > INT_MAX) {
2928: error("%s: bad channel id %u: %s", where, id, ssh_err(r));
2929: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
2930: }
2931: return (int)id;
2932: }
2933:
2934: /* Lookup a channel from an ID in the current packet */
2935: static Channel *
2936: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
2937: {
2938: int id = channel_parse_id(ssh, where, what);
2939: Channel *c;
2940:
2941: if ((c = channel_lookup(ssh, id)) == NULL) {
2942: ssh_packet_disconnect(ssh,
2943: "%s packet referred to nonexistent channel %d", what, id);
2944: }
2945: return c;
2946: }
2947:
1.339 markus 2948: int
1.363 markus 2949: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2950: {
1.332 djm 2951: const u_char *data;
1.367 djm 2952: size_t data_len, win_len;
2953: Channel *c = channel_from_packet_id(ssh, __func__, "data");
2954: int r;
1.25 markus 2955:
1.363 markus 2956: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2957: return 0;
1.25 markus 2958:
2959: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2960: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 2961: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
2962: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 2963: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2964: return 0;
1.37 markus 2965:
1.25 markus 2966: /* Get the data. */
1.367 djm 2967: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0)
2968: fatal("%s: channel %d: get data: %s", __func__,
2969: c->self, ssh_err(r));
2970: ssh_packet_check_eom(ssh);
2971:
1.309 djm 2972: win_len = data_len;
2973: if (c->datagram)
2974: win_len += 4; /* string length header */
1.200 markus 2975:
2976: /*
1.367 djm 2977: * The sending side reduces its window as it sends data, so we
2978: * must 'fake' consumption of the data in order to ensure that window
2979: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 2980: */
1.358 djm 2981: if (c->ostate != CHAN_OUTPUT_OPEN) {
2982: c->local_window -= win_len;
2983: c->local_consumed += win_len;
1.339 markus 2984: return 0;
1.200 markus 2985: }
1.41 markus 2986:
1.358 djm 2987: if (win_len > c->local_maxpacket) {
1.367 djm 2988: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 2989: c->self, win_len, c->local_maxpacket);
1.367 djm 2990: return 0;
1.358 djm 2991: }
2992: if (win_len > c->local_window) {
1.367 djm 2993: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 2994: c->self, win_len, c->local_window);
2995: return 0;
1.44 markus 2996: }
1.358 djm 2997: c->local_window -= win_len;
2998:
1.367 djm 2999: if (c->datagram) {
3000: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
3001: fatal("%s: channel %d: append datagram: %s",
3002: __func__, c->self, ssh_err(r));
3003: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
3004: fatal("%s: channel %d: append data: %s",
3005: __func__, c->self, ssh_err(r));
3006:
1.339 markus 3007: return 0;
1.1 deraadt 3008: }
1.121 markus 3009:
1.339 markus 3010: int
1.363 markus 3011: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 3012: {
1.367 djm 3013: const u_char *data;
3014: size_t data_len;
3015: u_int32_t tcode;
3016: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
3017: int r;
1.44 markus 3018:
1.363 markus 3019: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3020: return 0;
1.44 markus 3021: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 3022: logit("channel %d: ext data for non open", c->self);
1.339 markus 3023: return 0;
1.172 markus 3024: }
3025: if (c->flags & CHAN_EOF_RCVD) {
3026: if (datafellows & SSH_BUG_EXTEOF)
1.367 djm 3027: debug("channel %d: accepting ext data after eof",
3028: c->self);
1.172 markus 3029: else
1.367 djm 3030: ssh_packet_disconnect(ssh, "Received extended_data "
3031: "after EOF on channel %d.", c->self);
3032: }
3033:
3034: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
3035: error("%s: parse tcode: %s", __func__, ssh_err(r));
3036: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3037: }
3038: if (c->efd == -1 ||
3039: c->extended_usage != CHAN_EXTENDED_WRITE ||
3040: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3041: logit("channel %d: bad ext data", c->self);
1.339 markus 3042: return 0;
1.44 markus 3043: }
1.367 djm 3044: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0) {
3045: error("%s: parse data: %s", __func__, ssh_err(r));
3046: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3047: }
3048: ssh_packet_check_eom(ssh);
3049:
1.44 markus 3050: if (data_len > c->local_window) {
1.367 djm 3051: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3052: c->self, data_len, c->local_window);
1.339 markus 3053: return 0;
1.44 markus 3054: }
1.367 djm 3055: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3056: /* XXX sshpkt_getb? */
3057: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
3058: error("%s: append: %s", __func__, ssh_err(r));
1.44 markus 3059: c->local_window -= data_len;
1.339 markus 3060: return 0;
1.44 markus 3061: }
3062:
1.339 markus 3063: int
1.363 markus 3064: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3065: {
1.367 djm 3066: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
3067:
3068: ssh_packet_check_eom(ssh);
1.41 markus 3069:
1.363 markus 3070: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3071: return 0;
1.367 djm 3072: chan_rcvd_ieof(ssh, c);
1.133 markus 3073:
3074: /* XXX force input close */
1.156 markus 3075: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3076: debug("channel %d: FORCE input drain", c->self);
3077: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3078: if (sshbuf_len(c->input) == 0)
3079: chan_ibuf_empty(ssh, c);
1.133 markus 3080: }
1.339 markus 3081: return 0;
1.41 markus 3082: }
1.1 deraadt 3083:
1.339 markus 3084: int
1.363 markus 3085: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3086: {
1.367 djm 3087: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.151 markus 3088:
1.363 markus 3089: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3090: return 0;
1.367 djm 3091: ssh_packet_check_eom(ssh);
3092: chan_rcvd_oclose(ssh, c);
1.339 markus 3093: return 0;
1.1 deraadt 3094: }
3095:
1.339 markus 3096: int
1.363 markus 3097: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3098: {
1.367 djm 3099: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3100: u_int32_t remote_window, remote_maxpacket;
3101: int r;
1.25 markus 3102:
1.363 markus 3103: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3104: return 0;
3105: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 3106: packet_disconnect("Received open confirmation for "
1.367 djm 3107: "non-opening channel %d.", c->self);
3108: /*
3109: * Record the remote channel number and mark that the channel
3110: * is now open.
3111: */
1.368 djm 3112: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3113: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.367 djm 3114: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0) {
3115: error("%s: window/maxpacket: %s", __func__, ssh_err(r));
3116: packet_disconnect("Invalid open confirmation message");
3117: }
3118: ssh_packet_check_eom(ssh);
3119:
1.368 djm 3120: c->have_remote_id = 1;
1.367 djm 3121: c->remote_window = remote_window;
3122: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3123: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3124: if (c->open_confirm) {
1.367 djm 3125: debug2("%s: channel %d: callback start", __func__, c->self);
3126: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
3127: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3128: }
1.358 djm 3129: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3130: c->remote_window, c->remote_maxpacket);
1.339 markus 3131: return 0;
1.1 deraadt 3132: }
3133:
1.127 itojun 3134: static char *
1.114 markus 3135: reason2txt(int reason)
3136: {
1.143 deraadt 3137: switch (reason) {
1.114 markus 3138: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3139: return "administratively prohibited";
3140: case SSH2_OPEN_CONNECT_FAILED:
3141: return "connect failed";
3142: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3143: return "unknown channel type";
3144: case SSH2_OPEN_RESOURCE_SHORTAGE:
3145: return "resource shortage";
3146: }
1.117 stevesk 3147: return "unknown reason";
1.114 markus 3148: }
3149:
1.339 markus 3150: int
1.363 markus 3151: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3152: {
1.367 djm 3153: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3154: u_int32_t reason;
3155: char *msg = NULL;
3156: int r;
1.25 markus 3157:
1.363 markus 3158: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3159: return 0;
3160: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 3161: packet_disconnect("Received open failure for "
1.367 djm 3162: "non-opening channel %d.", c->self);
3163: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
3164: error("%s: reason: %s", __func__, ssh_err(r));
3165: packet_disconnect("Invalid open failure message");
3166: }
1.378 djm 3167: /* skip language */
3168: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
3169: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0) {
3170: error("%s: message/lang: %s", __func__, ssh_err(r));
3171: packet_disconnect("Invalid open failure message");
1.358 djm 3172: }
1.367 djm 3173: ssh_packet_check_eom(ssh);
3174: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3175: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3176: free(msg);
3177: if (c->open_confirm) {
1.367 djm 3178: debug2("%s: channel %d: callback start", __func__, c->self);
3179: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
3180: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3181: }
1.291 djm 3182: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3183: chan_mark_dead(ssh, c);
1.339 markus 3184: return 0;
1.44 markus 3185: }
3186:
1.339 markus 3187: int
1.363 markus 3188: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3189: {
1.367 djm 3190: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3191: Channel *c;
1.367 djm 3192: u_int32_t adjust;
3193: u_int new_rwin;
3194: int r;
1.1 deraadt 3195:
1.367 djm 3196: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3197: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3198: return 0;
1.372 markus 3199: }
1.367 djm 3200:
1.363 markus 3201: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3202: return 0;
1.367 djm 3203: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0) {
3204: error("%s: adjust: %s", __func__, ssh_err(r));
3205: packet_disconnect("Invalid window adjust message");
3206: }
3207: ssh_packet_check_eom(ssh);
3208: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3209: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3210: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3211: c->self, adjust, c->remote_window);
3212: }
3213: c->remote_window = new_rwin;
1.339 markus 3214: return 0;
1.121 markus 3215: }
1.1 deraadt 3216:
1.339 markus 3217: int
1.363 markus 3218: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3219: {
1.367 djm 3220: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3221: Channel *c;
3222: struct channel_confirm *cc;
3223:
3224: /* Reset keepalive timeout */
1.296 andreas 3225: packet_set_alive_timeouts(0);
1.275 djm 3226:
1.367 djm 3227: debug2("%s: type %d id %d", __func__, type, id);
1.275 djm 3228:
1.367 djm 3229: if ((c = channel_lookup(ssh, id)) == NULL) {
3230: logit("%s: %d: unknown", __func__, id);
1.339 markus 3231: return 0;
1.367 djm 3232: }
1.363 markus 3233: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3234: return 0;
1.367 djm 3235: ssh_packet_check_eom(ssh);
1.275 djm 3236: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3237: return 0;
1.367 djm 3238: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3239: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 3240: explicit_bzero(cc, sizeof(*cc));
1.321 djm 3241: free(cc);
1.339 markus 3242: return 0;
1.275 djm 3243: }
1.121 markus 3244:
3245: /* -- tcp forwarding */
1.135 markus 3246:
3247: void
1.367 djm 3248: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3249: {
1.367 djm 3250: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3251: }
1.121 markus 3252:
1.312 djm 3253:
3254: /*
3255: * Determine whether or not a port forward listens to loopback, the
3256: * specified address or wildcard. On the client, a specified bind
3257: * address will always override gateway_ports. On the server, a
3258: * gateway_ports of 1 (``yes'') will override the client's specification
3259: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3260: * will bind to whatever address the client asked for.
3261: *
3262: * Special-case listen_addrs are:
3263: *
3264: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3265: * "" (empty string), "*" -> wildcard v4/v6
3266: * "localhost" -> loopback v4/v6
1.334 djm 3267: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3268: */
3269: static const char *
3270: channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
1.336 millert 3271: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3272: {
3273: const char *addr = NULL;
3274: int wildcard = 0;
3275:
3276: if (listen_addr == NULL) {
3277: /* No address specified: default to gateway_ports setting */
1.336 millert 3278: if (fwd_opts->gateway_ports)
1.312 djm 3279: wildcard = 1;
1.336 millert 3280: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 3281: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
3282: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3283: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3284: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3285: wildcard = 1;
1.326 djm 3286: /*
3287: * Notify client if they requested a specific listen
3288: * address and it was overridden.
3289: */
3290: if (*listen_addr != '\0' &&
3291: strcmp(listen_addr, "0.0.0.0") != 0 &&
3292: strcmp(listen_addr, "*") != 0) {
3293: packet_send_debug("Forwarding listen address "
3294: "\"%s\" overridden by server "
3295: "GatewayPorts", listen_addr);
3296: }
1.334 djm 3297: } else if (strcmp(listen_addr, "localhost") != 0 ||
3298: strcmp(listen_addr, "127.0.0.1") == 0 ||
3299: strcmp(listen_addr, "::1") == 0) {
3300: /* Accept localhost address when GatewayPorts=yes */
3301: addr = listen_addr;
1.326 djm 3302: }
1.334 djm 3303: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3304: strcmp(listen_addr, "::1") == 0) {
3305: /*
3306: * If a specific IPv4/IPv6 localhost address has been
3307: * requested then accept it even if gateway_ports is in
3308: * effect. This allows the client to prefer IPv4 or IPv6.
3309: */
3310: addr = listen_addr;
1.312 djm 3311: }
3312: if (wildcardp != NULL)
3313: *wildcardp = wildcard;
3314: return addr;
3315: }
3316:
1.160 markus 3317: static int
1.367 djm 3318: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3319: struct Forward *fwd, int *allocated_listen_port,
3320: struct ForwardOptions *fwd_opts)
1.25 markus 3321: {
1.113 markus 3322: Channel *c;
1.226 djm 3323: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3324: struct addrinfo hints, *ai, *aitop;
1.212 djm 3325: const char *host, *addr;
1.35 markus 3326: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3327: in_port_t *lport_p;
1.25 markus 3328:
1.212 djm 3329: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3330:
1.344 millert 3331: if (is_client && fwd->connect_path != NULL) {
3332: host = fwd->connect_path;
3333: } else {
3334: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3335: fwd->listen_host : fwd->connect_host;
3336: if (host == NULL) {
3337: error("No forward host name.");
3338: return 0;
3339: }
3340: if (strlen(host) >= NI_MAXHOST) {
3341: error("Forward host name too long.");
3342: return 0;
3343: }
1.87 markus 3344: }
1.25 markus 3345:
1.312 djm 3346: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.336 millert 3347: addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard,
3348: is_client, fwd_opts);
3349: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 3350: type, wildcard, (addr == NULL) ? "NULL" : addr);
3351:
3352: /*
1.35 markus 3353: * getaddrinfo returns a loopback address if the hostname is
3354: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3355: */
1.35 markus 3356: memset(&hints, 0, sizeof(hints));
1.367 djm 3357: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3358: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3359: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3360: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3361: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3362: if (addr == NULL) {
3363: /* This really shouldn't happen */
3364: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 3365: ssh_gai_strerror(r));
1.212 djm 3366: } else {
1.336 millert 3367: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 3368: ssh_gai_strerror(r));
1.212 djm 3369: }
1.218 markus 3370: return 0;
1.212 djm 3371: }
1.295 djm 3372: if (allocated_listen_port != NULL)
3373: *allocated_listen_port = 0;
1.35 markus 3374: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3375: switch (ai->ai_family) {
3376: case AF_INET:
3377: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3378: sin_port;
3379: break;
3380: case AF_INET6:
3381: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3382: sin6_port;
3383: break;
3384: default:
1.35 markus 3385: continue;
1.295 djm 3386: }
3387: /*
3388: * If allocating a port for -R forwards, then use the
3389: * same port for all address families.
3390: */
1.367 djm 3391: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3392: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3393: *allocated_listen_port > 0)
1.295 djm 3394: *lport_p = htons(*allocated_listen_port);
3395:
1.35 markus 3396: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3397: strport, sizeof(strport),
3398: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 3399: error("%s: getnameinfo failed", __func__);
1.35 markus 3400: continue;
3401: }
3402: /* Create a port to listen for the host. */
1.300 dtucker 3403: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 3404: if (sock < 0) {
3405: /* this is no error since kernel may not support ipv6 */
1.377 djm 3406: verbose("socket [%s]:%s: %.100s", ntop, strport,
3407: strerror(errno));
1.35 markus 3408: continue;
3409: }
1.226 djm 3410:
1.376 djm 3411: set_reuseaddr(sock);
1.182 stevesk 3412:
1.295 djm 3413: debug("Local forwarding listening on %s port %s.",
3414: ntop, strport);
1.35 markus 3415:
3416: /* Bind the socket to the address. */
3417: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.367 djm 3418: /*
3419: * address can be in if use ipv6 address is
3420: * already bound
3421: */
1.377 djm 3422: verbose("bind [%s]:%s: %.100s",
3423: ntop, strport, strerror(errno));
1.35 markus 3424: close(sock);
3425: continue;
3426: }
3427: /* Start listening for connections on the socket. */
1.199 markus 3428: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.377 djm 3429: error("listen [%s]:%s: %.100s", ntop, strport,
3430: strerror(errno));
1.35 markus 3431: close(sock);
3432: continue;
3433: }
1.295 djm 3434:
3435: /*
1.336 millert 3436: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3437: * record what we got.
3438: */
1.367 djm 3439: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3440: fwd->listen_port == 0 &&
1.295 djm 3441: allocated_listen_port != NULL &&
3442: *allocated_listen_port == 0) {
1.350 djm 3443: *allocated_listen_port = get_local_port(sock);
1.295 djm 3444: debug("Allocated listen port %d",
3445: *allocated_listen_port);
3446: }
3447:
1.35 markus 3448: /* Allocate a channel number for the socket. */
1.367 djm 3449: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3450: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3451: 0, "port listener", 1);
1.293 djm 3452: c->path = xstrdup(host);
1.336 millert 3453: c->host_port = fwd->connect_port;
1.312 djm 3454: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3455: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 3456: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
3457: c->listening_port = *allocated_listen_port;
3458: else
1.336 millert 3459: c->listening_port = fwd->listen_port;
1.35 markus 3460: success = 1;
3461: }
3462: if (success == 0)
1.336 millert 3463: error("%s: cannot listen to port: %d", __func__,
3464: fwd->listen_port);
1.35 markus 3465: freeaddrinfo(aitop);
1.87 markus 3466: return success;
1.25 markus 3467: }
1.1 deraadt 3468:
1.336 millert 3469: static int
1.367 djm 3470: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3471: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3472: {
3473: struct sockaddr_un sunaddr;
3474: const char *path;
3475: Channel *c;
3476: int port, sock;
3477: mode_t omask;
3478:
3479: switch (type) {
3480: case SSH_CHANNEL_UNIX_LISTENER:
3481: if (fwd->connect_path != NULL) {
3482: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3483: error("Local connecting path too long: %s",
3484: fwd->connect_path);
3485: return 0;
3486: }
3487: path = fwd->connect_path;
3488: port = PORT_STREAMLOCAL;
3489: } else {
3490: if (fwd->connect_host == NULL) {
3491: error("No forward host name.");
3492: return 0;
3493: }
3494: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3495: error("Forward host name too long.");
3496: return 0;
3497: }
3498: path = fwd->connect_host;
3499: port = fwd->connect_port;
3500: }
3501: break;
3502: case SSH_CHANNEL_RUNIX_LISTENER:
3503: path = fwd->listen_path;
3504: port = PORT_STREAMLOCAL;
3505: break;
3506: default:
3507: error("%s: unexpected channel type %d", __func__, type);
3508: return 0;
3509: }
3510:
3511: if (fwd->listen_path == NULL) {
3512: error("No forward path name.");
3513: return 0;
3514: }
3515: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3516: error("Local listening path too long: %s", fwd->listen_path);
3517: return 0;
3518: }
3519:
3520: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
3521:
3522: /* Start a Unix domain listener. */
3523: omask = umask(fwd_opts->streamlocal_bind_mask);
3524: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3525: fwd_opts->streamlocal_bind_unlink);
3526: umask(omask);
3527: if (sock < 0)
3528: return 0;
3529:
3530: debug("Local forwarding listening on path %s.", fwd->listen_path);
3531:
3532: /* Allocate a channel number for the socket. */
1.367 djm 3533: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3534: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3535: 0, "unix listener", 1);
3536: c->path = xstrdup(path);
3537: c->host_port = port;
3538: c->listening_port = PORT_STREAMLOCAL;
3539: c->listening_addr = xstrdup(fwd->listen_path);
3540: return 1;
3541: }
3542:
3543: static int
1.367 djm 3544: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3545: const char *host, u_short port)
1.202 djm 3546: {
1.209 avsm 3547: u_int i;
3548: int found = 0;
1.202 djm 3549:
1.367 djm 3550: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3551: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3552: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3553: continue;
3554: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3555: debug2("%s: close channel %d", __func__, i);
1.367 djm 3556: channel_free(ssh, c);
1.312 djm 3557: found = 1;
3558: }
3559: }
3560:
1.367 djm 3561: return found;
1.312 djm 3562: }
3563:
1.336 millert 3564: static int
1.367 djm 3565: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3566: {
3567: u_int i;
3568: int found = 0;
3569:
1.367 djm 3570: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3571: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3572: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3573: continue;
3574: if (c->path == NULL)
3575: continue;
3576: if (strcmp(c->path, path) == 0) {
3577: debug2("%s: close channel %d", __func__, i);
1.367 djm 3578: channel_free(ssh, c);
1.336 millert 3579: found = 1;
3580: }
3581: }
3582:
1.367 djm 3583: return found;
1.336 millert 3584: }
3585:
1.312 djm 3586: int
1.367 djm 3587: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3588: {
1.367 djm 3589: if (fwd->listen_path != NULL) {
3590: return channel_cancel_rport_listener_streamlocal(ssh,
3591: fwd->listen_path);
3592: } else {
3593: return channel_cancel_rport_listener_tcpip(ssh,
3594: fwd->listen_host, fwd->listen_port);
3595: }
1.336 millert 3596: }
3597:
3598: static int
1.367 djm 3599: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3600: const char *lhost, u_short lport, int cport,
3601: struct ForwardOptions *fwd_opts)
1.312 djm 3602: {
3603: u_int i;
3604: int found = 0;
1.336 millert 3605: const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts);
1.202 djm 3606:
1.367 djm 3607: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3608: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3609: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3610: continue;
1.313 markus 3611: if (c->listening_port != lport)
1.312 djm 3612: continue;
1.313 markus 3613: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3614: /* skip dynamic forwardings */
3615: if (c->host_port == 0)
3616: continue;
3617: } else {
3618: if (c->host_port != cport)
3619: continue;
3620: }
1.312 djm 3621: if ((c->listening_addr == NULL && addr != NULL) ||
3622: (c->listening_addr != NULL && addr == NULL))
3623: continue;
3624: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3625: debug2("%s: close channel %d", __func__, i);
1.367 djm 3626: channel_free(ssh, c);
1.202 djm 3627: found = 1;
3628: }
3629: }
3630:
1.367 djm 3631: return found;
1.202 djm 3632: }
3633:
1.336 millert 3634: static int
1.367 djm 3635: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3636: {
3637: u_int i;
3638: int found = 0;
3639:
3640: if (path == NULL) {
3641: error("%s: no path specified.", __func__);
3642: return 0;
3643: }
3644:
1.367 djm 3645: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3646: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3647: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3648: continue;
3649: if (c->listening_addr == NULL)
3650: continue;
3651: if (strcmp(c->listening_addr, path) == 0) {
3652: debug2("%s: close channel %d", __func__, i);
1.367 djm 3653: channel_free(ssh, c);
1.336 millert 3654: found = 1;
3655: }
3656: }
3657:
1.367 djm 3658: return found;
1.336 millert 3659: }
3660:
3661: int
1.367 djm 3662: channel_cancel_lport_listener(struct ssh *ssh,
3663: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3664: {
1.367 djm 3665: if (fwd->listen_path != NULL) {
3666: return channel_cancel_lport_listener_streamlocal(ssh,
3667: fwd->listen_path);
3668: } else {
3669: return channel_cancel_lport_listener_tcpip(ssh,
3670: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3671: }
1.336 millert 3672: }
3673:
1.362 markus 3674: /* protocol local port fwd, used by ssh */
1.160 markus 3675: int
1.367 djm 3676: channel_setup_local_fwd_listener(struct ssh *ssh,
3677: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3678: {
1.336 millert 3679: if (fwd->listen_path != NULL) {
1.367 djm 3680: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3681: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3682: } else {
1.367 djm 3683: return channel_setup_fwd_listener_tcpip(ssh,
3684: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3685: }
1.160 markus 3686: }
3687:
1.381 djm 3688: /* Matches a remote forwarding permission against a requested forwarding */
3689: static int
3690: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
3691: {
3692: int ret;
3693: char *lhost;
3694:
3695: /* XXX add ACLs for streamlocal */
3696: if (fwd->listen_path != NULL)
3697: return 1;
3698:
3699: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
3700: return 0;
3701:
3702: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
3703: allowed_open->listen_port != fwd->listen_port)
3704: return 0;
3705:
3706: /* Match hostnames case-insensitively */
3707: lhost = xstrdup(fwd->listen_host);
3708: lowercase(lhost);
3709: ret = match_pattern(lhost, allowed_open->listen_host);
3710: free(lhost);
3711:
3712: return ret;
3713: }
3714:
3715: /* Checks whether a requested remote forwarding is permitted */
3716: static int
3717: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
3718: {
3719: struct ssh_channels *sc = ssh->chanctxt;
3720: struct permission_set *pset = &sc->remote_perms;
3721: u_int i, permit, permit_adm = 1;
3722: struct permission *perm;
3723:
3724: /* XXX apply GatewayPorts override before checking? */
3725:
3726: permit = pset->all_permitted;
3727: if (!permit) {
3728: for (i = 0; i < pset->num_permitted_user; i++) {
3729: perm = &pset->permitted_user[i];
3730: if (remote_open_match(perm, fwd)) {
3731: permit = 1;
3732: break;
3733: }
3734: }
3735: }
3736:
3737: if (pset->num_permitted_admin > 0) {
3738: permit_adm = 0;
3739: for (i = 0; i < pset->num_permitted_admin; i++) {
3740: perm = &pset->permitted_admin[i];
3741: if (remote_open_match(perm, fwd)) {
3742: permit_adm = 1;
3743: break;
3744: }
3745: }
3746: }
3747:
3748: return permit && permit_adm;
3749: }
3750:
1.160 markus 3751: /* protocol v2 remote port fwd, used by sshd */
3752: int
1.367 djm 3753: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3754: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3755: {
1.381 djm 3756: if (!check_rfwd_permission(ssh, fwd)) {
3757: packet_send_debug("port forwarding refused");
3758: return 0;
3759: }
1.336 millert 3760: if (fwd->listen_path != NULL) {
1.367 djm 3761: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3762: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3763: } else {
1.367 djm 3764: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 3765: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3766: fwd_opts);
3767: }
1.160 markus 3768: }
3769:
1.27 markus 3770: /*
1.312 djm 3771: * Translate the requested rfwd listen host to something usable for
3772: * this server.
3773: */
3774: static const char *
3775: channel_rfwd_bind_host(const char *listen_host)
3776: {
3777: if (listen_host == NULL) {
1.378 djm 3778: return "localhost";
1.312 djm 3779: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 3780: return "";
1.312 djm 3781: } else
3782: return listen_host;
3783: }
3784:
3785: /*
1.27 markus 3786: * Initiate forwarding of connections to port "port" on remote host through
3787: * the secure channel to host:port from local side.
1.315 markus 3788: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 3789: * channel_update_permission().
1.27 markus 3790: */
1.253 markus 3791: int
1.367 djm 3792: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 3793: {
1.367 djm 3794: int r, success = 0, idx = -1;
3795: char *host_to_connect, *listen_host, *listen_path;
3796: int port_to_connect, listen_port;
1.73 markus 3797:
1.25 markus 3798: /* Send the forward request to the remote side. */
1.358 djm 3799: if (fwd->listen_path != NULL) {
1.367 djm 3800: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3801: (r = sshpkt_put_cstring(ssh,
3802: "streamlocal-forward@openssh.com")) != 0 ||
3803: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3804: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3805: (r = sshpkt_send(ssh)) != 0 ||
3806: (r = ssh_packet_write_wait(ssh)) != 0)
3807: fatal("%s: request streamlocal: %s",
3808: __func__, ssh_err(r));
1.336 millert 3809: } else {
1.367 djm 3810: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3811: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
3812: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3813: (r = sshpkt_put_cstring(ssh,
3814: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
3815: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
3816: (r = sshpkt_send(ssh)) != 0 ||
3817: (r = ssh_packet_write_wait(ssh)) != 0)
3818: fatal("%s: request tcpip-forward: %s",
3819: __func__, ssh_err(r));
1.73 markus 3820: }
1.358 djm 3821: /* Assume that server accepts the request */
3822: success = 1;
1.73 markus 3823: if (success) {
1.305 djm 3824: /* Record that connection to this host/port is permitted. */
1.367 djm 3825: host_to_connect = listen_host = listen_path = NULL;
3826: port_to_connect = listen_port = 0;
1.336 millert 3827: if (fwd->connect_path != NULL) {
1.367 djm 3828: host_to_connect = xstrdup(fwd->connect_path);
3829: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 3830: } else {
1.367 djm 3831: host_to_connect = xstrdup(fwd->connect_host);
3832: port_to_connect = fwd->connect_port;
1.336 millert 3833: }
3834: if (fwd->listen_path != NULL) {
1.367 djm 3835: listen_path = xstrdup(fwd->listen_path);
3836: listen_port = PORT_STREAMLOCAL;
1.336 millert 3837: } else {
1.367 djm 3838: if (fwd->listen_host != NULL)
3839: listen_host = xstrdup(fwd->listen_host);
3840: listen_port = fwd->listen_port;
3841: }
1.381 djm 3842: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 3843: host_to_connect, port_to_connect,
3844: listen_host, listen_path, listen_port, NULL);
1.44 markus 3845: }
1.367 djm 3846: return idx;
1.1 deraadt 3847: }
3848:
1.333 markus 3849: static int
1.381 djm 3850: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 3851: int requestedport)
1.333 markus 3852: {
3853: if (allowed_open->host_to_connect == NULL)
3854: return 0;
3855: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3856: allowed_open->port_to_connect != requestedport)
3857: return 0;
1.351 dtucker 3858: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3859: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3860: return 0;
3861: return 1;
3862: }
3863:
3864: /*
1.336 millert 3865: * Note that in the listen host/port case
1.333 markus 3866: * we don't support FWD_PERMIT_ANY_PORT and
3867: * need to translate between the configured-host (listen_host)
3868: * and what we've sent to the remote server (channel_rfwd_bind_host)
3869: */
3870: static int
1.381 djm 3871: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 3872: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3873: {
3874: const char *allowed_host;
3875:
3876: if (allowed_open->host_to_connect == NULL)
3877: return 0;
3878: if (allowed_open->listen_port != requestedport)
3879: return 0;
1.335 djm 3880: if (!translate && allowed_open->listen_host == NULL &&
3881: requestedhost == NULL)
3882: return 1;
1.333 markus 3883: allowed_host = translate ?
3884: channel_rfwd_bind_host(allowed_open->listen_host) :
3885: allowed_open->listen_host;
1.382 djm 3886: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 3887: strcmp(allowed_host, requestedhost) != 0)
3888: return 0;
3889: return 1;
3890: }
3891:
1.336 millert 3892: static int
1.381 djm 3893: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 3894: const char *requestedpath)
3895: {
3896: if (allowed_open->host_to_connect == NULL)
3897: return 0;
3898: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3899: return 0;
3900: if (allowed_open->listen_path == NULL ||
3901: strcmp(allowed_open->listen_path, requestedpath) != 0)
3902: return 0;
3903: return 1;
3904: }
3905:
1.27 markus 3906: /*
1.208 deraadt 3907: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3908: * local side.
3909: */
1.336 millert 3910: static int
1.367 djm 3911: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
3912: const char *host, u_short port)
1.202 djm 3913: {
1.367 djm 3914: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 3915: struct permission_set *pset = &sc->local_perms;
1.367 djm 3916: int r;
3917: u_int i;
1.381 djm 3918: struct permission *perm;
1.202 djm 3919:
1.381 djm 3920: for (i = 0; i < pset->num_permitted_user; i++) {
3921: perm = &pset->permitted_user[i];
3922: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 3923: break;
1.381 djm 3924: perm = NULL;
1.202 djm 3925: }
1.381 djm 3926: if (perm == NULL) {
1.202 djm 3927: debug("%s: requested forward not found", __func__);
1.312 djm 3928: return -1;
1.202 djm 3929: }
1.367 djm 3930: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3931: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
3932: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3933: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
3934: (r = sshpkt_put_u32(ssh, port)) != 0 ||
3935: (r = sshpkt_send(ssh)) != 0)
3936: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3937:
1.381 djm 3938: fwd_perm_clear(perm); /* unregister */
1.336 millert 3939:
3940: return 0;
3941: }
3942:
3943: /*
3944: * Request cancellation of remote forwarding of Unix domain socket
3945: * path from local side.
3946: */
3947: static int
1.367 djm 3948: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3949: {
1.367 djm 3950: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 3951: struct permission_set *pset = &sc->local_perms;
1.367 djm 3952: int r;
3953: u_int i;
1.381 djm 3954: struct permission *perm;
1.336 millert 3955:
1.381 djm 3956: for (i = 0; i < pset->num_permitted_user; i++) {
3957: perm = &pset->permitted_user[i];
3958: if (open_listen_match_streamlocal(perm, path))
1.336 millert 3959: break;
1.381 djm 3960: perm = NULL;
1.336 millert 3961: }
1.381 djm 3962: if (perm == NULL) {
1.336 millert 3963: debug("%s: requested forward not found", __func__);
3964: return -1;
3965: }
1.367 djm 3966: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3967: (r = sshpkt_put_cstring(ssh,
3968: "cancel-streamlocal-forward@openssh.com")) != 0 ||
3969: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3970: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
3971: (r = sshpkt_send(ssh)) != 0)
3972: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3973:
1.381 djm 3974: fwd_perm_clear(perm); /* unregister */
1.312 djm 3975:
3976: return 0;
1.202 djm 3977: }
3978:
3979: /*
1.336 millert 3980: * Request cancellation of remote forwarding of a connection from local side.
3981: */
3982: int
1.367 djm 3983: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3984: {
3985: if (fwd->listen_path != NULL) {
1.367 djm 3986: return channel_request_rforward_cancel_streamlocal(ssh,
3987: fwd->listen_path);
1.336 millert 3988: } else {
1.367 djm 3989: return channel_request_rforward_cancel_tcpip(ssh,
3990: fwd->listen_host,
3991: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 3992: }
1.1 deraadt 3993: }
3994:
1.99 markus 3995: /*
1.381 djm 3996: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 3997: * usually called by the server, because the user could connect to any port
3998: * anyway, and the server has no way to know but to trust the client anyway.
3999: */
4000: void
1.381 djm 4001: channel_permit_all(struct ssh *ssh, int where)
4002: {
4003: struct permission_set *pset = permission_set_get(ssh, where);
4004:
4005: if (pset->num_permitted_user == 0)
4006: pset->all_permitted = 1;
4007: }
4008:
4009: /*
4010: * Permit the specified host/port for forwarding.
4011: */
4012: void
4013: channel_add_permission(struct ssh *ssh, int who, int where,
4014: char *host, int port)
4015: {
4016: int local = where == FORWARD_LOCAL;
4017: struct permission_set *pset = permission_set_get(ssh, where);
4018:
4019: debug("allow %s forwarding to host %s port %d",
4020: fwd_ident(who, where), host, port);
4021: /*
4022: * Remote forwards set listen_host/port, local forwards set
4023: * host/port_to_connect.
4024: */
4025: permission_set_add(ssh, who, where,
4026: local ? host : 0, local ? port : 0,
4027: local ? NULL : host, NULL, local ? 0 : port, NULL);
4028: pset->all_permitted = 0;
4029: }
4030:
4031: /*
4032: * Administratively disable forwarding.
4033: */
4034: void
4035: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4036: {
1.381 djm 4037: channel_clear_permission(ssh, FORWARD_ADM, where);
4038: permission_set_add(ssh, FORWARD_ADM, where,
4039: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4040: }
4041:
1.381 djm 4042: /*
4043: * Clear a list of permitted opens.
4044: */
1.101 markus 4045: void
1.381 djm 4046: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4047: {
1.381 djm 4048: struct permission **permp;
4049: u_int *npermp;
1.367 djm 4050:
1.381 djm 4051: permission_set_get_array(ssh, who, where, &permp, &npermp);
4052: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4053: *npermp = 0;
1.315 markus 4054: }
4055:
4056: /*
4057: * Update the listen port for a dynamic remote forward, after
4058: * the actual 'newport' has been allocated. If 'newport' < 0 is
4059: * passed then they entry will be invalidated.
4060: */
4061: void
1.381 djm 4062: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4063: {
1.381 djm 4064: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4065:
1.381 djm 4066: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
4067: debug("%s: index out of range: %d num_permitted_user %d",
4068: __func__, idx, pset->num_permitted_user);
1.315 markus 4069: return;
4070: }
4071: debug("%s allowed port %d for forwarding to host %s port %d",
4072: newport > 0 ? "Updating" : "Removing",
4073: newport,
1.381 djm 4074: pset->permitted_user[idx].host_to_connect,
4075: pset->permitted_user[idx].port_to_connect);
1.367 djm 4076: if (newport <= 0)
1.381 djm 4077: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4078: else {
1.381 djm 4079: pset->permitted_user[idx].listen_port =
1.315 markus 4080: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
4081: }
1.99 markus 4082: }
4083:
1.314 dtucker 4084: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4085: int
4086: permitopen_port(const char *p)
4087: {
4088: int port;
4089:
4090: if (strcmp(p, "*") == 0)
4091: return FWD_PERMIT_ANY_PORT;
4092: if ((port = a2port(p)) > 0)
4093: return port;
4094: return -1;
4095: }
4096:
1.276 djm 4097: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4098: static int
1.276 djm 4099: connect_next(struct channel_connect *cctx)
1.41 markus 4100: {
1.276 djm 4101: int sock, saved_errno;
1.336 millert 4102: struct sockaddr_un *sunaddr;
1.367 djm 4103: char ntop[NI_MAXHOST];
4104: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4105:
1.276 djm 4106: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4107: switch (cctx->ai->ai_family) {
4108: case AF_UNIX:
4109: /* unix:pathname instead of host:port */
4110: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4111: strlcpy(ntop, "unix", sizeof(ntop));
4112: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4113: break;
4114: case AF_INET:
4115: case AF_INET6:
4116: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4117: ntop, sizeof(ntop), strport, sizeof(strport),
4118: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
4119: error("connect_next: getnameinfo failed");
4120: continue;
4121: }
4122: break;
4123: default:
1.41 markus 4124: continue;
4125: }
1.300 dtucker 4126: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4127: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4128: if (cctx->ai->ai_next == NULL)
1.186 djm 4129: error("socket: %.100s", strerror(errno));
4130: else
4131: verbose("socket: %.100s", strerror(errno));
1.41 markus 4132: continue;
4133: }
1.205 djm 4134: if (set_nonblock(sock) == -1)
4135: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 4136: if (connect(sock, cctx->ai->ai_addr,
4137: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
4138: debug("connect_next: host %.100s ([%.100s]:%s): "
4139: "%.100s", cctx->host, ntop, strport,
1.41 markus 4140: strerror(errno));
1.276 djm 4141: saved_errno = errno;
1.41 markus 4142: close(sock);
1.276 djm 4143: errno = saved_errno;
1.89 stevesk 4144: continue; /* fail -- try next */
1.41 markus 4145: }
1.336 millert 4146: if (cctx->ai->ai_family != AF_UNIX)
4147: set_nodelay(sock);
1.276 djm 4148: debug("connect_next: host %.100s ([%.100s]:%s) "
4149: "in progress, fd=%d", cctx->host, ntop, strport, sock);
4150: cctx->ai = cctx->ai->ai_next;
4151: return sock;
4152: }
4153: return -1;
4154: }
1.41 markus 4155:
1.276 djm 4156: static void
4157: channel_connect_ctx_free(struct channel_connect *cctx)
4158: {
1.321 djm 4159: free(cctx->host);
1.336 millert 4160: if (cctx->aitop) {
4161: if (cctx->aitop->ai_family == AF_UNIX)
4162: free(cctx->aitop);
4163: else
4164: freeaddrinfo(cctx->aitop);
4165: }
1.329 tedu 4166: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4167: }
4168:
1.357 dtucker 4169: /*
1.372 markus 4170: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4171: * passing back the failure reason if appropriate.
4172: */
1.372 markus 4173: static int
4174: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4175: char *ctype, char *rname, struct channel_connect *cctx,
4176: int *reason, const char **errmsg)
1.276 djm 4177: {
4178: struct addrinfo hints;
4179: int gaierr;
4180: int sock = -1;
4181: char strport[NI_MAXSERV];
1.336 millert 4182:
4183: if (port == PORT_STREAMLOCAL) {
4184: struct sockaddr_un *sunaddr;
4185: struct addrinfo *ai;
4186:
4187: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4188: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4189: return -1;
1.336 millert 4190: }
4191:
4192: /*
4193: * Fake up a struct addrinfo for AF_UNIX connections.
4194: * channel_connect_ctx_free() must check ai_family
4195: * and use free() not freeaddirinfo() for AF_UNIX.
4196: */
4197: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4198: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4199: ai->ai_addr = (struct sockaddr *)(ai + 1);
4200: ai->ai_addrlen = sizeof(*sunaddr);
4201: ai->ai_family = AF_UNIX;
1.372 markus 4202: ai->ai_socktype = socktype;
1.336 millert 4203: ai->ai_protocol = PF_UNSPEC;
4204: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4205: sunaddr->sun_family = AF_UNIX;
4206: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4207: cctx->aitop = ai;
1.336 millert 4208: } else {
4209: memset(&hints, 0, sizeof(hints));
1.367 djm 4210: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4211: hints.ai_socktype = socktype;
1.336 millert 4212: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4213: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4214: != 0) {
4215: if (errmsg != NULL)
4216: *errmsg = ssh_gai_strerror(gaierr);
4217: if (reason != NULL)
4218: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4219: error("connect_to %.100s: unknown host (%s)", name,
4220: ssh_gai_strerror(gaierr));
1.372 markus 4221: return -1;
1.336 millert 4222: }
1.41 markus 4223: }
1.276 djm 4224:
1.372 markus 4225: cctx->host = xstrdup(name);
4226: cctx->port = port;
4227: cctx->ai = cctx->aitop;
1.276 djm 4228:
1.372 markus 4229: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4230: error("connect to %.100s port %d failed: %s",
1.336 millert 4231: name, port, strerror(errno));
1.372 markus 4232: return -1;
4233: }
4234:
4235: return sock;
4236: }
4237:
4238: /* Return CONNECTING channel to remote host:port or local socket path */
4239: static Channel *
4240: connect_to(struct ssh *ssh, const char *host, int port,
4241: char *ctype, char *rname)
4242: {
4243: struct channel_connect cctx;
4244: Channel *c;
4245: int sock;
4246:
4247: memset(&cctx, 0, sizeof(cctx));
4248: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4249: &cctx, NULL, NULL);
4250: if (sock == -1) {
1.276 djm 4251: channel_connect_ctx_free(&cctx);
4252: return NULL;
1.41 markus 4253: }
1.367 djm 4254: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4255: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4256: c->host_port = port;
4257: c->path = xstrdup(host);
1.276 djm 4258: c->connect_ctx = cctx;
1.372 markus 4259:
1.276 djm 4260: return c;
1.41 markus 4261: }
1.99 markus 4262:
1.354 markus 4263: /*
4264: * returns either the newly connected channel or the downstream channel
4265: * that needs to deal with this connection.
4266: */
1.276 djm 4267: Channel *
1.367 djm 4268: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4269: u_short listen_port, char *ctype, char *rname)
1.73 markus 4270: {
1.367 djm 4271: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4272: struct permission_set *pset = &sc->local_perms;
1.367 djm 4273: u_int i;
1.381 djm 4274: struct permission *perm;
1.99 markus 4275:
1.381 djm 4276: for (i = 0; i < pset->num_permitted_user; i++) {
4277: perm = &pset->permitted_user[i];
4278: if (open_listen_match_tcpip(perm,
4279: listen_host, listen_port, 1)) {
4280: if (perm->downstream)
4281: return perm->downstream;
4282: if (perm->port_to_connect == 0)
1.372 markus 4283: return rdynamic_connect_prepare(ssh,
4284: ctype, rname);
1.367 djm 4285: return connect_to(ssh,
1.381 djm 4286: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4287: ctype, rname);
1.276 djm 4288: }
4289: }
1.74 markus 4290: error("WARNING: Server requests forwarding for unknown listen_port %d",
4291: listen_port);
1.276 djm 4292: return NULL;
1.73 markus 4293: }
4294:
1.336 millert 4295: Channel *
1.367 djm 4296: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4297: char *ctype, char *rname)
1.336 millert 4298: {
1.367 djm 4299: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4300: struct permission_set *pset = &sc->local_perms;
1.367 djm 4301: u_int i;
1.381 djm 4302: struct permission *perm;
1.336 millert 4303:
1.381 djm 4304: for (i = 0; i < pset->num_permitted_user; i++) {
4305: perm = &pset->permitted_user[i];
4306: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4307: return connect_to(ssh,
1.381 djm 4308: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4309: ctype, rname);
1.336 millert 4310: }
4311: }
4312: error("WARNING: Server requests forwarding for unknown path %.100s",
4313: path);
4314: return NULL;
4315: }
4316:
1.99 markus 4317: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4318: Channel *
1.367 djm 4319: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4320: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4321: {
1.367 djm 4322: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4323: struct permission_set *pset = &sc->local_perms;
1.372 markus 4324: struct channel_connect cctx;
4325: Channel *c;
1.367 djm 4326: u_int i, permit, permit_adm = 1;
1.372 markus 4327: int sock;
1.381 djm 4328: struct permission *perm;
1.99 markus 4329:
1.381 djm 4330: permit = pset->all_permitted;
1.99 markus 4331: if (!permit) {
1.381 djm 4332: for (i = 0; i < pset->num_permitted_user; i++) {
4333: perm = &pset->permitted_user[i];
4334: if (open_match(perm, host, port)) {
1.99 markus 4335: permit = 1;
1.333 markus 4336: break;
4337: }
1.367 djm 4338: }
1.257 dtucker 4339: }
1.99 markus 4340:
1.381 djm 4341: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4342: permit_adm = 0;
1.381 djm 4343: for (i = 0; i < pset->num_permitted_admin; i++) {
4344: perm = &pset->permitted_admin[i];
4345: if (open_match(perm, host, port)) {
1.257 dtucker 4346: permit_adm = 1;
1.333 markus 4347: break;
4348: }
1.367 djm 4349: }
1.99 markus 4350: }
1.257 dtucker 4351:
4352: if (!permit || !permit_adm) {
1.188 itojun 4353: logit("Received request to connect to host %.100s port %d, "
1.99 markus 4354: "but the request was denied.", host, port);
1.357 dtucker 4355: if (reason != NULL)
4356: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4357: return NULL;
1.99 markus 4358: }
1.372 markus 4359:
4360: memset(&cctx, 0, sizeof(cctx));
4361: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4362: &cctx, reason, errmsg);
4363: if (sock == -1) {
4364: channel_connect_ctx_free(&cctx);
4365: return NULL;
4366: }
4367:
4368: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4369: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4370: c->host_port = port;
4371: c->path = xstrdup(host);
4372: c->connect_ctx = cctx;
4373:
4374: return c;
1.336 millert 4375: }
4376:
4377: /* Check if connecting to that path is permitted and connect. */
4378: Channel *
1.367 djm 4379: channel_connect_to_path(struct ssh *ssh, const char *path,
4380: char *ctype, char *rname)
1.336 millert 4381: {
1.367 djm 4382: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4383: struct permission_set *pset = &sc->local_perms;
1.367 djm 4384: u_int i, permit, permit_adm = 1;
1.381 djm 4385: struct permission *perm;
1.336 millert 4386:
1.381 djm 4387: permit = pset->all_permitted;
1.336 millert 4388: if (!permit) {
1.381 djm 4389: for (i = 0; i < pset->num_permitted_user; i++) {
4390: perm = &pset->permitted_user[i];
4391: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4392: permit = 1;
4393: break;
4394: }
1.367 djm 4395: }
1.336 millert 4396: }
4397:
1.381 djm 4398: if (pset->num_permitted_admin > 0) {
1.336 millert 4399: permit_adm = 0;
1.381 djm 4400: for (i = 0; i < pset->num_permitted_admin; i++) {
4401: perm = &pset->permitted_admin[i];
4402: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4403: permit_adm = 1;
4404: break;
4405: }
1.367 djm 4406: }
1.336 millert 4407: }
4408:
4409: if (!permit || !permit_adm) {
4410: logit("Received request to connect to path %.100s, "
4411: "but the request was denied.", path);
4412: return NULL;
4413: }
1.367 djm 4414: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4415: }
4416:
4417: void
1.367 djm 4418: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4419: {
1.367 djm 4420: struct ssh_channels *sc = ssh->chanctxt;
4421: struct winsize ws;
4422: int r;
1.209 avsm 4423: u_int i;
1.204 djm 4424:
1.367 djm 4425: for (i = 0; i < sc->channels_alloc; i++) {
4426: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4427: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4428: continue;
1.367 djm 4429: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
1.204 djm 4430: continue;
1.367 djm 4431: channel_request_start(ssh, i, "window-change", 0);
4432: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4433: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4434: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4435: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4436: (r = sshpkt_send(ssh)) != 0)
4437: fatal("%s: channel %u: send window-change: %s",
4438: __func__, i, ssh_err(r));
1.204 djm 4439: }
1.372 markus 4440: }
4441:
4442: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4443: static Channel *
4444: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4445: {
4446: Channel *c;
4447: int r;
4448:
4449: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4450: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4451: c->host_port = 0;
4452: c->path = NULL;
4453:
4454: /*
4455: * We need to open the channel before we have a FD,
4456: * so that we can get SOCKS header from peer.
4457: */
4458: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4459: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4460: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4461: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
4462: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
4463: fatal("%s: channel %i: confirm: %s", __func__,
4464: c->self, ssh_err(r));
4465: }
4466: return c;
4467: }
4468:
4469: /* Return CONNECTING socket to remote host:port or local socket path */
4470: static int
4471: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4472: {
4473: struct channel_connect cctx;
4474: int sock;
4475:
4476: memset(&cctx, 0, sizeof(cctx));
4477: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4478: NULL, &cctx, NULL, NULL);
4479: if (sock == -1)
4480: channel_connect_ctx_free(&cctx);
4481: else {
4482: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4483: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4484: c->connect_ctx = cctx;
4485: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4486: }
4487: return sock;
1.99 markus 4488: }
4489:
1.121 markus 4490: /* -- X11 forwarding */
1.1 deraadt 4491:
1.27 markus 4492: /*
4493: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4494: * Returns 0 and a suitable display number for the DISPLAY variable
4495: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4496: */
1.141 stevesk 4497: int
1.367 djm 4498: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4499: int x11_use_localhost, int single_connection,
4500: u_int *display_numberp, int **chanids)
1.1 deraadt 4501: {
1.149 markus 4502: Channel *nc = NULL;
1.31 markus 4503: int display_number, sock;
4504: u_short port;
1.35 markus 4505: struct addrinfo hints, *ai, *aitop;
4506: char strport[NI_MAXSERV];
4507: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4508:
1.224 markus 4509: if (chanids == NULL)
4510: return -1;
4511:
1.33 markus 4512: for (display_number = x11_display_offset;
1.148 deraadt 4513: display_number < MAX_DISPLAYS;
4514: display_number++) {
1.25 markus 4515: port = 6000 + display_number;
1.35 markus 4516: memset(&hints, 0, sizeof(hints));
1.367 djm 4517: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4518: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4519: hints.ai_socktype = SOCK_STREAM;
4520: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4521: if ((gaierr = getaddrinfo(NULL, strport,
4522: &hints, &aitop)) != 0) {
1.271 dtucker 4523: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4524: return -1;
1.25 markus 4525: }
1.35 markus 4526: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4527: if (ai->ai_family != AF_INET &&
4528: ai->ai_family != AF_INET6)
1.35 markus 4529: continue;
1.300 dtucker 4530: sock = socket(ai->ai_family, ai->ai_socktype,
4531: ai->ai_protocol);
1.35 markus 4532: if (sock < 0) {
4533: error("socket: %.100s", strerror(errno));
1.203 markus 4534: freeaddrinfo(aitop);
1.141 stevesk 4535: return -1;
1.35 markus 4536: }
1.376 djm 4537: set_reuseaddr(sock);
1.35 markus 4538: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.367 djm 4539: debug2("%s: bind port %d: %.100s", __func__,
4540: port, strerror(errno));
1.35 markus 4541: close(sock);
1.367 djm 4542: for (n = 0; n < num_socks; n++)
1.35 markus 4543: close(socks[n]);
4544: num_socks = 0;
4545: break;
4546: }
4547: socks[num_socks++] = sock;
4548: if (num_socks == NUM_SOCKS)
4549: break;
1.25 markus 4550: }
1.83 stevesk 4551: freeaddrinfo(aitop);
1.35 markus 4552: if (num_socks > 0)
4553: break;
1.25 markus 4554: }
4555: if (display_number >= MAX_DISPLAYS) {
4556: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4557: return -1;
1.25 markus 4558: }
4559: /* Start listening for connections on the socket. */
1.35 markus 4560: for (n = 0; n < num_socks; n++) {
4561: sock = socks[n];
1.199 markus 4562: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 4563: error("listen: %.100s", strerror(errno));
4564: close(sock);
1.141 stevesk 4565: return -1;
1.35 markus 4566: }
1.25 markus 4567: }
1.35 markus 4568:
4569: /* Allocate a channel for each socket. */
1.242 djm 4570: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4571: for (n = 0; n < num_socks; n++) {
4572: sock = socks[n];
1.367 djm 4573: nc = channel_new(ssh, "x11 listener",
1.51 markus 4574: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4575: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4576: 0, "X11 inet listener", 1);
1.167 markus 4577: nc->single_connection = single_connection;
1.224 markus 4578: (*chanids)[n] = nc->self;
1.35 markus 4579: }
1.224 markus 4580: (*chanids)[n] = -1;
1.1 deraadt 4581:
1.141 stevesk 4582: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4583: *display_numberp = display_number;
1.367 djm 4584: return 0;
1.1 deraadt 4585: }
4586:
1.127 itojun 4587: static int
1.77 markus 4588: connect_local_xsocket(u_int dnr)
1.1 deraadt 4589: {
1.25 markus 4590: int sock;
4591: struct sockaddr_un addr;
4592:
1.147 stevesk 4593: sock = socket(AF_UNIX, SOCK_STREAM, 0);
4594: if (sock < 0)
4595: error("socket: %.100s", strerror(errno));
4596: memset(&addr, 0, sizeof(addr));
4597: addr.sun_family = AF_UNIX;
4598: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4599: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4600: return sock;
4601: close(sock);
1.25 markus 4602: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4603: return -1;
1.1 deraadt 4604: }
4605:
1.51 markus 4606: int
1.367 djm 4607: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4608: {
1.248 deraadt 4609: u_int display_number;
1.25 markus 4610: const char *display;
1.51 markus 4611: char buf[1024], *cp;
1.35 markus 4612: struct addrinfo hints, *ai, *aitop;
4613: char strport[NI_MAXSERV];
1.248 deraadt 4614: int gaierr, sock = 0;
1.25 markus 4615:
4616: /* Try to open a socket for the local X server. */
4617: display = getenv("DISPLAY");
4618: if (!display) {
4619: error("DISPLAY not set.");
1.51 markus 4620: return -1;
1.25 markus 4621: }
1.27 markus 4622: /*
4623: * Now we decode the value of the DISPLAY variable and make a
4624: * connection to the real X server.
4625: */
4626:
4627: /*
4628: * Check if it is a unix domain socket. Unix domain displays are in
4629: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4630: */
1.25 markus 4631: if (strncmp(display, "unix:", 5) == 0 ||
4632: display[0] == ':') {
4633: /* Connect to the unix domain socket. */
1.367 djm 4634: if (sscanf(strrchr(display, ':') + 1, "%u",
4635: &display_number) != 1) {
4636: error("Could not parse display number from DISPLAY: "
4637: "%.100s", display);
1.51 markus 4638: return -1;
1.25 markus 4639: }
4640: /* Create a socket. */
4641: sock = connect_local_xsocket(display_number);
4642: if (sock < 0)
1.51 markus 4643: return -1;
1.25 markus 4644:
4645: /* OK, we now have a connection to the display. */
1.51 markus 4646: return sock;
1.25 markus 4647: }
1.27 markus 4648: /*
4649: * Connect to an inet socket. The DISPLAY value is supposedly
4650: * hostname:d[.s], where hostname may also be numeric IP address.
4651: */
1.145 stevesk 4652: strlcpy(buf, display, sizeof(buf));
1.25 markus 4653: cp = strchr(buf, ':');
4654: if (!cp) {
4655: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4656: return -1;
1.25 markus 4657: }
4658: *cp = 0;
1.367 djm 4659: /*
4660: * buf now contains the host name. But first we parse the
4661: * display number.
4662: */
1.248 deraadt 4663: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4664: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4665: display);
1.51 markus 4666: return -1;
1.25 markus 4667: }
1.35 markus 4668:
4669: /* Look up the host address */
4670: memset(&hints, 0, sizeof(hints));
1.367 djm 4671: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4672: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4673: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4674: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4675: error("%.100s: unknown host. (%s)", buf,
4676: ssh_gai_strerror(gaierr));
1.51 markus 4677: return -1;
1.25 markus 4678: }
1.35 markus 4679: for (ai = aitop; ai; ai = ai->ai_next) {
4680: /* Create a socket. */
1.300 dtucker 4681: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 4682: if (sock < 0) {
1.194 markus 4683: debug2("socket: %.100s", strerror(errno));
1.41 markus 4684: continue;
4685: }
4686: /* Connect it to the display. */
4687: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 4688: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4689: 6000 + display_number, strerror(errno));
4690: close(sock);
4691: continue;
4692: }
4693: /* Success */
4694: break;
1.35 markus 4695: }
4696: freeaddrinfo(aitop);
4697: if (!ai) {
1.367 djm 4698: error("connect %.100s port %u: %.100s", buf,
4699: 6000 + display_number, strerror(errno));
1.51 markus 4700: return -1;
1.25 markus 4701: }
1.162 stevesk 4702: set_nodelay(sock);
1.51 markus 4703: return sock;
4704: }
4705:
4706: /*
1.27 markus 4707: * Requests forwarding of X11 connections, generates fake authentication
4708: * data, and enables authentication spoofing.
1.121 markus 4709: * This should be called in the client only.
1.27 markus 4710: */
1.49 markus 4711: void
1.367 djm 4712: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4713: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4714: {
1.367 djm 4715: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4716: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4717: u_int i, value;
1.367 djm 4718: const char *cp;
1.25 markus 4719: char *new_data;
1.367 djm 4720: int r, screen_number;
1.25 markus 4721:
1.367 djm 4722: if (sc->x11_saved_display == NULL)
4723: sc->x11_saved_display = xstrdup(disp);
4724: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4725: error("x11_request_forwarding_with_spoofing: different "
4726: "$DISPLAY already forwarded");
4727: return;
4728: }
4729:
1.266 djm 4730: cp = strchr(disp, ':');
1.25 markus 4731: if (cp)
4732: cp = strchr(cp, '.');
4733: if (cp)
1.245 deraadt 4734: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4735: else
4736: screen_number = 0;
4737:
1.367 djm 4738: if (sc->x11_saved_proto == NULL) {
1.219 djm 4739: /* Save protocol name. */
1.367 djm 4740: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4741:
4742: /* Extract real authentication data. */
1.367 djm 4743: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4744: for (i = 0; i < data_len; i++) {
4745: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4746: fatal("x11_request_forwarding: bad "
4747: "authentication data: %.100s", data);
1.367 djm 4748: sc->x11_saved_data[i] = value;
1.219 djm 4749: }
1.367 djm 4750: sc->x11_saved_data_len = data_len;
1.353 natano 4751:
4752: /* Generate fake data of the same length. */
1.367 djm 4753: sc->x11_fake_data = xmalloc(data_len);
4754: arc4random_buf(sc->x11_fake_data, data_len);
4755: sc->x11_fake_data_len = data_len;
1.25 markus 4756: }
4757:
4758: /* Convert the fake data into hex. */
1.367 djm 4759: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 4760:
4761: /* Send the request packet. */
1.367 djm 4762: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4763: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4764: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4765: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4766: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4767: (r = sshpkt_send(ssh)) != 0 ||
4768: (r = ssh_packet_write_wait(ssh)) != 0)
4769: fatal("%s: send x11-req: %s", __func__, ssh_err(r));
1.321 djm 4770: free(new_data);
1.1 deraadt 4771: }
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