Annotation of src/usr.bin/ssh/channels.c, Revision 1.376
1.376 ! djm 1: /* $OpenBSD: channels.c,v 1.375 2017/09/24 13:45:34 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"
1.64 markus 76: #include "key.h"
77: #include "authfd.h"
1.147 stevesk 78: #include "pathnames.h"
1.1 deraadt 79:
1.367 djm 80: /* -- agent forwarding */
81: #define NUM_SOCKS 10
1.12 markus 82:
1.367 djm 83: /* -- tcp forwarding */
84: /* special-case port number meaning allow any port */
85: #define FWD_PERMIT_ANY_PORT 0
1.1 deraadt 86:
1.367 djm 87: /* special-case wildcard meaning allow any host */
88: #define FWD_PERMIT_ANY_HOST "*"
1.1 deraadt 89:
1.367 djm 90: /* -- X11 forwarding */
91: /* Maximum number of fake X11 displays to try. */
92: #define MAX_DISPLAYS 1000
1.1 deraadt 93:
1.27 markus 94: /*
95: * Data structure for storing which hosts are permitted for forward requests.
96: * The local sides of any remote forwards are stored in this array to prevent
97: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
98: * network (which might be behind a firewall).
99: */
1.336 millert 100: /* XXX: streamlocal wants a path instead of host:port */
101: /* Overload host_to_connect; we could just make this match Forward */
102: /* XXX - can we use listen_host instead of listen_path? */
1.25 markus 103: typedef struct {
1.41 markus 104: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 105: int port_to_connect; /* Connect to 'port'. */
1.333 markus 106: char *listen_host; /* Remote side should listen address. */
1.336 millert 107: char *listen_path; /* Remote side should listen path. */
108: int listen_port; /* Remote side should listen port. */
1.354 markus 109: Channel *downstream; /* Downstream mux*/
1.1 deraadt 110: } ForwardPermission;
111:
1.367 djm 112: typedef void chan_fn(struct ssh *, Channel *c,
113: fd_set *readset, fd_set *writeset);
1.121 markus 114:
1.367 djm 115: /* Master structure for channels state */
116: struct ssh_channels {
117: /*
118: * Pointer to an array containing all allocated channels. The array
119: * is dynamically extended as needed.
120: */
121: Channel **channels;
1.257 dtucker 122:
1.367 djm 123: /*
124: * Size of the channel array. All slots of the array must always be
125: * initialized (at least the type field); unused slots set to NULL
126: */
127: u_int channels_alloc;
1.257 dtucker 128:
1.367 djm 129: /*
130: * Maximum file descriptor value used in any of the channels. This is
131: * updated in channel_new.
132: */
133: int channel_max_fd;
1.257 dtucker 134:
1.367 djm 135: /*
136: * 'channel_pre*' are called just before select() to add any bits
137: * relevant to channels in the select bitmasks.
138: *
139: * 'channel_post*': perform any appropriate operations for
140: * channels which have events pending.
141: */
142: chan_fn **channel_pre;
143: chan_fn **channel_post;
1.314 dtucker 144:
1.367 djm 145: /* -- tcp forwarding */
1.351 dtucker 146:
1.367 djm 147: /* List of all permitted host/port pairs to connect by the user. */
148: ForwardPermission *permitted_opens;
1.1 deraadt 149:
1.367 djm 150: /* List of all permitted host/port pairs to connect by the admin. */
151: ForwardPermission *permitted_adm_opens;
1.121 markus 152:
1.367 djm 153: /*
154: * Number of permitted host/port pairs in the array permitted by
155: * the user.
156: */
157: u_int num_permitted_opens;
1.121 markus 158:
1.367 djm 159: /*
160: * Number of permitted host/port pair in the array permitted by
161: * the admin.
162: */
163: u_int num_adm_permitted_opens;
1.121 markus 164:
1.367 djm 165: /*
166: * If this is true, all opens are permitted. This is the case on
167: * the server on which we have to trust the client anyway, and the
168: * user could do anything after logging in anyway.
169: */
170: int all_opens_permitted;
1.219 djm 171:
1.367 djm 172: /* -- X11 forwarding */
1.121 markus 173:
1.367 djm 174: /* Saved X11 local (client) display. */
175: char *x11_saved_display;
1.121 markus 176:
1.367 djm 177: /* Saved X11 authentication protocol name. */
178: char *x11_saved_proto;
1.347 djm 179:
1.367 djm 180: /* Saved X11 authentication data. This is the real data. */
181: char *x11_saved_data;
182: u_int x11_saved_data_len;
1.121 markus 183:
1.367 djm 184: /* Deadline after which all X11 connections are refused */
185: u_int x11_refuse_time;
1.121 markus 186:
1.367 djm 187: /*
188: * Fake X11 authentication data. This is what the server will be
189: * sending us; we should replace any occurrences of this by the
190: * real data.
191: */
192: u_char *x11_fake_data;
193: u_int x11_fake_data_len;
1.121 markus 194:
1.367 djm 195: /* AF_UNSPEC or AF_INET or AF_INET6 */
196: int IPv4or6;
197: };
1.1 deraadt 198:
1.121 markus 199: /* helper */
1.367 djm 200: static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
1.354 markus 201: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 202:
1.276 djm 203: /* non-blocking connect helpers */
204: static int connect_next(struct channel_connect *);
205: static void channel_connect_ctx_free(struct channel_connect *);
1.372 markus 206: static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
207: static int rdynamic_connect_finish(struct ssh *, Channel *);
1.276 djm 208:
1.367 djm 209: /* Setup helper */
210: static void channel_handler_init(struct ssh_channels *sc);
211:
1.121 markus 212: /* -- channel core */
1.41 markus 213:
1.367 djm 214: void
215: channel_init_channels(struct ssh *ssh)
216: {
217: struct ssh_channels *sc;
218:
219: if ((sc = calloc(1, sizeof(*sc))) == NULL ||
220: (sc->channel_pre = calloc(SSH_CHANNEL_MAX_TYPE,
221: sizeof(*sc->channel_pre))) == NULL ||
222: (sc->channel_post = calloc(SSH_CHANNEL_MAX_TYPE,
223: sizeof(*sc->channel_post))) == NULL)
224: fatal("%s: allocation failed", __func__);
225: sc->channels_alloc = 10;
226: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
227: sc->IPv4or6 = AF_UNSPEC;
228: channel_handler_init(sc);
229:
230: ssh->chanctxt = sc;
231: }
232:
1.41 markus 233: Channel *
1.367 djm 234: channel_by_id(struct ssh *ssh, int id)
1.41 markus 235: {
236: Channel *c;
1.113 markus 237:
1.367 djm 238: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
239: logit("%s: %d: bad id", __func__, id);
1.41 markus 240: return NULL;
241: }
1.367 djm 242: c = ssh->chanctxt->channels[id];
1.113 markus 243: if (c == NULL) {
1.367 djm 244: logit("%s: %d: bad id: channel free", __func__, id);
1.41 markus 245: return NULL;
246: }
247: return c;
1.55 markus 248: }
249:
1.354 markus 250: Channel *
1.368 djm 251: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 252: {
253: Channel *c;
254: u_int i;
255:
1.367 djm 256: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
257: c = ssh->chanctxt->channels[i];
1.368 djm 258: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 259: return c;
260: }
261: return NULL;
262: }
263:
1.27 markus 264: /*
1.229 markus 265: * Returns the channel if it is allowed to receive protocol messages.
266: * Private channels, like listening sockets, may not receive messages.
267: */
268: Channel *
1.367 djm 269: channel_lookup(struct ssh *ssh, int id)
1.229 markus 270: {
271: Channel *c;
272:
1.367 djm 273: if ((c = channel_by_id(ssh, id)) == NULL)
274: return NULL;
1.229 markus 275:
1.237 deraadt 276: switch (c->type) {
1.229 markus 277: case SSH_CHANNEL_X11_OPEN:
278: case SSH_CHANNEL_LARVAL:
279: case SSH_CHANNEL_CONNECTING:
280: case SSH_CHANNEL_DYNAMIC:
1.372 markus 281: case SSH_CHANNEL_RDYNAMIC_OPEN:
282: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 283: case SSH_CHANNEL_OPENING:
284: case SSH_CHANNEL_OPEN:
1.323 dtucker 285: case SSH_CHANNEL_ABANDONED:
1.354 markus 286: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 287: return c;
1.229 markus 288: }
289: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 290: return NULL;
1.229 markus 291: }
292:
293: /*
1.55 markus 294: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 295: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 296: */
1.127 itojun 297: static void
1.367 djm 298: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 299: int extusage, int nonblock, int is_tty)
1.1 deraadt 300: {
1.367 djm 301: struct ssh_channels *sc = ssh->chanctxt;
302:
1.25 markus 303: /* Update the maximum file descriptor value. */
1.367 djm 304: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, rfd);
305: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, wfd);
306: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, efd);
1.84 markus 307:
1.298 dtucker 308: if (rfd != -1)
309: fcntl(rfd, F_SETFD, FD_CLOEXEC);
310: if (wfd != -1 && wfd != rfd)
311: fcntl(wfd, F_SETFD, FD_CLOEXEC);
312: if (efd != -1 && efd != rfd && efd != wfd)
313: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 314:
1.52 markus 315: c->rfd = rfd;
316: c->wfd = wfd;
317: c->sock = (rfd == wfd) ? rfd : -1;
318: c->efd = efd;
319: c->extended_usage = extusage;
1.71 markus 320:
1.282 dtucker 321: if ((c->isatty = is_tty) != 0)
1.194 markus 322: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 323:
1.71 markus 324: /* enable nonblocking mode */
325: if (nonblock) {
326: if (rfd != -1)
327: set_nonblock(rfd);
328: if (wfd != -1)
329: set_nonblock(wfd);
330: if (efd != -1)
331: set_nonblock(efd);
332: }
1.52 markus 333: }
334:
335: /*
336: * Allocate a new channel object and set its type and socket. This will cause
337: * remote_name to be freed.
338: */
1.113 markus 339: Channel *
1.367 djm 340: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 341: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 342: {
1.367 djm 343: struct ssh_channels *sc = ssh->chanctxt;
344: u_int i, found;
1.52 markus 345: Channel *c;
1.25 markus 346:
347: /* Try to find a free slot where to put the new channel. */
1.367 djm 348: for (i = 0; i < sc->channels_alloc; i++) {
349: if (sc->channels[i] == NULL) {
1.25 markus 350: /* Found a free slot. */
1.367 djm 351: found = i;
1.25 markus 352: break;
353: }
1.367 djm 354: }
355: if (i >= sc->channels_alloc) {
356: /*
357: * There are no free slots. Take last+1 slot and expand
358: * the array.
359: */
360: found = sc->channels_alloc;
361: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
362: fatal("%s: internal error: channels_alloc %d too big",
363: __func__, sc->channels_alloc);
364: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
365: sc->channels_alloc + 10, sizeof(*sc->channels));
366: sc->channels_alloc += 10;
367: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 368: }
1.113 markus 369: /* Initialize and return new channel. */
1.367 djm 370: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
371: if ((c->input = sshbuf_new()) == NULL ||
372: (c->output = sshbuf_new()) == NULL ||
373: (c->extended = sshbuf_new()) == NULL)
374: fatal("%s: sshbuf_new failed", __func__);
1.159 markus 375: c->ostate = CHAN_OUTPUT_OPEN;
376: c->istate = CHAN_INPUT_OPEN;
1.367 djm 377: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 378: c->self = found;
379: c->type = type;
1.41 markus 380: c->ctype = ctype;
1.51 markus 381: c->local_window = window;
382: c->local_window_max = window;
383: c->local_maxpacket = maxpack;
1.190 markus 384: c->remote_name = xstrdup(remote_name);
1.302 djm 385: c->ctl_chan = -1;
1.299 markus 386: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 387: TAILQ_INIT(&c->status_confirms);
1.25 markus 388: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 389: return c;
1.1 deraadt 390: }
1.52 markus 391:
1.367 djm 392: static void
393: channel_find_maxfd(struct ssh_channels *sc)
1.132 markus 394: {
1.209 avsm 395: u_int i;
396: int max = 0;
1.132 markus 397: Channel *c;
398:
1.367 djm 399: for (i = 0; i < sc->channels_alloc; i++) {
400: c = sc->channels[i];
1.132 markus 401: if (c != NULL) {
1.352 deraadt 402: max = MAXIMUM(max, c->rfd);
403: max = MAXIMUM(max, c->wfd);
404: max = MAXIMUM(max, c->efd);
1.132 markus 405: }
406: }
1.367 djm 407: sc->channel_max_fd = max;
1.132 markus 408: }
409:
410: int
1.367 djm 411: channel_close_fd(struct ssh *ssh, int *fdp)
1.132 markus 412: {
1.367 djm 413: struct ssh_channels *sc = ssh->chanctxt;
1.132 markus 414: int ret = 0, fd = *fdp;
415:
416: if (fd != -1) {
417: ret = close(fd);
418: *fdp = -1;
1.367 djm 419: if (fd == sc->channel_max_fd)
420: channel_find_maxfd(sc);
1.132 markus 421: }
422: return ret;
423: }
424:
1.52 markus 425: /* Close all channel fd/socket. */
1.127 itojun 426: static void
1.367 djm 427: channel_close_fds(struct ssh *ssh, Channel *c)
428: {
429: channel_close_fd(ssh, &c->sock);
430: channel_close_fd(ssh, &c->rfd);
431: channel_close_fd(ssh, &c->wfd);
432: channel_close_fd(ssh, &c->efd);
433: }
434:
435: static void
436: fwd_perm_clear(ForwardPermission *fp)
1.52 markus 437: {
1.367 djm 438: free(fp->host_to_connect);
439: free(fp->listen_host);
440: free(fp->listen_path);
441: bzero(fp, sizeof(*fp));
442: }
443:
444: enum { FWDPERM_USER, FWDPERM_ADMIN };
445:
446: static int
447: fwd_perm_list_add(struct ssh *ssh, int which,
448: const char *host_to_connect, int port_to_connect,
449: const char *listen_host, const char *listen_path, int listen_port,
450: Channel *downstream)
451: {
452: ForwardPermission **fpl;
453: u_int n, *nfpl;
454:
455: switch (which) {
456: case FWDPERM_USER:
457: fpl = &ssh->chanctxt->permitted_opens;
458: nfpl = &ssh->chanctxt->num_permitted_opens;
459: break;
460: case FWDPERM_ADMIN:
461: fpl = &ssh->chanctxt->permitted_adm_opens;
462: nfpl = &ssh->chanctxt->num_adm_permitted_opens;
463: break;
464: default:
465: fatal("%s: invalid list %d", __func__, which);
466: }
467:
468: if (*nfpl >= INT_MAX)
469: fatal("%s: overflow", __func__);
470:
471: *fpl = xrecallocarray(*fpl, *nfpl, *nfpl + 1, sizeof(**fpl));
472: n = (*nfpl)++;
473: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
474: (*fpl)[n].host_to_connect = MAYBE_DUP(host_to_connect);
475: (*fpl)[n].port_to_connect = port_to_connect;
476: (*fpl)[n].listen_host = MAYBE_DUP(listen_host);
477: (*fpl)[n].listen_path = MAYBE_DUP(listen_path);
478: (*fpl)[n].listen_port = listen_port;
479: (*fpl)[n].downstream = downstream;
480: #undef MAYBE_DUP
481: return (int)n;
482: }
483:
484: static void
485: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
486: {
487: struct ssh_channels *sc = ssh->chanctxt;
488: ForwardPermission *fp;
489: int r;
490: u_int i;
491:
492: for (i = 0; i < sc->num_permitted_opens; i++) {
493: fp = &sc->permitted_opens[i];
494: if (fp->downstream != c)
495: continue;
496:
497: /* cancel on the server, since mux client is gone */
498: debug("channel %d: cleanup remote forward for %s:%u",
499: c->self, fp->listen_host, fp->listen_port);
500: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
501: (r = sshpkt_put_cstring(ssh,
502: "cancel-tcpip-forward")) != 0 ||
503: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
504: (r = sshpkt_put_cstring(ssh,
505: channel_rfwd_bind_host(fp->listen_host))) != 0 ||
506: (r = sshpkt_put_u32(ssh, fp->listen_port)) != 0 ||
507: (r = sshpkt_send(ssh)) != 0) {
508: fatal("%s: channel %i: %s", __func__,
509: c->self, ssh_err(r));
510: }
511: fwd_perm_clear(fp); /* unregister */
512: }
1.121 markus 513: }
514:
515: /* Free the channel and close its fd/socket. */
516: void
1.367 djm 517: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 518: {
1.367 djm 519: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 520: char *s;
1.209 avsm 521: u_int i, n;
1.354 markus 522: Channel *other;
1.275 djm 523: struct channel_confirm *cc;
1.121 markus 524:
1.367 djm 525: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
526: if ((other = sc->channels[i]) == NULL)
527: continue;
528: n++;
529: /* detach from mux client and prepare for closing */
530: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
531: other->type == SSH_CHANNEL_MUX_PROXY &&
532: other->mux_ctx == c) {
533: other->mux_ctx = NULL;
534: other->type = SSH_CHANNEL_OPEN;
535: other->istate = CHAN_INPUT_CLOSED;
536: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 537: }
538: }
1.209 avsm 539: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 540: c->remote_name ? c->remote_name : "???", n);
541:
1.367 djm 542: if (c->type == SSH_CHANNEL_MUX_CLIENT)
543: mux_remove_remote_forwardings(ssh, c);
1.354 markus 544:
1.367 djm 545: s = channel_open_message(ssh);
1.194 markus 546: debug3("channel %d: status: %s", c->self, s);
1.321 djm 547: free(s);
1.121 markus 548:
1.367 djm 549: channel_close_fds(ssh, c);
550: sshbuf_free(c->input);
551: sshbuf_free(c->output);
552: sshbuf_free(c->extended);
553: c->input = c->output = c->extended = NULL;
1.321 djm 554: free(c->remote_name);
555: c->remote_name = NULL;
556: free(c->path);
557: c->path = NULL;
558: free(c->listening_addr);
559: c->listening_addr = NULL;
1.275 djm 560: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
561: if (cc->abandon_cb != NULL)
1.367 djm 562: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 563: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 564: explicit_bzero(cc, sizeof(*cc));
1.321 djm 565: free(cc);
1.275 djm 566: }
1.280 djm 567: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 568: c->filter_cleanup(ssh, c->self, c->filter_ctx);
569: sc->channels[c->self] = NULL;
1.371 millert 570: explicit_bzero(c, sizeof(*c));
1.321 djm 571: free(c);
1.121 markus 572: }
573:
574: void
1.367 djm 575: channel_free_all(struct ssh *ssh)
1.121 markus 576: {
1.209 avsm 577: u_int i;
1.121 markus 578:
1.367 djm 579: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
580: if (ssh->chanctxt->channels[i] != NULL)
581: channel_free(ssh, ssh->chanctxt->channels[i]);
1.131 markus 582: }
583:
1.121 markus 584: /*
585: * Closes the sockets/fds of all channels. This is used to close extra file
586: * descriptors after a fork.
587: */
588: void
1.367 djm 589: channel_close_all(struct ssh *ssh)
1.121 markus 590: {
1.209 avsm 591: u_int i;
1.121 markus 592:
1.367 djm 593: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
594: if (ssh->chanctxt->channels[i] != NULL)
595: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 596: }
597:
598: /*
1.131 markus 599: * Stop listening to channels.
600: */
601: void
1.367 djm 602: channel_stop_listening(struct ssh *ssh)
1.131 markus 603: {
1.209 avsm 604: u_int i;
1.131 markus 605: Channel *c;
606:
1.367 djm 607: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
608: c = ssh->chanctxt->channels[i];
1.131 markus 609: if (c != NULL) {
610: switch (c->type) {
611: case SSH_CHANNEL_AUTH_SOCKET:
612: case SSH_CHANNEL_PORT_LISTENER:
613: case SSH_CHANNEL_RPORT_LISTENER:
614: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 615: case SSH_CHANNEL_UNIX_LISTENER:
616: case SSH_CHANNEL_RUNIX_LISTENER:
1.367 djm 617: channel_close_fd(ssh, &c->sock);
618: channel_free(ssh, c);
1.131 markus 619: break;
620: }
621: }
622: }
623: }
624:
625: /*
1.121 markus 626: * Returns true if no channel has too much buffered data, and false if one or
627: * more channel is overfull.
628: */
629: int
1.367 djm 630: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 631: {
632: u_int i;
1.367 djm 633: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 634: Channel *c;
635:
1.367 djm 636: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
637: c = ssh->chanctxt->channels[i];
638: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
639: continue;
640: if (sshbuf_len(c->output) > maxsize) {
641: debug2("channel %d: big output buffer %zu > %u",
642: c->self, sshbuf_len(c->output), maxsize);
643: return 0;
1.121 markus 644: }
645: }
646: return 1;
647: }
648:
649: /* Returns true if any channel is still open. */
650: int
1.367 djm 651: channel_still_open(struct ssh *ssh)
1.121 markus 652: {
1.209 avsm 653: u_int i;
1.121 markus 654: Channel *c;
655:
1.367 djm 656: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
657: c = ssh->chanctxt->channels[i];
1.121 markus 658: if (c == NULL)
659: continue;
660: switch (c->type) {
661: case SSH_CHANNEL_X11_LISTENER:
662: case SSH_CHANNEL_PORT_LISTENER:
663: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 664: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 665: case SSH_CHANNEL_CLOSED:
666: case SSH_CHANNEL_AUTH_SOCKET:
667: case SSH_CHANNEL_DYNAMIC:
1.372 markus 668: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 669: case SSH_CHANNEL_CONNECTING:
670: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 671: case SSH_CHANNEL_ABANDONED:
1.336 millert 672: case SSH_CHANNEL_UNIX_LISTENER:
673: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 674: continue;
675: case SSH_CHANNEL_LARVAL:
676: continue;
677: case SSH_CHANNEL_OPENING:
678: case SSH_CHANNEL_OPEN:
1.372 markus 679: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 680: case SSH_CHANNEL_X11_OPEN:
1.302 djm 681: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 682: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 683: return 1;
684: default:
1.358 djm 685: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 686: /* NOTREACHED */
687: }
688: }
689: return 0;
690: }
691:
692: /* Returns the id of an open channel suitable for keepaliving */
693: int
1.367 djm 694: channel_find_open(struct ssh *ssh)
1.121 markus 695: {
1.209 avsm 696: u_int i;
1.121 markus 697: Channel *c;
698:
1.367 djm 699: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
700: c = ssh->chanctxt->channels[i];
1.368 djm 701: if (c == NULL || !c->have_remote_id)
1.121 markus 702: continue;
703: switch (c->type) {
704: case SSH_CHANNEL_CLOSED:
705: case SSH_CHANNEL_DYNAMIC:
1.372 markus 706: case SSH_CHANNEL_RDYNAMIC_OPEN:
707: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 708: case SSH_CHANNEL_X11_LISTENER:
709: case SSH_CHANNEL_PORT_LISTENER:
710: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 711: case SSH_CHANNEL_MUX_LISTENER:
712: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 713: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 714: case SSH_CHANNEL_OPENING:
715: case SSH_CHANNEL_CONNECTING:
716: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 717: case SSH_CHANNEL_ABANDONED:
1.336 millert 718: case SSH_CHANNEL_UNIX_LISTENER:
719: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 720: continue;
721: case SSH_CHANNEL_LARVAL:
722: case SSH_CHANNEL_AUTH_SOCKET:
723: case SSH_CHANNEL_OPEN:
724: case SSH_CHANNEL_X11_OPEN:
725: return i;
726: default:
1.358 djm 727: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 728: /* NOTREACHED */
729: }
730: }
731: return -1;
732: }
733:
734: /*
735: * Returns a message describing the currently open forwarded connections,
736: * suitable for sending to the client. The message contains crlf pairs for
737: * newlines.
738: */
739: char *
1.367 djm 740: channel_open_message(struct ssh *ssh)
1.121 markus 741: {
1.367 djm 742: struct sshbuf *buf;
1.121 markus 743: Channel *c;
1.209 avsm 744: u_int i;
1.367 djm 745: int r;
746: char *ret;
1.121 markus 747:
1.367 djm 748: if ((buf = sshbuf_new()) == NULL)
749: fatal("%s: sshbuf_new", __func__);
750: if ((r = sshbuf_putf(buf,
751: "The following connections are open:\r\n")) != 0)
752: fatal("%s: sshbuf_putf: %s", __func__, ssh_err(r));
753: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
754: c = ssh->chanctxt->channels[i];
1.121 markus 755: if (c == NULL)
756: continue;
757: switch (c->type) {
758: case SSH_CHANNEL_X11_LISTENER:
759: case SSH_CHANNEL_PORT_LISTENER:
760: case SSH_CHANNEL_RPORT_LISTENER:
761: case SSH_CHANNEL_CLOSED:
762: case SSH_CHANNEL_AUTH_SOCKET:
763: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 764: case SSH_CHANNEL_ABANDONED:
1.302 djm 765: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 766: case SSH_CHANNEL_UNIX_LISTENER:
767: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 768: continue;
769: case SSH_CHANNEL_LARVAL:
770: case SSH_CHANNEL_OPENING:
771: case SSH_CHANNEL_CONNECTING:
772: case SSH_CHANNEL_DYNAMIC:
1.372 markus 773: case SSH_CHANNEL_RDYNAMIC_OPEN:
774: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 775: case SSH_CHANNEL_OPEN:
776: case SSH_CHANNEL_X11_OPEN:
1.354 markus 777: case SSH_CHANNEL_MUX_PROXY:
778: case SSH_CHANNEL_MUX_CLIENT:
1.367 djm 779: if ((r = sshbuf_putf(buf, " #%d %.300s "
1.368 djm 780: "(t%d %s%u i%u/%zu o%u/%zu fd %d/%d cc %d)\r\n",
1.121 markus 781: c->self, c->remote_name,
1.368 djm 782: c->type,
783: c->have_remote_id ? "r" : "nr", c->remote_id,
1.367 djm 784: c->istate, sshbuf_len(c->input),
785: c->ostate, sshbuf_len(c->output),
786: c->rfd, c->wfd, c->ctl_chan)) != 0)
787: fatal("%s: sshbuf_putf: %s",
788: __func__, ssh_err(r));
1.121 markus 789: continue;
790: default:
1.367 djm 791: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 792: /* NOTREACHED */
793: }
794: }
1.367 djm 795: if ((ret = sshbuf_dup_string(buf)) == NULL)
796: fatal("%s: sshbuf_dup_string", __func__);
797: sshbuf_free(buf);
798: return ret;
799: }
800:
801: static void
802: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
803: {
804: int r;
805:
806: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
807: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
808: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
809: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
810: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
811: fatal("%s: channel %i: open: %s", where, c->self, ssh_err(r));
812: }
1.121 markus 813: }
814:
815: void
1.367 djm 816: channel_send_open(struct ssh *ssh, int id)
1.121 markus 817: {
1.367 djm 818: Channel *c = channel_lookup(ssh, id);
819: int r;
1.180 deraadt 820:
1.121 markus 821: if (c == NULL) {
1.188 itojun 822: logit("channel_send_open: %d: bad id", id);
1.121 markus 823: return;
824: }
1.184 markus 825: debug2("channel %d: send open", id);
1.367 djm 826: open_preamble(ssh, __func__, c, c->ctype);
827: if ((r = sshpkt_send(ssh)) != 0)
828: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.121 markus 829: }
830:
831: void
1.367 djm 832: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 833: {
1.367 djm 834: Channel *c = channel_lookup(ssh, id);
835: int r;
1.180 deraadt 836:
1.121 markus 837: if (c == NULL) {
1.367 djm 838: logit("%s: %d: unknown channel id", __func__, id);
1.121 markus 839: return;
840: }
1.368 djm 841: if (!c->have_remote_id)
842: fatal(":%s: channel %d: no remote id", __func__, c->self);
843:
1.204 djm 844: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 845: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
846: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
847: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
848: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
849: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
850: }
1.121 markus 851: }
1.241 deraadt 852:
1.121 markus 853: void
1.367 djm 854: channel_register_status_confirm(struct ssh *ssh, int id,
855: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 856: {
857: struct channel_confirm *cc;
858: Channel *c;
859:
1.367 djm 860: if ((c = channel_lookup(ssh, id)) == NULL)
861: fatal("%s: %d: bad id", __func__, id);
1.275 djm 862:
1.327 djm 863: cc = xcalloc(1, sizeof(*cc));
1.275 djm 864: cc->cb = cb;
865: cc->abandon_cb = abandon_cb;
866: cc->ctx = ctx;
867: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
868: }
869:
870: void
1.367 djm 871: channel_register_open_confirm(struct ssh *ssh, int id,
872: channel_open_fn *fn, void *ctx)
1.121 markus 873: {
1.367 djm 874: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 875:
1.121 markus 876: if (c == NULL) {
1.367 djm 877: logit("%s: %d: bad id", __func__, id);
1.121 markus 878: return;
879: }
1.275 djm 880: c->open_confirm = fn;
881: c->open_confirm_ctx = ctx;
1.121 markus 882: }
1.241 deraadt 883:
1.121 markus 884: void
1.367 djm 885: channel_register_cleanup(struct ssh *ssh, int id,
886: channel_callback_fn *fn, int do_close)
1.121 markus 887: {
1.367 djm 888: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 889:
1.121 markus 890: if (c == NULL) {
1.367 djm 891: logit("%s: %d: bad id", __func__, id);
1.121 markus 892: return;
893: }
1.131 markus 894: c->detach_user = fn;
1.225 djm 895: c->detach_close = do_close;
1.121 markus 896: }
1.241 deraadt 897:
1.121 markus 898: void
1.367 djm 899: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 900: {
1.367 djm 901: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 902:
1.121 markus 903: if (c == NULL) {
1.367 djm 904: logit("%s: %d: bad id", __func__, id);
1.121 markus 905: return;
1.52 markus 906: }
1.131 markus 907: c->detach_user = NULL;
1.225 djm 908: c->detach_close = 0;
1.121 markus 909: }
1.241 deraadt 910:
1.121 markus 911: void
1.367 djm 912: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 913: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 914: {
1.367 djm 915: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 916:
1.121 markus 917: if (c == NULL) {
1.367 djm 918: logit("%s: %d: bad id", __func__, id);
1.121 markus 919: return;
1.52 markus 920: }
1.231 reyk 921: c->input_filter = ifn;
922: c->output_filter = ofn;
1.279 djm 923: c->filter_ctx = ctx;
1.280 djm 924: c->filter_cleanup = cfn;
1.52 markus 925: }
926:
1.49 markus 927: void
1.367 djm 928: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 929: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 930: {
1.367 djm 931: Channel *c = channel_lookup(ssh, id);
932: int r;
1.180 deraadt 933:
1.121 markus 934: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
935: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 936: if (!c->have_remote_id)
937: fatal(":%s: channel %d: no remote id", __func__, c->self);
938:
1.367 djm 939: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 940: c->type = SSH_CHANNEL_OPEN;
1.168 markus 941: c->local_window = c->local_window_max = window_max;
1.367 djm 942:
943: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
944: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
945: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
946: (r = sshpkt_send(ssh)) != 0)
947: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.1 deraadt 948: }
949:
1.127 itojun 950: static void
1.367 djm 951: channel_pre_listener(struct ssh *ssh, Channel *c,
952: fd_set *readset, fd_set *writeset)
1.41 markus 953: {
954: FD_SET(c->sock, readset);
955: }
956:
1.127 itojun 957: static void
1.367 djm 958: channel_pre_connecting(struct ssh *ssh, Channel *c,
959: fd_set *readset, fd_set *writeset)
1.75 markus 960: {
961: debug3("channel %d: waiting for connection", c->self);
962: FD_SET(c->sock, writeset);
963: }
964:
1.127 itojun 965: static void
1.367 djm 966: channel_pre_open(struct ssh *ssh, Channel *c,
967: fd_set *readset, fd_set *writeset)
1.41 markus 968: {
1.44 markus 969: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 970: c->remote_window > 0 &&
1.367 djm 971: sshbuf_len(c->input) < c->remote_window &&
972: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.44 markus 973: FD_SET(c->rfd, readset);
974: if (c->ostate == CHAN_OUTPUT_OPEN ||
975: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 976: if (sshbuf_len(c->output) > 0) {
1.44 markus 977: FD_SET(c->wfd, writeset);
978: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 979: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 980: debug2("channel %d: "
981: "obuf_empty delayed efd %d/(%zu)", c->self,
982: c->efd, sshbuf_len(c->extended));
1.172 markus 983: else
1.367 djm 984: chan_obuf_empty(ssh, c);
1.44 markus 985: }
986: }
987: /** XXX check close conditions, too */
1.358 djm 988: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
989: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 990: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 991: sshbuf_len(c->extended) > 0)
1.44 markus 992: FD_SET(c->efd, writeset);
1.306 djm 993: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
994: (c->extended_usage == CHAN_EXTENDED_READ ||
995: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 996: sshbuf_len(c->extended) < c->remote_window)
1.44 markus 997: FD_SET(c->efd, readset);
998: }
1.204 djm 999: /* XXX: What about efd? races? */
1.44 markus 1000: }
1001:
1.41 markus 1002: /*
1003: * This is a special state for X11 authentication spoofing. An opened X11
1004: * connection (when authentication spoofing is being done) remains in this
1005: * state until the first packet has been completely read. The authentication
1006: * data in that packet is then substituted by the real data if it matches the
1007: * fake data, and the channel is put into normal mode.
1.51 markus 1008: * XXX All this happens at the client side.
1.121 markus 1009: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1010: */
1.127 itojun 1011: static int
1.367 djm 1012: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1013: {
1.367 djm 1014: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1015: u_char *ucp;
1016: u_int proto_len, data_len;
1.25 markus 1017:
1.347 djm 1018: /* Is this being called after the refusal deadline? */
1.367 djm 1019: if (sc->x11_refuse_time != 0 &&
1020: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1021: verbose("Rejected X11 connection after ForwardX11Timeout "
1022: "expired");
1023: return -1;
1024: }
1025:
1.41 markus 1026: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1027: if (sshbuf_len(b) < 12)
1.41 markus 1028: return 0;
1029:
1030: /* Parse the lengths of variable-length fields. */
1.367 djm 1031: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1032: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1033: proto_len = 256 * ucp[6] + ucp[7];
1034: data_len = 256 * ucp[8] + ucp[9];
1035: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1036: proto_len = ucp[6] + 256 * ucp[7];
1037: data_len = ucp[8] + 256 * ucp[9];
1038: } else {
1.194 markus 1039: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1040: ucp[0]);
1.41 markus 1041: return -1;
1042: }
1043:
1044: /* Check if the whole packet is in buffer. */
1.367 djm 1045: if (sshbuf_len(b) <
1.41 markus 1046: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1047: return 0;
1048:
1049: /* Check if authentication protocol matches. */
1.367 djm 1050: if (proto_len != strlen(sc->x11_saved_proto) ||
1051: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1052: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1053: return -1;
1054: }
1055: /* Check if authentication data matches our fake data. */
1.367 djm 1056: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1057: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1058: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1059: debug2("X11 auth data does not match fake data.");
1.41 markus 1060: return -1;
1061: }
1062: /* Check fake data length */
1.367 djm 1063: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1064: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1065: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1066: return -1;
1067: }
1068: /*
1069: * Received authentication protocol and data match
1070: * our fake data. Substitute the fake data with real
1071: * data.
1072: */
1073: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1074: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1075: return 1;
1076: }
1077:
1.127 itojun 1078: static void
1.367 djm 1079: channel_pre_x11_open(struct ssh *ssh, Channel *c,
1080: fd_set *readset, fd_set *writeset)
1.41 markus 1081: {
1.367 djm 1082: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1083:
1084: /* c->force_drain = 1; */
1085:
1.41 markus 1086: if (ret == 1) {
1087: c->type = SSH_CHANNEL_OPEN;
1.367 djm 1088: channel_pre_open(ssh, c, readset, writeset);
1.41 markus 1089: } else if (ret == -1) {
1.188 itojun 1090: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1091: debug2("X11 rejected %d i%d/o%d",
1092: c->self, c->istate, c->ostate);
1093: chan_read_failed(ssh, c);
1094: sshbuf_reset(c->input);
1095: chan_ibuf_empty(ssh, c);
1096: sshbuf_reset(c->output);
1097: chan_write_failed(ssh, c);
1.194 markus 1098: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1099: }
1100: }
1.25 markus 1101:
1.302 djm 1102: static void
1.367 djm 1103: channel_pre_mux_client(struct ssh *ssh,
1104: Channel *c, fd_set *readset, fd_set *writeset)
1.302 djm 1105: {
1.304 djm 1106: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1107: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.302 djm 1108: FD_SET(c->rfd, readset);
1109: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1110: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1111: sshbuf_reset(c->input);
1112: chan_ibuf_empty(ssh, c);
1.302 djm 1113: /* Start output drain. XXX just kill chan? */
1.367 djm 1114: chan_rcvd_oclose(ssh, c);
1.302 djm 1115: }
1116: if (c->ostate == CHAN_OUTPUT_OPEN ||
1117: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1118: if (sshbuf_len(c->output) > 0)
1.302 djm 1119: FD_SET(c->wfd, writeset);
1120: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1121: chan_obuf_empty(ssh, c);
1.302 djm 1122: }
1123: }
1124:
1.104 markus 1125: /* try to decode a socks4 header */
1.127 itojun 1126: static int
1.372 markus 1127: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1128: {
1.367 djm 1129: const u_char *p;
1130: char *host;
1.292 djm 1131: u_int len, have, i, found, need;
1.148 deraadt 1132: char username[256];
1.103 markus 1133: struct {
1134: u_int8_t version;
1135: u_int8_t command;
1136: u_int16_t dest_port;
1.104 markus 1137: struct in_addr dest_addr;
1.103 markus 1138: } s4_req, s4_rsp;
1.367 djm 1139: int r;
1.103 markus 1140:
1.104 markus 1141: debug2("channel %d: decode socks4", c->self);
1.109 markus 1142:
1.372 markus 1143: have = sshbuf_len(input);
1.109 markus 1144: len = sizeof(s4_req);
1145: if (have < len)
1146: return 0;
1.372 markus 1147: p = sshbuf_ptr(input);
1.292 djm 1148:
1149: need = 1;
1150: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1151: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1152: debug2("channel %d: socks4a request", c->self);
1153: /* ... and needs an extra string (the hostname) */
1154: need = 2;
1155: }
1156: /* Check for terminating NUL on the string(s) */
1.109 markus 1157: for (found = 0, i = len; i < have; i++) {
1158: if (p[i] == '\0') {
1.292 djm 1159: found++;
1160: if (found == need)
1161: break;
1.109 markus 1162: }
1163: if (i > 1024) {
1164: /* the peer is probably sending garbage */
1165: debug("channel %d: decode socks4: too long",
1166: c->self);
1167: return -1;
1168: }
1169: }
1.292 djm 1170: if (found < need)
1.109 markus 1171: return 0;
1.372 markus 1172: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1173: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1174: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1175: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.367 djm 1176: debug("channels %d: decode socks4: %s", c->self, ssh_err(r));
1177: return -1;
1178: }
1.372 markus 1179: have = sshbuf_len(input);
1180: p = sshbuf_ptr(input);
1.364 djm 1181: if (memchr(p, '\0', have) == NULL) {
1182: error("channel %d: decode socks4: user not nul terminated",
1.331 djm 1183: c->self);
1.364 djm 1184: return -1;
1185: }
1.103 markus 1186: len = strlen(p);
1.106 markus 1187: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1188: len++; /* trailing '\0' */
1.103 markus 1189: strlcpy(username, p, sizeof(username));
1.372 markus 1190: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1191: fatal("%s: channel %d: consume: %s", __func__,
1192: c->self, ssh_err(r));
1193: }
1.321 djm 1194: free(c->path);
1195: c->path = NULL;
1.292 djm 1196: if (need == 1) { /* SOCKS4: one string */
1197: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1198: c->path = xstrdup(host);
1.292 djm 1199: } else { /* SOCKS4A: two strings */
1.372 markus 1200: have = sshbuf_len(input);
1201: p = sshbuf_ptr(input);
1.364 djm 1202: if (memchr(p, '\0', have) == NULL) {
1203: error("channel %d: decode socks4a: host not nul "
1204: "terminated", c->self);
1205: return -1;
1206: }
1.292 djm 1207: len = strlen(p);
1208: debug2("channel %d: decode socks4a: host %s/%d",
1209: c->self, p, len);
1210: len++; /* trailing '\0' */
1.293 djm 1211: if (len > NI_MAXHOST) {
1.292 djm 1212: error("channel %d: hostname \"%.100s\" too long",
1213: c->self, p);
1214: return -1;
1215: }
1.293 djm 1216: c->path = xstrdup(p);
1.372 markus 1217: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1218: fatal("%s: channel %d: consume: %s", __func__,
1219: c->self, ssh_err(r));
1220: }
1.292 djm 1221: }
1.103 markus 1222: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1223:
1.194 markus 1224: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1225: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1226:
1.104 markus 1227: if (s4_req.command != 1) {
1.292 djm 1228: debug("channel %d: cannot handle: %s cn %d",
1229: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1230: return -1;
1.103 markus 1231: }
1.104 markus 1232: s4_rsp.version = 0; /* vn: 0 for reply */
1233: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1234: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1235: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.372 markus 1236: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0) {
1.367 djm 1237: fatal("%s: channel %d: append reply: %s", __func__,
1238: c->self, ssh_err(r));
1239: }
1.104 markus 1240: return 1;
1241: }
1242:
1.193 markus 1243: /* try to decode a socks5 header */
1244: #define SSH_SOCKS5_AUTHDONE 0x1000
1245: #define SSH_SOCKS5_NOAUTH 0x00
1246: #define SSH_SOCKS5_IPV4 0x01
1247: #define SSH_SOCKS5_DOMAIN 0x03
1248: #define SSH_SOCKS5_IPV6 0x04
1249: #define SSH_SOCKS5_CONNECT 0x01
1250: #define SSH_SOCKS5_SUCCESS 0x00
1251:
1252: static int
1.372 markus 1253: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1254: {
1.367 djm 1255: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1256: struct {
1257: u_int8_t version;
1258: u_int8_t command;
1259: u_int8_t reserved;
1260: u_int8_t atyp;
1261: } s5_req, s5_rsp;
1262: u_int16_t dest_port;
1.324 djm 1263: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1264: const u_char *p;
1.252 djm 1265: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1266: int r;
1.193 markus 1267:
1268: debug2("channel %d: decode socks5", c->self);
1.372 markus 1269: p = sshbuf_ptr(input);
1.193 markus 1270: if (p[0] != 0x05)
1271: return -1;
1.372 markus 1272: have = sshbuf_len(input);
1.193 markus 1273: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1274: /* format: ver | nmethods | methods */
1.198 djm 1275: if (have < 2)
1.193 markus 1276: return 0;
1277: nmethods = p[1];
1278: if (have < nmethods + 2)
1279: return 0;
1280: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1281: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1282: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1283: found = 1;
1284: break;
1285: }
1286: }
1287: if (!found) {
1288: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1289: c->self);
1290: return -1;
1291: }
1.372 markus 1292: if ((r = sshbuf_consume(input, nmethods + 2)) != 0) {
1.367 djm 1293: fatal("%s: channel %d: consume: %s", __func__,
1294: c->self, ssh_err(r));
1295: }
1296: /* version, method */
1.372 markus 1297: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1298: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0) {
1.367 djm 1299: fatal("%s: channel %d: append reply: %s", __func__,
1300: c->self, ssh_err(r));
1301: }
1.193 markus 1302: c->flags |= SSH_SOCKS5_AUTHDONE;
1303: debug2("channel %d: socks5 auth done", c->self);
1304: return 0; /* need more */
1305: }
1306: debug2("channel %d: socks5 post auth", c->self);
1307: if (have < sizeof(s5_req)+1)
1308: return 0; /* need more */
1.247 deraadt 1309: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1310: if (s5_req.version != 0x05 ||
1311: s5_req.command != SSH_SOCKS5_CONNECT ||
1312: s5_req.reserved != 0x00) {
1.194 markus 1313: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1314: return -1;
1315: }
1.213 deraadt 1316: switch (s5_req.atyp){
1.193 markus 1317: case SSH_SOCKS5_IPV4:
1318: addrlen = 4;
1319: af = AF_INET;
1320: break;
1321: case SSH_SOCKS5_DOMAIN:
1322: addrlen = p[sizeof(s5_req)];
1323: af = -1;
1324: break;
1325: case SSH_SOCKS5_IPV6:
1326: addrlen = 16;
1327: af = AF_INET6;
1328: break;
1329: default:
1.194 markus 1330: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1331: return -1;
1332: }
1.252 djm 1333: need = sizeof(s5_req) + addrlen + 2;
1334: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1335: need++;
1336: if (have < need)
1.193 markus 1337: return 0;
1.372 markus 1338: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0) {
1.367 djm 1339: fatal("%s: channel %d: consume: %s", __func__,
1340: c->self, ssh_err(r));
1341: }
1342: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1343: /* host string length */
1.372 markus 1344: if ((r = sshbuf_consume(input, 1)) != 0) {
1.367 djm 1345: fatal("%s: channel %d: consume: %s", __func__,
1346: c->self, ssh_err(r));
1347: }
1348: }
1.372 markus 1349: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1350: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.367 djm 1351: debug("channel %d: parse addr/port: %s", c->self, ssh_err(r));
1352: return -1;
1353: }
1.193 markus 1354: dest_addr[addrlen] = '\0';
1.321 djm 1355: free(c->path);
1356: c->path = NULL;
1.293 djm 1357: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1358: if (addrlen >= NI_MAXHOST) {
1.293 djm 1359: error("channel %d: dynamic request: socks5 hostname "
1360: "\"%.100s\" too long", c->self, dest_addr);
1361: return -1;
1362: }
1363: c->path = xstrdup(dest_addr);
1364: } else {
1365: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1366: return -1;
1367: c->path = xstrdup(ntop);
1368: }
1.193 markus 1369: c->host_port = ntohs(dest_port);
1.198 djm 1370:
1.194 markus 1371: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1372: c->self, c->path, c->host_port, s5_req.command);
1373:
1374: s5_rsp.version = 0x05;
1375: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1376: s5_rsp.reserved = 0; /* ignored */
1377: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1378: dest_port = 0; /* ignored */
1379:
1.372 markus 1380: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1381: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1382: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.367 djm 1383: fatal("%s: channel %d: append reply: %s", __func__,
1384: c->self, ssh_err(r));
1.193 markus 1385: return 1;
1.301 dtucker 1386: }
1387:
1388: Channel *
1.367 djm 1389: channel_connect_stdio_fwd(struct ssh *ssh,
1390: const char *host_to_connect, u_short port_to_connect, int in, int out)
1.301 dtucker 1391: {
1392: Channel *c;
1393:
1.367 djm 1394: debug("%s %s:%d", __func__, host_to_connect, port_to_connect);
1.301 dtucker 1395:
1.367 djm 1396: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1397: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1398: 0, "stdio-forward", /*nonblock*/0);
1399:
1400: c->path = xstrdup(host_to_connect);
1401: c->host_port = port_to_connect;
1402: c->listening_port = 0;
1403: c->force_drain = 1;
1404:
1.367 djm 1405: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1406: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1407:
1408: return c;
1.193 markus 1409: }
1410:
1.104 markus 1411: /* dynamic port forwarding */
1.127 itojun 1412: static void
1.367 djm 1413: channel_pre_dynamic(struct ssh *ssh, Channel *c,
1414: fd_set *readset, fd_set *writeset)
1.104 markus 1415: {
1.367 djm 1416: const u_char *p;
1.217 djm 1417: u_int have;
1418: int ret;
1.103 markus 1419:
1.367 djm 1420: have = sshbuf_len(c->input);
1.104 markus 1421: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1422: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1423: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1424: if (have < 3) {
1.104 markus 1425: /* need more */
1426: FD_SET(c->sock, readset);
1427: return;
1428: }
1429: /* try to guess the protocol */
1.367 djm 1430: p = sshbuf_ptr(c->input);
1431: /* XXX sshbuf_peek_u8? */
1.104 markus 1432: switch (p[0]) {
1433: case 0x04:
1.372 markus 1434: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1435: break;
1436: case 0x05:
1.372 markus 1437: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1438: break;
1439: default:
1440: ret = -1;
1441: break;
1442: }
1443: if (ret < 0) {
1.367 djm 1444: chan_mark_dead(ssh, c);
1.104 markus 1445: } else if (ret == 0) {
1446: debug2("channel %d: pre_dynamic: need more", c->self);
1447: /* need more */
1448: FD_SET(c->sock, readset);
1.372 markus 1449: if (sshbuf_len(c->output))
1450: FD_SET(c->sock, writeset);
1.104 markus 1451: } else {
1452: /* switch to the next state */
1453: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1454: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1455: }
1.103 markus 1456: }
1457:
1.372 markus 1458: /* simulate read-error */
1459: static void
1460: rdynamic_close(struct ssh *ssh, Channel *c)
1461: {
1462: c->type = SSH_CHANNEL_OPEN;
1463: chan_read_failed(ssh, c);
1464: sshbuf_reset(c->input);
1465: chan_ibuf_empty(ssh, c);
1466: sshbuf_reset(c->output);
1467: chan_write_failed(ssh, c);
1468: }
1469:
1470: /* reverse dynamic port forwarding */
1471: static void
1472: channel_before_prepare_select_rdynamic(struct ssh *ssh, Channel *c)
1473: {
1474: const u_char *p;
1475: u_int have, len;
1476: int r, ret;
1477:
1478: have = sshbuf_len(c->output);
1479: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1480: /* sshbuf_dump(c->output, stderr); */
1481: /* EOF received */
1482: if (c->flags & CHAN_EOF_RCVD) {
1483: if ((r = sshbuf_consume(c->output, have)) != 0) {
1484: fatal("%s: channel %d: consume: %s",
1485: __func__, c->self, ssh_err(r));
1486: }
1487: rdynamic_close(ssh, c);
1488: return;
1489: }
1490: /* check if the fixed size part of the packet is in buffer. */
1491: if (have < 3)
1492: return;
1493: /* try to guess the protocol */
1494: p = sshbuf_ptr(c->output);
1495: switch (p[0]) {
1496: case 0x04:
1497: /* switch input/output for reverse forwarding */
1498: ret = channel_decode_socks4(c, c->output, c->input);
1499: break;
1500: case 0x05:
1501: ret = channel_decode_socks5(c, c->output, c->input);
1502: break;
1503: default:
1504: ret = -1;
1505: break;
1506: }
1507: if (ret < 0) {
1508: rdynamic_close(ssh, c);
1509: } else if (ret == 0) {
1510: debug2("channel %d: pre_rdynamic: need more", c->self);
1511: /* send socks request to peer */
1512: len = sshbuf_len(c->input);
1513: if (len > 0 && len < c->remote_window) {
1514: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1515: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1516: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1517: (r = sshpkt_send(ssh)) != 0) {
1518: fatal("%s: channel %i: rdynamic: %s", __func__,
1519: c->self, ssh_err(r));
1520: }
1521: if ((r = sshbuf_consume(c->input, len)) != 0) {
1522: fatal("%s: channel %d: consume: %s",
1523: __func__, c->self, ssh_err(r));
1524: }
1525: c->remote_window -= len;
1526: }
1527: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1528: /* the connect failed */
1529: rdynamic_close(ssh, c);
1530: }
1531: }
1532:
1.41 markus 1533: /* This is our fake X11 server socket. */
1.127 itojun 1534: static void
1.367 djm 1535: channel_post_x11_listener(struct ssh *ssh, Channel *c,
1536: fd_set *readset, fd_set *writeset)
1.41 markus 1537: {
1.113 markus 1538: Channel *nc;
1.285 djm 1539: struct sockaddr_storage addr;
1.367 djm 1540: int r, newsock, oerrno, remote_port;
1.41 markus 1541: socklen_t addrlen;
1.85 markus 1542: char buf[16384], *remote_ipaddr;
1.25 markus 1543:
1.367 djm 1544: if (!FD_ISSET(c->sock, readset))
1545: return;
1546:
1547: debug("X11 connection requested.");
1548: addrlen = sizeof(addr);
1549: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1550: if (c->single_connection) {
1551: oerrno = errno;
1552: debug2("single_connection: closing X11 listener.");
1553: channel_close_fd(ssh, &c->sock);
1554: chan_mark_dead(ssh, c);
1555: errno = oerrno;
1556: }
1557: if (newsock < 0) {
1558: if (errno != EINTR && errno != EWOULDBLOCK &&
1559: errno != ECONNABORTED)
1560: error("accept: %.100s", strerror(errno));
1561: if (errno == EMFILE || errno == ENFILE)
1562: c->notbefore = monotime() + 1;
1563: return;
1564: }
1565: set_nodelay(newsock);
1566: remote_ipaddr = get_peer_ipaddr(newsock);
1567: remote_port = get_peer_port(newsock);
1568: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1569: remote_ipaddr, remote_port);
1570:
1571: nc = channel_new(ssh, "accepted x11 socket",
1572: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1573: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1574: open_preamble(ssh, __func__, nc, "x11");
1575: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0) {
1576: fatal("%s: channel %i: reply %s", __func__,
1577: c->self, ssh_err(r));
1578: }
1579: if ((datafellows & SSH_BUG_X11FWD) != 0)
1580: debug2("channel %d: ssh2 x11 bug compat mode", nc->self);
1581: else if ((r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1582: fatal("%s: channel %i: reply %s", __func__,
1583: c->self, ssh_err(r));
1.41 markus 1584: }
1.367 djm 1585: if ((r = sshpkt_send(ssh)) != 0)
1586: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1587: free(remote_ipaddr);
1.41 markus 1588: }
1.25 markus 1589:
1.127 itojun 1590: static void
1.367 djm 1591: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1592: {
1.328 djm 1593: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1594: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1595: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1596: int remote_port = get_peer_port(c->sock);
1.367 djm 1597: int r;
1.303 djm 1598:
1599: if (remote_port == -1) {
1600: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1601: free(remote_ipaddr);
1.303 djm 1602: remote_ipaddr = xstrdup("127.0.0.1");
1603: remote_port = 65535;
1604: }
1.103 markus 1605:
1.367 djm 1606: free(c->remote_name);
1607: xasprintf(&c->remote_name,
1.103 markus 1608: "%s: listening port %d for %.100s port %d, "
1.328 djm 1609: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1610: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1611: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1612:
1.367 djm 1613: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1614: if (strcmp(rtype, "direct-tcpip") == 0) {
1615: /* target host, port */
1.367 djm 1616: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1617: (r = sshpkt_put_u32(ssh, c->host_port)) != 0) {
1618: fatal("%s: channel %i: reply %s", __func__,
1619: c->self, ssh_err(r));
1620: }
1.358 djm 1621: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1622: /* target path */
1.367 djm 1623: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1624: fatal("%s: channel %i: reply %s", __func__,
1625: c->self, ssh_err(r));
1626: }
1.358 djm 1627: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1628: /* listen path */
1.367 djm 1629: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1630: fatal("%s: channel %i: reply %s", __func__,
1631: c->self, ssh_err(r));
1632: }
1.103 markus 1633: } else {
1.358 djm 1634: /* listen address, port */
1.367 djm 1635: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1636: (r = sshpkt_put_u32(ssh, local_port)) != 0) {
1637: fatal("%s: channel %i: reply %s", __func__,
1638: c->self, ssh_err(r));
1639: }
1.358 djm 1640: }
1641: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1642: /* reserved for future owner/mode info */
1.367 djm 1643: if ((r = sshpkt_put_cstring(ssh, "")) != 0) {
1644: fatal("%s: channel %i: reply %s", __func__,
1645: c->self, ssh_err(r));
1646: }
1.358 djm 1647: } else {
1648: /* originator host and port */
1.367 djm 1649: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1650: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0) {
1651: fatal("%s: channel %i: reply %s", __func__,
1652: c->self, ssh_err(r));
1653: }
1.103 markus 1654: }
1.367 djm 1655: if ((r = sshpkt_send(ssh)) != 0)
1656: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1.321 djm 1657: free(remote_ipaddr);
1.328 djm 1658: free(local_ipaddr);
1.103 markus 1659: }
1660:
1.347 djm 1661: void
1.367 djm 1662: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1663: {
1.367 djm 1664: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1665: }
1666:
1.41 markus 1667: /*
1668: * This socket is listening for connections to a forwarded TCP/IP port.
1669: */
1.127 itojun 1670: static void
1.367 djm 1671: channel_post_port_listener(struct ssh *ssh, Channel *c,
1672: fd_set *readset, fd_set *writeset)
1.41 markus 1673: {
1.103 markus 1674: Channel *nc;
1.285 djm 1675: struct sockaddr_storage addr;
1.113 markus 1676: int newsock, nextstate;
1.41 markus 1677: socklen_t addrlen;
1.103 markus 1678: char *rtype;
1.73 markus 1679:
1.367 djm 1680: if (!FD_ISSET(c->sock, readset))
1681: return;
1682:
1683: debug("Connection to port %d forwarding to %.100s port %d requested.",
1684: c->listening_port, c->path, c->host_port);
1.103 markus 1685:
1.367 djm 1686: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1687: nextstate = SSH_CHANNEL_OPENING;
1688: rtype = "forwarded-tcpip";
1689: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1690: nextstate = SSH_CHANNEL_OPENING;
1691: rtype = "forwarded-streamlocal@openssh.com";
1692: } else if (c->host_port == PORT_STREAMLOCAL) {
1693: nextstate = SSH_CHANNEL_OPENING;
1694: rtype = "direct-streamlocal@openssh.com";
1695: } else if (c->host_port == 0) {
1696: nextstate = SSH_CHANNEL_DYNAMIC;
1697: rtype = "dynamic-tcpip";
1698: } else {
1699: nextstate = SSH_CHANNEL_OPENING;
1700: rtype = "direct-tcpip";
1701: }
1.103 markus 1702:
1.367 djm 1703: addrlen = sizeof(addr);
1704: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1705: if (newsock < 0) {
1706: if (errno != EINTR && errno != EWOULDBLOCK &&
1707: errno != ECONNABORTED)
1708: error("accept: %.100s", strerror(errno));
1709: if (errno == EMFILE || errno == ENFILE)
1710: c->notbefore = monotime() + 1;
1711: return;
1.41 markus 1712: }
1.367 djm 1713: if (c->host_port != PORT_STREAMLOCAL)
1714: set_nodelay(newsock);
1715: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1716: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1717: nc->listening_port = c->listening_port;
1718: nc->host_port = c->host_port;
1719: if (c->path != NULL)
1720: nc->path = xstrdup(c->path);
1721:
1722: if (nextstate != SSH_CHANNEL_DYNAMIC)
1723: port_open_helper(ssh, nc, rtype);
1.41 markus 1724: }
1.25 markus 1725:
1.41 markus 1726: /*
1727: * This is the authentication agent socket listening for connections from
1728: * clients.
1729: */
1.127 itojun 1730: static void
1.367 djm 1731: channel_post_auth_listener(struct ssh *ssh, Channel *c,
1732: fd_set *readset, fd_set *writeset)
1.41 markus 1733: {
1.113 markus 1734: Channel *nc;
1.367 djm 1735: int r, newsock;
1.285 djm 1736: struct sockaddr_storage addr;
1.41 markus 1737: socklen_t addrlen;
1.25 markus 1738:
1.367 djm 1739: if (!FD_ISSET(c->sock, readset))
1740: return;
1741:
1742: addrlen = sizeof(addr);
1743: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1744: if (newsock < 0) {
1745: error("accept from auth socket: %.100s", strerror(errno));
1746: if (errno == EMFILE || errno == ENFILE)
1747: c->notbefore = monotime() + 1;
1748: return;
1.41 markus 1749: }
1.367 djm 1750: nc = channel_new(ssh, "accepted auth socket",
1751: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1752: c->local_window_max, c->local_maxpacket,
1753: 0, "accepted auth socket", 1);
1754: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1755: if ((r = sshpkt_send(ssh)) != 0)
1756: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.41 markus 1757: }
1.25 markus 1758:
1.127 itojun 1759: static void
1.367 djm 1760: channel_post_connecting(struct ssh *ssh, Channel *c,
1761: fd_set *readset, fd_set *writeset)
1.75 markus 1762: {
1.372 markus 1763: int err = 0, sock, isopen, r;
1.129 stevesk 1764: socklen_t sz = sizeof(err);
1.114 markus 1765:
1.367 djm 1766: if (!FD_ISSET(c->sock, writeset))
1767: return;
1.368 djm 1768: if (!c->have_remote_id)
1769: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.372 markus 1770: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1771: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.367 djm 1772: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1773: err = errno;
1774: error("getsockopt SO_ERROR failed");
1775: }
1776: if (err == 0) {
1777: debug("channel %d: connected to %s port %d",
1778: c->self, c->connect_ctx.host, c->connect_ctx.port);
1779: channel_connect_ctx_free(&c->connect_ctx);
1780: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1781: if (isopen) {
1782: /* no message necessary */
1783: } else {
1784: if ((r = sshpkt_start(ssh,
1785: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1786: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1787: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1788: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1789: (r = sshpkt_put_u32(ssh, c->local_maxpacket))
1790: != 0)
1791: fatal("%s: channel %i: confirm: %s", __func__,
1792: c->self, ssh_err(r));
1793: if ((r = sshpkt_send(ssh)) != 0)
1794: fatal("%s: channel %i: %s", __func__, c->self,
1795: ssh_err(r));
1.367 djm 1796: }
1797: } else {
1798: debug("channel %d: connection failed: %s",
1799: c->self, strerror(err));
1800: /* Try next address, if any */
1801: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1802: close(c->sock);
1803: c->sock = c->rfd = c->wfd = sock;
1804: channel_find_maxfd(ssh->chanctxt);
1805: return;
1806: }
1807: /* Exhausted all addresses */
1808: error("connect_to %.100s port %d: failed.",
1809: c->connect_ctx.host, c->connect_ctx.port);
1810: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1811: if (isopen) {
1812: rdynamic_close(ssh, c);
1813: } else {
1814: if ((r = sshpkt_start(ssh,
1815: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1816: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1817: (r = sshpkt_put_u32(ssh, SSH2_OPEN_CONNECT_FAILED))
1818: != 0)
1819: fatal("%s: channel %i: failure: %s", __func__,
1820: c->self, ssh_err(r));
1821: if ((datafellows & SSH_BUG_OPENFAILURE) == 0 &&
1822: ((r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1823: (r = sshpkt_put_cstring(ssh, "")) != 0))
1824: fatal("%s: channel %i: failure: %s", __func__,
1825: c->self, ssh_err(r));
1826: if ((r = sshpkt_send(ssh)) != 0)
1827: fatal("%s: channel %i: %s", __func__, c->self,
1828: ssh_err(r));
1829: chan_mark_dead(ssh, c);
1.75 markus 1830: }
1831: }
1832: }
1833:
1.127 itojun 1834: static int
1.367 djm 1835: channel_handle_rfd(struct ssh *ssh, Channel *c,
1836: fd_set *readset, fd_set *writeset)
1.41 markus 1837: {
1.214 markus 1838: char buf[CHAN_RBUF];
1.367 djm 1839: ssize_t len;
1840: int r;
1.25 markus 1841:
1.367 djm 1842: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
1843: return 1;
1844:
1845: len = read(c->rfd, buf, sizeof(buf));
1846: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1847: return 1;
1848: if (len <= 0) {
1849: debug2("channel %d: read<=0 rfd %d len %zd",
1850: c->self, c->rfd, len);
1851: if (c->type != SSH_CHANNEL_OPEN) {
1852: debug2("channel %d: not open", c->self);
1853: chan_mark_dead(ssh, c);
1.41 markus 1854: return -1;
1.65 markus 1855: } else {
1.367 djm 1856: chan_read_failed(ssh, c);
1.65 markus 1857: }
1.367 djm 1858: return -1;
1859: }
1860: if (c->input_filter != NULL) {
1861: if (c->input_filter(ssh, c, buf, len) == -1) {
1862: debug2("channel %d: filter stops", c->self);
1863: chan_read_failed(ssh, c);
1864: }
1865: } else if (c->datagram) {
1866: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1867: fatal("%s: channel %d: put datagram: %s", __func__,
1868: c->self, ssh_err(r));
1869: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
1870: fatal("%s: channel %d: put data: %s", __func__,
1871: c->self, ssh_err(r));
1.41 markus 1872: }
1873: return 1;
1874: }
1.241 deraadt 1875:
1.127 itojun 1876: static int
1.367 djm 1877: channel_handle_wfd(struct ssh *ssh, Channel *c,
1878: fd_set *readset, fd_set *writeset)
1.41 markus 1879: {
1.95 markus 1880: struct termios tio;
1.367 djm 1881: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1882: size_t dlen, olen = 0;
1883: int r, len;
1884:
1885: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
1886: sshbuf_len(c->output) == 0)
1887: return 1;
1.25 markus 1888:
1.41 markus 1889: /* Send buffered output data to the socket. */
1.367 djm 1890: olen = sshbuf_len(c->output);
1891: if (c->output_filter != NULL) {
1892: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1893: debug2("channel %d: filter stops", c->self);
1894: if (c->type != SSH_CHANNEL_OPEN)
1895: chan_mark_dead(ssh, c);
1896: else
1897: chan_write_failed(ssh, c);
1898: return -1;
1.231 reyk 1899: }
1.367 djm 1900: } else if (c->datagram) {
1901: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1902: fatal("%s: channel %d: get datagram: %s", __func__,
1903: c->self, ssh_err(r));
1.369 djm 1904: buf = data;
1.367 djm 1905: } else {
1906: buf = data = sshbuf_mutable_ptr(c->output);
1907: dlen = sshbuf_len(c->output);
1908: }
1.231 reyk 1909:
1.367 djm 1910: if (c->datagram) {
1911: /* ignore truncated writes, datagrams might get lost */
1.374 djm 1912: len = write(c->wfd, buf, dlen);
1.367 djm 1913: free(data);
1.53 markus 1914: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1915: return 1;
1.367 djm 1916: if (len <= 0)
1917: goto write_fail;
1918: goto out;
1919: }
1920:
1921: len = write(c->wfd, buf, dlen);
1922: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1923: return 1;
1924: if (len <= 0) {
1925: write_fail:
1926: if (c->type != SSH_CHANNEL_OPEN) {
1927: debug2("channel %d: not open", c->self);
1928: chan_mark_dead(ssh, c);
1.41 markus 1929: return -1;
1.367 djm 1930: } else {
1931: chan_write_failed(ssh, c);
1.91 markus 1932: }
1.367 djm 1933: return -1;
1934: }
1935: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
1936: if (tcgetattr(c->wfd, &tio) == 0 &&
1937: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1938: /*
1939: * Simulate echo to reduce the impact of
1940: * traffic analysis. We need to match the
1941: * size of a SSH2_MSG_CHANNEL_DATA message
1942: * (4 byte channel id + buf)
1943: */
1944: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
1945: (r = sshpkt_send(ssh)) != 0)
1946: fatal("%s: channel %d: ignore: %s",
1947: __func__, c->self, ssh_err(r));
1.25 markus 1948: }
1.367 djm 1949: }
1950: if ((r = sshbuf_consume(c->output, len)) != 0) {
1951: fatal("%s: channel %d: consume: %s",
1952: __func__, c->self, ssh_err(r));
1.44 markus 1953: }
1.309 djm 1954: out:
1.367 djm 1955: c->local_consumed += olen - sshbuf_len(c->output);
1956:
1957: return 1;
1958: }
1959:
1960: static int
1961: channel_handle_efd_write(struct ssh *ssh, Channel *c,
1962: fd_set *readset, fd_set *writeset)
1963: {
1964: int r;
1965: ssize_t len;
1966:
1967: if (!FD_ISSET(c->efd, writeset) || sshbuf_len(c->extended) == 0)
1968: return 1;
1969:
1970: len = write(c->efd, sshbuf_ptr(c->extended),
1971: sshbuf_len(c->extended));
1972: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1973: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1974: return 1;
1975: if (len <= 0) {
1976: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1977: channel_close_fd(ssh, &c->efd);
1978: } else {
1979: if ((r = sshbuf_consume(c->extended, len)) != 0) {
1980: fatal("%s: channel %d: consume: %s",
1981: __func__, c->self, ssh_err(r));
1982: }
1983: c->local_consumed += len;
1984: }
1.44 markus 1985: return 1;
1986: }
1.241 deraadt 1987:
1.127 itojun 1988: static int
1.367 djm 1989: channel_handle_efd_read(struct ssh *ssh, Channel *c,
1990: fd_set *readset, fd_set *writeset)
1.44 markus 1991: {
1.214 markus 1992: char buf[CHAN_RBUF];
1.367 djm 1993: int r;
1994: ssize_t len;
1995:
1996: if (!FD_ISSET(c->efd, readset))
1997: return 1;
1.44 markus 1998:
1.367 djm 1999: len = read(c->efd, buf, sizeof(buf));
2000: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
2001: if (len < 0 && (errno == EINTR || errno == EAGAIN))
2002: return 1;
2003: if (len <= 0) {
2004: debug2("channel %d: closing read-efd %d",
2005: c->self, c->efd);
2006: channel_close_fd(ssh, &c->efd);
2007: } else {
2008: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
2009: debug3("channel %d: discard efd",
2010: c->self);
2011: } else if ((r = sshbuf_put(c->extended, buf, len)) != 0) {
2012: fatal("%s: channel %d: append: %s",
2013: __func__, c->self, ssh_err(r));
1.44 markus 2014: }
2015: }
2016: return 1;
2017: }
1.241 deraadt 2018:
1.127 itojun 2019: static int
1.367 djm 2020: channel_handle_efd(struct ssh *ssh, Channel *c,
2021: fd_set *readset, fd_set *writeset)
1.44 markus 2022: {
1.367 djm 2023: if (c->efd == -1)
2024: return 1;
2025:
2026: /** XXX handle drain efd, too */
2027:
2028: if (c->extended_usage == CHAN_EXTENDED_WRITE)
2029: return channel_handle_efd_write(ssh, c, readset, writeset);
2030: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2031: c->extended_usage == CHAN_EXTENDED_IGNORE)
2032: return channel_handle_efd_read(ssh, c, readset, writeset);
2033:
2034: return 1;
2035: }
2036:
2037: static int
2038: channel_check_window(struct ssh *ssh, Channel *c)
2039: {
2040: int r;
2041:
1.104 markus 2042: if (c->type == SSH_CHANNEL_OPEN &&
2043: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2044: ((c->local_window_max - c->local_window >
1.269 markus 2045: c->local_maxpacket*3) ||
2046: c->local_window < c->local_window_max/2) &&
1.44 markus 2047: c->local_consumed > 0) {
1.368 djm 2048: if (!c->have_remote_id)
2049: fatal(":%s: channel %d: no remote id",
2050: __func__, c->self);
1.367 djm 2051: if ((r = sshpkt_start(ssh,
2052: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2053: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2054: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2055: (r = sshpkt_send(ssh)) != 0) {
2056: fatal("%s: channel %i: %s", __func__,
2057: c->self, ssh_err(r));
2058: }
1.70 markus 2059: debug2("channel %d: window %d sent adjust %d",
1.44 markus 2060: c->self, c->local_window,
2061: c->local_consumed);
2062: c->local_window += c->local_consumed;
2063: c->local_consumed = 0;
1.1 deraadt 2064: }
1.41 markus 2065: return 1;
1.1 deraadt 2066: }
2067:
1.127 itojun 2068: static void
1.367 djm 2069: channel_post_open(struct ssh *ssh, Channel *c,
2070: fd_set *readset, fd_set *writeset)
1.41 markus 2071: {
1.367 djm 2072: channel_handle_rfd(ssh, c, readset, writeset);
2073: channel_handle_wfd(ssh, c, readset, writeset);
2074: channel_handle_efd(ssh, c, readset, writeset);
2075: channel_check_window(ssh, c);
1.44 markus 2076: }
2077:
1.302 djm 2078: static u_int
1.367 djm 2079: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2080: {
2081: char buf[CHAN_RBUF];
1.367 djm 2082: ssize_t len;
1.302 djm 2083: u_int rlen;
1.367 djm 2084: int r;
1.302 djm 2085:
1.367 djm 2086: if (sshbuf_len(c->input) < need) {
2087: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2088: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.349 naddy 2089: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2090: return sshbuf_len(c->input);
1.302 djm 2091: if (len <= 0) {
1.367 djm 2092: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2093: c->self, c->rfd, len);
1.367 djm 2094: chan_read_failed(ssh, c);
1.349 naddy 2095: return 0;
1.367 djm 2096: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
2097: fatal("%s: channel %d: append: %s",
2098: __func__, c->self, ssh_err(r));
2099: }
1.302 djm 2100: }
1.367 djm 2101: return sshbuf_len(c->input);
1.302 djm 2102: }
2103:
2104: static void
1.367 djm 2105: channel_post_mux_client_read(struct ssh *ssh, Channel *c,
2106: fd_set *readset, fd_set *writeset)
1.302 djm 2107: {
2108: u_int need;
2109:
1.367 djm 2110: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
2111: return;
2112: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2113: return;
2114: if (c->mux_pause)
2115: return;
2116:
2117: /*
2118: * Don't not read past the precise end of packets to
2119: * avoid disrupting fd passing.
2120: */
2121: if (read_mux(ssh, c, 4) < 4) /* read header */
2122: return;
2123: /* XXX sshbuf_peek_u32 */
2124: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2125: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2126: if (need > CHANNEL_MUX_MAX_PACKET) {
2127: debug2("channel %d: packet too big %u > %u",
2128: c->self, CHANNEL_MUX_MAX_PACKET, need);
2129: chan_rcvd_oclose(ssh, c);
2130: return;
2131: }
2132: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2133: return;
2134: if (c->mux_rcb(ssh, c) != 0) {
2135: debug("channel %d: mux_rcb failed", c->self);
2136: chan_mark_dead(ssh, c);
2137: return;
1.302 djm 2138: }
1.367 djm 2139: }
2140:
2141: static void
2142: channel_post_mux_client_write(struct ssh *ssh, Channel *c,
2143: fd_set *readset, fd_set *writeset)
2144: {
2145: ssize_t len;
2146: int r;
1.302 djm 2147:
1.367 djm 2148: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
2149: sshbuf_len(c->output) == 0)
2150: return;
2151:
2152: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
2153: if (len < 0 && (errno == EINTR || errno == EAGAIN))
2154: return;
2155: if (len <= 0) {
2156: chan_mark_dead(ssh, c);
2157: return;
1.302 djm 2158: }
1.367 djm 2159: if ((r = sshbuf_consume(c->output, len)) != 0)
2160: fatal("%s: channel %d: consume: %s", __func__,
2161: c->self, ssh_err(r));
2162: }
2163:
2164: static void
2165: channel_post_mux_client(struct ssh *ssh, Channel *c,
2166: fd_set *readset, fd_set *writeset)
2167: {
2168: channel_post_mux_client_read(ssh, c, readset, writeset);
2169: channel_post_mux_client_write(ssh, c, readset, writeset);
1.302 djm 2170: }
2171:
2172: static void
1.367 djm 2173: channel_post_mux_listener(struct ssh *ssh, Channel *c,
2174: fd_set *readset, fd_set *writeset)
1.302 djm 2175: {
2176: Channel *nc;
2177: struct sockaddr_storage addr;
2178: socklen_t addrlen;
2179: int newsock;
2180: uid_t euid;
2181: gid_t egid;
2182:
2183: if (!FD_ISSET(c->sock, readset))
2184: return;
2185:
2186: debug("multiplexing control connection");
2187:
2188: /*
2189: * Accept connection on control socket
2190: */
2191: memset(&addr, 0, sizeof(addr));
2192: addrlen = sizeof(addr);
2193: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2194: &addrlen)) == -1) {
2195: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 2196: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2197: c->notbefore = monotime() + 1;
1.302 djm 2198: return;
2199: }
2200:
2201: if (getpeereid(newsock, &euid, &egid) < 0) {
2202: error("%s getpeereid failed: %s", __func__,
2203: strerror(errno));
2204: close(newsock);
2205: return;
2206: }
2207: if ((euid != 0) && (getuid() != euid)) {
2208: error("multiplex uid mismatch: peer euid %u != uid %u",
2209: (u_int)euid, (u_int)getuid());
2210: close(newsock);
2211: return;
2212: }
1.367 djm 2213: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2214: newsock, newsock, -1, c->local_window_max,
2215: c->local_maxpacket, 0, "mux-control", 1);
2216: nc->mux_rcb = c->mux_rcb;
1.367 djm 2217: debug3("%s: new mux channel %d fd %d", __func__, nc->self, nc->sock);
1.302 djm 2218: /* establish state */
1.367 djm 2219: nc->mux_rcb(ssh, nc);
1.302 djm 2220: /* mux state transitions must not elicit protocol messages */
2221: nc->flags |= CHAN_LOCAL;
2222: }
2223:
1.127 itojun 2224: static void
1.367 djm 2225: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2226: {
1.367 djm 2227: chan_fn **pre, **post;
2228:
2229: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
2230: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
2231: fatal("%s: allocation failed", __func__);
2232:
2233: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2234: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2235: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2236: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2237: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2238: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2239: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2240: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2241: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2242: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2243: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2244: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2245: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2246:
2247: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2248: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2249: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2250: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2251: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2252: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2253: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2254: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2255: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2256: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2257: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2258: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2259:
1.367 djm 2260: sc->channel_pre = pre;
2261: sc->channel_post = post;
1.44 markus 2262: }
2263:
1.140 markus 2264: /* gc dead channels */
2265: static void
1.367 djm 2266: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2267: {
2268: if (c == NULL)
2269: return;
2270: if (c->detach_user != NULL) {
1.367 djm 2271: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2272: return;
1.194 markus 2273: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2274: c->detach_user(ssh, c->self, NULL);
1.140 markus 2275: /* if we still have a callback */
2276: if (c->detach_user != NULL)
2277: return;
1.194 markus 2278: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2279: }
1.367 djm 2280: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2281: return;
1.194 markus 2282: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2283: channel_free(ssh, c);
1.140 markus 2284: }
2285:
1.367 djm 2286: enum channel_table { CHAN_PRE, CHAN_POST };
2287:
1.127 itojun 2288: static void
1.367 djm 2289: channel_handler(struct ssh *ssh, int table,
1.366 djm 2290: fd_set *readset, fd_set *writeset, time_t *unpause_secs)
1.41 markus 2291: {
1.367 djm 2292: struct ssh_channels *sc = ssh->chanctxt;
2293: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2294: u_int i, oalloc;
1.41 markus 2295: Channel *c;
1.317 djm 2296: time_t now;
1.25 markus 2297:
1.322 dtucker 2298: now = monotime();
1.317 djm 2299: if (unpause_secs != NULL)
2300: *unpause_secs = 0;
1.367 djm 2301: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2302: c = sc->channels[i];
1.113 markus 2303: if (c == NULL)
1.41 markus 2304: continue;
1.299 markus 2305: if (c->delayed) {
1.367 djm 2306: if (table == CHAN_PRE)
1.299 markus 2307: c->delayed = 0;
2308: else
2309: continue;
2310: }
1.317 djm 2311: if (ftab[c->type] != NULL) {
2312: /*
2313: * Run handlers that are not paused.
2314: */
2315: if (c->notbefore <= now)
1.367 djm 2316: (*ftab[c->type])(ssh, c, readset, writeset);
1.317 djm 2317: else if (unpause_secs != NULL) {
2318: /*
2319: * Collect the time that the earliest
2320: * channel comes off pause.
2321: */
2322: debug3("%s: chan %d: skip for %d more seconds",
2323: __func__, c->self,
2324: (int)(c->notbefore - now));
2325: if (*unpause_secs == 0 ||
2326: (c->notbefore - now) < *unpause_secs)
2327: *unpause_secs = c->notbefore - now;
2328: }
2329: }
1.367 djm 2330: channel_garbage_collect(ssh, c);
1.1 deraadt 2331: }
1.317 djm 2332: if (unpause_secs != NULL && *unpause_secs != 0)
2333: debug3("%s: first channel unpauses in %d seconds",
2334: __func__, (int)*unpause_secs);
1.1 deraadt 2335: }
2336:
1.121 markus 2337: /*
1.372 markus 2338: * Create sockets before allocating the select bitmasks.
2339: * This is necessary for things that need to happen after reading
2340: * the network-input but before channel_prepare_select().
2341: */
2342: static void
2343: channel_before_prepare_select(struct ssh *ssh)
2344: {
2345: struct ssh_channels *sc = ssh->chanctxt;
2346: Channel *c;
2347: u_int i, oalloc;
2348:
2349: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2350: c = sc->channels[i];
2351: if (c == NULL)
2352: continue;
2353: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
2354: channel_before_prepare_select_rdynamic(ssh, c);
2355: }
2356: }
2357:
2358: /*
1.121 markus 2359: * Allocate/update select bitmasks and add any bits relevant to channels in
2360: * select bitmasks.
2361: */
1.49 markus 2362: void
1.366 djm 2363: channel_prepare_select(struct ssh *ssh, fd_set **readsetp, fd_set **writesetp,
2364: int *maxfdp, u_int *nallocp, time_t *minwait_secs)
1.41 markus 2365: {
1.243 djm 2366: u_int n, sz, nfdset;
1.84 markus 2367:
1.372 markus 2368: channel_before_prepare_select(ssh); /* might update channel_max_fd */
2369:
1.367 djm 2370: n = MAXIMUM(*maxfdp, ssh->chanctxt->channel_max_fd);
1.84 markus 2371:
1.243 djm 2372: nfdset = howmany(n+1, NFDBITS);
2373: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2374: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2375: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2376: sz = nfdset * sizeof(fd_mask);
2377:
1.132 markus 2378: /* perhaps check sz < nalloc/2 and shrink? */
2379: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2380: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2381: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2382: *nallocp = sz;
1.84 markus 2383: }
1.132 markus 2384: *maxfdp = n;
1.84 markus 2385: memset(*readsetp, 0, sz);
2386: memset(*writesetp, 0, sz);
2387:
1.366 djm 2388: if (!ssh_packet_is_rekeying(ssh))
1.367 djm 2389: channel_handler(ssh, CHAN_PRE, *readsetp, *writesetp,
1.317 djm 2390: minwait_secs);
1.41 markus 2391: }
2392:
1.121 markus 2393: /*
2394: * After select, perform any appropriate operations for channels which have
2395: * events pending.
2396: */
1.49 markus 2397: void
1.366 djm 2398: channel_after_select(struct ssh *ssh, fd_set *readset, fd_set *writeset)
1.41 markus 2399: {
1.367 djm 2400: channel_handler(ssh, CHAN_POST, readset, writeset, NULL);
2401: }
2402:
2403: /*
2404: * Enqueue data for channels with open or draining c->input.
2405: */
2406: static void
2407: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2408: {
1.373 djm 2409: size_t len, plen;
2410: const u_char *pkt;
1.367 djm 2411: int r;
2412:
2413: if ((len = sshbuf_len(c->input)) == 0) {
2414: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2415: /*
2416: * input-buffer is empty and read-socket shutdown:
2417: * tell peer, that we will not send more data:
2418: * send IEOF.
2419: * hack for extended data: delay EOF if EFD still
2420: * in use.
2421: */
2422: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2423: debug2("channel %d: "
2424: "ibuf_empty delayed efd %d/(%zu)",
2425: c->self, c->efd, sshbuf_len(c->extended));
2426: else
2427: chan_ibuf_empty(ssh, c);
2428: }
2429: return;
2430: }
2431:
1.368 djm 2432: if (!c->have_remote_id)
2433: fatal(":%s: channel %d: no remote id", __func__, c->self);
2434:
1.367 djm 2435: if (c->datagram) {
2436: /* Check datagram will fit; drop if not */
1.373 djm 2437: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
2438: fatal("%s: channel %d: get datagram: %s", __func__,
1.367 djm 2439: c->self, ssh_err(r));
2440: /*
2441: * XXX this does tail-drop on the datagram queue which is
2442: * usually suboptimal compared to head-drop. Better to have
2443: * backpressure at read time? (i.e. read + discard)
2444: */
1.373 djm 2445: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2446: debug("channel %d: datagram too big", c->self);
2447: return;
2448: }
2449: /* Enqueue it */
2450: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2451: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2452: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.367 djm 2453: (r = sshpkt_send(ssh)) != 0) {
2454: fatal("%s: channel %i: datagram: %s", __func__,
2455: c->self, ssh_err(r));
2456: }
1.373 djm 2457: c->remote_window -= plen;
1.367 djm 2458: return;
2459: }
2460:
2461: /* Enqueue packet for buffered data. */
2462: if (len > c->remote_window)
2463: len = c->remote_window;
2464: if (len > c->remote_maxpacket)
2465: len = c->remote_maxpacket;
2466: if (len == 0)
2467: return;
2468: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2469: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2470: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
2471: (r = sshpkt_send(ssh)) != 0) {
2472: fatal("%s: channel %i: data: %s", __func__,
2473: c->self, ssh_err(r));
2474: }
2475: if ((r = sshbuf_consume(c->input, len)) != 0)
2476: fatal("%s: channel %i: consume: %s", __func__,
2477: c->self, ssh_err(r));
2478: c->remote_window -= len;
1.41 markus 2479: }
2480:
1.367 djm 2481: /*
2482: * Enqueue data for channels with open c->extended in read mode.
2483: */
2484: static void
2485: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2486: {
2487: size_t len;
2488: int r;
2489:
2490: if ((len = sshbuf_len(c->extended)) == 0)
2491: return;
2492:
2493: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2494: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2495: if (len > c->remote_window)
2496: len = c->remote_window;
2497: if (len > c->remote_maxpacket)
2498: len = c->remote_maxpacket;
2499: if (len == 0)
2500: return;
1.368 djm 2501: if (!c->have_remote_id)
2502: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.367 djm 2503: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2504: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2505: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2506: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
2507: (r = sshpkt_send(ssh)) != 0) {
2508: fatal("%s: channel %i: data: %s", __func__,
2509: c->self, ssh_err(r));
2510: }
2511: if ((r = sshbuf_consume(c->extended, len)) != 0)
2512: fatal("%s: channel %i: consume: %s", __func__,
2513: c->self, ssh_err(r));
2514: c->remote_window -= len;
2515: debug2("channel %d: sent ext data %zu", c->self, len);
2516: }
1.121 markus 2517:
1.84 markus 2518: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2519: void
1.367 djm 2520: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2521: {
1.367 djm 2522: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2523: Channel *c;
1.367 djm 2524: u_int i;
1.1 deraadt 2525:
1.367 djm 2526: for (i = 0; i < sc->channels_alloc; i++) {
2527: c = sc->channels[i];
1.113 markus 2528: if (c == NULL)
2529: continue;
1.37 markus 2530:
1.121 markus 2531: /*
2532: * We are only interested in channels that can have buffered
2533: * incoming data.
2534: */
1.358 djm 2535: if (c->type != SSH_CHANNEL_OPEN)
2536: continue;
2537: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2538: /* XXX is this true? */
1.367 djm 2539: debug3("channel %d: will not send data after close",
2540: c->self);
1.44 markus 2541: continue;
2542: }
1.25 markus 2543:
2544: /* Get the amount of buffered data for this channel. */
1.367 djm 2545: if (c->istate == CHAN_INPUT_OPEN ||
2546: c->istate == CHAN_INPUT_WAIT_DRAIN)
2547: channel_output_poll_input_open(ssh, c);
1.44 markus 2548: /* Send extended data, i.e. stderr */
1.358 djm 2549: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2550: c->extended_usage == CHAN_EXTENDED_READ)
2551: channel_output_poll_extended_read(ssh, c);
1.25 markus 2552: }
1.1 deraadt 2553: }
2554:
1.354 markus 2555: /* -- mux proxy support */
2556:
2557: /*
2558: * When multiplexing channel messages for mux clients we have to deal
2559: * with downstream messages from the mux client and upstream messages
2560: * from the ssh server:
2561: * 1) Handling downstream messages is straightforward and happens
2562: * in channel_proxy_downstream():
2563: * - We forward all messages (mostly) unmodified to the server.
2564: * - However, in order to route messages from upstream to the correct
2565: * downstream client, we have to replace the channel IDs used by the
2566: * mux clients with a unique channel ID because the mux clients might
2567: * use conflicting channel IDs.
2568: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2569: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2570: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2571: * with the newly allocated channel ID.
2572: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
2573: * channels and procesed by channel_proxy_upstream(). The local channel ID
2574: * is then translated back to the original mux client ID.
2575: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2576: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2577: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2578: * downstream mux client are removed.
2579: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2580: * requires more work, because they are not addressed to a specific
2581: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2582: * out whether the request is addressed to the local client or a
2583: * specific downstream client based on the listen-address/port.
2584: * 6) Agent and X11-Forwarding have a similar problem and are currenly
2585: * not supported as the matching session/channel cannot be identified
2586: * easily.
2587: */
2588:
2589: /*
2590: * receive packets from downstream mux clients:
2591: * channel callback fired on read from mux client, creates
2592: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2593: * on channel creation.
2594: */
2595: int
1.367 djm 2596: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2597: {
2598: Channel *c = NULL;
2599: struct sshbuf *original = NULL, *modified = NULL;
2600: const u_char *cp;
2601: char *ctype = NULL, *listen_host = NULL;
2602: u_char type;
2603: size_t have;
1.370 djm 2604: int ret = -1, r;
1.355 djm 2605: u_int id, remote_id, listen_port;
1.354 markus 2606:
1.367 djm 2607: /* sshbuf_dump(downstream->input, stderr); */
2608: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2609: != 0) {
2610: error("%s: malformed message: %s", __func__, ssh_err(r));
2611: return -1;
2612: }
2613: if (have < 2) {
2614: error("%s: short message", __func__);
2615: return -1;
2616: }
2617: type = cp[1];
2618: /* skip padlen + type */
2619: cp += 2;
2620: have -= 2;
2621: if (ssh_packet_log_type(type))
2622: debug3("%s: channel %u: down->up: type %u", __func__,
2623: downstream->self, type);
2624:
2625: switch (type) {
2626: case SSH2_MSG_CHANNEL_OPEN:
2627: if ((original = sshbuf_from(cp, have)) == NULL ||
2628: (modified = sshbuf_new()) == NULL) {
2629: error("%s: alloc", __func__);
2630: goto out;
2631: }
2632: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2633: (r = sshbuf_get_u32(original, &id)) != 0) {
2634: error("%s: parse error %s", __func__, ssh_err(r));
2635: goto out;
2636: }
1.367 djm 2637: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2638: -1, -1, -1, 0, 0, 0, ctype, 1);
2639: c->mux_ctx = downstream; /* point to mux client */
2640: c->mux_downstream_id = id; /* original downstream id */
2641: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2642: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2643: (r = sshbuf_putb(modified, original)) != 0) {
2644: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2645: channel_free(ssh, c);
1.354 markus 2646: goto out;
2647: }
2648: break;
2649: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2650: /*
2651: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2652: * need to parse 'remote_id' instead of 'ctype'.
2653: */
2654: if ((original = sshbuf_from(cp, have)) == NULL ||
2655: (modified = sshbuf_new()) == NULL) {
2656: error("%s: alloc", __func__);
2657: goto out;
2658: }
2659: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2660: (r = sshbuf_get_u32(original, &id)) != 0) {
2661: error("%s: parse error %s", __func__, ssh_err(r));
2662: goto out;
2663: }
1.367 djm 2664: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2665: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
2666: c->mux_ctx = downstream; /* point to mux client */
2667: c->mux_downstream_id = id;
2668: c->remote_id = remote_id;
1.368 djm 2669: c->have_remote_id = 1;
1.354 markus 2670: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2671: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2672: (r = sshbuf_putb(modified, original)) != 0) {
2673: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2674: channel_free(ssh, c);
1.354 markus 2675: goto out;
2676: }
2677: break;
2678: case SSH2_MSG_GLOBAL_REQUEST:
2679: if ((original = sshbuf_from(cp, have)) == NULL) {
2680: error("%s: alloc", __func__);
2681: goto out;
2682: }
2683: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
2684: error("%s: parse error %s", __func__, ssh_err(r));
2685: goto out;
2686: }
2687: if (strcmp(ctype, "tcpip-forward") != 0) {
2688: error("%s: unsupported request %s", __func__, ctype);
2689: goto out;
2690: }
2691: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2692: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2693: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
2694: error("%s: parse error %s", __func__, ssh_err(r));
2695: goto out;
2696: }
1.355 djm 2697: if (listen_port > 65535) {
2698: error("%s: tcpip-forward for %s: bad port %u",
2699: __func__, listen_host, listen_port);
2700: goto out;
2701: }
1.354 markus 2702: /* Record that connection to this host/port is permitted. */
1.370 djm 2703: fwd_perm_list_add(ssh, FWDPERM_USER, "<mux>", -1,
1.367 djm 2704: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 2705: listen_host = NULL;
2706: break;
2707: case SSH2_MSG_CHANNEL_CLOSE:
2708: if (have < 4)
2709: break;
2710: remote_id = PEEK_U32(cp);
1.367 djm 2711: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 2712: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 2713: channel_free(ssh, c);
1.354 markus 2714: else
2715: c->flags |= CHAN_CLOSE_SENT;
2716: }
2717: break;
2718: }
2719: if (modified) {
2720: if ((r = sshpkt_start(ssh, type)) != 0 ||
2721: (r = sshpkt_putb(ssh, modified)) != 0 ||
2722: (r = sshpkt_send(ssh)) != 0) {
2723: error("%s: send %s", __func__, ssh_err(r));
2724: goto out;
2725: }
2726: } else {
2727: if ((r = sshpkt_start(ssh, type)) != 0 ||
2728: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2729: (r = sshpkt_send(ssh)) != 0) {
2730: error("%s: send %s", __func__, ssh_err(r));
2731: goto out;
2732: }
2733: }
2734: ret = 0;
2735: out:
2736: free(ctype);
2737: free(listen_host);
2738: sshbuf_free(original);
2739: sshbuf_free(modified);
2740: return ret;
2741: }
2742:
2743: /*
2744: * receive packets from upstream server and de-multiplex packets
2745: * to correct downstream:
2746: * implemented as a helper for channel input handlers,
2747: * replaces local (proxy) channel ID with downstream channel ID.
2748: */
2749: int
1.363 markus 2750: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 2751: {
2752: struct sshbuf *b = NULL;
2753: Channel *downstream;
2754: const u_char *cp = NULL;
2755: size_t len;
2756: int r;
2757:
2758: /*
2759: * When receiving packets from the peer we need to check whether we
2760: * need to forward the packets to the mux client. In this case we
2761: * restore the orignal channel id and keep track of CLOSE messages,
2762: * so we can cleanup the channel.
2763: */
2764: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2765: return 0;
2766: if ((downstream = c->mux_ctx) == NULL)
2767: return 0;
2768: switch (type) {
2769: case SSH2_MSG_CHANNEL_CLOSE:
2770: case SSH2_MSG_CHANNEL_DATA:
2771: case SSH2_MSG_CHANNEL_EOF:
2772: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2773: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2774: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2775: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2776: case SSH2_MSG_CHANNEL_SUCCESS:
2777: case SSH2_MSG_CHANNEL_FAILURE:
2778: case SSH2_MSG_CHANNEL_REQUEST:
2779: break;
2780: default:
2781: debug2("%s: channel %u: unsupported type %u", __func__,
2782: c->self, type);
2783: return 0;
2784: }
2785: if ((b = sshbuf_new()) == NULL) {
2786: error("%s: alloc reply", __func__);
2787: goto out;
2788: }
2789: /* get remaining payload (after id) */
2790: cp = sshpkt_ptr(ssh, &len);
2791: if (cp == NULL) {
2792: error("%s: no packet", __func__);
2793: goto out;
2794: }
2795: /* translate id and send to muxclient */
2796: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2797: (r = sshbuf_put_u8(b, type)) != 0 ||
2798: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2799: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 2800: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.354 markus 2801: error("%s: compose for muxclient %s", __func__, ssh_err(r));
2802: goto out;
2803: }
2804: /* sshbuf_dump(b, stderr); */
2805: if (ssh_packet_log_type(type))
2806: debug3("%s: channel %u: up->down: type %u", __func__, c->self,
2807: type);
2808: out:
2809: /* update state */
2810: switch (type) {
2811: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2812: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 2813: if (cp && len > 4) {
1.354 markus 2814: c->remote_id = PEEK_U32(cp);
1.368 djm 2815: c->have_remote_id = 1;
2816: }
1.354 markus 2817: break;
2818: case SSH2_MSG_CHANNEL_CLOSE:
2819: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 2820: channel_free(ssh, c);
1.354 markus 2821: else
2822: c->flags |= CHAN_CLOSE_RCVD;
2823: break;
2824: }
2825: sshbuf_free(b);
2826: return 1;
2827: }
1.121 markus 2828:
2829: /* -- protocol input */
1.249 djm 2830:
1.367 djm 2831: /* Parse a channel ID from the current packet */
2832: static int
2833: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
2834: {
2835: u_int32_t id;
2836: int r;
2837:
2838: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
2839: error("%s: parse id: %s", where, ssh_err(r));
2840: ssh_packet_disconnect(ssh, "Invalid %s message", what);
2841: }
2842: if (id > INT_MAX) {
2843: error("%s: bad channel id %u: %s", where, id, ssh_err(r));
2844: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
2845: }
2846: return (int)id;
2847: }
2848:
2849: /* Lookup a channel from an ID in the current packet */
2850: static Channel *
2851: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
2852: {
2853: int id = channel_parse_id(ssh, where, what);
2854: Channel *c;
2855:
2856: if ((c = channel_lookup(ssh, id)) == NULL) {
2857: ssh_packet_disconnect(ssh,
2858: "%s packet referred to nonexistent channel %d", what, id);
2859: }
2860: return c;
2861: }
2862:
1.339 markus 2863: int
1.363 markus 2864: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2865: {
1.332 djm 2866: const u_char *data;
1.367 djm 2867: size_t data_len, win_len;
2868: Channel *c = channel_from_packet_id(ssh, __func__, "data");
2869: int r;
1.25 markus 2870:
1.363 markus 2871: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2872: return 0;
1.25 markus 2873:
2874: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2875: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 2876: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
2877: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 2878: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2879: return 0;
1.37 markus 2880:
1.25 markus 2881: /* Get the data. */
1.367 djm 2882: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0)
2883: fatal("%s: channel %d: get data: %s", __func__,
2884: c->self, ssh_err(r));
2885: ssh_packet_check_eom(ssh);
2886:
1.309 djm 2887: win_len = data_len;
2888: if (c->datagram)
2889: win_len += 4; /* string length header */
1.200 markus 2890:
2891: /*
1.367 djm 2892: * The sending side reduces its window as it sends data, so we
2893: * must 'fake' consumption of the data in order to ensure that window
2894: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 2895: */
1.358 djm 2896: if (c->ostate != CHAN_OUTPUT_OPEN) {
2897: c->local_window -= win_len;
2898: c->local_consumed += win_len;
1.339 markus 2899: return 0;
1.200 markus 2900: }
1.41 markus 2901:
1.358 djm 2902: if (win_len > c->local_maxpacket) {
1.367 djm 2903: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 2904: c->self, win_len, c->local_maxpacket);
1.367 djm 2905: return 0;
1.358 djm 2906: }
2907: if (win_len > c->local_window) {
1.367 djm 2908: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 2909: c->self, win_len, c->local_window);
2910: return 0;
1.44 markus 2911: }
1.358 djm 2912: c->local_window -= win_len;
2913:
1.367 djm 2914: if (c->datagram) {
2915: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
2916: fatal("%s: channel %d: append datagram: %s",
2917: __func__, c->self, ssh_err(r));
2918: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
2919: fatal("%s: channel %d: append data: %s",
2920: __func__, c->self, ssh_err(r));
2921:
1.339 markus 2922: return 0;
1.1 deraadt 2923: }
1.121 markus 2924:
1.339 markus 2925: int
1.363 markus 2926: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 2927: {
1.367 djm 2928: const u_char *data;
2929: size_t data_len;
2930: u_int32_t tcode;
2931: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
2932: int r;
1.44 markus 2933:
1.363 markus 2934: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2935: return 0;
1.44 markus 2936: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 2937: logit("channel %d: ext data for non open", c->self);
1.339 markus 2938: return 0;
1.172 markus 2939: }
2940: if (c->flags & CHAN_EOF_RCVD) {
2941: if (datafellows & SSH_BUG_EXTEOF)
1.367 djm 2942: debug("channel %d: accepting ext data after eof",
2943: c->self);
1.172 markus 2944: else
1.367 djm 2945: ssh_packet_disconnect(ssh, "Received extended_data "
2946: "after EOF on channel %d.", c->self);
2947: }
2948:
2949: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
2950: error("%s: parse tcode: %s", __func__, ssh_err(r));
2951: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 2952: }
2953: if (c->efd == -1 ||
2954: c->extended_usage != CHAN_EXTENDED_WRITE ||
2955: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2956: logit("channel %d: bad ext data", c->self);
1.339 markus 2957: return 0;
1.44 markus 2958: }
1.367 djm 2959: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0) {
2960: error("%s: parse data: %s", __func__, ssh_err(r));
2961: ssh_packet_disconnect(ssh, "Invalid extended_data message");
2962: }
2963: ssh_packet_check_eom(ssh);
2964:
1.44 markus 2965: if (data_len > c->local_window) {
1.367 djm 2966: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 2967: c->self, data_len, c->local_window);
1.339 markus 2968: return 0;
1.44 markus 2969: }
1.367 djm 2970: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
2971: /* XXX sshpkt_getb? */
2972: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
2973: error("%s: append: %s", __func__, ssh_err(r));
1.44 markus 2974: c->local_window -= data_len;
1.339 markus 2975: return 0;
1.44 markus 2976: }
2977:
1.339 markus 2978: int
1.363 markus 2979: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 2980: {
1.367 djm 2981: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
2982:
2983: ssh_packet_check_eom(ssh);
1.41 markus 2984:
1.363 markus 2985: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2986: return 0;
1.367 djm 2987: chan_rcvd_ieof(ssh, c);
1.133 markus 2988:
2989: /* XXX force input close */
1.156 markus 2990: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2991: debug("channel %d: FORCE input drain", c->self);
2992: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 2993: if (sshbuf_len(c->input) == 0)
2994: chan_ibuf_empty(ssh, c);
1.133 markus 2995: }
1.339 markus 2996: return 0;
1.41 markus 2997: }
1.1 deraadt 2998:
1.339 markus 2999: int
1.363 markus 3000: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3001: {
1.367 djm 3002: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.151 markus 3003:
1.363 markus 3004: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3005: return 0;
1.367 djm 3006: ssh_packet_check_eom(ssh);
3007: chan_rcvd_oclose(ssh, c);
1.339 markus 3008: return 0;
1.1 deraadt 3009: }
3010:
1.339 markus 3011: int
1.363 markus 3012: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3013: {
1.367 djm 3014: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3015: u_int32_t remote_window, remote_maxpacket;
3016: int r;
1.25 markus 3017:
1.363 markus 3018: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3019: return 0;
3020: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 3021: packet_disconnect("Received open confirmation for "
1.367 djm 3022: "non-opening channel %d.", c->self);
3023: /*
3024: * Record the remote channel number and mark that the channel
3025: * is now open.
3026: */
1.368 djm 3027: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3028: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.367 djm 3029: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0) {
3030: error("%s: window/maxpacket: %s", __func__, ssh_err(r));
3031: packet_disconnect("Invalid open confirmation message");
3032: }
3033: ssh_packet_check_eom(ssh);
3034:
1.368 djm 3035: c->have_remote_id = 1;
1.367 djm 3036: c->remote_window = remote_window;
3037: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3038: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3039: if (c->open_confirm) {
1.367 djm 3040: debug2("%s: channel %d: callback start", __func__, c->self);
3041: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
3042: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3043: }
1.358 djm 3044: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3045: c->remote_window, c->remote_maxpacket);
1.339 markus 3046: return 0;
1.1 deraadt 3047: }
3048:
1.127 itojun 3049: static char *
1.114 markus 3050: reason2txt(int reason)
3051: {
1.143 deraadt 3052: switch (reason) {
1.114 markus 3053: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3054: return "administratively prohibited";
3055: case SSH2_OPEN_CONNECT_FAILED:
3056: return "connect failed";
3057: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3058: return "unknown channel type";
3059: case SSH2_OPEN_RESOURCE_SHORTAGE:
3060: return "resource shortage";
3061: }
1.117 stevesk 3062: return "unknown reason";
1.114 markus 3063: }
3064:
1.339 markus 3065: int
1.363 markus 3066: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3067: {
1.367 djm 3068: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3069: u_int32_t reason;
3070: char *msg = NULL;
3071: int r;
1.25 markus 3072:
1.363 markus 3073: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3074: return 0;
3075: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 3076: packet_disconnect("Received open failure for "
1.367 djm 3077: "non-opening channel %d.", c->self);
3078: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
3079: error("%s: reason: %s", __func__, ssh_err(r));
3080: packet_disconnect("Invalid open failure message");
3081: }
3082: if ((datafellows & SSH_BUG_OPENFAILURE) == 0) {
3083: /* skip language */
3084: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.375 djm 3085: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0) {
1.367 djm 3086: error("%s: message/lang: %s", __func__, ssh_err(r));
3087: packet_disconnect("Invalid open failure message");
3088: }
1.358 djm 3089: }
1.367 djm 3090: ssh_packet_check_eom(ssh);
3091: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3092: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3093: free(msg);
3094: if (c->open_confirm) {
1.367 djm 3095: debug2("%s: channel %d: callback start", __func__, c->self);
3096: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
3097: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3098: }
1.291 djm 3099: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3100: chan_mark_dead(ssh, c);
1.339 markus 3101: return 0;
1.44 markus 3102: }
3103:
1.339 markus 3104: int
1.363 markus 3105: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3106: {
1.367 djm 3107: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3108: Channel *c;
1.367 djm 3109: u_int32_t adjust;
3110: u_int new_rwin;
3111: int r;
1.1 deraadt 3112:
1.367 djm 3113: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3114: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3115: return 0;
1.372 markus 3116: }
1.367 djm 3117:
1.363 markus 3118: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3119: return 0;
1.367 djm 3120: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0) {
3121: error("%s: adjust: %s", __func__, ssh_err(r));
3122: packet_disconnect("Invalid window adjust message");
3123: }
3124: ssh_packet_check_eom(ssh);
3125: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3126: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3127: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3128: c->self, adjust, c->remote_window);
3129: }
3130: c->remote_window = new_rwin;
1.339 markus 3131: return 0;
1.121 markus 3132: }
1.1 deraadt 3133:
1.339 markus 3134: int
1.363 markus 3135: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3136: {
1.367 djm 3137: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3138: Channel *c;
3139: struct channel_confirm *cc;
3140:
3141: /* Reset keepalive timeout */
1.296 andreas 3142: packet_set_alive_timeouts(0);
1.275 djm 3143:
1.367 djm 3144: debug2("%s: type %d id %d", __func__, type, id);
1.275 djm 3145:
1.367 djm 3146: if ((c = channel_lookup(ssh, id)) == NULL) {
3147: logit("%s: %d: unknown", __func__, id);
1.339 markus 3148: return 0;
1.367 djm 3149: }
1.363 markus 3150: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3151: return 0;
1.367 djm 3152: ssh_packet_check_eom(ssh);
1.275 djm 3153: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3154: return 0;
1.367 djm 3155: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3156: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 3157: explicit_bzero(cc, sizeof(*cc));
1.321 djm 3158: free(cc);
1.339 markus 3159: return 0;
1.275 djm 3160: }
1.121 markus 3161:
3162: /* -- tcp forwarding */
1.135 markus 3163:
3164: void
1.367 djm 3165: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3166: {
1.367 djm 3167: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3168: }
1.121 markus 3169:
1.312 djm 3170:
3171: /*
3172: * Determine whether or not a port forward listens to loopback, the
3173: * specified address or wildcard. On the client, a specified bind
3174: * address will always override gateway_ports. On the server, a
3175: * gateway_ports of 1 (``yes'') will override the client's specification
3176: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3177: * will bind to whatever address the client asked for.
3178: *
3179: * Special-case listen_addrs are:
3180: *
3181: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3182: * "" (empty string), "*" -> wildcard v4/v6
3183: * "localhost" -> loopback v4/v6
1.334 djm 3184: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3185: */
3186: static const char *
3187: channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
1.336 millert 3188: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3189: {
3190: const char *addr = NULL;
3191: int wildcard = 0;
3192:
3193: if (listen_addr == NULL) {
3194: /* No address specified: default to gateway_ports setting */
1.336 millert 3195: if (fwd_opts->gateway_ports)
1.312 djm 3196: wildcard = 1;
1.336 millert 3197: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 3198: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
3199: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3200: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3201: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3202: wildcard = 1;
1.326 djm 3203: /*
3204: * Notify client if they requested a specific listen
3205: * address and it was overridden.
3206: */
3207: if (*listen_addr != '\0' &&
3208: strcmp(listen_addr, "0.0.0.0") != 0 &&
3209: strcmp(listen_addr, "*") != 0) {
3210: packet_send_debug("Forwarding listen address "
3211: "\"%s\" overridden by server "
3212: "GatewayPorts", listen_addr);
3213: }
1.334 djm 3214: } else if (strcmp(listen_addr, "localhost") != 0 ||
3215: strcmp(listen_addr, "127.0.0.1") == 0 ||
3216: strcmp(listen_addr, "::1") == 0) {
3217: /* Accept localhost address when GatewayPorts=yes */
3218: addr = listen_addr;
1.326 djm 3219: }
1.334 djm 3220: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3221: strcmp(listen_addr, "::1") == 0) {
3222: /*
3223: * If a specific IPv4/IPv6 localhost address has been
3224: * requested then accept it even if gateway_ports is in
3225: * effect. This allows the client to prefer IPv4 or IPv6.
3226: */
3227: addr = listen_addr;
1.312 djm 3228: }
3229: if (wildcardp != NULL)
3230: *wildcardp = wildcard;
3231: return addr;
3232: }
3233:
1.160 markus 3234: static int
1.367 djm 3235: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3236: struct Forward *fwd, int *allocated_listen_port,
3237: struct ForwardOptions *fwd_opts)
1.25 markus 3238: {
1.113 markus 3239: Channel *c;
1.226 djm 3240: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3241: struct addrinfo hints, *ai, *aitop;
1.212 djm 3242: const char *host, *addr;
1.35 markus 3243: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3244: in_port_t *lport_p;
1.25 markus 3245:
1.212 djm 3246: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3247:
1.344 millert 3248: if (is_client && fwd->connect_path != NULL) {
3249: host = fwd->connect_path;
3250: } else {
3251: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3252: fwd->listen_host : fwd->connect_host;
3253: if (host == NULL) {
3254: error("No forward host name.");
3255: return 0;
3256: }
3257: if (strlen(host) >= NI_MAXHOST) {
3258: error("Forward host name too long.");
3259: return 0;
3260: }
1.87 markus 3261: }
1.25 markus 3262:
1.312 djm 3263: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.336 millert 3264: addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard,
3265: is_client, fwd_opts);
3266: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 3267: type, wildcard, (addr == NULL) ? "NULL" : addr);
3268:
3269: /*
1.35 markus 3270: * getaddrinfo returns a loopback address if the hostname is
3271: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3272: */
1.35 markus 3273: memset(&hints, 0, sizeof(hints));
1.367 djm 3274: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3275: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3276: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3277: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3278: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3279: if (addr == NULL) {
3280: /* This really shouldn't happen */
3281: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 3282: ssh_gai_strerror(r));
1.212 djm 3283: } else {
1.336 millert 3284: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 3285: ssh_gai_strerror(r));
1.212 djm 3286: }
1.218 markus 3287: return 0;
1.212 djm 3288: }
1.295 djm 3289: if (allocated_listen_port != NULL)
3290: *allocated_listen_port = 0;
1.35 markus 3291: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3292: switch (ai->ai_family) {
3293: case AF_INET:
3294: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3295: sin_port;
3296: break;
3297: case AF_INET6:
3298: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3299: sin6_port;
3300: break;
3301: default:
1.35 markus 3302: continue;
1.295 djm 3303: }
3304: /*
3305: * If allocating a port for -R forwards, then use the
3306: * same port for all address families.
3307: */
1.367 djm 3308: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3309: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3310: *allocated_listen_port > 0)
1.295 djm 3311: *lport_p = htons(*allocated_listen_port);
3312:
1.35 markus 3313: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3314: strport, sizeof(strport),
3315: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 3316: error("%s: getnameinfo failed", __func__);
1.35 markus 3317: continue;
3318: }
3319: /* Create a port to listen for the host. */
1.300 dtucker 3320: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 3321: if (sock < 0) {
3322: /* this is no error since kernel may not support ipv6 */
3323: verbose("socket: %.100s", strerror(errno));
3324: continue;
3325: }
1.226 djm 3326:
1.376 ! djm 3327: set_reuseaddr(sock);
1.182 stevesk 3328:
1.295 djm 3329: debug("Local forwarding listening on %s port %s.",
3330: ntop, strport);
1.35 markus 3331:
3332: /* Bind the socket to the address. */
3333: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.367 djm 3334: /*
3335: * address can be in if use ipv6 address is
3336: * already bound
3337: */
1.35 markus 3338: verbose("bind: %.100s", strerror(errno));
3339: close(sock);
3340: continue;
3341: }
3342: /* Start listening for connections on the socket. */
1.199 markus 3343: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3344: error("listen: %.100s", strerror(errno));
3345: close(sock);
3346: continue;
3347: }
1.295 djm 3348:
3349: /*
1.336 millert 3350: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3351: * record what we got.
3352: */
1.367 djm 3353: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3354: fwd->listen_port == 0 &&
1.295 djm 3355: allocated_listen_port != NULL &&
3356: *allocated_listen_port == 0) {
1.350 djm 3357: *allocated_listen_port = get_local_port(sock);
1.295 djm 3358: debug("Allocated listen port %d",
3359: *allocated_listen_port);
3360: }
3361:
1.35 markus 3362: /* Allocate a channel number for the socket. */
1.367 djm 3363: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3364: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3365: 0, "port listener", 1);
1.293 djm 3366: c->path = xstrdup(host);
1.336 millert 3367: c->host_port = fwd->connect_port;
1.312 djm 3368: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3369: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 3370: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
3371: c->listening_port = *allocated_listen_port;
3372: else
1.336 millert 3373: c->listening_port = fwd->listen_port;
1.35 markus 3374: success = 1;
3375: }
3376: if (success == 0)
1.336 millert 3377: error("%s: cannot listen to port: %d", __func__,
3378: fwd->listen_port);
1.35 markus 3379: freeaddrinfo(aitop);
1.87 markus 3380: return success;
1.25 markus 3381: }
1.1 deraadt 3382:
1.336 millert 3383: static int
1.367 djm 3384: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3385: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3386: {
3387: struct sockaddr_un sunaddr;
3388: const char *path;
3389: Channel *c;
3390: int port, sock;
3391: mode_t omask;
3392:
3393: switch (type) {
3394: case SSH_CHANNEL_UNIX_LISTENER:
3395: if (fwd->connect_path != NULL) {
3396: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3397: error("Local connecting path too long: %s",
3398: fwd->connect_path);
3399: return 0;
3400: }
3401: path = fwd->connect_path;
3402: port = PORT_STREAMLOCAL;
3403: } else {
3404: if (fwd->connect_host == NULL) {
3405: error("No forward host name.");
3406: return 0;
3407: }
3408: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3409: error("Forward host name too long.");
3410: return 0;
3411: }
3412: path = fwd->connect_host;
3413: port = fwd->connect_port;
3414: }
3415: break;
3416: case SSH_CHANNEL_RUNIX_LISTENER:
3417: path = fwd->listen_path;
3418: port = PORT_STREAMLOCAL;
3419: break;
3420: default:
3421: error("%s: unexpected channel type %d", __func__, type);
3422: return 0;
3423: }
3424:
3425: if (fwd->listen_path == NULL) {
3426: error("No forward path name.");
3427: return 0;
3428: }
3429: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3430: error("Local listening path too long: %s", fwd->listen_path);
3431: return 0;
3432: }
3433:
3434: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
3435:
3436: /* Start a Unix domain listener. */
3437: omask = umask(fwd_opts->streamlocal_bind_mask);
3438: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3439: fwd_opts->streamlocal_bind_unlink);
3440: umask(omask);
3441: if (sock < 0)
3442: return 0;
3443:
3444: debug("Local forwarding listening on path %s.", fwd->listen_path);
3445:
3446: /* Allocate a channel number for the socket. */
1.367 djm 3447: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3448: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3449: 0, "unix listener", 1);
3450: c->path = xstrdup(path);
3451: c->host_port = port;
3452: c->listening_port = PORT_STREAMLOCAL;
3453: c->listening_addr = xstrdup(fwd->listen_path);
3454: return 1;
3455: }
3456:
3457: static int
1.367 djm 3458: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3459: const char *host, u_short port)
1.202 djm 3460: {
1.209 avsm 3461: u_int i;
3462: int found = 0;
1.202 djm 3463:
1.367 djm 3464: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3465: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3466: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3467: continue;
3468: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3469: debug2("%s: close channel %d", __func__, i);
1.367 djm 3470: channel_free(ssh, c);
1.312 djm 3471: found = 1;
3472: }
3473: }
3474:
1.367 djm 3475: return found;
1.312 djm 3476: }
3477:
1.336 millert 3478: static int
1.367 djm 3479: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3480: {
3481: u_int i;
3482: int found = 0;
3483:
1.367 djm 3484: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3485: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3486: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3487: continue;
3488: if (c->path == NULL)
3489: continue;
3490: if (strcmp(c->path, path) == 0) {
3491: debug2("%s: close channel %d", __func__, i);
1.367 djm 3492: channel_free(ssh, c);
1.336 millert 3493: found = 1;
3494: }
3495: }
3496:
1.367 djm 3497: return found;
1.336 millert 3498: }
3499:
1.312 djm 3500: int
1.367 djm 3501: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3502: {
1.367 djm 3503: if (fwd->listen_path != NULL) {
3504: return channel_cancel_rport_listener_streamlocal(ssh,
3505: fwd->listen_path);
3506: } else {
3507: return channel_cancel_rport_listener_tcpip(ssh,
3508: fwd->listen_host, fwd->listen_port);
3509: }
1.336 millert 3510: }
3511:
3512: static int
1.367 djm 3513: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3514: const char *lhost, u_short lport, int cport,
3515: struct ForwardOptions *fwd_opts)
1.312 djm 3516: {
3517: u_int i;
3518: int found = 0;
1.336 millert 3519: const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts);
1.202 djm 3520:
1.367 djm 3521: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3522: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3523: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3524: continue;
1.313 markus 3525: if (c->listening_port != lport)
1.312 djm 3526: continue;
1.313 markus 3527: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3528: /* skip dynamic forwardings */
3529: if (c->host_port == 0)
3530: continue;
3531: } else {
3532: if (c->host_port != cport)
3533: continue;
3534: }
1.312 djm 3535: if ((c->listening_addr == NULL && addr != NULL) ||
3536: (c->listening_addr != NULL && addr == NULL))
3537: continue;
3538: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3539: debug2("%s: close channel %d", __func__, i);
1.367 djm 3540: channel_free(ssh, c);
1.202 djm 3541: found = 1;
3542: }
3543: }
3544:
1.367 djm 3545: return found;
1.202 djm 3546: }
3547:
1.336 millert 3548: static int
1.367 djm 3549: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3550: {
3551: u_int i;
3552: int found = 0;
3553:
3554: if (path == NULL) {
3555: error("%s: no path specified.", __func__);
3556: return 0;
3557: }
3558:
1.367 djm 3559: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3560: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3561: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3562: continue;
3563: if (c->listening_addr == NULL)
3564: continue;
3565: if (strcmp(c->listening_addr, path) == 0) {
3566: debug2("%s: close channel %d", __func__, i);
1.367 djm 3567: channel_free(ssh, c);
1.336 millert 3568: found = 1;
3569: }
3570: }
3571:
1.367 djm 3572: return found;
1.336 millert 3573: }
3574:
3575: int
1.367 djm 3576: channel_cancel_lport_listener(struct ssh *ssh,
3577: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3578: {
1.367 djm 3579: if (fwd->listen_path != NULL) {
3580: return channel_cancel_lport_listener_streamlocal(ssh,
3581: fwd->listen_path);
3582: } else {
3583: return channel_cancel_lport_listener_tcpip(ssh,
3584: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3585: }
1.336 millert 3586: }
3587:
1.362 markus 3588: /* protocol local port fwd, used by ssh */
1.160 markus 3589: int
1.367 djm 3590: channel_setup_local_fwd_listener(struct ssh *ssh,
3591: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3592: {
1.336 millert 3593: if (fwd->listen_path != NULL) {
1.367 djm 3594: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3595: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3596: } else {
1.367 djm 3597: return channel_setup_fwd_listener_tcpip(ssh,
3598: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3599: }
1.160 markus 3600: }
3601:
3602: /* protocol v2 remote port fwd, used by sshd */
3603: int
1.367 djm 3604: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3605: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3606: {
1.336 millert 3607: if (fwd->listen_path != NULL) {
1.367 djm 3608: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3609: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3610: } else {
1.367 djm 3611: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 3612: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3613: fwd_opts);
3614: }
1.160 markus 3615: }
3616:
1.27 markus 3617: /*
1.312 djm 3618: * Translate the requested rfwd listen host to something usable for
3619: * this server.
3620: */
3621: static const char *
3622: channel_rfwd_bind_host(const char *listen_host)
3623: {
3624: if (listen_host == NULL) {
3625: if (datafellows & SSH_BUG_RFWD_ADDR)
3626: return "127.0.0.1";
3627: else
3628: return "localhost";
3629: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
3630: if (datafellows & SSH_BUG_RFWD_ADDR)
3631: return "0.0.0.0";
3632: else
3633: return "";
3634: } else
3635: return listen_host;
3636: }
3637:
3638: /*
1.27 markus 3639: * Initiate forwarding of connections to port "port" on remote host through
3640: * the secure channel to host:port from local side.
1.315 markus 3641: * Returns handle (index) for updating the dynamic listen port with
3642: * channel_update_permitted_opens().
1.27 markus 3643: */
1.253 markus 3644: int
1.367 djm 3645: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 3646: {
1.367 djm 3647: int r, success = 0, idx = -1;
3648: char *host_to_connect, *listen_host, *listen_path;
3649: int port_to_connect, listen_port;
1.73 markus 3650:
1.25 markus 3651: /* Send the forward request to the remote side. */
1.358 djm 3652: if (fwd->listen_path != NULL) {
1.367 djm 3653: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3654: (r = sshpkt_put_cstring(ssh,
3655: "streamlocal-forward@openssh.com")) != 0 ||
3656: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3657: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3658: (r = sshpkt_send(ssh)) != 0 ||
3659: (r = ssh_packet_write_wait(ssh)) != 0)
3660: fatal("%s: request streamlocal: %s",
3661: __func__, ssh_err(r));
1.336 millert 3662: } else {
1.367 djm 3663: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3664: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
3665: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3666: (r = sshpkt_put_cstring(ssh,
3667: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
3668: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
3669: (r = sshpkt_send(ssh)) != 0 ||
3670: (r = ssh_packet_write_wait(ssh)) != 0)
3671: fatal("%s: request tcpip-forward: %s",
3672: __func__, ssh_err(r));
1.73 markus 3673: }
1.358 djm 3674: /* Assume that server accepts the request */
3675: success = 1;
1.73 markus 3676: if (success) {
1.305 djm 3677: /* Record that connection to this host/port is permitted. */
1.367 djm 3678: host_to_connect = listen_host = listen_path = NULL;
3679: port_to_connect = listen_port = 0;
1.336 millert 3680: if (fwd->connect_path != NULL) {
1.367 djm 3681: host_to_connect = xstrdup(fwd->connect_path);
3682: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 3683: } else {
1.367 djm 3684: host_to_connect = xstrdup(fwd->connect_host);
3685: port_to_connect = fwd->connect_port;
1.336 millert 3686: }
3687: if (fwd->listen_path != NULL) {
1.367 djm 3688: listen_path = xstrdup(fwd->listen_path);
3689: listen_port = PORT_STREAMLOCAL;
1.336 millert 3690: } else {
1.367 djm 3691: if (fwd->listen_host != NULL)
3692: listen_host = xstrdup(fwd->listen_host);
3693: listen_port = fwd->listen_port;
3694: }
3695: idx = fwd_perm_list_add(ssh, FWDPERM_USER,
3696: host_to_connect, port_to_connect,
3697: listen_host, listen_path, listen_port, NULL);
1.44 markus 3698: }
1.367 djm 3699: return idx;
1.1 deraadt 3700: }
3701:
1.333 markus 3702: static int
3703: open_match(ForwardPermission *allowed_open, const char *requestedhost,
1.336 millert 3704: int requestedport)
1.333 markus 3705: {
3706: if (allowed_open->host_to_connect == NULL)
3707: return 0;
3708: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3709: allowed_open->port_to_connect != requestedport)
3710: return 0;
1.351 dtucker 3711: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3712: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3713: return 0;
3714: return 1;
3715: }
3716:
3717: /*
1.336 millert 3718: * Note that in the listen host/port case
1.333 markus 3719: * we don't support FWD_PERMIT_ANY_PORT and
3720: * need to translate between the configured-host (listen_host)
3721: * and what we've sent to the remote server (channel_rfwd_bind_host)
3722: */
3723: static int
1.336 millert 3724: open_listen_match_tcpip(ForwardPermission *allowed_open,
3725: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3726: {
3727: const char *allowed_host;
3728:
3729: if (allowed_open->host_to_connect == NULL)
3730: return 0;
3731: if (allowed_open->listen_port != requestedport)
3732: return 0;
1.335 djm 3733: if (!translate && allowed_open->listen_host == NULL &&
3734: requestedhost == NULL)
3735: return 1;
1.333 markus 3736: allowed_host = translate ?
3737: channel_rfwd_bind_host(allowed_open->listen_host) :
3738: allowed_open->listen_host;
3739: if (allowed_host == NULL ||
3740: strcmp(allowed_host, requestedhost) != 0)
3741: return 0;
3742: return 1;
3743: }
3744:
1.336 millert 3745: static int
3746: open_listen_match_streamlocal(ForwardPermission *allowed_open,
3747: const char *requestedpath)
3748: {
3749: if (allowed_open->host_to_connect == NULL)
3750: return 0;
3751: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3752: return 0;
3753: if (allowed_open->listen_path == NULL ||
3754: strcmp(allowed_open->listen_path, requestedpath) != 0)
3755: return 0;
3756: return 1;
3757: }
3758:
1.27 markus 3759: /*
1.208 deraadt 3760: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3761: * local side.
3762: */
1.336 millert 3763: static int
1.367 djm 3764: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
3765: const char *host, u_short port)
1.202 djm 3766: {
1.367 djm 3767: struct ssh_channels *sc = ssh->chanctxt;
3768: int r;
3769: u_int i;
3770: ForwardPermission *fp;
1.202 djm 3771:
1.367 djm 3772: for (i = 0; i < sc->num_permitted_opens; i++) {
3773: fp = &sc->permitted_opens[i];
3774: if (open_listen_match_tcpip(fp, host, port, 0))
1.202 djm 3775: break;
1.367 djm 3776: fp = NULL;
1.202 djm 3777: }
1.367 djm 3778: if (fp == NULL) {
1.202 djm 3779: debug("%s: requested forward not found", __func__);
1.312 djm 3780: return -1;
1.202 djm 3781: }
1.367 djm 3782: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3783: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
3784: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3785: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
3786: (r = sshpkt_put_u32(ssh, port)) != 0 ||
3787: (r = sshpkt_send(ssh)) != 0)
3788: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3789:
3790: fwd_perm_clear(fp); /* unregister */
1.336 millert 3791:
3792: return 0;
3793: }
3794:
3795: /*
3796: * Request cancellation of remote forwarding of Unix domain socket
3797: * path from local side.
3798: */
3799: static int
1.367 djm 3800: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3801: {
1.367 djm 3802: struct ssh_channels *sc = ssh->chanctxt;
3803: int r;
3804: u_int i;
3805: ForwardPermission *fp;
1.336 millert 3806:
1.367 djm 3807: for (i = 0; i < sc->num_permitted_opens; i++) {
3808: fp = &sc->permitted_opens[i];
3809: if (open_listen_match_streamlocal(fp, path))
1.336 millert 3810: break;
1.367 djm 3811: fp = NULL;
1.336 millert 3812: }
1.367 djm 3813: if (fp == NULL) {
1.336 millert 3814: debug("%s: requested forward not found", __func__);
3815: return -1;
3816: }
1.367 djm 3817: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3818: (r = sshpkt_put_cstring(ssh,
3819: "cancel-streamlocal-forward@openssh.com")) != 0 ||
3820: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3821: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
3822: (r = sshpkt_send(ssh)) != 0)
3823: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3824:
3825: fwd_perm_clear(fp); /* unregister */
1.312 djm 3826:
3827: return 0;
1.202 djm 3828: }
3829:
3830: /*
1.336 millert 3831: * Request cancellation of remote forwarding of a connection from local side.
3832: */
3833: int
1.367 djm 3834: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3835: {
3836: if (fwd->listen_path != NULL) {
1.367 djm 3837: return channel_request_rforward_cancel_streamlocal(ssh,
3838: fwd->listen_path);
1.336 millert 3839: } else {
1.367 djm 3840: return channel_request_rforward_cancel_tcpip(ssh,
3841: fwd->listen_host,
3842: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 3843: }
1.1 deraadt 3844: }
3845:
1.99 markus 3846: /*
3847: * Permits opening to any host/port if permitted_opens[] is empty. This is
3848: * usually called by the server, because the user could connect to any port
3849: * anyway, and the server has no way to know but to trust the client anyway.
3850: */
3851: void
1.367 djm 3852: channel_permit_all_opens(struct ssh *ssh)
1.99 markus 3853: {
1.367 djm 3854: if (ssh->chanctxt->num_permitted_opens == 0)
3855: ssh->chanctxt->all_opens_permitted = 1;
1.99 markus 3856: }
3857:
1.101 markus 3858: void
1.367 djm 3859: channel_add_permitted_opens(struct ssh *ssh, char *host, int port)
1.99 markus 3860: {
1.367 djm 3861: struct ssh_channels *sc = ssh->chanctxt;
3862:
1.99 markus 3863: debug("allow port forwarding to host %s port %d", host, port);
1.367 djm 3864: fwd_perm_list_add(ssh, FWDPERM_USER, host, port, NULL, NULL, 0, NULL);
3865: sc->all_opens_permitted = 0;
1.315 markus 3866: }
3867:
3868: /*
3869: * Update the listen port for a dynamic remote forward, after
3870: * the actual 'newport' has been allocated. If 'newport' < 0 is
3871: * passed then they entry will be invalidated.
3872: */
3873: void
1.367 djm 3874: channel_update_permitted_opens(struct ssh *ssh, int idx, int newport)
1.315 markus 3875: {
1.367 djm 3876: struct ssh_channels *sc = ssh->chanctxt;
3877:
3878: if (idx < 0 || (u_int)idx >= sc->num_permitted_opens) {
3879: debug("%s: index out of range: %d num_permitted_opens %d",
3880: __func__, idx, sc->num_permitted_opens);
1.315 markus 3881: return;
3882: }
3883: debug("%s allowed port %d for forwarding to host %s port %d",
3884: newport > 0 ? "Updating" : "Removing",
3885: newport,
1.367 djm 3886: sc->permitted_opens[idx].host_to_connect,
3887: sc->permitted_opens[idx].port_to_connect);
3888: if (newport <= 0)
3889: fwd_perm_clear(&sc->permitted_opens[idx]);
3890: else {
3891: sc->permitted_opens[idx].listen_port =
1.315 markus 3892: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
3893: }
1.99 markus 3894: }
3895:
1.258 dtucker 3896: int
1.367 djm 3897: channel_add_adm_permitted_opens(struct ssh *ssh, char *host, int port)
1.257 dtucker 3898: {
1.258 dtucker 3899: debug("config allows port forwarding to host %s port %d", host, port);
1.367 djm 3900: return fwd_perm_list_add(ssh, FWDPERM_ADMIN, host, port,
3901: NULL, NULL, 0, NULL);
1.316 dtucker 3902: }
3903:
3904: void
1.367 djm 3905: channel_disable_adm_local_opens(struct ssh *ssh)
1.99 markus 3906: {
1.367 djm 3907: channel_clear_adm_permitted_opens(ssh);
3908: fwd_perm_list_add(ssh, FWDPERM_ADMIN, NULL, 0, NULL, NULL, 0, NULL);
1.257 dtucker 3909: }
3910:
3911: void
1.367 djm 3912: channel_clear_permitted_opens(struct ssh *ssh)
1.257 dtucker 3913: {
1.367 djm 3914: struct ssh_channels *sc = ssh->chanctxt;
1.99 markus 3915:
1.367 djm 3916: sc->permitted_opens = xrecallocarray(sc->permitted_opens,
3917: sc->num_permitted_opens, 0, sizeof(*sc->permitted_opens));
3918: sc->num_permitted_opens = 0;
1.278 dtucker 3919: }
3920:
3921: void
1.367 djm 3922: channel_clear_adm_permitted_opens(struct ssh *ssh)
1.278 dtucker 3923: {
1.367 djm 3924: struct ssh_channels *sc = ssh->chanctxt;
1.278 dtucker 3925:
1.367 djm 3926: sc->permitted_adm_opens = xrecallocarray(sc->permitted_adm_opens,
3927: sc->num_adm_permitted_opens, 0, sizeof(*sc->permitted_adm_opens));
3928: sc->num_adm_permitted_opens = 0;
1.99 markus 3929: }
3930:
1.314 dtucker 3931: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3932: int
3933: permitopen_port(const char *p)
3934: {
3935: int port;
3936:
3937: if (strcmp(p, "*") == 0)
3938: return FWD_PERMIT_ANY_PORT;
3939: if ((port = a2port(p)) > 0)
3940: return port;
3941: return -1;
3942: }
3943:
1.276 djm 3944: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 3945: static int
1.276 djm 3946: connect_next(struct channel_connect *cctx)
1.41 markus 3947: {
1.276 djm 3948: int sock, saved_errno;
1.336 millert 3949: struct sockaddr_un *sunaddr;
1.367 djm 3950: char ntop[NI_MAXHOST];
3951: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 3952:
1.276 djm 3953: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 3954: switch (cctx->ai->ai_family) {
3955: case AF_UNIX:
3956: /* unix:pathname instead of host:port */
3957: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
3958: strlcpy(ntop, "unix", sizeof(ntop));
3959: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
3960: break;
3961: case AF_INET:
3962: case AF_INET6:
3963: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
3964: ntop, sizeof(ntop), strport, sizeof(strport),
3965: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
3966: error("connect_next: getnameinfo failed");
3967: continue;
3968: }
3969: break;
3970: default:
1.41 markus 3971: continue;
3972: }
1.300 dtucker 3973: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
3974: cctx->ai->ai_protocol)) == -1) {
1.276 djm 3975: if (cctx->ai->ai_next == NULL)
1.186 djm 3976: error("socket: %.100s", strerror(errno));
3977: else
3978: verbose("socket: %.100s", strerror(errno));
1.41 markus 3979: continue;
3980: }
1.205 djm 3981: if (set_nonblock(sock) == -1)
3982: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 3983: if (connect(sock, cctx->ai->ai_addr,
3984: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
3985: debug("connect_next: host %.100s ([%.100s]:%s): "
3986: "%.100s", cctx->host, ntop, strport,
1.41 markus 3987: strerror(errno));
1.276 djm 3988: saved_errno = errno;
1.41 markus 3989: close(sock);
1.276 djm 3990: errno = saved_errno;
1.89 stevesk 3991: continue; /* fail -- try next */
1.41 markus 3992: }
1.336 millert 3993: if (cctx->ai->ai_family != AF_UNIX)
3994: set_nodelay(sock);
1.276 djm 3995: debug("connect_next: host %.100s ([%.100s]:%s) "
3996: "in progress, fd=%d", cctx->host, ntop, strport, sock);
3997: cctx->ai = cctx->ai->ai_next;
3998: return sock;
3999: }
4000: return -1;
4001: }
1.41 markus 4002:
1.276 djm 4003: static void
4004: channel_connect_ctx_free(struct channel_connect *cctx)
4005: {
1.321 djm 4006: free(cctx->host);
1.336 millert 4007: if (cctx->aitop) {
4008: if (cctx->aitop->ai_family == AF_UNIX)
4009: free(cctx->aitop);
4010: else
4011: freeaddrinfo(cctx->aitop);
4012: }
1.329 tedu 4013: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4014: }
4015:
1.357 dtucker 4016: /*
1.372 markus 4017: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4018: * passing back the failure reason if appropriate.
4019: */
1.372 markus 4020: static int
4021: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4022: char *ctype, char *rname, struct channel_connect *cctx,
4023: int *reason, const char **errmsg)
1.276 djm 4024: {
4025: struct addrinfo hints;
4026: int gaierr;
4027: int sock = -1;
4028: char strport[NI_MAXSERV];
1.336 millert 4029:
4030: if (port == PORT_STREAMLOCAL) {
4031: struct sockaddr_un *sunaddr;
4032: struct addrinfo *ai;
4033:
4034: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4035: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4036: return -1;
1.336 millert 4037: }
4038:
4039: /*
4040: * Fake up a struct addrinfo for AF_UNIX connections.
4041: * channel_connect_ctx_free() must check ai_family
4042: * and use free() not freeaddirinfo() for AF_UNIX.
4043: */
4044: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4045: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4046: ai->ai_addr = (struct sockaddr *)(ai + 1);
4047: ai->ai_addrlen = sizeof(*sunaddr);
4048: ai->ai_family = AF_UNIX;
1.372 markus 4049: ai->ai_socktype = socktype;
1.336 millert 4050: ai->ai_protocol = PF_UNSPEC;
4051: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4052: sunaddr->sun_family = AF_UNIX;
4053: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4054: cctx->aitop = ai;
1.336 millert 4055: } else {
4056: memset(&hints, 0, sizeof(hints));
1.367 djm 4057: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4058: hints.ai_socktype = socktype;
1.336 millert 4059: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4060: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4061: != 0) {
4062: if (errmsg != NULL)
4063: *errmsg = ssh_gai_strerror(gaierr);
4064: if (reason != NULL)
4065: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4066: error("connect_to %.100s: unknown host (%s)", name,
4067: ssh_gai_strerror(gaierr));
1.372 markus 4068: return -1;
1.336 millert 4069: }
1.41 markus 4070: }
1.276 djm 4071:
1.372 markus 4072: cctx->host = xstrdup(name);
4073: cctx->port = port;
4074: cctx->ai = cctx->aitop;
1.276 djm 4075:
1.372 markus 4076: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4077: error("connect to %.100s port %d failed: %s",
1.336 millert 4078: name, port, strerror(errno));
1.372 markus 4079: return -1;
4080: }
4081:
4082: return sock;
4083: }
4084:
4085: /* Return CONNECTING channel to remote host:port or local socket path */
4086: static Channel *
4087: connect_to(struct ssh *ssh, const char *host, int port,
4088: char *ctype, char *rname)
4089: {
4090: struct channel_connect cctx;
4091: Channel *c;
4092: int sock;
4093:
4094: memset(&cctx, 0, sizeof(cctx));
4095: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4096: &cctx, NULL, NULL);
4097: if (sock == -1) {
1.276 djm 4098: channel_connect_ctx_free(&cctx);
4099: return NULL;
1.41 markus 4100: }
1.367 djm 4101: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4102: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4103: c->host_port = port;
4104: c->path = xstrdup(host);
1.276 djm 4105: c->connect_ctx = cctx;
1.372 markus 4106:
1.276 djm 4107: return c;
1.41 markus 4108: }
1.99 markus 4109:
1.354 markus 4110: /*
4111: * returns either the newly connected channel or the downstream channel
4112: * that needs to deal with this connection.
4113: */
1.276 djm 4114: Channel *
1.367 djm 4115: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4116: u_short listen_port, char *ctype, char *rname)
1.73 markus 4117: {
1.367 djm 4118: struct ssh_channels *sc = ssh->chanctxt;
4119: u_int i;
4120: ForwardPermission *fp;
1.99 markus 4121:
1.367 djm 4122: for (i = 0; i < sc->num_permitted_opens; i++) {
4123: fp = &sc->permitted_opens[i];
4124: if (open_listen_match_tcpip(fp, listen_host, listen_port, 1)) {
4125: if (fp->downstream)
4126: return fp->downstream;
1.372 markus 4127: if (fp->port_to_connect == 0)
4128: return rdynamic_connect_prepare(ssh,
4129: ctype, rname);
1.367 djm 4130: return connect_to(ssh,
4131: fp->host_to_connect, fp->port_to_connect,
4132: ctype, rname);
1.276 djm 4133: }
4134: }
1.74 markus 4135: error("WARNING: Server requests forwarding for unknown listen_port %d",
4136: listen_port);
1.276 djm 4137: return NULL;
1.73 markus 4138: }
4139:
1.336 millert 4140: Channel *
1.367 djm 4141: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4142: char *ctype, char *rname)
1.336 millert 4143: {
1.367 djm 4144: struct ssh_channels *sc = ssh->chanctxt;
4145: u_int i;
4146: ForwardPermission *fp;
1.336 millert 4147:
1.367 djm 4148: for (i = 0; i < sc->num_permitted_opens; i++) {
4149: fp = &sc->permitted_opens[i];
4150: if (open_listen_match_streamlocal(fp, path)) {
4151: return connect_to(ssh,
4152: fp->host_to_connect, fp->port_to_connect,
4153: ctype, rname);
1.336 millert 4154: }
4155: }
4156: error("WARNING: Server requests forwarding for unknown path %.100s",
4157: path);
4158: return NULL;
4159: }
4160:
1.99 markus 4161: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4162: Channel *
1.367 djm 4163: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4164: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4165: {
1.367 djm 4166: struct ssh_channels *sc = ssh->chanctxt;
1.372 markus 4167: struct channel_connect cctx;
4168: Channel *c;
1.367 djm 4169: u_int i, permit, permit_adm = 1;
1.372 markus 4170: int sock;
1.367 djm 4171: ForwardPermission *fp;
1.99 markus 4172:
1.367 djm 4173: permit = sc->all_opens_permitted;
1.99 markus 4174: if (!permit) {
1.367 djm 4175: for (i = 0; i < sc->num_permitted_opens; i++) {
4176: fp = &sc->permitted_opens[i];
4177: if (open_match(fp, host, port)) {
1.99 markus 4178: permit = 1;
1.333 markus 4179: break;
4180: }
1.367 djm 4181: }
1.257 dtucker 4182: }
1.99 markus 4183:
1.367 djm 4184: if (sc->num_adm_permitted_opens > 0) {
1.257 dtucker 4185: permit_adm = 0;
1.367 djm 4186: for (i = 0; i < sc->num_adm_permitted_opens; i++) {
4187: fp = &sc->permitted_adm_opens[i];
4188: if (open_match(fp, host, port)) {
1.257 dtucker 4189: permit_adm = 1;
1.333 markus 4190: break;
4191: }
1.367 djm 4192: }
1.99 markus 4193: }
1.257 dtucker 4194:
4195: if (!permit || !permit_adm) {
1.188 itojun 4196: logit("Received request to connect to host %.100s port %d, "
1.99 markus 4197: "but the request was denied.", host, port);
1.357 dtucker 4198: if (reason != NULL)
4199: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4200: return NULL;
1.99 markus 4201: }
1.372 markus 4202:
4203: memset(&cctx, 0, sizeof(cctx));
4204: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4205: &cctx, reason, errmsg);
4206: if (sock == -1) {
4207: channel_connect_ctx_free(&cctx);
4208: return NULL;
4209: }
4210:
4211: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4212: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4213: c->host_port = port;
4214: c->path = xstrdup(host);
4215: c->connect_ctx = cctx;
4216:
4217: return c;
1.336 millert 4218: }
4219:
4220: /* Check if connecting to that path is permitted and connect. */
4221: Channel *
1.367 djm 4222: channel_connect_to_path(struct ssh *ssh, const char *path,
4223: char *ctype, char *rname)
1.336 millert 4224: {
1.367 djm 4225: struct ssh_channels *sc = ssh->chanctxt;
4226: u_int i, permit, permit_adm = 1;
4227: ForwardPermission *fp;
1.336 millert 4228:
1.367 djm 4229: permit = sc->all_opens_permitted;
1.336 millert 4230: if (!permit) {
1.367 djm 4231: for (i = 0; i < sc->num_permitted_opens; i++) {
4232: fp = &sc->permitted_opens[i];
4233: if (open_match(fp, path, PORT_STREAMLOCAL)) {
1.336 millert 4234: permit = 1;
4235: break;
4236: }
1.367 djm 4237: }
1.336 millert 4238: }
4239:
1.367 djm 4240: if (sc->num_adm_permitted_opens > 0) {
1.336 millert 4241: permit_adm = 0;
1.367 djm 4242: for (i = 0; i < sc->num_adm_permitted_opens; i++) {
4243: fp = &sc->permitted_adm_opens[i];
4244: if (open_match(fp, path, PORT_STREAMLOCAL)) {
1.336 millert 4245: permit_adm = 1;
4246: break;
4247: }
1.367 djm 4248: }
1.336 millert 4249: }
4250:
4251: if (!permit || !permit_adm) {
4252: logit("Received request to connect to path %.100s, "
4253: "but the request was denied.", path);
4254: return NULL;
4255: }
1.367 djm 4256: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4257: }
4258:
4259: void
1.367 djm 4260: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4261: {
1.367 djm 4262: struct ssh_channels *sc = ssh->chanctxt;
4263: struct winsize ws;
4264: int r;
1.209 avsm 4265: u_int i;
1.204 djm 4266:
1.367 djm 4267: for (i = 0; i < sc->channels_alloc; i++) {
4268: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4269: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4270: continue;
1.367 djm 4271: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
1.204 djm 4272: continue;
1.367 djm 4273: channel_request_start(ssh, i, "window-change", 0);
4274: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4275: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4276: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4277: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4278: (r = sshpkt_send(ssh)) != 0)
4279: fatal("%s: channel %u: send window-change: %s",
4280: __func__, i, ssh_err(r));
1.204 djm 4281: }
1.372 markus 4282: }
4283:
4284: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4285: static Channel *
4286: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4287: {
4288: Channel *c;
4289: int r;
4290:
4291: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4292: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4293: c->host_port = 0;
4294: c->path = NULL;
4295:
4296: /*
4297: * We need to open the channel before we have a FD,
4298: * so that we can get SOCKS header from peer.
4299: */
4300: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4301: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4302: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4303: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
4304: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
4305: fatal("%s: channel %i: confirm: %s", __func__,
4306: c->self, ssh_err(r));
4307: }
4308: return c;
4309: }
4310:
4311: /* Return CONNECTING socket to remote host:port or local socket path */
4312: static int
4313: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4314: {
4315: struct channel_connect cctx;
4316: int sock;
4317:
4318: memset(&cctx, 0, sizeof(cctx));
4319: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4320: NULL, &cctx, NULL, NULL);
4321: if (sock == -1)
4322: channel_connect_ctx_free(&cctx);
4323: else {
4324: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4325: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4326: c->connect_ctx = cctx;
4327: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4328: }
4329: return sock;
1.99 markus 4330: }
4331:
1.121 markus 4332: /* -- X11 forwarding */
1.1 deraadt 4333:
1.27 markus 4334: /*
4335: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4336: * Returns 0 and a suitable display number for the DISPLAY variable
4337: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4338: */
1.141 stevesk 4339: int
1.367 djm 4340: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4341: int x11_use_localhost, int single_connection,
4342: u_int *display_numberp, int **chanids)
1.1 deraadt 4343: {
1.149 markus 4344: Channel *nc = NULL;
1.31 markus 4345: int display_number, sock;
4346: u_short port;
1.35 markus 4347: struct addrinfo hints, *ai, *aitop;
4348: char strport[NI_MAXSERV];
4349: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4350:
1.224 markus 4351: if (chanids == NULL)
4352: return -1;
4353:
1.33 markus 4354: for (display_number = x11_display_offset;
1.148 deraadt 4355: display_number < MAX_DISPLAYS;
4356: display_number++) {
1.25 markus 4357: port = 6000 + display_number;
1.35 markus 4358: memset(&hints, 0, sizeof(hints));
1.367 djm 4359: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4360: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4361: hints.ai_socktype = SOCK_STREAM;
4362: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4363: if ((gaierr = getaddrinfo(NULL, strport,
4364: &hints, &aitop)) != 0) {
1.271 dtucker 4365: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4366: return -1;
1.25 markus 4367: }
1.35 markus 4368: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4369: if (ai->ai_family != AF_INET &&
4370: ai->ai_family != AF_INET6)
1.35 markus 4371: continue;
1.300 dtucker 4372: sock = socket(ai->ai_family, ai->ai_socktype,
4373: ai->ai_protocol);
1.35 markus 4374: if (sock < 0) {
4375: error("socket: %.100s", strerror(errno));
1.203 markus 4376: freeaddrinfo(aitop);
1.141 stevesk 4377: return -1;
1.35 markus 4378: }
1.376 ! djm 4379: set_reuseaddr(sock);
1.35 markus 4380: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.367 djm 4381: debug2("%s: bind port %d: %.100s", __func__,
4382: port, strerror(errno));
1.35 markus 4383: close(sock);
1.367 djm 4384: for (n = 0; n < num_socks; n++)
1.35 markus 4385: close(socks[n]);
4386: num_socks = 0;
4387: break;
4388: }
4389: socks[num_socks++] = sock;
4390: if (num_socks == NUM_SOCKS)
4391: break;
1.25 markus 4392: }
1.83 stevesk 4393: freeaddrinfo(aitop);
1.35 markus 4394: if (num_socks > 0)
4395: break;
1.25 markus 4396: }
4397: if (display_number >= MAX_DISPLAYS) {
4398: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4399: return -1;
1.25 markus 4400: }
4401: /* Start listening for connections on the socket. */
1.35 markus 4402: for (n = 0; n < num_socks; n++) {
4403: sock = socks[n];
1.199 markus 4404: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 4405: error("listen: %.100s", strerror(errno));
4406: close(sock);
1.141 stevesk 4407: return -1;
1.35 markus 4408: }
1.25 markus 4409: }
1.35 markus 4410:
4411: /* Allocate a channel for each socket. */
1.242 djm 4412: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4413: for (n = 0; n < num_socks; n++) {
4414: sock = socks[n];
1.367 djm 4415: nc = channel_new(ssh, "x11 listener",
1.51 markus 4416: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4417: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4418: 0, "X11 inet listener", 1);
1.167 markus 4419: nc->single_connection = single_connection;
1.224 markus 4420: (*chanids)[n] = nc->self;
1.35 markus 4421: }
1.224 markus 4422: (*chanids)[n] = -1;
1.1 deraadt 4423:
1.141 stevesk 4424: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4425: *display_numberp = display_number;
1.367 djm 4426: return 0;
1.1 deraadt 4427: }
4428:
1.127 itojun 4429: static int
1.77 markus 4430: connect_local_xsocket(u_int dnr)
1.1 deraadt 4431: {
1.25 markus 4432: int sock;
4433: struct sockaddr_un addr;
4434:
1.147 stevesk 4435: sock = socket(AF_UNIX, SOCK_STREAM, 0);
4436: if (sock < 0)
4437: error("socket: %.100s", strerror(errno));
4438: memset(&addr, 0, sizeof(addr));
4439: addr.sun_family = AF_UNIX;
4440: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4441: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4442: return sock;
4443: close(sock);
1.25 markus 4444: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4445: return -1;
1.1 deraadt 4446: }
4447:
1.51 markus 4448: int
1.367 djm 4449: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4450: {
1.248 deraadt 4451: u_int display_number;
1.25 markus 4452: const char *display;
1.51 markus 4453: char buf[1024], *cp;
1.35 markus 4454: struct addrinfo hints, *ai, *aitop;
4455: char strport[NI_MAXSERV];
1.248 deraadt 4456: int gaierr, sock = 0;
1.25 markus 4457:
4458: /* Try to open a socket for the local X server. */
4459: display = getenv("DISPLAY");
4460: if (!display) {
4461: error("DISPLAY not set.");
1.51 markus 4462: return -1;
1.25 markus 4463: }
1.27 markus 4464: /*
4465: * Now we decode the value of the DISPLAY variable and make a
4466: * connection to the real X server.
4467: */
4468:
4469: /*
4470: * Check if it is a unix domain socket. Unix domain displays are in
4471: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4472: */
1.25 markus 4473: if (strncmp(display, "unix:", 5) == 0 ||
4474: display[0] == ':') {
4475: /* Connect to the unix domain socket. */
1.367 djm 4476: if (sscanf(strrchr(display, ':') + 1, "%u",
4477: &display_number) != 1) {
4478: error("Could not parse display number from DISPLAY: "
4479: "%.100s", display);
1.51 markus 4480: return -1;
1.25 markus 4481: }
4482: /* Create a socket. */
4483: sock = connect_local_xsocket(display_number);
4484: if (sock < 0)
1.51 markus 4485: return -1;
1.25 markus 4486:
4487: /* OK, we now have a connection to the display. */
1.51 markus 4488: return sock;
1.25 markus 4489: }
1.27 markus 4490: /*
4491: * Connect to an inet socket. The DISPLAY value is supposedly
4492: * hostname:d[.s], where hostname may also be numeric IP address.
4493: */
1.145 stevesk 4494: strlcpy(buf, display, sizeof(buf));
1.25 markus 4495: cp = strchr(buf, ':');
4496: if (!cp) {
4497: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4498: return -1;
1.25 markus 4499: }
4500: *cp = 0;
1.367 djm 4501: /*
4502: * buf now contains the host name. But first we parse the
4503: * display number.
4504: */
1.248 deraadt 4505: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4506: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4507: display);
1.51 markus 4508: return -1;
1.25 markus 4509: }
1.35 markus 4510:
4511: /* Look up the host address */
4512: memset(&hints, 0, sizeof(hints));
1.367 djm 4513: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4514: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4515: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4516: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4517: error("%.100s: unknown host. (%s)", buf,
4518: ssh_gai_strerror(gaierr));
1.51 markus 4519: return -1;
1.25 markus 4520: }
1.35 markus 4521: for (ai = aitop; ai; ai = ai->ai_next) {
4522: /* Create a socket. */
1.300 dtucker 4523: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 4524: if (sock < 0) {
1.194 markus 4525: debug2("socket: %.100s", strerror(errno));
1.41 markus 4526: continue;
4527: }
4528: /* Connect it to the display. */
4529: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 4530: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4531: 6000 + display_number, strerror(errno));
4532: close(sock);
4533: continue;
4534: }
4535: /* Success */
4536: break;
1.35 markus 4537: }
4538: freeaddrinfo(aitop);
4539: if (!ai) {
1.367 djm 4540: error("connect %.100s port %u: %.100s", buf,
4541: 6000 + display_number, strerror(errno));
1.51 markus 4542: return -1;
1.25 markus 4543: }
1.162 stevesk 4544: set_nodelay(sock);
1.51 markus 4545: return sock;
4546: }
4547:
4548: /*
1.27 markus 4549: * Requests forwarding of X11 connections, generates fake authentication
4550: * data, and enables authentication spoofing.
1.121 markus 4551: * This should be called in the client only.
1.27 markus 4552: */
1.49 markus 4553: void
1.367 djm 4554: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4555: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4556: {
1.367 djm 4557: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4558: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4559: u_int i, value;
1.367 djm 4560: const char *cp;
1.25 markus 4561: char *new_data;
1.367 djm 4562: int r, screen_number;
1.25 markus 4563:
1.367 djm 4564: if (sc->x11_saved_display == NULL)
4565: sc->x11_saved_display = xstrdup(disp);
4566: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4567: error("x11_request_forwarding_with_spoofing: different "
4568: "$DISPLAY already forwarded");
4569: return;
4570: }
4571:
1.266 djm 4572: cp = strchr(disp, ':');
1.25 markus 4573: if (cp)
4574: cp = strchr(cp, '.');
4575: if (cp)
1.245 deraadt 4576: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4577: else
4578: screen_number = 0;
4579:
1.367 djm 4580: if (sc->x11_saved_proto == NULL) {
1.219 djm 4581: /* Save protocol name. */
1.367 djm 4582: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4583:
4584: /* Extract real authentication data. */
1.367 djm 4585: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4586: for (i = 0; i < data_len; i++) {
4587: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4588: fatal("x11_request_forwarding: bad "
4589: "authentication data: %.100s", data);
1.367 djm 4590: sc->x11_saved_data[i] = value;
1.219 djm 4591: }
1.367 djm 4592: sc->x11_saved_data_len = data_len;
1.353 natano 4593:
4594: /* Generate fake data of the same length. */
1.367 djm 4595: sc->x11_fake_data = xmalloc(data_len);
4596: arc4random_buf(sc->x11_fake_data, data_len);
4597: sc->x11_fake_data_len = data_len;
1.25 markus 4598: }
4599:
4600: /* Convert the fake data into hex. */
1.367 djm 4601: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 4602:
4603: /* Send the request packet. */
1.367 djm 4604: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4605: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4606: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4607: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4608: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4609: (r = sshpkt_send(ssh)) != 0 ||
4610: (r = ssh_packet_write_wait(ssh)) != 0)
4611: fatal("%s: send x11-req: %s", __func__, ssh_err(r));
1.321 djm 4612: free(new_data);
1.1 deraadt 4613: }