Annotation of src/usr.bin/ssh/channels.c, Revision 1.373
1.373 ! djm 1: /* $OpenBSD: channels.c,v 1.372 2017/09/21 19:16:53 markus Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.336 millert 43: #include <sys/stat.h>
1.234 stevesk 44: #include <sys/ioctl.h>
1.235 stevesk 45: #include <sys/un.h>
1.251 stevesk 46: #include <sys/socket.h>
1.261 stevesk 47: #include <sys/time.h>
1.275 djm 48: #include <sys/queue.h>
1.251 stevesk 49:
50: #include <netinet/in.h>
51: #include <arpa/inet.h>
1.233 stevesk 52:
1.254 stevesk 53: #include <errno.h>
1.298 dtucker 54: #include <fcntl.h>
1.367 djm 55: #include <limits.h>
1.255 stevesk 56: #include <netdb.h>
1.367 djm 57: #include <stdarg.h>
1.341 millert 58: #include <stdint.h>
1.263 stevesk 59: #include <stdio.h>
1.262 stevesk 60: #include <stdlib.h>
1.260 stevesk 61: #include <string.h>
1.233 stevesk 62: #include <termios.h>
1.256 stevesk 63: #include <unistd.h>
1.1 deraadt 64:
1.265 deraadt 65: #include "xmalloc.h"
1.1 deraadt 66: #include "ssh.h"
1.82 markus 67: #include "ssh2.h"
1.354 markus 68: #include "ssherr.h"
1.367 djm 69: #include "sshbuf.h"
1.1 deraadt 70: #include "packet.h"
1.82 markus 71: #include "log.h"
72: #include "misc.h"
1.14 markus 73: #include "channels.h"
74: #include "compat.h"
1.82 markus 75: #include "canohost.h"
1.64 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:
1.226 djm 1661: static void
1662: channel_set_reuseaddr(int fd)
1663: {
1664: int on = 1;
1665:
1666: /*
1667: * Set socket options.
1668: * Allow local port reuse in TIME_WAIT.
1669: */
1670: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1671: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1.347 djm 1672: }
1673:
1674: void
1.367 djm 1675: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1676: {
1.367 djm 1677: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1678: }
1679:
1.41 markus 1680: /*
1681: * This socket is listening for connections to a forwarded TCP/IP port.
1682: */
1.127 itojun 1683: static void
1.367 djm 1684: channel_post_port_listener(struct ssh *ssh, Channel *c,
1685: fd_set *readset, fd_set *writeset)
1.41 markus 1686: {
1.103 markus 1687: Channel *nc;
1.285 djm 1688: struct sockaddr_storage addr;
1.113 markus 1689: int newsock, nextstate;
1.41 markus 1690: socklen_t addrlen;
1.103 markus 1691: char *rtype;
1.73 markus 1692:
1.367 djm 1693: if (!FD_ISSET(c->sock, readset))
1694: return;
1695:
1696: debug("Connection to port %d forwarding to %.100s port %d requested.",
1697: c->listening_port, c->path, c->host_port);
1.103 markus 1698:
1.367 djm 1699: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1700: nextstate = SSH_CHANNEL_OPENING;
1701: rtype = "forwarded-tcpip";
1702: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1703: nextstate = SSH_CHANNEL_OPENING;
1704: rtype = "forwarded-streamlocal@openssh.com";
1705: } else if (c->host_port == PORT_STREAMLOCAL) {
1706: nextstate = SSH_CHANNEL_OPENING;
1707: rtype = "direct-streamlocal@openssh.com";
1708: } else if (c->host_port == 0) {
1709: nextstate = SSH_CHANNEL_DYNAMIC;
1710: rtype = "dynamic-tcpip";
1711: } else {
1712: nextstate = SSH_CHANNEL_OPENING;
1713: rtype = "direct-tcpip";
1714: }
1.103 markus 1715:
1.367 djm 1716: addrlen = sizeof(addr);
1717: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1718: if (newsock < 0) {
1719: if (errno != EINTR && errno != EWOULDBLOCK &&
1720: errno != ECONNABORTED)
1721: error("accept: %.100s", strerror(errno));
1722: if (errno == EMFILE || errno == ENFILE)
1723: c->notbefore = monotime() + 1;
1724: return;
1.41 markus 1725: }
1.367 djm 1726: if (c->host_port != PORT_STREAMLOCAL)
1727: set_nodelay(newsock);
1728: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1729: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1730: nc->listening_port = c->listening_port;
1731: nc->host_port = c->host_port;
1732: if (c->path != NULL)
1733: nc->path = xstrdup(c->path);
1734:
1735: if (nextstate != SSH_CHANNEL_DYNAMIC)
1736: port_open_helper(ssh, nc, rtype);
1.41 markus 1737: }
1.25 markus 1738:
1.41 markus 1739: /*
1740: * This is the authentication agent socket listening for connections from
1741: * clients.
1742: */
1.127 itojun 1743: static void
1.367 djm 1744: channel_post_auth_listener(struct ssh *ssh, Channel *c,
1745: fd_set *readset, fd_set *writeset)
1.41 markus 1746: {
1.113 markus 1747: Channel *nc;
1.367 djm 1748: int r, newsock;
1.285 djm 1749: struct sockaddr_storage addr;
1.41 markus 1750: socklen_t addrlen;
1.25 markus 1751:
1.367 djm 1752: if (!FD_ISSET(c->sock, readset))
1753: return;
1754:
1755: addrlen = sizeof(addr);
1756: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1757: if (newsock < 0) {
1758: error("accept from auth socket: %.100s", strerror(errno));
1759: if (errno == EMFILE || errno == ENFILE)
1760: c->notbefore = monotime() + 1;
1761: return;
1.41 markus 1762: }
1.367 djm 1763: nc = channel_new(ssh, "accepted auth socket",
1764: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1765: c->local_window_max, c->local_maxpacket,
1766: 0, "accepted auth socket", 1);
1767: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1768: if ((r = sshpkt_send(ssh)) != 0)
1769: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.41 markus 1770: }
1.25 markus 1771:
1.127 itojun 1772: static void
1.367 djm 1773: channel_post_connecting(struct ssh *ssh, Channel *c,
1774: fd_set *readset, fd_set *writeset)
1.75 markus 1775: {
1.372 markus 1776: int err = 0, sock, isopen, r;
1.129 stevesk 1777: socklen_t sz = sizeof(err);
1.114 markus 1778:
1.367 djm 1779: if (!FD_ISSET(c->sock, writeset))
1780: return;
1.368 djm 1781: if (!c->have_remote_id)
1782: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.372 markus 1783: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1784: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.367 djm 1785: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1786: err = errno;
1787: error("getsockopt SO_ERROR failed");
1788: }
1789: if (err == 0) {
1790: debug("channel %d: connected to %s port %d",
1791: c->self, c->connect_ctx.host, c->connect_ctx.port);
1792: channel_connect_ctx_free(&c->connect_ctx);
1793: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1794: if (isopen) {
1795: /* no message necessary */
1796: } else {
1797: if ((r = sshpkt_start(ssh,
1798: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1799: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1800: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1801: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1802: (r = sshpkt_put_u32(ssh, c->local_maxpacket))
1803: != 0)
1804: fatal("%s: channel %i: confirm: %s", __func__,
1805: c->self, ssh_err(r));
1806: if ((r = sshpkt_send(ssh)) != 0)
1807: fatal("%s: channel %i: %s", __func__, c->self,
1808: ssh_err(r));
1.367 djm 1809: }
1810: } else {
1811: debug("channel %d: connection failed: %s",
1812: c->self, strerror(err));
1813: /* Try next address, if any */
1814: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1815: close(c->sock);
1816: c->sock = c->rfd = c->wfd = sock;
1817: channel_find_maxfd(ssh->chanctxt);
1818: return;
1819: }
1820: /* Exhausted all addresses */
1821: error("connect_to %.100s port %d: failed.",
1822: c->connect_ctx.host, c->connect_ctx.port);
1823: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1824: if (isopen) {
1825: rdynamic_close(ssh, c);
1826: } else {
1827: if ((r = sshpkt_start(ssh,
1828: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1829: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1830: (r = sshpkt_put_u32(ssh, SSH2_OPEN_CONNECT_FAILED))
1831: != 0)
1832: fatal("%s: channel %i: failure: %s", __func__,
1833: c->self, ssh_err(r));
1834: if ((datafellows & SSH_BUG_OPENFAILURE) == 0 &&
1835: ((r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1836: (r = sshpkt_put_cstring(ssh, "")) != 0))
1837: fatal("%s: channel %i: failure: %s", __func__,
1838: c->self, ssh_err(r));
1839: if ((r = sshpkt_send(ssh)) != 0)
1840: fatal("%s: channel %i: %s", __func__, c->self,
1841: ssh_err(r));
1842: chan_mark_dead(ssh, c);
1.75 markus 1843: }
1844: }
1845: }
1846:
1.127 itojun 1847: static int
1.367 djm 1848: channel_handle_rfd(struct ssh *ssh, Channel *c,
1849: fd_set *readset, fd_set *writeset)
1.41 markus 1850: {
1.214 markus 1851: char buf[CHAN_RBUF];
1.367 djm 1852: ssize_t len;
1853: int r;
1.25 markus 1854:
1.367 djm 1855: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
1856: return 1;
1857:
1858: len = read(c->rfd, buf, sizeof(buf));
1859: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1860: return 1;
1861: if (len <= 0) {
1862: debug2("channel %d: read<=0 rfd %d len %zd",
1863: c->self, c->rfd, len);
1864: if (c->type != SSH_CHANNEL_OPEN) {
1865: debug2("channel %d: not open", c->self);
1866: chan_mark_dead(ssh, c);
1.41 markus 1867: return -1;
1.65 markus 1868: } else {
1.367 djm 1869: chan_read_failed(ssh, c);
1.65 markus 1870: }
1.367 djm 1871: return -1;
1872: }
1873: if (c->input_filter != NULL) {
1874: if (c->input_filter(ssh, c, buf, len) == -1) {
1875: debug2("channel %d: filter stops", c->self);
1876: chan_read_failed(ssh, c);
1877: }
1878: } else if (c->datagram) {
1879: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1880: fatal("%s: channel %d: put datagram: %s", __func__,
1881: c->self, ssh_err(r));
1882: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
1883: fatal("%s: channel %d: put data: %s", __func__,
1884: c->self, ssh_err(r));
1.41 markus 1885: }
1886: return 1;
1887: }
1.241 deraadt 1888:
1.127 itojun 1889: static int
1.367 djm 1890: channel_handle_wfd(struct ssh *ssh, Channel *c,
1891: fd_set *readset, fd_set *writeset)
1.41 markus 1892: {
1.95 markus 1893: struct termios tio;
1.367 djm 1894: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1895: size_t dlen, olen = 0;
1896: int r, len;
1897:
1898: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
1899: sshbuf_len(c->output) == 0)
1900: return 1;
1.25 markus 1901:
1.41 markus 1902: /* Send buffered output data to the socket. */
1.367 djm 1903: olen = sshbuf_len(c->output);
1904: if (c->output_filter != NULL) {
1905: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1906: debug2("channel %d: filter stops", c->self);
1907: if (c->type != SSH_CHANNEL_OPEN)
1908: chan_mark_dead(ssh, c);
1909: else
1910: chan_write_failed(ssh, c);
1911: return -1;
1.231 reyk 1912: }
1.367 djm 1913: } else if (c->datagram) {
1914: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1915: fatal("%s: channel %d: get datagram: %s", __func__,
1916: c->self, ssh_err(r));
1.369 djm 1917: buf = data;
1.367 djm 1918: } else {
1919: buf = data = sshbuf_mutable_ptr(c->output);
1920: dlen = sshbuf_len(c->output);
1921: }
1.231 reyk 1922:
1.367 djm 1923: if (c->datagram) {
1924: /* ignore truncated writes, datagrams might get lost */
1925: len = write(c->wfd, data, dlen);
1926: free(data);
1.53 markus 1927: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1928: return 1;
1.367 djm 1929: if (len <= 0)
1930: goto write_fail;
1931: goto out;
1932: }
1933:
1934: len = write(c->wfd, buf, dlen);
1935: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1936: return 1;
1937: if (len <= 0) {
1938: write_fail:
1939: if (c->type != SSH_CHANNEL_OPEN) {
1940: debug2("channel %d: not open", c->self);
1941: chan_mark_dead(ssh, c);
1.41 markus 1942: return -1;
1.367 djm 1943: } else {
1944: chan_write_failed(ssh, c);
1.91 markus 1945: }
1.367 djm 1946: return -1;
1947: }
1948: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
1949: if (tcgetattr(c->wfd, &tio) == 0 &&
1950: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1951: /*
1952: * Simulate echo to reduce the impact of
1953: * traffic analysis. We need to match the
1954: * size of a SSH2_MSG_CHANNEL_DATA message
1955: * (4 byte channel id + buf)
1956: */
1957: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
1958: (r = sshpkt_send(ssh)) != 0)
1959: fatal("%s: channel %d: ignore: %s",
1960: __func__, c->self, ssh_err(r));
1.25 markus 1961: }
1.367 djm 1962: }
1963: if ((r = sshbuf_consume(c->output, len)) != 0) {
1964: fatal("%s: channel %d: consume: %s",
1965: __func__, c->self, ssh_err(r));
1.44 markus 1966: }
1.309 djm 1967: out:
1.367 djm 1968: c->local_consumed += olen - sshbuf_len(c->output);
1969:
1970: return 1;
1971: }
1972:
1973: static int
1974: channel_handle_efd_write(struct ssh *ssh, Channel *c,
1975: fd_set *readset, fd_set *writeset)
1976: {
1977: int r;
1978: ssize_t len;
1979:
1980: if (!FD_ISSET(c->efd, writeset) || sshbuf_len(c->extended) == 0)
1981: return 1;
1982:
1983: len = write(c->efd, sshbuf_ptr(c->extended),
1984: sshbuf_len(c->extended));
1985: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1986: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1987: return 1;
1988: if (len <= 0) {
1989: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1990: channel_close_fd(ssh, &c->efd);
1991: } else {
1992: if ((r = sshbuf_consume(c->extended, len)) != 0) {
1993: fatal("%s: channel %d: consume: %s",
1994: __func__, c->self, ssh_err(r));
1995: }
1996: c->local_consumed += len;
1997: }
1.44 markus 1998: return 1;
1999: }
1.241 deraadt 2000:
1.127 itojun 2001: static int
1.367 djm 2002: channel_handle_efd_read(struct ssh *ssh, Channel *c,
2003: fd_set *readset, fd_set *writeset)
1.44 markus 2004: {
1.214 markus 2005: char buf[CHAN_RBUF];
1.367 djm 2006: int r;
2007: ssize_t len;
2008:
2009: if (!FD_ISSET(c->efd, readset))
2010: return 1;
1.44 markus 2011:
1.367 djm 2012: len = read(c->efd, buf, sizeof(buf));
2013: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
2014: if (len < 0 && (errno == EINTR || errno == EAGAIN))
2015: return 1;
2016: if (len <= 0) {
2017: debug2("channel %d: closing read-efd %d",
2018: c->self, c->efd);
2019: channel_close_fd(ssh, &c->efd);
2020: } else {
2021: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
2022: debug3("channel %d: discard efd",
2023: c->self);
2024: } else if ((r = sshbuf_put(c->extended, buf, len)) != 0) {
2025: fatal("%s: channel %d: append: %s",
2026: __func__, c->self, ssh_err(r));
1.44 markus 2027: }
2028: }
2029: return 1;
2030: }
1.241 deraadt 2031:
1.127 itojun 2032: static int
1.367 djm 2033: channel_handle_efd(struct ssh *ssh, Channel *c,
2034: fd_set *readset, fd_set *writeset)
1.44 markus 2035: {
1.367 djm 2036: if (c->efd == -1)
2037: return 1;
2038:
2039: /** XXX handle drain efd, too */
2040:
2041: if (c->extended_usage == CHAN_EXTENDED_WRITE)
2042: return channel_handle_efd_write(ssh, c, readset, writeset);
2043: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2044: c->extended_usage == CHAN_EXTENDED_IGNORE)
2045: return channel_handle_efd_read(ssh, c, readset, writeset);
2046:
2047: return 1;
2048: }
2049:
2050: static int
2051: channel_check_window(struct ssh *ssh, Channel *c)
2052: {
2053: int r;
2054:
1.104 markus 2055: if (c->type == SSH_CHANNEL_OPEN &&
2056: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2057: ((c->local_window_max - c->local_window >
1.269 markus 2058: c->local_maxpacket*3) ||
2059: c->local_window < c->local_window_max/2) &&
1.44 markus 2060: c->local_consumed > 0) {
1.368 djm 2061: if (!c->have_remote_id)
2062: fatal(":%s: channel %d: no remote id",
2063: __func__, c->self);
1.367 djm 2064: if ((r = sshpkt_start(ssh,
2065: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2066: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2067: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2068: (r = sshpkt_send(ssh)) != 0) {
2069: fatal("%s: channel %i: %s", __func__,
2070: c->self, ssh_err(r));
2071: }
1.70 markus 2072: debug2("channel %d: window %d sent adjust %d",
1.44 markus 2073: c->self, c->local_window,
2074: c->local_consumed);
2075: c->local_window += c->local_consumed;
2076: c->local_consumed = 0;
1.1 deraadt 2077: }
1.41 markus 2078: return 1;
1.1 deraadt 2079: }
2080:
1.127 itojun 2081: static void
1.367 djm 2082: channel_post_open(struct ssh *ssh, Channel *c,
2083: fd_set *readset, fd_set *writeset)
1.41 markus 2084: {
1.367 djm 2085: channel_handle_rfd(ssh, c, readset, writeset);
2086: channel_handle_wfd(ssh, c, readset, writeset);
2087: channel_handle_efd(ssh, c, readset, writeset);
2088: channel_check_window(ssh, c);
1.44 markus 2089: }
2090:
1.302 djm 2091: static u_int
1.367 djm 2092: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2093: {
2094: char buf[CHAN_RBUF];
1.367 djm 2095: ssize_t len;
1.302 djm 2096: u_int rlen;
1.367 djm 2097: int r;
1.302 djm 2098:
1.367 djm 2099: if (sshbuf_len(c->input) < need) {
2100: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2101: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.349 naddy 2102: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2103: return sshbuf_len(c->input);
1.302 djm 2104: if (len <= 0) {
1.367 djm 2105: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2106: c->self, c->rfd, len);
1.367 djm 2107: chan_read_failed(ssh, c);
1.349 naddy 2108: return 0;
1.367 djm 2109: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
2110: fatal("%s: channel %d: append: %s",
2111: __func__, c->self, ssh_err(r));
2112: }
1.302 djm 2113: }
1.367 djm 2114: return sshbuf_len(c->input);
1.302 djm 2115: }
2116:
2117: static void
1.367 djm 2118: channel_post_mux_client_read(struct ssh *ssh, Channel *c,
2119: fd_set *readset, fd_set *writeset)
1.302 djm 2120: {
2121: u_int need;
2122:
1.367 djm 2123: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
2124: return;
2125: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2126: return;
2127: if (c->mux_pause)
2128: return;
2129:
2130: /*
2131: * Don't not read past the precise end of packets to
2132: * avoid disrupting fd passing.
2133: */
2134: if (read_mux(ssh, c, 4) < 4) /* read header */
2135: return;
2136: /* XXX sshbuf_peek_u32 */
2137: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2138: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2139: if (need > CHANNEL_MUX_MAX_PACKET) {
2140: debug2("channel %d: packet too big %u > %u",
2141: c->self, CHANNEL_MUX_MAX_PACKET, need);
2142: chan_rcvd_oclose(ssh, c);
2143: return;
2144: }
2145: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2146: return;
2147: if (c->mux_rcb(ssh, c) != 0) {
2148: debug("channel %d: mux_rcb failed", c->self);
2149: chan_mark_dead(ssh, c);
2150: return;
1.302 djm 2151: }
1.367 djm 2152: }
2153:
2154: static void
2155: channel_post_mux_client_write(struct ssh *ssh, Channel *c,
2156: fd_set *readset, fd_set *writeset)
2157: {
2158: ssize_t len;
2159: int r;
1.302 djm 2160:
1.367 djm 2161: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
2162: sshbuf_len(c->output) == 0)
2163: return;
2164:
2165: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
2166: if (len < 0 && (errno == EINTR || errno == EAGAIN))
2167: return;
2168: if (len <= 0) {
2169: chan_mark_dead(ssh, c);
2170: return;
1.302 djm 2171: }
1.367 djm 2172: if ((r = sshbuf_consume(c->output, len)) != 0)
2173: fatal("%s: channel %d: consume: %s", __func__,
2174: c->self, ssh_err(r));
2175: }
2176:
2177: static void
2178: channel_post_mux_client(struct ssh *ssh, Channel *c,
2179: fd_set *readset, fd_set *writeset)
2180: {
2181: channel_post_mux_client_read(ssh, c, readset, writeset);
2182: channel_post_mux_client_write(ssh, c, readset, writeset);
1.302 djm 2183: }
2184:
2185: static void
1.367 djm 2186: channel_post_mux_listener(struct ssh *ssh, Channel *c,
2187: fd_set *readset, fd_set *writeset)
1.302 djm 2188: {
2189: Channel *nc;
2190: struct sockaddr_storage addr;
2191: socklen_t addrlen;
2192: int newsock;
2193: uid_t euid;
2194: gid_t egid;
2195:
2196: if (!FD_ISSET(c->sock, readset))
2197: return;
2198:
2199: debug("multiplexing control connection");
2200:
2201: /*
2202: * Accept connection on control socket
2203: */
2204: memset(&addr, 0, sizeof(addr));
2205: addrlen = sizeof(addr);
2206: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2207: &addrlen)) == -1) {
2208: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 2209: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2210: c->notbefore = monotime() + 1;
1.302 djm 2211: return;
2212: }
2213:
2214: if (getpeereid(newsock, &euid, &egid) < 0) {
2215: error("%s getpeereid failed: %s", __func__,
2216: strerror(errno));
2217: close(newsock);
2218: return;
2219: }
2220: if ((euid != 0) && (getuid() != euid)) {
2221: error("multiplex uid mismatch: peer euid %u != uid %u",
2222: (u_int)euid, (u_int)getuid());
2223: close(newsock);
2224: return;
2225: }
1.367 djm 2226: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2227: newsock, newsock, -1, c->local_window_max,
2228: c->local_maxpacket, 0, "mux-control", 1);
2229: nc->mux_rcb = c->mux_rcb;
1.367 djm 2230: debug3("%s: new mux channel %d fd %d", __func__, nc->self, nc->sock);
1.302 djm 2231: /* establish state */
1.367 djm 2232: nc->mux_rcb(ssh, nc);
1.302 djm 2233: /* mux state transitions must not elicit protocol messages */
2234: nc->flags |= CHAN_LOCAL;
2235: }
2236:
1.127 itojun 2237: static void
1.367 djm 2238: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2239: {
1.367 djm 2240: chan_fn **pre, **post;
2241:
2242: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
2243: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
2244: fatal("%s: allocation failed", __func__);
2245:
2246: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2247: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2248: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2249: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2250: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2251: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2252: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2253: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2254: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2255: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2256: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2257: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2258: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2259:
2260: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2261: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2262: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2263: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2264: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2265: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2266: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2267: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2268: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2269: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2270: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2271: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2272:
1.367 djm 2273: sc->channel_pre = pre;
2274: sc->channel_post = post;
1.44 markus 2275: }
2276:
1.140 markus 2277: /* gc dead channels */
2278: static void
1.367 djm 2279: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2280: {
2281: if (c == NULL)
2282: return;
2283: if (c->detach_user != NULL) {
1.367 djm 2284: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2285: return;
1.194 markus 2286: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2287: c->detach_user(ssh, c->self, NULL);
1.140 markus 2288: /* if we still have a callback */
2289: if (c->detach_user != NULL)
2290: return;
1.194 markus 2291: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2292: }
1.367 djm 2293: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2294: return;
1.194 markus 2295: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2296: channel_free(ssh, c);
1.140 markus 2297: }
2298:
1.367 djm 2299: enum channel_table { CHAN_PRE, CHAN_POST };
2300:
1.127 itojun 2301: static void
1.367 djm 2302: channel_handler(struct ssh *ssh, int table,
1.366 djm 2303: fd_set *readset, fd_set *writeset, time_t *unpause_secs)
1.41 markus 2304: {
1.367 djm 2305: struct ssh_channels *sc = ssh->chanctxt;
2306: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2307: u_int i, oalloc;
1.41 markus 2308: Channel *c;
1.317 djm 2309: time_t now;
1.25 markus 2310:
1.322 dtucker 2311: now = monotime();
1.317 djm 2312: if (unpause_secs != NULL)
2313: *unpause_secs = 0;
1.367 djm 2314: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2315: c = sc->channels[i];
1.113 markus 2316: if (c == NULL)
1.41 markus 2317: continue;
1.299 markus 2318: if (c->delayed) {
1.367 djm 2319: if (table == CHAN_PRE)
1.299 markus 2320: c->delayed = 0;
2321: else
2322: continue;
2323: }
1.317 djm 2324: if (ftab[c->type] != NULL) {
2325: /*
2326: * Run handlers that are not paused.
2327: */
2328: if (c->notbefore <= now)
1.367 djm 2329: (*ftab[c->type])(ssh, c, readset, writeset);
1.317 djm 2330: else if (unpause_secs != NULL) {
2331: /*
2332: * Collect the time that the earliest
2333: * channel comes off pause.
2334: */
2335: debug3("%s: chan %d: skip for %d more seconds",
2336: __func__, c->self,
2337: (int)(c->notbefore - now));
2338: if (*unpause_secs == 0 ||
2339: (c->notbefore - now) < *unpause_secs)
2340: *unpause_secs = c->notbefore - now;
2341: }
2342: }
1.367 djm 2343: channel_garbage_collect(ssh, c);
1.1 deraadt 2344: }
1.317 djm 2345: if (unpause_secs != NULL && *unpause_secs != 0)
2346: debug3("%s: first channel unpauses in %d seconds",
2347: __func__, (int)*unpause_secs);
1.1 deraadt 2348: }
2349:
1.121 markus 2350: /*
1.372 markus 2351: * Create sockets before allocating the select bitmasks.
2352: * This is necessary for things that need to happen after reading
2353: * the network-input but before channel_prepare_select().
2354: */
2355: static void
2356: channel_before_prepare_select(struct ssh *ssh)
2357: {
2358: struct ssh_channels *sc = ssh->chanctxt;
2359: Channel *c;
2360: u_int i, oalloc;
2361:
2362: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2363: c = sc->channels[i];
2364: if (c == NULL)
2365: continue;
2366: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
2367: channel_before_prepare_select_rdynamic(ssh, c);
2368: }
2369: }
2370:
2371: /*
1.121 markus 2372: * Allocate/update select bitmasks and add any bits relevant to channels in
2373: * select bitmasks.
2374: */
1.49 markus 2375: void
1.366 djm 2376: channel_prepare_select(struct ssh *ssh, fd_set **readsetp, fd_set **writesetp,
2377: int *maxfdp, u_int *nallocp, time_t *minwait_secs)
1.41 markus 2378: {
1.243 djm 2379: u_int n, sz, nfdset;
1.84 markus 2380:
1.372 markus 2381: channel_before_prepare_select(ssh); /* might update channel_max_fd */
2382:
1.367 djm 2383: n = MAXIMUM(*maxfdp, ssh->chanctxt->channel_max_fd);
1.84 markus 2384:
1.243 djm 2385: nfdset = howmany(n+1, NFDBITS);
2386: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2387: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2388: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2389: sz = nfdset * sizeof(fd_mask);
2390:
1.132 markus 2391: /* perhaps check sz < nalloc/2 and shrink? */
2392: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2393: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2394: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2395: *nallocp = sz;
1.84 markus 2396: }
1.132 markus 2397: *maxfdp = n;
1.84 markus 2398: memset(*readsetp, 0, sz);
2399: memset(*writesetp, 0, sz);
2400:
1.366 djm 2401: if (!ssh_packet_is_rekeying(ssh))
1.367 djm 2402: channel_handler(ssh, CHAN_PRE, *readsetp, *writesetp,
1.317 djm 2403: minwait_secs);
1.41 markus 2404: }
2405:
1.121 markus 2406: /*
2407: * After select, perform any appropriate operations for channels which have
2408: * events pending.
2409: */
1.49 markus 2410: void
1.366 djm 2411: channel_after_select(struct ssh *ssh, fd_set *readset, fd_set *writeset)
1.41 markus 2412: {
1.367 djm 2413: channel_handler(ssh, CHAN_POST, readset, writeset, NULL);
2414: }
2415:
2416: /*
2417: * Enqueue data for channels with open or draining c->input.
2418: */
2419: static void
2420: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2421: {
1.373 ! djm 2422: size_t len, plen;
! 2423: const u_char *pkt;
1.367 djm 2424: int r;
2425:
2426: if ((len = sshbuf_len(c->input)) == 0) {
2427: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2428: /*
2429: * input-buffer is empty and read-socket shutdown:
2430: * tell peer, that we will not send more data:
2431: * send IEOF.
2432: * hack for extended data: delay EOF if EFD still
2433: * in use.
2434: */
2435: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2436: debug2("channel %d: "
2437: "ibuf_empty delayed efd %d/(%zu)",
2438: c->self, c->efd, sshbuf_len(c->extended));
2439: else
2440: chan_ibuf_empty(ssh, c);
2441: }
2442: return;
2443: }
2444:
1.368 djm 2445: if (!c->have_remote_id)
2446: fatal(":%s: channel %d: no remote id", __func__, c->self);
2447:
1.367 djm 2448: if (c->datagram) {
2449: /* Check datagram will fit; drop if not */
1.373 ! djm 2450: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
! 2451: fatal("%s: channel %d: get datagram: %s", __func__,
1.367 djm 2452: c->self, ssh_err(r));
2453: /*
2454: * XXX this does tail-drop on the datagram queue which is
2455: * usually suboptimal compared to head-drop. Better to have
2456: * backpressure at read time? (i.e. read + discard)
2457: */
1.373 ! djm 2458: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2459: debug("channel %d: datagram too big", c->self);
2460: return;
2461: }
2462: /* Enqueue it */
2463: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2464: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 ! djm 2465: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.367 djm 2466: (r = sshpkt_send(ssh)) != 0) {
2467: fatal("%s: channel %i: datagram: %s", __func__,
2468: c->self, ssh_err(r));
2469: }
1.373 ! djm 2470: c->remote_window -= plen;
1.367 djm 2471: return;
2472: }
2473:
2474: /* Enqueue packet for buffered data. */
2475: if (len > c->remote_window)
2476: len = c->remote_window;
2477: if (len > c->remote_maxpacket)
2478: len = c->remote_maxpacket;
2479: if (len == 0)
2480: return;
2481: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2482: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2483: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
2484: (r = sshpkt_send(ssh)) != 0) {
2485: fatal("%s: channel %i: data: %s", __func__,
2486: c->self, ssh_err(r));
2487: }
2488: if ((r = sshbuf_consume(c->input, len)) != 0)
2489: fatal("%s: channel %i: consume: %s", __func__,
2490: c->self, ssh_err(r));
2491: c->remote_window -= len;
1.41 markus 2492: }
2493:
1.367 djm 2494: /*
2495: * Enqueue data for channels with open c->extended in read mode.
2496: */
2497: static void
2498: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2499: {
2500: size_t len;
2501: int r;
2502:
2503: if ((len = sshbuf_len(c->extended)) == 0)
2504: return;
2505:
2506: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2507: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2508: if (len > c->remote_window)
2509: len = c->remote_window;
2510: if (len > c->remote_maxpacket)
2511: len = c->remote_maxpacket;
2512: if (len == 0)
2513: return;
1.368 djm 2514: if (!c->have_remote_id)
2515: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.367 djm 2516: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2517: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2518: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2519: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
2520: (r = sshpkt_send(ssh)) != 0) {
2521: fatal("%s: channel %i: data: %s", __func__,
2522: c->self, ssh_err(r));
2523: }
2524: if ((r = sshbuf_consume(c->extended, len)) != 0)
2525: fatal("%s: channel %i: consume: %s", __func__,
2526: c->self, ssh_err(r));
2527: c->remote_window -= len;
2528: debug2("channel %d: sent ext data %zu", c->self, len);
2529: }
1.121 markus 2530:
1.84 markus 2531: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2532: void
1.367 djm 2533: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2534: {
1.367 djm 2535: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2536: Channel *c;
1.367 djm 2537: u_int i;
1.1 deraadt 2538:
1.367 djm 2539: for (i = 0; i < sc->channels_alloc; i++) {
2540: c = sc->channels[i];
1.113 markus 2541: if (c == NULL)
2542: continue;
1.37 markus 2543:
1.121 markus 2544: /*
2545: * We are only interested in channels that can have buffered
2546: * incoming data.
2547: */
1.358 djm 2548: if (c->type != SSH_CHANNEL_OPEN)
2549: continue;
2550: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2551: /* XXX is this true? */
1.367 djm 2552: debug3("channel %d: will not send data after close",
2553: c->self);
1.44 markus 2554: continue;
2555: }
1.25 markus 2556:
2557: /* Get the amount of buffered data for this channel. */
1.367 djm 2558: if (c->istate == CHAN_INPUT_OPEN ||
2559: c->istate == CHAN_INPUT_WAIT_DRAIN)
2560: channel_output_poll_input_open(ssh, c);
1.44 markus 2561: /* Send extended data, i.e. stderr */
1.358 djm 2562: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2563: c->extended_usage == CHAN_EXTENDED_READ)
2564: channel_output_poll_extended_read(ssh, c);
1.25 markus 2565: }
1.1 deraadt 2566: }
2567:
1.354 markus 2568: /* -- mux proxy support */
2569:
2570: /*
2571: * When multiplexing channel messages for mux clients we have to deal
2572: * with downstream messages from the mux client and upstream messages
2573: * from the ssh server:
2574: * 1) Handling downstream messages is straightforward and happens
2575: * in channel_proxy_downstream():
2576: * - We forward all messages (mostly) unmodified to the server.
2577: * - However, in order to route messages from upstream to the correct
2578: * downstream client, we have to replace the channel IDs used by the
2579: * mux clients with a unique channel ID because the mux clients might
2580: * use conflicting channel IDs.
2581: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2582: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2583: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2584: * with the newly allocated channel ID.
2585: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
2586: * channels and procesed by channel_proxy_upstream(). The local channel ID
2587: * is then translated back to the original mux client ID.
2588: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2589: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2590: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2591: * downstream mux client are removed.
2592: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2593: * requires more work, because they are not addressed to a specific
2594: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2595: * out whether the request is addressed to the local client or a
2596: * specific downstream client based on the listen-address/port.
2597: * 6) Agent and X11-Forwarding have a similar problem and are currenly
2598: * not supported as the matching session/channel cannot be identified
2599: * easily.
2600: */
2601:
2602: /*
2603: * receive packets from downstream mux clients:
2604: * channel callback fired on read from mux client, creates
2605: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2606: * on channel creation.
2607: */
2608: int
1.367 djm 2609: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2610: {
2611: Channel *c = NULL;
2612: struct sshbuf *original = NULL, *modified = NULL;
2613: const u_char *cp;
2614: char *ctype = NULL, *listen_host = NULL;
2615: u_char type;
2616: size_t have;
1.370 djm 2617: int ret = -1, r;
1.355 djm 2618: u_int id, remote_id, listen_port;
1.354 markus 2619:
1.367 djm 2620: /* sshbuf_dump(downstream->input, stderr); */
2621: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2622: != 0) {
2623: error("%s: malformed message: %s", __func__, ssh_err(r));
2624: return -1;
2625: }
2626: if (have < 2) {
2627: error("%s: short message", __func__);
2628: return -1;
2629: }
2630: type = cp[1];
2631: /* skip padlen + type */
2632: cp += 2;
2633: have -= 2;
2634: if (ssh_packet_log_type(type))
2635: debug3("%s: channel %u: down->up: type %u", __func__,
2636: downstream->self, type);
2637:
2638: switch (type) {
2639: case SSH2_MSG_CHANNEL_OPEN:
2640: if ((original = sshbuf_from(cp, have)) == NULL ||
2641: (modified = sshbuf_new()) == NULL) {
2642: error("%s: alloc", __func__);
2643: goto out;
2644: }
2645: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2646: (r = sshbuf_get_u32(original, &id)) != 0) {
2647: error("%s: parse error %s", __func__, ssh_err(r));
2648: goto out;
2649: }
1.367 djm 2650: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2651: -1, -1, -1, 0, 0, 0, ctype, 1);
2652: c->mux_ctx = downstream; /* point to mux client */
2653: c->mux_downstream_id = id; /* original downstream id */
2654: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2655: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2656: (r = sshbuf_putb(modified, original)) != 0) {
2657: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2658: channel_free(ssh, c);
1.354 markus 2659: goto out;
2660: }
2661: break;
2662: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2663: /*
2664: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2665: * need to parse 'remote_id' instead of 'ctype'.
2666: */
2667: if ((original = sshbuf_from(cp, have)) == NULL ||
2668: (modified = sshbuf_new()) == NULL) {
2669: error("%s: alloc", __func__);
2670: goto out;
2671: }
2672: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2673: (r = sshbuf_get_u32(original, &id)) != 0) {
2674: error("%s: parse error %s", __func__, ssh_err(r));
2675: goto out;
2676: }
1.367 djm 2677: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2678: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
2679: c->mux_ctx = downstream; /* point to mux client */
2680: c->mux_downstream_id = id;
2681: c->remote_id = remote_id;
1.368 djm 2682: c->have_remote_id = 1;
1.354 markus 2683: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2684: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2685: (r = sshbuf_putb(modified, original)) != 0) {
2686: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2687: channel_free(ssh, c);
1.354 markus 2688: goto out;
2689: }
2690: break;
2691: case SSH2_MSG_GLOBAL_REQUEST:
2692: if ((original = sshbuf_from(cp, have)) == NULL) {
2693: error("%s: alloc", __func__);
2694: goto out;
2695: }
2696: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
2697: error("%s: parse error %s", __func__, ssh_err(r));
2698: goto out;
2699: }
2700: if (strcmp(ctype, "tcpip-forward") != 0) {
2701: error("%s: unsupported request %s", __func__, ctype);
2702: goto out;
2703: }
2704: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2705: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2706: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
2707: error("%s: parse error %s", __func__, ssh_err(r));
2708: goto out;
2709: }
1.355 djm 2710: if (listen_port > 65535) {
2711: error("%s: tcpip-forward for %s: bad port %u",
2712: __func__, listen_host, listen_port);
2713: goto out;
2714: }
1.354 markus 2715: /* Record that connection to this host/port is permitted. */
1.370 djm 2716: fwd_perm_list_add(ssh, FWDPERM_USER, "<mux>", -1,
1.367 djm 2717: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 2718: listen_host = NULL;
2719: break;
2720: case SSH2_MSG_CHANNEL_CLOSE:
2721: if (have < 4)
2722: break;
2723: remote_id = PEEK_U32(cp);
1.367 djm 2724: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 2725: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 2726: channel_free(ssh, c);
1.354 markus 2727: else
2728: c->flags |= CHAN_CLOSE_SENT;
2729: }
2730: break;
2731: }
2732: if (modified) {
2733: if ((r = sshpkt_start(ssh, type)) != 0 ||
2734: (r = sshpkt_putb(ssh, modified)) != 0 ||
2735: (r = sshpkt_send(ssh)) != 0) {
2736: error("%s: send %s", __func__, ssh_err(r));
2737: goto out;
2738: }
2739: } else {
2740: if ((r = sshpkt_start(ssh, type)) != 0 ||
2741: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2742: (r = sshpkt_send(ssh)) != 0) {
2743: error("%s: send %s", __func__, ssh_err(r));
2744: goto out;
2745: }
2746: }
2747: ret = 0;
2748: out:
2749: free(ctype);
2750: free(listen_host);
2751: sshbuf_free(original);
2752: sshbuf_free(modified);
2753: return ret;
2754: }
2755:
2756: /*
2757: * receive packets from upstream server and de-multiplex packets
2758: * to correct downstream:
2759: * implemented as a helper for channel input handlers,
2760: * replaces local (proxy) channel ID with downstream channel ID.
2761: */
2762: int
1.363 markus 2763: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 2764: {
2765: struct sshbuf *b = NULL;
2766: Channel *downstream;
2767: const u_char *cp = NULL;
2768: size_t len;
2769: int r;
2770:
2771: /*
2772: * When receiving packets from the peer we need to check whether we
2773: * need to forward the packets to the mux client. In this case we
2774: * restore the orignal channel id and keep track of CLOSE messages,
2775: * so we can cleanup the channel.
2776: */
2777: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2778: return 0;
2779: if ((downstream = c->mux_ctx) == NULL)
2780: return 0;
2781: switch (type) {
2782: case SSH2_MSG_CHANNEL_CLOSE:
2783: case SSH2_MSG_CHANNEL_DATA:
2784: case SSH2_MSG_CHANNEL_EOF:
2785: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2786: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2787: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2788: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2789: case SSH2_MSG_CHANNEL_SUCCESS:
2790: case SSH2_MSG_CHANNEL_FAILURE:
2791: case SSH2_MSG_CHANNEL_REQUEST:
2792: break;
2793: default:
2794: debug2("%s: channel %u: unsupported type %u", __func__,
2795: c->self, type);
2796: return 0;
2797: }
2798: if ((b = sshbuf_new()) == NULL) {
2799: error("%s: alloc reply", __func__);
2800: goto out;
2801: }
2802: /* get remaining payload (after id) */
2803: cp = sshpkt_ptr(ssh, &len);
2804: if (cp == NULL) {
2805: error("%s: no packet", __func__);
2806: goto out;
2807: }
2808: /* translate id and send to muxclient */
2809: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2810: (r = sshbuf_put_u8(b, type)) != 0 ||
2811: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2812: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 2813: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.354 markus 2814: error("%s: compose for muxclient %s", __func__, ssh_err(r));
2815: goto out;
2816: }
2817: /* sshbuf_dump(b, stderr); */
2818: if (ssh_packet_log_type(type))
2819: debug3("%s: channel %u: up->down: type %u", __func__, c->self,
2820: type);
2821: out:
2822: /* update state */
2823: switch (type) {
2824: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2825: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 2826: if (cp && len > 4) {
1.354 markus 2827: c->remote_id = PEEK_U32(cp);
1.368 djm 2828: c->have_remote_id = 1;
2829: }
1.354 markus 2830: break;
2831: case SSH2_MSG_CHANNEL_CLOSE:
2832: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 2833: channel_free(ssh, c);
1.354 markus 2834: else
2835: c->flags |= CHAN_CLOSE_RCVD;
2836: break;
2837: }
2838: sshbuf_free(b);
2839: return 1;
2840: }
1.121 markus 2841:
2842: /* -- protocol input */
1.249 djm 2843:
1.367 djm 2844: /* Parse a channel ID from the current packet */
2845: static int
2846: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
2847: {
2848: u_int32_t id;
2849: int r;
2850:
2851: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
2852: error("%s: parse id: %s", where, ssh_err(r));
2853: ssh_packet_disconnect(ssh, "Invalid %s message", what);
2854: }
2855: if (id > INT_MAX) {
2856: error("%s: bad channel id %u: %s", where, id, ssh_err(r));
2857: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
2858: }
2859: return (int)id;
2860: }
2861:
2862: /* Lookup a channel from an ID in the current packet */
2863: static Channel *
2864: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
2865: {
2866: int id = channel_parse_id(ssh, where, what);
2867: Channel *c;
2868:
2869: if ((c = channel_lookup(ssh, id)) == NULL) {
2870: ssh_packet_disconnect(ssh,
2871: "%s packet referred to nonexistent channel %d", what, id);
2872: }
2873: return c;
2874: }
2875:
1.339 markus 2876: int
1.363 markus 2877: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2878: {
1.332 djm 2879: const u_char *data;
1.367 djm 2880: size_t data_len, win_len;
2881: Channel *c = channel_from_packet_id(ssh, __func__, "data");
2882: int r;
1.25 markus 2883:
1.363 markus 2884: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2885: return 0;
1.25 markus 2886:
2887: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2888: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 2889: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
2890: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 2891: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2892: return 0;
1.37 markus 2893:
1.25 markus 2894: /* Get the data. */
1.367 djm 2895: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0)
2896: fatal("%s: channel %d: get data: %s", __func__,
2897: c->self, ssh_err(r));
2898: ssh_packet_check_eom(ssh);
2899:
1.309 djm 2900: win_len = data_len;
2901: if (c->datagram)
2902: win_len += 4; /* string length header */
1.200 markus 2903:
2904: /*
1.367 djm 2905: * The sending side reduces its window as it sends data, so we
2906: * must 'fake' consumption of the data in order to ensure that window
2907: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 2908: */
1.358 djm 2909: if (c->ostate != CHAN_OUTPUT_OPEN) {
2910: c->local_window -= win_len;
2911: c->local_consumed += win_len;
1.339 markus 2912: return 0;
1.200 markus 2913: }
1.41 markus 2914:
1.358 djm 2915: if (win_len > c->local_maxpacket) {
1.367 djm 2916: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 2917: c->self, win_len, c->local_maxpacket);
1.367 djm 2918: return 0;
1.358 djm 2919: }
2920: if (win_len > c->local_window) {
1.367 djm 2921: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 2922: c->self, win_len, c->local_window);
2923: return 0;
1.44 markus 2924: }
1.358 djm 2925: c->local_window -= win_len;
2926:
1.367 djm 2927: if (c->datagram) {
2928: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
2929: fatal("%s: channel %d: append datagram: %s",
2930: __func__, c->self, ssh_err(r));
2931: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
2932: fatal("%s: channel %d: append data: %s",
2933: __func__, c->self, ssh_err(r));
2934:
1.339 markus 2935: return 0;
1.1 deraadt 2936: }
1.121 markus 2937:
1.339 markus 2938: int
1.363 markus 2939: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 2940: {
1.367 djm 2941: const u_char *data;
2942: size_t data_len;
2943: u_int32_t tcode;
2944: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
2945: int r;
1.44 markus 2946:
1.363 markus 2947: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2948: return 0;
1.44 markus 2949: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 2950: logit("channel %d: ext data for non open", c->self);
1.339 markus 2951: return 0;
1.172 markus 2952: }
2953: if (c->flags & CHAN_EOF_RCVD) {
2954: if (datafellows & SSH_BUG_EXTEOF)
1.367 djm 2955: debug("channel %d: accepting ext data after eof",
2956: c->self);
1.172 markus 2957: else
1.367 djm 2958: ssh_packet_disconnect(ssh, "Received extended_data "
2959: "after EOF on channel %d.", c->self);
2960: }
2961:
2962: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
2963: error("%s: parse tcode: %s", __func__, ssh_err(r));
2964: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 2965: }
2966: if (c->efd == -1 ||
2967: c->extended_usage != CHAN_EXTENDED_WRITE ||
2968: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2969: logit("channel %d: bad ext data", c->self);
1.339 markus 2970: return 0;
1.44 markus 2971: }
1.367 djm 2972: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0) {
2973: error("%s: parse data: %s", __func__, ssh_err(r));
2974: ssh_packet_disconnect(ssh, "Invalid extended_data message");
2975: }
2976: ssh_packet_check_eom(ssh);
2977:
1.44 markus 2978: if (data_len > c->local_window) {
1.367 djm 2979: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 2980: c->self, data_len, c->local_window);
1.339 markus 2981: return 0;
1.44 markus 2982: }
1.367 djm 2983: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
2984: /* XXX sshpkt_getb? */
2985: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
2986: error("%s: append: %s", __func__, ssh_err(r));
1.44 markus 2987: c->local_window -= data_len;
1.339 markus 2988: return 0;
1.44 markus 2989: }
2990:
1.339 markus 2991: int
1.363 markus 2992: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 2993: {
1.367 djm 2994: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
2995:
2996: ssh_packet_check_eom(ssh);
1.41 markus 2997:
1.363 markus 2998: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2999: return 0;
1.367 djm 3000: chan_rcvd_ieof(ssh, c);
1.133 markus 3001:
3002: /* XXX force input close */
1.156 markus 3003: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3004: debug("channel %d: FORCE input drain", c->self);
3005: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3006: if (sshbuf_len(c->input) == 0)
3007: chan_ibuf_empty(ssh, c);
1.133 markus 3008: }
1.339 markus 3009: return 0;
1.41 markus 3010: }
1.1 deraadt 3011:
1.339 markus 3012: int
1.363 markus 3013: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3014: {
1.367 djm 3015: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.151 markus 3016:
1.363 markus 3017: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3018: return 0;
1.367 djm 3019: ssh_packet_check_eom(ssh);
3020: chan_rcvd_oclose(ssh, c);
1.339 markus 3021: return 0;
1.1 deraadt 3022: }
3023:
1.339 markus 3024: int
1.363 markus 3025: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3026: {
1.367 djm 3027: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3028: u_int32_t remote_window, remote_maxpacket;
3029: int r;
1.25 markus 3030:
1.363 markus 3031: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3032: return 0;
3033: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 3034: packet_disconnect("Received open confirmation for "
1.367 djm 3035: "non-opening channel %d.", c->self);
3036: /*
3037: * Record the remote channel number and mark that the channel
3038: * is now open.
3039: */
1.368 djm 3040: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3041: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.367 djm 3042: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0) {
3043: error("%s: window/maxpacket: %s", __func__, ssh_err(r));
3044: packet_disconnect("Invalid open confirmation message");
3045: }
3046: ssh_packet_check_eom(ssh);
3047:
1.368 djm 3048: c->have_remote_id = 1;
1.367 djm 3049: c->remote_window = remote_window;
3050: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3051: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3052: if (c->open_confirm) {
1.367 djm 3053: debug2("%s: channel %d: callback start", __func__, c->self);
3054: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
3055: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3056: }
1.358 djm 3057: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3058: c->remote_window, c->remote_maxpacket);
1.339 markus 3059: return 0;
1.1 deraadt 3060: }
3061:
1.127 itojun 3062: static char *
1.114 markus 3063: reason2txt(int reason)
3064: {
1.143 deraadt 3065: switch (reason) {
1.114 markus 3066: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3067: return "administratively prohibited";
3068: case SSH2_OPEN_CONNECT_FAILED:
3069: return "connect failed";
3070: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3071: return "unknown channel type";
3072: case SSH2_OPEN_RESOURCE_SHORTAGE:
3073: return "resource shortage";
3074: }
1.117 stevesk 3075: return "unknown reason";
1.114 markus 3076: }
3077:
1.339 markus 3078: int
1.363 markus 3079: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3080: {
1.367 djm 3081: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3082: u_int32_t reason;
3083: char *msg = NULL;
3084: int r;
1.25 markus 3085:
1.363 markus 3086: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3087: return 0;
3088: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 3089: packet_disconnect("Received open failure for "
1.367 djm 3090: "non-opening channel %d.", c->self);
3091: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
3092: error("%s: reason: %s", __func__, ssh_err(r));
3093: packet_disconnect("Invalid open failure message");
3094: }
3095: if ((datafellows & SSH_BUG_OPENFAILURE) == 0) {
3096: /* skip language */
3097: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
3098: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) == 0) {
3099: error("%s: message/lang: %s", __func__, ssh_err(r));
3100: packet_disconnect("Invalid open failure message");
3101: }
1.358 djm 3102: }
1.367 djm 3103: ssh_packet_check_eom(ssh);
3104: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3105: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3106: free(msg);
3107: if (c->open_confirm) {
1.367 djm 3108: debug2("%s: channel %d: callback start", __func__, c->self);
3109: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
3110: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3111: }
1.291 djm 3112: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3113: chan_mark_dead(ssh, c);
1.339 markus 3114: return 0;
1.44 markus 3115: }
3116:
1.339 markus 3117: int
1.363 markus 3118: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3119: {
1.367 djm 3120: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3121: Channel *c;
1.367 djm 3122: u_int32_t adjust;
3123: u_int new_rwin;
3124: int r;
1.1 deraadt 3125:
1.367 djm 3126: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3127: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3128: return 0;
1.372 markus 3129: }
1.367 djm 3130:
1.363 markus 3131: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3132: return 0;
1.367 djm 3133: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0) {
3134: error("%s: adjust: %s", __func__, ssh_err(r));
3135: packet_disconnect("Invalid window adjust message");
3136: }
3137: ssh_packet_check_eom(ssh);
3138: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3139: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3140: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3141: c->self, adjust, c->remote_window);
3142: }
3143: c->remote_window = new_rwin;
1.339 markus 3144: return 0;
1.121 markus 3145: }
1.1 deraadt 3146:
1.339 markus 3147: int
1.363 markus 3148: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3149: {
1.367 djm 3150: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3151: Channel *c;
3152: struct channel_confirm *cc;
3153:
3154: /* Reset keepalive timeout */
1.296 andreas 3155: packet_set_alive_timeouts(0);
1.275 djm 3156:
1.367 djm 3157: debug2("%s: type %d id %d", __func__, type, id);
1.275 djm 3158:
1.367 djm 3159: if ((c = channel_lookup(ssh, id)) == NULL) {
3160: logit("%s: %d: unknown", __func__, id);
1.339 markus 3161: return 0;
1.367 djm 3162: }
1.363 markus 3163: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3164: return 0;
1.367 djm 3165: ssh_packet_check_eom(ssh);
1.275 djm 3166: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3167: return 0;
1.367 djm 3168: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3169: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 3170: explicit_bzero(cc, sizeof(*cc));
1.321 djm 3171: free(cc);
1.339 markus 3172: return 0;
1.275 djm 3173: }
1.121 markus 3174:
3175: /* -- tcp forwarding */
1.135 markus 3176:
3177: void
1.367 djm 3178: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3179: {
1.367 djm 3180: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3181: }
1.121 markus 3182:
1.312 djm 3183:
3184: /*
3185: * Determine whether or not a port forward listens to loopback, the
3186: * specified address or wildcard. On the client, a specified bind
3187: * address will always override gateway_ports. On the server, a
3188: * gateway_ports of 1 (``yes'') will override the client's specification
3189: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3190: * will bind to whatever address the client asked for.
3191: *
3192: * Special-case listen_addrs are:
3193: *
3194: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3195: * "" (empty string), "*" -> wildcard v4/v6
3196: * "localhost" -> loopback v4/v6
1.334 djm 3197: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3198: */
3199: static const char *
3200: channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
1.336 millert 3201: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3202: {
3203: const char *addr = NULL;
3204: int wildcard = 0;
3205:
3206: if (listen_addr == NULL) {
3207: /* No address specified: default to gateway_ports setting */
1.336 millert 3208: if (fwd_opts->gateway_ports)
1.312 djm 3209: wildcard = 1;
1.336 millert 3210: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 3211: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
3212: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3213: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3214: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3215: wildcard = 1;
1.326 djm 3216: /*
3217: * Notify client if they requested a specific listen
3218: * address and it was overridden.
3219: */
3220: if (*listen_addr != '\0' &&
3221: strcmp(listen_addr, "0.0.0.0") != 0 &&
3222: strcmp(listen_addr, "*") != 0) {
3223: packet_send_debug("Forwarding listen address "
3224: "\"%s\" overridden by server "
3225: "GatewayPorts", listen_addr);
3226: }
1.334 djm 3227: } else if (strcmp(listen_addr, "localhost") != 0 ||
3228: strcmp(listen_addr, "127.0.0.1") == 0 ||
3229: strcmp(listen_addr, "::1") == 0) {
3230: /* Accept localhost address when GatewayPorts=yes */
3231: addr = listen_addr;
1.326 djm 3232: }
1.334 djm 3233: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3234: strcmp(listen_addr, "::1") == 0) {
3235: /*
3236: * If a specific IPv4/IPv6 localhost address has been
3237: * requested then accept it even if gateway_ports is in
3238: * effect. This allows the client to prefer IPv4 or IPv6.
3239: */
3240: addr = listen_addr;
1.312 djm 3241: }
3242: if (wildcardp != NULL)
3243: *wildcardp = wildcard;
3244: return addr;
3245: }
3246:
1.160 markus 3247: static int
1.367 djm 3248: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3249: struct Forward *fwd, int *allocated_listen_port,
3250: struct ForwardOptions *fwd_opts)
1.25 markus 3251: {
1.113 markus 3252: Channel *c;
1.226 djm 3253: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3254: struct addrinfo hints, *ai, *aitop;
1.212 djm 3255: const char *host, *addr;
1.35 markus 3256: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3257: in_port_t *lport_p;
1.25 markus 3258:
1.212 djm 3259: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3260:
1.344 millert 3261: if (is_client && fwd->connect_path != NULL) {
3262: host = fwd->connect_path;
3263: } else {
3264: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3265: fwd->listen_host : fwd->connect_host;
3266: if (host == NULL) {
3267: error("No forward host name.");
3268: return 0;
3269: }
3270: if (strlen(host) >= NI_MAXHOST) {
3271: error("Forward host name too long.");
3272: return 0;
3273: }
1.87 markus 3274: }
1.25 markus 3275:
1.312 djm 3276: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.336 millert 3277: addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard,
3278: is_client, fwd_opts);
3279: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 3280: type, wildcard, (addr == NULL) ? "NULL" : addr);
3281:
3282: /*
1.35 markus 3283: * getaddrinfo returns a loopback address if the hostname is
3284: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3285: */
1.35 markus 3286: memset(&hints, 0, sizeof(hints));
1.367 djm 3287: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3288: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3289: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3290: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3291: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3292: if (addr == NULL) {
3293: /* This really shouldn't happen */
3294: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 3295: ssh_gai_strerror(r));
1.212 djm 3296: } else {
1.336 millert 3297: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 3298: ssh_gai_strerror(r));
1.212 djm 3299: }
1.218 markus 3300: return 0;
1.212 djm 3301: }
1.295 djm 3302: if (allocated_listen_port != NULL)
3303: *allocated_listen_port = 0;
1.35 markus 3304: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3305: switch (ai->ai_family) {
3306: case AF_INET:
3307: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3308: sin_port;
3309: break;
3310: case AF_INET6:
3311: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3312: sin6_port;
3313: break;
3314: default:
1.35 markus 3315: continue;
1.295 djm 3316: }
3317: /*
3318: * If allocating a port for -R forwards, then use the
3319: * same port for all address families.
3320: */
1.367 djm 3321: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3322: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3323: *allocated_listen_port > 0)
1.295 djm 3324: *lport_p = htons(*allocated_listen_port);
3325:
1.35 markus 3326: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3327: strport, sizeof(strport),
3328: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 3329: error("%s: getnameinfo failed", __func__);
1.35 markus 3330: continue;
3331: }
3332: /* Create a port to listen for the host. */
1.300 dtucker 3333: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 3334: if (sock < 0) {
3335: /* this is no error since kernel may not support ipv6 */
3336: verbose("socket: %.100s", strerror(errno));
3337: continue;
3338: }
1.226 djm 3339:
3340: channel_set_reuseaddr(sock);
1.182 stevesk 3341:
1.295 djm 3342: debug("Local forwarding listening on %s port %s.",
3343: ntop, strport);
1.35 markus 3344:
3345: /* Bind the socket to the address. */
3346: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.367 djm 3347: /*
3348: * address can be in if use ipv6 address is
3349: * already bound
3350: */
1.35 markus 3351: verbose("bind: %.100s", strerror(errno));
3352: close(sock);
3353: continue;
3354: }
3355: /* Start listening for connections on the socket. */
1.199 markus 3356: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3357: error("listen: %.100s", strerror(errno));
3358: close(sock);
3359: continue;
3360: }
1.295 djm 3361:
3362: /*
1.336 millert 3363: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3364: * record what we got.
3365: */
1.367 djm 3366: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3367: fwd->listen_port == 0 &&
1.295 djm 3368: allocated_listen_port != NULL &&
3369: *allocated_listen_port == 0) {
1.350 djm 3370: *allocated_listen_port = get_local_port(sock);
1.295 djm 3371: debug("Allocated listen port %d",
3372: *allocated_listen_port);
3373: }
3374:
1.35 markus 3375: /* Allocate a channel number for the socket. */
1.367 djm 3376: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3377: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3378: 0, "port listener", 1);
1.293 djm 3379: c->path = xstrdup(host);
1.336 millert 3380: c->host_port = fwd->connect_port;
1.312 djm 3381: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3382: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 3383: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
3384: c->listening_port = *allocated_listen_port;
3385: else
1.336 millert 3386: c->listening_port = fwd->listen_port;
1.35 markus 3387: success = 1;
3388: }
3389: if (success == 0)
1.336 millert 3390: error("%s: cannot listen to port: %d", __func__,
3391: fwd->listen_port);
1.35 markus 3392: freeaddrinfo(aitop);
1.87 markus 3393: return success;
1.25 markus 3394: }
1.1 deraadt 3395:
1.336 millert 3396: static int
1.367 djm 3397: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3398: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3399: {
3400: struct sockaddr_un sunaddr;
3401: const char *path;
3402: Channel *c;
3403: int port, sock;
3404: mode_t omask;
3405:
3406: switch (type) {
3407: case SSH_CHANNEL_UNIX_LISTENER:
3408: if (fwd->connect_path != NULL) {
3409: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3410: error("Local connecting path too long: %s",
3411: fwd->connect_path);
3412: return 0;
3413: }
3414: path = fwd->connect_path;
3415: port = PORT_STREAMLOCAL;
3416: } else {
3417: if (fwd->connect_host == NULL) {
3418: error("No forward host name.");
3419: return 0;
3420: }
3421: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3422: error("Forward host name too long.");
3423: return 0;
3424: }
3425: path = fwd->connect_host;
3426: port = fwd->connect_port;
3427: }
3428: break;
3429: case SSH_CHANNEL_RUNIX_LISTENER:
3430: path = fwd->listen_path;
3431: port = PORT_STREAMLOCAL;
3432: break;
3433: default:
3434: error("%s: unexpected channel type %d", __func__, type);
3435: return 0;
3436: }
3437:
3438: if (fwd->listen_path == NULL) {
3439: error("No forward path name.");
3440: return 0;
3441: }
3442: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3443: error("Local listening path too long: %s", fwd->listen_path);
3444: return 0;
3445: }
3446:
3447: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
3448:
3449: /* Start a Unix domain listener. */
3450: omask = umask(fwd_opts->streamlocal_bind_mask);
3451: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3452: fwd_opts->streamlocal_bind_unlink);
3453: umask(omask);
3454: if (sock < 0)
3455: return 0;
3456:
3457: debug("Local forwarding listening on path %s.", fwd->listen_path);
3458:
3459: /* Allocate a channel number for the socket. */
1.367 djm 3460: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3461: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3462: 0, "unix listener", 1);
3463: c->path = xstrdup(path);
3464: c->host_port = port;
3465: c->listening_port = PORT_STREAMLOCAL;
3466: c->listening_addr = xstrdup(fwd->listen_path);
3467: return 1;
3468: }
3469:
3470: static int
1.367 djm 3471: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3472: const char *host, u_short port)
1.202 djm 3473: {
1.209 avsm 3474: u_int i;
3475: int found = 0;
1.202 djm 3476:
1.367 djm 3477: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3478: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3479: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3480: continue;
3481: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3482: debug2("%s: close channel %d", __func__, i);
1.367 djm 3483: channel_free(ssh, c);
1.312 djm 3484: found = 1;
3485: }
3486: }
3487:
1.367 djm 3488: return found;
1.312 djm 3489: }
3490:
1.336 millert 3491: static int
1.367 djm 3492: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3493: {
3494: u_int i;
3495: int found = 0;
3496:
1.367 djm 3497: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3498: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3499: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3500: continue;
3501: if (c->path == NULL)
3502: continue;
3503: if (strcmp(c->path, path) == 0) {
3504: debug2("%s: close channel %d", __func__, i);
1.367 djm 3505: channel_free(ssh, c);
1.336 millert 3506: found = 1;
3507: }
3508: }
3509:
1.367 djm 3510: return found;
1.336 millert 3511: }
3512:
1.312 djm 3513: int
1.367 djm 3514: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3515: {
1.367 djm 3516: if (fwd->listen_path != NULL) {
3517: return channel_cancel_rport_listener_streamlocal(ssh,
3518: fwd->listen_path);
3519: } else {
3520: return channel_cancel_rport_listener_tcpip(ssh,
3521: fwd->listen_host, fwd->listen_port);
3522: }
1.336 millert 3523: }
3524:
3525: static int
1.367 djm 3526: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3527: const char *lhost, u_short lport, int cport,
3528: struct ForwardOptions *fwd_opts)
1.312 djm 3529: {
3530: u_int i;
3531: int found = 0;
1.336 millert 3532: const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts);
1.202 djm 3533:
1.367 djm 3534: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3535: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3536: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3537: continue;
1.313 markus 3538: if (c->listening_port != lport)
1.312 djm 3539: continue;
1.313 markus 3540: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3541: /* skip dynamic forwardings */
3542: if (c->host_port == 0)
3543: continue;
3544: } else {
3545: if (c->host_port != cport)
3546: continue;
3547: }
1.312 djm 3548: if ((c->listening_addr == NULL && addr != NULL) ||
3549: (c->listening_addr != NULL && addr == NULL))
3550: continue;
3551: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3552: debug2("%s: close channel %d", __func__, i);
1.367 djm 3553: channel_free(ssh, c);
1.202 djm 3554: found = 1;
3555: }
3556: }
3557:
1.367 djm 3558: return found;
1.202 djm 3559: }
3560:
1.336 millert 3561: static int
1.367 djm 3562: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3563: {
3564: u_int i;
3565: int found = 0;
3566:
3567: if (path == NULL) {
3568: error("%s: no path specified.", __func__);
3569: return 0;
3570: }
3571:
1.367 djm 3572: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3573: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3574: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3575: continue;
3576: if (c->listening_addr == NULL)
3577: continue;
3578: if (strcmp(c->listening_addr, path) == 0) {
3579: debug2("%s: close channel %d", __func__, i);
1.367 djm 3580: channel_free(ssh, c);
1.336 millert 3581: found = 1;
3582: }
3583: }
3584:
1.367 djm 3585: return found;
1.336 millert 3586: }
3587:
3588: int
1.367 djm 3589: channel_cancel_lport_listener(struct ssh *ssh,
3590: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3591: {
1.367 djm 3592: if (fwd->listen_path != NULL) {
3593: return channel_cancel_lport_listener_streamlocal(ssh,
3594: fwd->listen_path);
3595: } else {
3596: return channel_cancel_lport_listener_tcpip(ssh,
3597: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3598: }
1.336 millert 3599: }
3600:
1.362 markus 3601: /* protocol local port fwd, used by ssh */
1.160 markus 3602: int
1.367 djm 3603: channel_setup_local_fwd_listener(struct ssh *ssh,
3604: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3605: {
1.336 millert 3606: if (fwd->listen_path != NULL) {
1.367 djm 3607: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3608: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3609: } else {
1.367 djm 3610: return channel_setup_fwd_listener_tcpip(ssh,
3611: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3612: }
1.160 markus 3613: }
3614:
3615: /* protocol v2 remote port fwd, used by sshd */
3616: int
1.367 djm 3617: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3618: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3619: {
1.336 millert 3620: if (fwd->listen_path != NULL) {
1.367 djm 3621: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3622: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3623: } else {
1.367 djm 3624: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 3625: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3626: fwd_opts);
3627: }
1.160 markus 3628: }
3629:
1.27 markus 3630: /*
1.312 djm 3631: * Translate the requested rfwd listen host to something usable for
3632: * this server.
3633: */
3634: static const char *
3635: channel_rfwd_bind_host(const char *listen_host)
3636: {
3637: if (listen_host == NULL) {
3638: if (datafellows & SSH_BUG_RFWD_ADDR)
3639: return "127.0.0.1";
3640: else
3641: return "localhost";
3642: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
3643: if (datafellows & SSH_BUG_RFWD_ADDR)
3644: return "0.0.0.0";
3645: else
3646: return "";
3647: } else
3648: return listen_host;
3649: }
3650:
3651: /*
1.27 markus 3652: * Initiate forwarding of connections to port "port" on remote host through
3653: * the secure channel to host:port from local side.
1.315 markus 3654: * Returns handle (index) for updating the dynamic listen port with
3655: * channel_update_permitted_opens().
1.27 markus 3656: */
1.253 markus 3657: int
1.367 djm 3658: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 3659: {
1.367 djm 3660: int r, success = 0, idx = -1;
3661: char *host_to_connect, *listen_host, *listen_path;
3662: int port_to_connect, listen_port;
1.73 markus 3663:
1.25 markus 3664: /* Send the forward request to the remote side. */
1.358 djm 3665: if (fwd->listen_path != NULL) {
1.367 djm 3666: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3667: (r = sshpkt_put_cstring(ssh,
3668: "streamlocal-forward@openssh.com")) != 0 ||
3669: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3670: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3671: (r = sshpkt_send(ssh)) != 0 ||
3672: (r = ssh_packet_write_wait(ssh)) != 0)
3673: fatal("%s: request streamlocal: %s",
3674: __func__, ssh_err(r));
1.336 millert 3675: } else {
1.367 djm 3676: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3677: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
3678: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3679: (r = sshpkt_put_cstring(ssh,
3680: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
3681: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
3682: (r = sshpkt_send(ssh)) != 0 ||
3683: (r = ssh_packet_write_wait(ssh)) != 0)
3684: fatal("%s: request tcpip-forward: %s",
3685: __func__, ssh_err(r));
1.73 markus 3686: }
1.358 djm 3687: /* Assume that server accepts the request */
3688: success = 1;
1.73 markus 3689: if (success) {
1.305 djm 3690: /* Record that connection to this host/port is permitted. */
1.367 djm 3691: host_to_connect = listen_host = listen_path = NULL;
3692: port_to_connect = listen_port = 0;
1.336 millert 3693: if (fwd->connect_path != NULL) {
1.367 djm 3694: host_to_connect = xstrdup(fwd->connect_path);
3695: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 3696: } else {
1.367 djm 3697: host_to_connect = xstrdup(fwd->connect_host);
3698: port_to_connect = fwd->connect_port;
1.336 millert 3699: }
3700: if (fwd->listen_path != NULL) {
1.367 djm 3701: listen_path = xstrdup(fwd->listen_path);
3702: listen_port = PORT_STREAMLOCAL;
1.336 millert 3703: } else {
1.367 djm 3704: if (fwd->listen_host != NULL)
3705: listen_host = xstrdup(fwd->listen_host);
3706: listen_port = fwd->listen_port;
3707: }
3708: idx = fwd_perm_list_add(ssh, FWDPERM_USER,
3709: host_to_connect, port_to_connect,
3710: listen_host, listen_path, listen_port, NULL);
1.44 markus 3711: }
1.367 djm 3712: return idx;
1.1 deraadt 3713: }
3714:
1.333 markus 3715: static int
3716: open_match(ForwardPermission *allowed_open, const char *requestedhost,
1.336 millert 3717: int requestedport)
1.333 markus 3718: {
3719: if (allowed_open->host_to_connect == NULL)
3720: return 0;
3721: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3722: allowed_open->port_to_connect != requestedport)
3723: return 0;
1.351 dtucker 3724: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3725: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3726: return 0;
3727: return 1;
3728: }
3729:
3730: /*
1.336 millert 3731: * Note that in the listen host/port case
1.333 markus 3732: * we don't support FWD_PERMIT_ANY_PORT and
3733: * need to translate between the configured-host (listen_host)
3734: * and what we've sent to the remote server (channel_rfwd_bind_host)
3735: */
3736: static int
1.336 millert 3737: open_listen_match_tcpip(ForwardPermission *allowed_open,
3738: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3739: {
3740: const char *allowed_host;
3741:
3742: if (allowed_open->host_to_connect == NULL)
3743: return 0;
3744: if (allowed_open->listen_port != requestedport)
3745: return 0;
1.335 djm 3746: if (!translate && allowed_open->listen_host == NULL &&
3747: requestedhost == NULL)
3748: return 1;
1.333 markus 3749: allowed_host = translate ?
3750: channel_rfwd_bind_host(allowed_open->listen_host) :
3751: allowed_open->listen_host;
3752: if (allowed_host == NULL ||
3753: strcmp(allowed_host, requestedhost) != 0)
3754: return 0;
3755: return 1;
3756: }
3757:
1.336 millert 3758: static int
3759: open_listen_match_streamlocal(ForwardPermission *allowed_open,
3760: const char *requestedpath)
3761: {
3762: if (allowed_open->host_to_connect == NULL)
3763: return 0;
3764: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3765: return 0;
3766: if (allowed_open->listen_path == NULL ||
3767: strcmp(allowed_open->listen_path, requestedpath) != 0)
3768: return 0;
3769: return 1;
3770: }
3771:
1.27 markus 3772: /*
1.208 deraadt 3773: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3774: * local side.
3775: */
1.336 millert 3776: static int
1.367 djm 3777: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
3778: const char *host, u_short port)
1.202 djm 3779: {
1.367 djm 3780: struct ssh_channels *sc = ssh->chanctxt;
3781: int r;
3782: u_int i;
3783: ForwardPermission *fp;
1.202 djm 3784:
1.367 djm 3785: for (i = 0; i < sc->num_permitted_opens; i++) {
3786: fp = &sc->permitted_opens[i];
3787: if (open_listen_match_tcpip(fp, host, port, 0))
1.202 djm 3788: break;
1.367 djm 3789: fp = NULL;
1.202 djm 3790: }
1.367 djm 3791: if (fp == NULL) {
1.202 djm 3792: debug("%s: requested forward not found", __func__);
1.312 djm 3793: return -1;
1.202 djm 3794: }
1.367 djm 3795: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3796: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
3797: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3798: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
3799: (r = sshpkt_put_u32(ssh, port)) != 0 ||
3800: (r = sshpkt_send(ssh)) != 0)
3801: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3802:
3803: fwd_perm_clear(fp); /* unregister */
1.336 millert 3804:
3805: return 0;
3806: }
3807:
3808: /*
3809: * Request cancellation of remote forwarding of Unix domain socket
3810: * path from local side.
3811: */
3812: static int
1.367 djm 3813: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3814: {
1.367 djm 3815: struct ssh_channels *sc = ssh->chanctxt;
3816: int r;
3817: u_int i;
3818: ForwardPermission *fp;
1.336 millert 3819:
1.367 djm 3820: for (i = 0; i < sc->num_permitted_opens; i++) {
3821: fp = &sc->permitted_opens[i];
3822: if (open_listen_match_streamlocal(fp, path))
1.336 millert 3823: break;
1.367 djm 3824: fp = NULL;
1.336 millert 3825: }
1.367 djm 3826: if (fp == NULL) {
1.336 millert 3827: debug("%s: requested forward not found", __func__);
3828: return -1;
3829: }
1.367 djm 3830: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3831: (r = sshpkt_put_cstring(ssh,
3832: "cancel-streamlocal-forward@openssh.com")) != 0 ||
3833: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3834: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
3835: (r = sshpkt_send(ssh)) != 0)
3836: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3837:
3838: fwd_perm_clear(fp); /* unregister */
1.312 djm 3839:
3840: return 0;
1.202 djm 3841: }
3842:
3843: /*
1.336 millert 3844: * Request cancellation of remote forwarding of a connection from local side.
3845: */
3846: int
1.367 djm 3847: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3848: {
3849: if (fwd->listen_path != NULL) {
1.367 djm 3850: return channel_request_rforward_cancel_streamlocal(ssh,
3851: fwd->listen_path);
1.336 millert 3852: } else {
1.367 djm 3853: return channel_request_rforward_cancel_tcpip(ssh,
3854: fwd->listen_host,
3855: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 3856: }
1.1 deraadt 3857: }
3858:
1.99 markus 3859: /*
3860: * Permits opening to any host/port if permitted_opens[] is empty. This is
3861: * usually called by the server, because the user could connect to any port
3862: * anyway, and the server has no way to know but to trust the client anyway.
3863: */
3864: void
1.367 djm 3865: channel_permit_all_opens(struct ssh *ssh)
1.99 markus 3866: {
1.367 djm 3867: if (ssh->chanctxt->num_permitted_opens == 0)
3868: ssh->chanctxt->all_opens_permitted = 1;
1.99 markus 3869: }
3870:
1.101 markus 3871: void
1.367 djm 3872: channel_add_permitted_opens(struct ssh *ssh, char *host, int port)
1.99 markus 3873: {
1.367 djm 3874: struct ssh_channels *sc = ssh->chanctxt;
3875:
1.99 markus 3876: debug("allow port forwarding to host %s port %d", host, port);
1.367 djm 3877: fwd_perm_list_add(ssh, FWDPERM_USER, host, port, NULL, NULL, 0, NULL);
3878: sc->all_opens_permitted = 0;
1.315 markus 3879: }
3880:
3881: /*
3882: * Update the listen port for a dynamic remote forward, after
3883: * the actual 'newport' has been allocated. If 'newport' < 0 is
3884: * passed then they entry will be invalidated.
3885: */
3886: void
1.367 djm 3887: channel_update_permitted_opens(struct ssh *ssh, int idx, int newport)
1.315 markus 3888: {
1.367 djm 3889: struct ssh_channels *sc = ssh->chanctxt;
3890:
3891: if (idx < 0 || (u_int)idx >= sc->num_permitted_opens) {
3892: debug("%s: index out of range: %d num_permitted_opens %d",
3893: __func__, idx, sc->num_permitted_opens);
1.315 markus 3894: return;
3895: }
3896: debug("%s allowed port %d for forwarding to host %s port %d",
3897: newport > 0 ? "Updating" : "Removing",
3898: newport,
1.367 djm 3899: sc->permitted_opens[idx].host_to_connect,
3900: sc->permitted_opens[idx].port_to_connect);
3901: if (newport <= 0)
3902: fwd_perm_clear(&sc->permitted_opens[idx]);
3903: else {
3904: sc->permitted_opens[idx].listen_port =
1.315 markus 3905: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
3906: }
1.99 markus 3907: }
3908:
1.258 dtucker 3909: int
1.367 djm 3910: channel_add_adm_permitted_opens(struct ssh *ssh, char *host, int port)
1.257 dtucker 3911: {
1.258 dtucker 3912: debug("config allows port forwarding to host %s port %d", host, port);
1.367 djm 3913: return fwd_perm_list_add(ssh, FWDPERM_ADMIN, host, port,
3914: NULL, NULL, 0, NULL);
1.316 dtucker 3915: }
3916:
3917: void
1.367 djm 3918: channel_disable_adm_local_opens(struct ssh *ssh)
1.99 markus 3919: {
1.367 djm 3920: channel_clear_adm_permitted_opens(ssh);
3921: fwd_perm_list_add(ssh, FWDPERM_ADMIN, NULL, 0, NULL, NULL, 0, NULL);
1.257 dtucker 3922: }
3923:
3924: void
1.367 djm 3925: channel_clear_permitted_opens(struct ssh *ssh)
1.257 dtucker 3926: {
1.367 djm 3927: struct ssh_channels *sc = ssh->chanctxt;
1.99 markus 3928:
1.367 djm 3929: sc->permitted_opens = xrecallocarray(sc->permitted_opens,
3930: sc->num_permitted_opens, 0, sizeof(*sc->permitted_opens));
3931: sc->num_permitted_opens = 0;
1.278 dtucker 3932: }
3933:
3934: void
1.367 djm 3935: channel_clear_adm_permitted_opens(struct ssh *ssh)
1.278 dtucker 3936: {
1.367 djm 3937: struct ssh_channels *sc = ssh->chanctxt;
1.278 dtucker 3938:
1.367 djm 3939: sc->permitted_adm_opens = xrecallocarray(sc->permitted_adm_opens,
3940: sc->num_adm_permitted_opens, 0, sizeof(*sc->permitted_adm_opens));
3941: sc->num_adm_permitted_opens = 0;
1.99 markus 3942: }
3943:
1.314 dtucker 3944: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3945: int
3946: permitopen_port(const char *p)
3947: {
3948: int port;
3949:
3950: if (strcmp(p, "*") == 0)
3951: return FWD_PERMIT_ANY_PORT;
3952: if ((port = a2port(p)) > 0)
3953: return port;
3954: return -1;
3955: }
3956:
1.276 djm 3957: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 3958: static int
1.276 djm 3959: connect_next(struct channel_connect *cctx)
1.41 markus 3960: {
1.276 djm 3961: int sock, saved_errno;
1.336 millert 3962: struct sockaddr_un *sunaddr;
1.367 djm 3963: char ntop[NI_MAXHOST];
3964: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 3965:
1.276 djm 3966: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 3967: switch (cctx->ai->ai_family) {
3968: case AF_UNIX:
3969: /* unix:pathname instead of host:port */
3970: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
3971: strlcpy(ntop, "unix", sizeof(ntop));
3972: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
3973: break;
3974: case AF_INET:
3975: case AF_INET6:
3976: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
3977: ntop, sizeof(ntop), strport, sizeof(strport),
3978: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
3979: error("connect_next: getnameinfo failed");
3980: continue;
3981: }
3982: break;
3983: default:
1.41 markus 3984: continue;
3985: }
1.300 dtucker 3986: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
3987: cctx->ai->ai_protocol)) == -1) {
1.276 djm 3988: if (cctx->ai->ai_next == NULL)
1.186 djm 3989: error("socket: %.100s", strerror(errno));
3990: else
3991: verbose("socket: %.100s", strerror(errno));
1.41 markus 3992: continue;
3993: }
1.205 djm 3994: if (set_nonblock(sock) == -1)
3995: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 3996: if (connect(sock, cctx->ai->ai_addr,
3997: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
3998: debug("connect_next: host %.100s ([%.100s]:%s): "
3999: "%.100s", cctx->host, ntop, strport,
1.41 markus 4000: strerror(errno));
1.276 djm 4001: saved_errno = errno;
1.41 markus 4002: close(sock);
1.276 djm 4003: errno = saved_errno;
1.89 stevesk 4004: continue; /* fail -- try next */
1.41 markus 4005: }
1.336 millert 4006: if (cctx->ai->ai_family != AF_UNIX)
4007: set_nodelay(sock);
1.276 djm 4008: debug("connect_next: host %.100s ([%.100s]:%s) "
4009: "in progress, fd=%d", cctx->host, ntop, strport, sock);
4010: cctx->ai = cctx->ai->ai_next;
4011: return sock;
4012: }
4013: return -1;
4014: }
1.41 markus 4015:
1.276 djm 4016: static void
4017: channel_connect_ctx_free(struct channel_connect *cctx)
4018: {
1.321 djm 4019: free(cctx->host);
1.336 millert 4020: if (cctx->aitop) {
4021: if (cctx->aitop->ai_family == AF_UNIX)
4022: free(cctx->aitop);
4023: else
4024: freeaddrinfo(cctx->aitop);
4025: }
1.329 tedu 4026: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4027: }
4028:
1.357 dtucker 4029: /*
1.372 markus 4030: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4031: * passing back the failure reason if appropriate.
4032: */
1.372 markus 4033: static int
4034: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4035: char *ctype, char *rname, struct channel_connect *cctx,
4036: int *reason, const char **errmsg)
1.276 djm 4037: {
4038: struct addrinfo hints;
4039: int gaierr;
4040: int sock = -1;
4041: char strport[NI_MAXSERV];
1.336 millert 4042:
4043: if (port == PORT_STREAMLOCAL) {
4044: struct sockaddr_un *sunaddr;
4045: struct addrinfo *ai;
4046:
4047: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4048: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4049: return -1;
1.336 millert 4050: }
4051:
4052: /*
4053: * Fake up a struct addrinfo for AF_UNIX connections.
4054: * channel_connect_ctx_free() must check ai_family
4055: * and use free() not freeaddirinfo() for AF_UNIX.
4056: */
4057: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4058: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4059: ai->ai_addr = (struct sockaddr *)(ai + 1);
4060: ai->ai_addrlen = sizeof(*sunaddr);
4061: ai->ai_family = AF_UNIX;
1.372 markus 4062: ai->ai_socktype = socktype;
1.336 millert 4063: ai->ai_protocol = PF_UNSPEC;
4064: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4065: sunaddr->sun_family = AF_UNIX;
4066: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4067: cctx->aitop = ai;
1.336 millert 4068: } else {
4069: memset(&hints, 0, sizeof(hints));
1.367 djm 4070: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4071: hints.ai_socktype = socktype;
1.336 millert 4072: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4073: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4074: != 0) {
4075: if (errmsg != NULL)
4076: *errmsg = ssh_gai_strerror(gaierr);
4077: if (reason != NULL)
4078: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4079: error("connect_to %.100s: unknown host (%s)", name,
4080: ssh_gai_strerror(gaierr));
1.372 markus 4081: return -1;
1.336 millert 4082: }
1.41 markus 4083: }
1.276 djm 4084:
1.372 markus 4085: cctx->host = xstrdup(name);
4086: cctx->port = port;
4087: cctx->ai = cctx->aitop;
1.276 djm 4088:
1.372 markus 4089: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4090: error("connect to %.100s port %d failed: %s",
1.336 millert 4091: name, port, strerror(errno));
1.372 markus 4092: return -1;
4093: }
4094:
4095: return sock;
4096: }
4097:
4098: /* Return CONNECTING channel to remote host:port or local socket path */
4099: static Channel *
4100: connect_to(struct ssh *ssh, const char *host, int port,
4101: char *ctype, char *rname)
4102: {
4103: struct channel_connect cctx;
4104: Channel *c;
4105: int sock;
4106:
4107: memset(&cctx, 0, sizeof(cctx));
4108: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4109: &cctx, NULL, NULL);
4110: if (sock == -1) {
1.276 djm 4111: channel_connect_ctx_free(&cctx);
4112: return NULL;
1.41 markus 4113: }
1.367 djm 4114: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4115: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4116: c->host_port = port;
4117: c->path = xstrdup(host);
1.276 djm 4118: c->connect_ctx = cctx;
1.372 markus 4119:
1.276 djm 4120: return c;
1.41 markus 4121: }
1.99 markus 4122:
1.354 markus 4123: /*
4124: * returns either the newly connected channel or the downstream channel
4125: * that needs to deal with this connection.
4126: */
1.276 djm 4127: Channel *
1.367 djm 4128: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4129: u_short listen_port, char *ctype, char *rname)
1.73 markus 4130: {
1.367 djm 4131: struct ssh_channels *sc = ssh->chanctxt;
4132: u_int i;
4133: ForwardPermission *fp;
1.99 markus 4134:
1.367 djm 4135: for (i = 0; i < sc->num_permitted_opens; i++) {
4136: fp = &sc->permitted_opens[i];
4137: if (open_listen_match_tcpip(fp, listen_host, listen_port, 1)) {
4138: if (fp->downstream)
4139: return fp->downstream;
1.372 markus 4140: if (fp->port_to_connect == 0)
4141: return rdynamic_connect_prepare(ssh,
4142: ctype, rname);
1.367 djm 4143: return connect_to(ssh,
4144: fp->host_to_connect, fp->port_to_connect,
4145: ctype, rname);
1.276 djm 4146: }
4147: }
1.74 markus 4148: error("WARNING: Server requests forwarding for unknown listen_port %d",
4149: listen_port);
1.276 djm 4150: return NULL;
1.73 markus 4151: }
4152:
1.336 millert 4153: Channel *
1.367 djm 4154: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4155: char *ctype, char *rname)
1.336 millert 4156: {
1.367 djm 4157: struct ssh_channels *sc = ssh->chanctxt;
4158: u_int i;
4159: ForwardPermission *fp;
1.336 millert 4160:
1.367 djm 4161: for (i = 0; i < sc->num_permitted_opens; i++) {
4162: fp = &sc->permitted_opens[i];
4163: if (open_listen_match_streamlocal(fp, path)) {
4164: return connect_to(ssh,
4165: fp->host_to_connect, fp->port_to_connect,
4166: ctype, rname);
1.336 millert 4167: }
4168: }
4169: error("WARNING: Server requests forwarding for unknown path %.100s",
4170: path);
4171: return NULL;
4172: }
4173:
1.99 markus 4174: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4175: Channel *
1.367 djm 4176: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4177: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4178: {
1.367 djm 4179: struct ssh_channels *sc = ssh->chanctxt;
1.372 markus 4180: struct channel_connect cctx;
4181: Channel *c;
1.367 djm 4182: u_int i, permit, permit_adm = 1;
1.372 markus 4183: int sock;
1.367 djm 4184: ForwardPermission *fp;
1.99 markus 4185:
1.367 djm 4186: permit = sc->all_opens_permitted;
1.99 markus 4187: if (!permit) {
1.367 djm 4188: for (i = 0; i < sc->num_permitted_opens; i++) {
4189: fp = &sc->permitted_opens[i];
4190: if (open_match(fp, host, port)) {
1.99 markus 4191: permit = 1;
1.333 markus 4192: break;
4193: }
1.367 djm 4194: }
1.257 dtucker 4195: }
1.99 markus 4196:
1.367 djm 4197: if (sc->num_adm_permitted_opens > 0) {
1.257 dtucker 4198: permit_adm = 0;
1.367 djm 4199: for (i = 0; i < sc->num_adm_permitted_opens; i++) {
4200: fp = &sc->permitted_adm_opens[i];
4201: if (open_match(fp, host, port)) {
1.257 dtucker 4202: permit_adm = 1;
1.333 markus 4203: break;
4204: }
1.367 djm 4205: }
1.99 markus 4206: }
1.257 dtucker 4207:
4208: if (!permit || !permit_adm) {
1.188 itojun 4209: logit("Received request to connect to host %.100s port %d, "
1.99 markus 4210: "but the request was denied.", host, port);
1.357 dtucker 4211: if (reason != NULL)
4212: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4213: return NULL;
1.99 markus 4214: }
1.372 markus 4215:
4216: memset(&cctx, 0, sizeof(cctx));
4217: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4218: &cctx, reason, errmsg);
4219: if (sock == -1) {
4220: channel_connect_ctx_free(&cctx);
4221: return NULL;
4222: }
4223:
4224: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4225: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4226: c->host_port = port;
4227: c->path = xstrdup(host);
4228: c->connect_ctx = cctx;
4229:
4230: return c;
1.336 millert 4231: }
4232:
4233: /* Check if connecting to that path is permitted and connect. */
4234: Channel *
1.367 djm 4235: channel_connect_to_path(struct ssh *ssh, const char *path,
4236: char *ctype, char *rname)
1.336 millert 4237: {
1.367 djm 4238: struct ssh_channels *sc = ssh->chanctxt;
4239: u_int i, permit, permit_adm = 1;
4240: ForwardPermission *fp;
1.336 millert 4241:
1.367 djm 4242: permit = sc->all_opens_permitted;
1.336 millert 4243: if (!permit) {
1.367 djm 4244: for (i = 0; i < sc->num_permitted_opens; i++) {
4245: fp = &sc->permitted_opens[i];
4246: if (open_match(fp, path, PORT_STREAMLOCAL)) {
1.336 millert 4247: permit = 1;
4248: break;
4249: }
1.367 djm 4250: }
1.336 millert 4251: }
4252:
1.367 djm 4253: if (sc->num_adm_permitted_opens > 0) {
1.336 millert 4254: permit_adm = 0;
1.367 djm 4255: for (i = 0; i < sc->num_adm_permitted_opens; i++) {
4256: fp = &sc->permitted_adm_opens[i];
4257: if (open_match(fp, path, PORT_STREAMLOCAL)) {
1.336 millert 4258: permit_adm = 1;
4259: break;
4260: }
1.367 djm 4261: }
1.336 millert 4262: }
4263:
4264: if (!permit || !permit_adm) {
4265: logit("Received request to connect to path %.100s, "
4266: "but the request was denied.", path);
4267: return NULL;
4268: }
1.367 djm 4269: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4270: }
4271:
4272: void
1.367 djm 4273: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4274: {
1.367 djm 4275: struct ssh_channels *sc = ssh->chanctxt;
4276: struct winsize ws;
4277: int r;
1.209 avsm 4278: u_int i;
1.204 djm 4279:
1.367 djm 4280: for (i = 0; i < sc->channels_alloc; i++) {
4281: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4282: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4283: continue;
1.367 djm 4284: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
1.204 djm 4285: continue;
1.367 djm 4286: channel_request_start(ssh, i, "window-change", 0);
4287: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4288: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4289: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4290: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4291: (r = sshpkt_send(ssh)) != 0)
4292: fatal("%s: channel %u: send window-change: %s",
4293: __func__, i, ssh_err(r));
1.204 djm 4294: }
1.372 markus 4295: }
4296:
4297: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4298: static Channel *
4299: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4300: {
4301: Channel *c;
4302: int r;
4303:
4304: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4305: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4306: c->host_port = 0;
4307: c->path = NULL;
4308:
4309: /*
4310: * We need to open the channel before we have a FD,
4311: * so that we can get SOCKS header from peer.
4312: */
4313: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4314: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4315: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4316: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
4317: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
4318: fatal("%s: channel %i: confirm: %s", __func__,
4319: c->self, ssh_err(r));
4320: }
4321: return c;
4322: }
4323:
4324: /* Return CONNECTING socket to remote host:port or local socket path */
4325: static int
4326: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4327: {
4328: struct channel_connect cctx;
4329: int sock;
4330:
4331: memset(&cctx, 0, sizeof(cctx));
4332: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4333: NULL, &cctx, NULL, NULL);
4334: if (sock == -1)
4335: channel_connect_ctx_free(&cctx);
4336: else {
4337: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4338: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4339: c->connect_ctx = cctx;
4340: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4341: }
4342: return sock;
1.99 markus 4343: }
4344:
1.121 markus 4345: /* -- X11 forwarding */
1.1 deraadt 4346:
1.27 markus 4347: /*
4348: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4349: * Returns 0 and a suitable display number for the DISPLAY variable
4350: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4351: */
1.141 stevesk 4352: int
1.367 djm 4353: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4354: int x11_use_localhost, int single_connection,
4355: u_int *display_numberp, int **chanids)
1.1 deraadt 4356: {
1.149 markus 4357: Channel *nc = NULL;
1.31 markus 4358: int display_number, sock;
4359: u_short port;
1.35 markus 4360: struct addrinfo hints, *ai, *aitop;
4361: char strport[NI_MAXSERV];
4362: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4363:
1.224 markus 4364: if (chanids == NULL)
4365: return -1;
4366:
1.33 markus 4367: for (display_number = x11_display_offset;
1.148 deraadt 4368: display_number < MAX_DISPLAYS;
4369: display_number++) {
1.25 markus 4370: port = 6000 + display_number;
1.35 markus 4371: memset(&hints, 0, sizeof(hints));
1.367 djm 4372: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4373: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4374: hints.ai_socktype = SOCK_STREAM;
4375: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4376: if ((gaierr = getaddrinfo(NULL, strport,
4377: &hints, &aitop)) != 0) {
1.271 dtucker 4378: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4379: return -1;
1.25 markus 4380: }
1.35 markus 4381: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4382: if (ai->ai_family != AF_INET &&
4383: ai->ai_family != AF_INET6)
1.35 markus 4384: continue;
1.300 dtucker 4385: sock = socket(ai->ai_family, ai->ai_socktype,
4386: ai->ai_protocol);
1.35 markus 4387: if (sock < 0) {
4388: error("socket: %.100s", strerror(errno));
1.203 markus 4389: freeaddrinfo(aitop);
1.141 stevesk 4390: return -1;
1.35 markus 4391: }
1.226 djm 4392: channel_set_reuseaddr(sock);
1.35 markus 4393: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.367 djm 4394: debug2("%s: bind port %d: %.100s", __func__,
4395: port, strerror(errno));
1.35 markus 4396: close(sock);
1.367 djm 4397: for (n = 0; n < num_socks; n++)
1.35 markus 4398: close(socks[n]);
4399: num_socks = 0;
4400: break;
4401: }
4402: socks[num_socks++] = sock;
4403: if (num_socks == NUM_SOCKS)
4404: break;
1.25 markus 4405: }
1.83 stevesk 4406: freeaddrinfo(aitop);
1.35 markus 4407: if (num_socks > 0)
4408: break;
1.25 markus 4409: }
4410: if (display_number >= MAX_DISPLAYS) {
4411: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4412: return -1;
1.25 markus 4413: }
4414: /* Start listening for connections on the socket. */
1.35 markus 4415: for (n = 0; n < num_socks; n++) {
4416: sock = socks[n];
1.199 markus 4417: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 4418: error("listen: %.100s", strerror(errno));
4419: close(sock);
1.141 stevesk 4420: return -1;
1.35 markus 4421: }
1.25 markus 4422: }
1.35 markus 4423:
4424: /* Allocate a channel for each socket. */
1.242 djm 4425: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4426: for (n = 0; n < num_socks; n++) {
4427: sock = socks[n];
1.367 djm 4428: nc = channel_new(ssh, "x11 listener",
1.51 markus 4429: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4430: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4431: 0, "X11 inet listener", 1);
1.167 markus 4432: nc->single_connection = single_connection;
1.224 markus 4433: (*chanids)[n] = nc->self;
1.35 markus 4434: }
1.224 markus 4435: (*chanids)[n] = -1;
1.1 deraadt 4436:
1.141 stevesk 4437: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4438: *display_numberp = display_number;
1.367 djm 4439: return 0;
1.1 deraadt 4440: }
4441:
1.127 itojun 4442: static int
1.77 markus 4443: connect_local_xsocket(u_int dnr)
1.1 deraadt 4444: {
1.25 markus 4445: int sock;
4446: struct sockaddr_un addr;
4447:
1.147 stevesk 4448: sock = socket(AF_UNIX, SOCK_STREAM, 0);
4449: if (sock < 0)
4450: error("socket: %.100s", strerror(errno));
4451: memset(&addr, 0, sizeof(addr));
4452: addr.sun_family = AF_UNIX;
4453: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4454: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4455: return sock;
4456: close(sock);
1.25 markus 4457: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4458: return -1;
1.1 deraadt 4459: }
4460:
1.51 markus 4461: int
1.367 djm 4462: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4463: {
1.248 deraadt 4464: u_int display_number;
1.25 markus 4465: const char *display;
1.51 markus 4466: char buf[1024], *cp;
1.35 markus 4467: struct addrinfo hints, *ai, *aitop;
4468: char strport[NI_MAXSERV];
1.248 deraadt 4469: int gaierr, sock = 0;
1.25 markus 4470:
4471: /* Try to open a socket for the local X server. */
4472: display = getenv("DISPLAY");
4473: if (!display) {
4474: error("DISPLAY not set.");
1.51 markus 4475: return -1;
1.25 markus 4476: }
1.27 markus 4477: /*
4478: * Now we decode the value of the DISPLAY variable and make a
4479: * connection to the real X server.
4480: */
4481:
4482: /*
4483: * Check if it is a unix domain socket. Unix domain displays are in
4484: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4485: */
1.25 markus 4486: if (strncmp(display, "unix:", 5) == 0 ||
4487: display[0] == ':') {
4488: /* Connect to the unix domain socket. */
1.367 djm 4489: if (sscanf(strrchr(display, ':') + 1, "%u",
4490: &display_number) != 1) {
4491: error("Could not parse display number from DISPLAY: "
4492: "%.100s", display);
1.51 markus 4493: return -1;
1.25 markus 4494: }
4495: /* Create a socket. */
4496: sock = connect_local_xsocket(display_number);
4497: if (sock < 0)
1.51 markus 4498: return -1;
1.25 markus 4499:
4500: /* OK, we now have a connection to the display. */
1.51 markus 4501: return sock;
1.25 markus 4502: }
1.27 markus 4503: /*
4504: * Connect to an inet socket. The DISPLAY value is supposedly
4505: * hostname:d[.s], where hostname may also be numeric IP address.
4506: */
1.145 stevesk 4507: strlcpy(buf, display, sizeof(buf));
1.25 markus 4508: cp = strchr(buf, ':');
4509: if (!cp) {
4510: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4511: return -1;
1.25 markus 4512: }
4513: *cp = 0;
1.367 djm 4514: /*
4515: * buf now contains the host name. But first we parse the
4516: * display number.
4517: */
1.248 deraadt 4518: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4519: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4520: display);
1.51 markus 4521: return -1;
1.25 markus 4522: }
1.35 markus 4523:
4524: /* Look up the host address */
4525: memset(&hints, 0, sizeof(hints));
1.367 djm 4526: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4527: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4528: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4529: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4530: error("%.100s: unknown host. (%s)", buf,
4531: ssh_gai_strerror(gaierr));
1.51 markus 4532: return -1;
1.25 markus 4533: }
1.35 markus 4534: for (ai = aitop; ai; ai = ai->ai_next) {
4535: /* Create a socket. */
1.300 dtucker 4536: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 4537: if (sock < 0) {
1.194 markus 4538: debug2("socket: %.100s", strerror(errno));
1.41 markus 4539: continue;
4540: }
4541: /* Connect it to the display. */
4542: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 4543: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4544: 6000 + display_number, strerror(errno));
4545: close(sock);
4546: continue;
4547: }
4548: /* Success */
4549: break;
1.35 markus 4550: }
4551: freeaddrinfo(aitop);
4552: if (!ai) {
1.367 djm 4553: error("connect %.100s port %u: %.100s", buf,
4554: 6000 + display_number, strerror(errno));
1.51 markus 4555: return -1;
1.25 markus 4556: }
1.162 stevesk 4557: set_nodelay(sock);
1.51 markus 4558: return sock;
4559: }
4560:
4561: /*
1.27 markus 4562: * Requests forwarding of X11 connections, generates fake authentication
4563: * data, and enables authentication spoofing.
1.121 markus 4564: * This should be called in the client only.
1.27 markus 4565: */
1.49 markus 4566: void
1.367 djm 4567: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4568: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4569: {
1.367 djm 4570: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4571: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4572: u_int i, value;
1.367 djm 4573: const char *cp;
1.25 markus 4574: char *new_data;
1.367 djm 4575: int r, screen_number;
1.25 markus 4576:
1.367 djm 4577: if (sc->x11_saved_display == NULL)
4578: sc->x11_saved_display = xstrdup(disp);
4579: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4580: error("x11_request_forwarding_with_spoofing: different "
4581: "$DISPLAY already forwarded");
4582: return;
4583: }
4584:
1.266 djm 4585: cp = strchr(disp, ':');
1.25 markus 4586: if (cp)
4587: cp = strchr(cp, '.');
4588: if (cp)
1.245 deraadt 4589: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4590: else
4591: screen_number = 0;
4592:
1.367 djm 4593: if (sc->x11_saved_proto == NULL) {
1.219 djm 4594: /* Save protocol name. */
1.367 djm 4595: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4596:
4597: /* Extract real authentication data. */
1.367 djm 4598: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4599: for (i = 0; i < data_len; i++) {
4600: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4601: fatal("x11_request_forwarding: bad "
4602: "authentication data: %.100s", data);
1.367 djm 4603: sc->x11_saved_data[i] = value;
1.219 djm 4604: }
1.367 djm 4605: sc->x11_saved_data_len = data_len;
1.353 natano 4606:
4607: /* Generate fake data of the same length. */
1.367 djm 4608: sc->x11_fake_data = xmalloc(data_len);
4609: arc4random_buf(sc->x11_fake_data, data_len);
4610: sc->x11_fake_data_len = data_len;
1.25 markus 4611: }
4612:
4613: /* Convert the fake data into hex. */
1.367 djm 4614: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 4615:
4616: /* Send the request packet. */
1.367 djm 4617: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4618: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4619: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4620: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4621: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4622: (r = sshpkt_send(ssh)) != 0 ||
4623: (r = ssh_packet_write_wait(ssh)) != 0)
4624: fatal("%s: send x11-req: %s", __func__, ssh_err(r));
1.321 djm 4625: free(new_data);
1.1 deraadt 4626: }
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