Annotation of src/usr.bin/ssh/channels.c, Revision 1.378
1.378 ! djm 1: /* $OpenBSD: channels.c,v 1.377 2017/12/05 01:30:19 djm Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.336 millert 43: #include <sys/stat.h>
1.234 stevesk 44: #include <sys/ioctl.h>
1.235 stevesk 45: #include <sys/un.h>
1.251 stevesk 46: #include <sys/socket.h>
1.261 stevesk 47: #include <sys/time.h>
1.275 djm 48: #include <sys/queue.h>
1.251 stevesk 49:
50: #include <netinet/in.h>
51: #include <arpa/inet.h>
1.233 stevesk 52:
1.254 stevesk 53: #include <errno.h>
1.298 dtucker 54: #include <fcntl.h>
1.367 djm 55: #include <limits.h>
1.255 stevesk 56: #include <netdb.h>
1.367 djm 57: #include <stdarg.h>
1.341 millert 58: #include <stdint.h>
1.263 stevesk 59: #include <stdio.h>
1.262 stevesk 60: #include <stdlib.h>
1.260 stevesk 61: #include <string.h>
1.233 stevesk 62: #include <termios.h>
1.256 stevesk 63: #include <unistd.h>
1.1 deraadt 64:
1.265 deraadt 65: #include "xmalloc.h"
1.1 deraadt 66: #include "ssh.h"
1.82 markus 67: #include "ssh2.h"
1.354 markus 68: #include "ssherr.h"
1.367 djm 69: #include "sshbuf.h"
1.1 deraadt 70: #include "packet.h"
1.82 markus 71: #include "log.h"
72: #include "misc.h"
1.14 markus 73: #include "channels.h"
74: #include "compat.h"
1.82 markus 75: #include "canohost.h"
1.64 markus 76: #include "key.h"
77: #include "authfd.h"
1.147 stevesk 78: #include "pathnames.h"
1.1 deraadt 79:
1.367 djm 80: /* -- agent forwarding */
81: #define NUM_SOCKS 10
1.12 markus 82:
1.367 djm 83: /* -- tcp forwarding */
84: /* special-case port number meaning allow any port */
85: #define FWD_PERMIT_ANY_PORT 0
1.1 deraadt 86:
1.367 djm 87: /* special-case wildcard meaning allow any host */
88: #define FWD_PERMIT_ANY_HOST "*"
1.1 deraadt 89:
1.367 djm 90: /* -- X11 forwarding */
91: /* Maximum number of fake X11 displays to try. */
92: #define MAX_DISPLAYS 1000
1.1 deraadt 93:
1.27 markus 94: /*
95: * Data structure for storing which hosts are permitted for forward requests.
96: * The local sides of any remote forwards are stored in this array to prevent
97: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
98: * network (which might be behind a firewall).
99: */
1.336 millert 100: /* XXX: streamlocal wants a path instead of host:port */
101: /* Overload host_to_connect; we could just make this match Forward */
102: /* XXX - can we use listen_host instead of listen_path? */
1.25 markus 103: typedef struct {
1.41 markus 104: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 105: int port_to_connect; /* Connect to 'port'. */
1.333 markus 106: char *listen_host; /* Remote side should listen address. */
1.336 millert 107: char *listen_path; /* Remote side should listen path. */
108: int listen_port; /* Remote side should listen port. */
1.354 markus 109: Channel *downstream; /* Downstream mux*/
1.1 deraadt 110: } ForwardPermission;
111:
1.367 djm 112: typedef void chan_fn(struct ssh *, Channel *c,
113: fd_set *readset, fd_set *writeset);
1.121 markus 114:
1.367 djm 115: /* Master structure for channels state */
116: struct ssh_channels {
117: /*
118: * Pointer to an array containing all allocated channels. The array
119: * is dynamically extended as needed.
120: */
121: Channel **channels;
1.257 dtucker 122:
1.367 djm 123: /*
124: * Size of the channel array. All slots of the array must always be
125: * initialized (at least the type field); unused slots set to NULL
126: */
127: u_int channels_alloc;
1.257 dtucker 128:
1.367 djm 129: /*
130: * Maximum file descriptor value used in any of the channels. This is
131: * updated in channel_new.
132: */
133: int channel_max_fd;
1.257 dtucker 134:
1.367 djm 135: /*
136: * 'channel_pre*' are called just before select() to add any bits
137: * relevant to channels in the select bitmasks.
138: *
139: * 'channel_post*': perform any appropriate operations for
140: * channels which have events pending.
141: */
142: chan_fn **channel_pre;
143: chan_fn **channel_post;
1.314 dtucker 144:
1.367 djm 145: /* -- tcp forwarding */
1.351 dtucker 146:
1.367 djm 147: /* List of all permitted host/port pairs to connect by the user. */
148: ForwardPermission *permitted_opens;
1.1 deraadt 149:
1.367 djm 150: /* List of all permitted host/port pairs to connect by the admin. */
151: ForwardPermission *permitted_adm_opens;
1.121 markus 152:
1.367 djm 153: /*
154: * Number of permitted host/port pairs in the array permitted by
155: * the user.
156: */
157: u_int num_permitted_opens;
1.121 markus 158:
1.367 djm 159: /*
160: * Number of permitted host/port pair in the array permitted by
161: * the admin.
162: */
163: u_int num_adm_permitted_opens;
1.121 markus 164:
1.367 djm 165: /*
166: * If this is true, all opens are permitted. This is the case on
167: * the server on which we have to trust the client anyway, and the
168: * user could do anything after logging in anyway.
169: */
170: int all_opens_permitted;
1.219 djm 171:
1.367 djm 172: /* -- X11 forwarding */
1.121 markus 173:
1.367 djm 174: /* Saved X11 local (client) display. */
175: char *x11_saved_display;
1.121 markus 176:
1.367 djm 177: /* Saved X11 authentication protocol name. */
178: char *x11_saved_proto;
1.347 djm 179:
1.367 djm 180: /* Saved X11 authentication data. This is the real data. */
181: char *x11_saved_data;
182: u_int x11_saved_data_len;
1.121 markus 183:
1.367 djm 184: /* Deadline after which all X11 connections are refused */
185: u_int x11_refuse_time;
1.121 markus 186:
1.367 djm 187: /*
188: * Fake X11 authentication data. This is what the server will be
189: * sending us; we should replace any occurrences of this by the
190: * real data.
191: */
192: u_char *x11_fake_data;
193: u_int x11_fake_data_len;
1.121 markus 194:
1.367 djm 195: /* AF_UNSPEC or AF_INET or AF_INET6 */
196: int IPv4or6;
197: };
1.1 deraadt 198:
1.121 markus 199: /* helper */
1.367 djm 200: static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
1.354 markus 201: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 202:
1.276 djm 203: /* non-blocking connect helpers */
204: static int connect_next(struct channel_connect *);
205: static void channel_connect_ctx_free(struct channel_connect *);
1.372 markus 206: static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
207: static int rdynamic_connect_finish(struct ssh *, Channel *);
1.276 djm 208:
1.367 djm 209: /* Setup helper */
210: static void channel_handler_init(struct ssh_channels *sc);
211:
1.121 markus 212: /* -- channel core */
1.41 markus 213:
1.367 djm 214: void
215: channel_init_channels(struct ssh *ssh)
216: {
217: struct ssh_channels *sc;
218:
219: if ((sc = calloc(1, sizeof(*sc))) == NULL ||
220: (sc->channel_pre = calloc(SSH_CHANNEL_MAX_TYPE,
221: sizeof(*sc->channel_pre))) == NULL ||
222: (sc->channel_post = calloc(SSH_CHANNEL_MAX_TYPE,
223: sizeof(*sc->channel_post))) == NULL)
224: fatal("%s: allocation failed", __func__);
225: sc->channels_alloc = 10;
226: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
227: sc->IPv4or6 = AF_UNSPEC;
228: channel_handler_init(sc);
229:
230: ssh->chanctxt = sc;
231: }
232:
1.41 markus 233: Channel *
1.367 djm 234: channel_by_id(struct ssh *ssh, int id)
1.41 markus 235: {
236: Channel *c;
1.113 markus 237:
1.367 djm 238: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
239: logit("%s: %d: bad id", __func__, id);
1.41 markus 240: return NULL;
241: }
1.367 djm 242: c = ssh->chanctxt->channels[id];
1.113 markus 243: if (c == NULL) {
1.367 djm 244: logit("%s: %d: bad id: channel free", __func__, id);
1.41 markus 245: return NULL;
246: }
247: return c;
1.55 markus 248: }
249:
1.354 markus 250: Channel *
1.368 djm 251: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 252: {
253: Channel *c;
254: u_int i;
255:
1.367 djm 256: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
257: c = ssh->chanctxt->channels[i];
1.368 djm 258: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 259: return c;
260: }
261: return NULL;
262: }
263:
1.27 markus 264: /*
1.229 markus 265: * Returns the channel if it is allowed to receive protocol messages.
266: * Private channels, like listening sockets, may not receive messages.
267: */
268: Channel *
1.367 djm 269: channel_lookup(struct ssh *ssh, int id)
1.229 markus 270: {
271: Channel *c;
272:
1.367 djm 273: if ((c = channel_by_id(ssh, id)) == NULL)
274: return NULL;
1.229 markus 275:
1.237 deraadt 276: switch (c->type) {
1.229 markus 277: case SSH_CHANNEL_X11_OPEN:
278: case SSH_CHANNEL_LARVAL:
279: case SSH_CHANNEL_CONNECTING:
280: case SSH_CHANNEL_DYNAMIC:
1.372 markus 281: case SSH_CHANNEL_RDYNAMIC_OPEN:
282: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 283: case SSH_CHANNEL_OPENING:
284: case SSH_CHANNEL_OPEN:
1.323 dtucker 285: case SSH_CHANNEL_ABANDONED:
1.354 markus 286: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 287: return c;
1.229 markus 288: }
289: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 290: return NULL;
1.229 markus 291: }
292:
293: /*
1.55 markus 294: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 295: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 296: */
1.127 itojun 297: static void
1.367 djm 298: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 299: int extusage, int nonblock, int is_tty)
1.1 deraadt 300: {
1.367 djm 301: struct ssh_channels *sc = ssh->chanctxt;
302:
1.25 markus 303: /* Update the maximum file descriptor value. */
1.367 djm 304: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, rfd);
305: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, wfd);
306: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, efd);
1.84 markus 307:
1.298 dtucker 308: if (rfd != -1)
309: fcntl(rfd, F_SETFD, FD_CLOEXEC);
310: if (wfd != -1 && wfd != rfd)
311: fcntl(wfd, F_SETFD, FD_CLOEXEC);
312: if (efd != -1 && efd != rfd && efd != wfd)
313: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 314:
1.52 markus 315: c->rfd = rfd;
316: c->wfd = wfd;
317: c->sock = (rfd == wfd) ? rfd : -1;
318: c->efd = efd;
319: c->extended_usage = extusage;
1.71 markus 320:
1.282 dtucker 321: if ((c->isatty = is_tty) != 0)
1.194 markus 322: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 323:
1.71 markus 324: /* enable nonblocking mode */
325: if (nonblock) {
326: if (rfd != -1)
327: set_nonblock(rfd);
328: if (wfd != -1)
329: set_nonblock(wfd);
330: if (efd != -1)
331: set_nonblock(efd);
332: }
1.52 markus 333: }
334:
335: /*
336: * Allocate a new channel object and set its type and socket. This will cause
337: * remote_name to be freed.
338: */
1.113 markus 339: Channel *
1.367 djm 340: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 341: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 342: {
1.367 djm 343: struct ssh_channels *sc = ssh->chanctxt;
344: u_int i, found;
1.52 markus 345: Channel *c;
1.25 markus 346:
347: /* Try to find a free slot where to put the new channel. */
1.367 djm 348: for (i = 0; i < sc->channels_alloc; i++) {
349: if (sc->channels[i] == NULL) {
1.25 markus 350: /* Found a free slot. */
1.367 djm 351: found = i;
1.25 markus 352: break;
353: }
1.367 djm 354: }
355: if (i >= sc->channels_alloc) {
356: /*
357: * There are no free slots. Take last+1 slot and expand
358: * the array.
359: */
360: found = sc->channels_alloc;
361: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
362: fatal("%s: internal error: channels_alloc %d too big",
363: __func__, sc->channels_alloc);
364: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
365: sc->channels_alloc + 10, sizeof(*sc->channels));
366: sc->channels_alloc += 10;
367: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 368: }
1.113 markus 369: /* Initialize and return new channel. */
1.367 djm 370: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
371: if ((c->input = sshbuf_new()) == NULL ||
372: (c->output = sshbuf_new()) == NULL ||
373: (c->extended = sshbuf_new()) == NULL)
374: fatal("%s: sshbuf_new failed", __func__);
1.159 markus 375: c->ostate = CHAN_OUTPUT_OPEN;
376: c->istate = CHAN_INPUT_OPEN;
1.367 djm 377: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 378: c->self = found;
379: c->type = type;
1.41 markus 380: c->ctype = ctype;
1.51 markus 381: c->local_window = window;
382: c->local_window_max = window;
383: c->local_maxpacket = maxpack;
1.190 markus 384: c->remote_name = xstrdup(remote_name);
1.302 djm 385: c->ctl_chan = -1;
1.299 markus 386: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 387: TAILQ_INIT(&c->status_confirms);
1.25 markus 388: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 389: return c;
1.1 deraadt 390: }
1.52 markus 391:
1.367 djm 392: static void
393: channel_find_maxfd(struct ssh_channels *sc)
1.132 markus 394: {
1.209 avsm 395: u_int i;
396: int max = 0;
1.132 markus 397: Channel *c;
398:
1.367 djm 399: for (i = 0; i < sc->channels_alloc; i++) {
400: c = sc->channels[i];
1.132 markus 401: if (c != NULL) {
1.352 deraadt 402: max = MAXIMUM(max, c->rfd);
403: max = MAXIMUM(max, c->wfd);
404: max = MAXIMUM(max, c->efd);
1.132 markus 405: }
406: }
1.367 djm 407: sc->channel_max_fd = max;
1.132 markus 408: }
409:
410: int
1.367 djm 411: channel_close_fd(struct ssh *ssh, int *fdp)
1.132 markus 412: {
1.367 djm 413: struct ssh_channels *sc = ssh->chanctxt;
1.132 markus 414: int ret = 0, fd = *fdp;
415:
416: if (fd != -1) {
417: ret = close(fd);
418: *fdp = -1;
1.367 djm 419: if (fd == sc->channel_max_fd)
420: channel_find_maxfd(sc);
1.132 markus 421: }
422: return ret;
423: }
424:
1.52 markus 425: /* Close all channel fd/socket. */
1.127 itojun 426: static void
1.367 djm 427: channel_close_fds(struct ssh *ssh, Channel *c)
428: {
429: channel_close_fd(ssh, &c->sock);
430: channel_close_fd(ssh, &c->rfd);
431: channel_close_fd(ssh, &c->wfd);
432: channel_close_fd(ssh, &c->efd);
433: }
434:
435: static void
436: fwd_perm_clear(ForwardPermission *fp)
1.52 markus 437: {
1.367 djm 438: free(fp->host_to_connect);
439: free(fp->listen_host);
440: free(fp->listen_path);
441: bzero(fp, sizeof(*fp));
442: }
443:
444: enum { FWDPERM_USER, FWDPERM_ADMIN };
445:
446: static int
447: fwd_perm_list_add(struct ssh *ssh, int which,
448: const char *host_to_connect, int port_to_connect,
449: const char *listen_host, const char *listen_path, int listen_port,
450: Channel *downstream)
451: {
452: ForwardPermission **fpl;
453: u_int n, *nfpl;
454:
455: switch (which) {
456: case FWDPERM_USER:
457: fpl = &ssh->chanctxt->permitted_opens;
458: nfpl = &ssh->chanctxt->num_permitted_opens;
459: break;
460: case FWDPERM_ADMIN:
461: fpl = &ssh->chanctxt->permitted_adm_opens;
462: nfpl = &ssh->chanctxt->num_adm_permitted_opens;
463: break;
464: default:
465: fatal("%s: invalid list %d", __func__, which);
466: }
467:
468: if (*nfpl >= INT_MAX)
469: fatal("%s: overflow", __func__);
470:
471: *fpl = xrecallocarray(*fpl, *nfpl, *nfpl + 1, sizeof(**fpl));
472: n = (*nfpl)++;
473: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
474: (*fpl)[n].host_to_connect = MAYBE_DUP(host_to_connect);
475: (*fpl)[n].port_to_connect = port_to_connect;
476: (*fpl)[n].listen_host = MAYBE_DUP(listen_host);
477: (*fpl)[n].listen_path = MAYBE_DUP(listen_path);
478: (*fpl)[n].listen_port = listen_port;
479: (*fpl)[n].downstream = downstream;
480: #undef MAYBE_DUP
481: return (int)n;
482: }
483:
484: static void
485: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
486: {
487: struct ssh_channels *sc = ssh->chanctxt;
488: ForwardPermission *fp;
489: int r;
490: u_int i;
491:
492: for (i = 0; i < sc->num_permitted_opens; i++) {
493: fp = &sc->permitted_opens[i];
494: if (fp->downstream != c)
495: continue;
496:
497: /* cancel on the server, since mux client is gone */
498: debug("channel %d: cleanup remote forward for %s:%u",
499: c->self, fp->listen_host, fp->listen_port);
500: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
501: (r = sshpkt_put_cstring(ssh,
502: "cancel-tcpip-forward")) != 0 ||
503: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
504: (r = sshpkt_put_cstring(ssh,
505: channel_rfwd_bind_host(fp->listen_host))) != 0 ||
506: (r = sshpkt_put_u32(ssh, fp->listen_port)) != 0 ||
507: (r = sshpkt_send(ssh)) != 0) {
508: fatal("%s: channel %i: %s", __func__,
509: c->self, ssh_err(r));
510: }
511: fwd_perm_clear(fp); /* unregister */
512: }
1.121 markus 513: }
514:
515: /* Free the channel and close its fd/socket. */
516: void
1.367 djm 517: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 518: {
1.367 djm 519: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 520: char *s;
1.209 avsm 521: u_int i, n;
1.354 markus 522: Channel *other;
1.275 djm 523: struct channel_confirm *cc;
1.121 markus 524:
1.367 djm 525: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
526: if ((other = sc->channels[i]) == NULL)
527: continue;
528: n++;
529: /* detach from mux client and prepare for closing */
530: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
531: other->type == SSH_CHANNEL_MUX_PROXY &&
532: other->mux_ctx == c) {
533: other->mux_ctx = NULL;
534: other->type = SSH_CHANNEL_OPEN;
535: other->istate = CHAN_INPUT_CLOSED;
536: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 537: }
538: }
1.209 avsm 539: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 540: c->remote_name ? c->remote_name : "???", n);
541:
1.367 djm 542: if (c->type == SSH_CHANNEL_MUX_CLIENT)
543: mux_remove_remote_forwardings(ssh, c);
1.354 markus 544:
1.367 djm 545: s = channel_open_message(ssh);
1.194 markus 546: debug3("channel %d: status: %s", c->self, s);
1.321 djm 547: free(s);
1.121 markus 548:
1.367 djm 549: channel_close_fds(ssh, c);
550: sshbuf_free(c->input);
551: sshbuf_free(c->output);
552: sshbuf_free(c->extended);
553: c->input = c->output = c->extended = NULL;
1.321 djm 554: free(c->remote_name);
555: c->remote_name = NULL;
556: free(c->path);
557: c->path = NULL;
558: free(c->listening_addr);
559: c->listening_addr = NULL;
1.275 djm 560: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
561: if (cc->abandon_cb != NULL)
1.367 djm 562: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 563: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 564: explicit_bzero(cc, sizeof(*cc));
1.321 djm 565: free(cc);
1.275 djm 566: }
1.280 djm 567: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 568: c->filter_cleanup(ssh, c->self, c->filter_ctx);
569: sc->channels[c->self] = NULL;
1.371 millert 570: explicit_bzero(c, sizeof(*c));
1.321 djm 571: free(c);
1.121 markus 572: }
573:
574: void
1.367 djm 575: channel_free_all(struct ssh *ssh)
1.121 markus 576: {
1.209 avsm 577: u_int i;
1.121 markus 578:
1.367 djm 579: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
580: if (ssh->chanctxt->channels[i] != NULL)
581: channel_free(ssh, ssh->chanctxt->channels[i]);
1.131 markus 582: }
583:
1.121 markus 584: /*
585: * Closes the sockets/fds of all channels. This is used to close extra file
586: * descriptors after a fork.
587: */
588: void
1.367 djm 589: channel_close_all(struct ssh *ssh)
1.121 markus 590: {
1.209 avsm 591: u_int i;
1.121 markus 592:
1.367 djm 593: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
594: if (ssh->chanctxt->channels[i] != NULL)
595: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 596: }
597:
598: /*
1.131 markus 599: * Stop listening to channels.
600: */
601: void
1.367 djm 602: channel_stop_listening(struct ssh *ssh)
1.131 markus 603: {
1.209 avsm 604: u_int i;
1.131 markus 605: Channel *c;
606:
1.367 djm 607: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
608: c = ssh->chanctxt->channels[i];
1.131 markus 609: if (c != NULL) {
610: switch (c->type) {
611: case SSH_CHANNEL_AUTH_SOCKET:
612: case SSH_CHANNEL_PORT_LISTENER:
613: case SSH_CHANNEL_RPORT_LISTENER:
614: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 615: case SSH_CHANNEL_UNIX_LISTENER:
616: case SSH_CHANNEL_RUNIX_LISTENER:
1.367 djm 617: channel_close_fd(ssh, &c->sock);
618: channel_free(ssh, c);
1.131 markus 619: break;
620: }
621: }
622: }
623: }
624:
625: /*
1.121 markus 626: * Returns true if no channel has too much buffered data, and false if one or
627: * more channel is overfull.
628: */
629: int
1.367 djm 630: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 631: {
632: u_int i;
1.367 djm 633: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 634: Channel *c;
635:
1.367 djm 636: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
637: c = ssh->chanctxt->channels[i];
638: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
639: continue;
640: if (sshbuf_len(c->output) > maxsize) {
641: debug2("channel %d: big output buffer %zu > %u",
642: c->self, sshbuf_len(c->output), maxsize);
643: return 0;
1.121 markus 644: }
645: }
646: return 1;
647: }
648:
649: /* Returns true if any channel is still open. */
650: int
1.367 djm 651: channel_still_open(struct ssh *ssh)
1.121 markus 652: {
1.209 avsm 653: u_int i;
1.121 markus 654: Channel *c;
655:
1.367 djm 656: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
657: c = ssh->chanctxt->channels[i];
1.121 markus 658: if (c == NULL)
659: continue;
660: switch (c->type) {
661: case SSH_CHANNEL_X11_LISTENER:
662: case SSH_CHANNEL_PORT_LISTENER:
663: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 664: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 665: case SSH_CHANNEL_CLOSED:
666: case SSH_CHANNEL_AUTH_SOCKET:
667: case SSH_CHANNEL_DYNAMIC:
1.372 markus 668: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 669: case SSH_CHANNEL_CONNECTING:
670: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 671: case SSH_CHANNEL_ABANDONED:
1.336 millert 672: case SSH_CHANNEL_UNIX_LISTENER:
673: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 674: continue;
675: case SSH_CHANNEL_LARVAL:
676: continue;
677: case SSH_CHANNEL_OPENING:
678: case SSH_CHANNEL_OPEN:
1.372 markus 679: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 680: case SSH_CHANNEL_X11_OPEN:
1.302 djm 681: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 682: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 683: return 1;
684: default:
1.358 djm 685: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 686: /* NOTREACHED */
687: }
688: }
689: return 0;
690: }
691:
692: /* Returns the id of an open channel suitable for keepaliving */
693: int
1.367 djm 694: channel_find_open(struct ssh *ssh)
1.121 markus 695: {
1.209 avsm 696: u_int i;
1.121 markus 697: Channel *c;
698:
1.367 djm 699: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
700: c = ssh->chanctxt->channels[i];
1.368 djm 701: if (c == NULL || !c->have_remote_id)
1.121 markus 702: continue;
703: switch (c->type) {
704: case SSH_CHANNEL_CLOSED:
705: case SSH_CHANNEL_DYNAMIC:
1.372 markus 706: case SSH_CHANNEL_RDYNAMIC_OPEN:
707: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 708: case SSH_CHANNEL_X11_LISTENER:
709: case SSH_CHANNEL_PORT_LISTENER:
710: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 711: case SSH_CHANNEL_MUX_LISTENER:
712: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 713: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 714: case SSH_CHANNEL_OPENING:
715: case SSH_CHANNEL_CONNECTING:
716: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 717: case SSH_CHANNEL_ABANDONED:
1.336 millert 718: case SSH_CHANNEL_UNIX_LISTENER:
719: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 720: continue;
721: case SSH_CHANNEL_LARVAL:
722: case SSH_CHANNEL_AUTH_SOCKET:
723: case SSH_CHANNEL_OPEN:
724: case SSH_CHANNEL_X11_OPEN:
725: return i;
726: default:
1.358 djm 727: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 728: /* NOTREACHED */
729: }
730: }
731: return -1;
732: }
733:
734: /*
735: * Returns a message describing the currently open forwarded connections,
736: * suitable for sending to the client. The message contains crlf pairs for
737: * newlines.
738: */
739: char *
1.367 djm 740: channel_open_message(struct ssh *ssh)
1.121 markus 741: {
1.367 djm 742: struct sshbuf *buf;
1.121 markus 743: Channel *c;
1.209 avsm 744: u_int i;
1.367 djm 745: int r;
746: char *ret;
1.121 markus 747:
1.367 djm 748: if ((buf = sshbuf_new()) == NULL)
749: fatal("%s: sshbuf_new", __func__);
750: if ((r = sshbuf_putf(buf,
751: "The following connections are open:\r\n")) != 0)
752: fatal("%s: sshbuf_putf: %s", __func__, ssh_err(r));
753: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
754: c = ssh->chanctxt->channels[i];
1.121 markus 755: if (c == NULL)
756: continue;
757: switch (c->type) {
758: case SSH_CHANNEL_X11_LISTENER:
759: case SSH_CHANNEL_PORT_LISTENER:
760: case SSH_CHANNEL_RPORT_LISTENER:
761: case SSH_CHANNEL_CLOSED:
762: case SSH_CHANNEL_AUTH_SOCKET:
763: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 764: case SSH_CHANNEL_ABANDONED:
1.302 djm 765: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 766: case SSH_CHANNEL_UNIX_LISTENER:
767: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 768: continue;
769: case SSH_CHANNEL_LARVAL:
770: case SSH_CHANNEL_OPENING:
771: case SSH_CHANNEL_CONNECTING:
772: case SSH_CHANNEL_DYNAMIC:
1.372 markus 773: case SSH_CHANNEL_RDYNAMIC_OPEN:
774: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 775: case SSH_CHANNEL_OPEN:
776: case SSH_CHANNEL_X11_OPEN:
1.354 markus 777: case SSH_CHANNEL_MUX_PROXY:
778: case SSH_CHANNEL_MUX_CLIENT:
1.367 djm 779: if ((r = sshbuf_putf(buf, " #%d %.300s "
1.368 djm 780: "(t%d %s%u i%u/%zu o%u/%zu fd %d/%d cc %d)\r\n",
1.121 markus 781: c->self, c->remote_name,
1.368 djm 782: c->type,
783: c->have_remote_id ? "r" : "nr", c->remote_id,
1.367 djm 784: c->istate, sshbuf_len(c->input),
785: c->ostate, sshbuf_len(c->output),
786: c->rfd, c->wfd, c->ctl_chan)) != 0)
787: fatal("%s: sshbuf_putf: %s",
788: __func__, ssh_err(r));
1.121 markus 789: continue;
790: default:
1.367 djm 791: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 792: /* NOTREACHED */
793: }
794: }
1.367 djm 795: if ((ret = sshbuf_dup_string(buf)) == NULL)
796: fatal("%s: sshbuf_dup_string", __func__);
797: sshbuf_free(buf);
798: return ret;
799: }
800:
801: static void
802: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
803: {
804: int r;
805:
806: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
807: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
808: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
809: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
810: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
811: fatal("%s: channel %i: open: %s", where, c->self, ssh_err(r));
812: }
1.121 markus 813: }
814:
815: void
1.367 djm 816: channel_send_open(struct ssh *ssh, int id)
1.121 markus 817: {
1.367 djm 818: Channel *c = channel_lookup(ssh, id);
819: int r;
1.180 deraadt 820:
1.121 markus 821: if (c == NULL) {
1.188 itojun 822: logit("channel_send_open: %d: bad id", id);
1.121 markus 823: return;
824: }
1.184 markus 825: debug2("channel %d: send open", id);
1.367 djm 826: open_preamble(ssh, __func__, c, c->ctype);
827: if ((r = sshpkt_send(ssh)) != 0)
828: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.121 markus 829: }
830:
831: void
1.367 djm 832: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 833: {
1.367 djm 834: Channel *c = channel_lookup(ssh, id);
835: int r;
1.180 deraadt 836:
1.121 markus 837: if (c == NULL) {
1.367 djm 838: logit("%s: %d: unknown channel id", __func__, id);
1.121 markus 839: return;
840: }
1.368 djm 841: if (!c->have_remote_id)
842: fatal(":%s: channel %d: no remote id", __func__, c->self);
843:
1.204 djm 844: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 845: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
846: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
847: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
848: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
849: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
850: }
1.121 markus 851: }
1.241 deraadt 852:
1.121 markus 853: void
1.367 djm 854: channel_register_status_confirm(struct ssh *ssh, int id,
855: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 856: {
857: struct channel_confirm *cc;
858: Channel *c;
859:
1.367 djm 860: if ((c = channel_lookup(ssh, id)) == NULL)
861: fatal("%s: %d: bad id", __func__, id);
1.275 djm 862:
1.327 djm 863: cc = xcalloc(1, sizeof(*cc));
1.275 djm 864: cc->cb = cb;
865: cc->abandon_cb = abandon_cb;
866: cc->ctx = ctx;
867: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
868: }
869:
870: void
1.367 djm 871: channel_register_open_confirm(struct ssh *ssh, int id,
872: channel_open_fn *fn, void *ctx)
1.121 markus 873: {
1.367 djm 874: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 875:
1.121 markus 876: if (c == NULL) {
1.367 djm 877: logit("%s: %d: bad id", __func__, id);
1.121 markus 878: return;
879: }
1.275 djm 880: c->open_confirm = fn;
881: c->open_confirm_ctx = ctx;
1.121 markus 882: }
1.241 deraadt 883:
1.121 markus 884: void
1.367 djm 885: channel_register_cleanup(struct ssh *ssh, int id,
886: channel_callback_fn *fn, int do_close)
1.121 markus 887: {
1.367 djm 888: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 889:
1.121 markus 890: if (c == NULL) {
1.367 djm 891: logit("%s: %d: bad id", __func__, id);
1.121 markus 892: return;
893: }
1.131 markus 894: c->detach_user = fn;
1.225 djm 895: c->detach_close = do_close;
1.121 markus 896: }
1.241 deraadt 897:
1.121 markus 898: void
1.367 djm 899: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 900: {
1.367 djm 901: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 902:
1.121 markus 903: if (c == NULL) {
1.367 djm 904: logit("%s: %d: bad id", __func__, id);
1.121 markus 905: return;
1.52 markus 906: }
1.131 markus 907: c->detach_user = NULL;
1.225 djm 908: c->detach_close = 0;
1.121 markus 909: }
1.241 deraadt 910:
1.121 markus 911: void
1.367 djm 912: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 913: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 914: {
1.367 djm 915: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 916:
1.121 markus 917: if (c == NULL) {
1.367 djm 918: logit("%s: %d: bad id", __func__, id);
1.121 markus 919: return;
1.52 markus 920: }
1.231 reyk 921: c->input_filter = ifn;
922: c->output_filter = ofn;
1.279 djm 923: c->filter_ctx = ctx;
1.280 djm 924: c->filter_cleanup = cfn;
1.52 markus 925: }
926:
1.49 markus 927: void
1.367 djm 928: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 929: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 930: {
1.367 djm 931: Channel *c = channel_lookup(ssh, id);
932: int r;
1.180 deraadt 933:
1.121 markus 934: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
935: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 936: if (!c->have_remote_id)
937: fatal(":%s: channel %d: no remote id", __func__, c->self);
938:
1.367 djm 939: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 940: c->type = SSH_CHANNEL_OPEN;
1.168 markus 941: c->local_window = c->local_window_max = window_max;
1.367 djm 942:
943: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
944: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
945: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
946: (r = sshpkt_send(ssh)) != 0)
947: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.1 deraadt 948: }
949:
1.127 itojun 950: static void
1.367 djm 951: channel_pre_listener(struct ssh *ssh, Channel *c,
952: fd_set *readset, fd_set *writeset)
1.41 markus 953: {
954: FD_SET(c->sock, readset);
955: }
956:
1.127 itojun 957: static void
1.367 djm 958: channel_pre_connecting(struct ssh *ssh, Channel *c,
959: fd_set *readset, fd_set *writeset)
1.75 markus 960: {
961: debug3("channel %d: waiting for connection", c->self);
962: FD_SET(c->sock, writeset);
963: }
964:
1.127 itojun 965: static void
1.367 djm 966: channel_pre_open(struct ssh *ssh, Channel *c,
967: fd_set *readset, fd_set *writeset)
1.41 markus 968: {
1.44 markus 969: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 970: c->remote_window > 0 &&
1.367 djm 971: sshbuf_len(c->input) < c->remote_window &&
972: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.44 markus 973: FD_SET(c->rfd, readset);
974: if (c->ostate == CHAN_OUTPUT_OPEN ||
975: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 976: if (sshbuf_len(c->output) > 0) {
1.44 markus 977: FD_SET(c->wfd, writeset);
978: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 979: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 980: debug2("channel %d: "
981: "obuf_empty delayed efd %d/(%zu)", c->self,
982: c->efd, sshbuf_len(c->extended));
1.172 markus 983: else
1.367 djm 984: chan_obuf_empty(ssh, c);
1.44 markus 985: }
986: }
987: /** XXX check close conditions, too */
1.358 djm 988: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
989: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 990: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 991: sshbuf_len(c->extended) > 0)
1.44 markus 992: FD_SET(c->efd, writeset);
1.306 djm 993: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
994: (c->extended_usage == CHAN_EXTENDED_READ ||
995: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 996: sshbuf_len(c->extended) < c->remote_window)
1.44 markus 997: FD_SET(c->efd, readset);
998: }
1.204 djm 999: /* XXX: What about efd? races? */
1.44 markus 1000: }
1001:
1.41 markus 1002: /*
1003: * This is a special state for X11 authentication spoofing. An opened X11
1004: * connection (when authentication spoofing is being done) remains in this
1005: * state until the first packet has been completely read. The authentication
1006: * data in that packet is then substituted by the real data if it matches the
1007: * fake data, and the channel is put into normal mode.
1.51 markus 1008: * XXX All this happens at the client side.
1.121 markus 1009: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1010: */
1.127 itojun 1011: static int
1.367 djm 1012: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1013: {
1.367 djm 1014: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1015: u_char *ucp;
1016: u_int proto_len, data_len;
1.25 markus 1017:
1.347 djm 1018: /* Is this being called after the refusal deadline? */
1.367 djm 1019: if (sc->x11_refuse_time != 0 &&
1020: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1021: verbose("Rejected X11 connection after ForwardX11Timeout "
1022: "expired");
1023: return -1;
1024: }
1025:
1.41 markus 1026: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1027: if (sshbuf_len(b) < 12)
1.41 markus 1028: return 0;
1029:
1030: /* Parse the lengths of variable-length fields. */
1.367 djm 1031: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1032: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1033: proto_len = 256 * ucp[6] + ucp[7];
1034: data_len = 256 * ucp[8] + ucp[9];
1035: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1036: proto_len = ucp[6] + 256 * ucp[7];
1037: data_len = ucp[8] + 256 * ucp[9];
1038: } else {
1.194 markus 1039: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1040: ucp[0]);
1.41 markus 1041: return -1;
1042: }
1043:
1044: /* Check if the whole packet is in buffer. */
1.367 djm 1045: if (sshbuf_len(b) <
1.41 markus 1046: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1047: return 0;
1048:
1049: /* Check if authentication protocol matches. */
1.367 djm 1050: if (proto_len != strlen(sc->x11_saved_proto) ||
1051: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1052: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1053: return -1;
1054: }
1055: /* Check if authentication data matches our fake data. */
1.367 djm 1056: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1057: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1058: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1059: debug2("X11 auth data does not match fake data.");
1.41 markus 1060: return -1;
1061: }
1062: /* Check fake data length */
1.367 djm 1063: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1064: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1065: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1066: return -1;
1067: }
1068: /*
1069: * Received authentication protocol and data match
1070: * our fake data. Substitute the fake data with real
1071: * data.
1072: */
1073: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1074: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1075: return 1;
1076: }
1077:
1.127 itojun 1078: static void
1.367 djm 1079: channel_pre_x11_open(struct ssh *ssh, Channel *c,
1080: fd_set *readset, fd_set *writeset)
1.41 markus 1081: {
1.367 djm 1082: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1083:
1084: /* c->force_drain = 1; */
1085:
1.41 markus 1086: if (ret == 1) {
1087: c->type = SSH_CHANNEL_OPEN;
1.367 djm 1088: channel_pre_open(ssh, c, readset, writeset);
1.41 markus 1089: } else if (ret == -1) {
1.188 itojun 1090: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1091: debug2("X11 rejected %d i%d/o%d",
1092: c->self, c->istate, c->ostate);
1093: chan_read_failed(ssh, c);
1094: sshbuf_reset(c->input);
1095: chan_ibuf_empty(ssh, c);
1096: sshbuf_reset(c->output);
1097: chan_write_failed(ssh, c);
1.194 markus 1098: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1099: }
1100: }
1.25 markus 1101:
1.302 djm 1102: static void
1.367 djm 1103: channel_pre_mux_client(struct ssh *ssh,
1104: Channel *c, fd_set *readset, fd_set *writeset)
1.302 djm 1105: {
1.304 djm 1106: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1107: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.302 djm 1108: FD_SET(c->rfd, readset);
1109: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1110: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1111: sshbuf_reset(c->input);
1112: chan_ibuf_empty(ssh, c);
1.302 djm 1113: /* Start output drain. XXX just kill chan? */
1.367 djm 1114: chan_rcvd_oclose(ssh, c);
1.302 djm 1115: }
1116: if (c->ostate == CHAN_OUTPUT_OPEN ||
1117: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1118: if (sshbuf_len(c->output) > 0)
1.302 djm 1119: FD_SET(c->wfd, writeset);
1120: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1121: chan_obuf_empty(ssh, c);
1.302 djm 1122: }
1123: }
1124:
1.104 markus 1125: /* try to decode a socks4 header */
1.127 itojun 1126: static int
1.372 markus 1127: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1128: {
1.367 djm 1129: const u_char *p;
1130: char *host;
1.292 djm 1131: u_int len, have, i, found, need;
1.148 deraadt 1132: char username[256];
1.103 markus 1133: struct {
1134: u_int8_t version;
1135: u_int8_t command;
1136: u_int16_t dest_port;
1.104 markus 1137: struct in_addr dest_addr;
1.103 markus 1138: } s4_req, s4_rsp;
1.367 djm 1139: int r;
1.103 markus 1140:
1.104 markus 1141: debug2("channel %d: decode socks4", c->self);
1.109 markus 1142:
1.372 markus 1143: have = sshbuf_len(input);
1.109 markus 1144: len = sizeof(s4_req);
1145: if (have < len)
1146: return 0;
1.372 markus 1147: p = sshbuf_ptr(input);
1.292 djm 1148:
1149: need = 1;
1150: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1151: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1152: debug2("channel %d: socks4a request", c->self);
1153: /* ... and needs an extra string (the hostname) */
1154: need = 2;
1155: }
1156: /* Check for terminating NUL on the string(s) */
1.109 markus 1157: for (found = 0, i = len; i < have; i++) {
1158: if (p[i] == '\0') {
1.292 djm 1159: found++;
1160: if (found == need)
1161: break;
1.109 markus 1162: }
1163: if (i > 1024) {
1164: /* the peer is probably sending garbage */
1165: debug("channel %d: decode socks4: too long",
1166: c->self);
1167: return -1;
1168: }
1169: }
1.292 djm 1170: if (found < need)
1.109 markus 1171: return 0;
1.372 markus 1172: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1173: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1174: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1175: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.367 djm 1176: debug("channels %d: decode socks4: %s", c->self, ssh_err(r));
1177: return -1;
1178: }
1.372 markus 1179: have = sshbuf_len(input);
1180: p = sshbuf_ptr(input);
1.364 djm 1181: if (memchr(p, '\0', have) == NULL) {
1182: error("channel %d: decode socks4: user not nul terminated",
1.331 djm 1183: c->self);
1.364 djm 1184: return -1;
1185: }
1.103 markus 1186: len = strlen(p);
1.106 markus 1187: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1188: len++; /* trailing '\0' */
1.103 markus 1189: strlcpy(username, p, sizeof(username));
1.372 markus 1190: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1191: fatal("%s: channel %d: consume: %s", __func__,
1192: c->self, ssh_err(r));
1193: }
1.321 djm 1194: free(c->path);
1195: c->path = NULL;
1.292 djm 1196: if (need == 1) { /* SOCKS4: one string */
1197: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1198: c->path = xstrdup(host);
1.292 djm 1199: } else { /* SOCKS4A: two strings */
1.372 markus 1200: have = sshbuf_len(input);
1201: p = sshbuf_ptr(input);
1.364 djm 1202: if (memchr(p, '\0', have) == NULL) {
1203: error("channel %d: decode socks4a: host not nul "
1204: "terminated", c->self);
1205: return -1;
1206: }
1.292 djm 1207: len = strlen(p);
1208: debug2("channel %d: decode socks4a: host %s/%d",
1209: c->self, p, len);
1210: len++; /* trailing '\0' */
1.293 djm 1211: if (len > NI_MAXHOST) {
1.292 djm 1212: error("channel %d: hostname \"%.100s\" too long",
1213: c->self, p);
1214: return -1;
1215: }
1.293 djm 1216: c->path = xstrdup(p);
1.372 markus 1217: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1218: fatal("%s: channel %d: consume: %s", __func__,
1219: c->self, ssh_err(r));
1220: }
1.292 djm 1221: }
1.103 markus 1222: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1223:
1.194 markus 1224: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1225: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1226:
1.104 markus 1227: if (s4_req.command != 1) {
1.292 djm 1228: debug("channel %d: cannot handle: %s cn %d",
1229: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1230: return -1;
1.103 markus 1231: }
1.104 markus 1232: s4_rsp.version = 0; /* vn: 0 for reply */
1233: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1234: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1235: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.372 markus 1236: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0) {
1.367 djm 1237: fatal("%s: channel %d: append reply: %s", __func__,
1238: c->self, ssh_err(r));
1239: }
1.104 markus 1240: return 1;
1241: }
1242:
1.193 markus 1243: /* try to decode a socks5 header */
1244: #define SSH_SOCKS5_AUTHDONE 0x1000
1245: #define SSH_SOCKS5_NOAUTH 0x00
1246: #define SSH_SOCKS5_IPV4 0x01
1247: #define SSH_SOCKS5_DOMAIN 0x03
1248: #define SSH_SOCKS5_IPV6 0x04
1249: #define SSH_SOCKS5_CONNECT 0x01
1250: #define SSH_SOCKS5_SUCCESS 0x00
1251:
1252: static int
1.372 markus 1253: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1254: {
1.367 djm 1255: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1256: struct {
1257: u_int8_t version;
1258: u_int8_t command;
1259: u_int8_t reserved;
1260: u_int8_t atyp;
1261: } s5_req, s5_rsp;
1262: u_int16_t dest_port;
1.324 djm 1263: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1264: const u_char *p;
1.252 djm 1265: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1266: int r;
1.193 markus 1267:
1268: debug2("channel %d: decode socks5", c->self);
1.372 markus 1269: p = sshbuf_ptr(input);
1.193 markus 1270: if (p[0] != 0x05)
1271: return -1;
1.372 markus 1272: have = sshbuf_len(input);
1.193 markus 1273: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1274: /* format: ver | nmethods | methods */
1.198 djm 1275: if (have < 2)
1.193 markus 1276: return 0;
1277: nmethods = p[1];
1278: if (have < nmethods + 2)
1279: return 0;
1280: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1281: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1282: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1283: found = 1;
1284: break;
1285: }
1286: }
1287: if (!found) {
1288: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1289: c->self);
1290: return -1;
1291: }
1.372 markus 1292: if ((r = sshbuf_consume(input, nmethods + 2)) != 0) {
1.367 djm 1293: fatal("%s: channel %d: consume: %s", __func__,
1294: c->self, ssh_err(r));
1295: }
1296: /* version, method */
1.372 markus 1297: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1298: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0) {
1.367 djm 1299: fatal("%s: channel %d: append reply: %s", __func__,
1300: c->self, ssh_err(r));
1301: }
1.193 markus 1302: c->flags |= SSH_SOCKS5_AUTHDONE;
1303: debug2("channel %d: socks5 auth done", c->self);
1304: return 0; /* need more */
1305: }
1306: debug2("channel %d: socks5 post auth", c->self);
1307: if (have < sizeof(s5_req)+1)
1308: return 0; /* need more */
1.247 deraadt 1309: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1310: if (s5_req.version != 0x05 ||
1311: s5_req.command != SSH_SOCKS5_CONNECT ||
1312: s5_req.reserved != 0x00) {
1.194 markus 1313: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1314: return -1;
1315: }
1.213 deraadt 1316: switch (s5_req.atyp){
1.193 markus 1317: case SSH_SOCKS5_IPV4:
1318: addrlen = 4;
1319: af = AF_INET;
1320: break;
1321: case SSH_SOCKS5_DOMAIN:
1322: addrlen = p[sizeof(s5_req)];
1323: af = -1;
1324: break;
1325: case SSH_SOCKS5_IPV6:
1326: addrlen = 16;
1327: af = AF_INET6;
1328: break;
1329: default:
1.194 markus 1330: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1331: return -1;
1332: }
1.252 djm 1333: need = sizeof(s5_req) + addrlen + 2;
1334: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1335: need++;
1336: if (have < need)
1.193 markus 1337: return 0;
1.372 markus 1338: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0) {
1.367 djm 1339: fatal("%s: channel %d: consume: %s", __func__,
1340: c->self, ssh_err(r));
1341: }
1342: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1343: /* host string length */
1.372 markus 1344: if ((r = sshbuf_consume(input, 1)) != 0) {
1.367 djm 1345: fatal("%s: channel %d: consume: %s", __func__,
1346: c->self, ssh_err(r));
1347: }
1348: }
1.372 markus 1349: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1350: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.367 djm 1351: debug("channel %d: parse addr/port: %s", c->self, ssh_err(r));
1352: return -1;
1353: }
1.193 markus 1354: dest_addr[addrlen] = '\0';
1.321 djm 1355: free(c->path);
1356: c->path = NULL;
1.293 djm 1357: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1358: if (addrlen >= NI_MAXHOST) {
1.293 djm 1359: error("channel %d: dynamic request: socks5 hostname "
1360: "\"%.100s\" too long", c->self, dest_addr);
1361: return -1;
1362: }
1363: c->path = xstrdup(dest_addr);
1364: } else {
1365: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1366: return -1;
1367: c->path = xstrdup(ntop);
1368: }
1.193 markus 1369: c->host_port = ntohs(dest_port);
1.198 djm 1370:
1.194 markus 1371: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1372: c->self, c->path, c->host_port, s5_req.command);
1373:
1374: s5_rsp.version = 0x05;
1375: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1376: s5_rsp.reserved = 0; /* ignored */
1377: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1378: dest_port = 0; /* ignored */
1379:
1.372 markus 1380: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1381: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1382: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.367 djm 1383: fatal("%s: channel %d: append reply: %s", __func__,
1384: c->self, ssh_err(r));
1.193 markus 1385: return 1;
1.301 dtucker 1386: }
1387:
1388: Channel *
1.367 djm 1389: channel_connect_stdio_fwd(struct ssh *ssh,
1390: const char *host_to_connect, u_short port_to_connect, int in, int out)
1.301 dtucker 1391: {
1392: Channel *c;
1393:
1.367 djm 1394: debug("%s %s:%d", __func__, host_to_connect, port_to_connect);
1.301 dtucker 1395:
1.367 djm 1396: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1397: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1398: 0, "stdio-forward", /*nonblock*/0);
1399:
1400: c->path = xstrdup(host_to_connect);
1401: c->host_port = port_to_connect;
1402: c->listening_port = 0;
1403: c->force_drain = 1;
1404:
1.367 djm 1405: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1406: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1407:
1408: return c;
1.193 markus 1409: }
1410:
1.104 markus 1411: /* dynamic port forwarding */
1.127 itojun 1412: static void
1.367 djm 1413: channel_pre_dynamic(struct ssh *ssh, Channel *c,
1414: fd_set *readset, fd_set *writeset)
1.104 markus 1415: {
1.367 djm 1416: const u_char *p;
1.217 djm 1417: u_int have;
1418: int ret;
1.103 markus 1419:
1.367 djm 1420: have = sshbuf_len(c->input);
1.104 markus 1421: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1422: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1423: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1424: if (have < 3) {
1.104 markus 1425: /* need more */
1426: FD_SET(c->sock, readset);
1427: return;
1428: }
1429: /* try to guess the protocol */
1.367 djm 1430: p = sshbuf_ptr(c->input);
1431: /* XXX sshbuf_peek_u8? */
1.104 markus 1432: switch (p[0]) {
1433: case 0x04:
1.372 markus 1434: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1435: break;
1436: case 0x05:
1.372 markus 1437: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1438: break;
1439: default:
1440: ret = -1;
1441: break;
1442: }
1443: if (ret < 0) {
1.367 djm 1444: chan_mark_dead(ssh, c);
1.104 markus 1445: } else if (ret == 0) {
1446: debug2("channel %d: pre_dynamic: need more", c->self);
1447: /* need more */
1448: FD_SET(c->sock, readset);
1.372 markus 1449: if (sshbuf_len(c->output))
1450: FD_SET(c->sock, writeset);
1.104 markus 1451: } else {
1452: /* switch to the next state */
1453: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1454: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1455: }
1.103 markus 1456: }
1457:
1.372 markus 1458: /* simulate read-error */
1459: static void
1460: rdynamic_close(struct ssh *ssh, Channel *c)
1461: {
1462: c->type = SSH_CHANNEL_OPEN;
1463: chan_read_failed(ssh, c);
1464: sshbuf_reset(c->input);
1465: chan_ibuf_empty(ssh, c);
1466: sshbuf_reset(c->output);
1467: chan_write_failed(ssh, c);
1468: }
1469:
1470: /* reverse dynamic port forwarding */
1471: static void
1472: channel_before_prepare_select_rdynamic(struct ssh *ssh, Channel *c)
1473: {
1474: const u_char *p;
1475: u_int have, len;
1476: int r, ret;
1477:
1478: have = sshbuf_len(c->output);
1479: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1480: /* sshbuf_dump(c->output, stderr); */
1481: /* EOF received */
1482: if (c->flags & CHAN_EOF_RCVD) {
1483: if ((r = sshbuf_consume(c->output, have)) != 0) {
1484: fatal("%s: channel %d: consume: %s",
1485: __func__, c->self, ssh_err(r));
1486: }
1487: rdynamic_close(ssh, c);
1488: return;
1489: }
1490: /* check if the fixed size part of the packet is in buffer. */
1491: if (have < 3)
1492: return;
1493: /* try to guess the protocol */
1494: p = sshbuf_ptr(c->output);
1495: switch (p[0]) {
1496: case 0x04:
1497: /* switch input/output for reverse forwarding */
1498: ret = channel_decode_socks4(c, c->output, c->input);
1499: break;
1500: case 0x05:
1501: ret = channel_decode_socks5(c, c->output, c->input);
1502: break;
1503: default:
1504: ret = -1;
1505: break;
1506: }
1507: if (ret < 0) {
1508: rdynamic_close(ssh, c);
1509: } else if (ret == 0) {
1510: debug2("channel %d: pre_rdynamic: need more", c->self);
1511: /* send socks request to peer */
1512: len = sshbuf_len(c->input);
1513: if (len > 0 && len < c->remote_window) {
1514: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1515: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1516: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1517: (r = sshpkt_send(ssh)) != 0) {
1518: fatal("%s: channel %i: rdynamic: %s", __func__,
1519: c->self, ssh_err(r));
1520: }
1521: if ((r = sshbuf_consume(c->input, len)) != 0) {
1522: fatal("%s: channel %d: consume: %s",
1523: __func__, c->self, ssh_err(r));
1524: }
1525: c->remote_window -= len;
1526: }
1527: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1528: /* the connect failed */
1529: rdynamic_close(ssh, c);
1530: }
1531: }
1532:
1.41 markus 1533: /* This is our fake X11 server socket. */
1.127 itojun 1534: static void
1.367 djm 1535: channel_post_x11_listener(struct ssh *ssh, Channel *c,
1536: fd_set *readset, fd_set *writeset)
1.41 markus 1537: {
1.113 markus 1538: Channel *nc;
1.285 djm 1539: struct sockaddr_storage addr;
1.367 djm 1540: int r, newsock, oerrno, remote_port;
1.41 markus 1541: socklen_t addrlen;
1.85 markus 1542: char buf[16384], *remote_ipaddr;
1.25 markus 1543:
1.367 djm 1544: if (!FD_ISSET(c->sock, readset))
1545: return;
1546:
1547: debug("X11 connection requested.");
1548: addrlen = sizeof(addr);
1549: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1550: if (c->single_connection) {
1551: oerrno = errno;
1552: debug2("single_connection: closing X11 listener.");
1553: channel_close_fd(ssh, &c->sock);
1554: chan_mark_dead(ssh, c);
1555: errno = oerrno;
1556: }
1557: if (newsock < 0) {
1558: if (errno != EINTR && errno != EWOULDBLOCK &&
1559: errno != ECONNABORTED)
1560: error("accept: %.100s", strerror(errno));
1561: if (errno == EMFILE || errno == ENFILE)
1562: c->notbefore = monotime() + 1;
1563: return;
1564: }
1565: set_nodelay(newsock);
1566: remote_ipaddr = get_peer_ipaddr(newsock);
1567: remote_port = get_peer_port(newsock);
1568: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1569: remote_ipaddr, remote_port);
1570:
1571: nc = channel_new(ssh, "accepted x11 socket",
1572: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1573: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1574: open_preamble(ssh, __func__, nc, "x11");
1.378 ! djm 1575: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
! 1576: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.367 djm 1577: fatal("%s: channel %i: reply %s", __func__,
1578: c->self, ssh_err(r));
1.41 markus 1579: }
1.367 djm 1580: if ((r = sshpkt_send(ssh)) != 0)
1581: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1582: free(remote_ipaddr);
1.41 markus 1583: }
1.25 markus 1584:
1.127 itojun 1585: static void
1.367 djm 1586: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1587: {
1.328 djm 1588: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1589: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1590: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1591: int remote_port = get_peer_port(c->sock);
1.367 djm 1592: int r;
1.303 djm 1593:
1594: if (remote_port == -1) {
1595: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1596: free(remote_ipaddr);
1.303 djm 1597: remote_ipaddr = xstrdup("127.0.0.1");
1598: remote_port = 65535;
1599: }
1.103 markus 1600:
1.367 djm 1601: free(c->remote_name);
1602: xasprintf(&c->remote_name,
1.103 markus 1603: "%s: listening port %d for %.100s port %d, "
1.328 djm 1604: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1605: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1606: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1607:
1.367 djm 1608: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1609: if (strcmp(rtype, "direct-tcpip") == 0) {
1610: /* target host, port */
1.367 djm 1611: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1612: (r = sshpkt_put_u32(ssh, c->host_port)) != 0) {
1613: fatal("%s: channel %i: reply %s", __func__,
1614: c->self, ssh_err(r));
1615: }
1.358 djm 1616: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1617: /* target path */
1.367 djm 1618: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1619: fatal("%s: channel %i: reply %s", __func__,
1620: c->self, ssh_err(r));
1621: }
1.358 djm 1622: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1623: /* listen path */
1.367 djm 1624: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1625: fatal("%s: channel %i: reply %s", __func__,
1626: c->self, ssh_err(r));
1627: }
1.103 markus 1628: } else {
1.358 djm 1629: /* listen address, port */
1.367 djm 1630: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1631: (r = sshpkt_put_u32(ssh, local_port)) != 0) {
1632: fatal("%s: channel %i: reply %s", __func__,
1633: c->self, ssh_err(r));
1634: }
1.358 djm 1635: }
1636: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1637: /* reserved for future owner/mode info */
1.367 djm 1638: if ((r = sshpkt_put_cstring(ssh, "")) != 0) {
1639: fatal("%s: channel %i: reply %s", __func__,
1640: c->self, ssh_err(r));
1641: }
1.358 djm 1642: } else {
1643: /* originator host and port */
1.367 djm 1644: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1645: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0) {
1646: fatal("%s: channel %i: reply %s", __func__,
1647: c->self, ssh_err(r));
1648: }
1.103 markus 1649: }
1.367 djm 1650: if ((r = sshpkt_send(ssh)) != 0)
1651: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1.321 djm 1652: free(remote_ipaddr);
1.328 djm 1653: free(local_ipaddr);
1.103 markus 1654: }
1655:
1.347 djm 1656: void
1.367 djm 1657: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1658: {
1.367 djm 1659: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1660: }
1661:
1.41 markus 1662: /*
1663: * This socket is listening for connections to a forwarded TCP/IP port.
1664: */
1.127 itojun 1665: static void
1.367 djm 1666: channel_post_port_listener(struct ssh *ssh, Channel *c,
1667: fd_set *readset, fd_set *writeset)
1.41 markus 1668: {
1.103 markus 1669: Channel *nc;
1.285 djm 1670: struct sockaddr_storage addr;
1.113 markus 1671: int newsock, nextstate;
1.41 markus 1672: socklen_t addrlen;
1.103 markus 1673: char *rtype;
1.73 markus 1674:
1.367 djm 1675: if (!FD_ISSET(c->sock, readset))
1676: return;
1677:
1678: debug("Connection to port %d forwarding to %.100s port %d requested.",
1679: c->listening_port, c->path, c->host_port);
1.103 markus 1680:
1.367 djm 1681: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1682: nextstate = SSH_CHANNEL_OPENING;
1683: rtype = "forwarded-tcpip";
1684: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1685: nextstate = SSH_CHANNEL_OPENING;
1686: rtype = "forwarded-streamlocal@openssh.com";
1687: } else if (c->host_port == PORT_STREAMLOCAL) {
1688: nextstate = SSH_CHANNEL_OPENING;
1689: rtype = "direct-streamlocal@openssh.com";
1690: } else if (c->host_port == 0) {
1691: nextstate = SSH_CHANNEL_DYNAMIC;
1692: rtype = "dynamic-tcpip";
1693: } else {
1694: nextstate = SSH_CHANNEL_OPENING;
1695: rtype = "direct-tcpip";
1696: }
1.103 markus 1697:
1.367 djm 1698: addrlen = sizeof(addr);
1699: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1700: if (newsock < 0) {
1701: if (errno != EINTR && errno != EWOULDBLOCK &&
1702: errno != ECONNABORTED)
1703: error("accept: %.100s", strerror(errno));
1704: if (errno == EMFILE || errno == ENFILE)
1705: c->notbefore = monotime() + 1;
1706: return;
1.41 markus 1707: }
1.367 djm 1708: if (c->host_port != PORT_STREAMLOCAL)
1709: set_nodelay(newsock);
1710: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1711: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1712: nc->listening_port = c->listening_port;
1713: nc->host_port = c->host_port;
1714: if (c->path != NULL)
1715: nc->path = xstrdup(c->path);
1716:
1717: if (nextstate != SSH_CHANNEL_DYNAMIC)
1718: port_open_helper(ssh, nc, rtype);
1.41 markus 1719: }
1.25 markus 1720:
1.41 markus 1721: /*
1722: * This is the authentication agent socket listening for connections from
1723: * clients.
1724: */
1.127 itojun 1725: static void
1.367 djm 1726: channel_post_auth_listener(struct ssh *ssh, Channel *c,
1727: fd_set *readset, fd_set *writeset)
1.41 markus 1728: {
1.113 markus 1729: Channel *nc;
1.367 djm 1730: int r, newsock;
1.285 djm 1731: struct sockaddr_storage addr;
1.41 markus 1732: socklen_t addrlen;
1.25 markus 1733:
1.367 djm 1734: if (!FD_ISSET(c->sock, readset))
1735: return;
1736:
1737: addrlen = sizeof(addr);
1738: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1739: if (newsock < 0) {
1740: error("accept from auth socket: %.100s", strerror(errno));
1741: if (errno == EMFILE || errno == ENFILE)
1742: c->notbefore = monotime() + 1;
1743: return;
1.41 markus 1744: }
1.367 djm 1745: nc = channel_new(ssh, "accepted auth socket",
1746: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1747: c->local_window_max, c->local_maxpacket,
1748: 0, "accepted auth socket", 1);
1749: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1750: if ((r = sshpkt_send(ssh)) != 0)
1751: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.41 markus 1752: }
1.25 markus 1753:
1.127 itojun 1754: static void
1.367 djm 1755: channel_post_connecting(struct ssh *ssh, Channel *c,
1756: fd_set *readset, fd_set *writeset)
1.75 markus 1757: {
1.372 markus 1758: int err = 0, sock, isopen, r;
1.129 stevesk 1759: socklen_t sz = sizeof(err);
1.114 markus 1760:
1.367 djm 1761: if (!FD_ISSET(c->sock, writeset))
1762: return;
1.368 djm 1763: if (!c->have_remote_id)
1764: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.372 markus 1765: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1766: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.367 djm 1767: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1768: err = errno;
1769: error("getsockopt SO_ERROR failed");
1770: }
1771: if (err == 0) {
1772: debug("channel %d: connected to %s port %d",
1773: c->self, c->connect_ctx.host, c->connect_ctx.port);
1774: channel_connect_ctx_free(&c->connect_ctx);
1775: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1776: if (isopen) {
1777: /* no message necessary */
1778: } else {
1779: if ((r = sshpkt_start(ssh,
1780: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1781: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1782: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1783: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1784: (r = sshpkt_put_u32(ssh, c->local_maxpacket))
1785: != 0)
1786: fatal("%s: channel %i: confirm: %s", __func__,
1787: c->self, ssh_err(r));
1788: if ((r = sshpkt_send(ssh)) != 0)
1789: fatal("%s: channel %i: %s", __func__, c->self,
1790: ssh_err(r));
1.367 djm 1791: }
1792: } else {
1793: debug("channel %d: connection failed: %s",
1794: c->self, strerror(err));
1795: /* Try next address, if any */
1796: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1797: close(c->sock);
1798: c->sock = c->rfd = c->wfd = sock;
1799: channel_find_maxfd(ssh->chanctxt);
1800: return;
1801: }
1802: /* Exhausted all addresses */
1803: error("connect_to %.100s port %d: failed.",
1804: c->connect_ctx.host, c->connect_ctx.port);
1805: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1806: if (isopen) {
1807: rdynamic_close(ssh, c);
1808: } else {
1809: if ((r = sshpkt_start(ssh,
1810: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1811: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 ! djm 1812: (r = sshpkt_put_u32(ssh,
! 1813: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
! 1814: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
! 1815: (r = sshpkt_put_cstring(ssh, "")) != 0) {
1.372 markus 1816: fatal("%s: channel %i: failure: %s", __func__,
1817: c->self, ssh_err(r));
1.378 ! djm 1818: }
1.372 markus 1819: if ((r = sshpkt_send(ssh)) != 0)
1820: fatal("%s: channel %i: %s", __func__, c->self,
1821: ssh_err(r));
1822: chan_mark_dead(ssh, c);
1.75 markus 1823: }
1824: }
1825: }
1826:
1.127 itojun 1827: static int
1.367 djm 1828: channel_handle_rfd(struct ssh *ssh, Channel *c,
1829: fd_set *readset, fd_set *writeset)
1.41 markus 1830: {
1.214 markus 1831: char buf[CHAN_RBUF];
1.367 djm 1832: ssize_t len;
1833: int r;
1.25 markus 1834:
1.367 djm 1835: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
1836: return 1;
1837:
1838: len = read(c->rfd, buf, sizeof(buf));
1839: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1840: return 1;
1841: if (len <= 0) {
1842: debug2("channel %d: read<=0 rfd %d len %zd",
1843: c->self, c->rfd, len);
1844: if (c->type != SSH_CHANNEL_OPEN) {
1845: debug2("channel %d: not open", c->self);
1846: chan_mark_dead(ssh, c);
1.41 markus 1847: return -1;
1.65 markus 1848: } else {
1.367 djm 1849: chan_read_failed(ssh, c);
1.65 markus 1850: }
1.367 djm 1851: return -1;
1852: }
1853: if (c->input_filter != NULL) {
1854: if (c->input_filter(ssh, c, buf, len) == -1) {
1855: debug2("channel %d: filter stops", c->self);
1856: chan_read_failed(ssh, c);
1857: }
1858: } else if (c->datagram) {
1859: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1860: fatal("%s: channel %d: put datagram: %s", __func__,
1861: c->self, ssh_err(r));
1862: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
1863: fatal("%s: channel %d: put data: %s", __func__,
1864: c->self, ssh_err(r));
1.41 markus 1865: }
1866: return 1;
1867: }
1.241 deraadt 1868:
1.127 itojun 1869: static int
1.367 djm 1870: channel_handle_wfd(struct ssh *ssh, Channel *c,
1871: fd_set *readset, fd_set *writeset)
1.41 markus 1872: {
1.95 markus 1873: struct termios tio;
1.367 djm 1874: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1875: size_t dlen, olen = 0;
1876: int r, len;
1877:
1878: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
1879: sshbuf_len(c->output) == 0)
1880: return 1;
1.25 markus 1881:
1.41 markus 1882: /* Send buffered output data to the socket. */
1.367 djm 1883: olen = sshbuf_len(c->output);
1884: if (c->output_filter != NULL) {
1885: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1886: debug2("channel %d: filter stops", c->self);
1887: if (c->type != SSH_CHANNEL_OPEN)
1888: chan_mark_dead(ssh, c);
1889: else
1890: chan_write_failed(ssh, c);
1891: return -1;
1.231 reyk 1892: }
1.367 djm 1893: } else if (c->datagram) {
1894: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1895: fatal("%s: channel %d: get datagram: %s", __func__,
1896: c->self, ssh_err(r));
1.369 djm 1897: buf = data;
1.367 djm 1898: } else {
1899: buf = data = sshbuf_mutable_ptr(c->output);
1900: dlen = sshbuf_len(c->output);
1901: }
1.231 reyk 1902:
1.367 djm 1903: if (c->datagram) {
1904: /* ignore truncated writes, datagrams might get lost */
1.374 djm 1905: len = write(c->wfd, buf, dlen);
1.367 djm 1906: free(data);
1.53 markus 1907: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1908: return 1;
1.367 djm 1909: if (len <= 0)
1910: goto write_fail;
1911: goto out;
1912: }
1913:
1914: len = write(c->wfd, buf, dlen);
1915: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1916: return 1;
1917: if (len <= 0) {
1918: write_fail:
1919: if (c->type != SSH_CHANNEL_OPEN) {
1920: debug2("channel %d: not open", c->self);
1921: chan_mark_dead(ssh, c);
1.41 markus 1922: return -1;
1.367 djm 1923: } else {
1924: chan_write_failed(ssh, c);
1.91 markus 1925: }
1.367 djm 1926: return -1;
1927: }
1928: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
1929: if (tcgetattr(c->wfd, &tio) == 0 &&
1930: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1931: /*
1932: * Simulate echo to reduce the impact of
1933: * traffic analysis. We need to match the
1934: * size of a SSH2_MSG_CHANNEL_DATA message
1935: * (4 byte channel id + buf)
1936: */
1937: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
1938: (r = sshpkt_send(ssh)) != 0)
1939: fatal("%s: channel %d: ignore: %s",
1940: __func__, c->self, ssh_err(r));
1.25 markus 1941: }
1.367 djm 1942: }
1943: if ((r = sshbuf_consume(c->output, len)) != 0) {
1944: fatal("%s: channel %d: consume: %s",
1945: __func__, c->self, ssh_err(r));
1.44 markus 1946: }
1.309 djm 1947: out:
1.367 djm 1948: c->local_consumed += olen - sshbuf_len(c->output);
1949:
1950: return 1;
1951: }
1952:
1953: static int
1954: channel_handle_efd_write(struct ssh *ssh, Channel *c,
1955: fd_set *readset, fd_set *writeset)
1956: {
1957: int r;
1958: ssize_t len;
1959:
1960: if (!FD_ISSET(c->efd, writeset) || sshbuf_len(c->extended) == 0)
1961: return 1;
1962:
1963: len = write(c->efd, sshbuf_ptr(c->extended),
1964: sshbuf_len(c->extended));
1965: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1966: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1967: return 1;
1968: if (len <= 0) {
1969: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1970: channel_close_fd(ssh, &c->efd);
1971: } else {
1972: if ((r = sshbuf_consume(c->extended, len)) != 0) {
1973: fatal("%s: channel %d: consume: %s",
1974: __func__, c->self, ssh_err(r));
1975: }
1976: c->local_consumed += len;
1977: }
1.44 markus 1978: return 1;
1979: }
1.241 deraadt 1980:
1.127 itojun 1981: static int
1.367 djm 1982: channel_handle_efd_read(struct ssh *ssh, Channel *c,
1983: fd_set *readset, fd_set *writeset)
1.44 markus 1984: {
1.214 markus 1985: char buf[CHAN_RBUF];
1.367 djm 1986: int r;
1987: ssize_t len;
1988:
1989: if (!FD_ISSET(c->efd, readset))
1990: return 1;
1.44 markus 1991:
1.367 djm 1992: len = read(c->efd, buf, sizeof(buf));
1993: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1994: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1995: return 1;
1996: if (len <= 0) {
1997: debug2("channel %d: closing read-efd %d",
1998: c->self, c->efd);
1999: channel_close_fd(ssh, &c->efd);
2000: } else {
2001: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
2002: debug3("channel %d: discard efd",
2003: c->self);
2004: } else if ((r = sshbuf_put(c->extended, buf, len)) != 0) {
2005: fatal("%s: channel %d: append: %s",
2006: __func__, c->self, ssh_err(r));
1.44 markus 2007: }
2008: }
2009: return 1;
2010: }
1.241 deraadt 2011:
1.127 itojun 2012: static int
1.367 djm 2013: channel_handle_efd(struct ssh *ssh, Channel *c,
2014: fd_set *readset, fd_set *writeset)
1.44 markus 2015: {
1.367 djm 2016: if (c->efd == -1)
2017: return 1;
2018:
2019: /** XXX handle drain efd, too */
2020:
2021: if (c->extended_usage == CHAN_EXTENDED_WRITE)
2022: return channel_handle_efd_write(ssh, c, readset, writeset);
2023: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2024: c->extended_usage == CHAN_EXTENDED_IGNORE)
2025: return channel_handle_efd_read(ssh, c, readset, writeset);
2026:
2027: return 1;
2028: }
2029:
2030: static int
2031: channel_check_window(struct ssh *ssh, Channel *c)
2032: {
2033: int r;
2034:
1.104 markus 2035: if (c->type == SSH_CHANNEL_OPEN &&
2036: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2037: ((c->local_window_max - c->local_window >
1.269 markus 2038: c->local_maxpacket*3) ||
2039: c->local_window < c->local_window_max/2) &&
1.44 markus 2040: c->local_consumed > 0) {
1.368 djm 2041: if (!c->have_remote_id)
2042: fatal(":%s: channel %d: no remote id",
2043: __func__, c->self);
1.367 djm 2044: if ((r = sshpkt_start(ssh,
2045: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2046: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2047: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2048: (r = sshpkt_send(ssh)) != 0) {
2049: fatal("%s: channel %i: %s", __func__,
2050: c->self, ssh_err(r));
2051: }
1.70 markus 2052: debug2("channel %d: window %d sent adjust %d",
1.44 markus 2053: c->self, c->local_window,
2054: c->local_consumed);
2055: c->local_window += c->local_consumed;
2056: c->local_consumed = 0;
1.1 deraadt 2057: }
1.41 markus 2058: return 1;
1.1 deraadt 2059: }
2060:
1.127 itojun 2061: static void
1.367 djm 2062: channel_post_open(struct ssh *ssh, Channel *c,
2063: fd_set *readset, fd_set *writeset)
1.41 markus 2064: {
1.367 djm 2065: channel_handle_rfd(ssh, c, readset, writeset);
2066: channel_handle_wfd(ssh, c, readset, writeset);
2067: channel_handle_efd(ssh, c, readset, writeset);
2068: channel_check_window(ssh, c);
1.44 markus 2069: }
2070:
1.302 djm 2071: static u_int
1.367 djm 2072: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2073: {
2074: char buf[CHAN_RBUF];
1.367 djm 2075: ssize_t len;
1.302 djm 2076: u_int rlen;
1.367 djm 2077: int r;
1.302 djm 2078:
1.367 djm 2079: if (sshbuf_len(c->input) < need) {
2080: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2081: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.349 naddy 2082: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2083: return sshbuf_len(c->input);
1.302 djm 2084: if (len <= 0) {
1.367 djm 2085: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2086: c->self, c->rfd, len);
1.367 djm 2087: chan_read_failed(ssh, c);
1.349 naddy 2088: return 0;
1.367 djm 2089: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
2090: fatal("%s: channel %d: append: %s",
2091: __func__, c->self, ssh_err(r));
2092: }
1.302 djm 2093: }
1.367 djm 2094: return sshbuf_len(c->input);
1.302 djm 2095: }
2096:
2097: static void
1.367 djm 2098: channel_post_mux_client_read(struct ssh *ssh, Channel *c,
2099: fd_set *readset, fd_set *writeset)
1.302 djm 2100: {
2101: u_int need;
2102:
1.367 djm 2103: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
2104: return;
2105: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2106: return;
2107: if (c->mux_pause)
2108: return;
2109:
2110: /*
2111: * Don't not read past the precise end of packets to
2112: * avoid disrupting fd passing.
2113: */
2114: if (read_mux(ssh, c, 4) < 4) /* read header */
2115: return;
2116: /* XXX sshbuf_peek_u32 */
2117: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2118: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2119: if (need > CHANNEL_MUX_MAX_PACKET) {
2120: debug2("channel %d: packet too big %u > %u",
2121: c->self, CHANNEL_MUX_MAX_PACKET, need);
2122: chan_rcvd_oclose(ssh, c);
2123: return;
2124: }
2125: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2126: return;
2127: if (c->mux_rcb(ssh, c) != 0) {
2128: debug("channel %d: mux_rcb failed", c->self);
2129: chan_mark_dead(ssh, c);
2130: return;
1.302 djm 2131: }
1.367 djm 2132: }
2133:
2134: static void
2135: channel_post_mux_client_write(struct ssh *ssh, Channel *c,
2136: fd_set *readset, fd_set *writeset)
2137: {
2138: ssize_t len;
2139: int r;
1.302 djm 2140:
1.367 djm 2141: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
2142: sshbuf_len(c->output) == 0)
2143: return;
2144:
2145: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
2146: if (len < 0 && (errno == EINTR || errno == EAGAIN))
2147: return;
2148: if (len <= 0) {
2149: chan_mark_dead(ssh, c);
2150: return;
1.302 djm 2151: }
1.367 djm 2152: if ((r = sshbuf_consume(c->output, len)) != 0)
2153: fatal("%s: channel %d: consume: %s", __func__,
2154: c->self, ssh_err(r));
2155: }
2156:
2157: static void
2158: channel_post_mux_client(struct ssh *ssh, Channel *c,
2159: fd_set *readset, fd_set *writeset)
2160: {
2161: channel_post_mux_client_read(ssh, c, readset, writeset);
2162: channel_post_mux_client_write(ssh, c, readset, writeset);
1.302 djm 2163: }
2164:
2165: static void
1.367 djm 2166: channel_post_mux_listener(struct ssh *ssh, Channel *c,
2167: fd_set *readset, fd_set *writeset)
1.302 djm 2168: {
2169: Channel *nc;
2170: struct sockaddr_storage addr;
2171: socklen_t addrlen;
2172: int newsock;
2173: uid_t euid;
2174: gid_t egid;
2175:
2176: if (!FD_ISSET(c->sock, readset))
2177: return;
2178:
2179: debug("multiplexing control connection");
2180:
2181: /*
2182: * Accept connection on control socket
2183: */
2184: memset(&addr, 0, sizeof(addr));
2185: addrlen = sizeof(addr);
2186: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2187: &addrlen)) == -1) {
2188: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 2189: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2190: c->notbefore = monotime() + 1;
1.302 djm 2191: return;
2192: }
2193:
2194: if (getpeereid(newsock, &euid, &egid) < 0) {
2195: error("%s getpeereid failed: %s", __func__,
2196: strerror(errno));
2197: close(newsock);
2198: return;
2199: }
2200: if ((euid != 0) && (getuid() != euid)) {
2201: error("multiplex uid mismatch: peer euid %u != uid %u",
2202: (u_int)euid, (u_int)getuid());
2203: close(newsock);
2204: return;
2205: }
1.367 djm 2206: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2207: newsock, newsock, -1, c->local_window_max,
2208: c->local_maxpacket, 0, "mux-control", 1);
2209: nc->mux_rcb = c->mux_rcb;
1.367 djm 2210: debug3("%s: new mux channel %d fd %d", __func__, nc->self, nc->sock);
1.302 djm 2211: /* establish state */
1.367 djm 2212: nc->mux_rcb(ssh, nc);
1.302 djm 2213: /* mux state transitions must not elicit protocol messages */
2214: nc->flags |= CHAN_LOCAL;
2215: }
2216:
1.127 itojun 2217: static void
1.367 djm 2218: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2219: {
1.367 djm 2220: chan_fn **pre, **post;
2221:
2222: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
2223: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
2224: fatal("%s: allocation failed", __func__);
2225:
2226: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2227: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2228: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2229: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2230: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2231: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2232: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2233: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2234: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2235: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2236: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2237: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2238: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2239:
2240: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2241: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2242: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2243: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2244: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2245: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2246: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2247: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2248: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2249: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2250: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2251: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2252:
1.367 djm 2253: sc->channel_pre = pre;
2254: sc->channel_post = post;
1.44 markus 2255: }
2256:
1.140 markus 2257: /* gc dead channels */
2258: static void
1.367 djm 2259: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2260: {
2261: if (c == NULL)
2262: return;
2263: if (c->detach_user != NULL) {
1.367 djm 2264: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2265: return;
1.194 markus 2266: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2267: c->detach_user(ssh, c->self, NULL);
1.140 markus 2268: /* if we still have a callback */
2269: if (c->detach_user != NULL)
2270: return;
1.194 markus 2271: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2272: }
1.367 djm 2273: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2274: return;
1.194 markus 2275: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2276: channel_free(ssh, c);
1.140 markus 2277: }
2278:
1.367 djm 2279: enum channel_table { CHAN_PRE, CHAN_POST };
2280:
1.127 itojun 2281: static void
1.367 djm 2282: channel_handler(struct ssh *ssh, int table,
1.366 djm 2283: fd_set *readset, fd_set *writeset, time_t *unpause_secs)
1.41 markus 2284: {
1.367 djm 2285: struct ssh_channels *sc = ssh->chanctxt;
2286: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2287: u_int i, oalloc;
1.41 markus 2288: Channel *c;
1.317 djm 2289: time_t now;
1.25 markus 2290:
1.322 dtucker 2291: now = monotime();
1.317 djm 2292: if (unpause_secs != NULL)
2293: *unpause_secs = 0;
1.367 djm 2294: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2295: c = sc->channels[i];
1.113 markus 2296: if (c == NULL)
1.41 markus 2297: continue;
1.299 markus 2298: if (c->delayed) {
1.367 djm 2299: if (table == CHAN_PRE)
1.299 markus 2300: c->delayed = 0;
2301: else
2302: continue;
2303: }
1.317 djm 2304: if (ftab[c->type] != NULL) {
2305: /*
2306: * Run handlers that are not paused.
2307: */
2308: if (c->notbefore <= now)
1.367 djm 2309: (*ftab[c->type])(ssh, c, readset, writeset);
1.317 djm 2310: else if (unpause_secs != NULL) {
2311: /*
2312: * Collect the time that the earliest
2313: * channel comes off pause.
2314: */
2315: debug3("%s: chan %d: skip for %d more seconds",
2316: __func__, c->self,
2317: (int)(c->notbefore - now));
2318: if (*unpause_secs == 0 ||
2319: (c->notbefore - now) < *unpause_secs)
2320: *unpause_secs = c->notbefore - now;
2321: }
2322: }
1.367 djm 2323: channel_garbage_collect(ssh, c);
1.1 deraadt 2324: }
1.317 djm 2325: if (unpause_secs != NULL && *unpause_secs != 0)
2326: debug3("%s: first channel unpauses in %d seconds",
2327: __func__, (int)*unpause_secs);
1.1 deraadt 2328: }
2329:
1.121 markus 2330: /*
1.372 markus 2331: * Create sockets before allocating the select bitmasks.
2332: * This is necessary for things that need to happen after reading
2333: * the network-input but before channel_prepare_select().
2334: */
2335: static void
2336: channel_before_prepare_select(struct ssh *ssh)
2337: {
2338: struct ssh_channels *sc = ssh->chanctxt;
2339: Channel *c;
2340: u_int i, oalloc;
2341:
2342: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2343: c = sc->channels[i];
2344: if (c == NULL)
2345: continue;
2346: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
2347: channel_before_prepare_select_rdynamic(ssh, c);
2348: }
2349: }
2350:
2351: /*
1.121 markus 2352: * Allocate/update select bitmasks and add any bits relevant to channels in
2353: * select bitmasks.
2354: */
1.49 markus 2355: void
1.366 djm 2356: channel_prepare_select(struct ssh *ssh, fd_set **readsetp, fd_set **writesetp,
2357: int *maxfdp, u_int *nallocp, time_t *minwait_secs)
1.41 markus 2358: {
1.243 djm 2359: u_int n, sz, nfdset;
1.84 markus 2360:
1.372 markus 2361: channel_before_prepare_select(ssh); /* might update channel_max_fd */
2362:
1.367 djm 2363: n = MAXIMUM(*maxfdp, ssh->chanctxt->channel_max_fd);
1.84 markus 2364:
1.243 djm 2365: nfdset = howmany(n+1, NFDBITS);
2366: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2367: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2368: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2369: sz = nfdset * sizeof(fd_mask);
2370:
1.132 markus 2371: /* perhaps check sz < nalloc/2 and shrink? */
2372: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2373: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2374: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2375: *nallocp = sz;
1.84 markus 2376: }
1.132 markus 2377: *maxfdp = n;
1.84 markus 2378: memset(*readsetp, 0, sz);
2379: memset(*writesetp, 0, sz);
2380:
1.366 djm 2381: if (!ssh_packet_is_rekeying(ssh))
1.367 djm 2382: channel_handler(ssh, CHAN_PRE, *readsetp, *writesetp,
1.317 djm 2383: minwait_secs);
1.41 markus 2384: }
2385:
1.121 markus 2386: /*
2387: * After select, perform any appropriate operations for channels which have
2388: * events pending.
2389: */
1.49 markus 2390: void
1.366 djm 2391: channel_after_select(struct ssh *ssh, fd_set *readset, fd_set *writeset)
1.41 markus 2392: {
1.367 djm 2393: channel_handler(ssh, CHAN_POST, readset, writeset, NULL);
2394: }
2395:
2396: /*
2397: * Enqueue data for channels with open or draining c->input.
2398: */
2399: static void
2400: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2401: {
1.373 djm 2402: size_t len, plen;
2403: const u_char *pkt;
1.367 djm 2404: int r;
2405:
2406: if ((len = sshbuf_len(c->input)) == 0) {
2407: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2408: /*
2409: * input-buffer is empty and read-socket shutdown:
2410: * tell peer, that we will not send more data:
2411: * send IEOF.
2412: * hack for extended data: delay EOF if EFD still
2413: * in use.
2414: */
2415: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2416: debug2("channel %d: "
2417: "ibuf_empty delayed efd %d/(%zu)",
2418: c->self, c->efd, sshbuf_len(c->extended));
2419: else
2420: chan_ibuf_empty(ssh, c);
2421: }
2422: return;
2423: }
2424:
1.368 djm 2425: if (!c->have_remote_id)
2426: fatal(":%s: channel %d: no remote id", __func__, c->self);
2427:
1.367 djm 2428: if (c->datagram) {
2429: /* Check datagram will fit; drop if not */
1.373 djm 2430: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
2431: fatal("%s: channel %d: get datagram: %s", __func__,
1.367 djm 2432: c->self, ssh_err(r));
2433: /*
2434: * XXX this does tail-drop on the datagram queue which is
2435: * usually suboptimal compared to head-drop. Better to have
2436: * backpressure at read time? (i.e. read + discard)
2437: */
1.373 djm 2438: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2439: debug("channel %d: datagram too big", c->self);
2440: return;
2441: }
2442: /* Enqueue it */
2443: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2444: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2445: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.367 djm 2446: (r = sshpkt_send(ssh)) != 0) {
2447: fatal("%s: channel %i: datagram: %s", __func__,
2448: c->self, ssh_err(r));
2449: }
1.373 djm 2450: c->remote_window -= plen;
1.367 djm 2451: return;
2452: }
2453:
2454: /* Enqueue packet for buffered data. */
2455: if (len > c->remote_window)
2456: len = c->remote_window;
2457: if (len > c->remote_maxpacket)
2458: len = c->remote_maxpacket;
2459: if (len == 0)
2460: return;
2461: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2462: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2463: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
2464: (r = sshpkt_send(ssh)) != 0) {
2465: fatal("%s: channel %i: data: %s", __func__,
2466: c->self, ssh_err(r));
2467: }
2468: if ((r = sshbuf_consume(c->input, len)) != 0)
2469: fatal("%s: channel %i: consume: %s", __func__,
2470: c->self, ssh_err(r));
2471: c->remote_window -= len;
1.41 markus 2472: }
2473:
1.367 djm 2474: /*
2475: * Enqueue data for channels with open c->extended in read mode.
2476: */
2477: static void
2478: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2479: {
2480: size_t len;
2481: int r;
2482:
2483: if ((len = sshbuf_len(c->extended)) == 0)
2484: return;
2485:
2486: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2487: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2488: if (len > c->remote_window)
2489: len = c->remote_window;
2490: if (len > c->remote_maxpacket)
2491: len = c->remote_maxpacket;
2492: if (len == 0)
2493: return;
1.368 djm 2494: if (!c->have_remote_id)
2495: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.367 djm 2496: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2497: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2498: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2499: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
2500: (r = sshpkt_send(ssh)) != 0) {
2501: fatal("%s: channel %i: data: %s", __func__,
2502: c->self, ssh_err(r));
2503: }
2504: if ((r = sshbuf_consume(c->extended, len)) != 0)
2505: fatal("%s: channel %i: consume: %s", __func__,
2506: c->self, ssh_err(r));
2507: c->remote_window -= len;
2508: debug2("channel %d: sent ext data %zu", c->self, len);
2509: }
1.121 markus 2510:
1.84 markus 2511: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2512: void
1.367 djm 2513: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2514: {
1.367 djm 2515: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2516: Channel *c;
1.367 djm 2517: u_int i;
1.1 deraadt 2518:
1.367 djm 2519: for (i = 0; i < sc->channels_alloc; i++) {
2520: c = sc->channels[i];
1.113 markus 2521: if (c == NULL)
2522: continue;
1.37 markus 2523:
1.121 markus 2524: /*
2525: * We are only interested in channels that can have buffered
2526: * incoming data.
2527: */
1.358 djm 2528: if (c->type != SSH_CHANNEL_OPEN)
2529: continue;
2530: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2531: /* XXX is this true? */
1.367 djm 2532: debug3("channel %d: will not send data after close",
2533: c->self);
1.44 markus 2534: continue;
2535: }
1.25 markus 2536:
2537: /* Get the amount of buffered data for this channel. */
1.367 djm 2538: if (c->istate == CHAN_INPUT_OPEN ||
2539: c->istate == CHAN_INPUT_WAIT_DRAIN)
2540: channel_output_poll_input_open(ssh, c);
1.44 markus 2541: /* Send extended data, i.e. stderr */
1.358 djm 2542: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2543: c->extended_usage == CHAN_EXTENDED_READ)
2544: channel_output_poll_extended_read(ssh, c);
1.25 markus 2545: }
1.1 deraadt 2546: }
2547:
1.354 markus 2548: /* -- mux proxy support */
2549:
2550: /*
2551: * When multiplexing channel messages for mux clients we have to deal
2552: * with downstream messages from the mux client and upstream messages
2553: * from the ssh server:
2554: * 1) Handling downstream messages is straightforward and happens
2555: * in channel_proxy_downstream():
2556: * - We forward all messages (mostly) unmodified to the server.
2557: * - However, in order to route messages from upstream to the correct
2558: * downstream client, we have to replace the channel IDs used by the
2559: * mux clients with a unique channel ID because the mux clients might
2560: * use conflicting channel IDs.
2561: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2562: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2563: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2564: * with the newly allocated channel ID.
2565: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
2566: * channels and procesed by channel_proxy_upstream(). The local channel ID
2567: * is then translated back to the original mux client ID.
2568: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2569: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2570: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2571: * downstream mux client are removed.
2572: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2573: * requires more work, because they are not addressed to a specific
2574: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2575: * out whether the request is addressed to the local client or a
2576: * specific downstream client based on the listen-address/port.
2577: * 6) Agent and X11-Forwarding have a similar problem and are currenly
2578: * not supported as the matching session/channel cannot be identified
2579: * easily.
2580: */
2581:
2582: /*
2583: * receive packets from downstream mux clients:
2584: * channel callback fired on read from mux client, creates
2585: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2586: * on channel creation.
2587: */
2588: int
1.367 djm 2589: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2590: {
2591: Channel *c = NULL;
2592: struct sshbuf *original = NULL, *modified = NULL;
2593: const u_char *cp;
2594: char *ctype = NULL, *listen_host = NULL;
2595: u_char type;
2596: size_t have;
1.370 djm 2597: int ret = -1, r;
1.355 djm 2598: u_int id, remote_id, listen_port;
1.354 markus 2599:
1.367 djm 2600: /* sshbuf_dump(downstream->input, stderr); */
2601: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2602: != 0) {
2603: error("%s: malformed message: %s", __func__, ssh_err(r));
2604: return -1;
2605: }
2606: if (have < 2) {
2607: error("%s: short message", __func__);
2608: return -1;
2609: }
2610: type = cp[1];
2611: /* skip padlen + type */
2612: cp += 2;
2613: have -= 2;
2614: if (ssh_packet_log_type(type))
2615: debug3("%s: channel %u: down->up: type %u", __func__,
2616: downstream->self, type);
2617:
2618: switch (type) {
2619: case SSH2_MSG_CHANNEL_OPEN:
2620: if ((original = sshbuf_from(cp, have)) == NULL ||
2621: (modified = sshbuf_new()) == NULL) {
2622: error("%s: alloc", __func__);
2623: goto out;
2624: }
2625: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2626: (r = sshbuf_get_u32(original, &id)) != 0) {
2627: error("%s: parse error %s", __func__, ssh_err(r));
2628: goto out;
2629: }
1.367 djm 2630: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2631: -1, -1, -1, 0, 0, 0, ctype, 1);
2632: c->mux_ctx = downstream; /* point to mux client */
2633: c->mux_downstream_id = id; /* original downstream id */
2634: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2635: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2636: (r = sshbuf_putb(modified, original)) != 0) {
2637: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2638: channel_free(ssh, c);
1.354 markus 2639: goto out;
2640: }
2641: break;
2642: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2643: /*
2644: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2645: * need to parse 'remote_id' instead of 'ctype'.
2646: */
2647: if ((original = sshbuf_from(cp, have)) == NULL ||
2648: (modified = sshbuf_new()) == NULL) {
2649: error("%s: alloc", __func__);
2650: goto out;
2651: }
2652: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2653: (r = sshbuf_get_u32(original, &id)) != 0) {
2654: error("%s: parse error %s", __func__, ssh_err(r));
2655: goto out;
2656: }
1.367 djm 2657: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2658: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
2659: c->mux_ctx = downstream; /* point to mux client */
2660: c->mux_downstream_id = id;
2661: c->remote_id = remote_id;
1.368 djm 2662: c->have_remote_id = 1;
1.354 markus 2663: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2664: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2665: (r = sshbuf_putb(modified, original)) != 0) {
2666: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2667: channel_free(ssh, c);
1.354 markus 2668: goto out;
2669: }
2670: break;
2671: case SSH2_MSG_GLOBAL_REQUEST:
2672: if ((original = sshbuf_from(cp, have)) == NULL) {
2673: error("%s: alloc", __func__);
2674: goto out;
2675: }
2676: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
2677: error("%s: parse error %s", __func__, ssh_err(r));
2678: goto out;
2679: }
2680: if (strcmp(ctype, "tcpip-forward") != 0) {
2681: error("%s: unsupported request %s", __func__, ctype);
2682: goto out;
2683: }
2684: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2685: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2686: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
2687: error("%s: parse error %s", __func__, ssh_err(r));
2688: goto out;
2689: }
1.355 djm 2690: if (listen_port > 65535) {
2691: error("%s: tcpip-forward for %s: bad port %u",
2692: __func__, listen_host, listen_port);
2693: goto out;
2694: }
1.354 markus 2695: /* Record that connection to this host/port is permitted. */
1.370 djm 2696: fwd_perm_list_add(ssh, FWDPERM_USER, "<mux>", -1,
1.367 djm 2697: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 2698: listen_host = NULL;
2699: break;
2700: case SSH2_MSG_CHANNEL_CLOSE:
2701: if (have < 4)
2702: break;
2703: remote_id = PEEK_U32(cp);
1.367 djm 2704: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 2705: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 2706: channel_free(ssh, c);
1.354 markus 2707: else
2708: c->flags |= CHAN_CLOSE_SENT;
2709: }
2710: break;
2711: }
2712: if (modified) {
2713: if ((r = sshpkt_start(ssh, type)) != 0 ||
2714: (r = sshpkt_putb(ssh, modified)) != 0 ||
2715: (r = sshpkt_send(ssh)) != 0) {
2716: error("%s: send %s", __func__, ssh_err(r));
2717: goto out;
2718: }
2719: } else {
2720: if ((r = sshpkt_start(ssh, type)) != 0 ||
2721: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2722: (r = sshpkt_send(ssh)) != 0) {
2723: error("%s: send %s", __func__, ssh_err(r));
2724: goto out;
2725: }
2726: }
2727: ret = 0;
2728: out:
2729: free(ctype);
2730: free(listen_host);
2731: sshbuf_free(original);
2732: sshbuf_free(modified);
2733: return ret;
2734: }
2735:
2736: /*
2737: * receive packets from upstream server and de-multiplex packets
2738: * to correct downstream:
2739: * implemented as a helper for channel input handlers,
2740: * replaces local (proxy) channel ID with downstream channel ID.
2741: */
2742: int
1.363 markus 2743: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 2744: {
2745: struct sshbuf *b = NULL;
2746: Channel *downstream;
2747: const u_char *cp = NULL;
2748: size_t len;
2749: int r;
2750:
2751: /*
2752: * When receiving packets from the peer we need to check whether we
2753: * need to forward the packets to the mux client. In this case we
2754: * restore the orignal channel id and keep track of CLOSE messages,
2755: * so we can cleanup the channel.
2756: */
2757: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2758: return 0;
2759: if ((downstream = c->mux_ctx) == NULL)
2760: return 0;
2761: switch (type) {
2762: case SSH2_MSG_CHANNEL_CLOSE:
2763: case SSH2_MSG_CHANNEL_DATA:
2764: case SSH2_MSG_CHANNEL_EOF:
2765: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2766: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2767: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2768: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2769: case SSH2_MSG_CHANNEL_SUCCESS:
2770: case SSH2_MSG_CHANNEL_FAILURE:
2771: case SSH2_MSG_CHANNEL_REQUEST:
2772: break;
2773: default:
2774: debug2("%s: channel %u: unsupported type %u", __func__,
2775: c->self, type);
2776: return 0;
2777: }
2778: if ((b = sshbuf_new()) == NULL) {
2779: error("%s: alloc reply", __func__);
2780: goto out;
2781: }
2782: /* get remaining payload (after id) */
2783: cp = sshpkt_ptr(ssh, &len);
2784: if (cp == NULL) {
2785: error("%s: no packet", __func__);
2786: goto out;
2787: }
2788: /* translate id and send to muxclient */
2789: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2790: (r = sshbuf_put_u8(b, type)) != 0 ||
2791: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2792: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 2793: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.354 markus 2794: error("%s: compose for muxclient %s", __func__, ssh_err(r));
2795: goto out;
2796: }
2797: /* sshbuf_dump(b, stderr); */
2798: if (ssh_packet_log_type(type))
2799: debug3("%s: channel %u: up->down: type %u", __func__, c->self,
2800: type);
2801: out:
2802: /* update state */
2803: switch (type) {
2804: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2805: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 2806: if (cp && len > 4) {
1.354 markus 2807: c->remote_id = PEEK_U32(cp);
1.368 djm 2808: c->have_remote_id = 1;
2809: }
1.354 markus 2810: break;
2811: case SSH2_MSG_CHANNEL_CLOSE:
2812: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 2813: channel_free(ssh, c);
1.354 markus 2814: else
2815: c->flags |= CHAN_CLOSE_RCVD;
2816: break;
2817: }
2818: sshbuf_free(b);
2819: return 1;
2820: }
1.121 markus 2821:
2822: /* -- protocol input */
1.249 djm 2823:
1.367 djm 2824: /* Parse a channel ID from the current packet */
2825: static int
2826: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
2827: {
2828: u_int32_t id;
2829: int r;
2830:
2831: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
2832: error("%s: parse id: %s", where, ssh_err(r));
2833: ssh_packet_disconnect(ssh, "Invalid %s message", what);
2834: }
2835: if (id > INT_MAX) {
2836: error("%s: bad channel id %u: %s", where, id, ssh_err(r));
2837: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
2838: }
2839: return (int)id;
2840: }
2841:
2842: /* Lookup a channel from an ID in the current packet */
2843: static Channel *
2844: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
2845: {
2846: int id = channel_parse_id(ssh, where, what);
2847: Channel *c;
2848:
2849: if ((c = channel_lookup(ssh, id)) == NULL) {
2850: ssh_packet_disconnect(ssh,
2851: "%s packet referred to nonexistent channel %d", what, id);
2852: }
2853: return c;
2854: }
2855:
1.339 markus 2856: int
1.363 markus 2857: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2858: {
1.332 djm 2859: const u_char *data;
1.367 djm 2860: size_t data_len, win_len;
2861: Channel *c = channel_from_packet_id(ssh, __func__, "data");
2862: int r;
1.25 markus 2863:
1.363 markus 2864: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2865: return 0;
1.25 markus 2866:
2867: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2868: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 2869: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
2870: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 2871: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2872: return 0;
1.37 markus 2873:
1.25 markus 2874: /* Get the data. */
1.367 djm 2875: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0)
2876: fatal("%s: channel %d: get data: %s", __func__,
2877: c->self, ssh_err(r));
2878: ssh_packet_check_eom(ssh);
2879:
1.309 djm 2880: win_len = data_len;
2881: if (c->datagram)
2882: win_len += 4; /* string length header */
1.200 markus 2883:
2884: /*
1.367 djm 2885: * The sending side reduces its window as it sends data, so we
2886: * must 'fake' consumption of the data in order to ensure that window
2887: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 2888: */
1.358 djm 2889: if (c->ostate != CHAN_OUTPUT_OPEN) {
2890: c->local_window -= win_len;
2891: c->local_consumed += win_len;
1.339 markus 2892: return 0;
1.200 markus 2893: }
1.41 markus 2894:
1.358 djm 2895: if (win_len > c->local_maxpacket) {
1.367 djm 2896: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 2897: c->self, win_len, c->local_maxpacket);
1.367 djm 2898: return 0;
1.358 djm 2899: }
2900: if (win_len > c->local_window) {
1.367 djm 2901: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 2902: c->self, win_len, c->local_window);
2903: return 0;
1.44 markus 2904: }
1.358 djm 2905: c->local_window -= win_len;
2906:
1.367 djm 2907: if (c->datagram) {
2908: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
2909: fatal("%s: channel %d: append datagram: %s",
2910: __func__, c->self, ssh_err(r));
2911: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
2912: fatal("%s: channel %d: append data: %s",
2913: __func__, c->self, ssh_err(r));
2914:
1.339 markus 2915: return 0;
1.1 deraadt 2916: }
1.121 markus 2917:
1.339 markus 2918: int
1.363 markus 2919: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 2920: {
1.367 djm 2921: const u_char *data;
2922: size_t data_len;
2923: u_int32_t tcode;
2924: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
2925: int r;
1.44 markus 2926:
1.363 markus 2927: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2928: return 0;
1.44 markus 2929: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 2930: logit("channel %d: ext data for non open", c->self);
1.339 markus 2931: return 0;
1.172 markus 2932: }
2933: if (c->flags & CHAN_EOF_RCVD) {
2934: if (datafellows & SSH_BUG_EXTEOF)
1.367 djm 2935: debug("channel %d: accepting ext data after eof",
2936: c->self);
1.172 markus 2937: else
1.367 djm 2938: ssh_packet_disconnect(ssh, "Received extended_data "
2939: "after EOF on channel %d.", c->self);
2940: }
2941:
2942: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
2943: error("%s: parse tcode: %s", __func__, ssh_err(r));
2944: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 2945: }
2946: if (c->efd == -1 ||
2947: c->extended_usage != CHAN_EXTENDED_WRITE ||
2948: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2949: logit("channel %d: bad ext data", c->self);
1.339 markus 2950: return 0;
1.44 markus 2951: }
1.367 djm 2952: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0) {
2953: error("%s: parse data: %s", __func__, ssh_err(r));
2954: ssh_packet_disconnect(ssh, "Invalid extended_data message");
2955: }
2956: ssh_packet_check_eom(ssh);
2957:
1.44 markus 2958: if (data_len > c->local_window) {
1.367 djm 2959: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 2960: c->self, data_len, c->local_window);
1.339 markus 2961: return 0;
1.44 markus 2962: }
1.367 djm 2963: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
2964: /* XXX sshpkt_getb? */
2965: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
2966: error("%s: append: %s", __func__, ssh_err(r));
1.44 markus 2967: c->local_window -= data_len;
1.339 markus 2968: return 0;
1.44 markus 2969: }
2970:
1.339 markus 2971: int
1.363 markus 2972: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 2973: {
1.367 djm 2974: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
2975:
2976: ssh_packet_check_eom(ssh);
1.41 markus 2977:
1.363 markus 2978: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2979: return 0;
1.367 djm 2980: chan_rcvd_ieof(ssh, c);
1.133 markus 2981:
2982: /* XXX force input close */
1.156 markus 2983: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2984: debug("channel %d: FORCE input drain", c->self);
2985: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 2986: if (sshbuf_len(c->input) == 0)
2987: chan_ibuf_empty(ssh, c);
1.133 markus 2988: }
1.339 markus 2989: return 0;
1.41 markus 2990: }
1.1 deraadt 2991:
1.339 markus 2992: int
1.363 markus 2993: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 2994: {
1.367 djm 2995: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.151 markus 2996:
1.363 markus 2997: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2998: return 0;
1.367 djm 2999: ssh_packet_check_eom(ssh);
3000: chan_rcvd_oclose(ssh, c);
1.339 markus 3001: return 0;
1.1 deraadt 3002: }
3003:
1.339 markus 3004: int
1.363 markus 3005: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3006: {
1.367 djm 3007: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3008: u_int32_t remote_window, remote_maxpacket;
3009: int r;
1.25 markus 3010:
1.363 markus 3011: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3012: return 0;
3013: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 3014: packet_disconnect("Received open confirmation for "
1.367 djm 3015: "non-opening channel %d.", c->self);
3016: /*
3017: * Record the remote channel number and mark that the channel
3018: * is now open.
3019: */
1.368 djm 3020: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3021: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.367 djm 3022: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0) {
3023: error("%s: window/maxpacket: %s", __func__, ssh_err(r));
3024: packet_disconnect("Invalid open confirmation message");
3025: }
3026: ssh_packet_check_eom(ssh);
3027:
1.368 djm 3028: c->have_remote_id = 1;
1.367 djm 3029: c->remote_window = remote_window;
3030: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3031: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3032: if (c->open_confirm) {
1.367 djm 3033: debug2("%s: channel %d: callback start", __func__, c->self);
3034: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
3035: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3036: }
1.358 djm 3037: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3038: c->remote_window, c->remote_maxpacket);
1.339 markus 3039: return 0;
1.1 deraadt 3040: }
3041:
1.127 itojun 3042: static char *
1.114 markus 3043: reason2txt(int reason)
3044: {
1.143 deraadt 3045: switch (reason) {
1.114 markus 3046: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3047: return "administratively prohibited";
3048: case SSH2_OPEN_CONNECT_FAILED:
3049: return "connect failed";
3050: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3051: return "unknown channel type";
3052: case SSH2_OPEN_RESOURCE_SHORTAGE:
3053: return "resource shortage";
3054: }
1.117 stevesk 3055: return "unknown reason";
1.114 markus 3056: }
3057:
1.339 markus 3058: int
1.363 markus 3059: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3060: {
1.367 djm 3061: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3062: u_int32_t reason;
3063: char *msg = NULL;
3064: int r;
1.25 markus 3065:
1.363 markus 3066: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3067: return 0;
3068: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 3069: packet_disconnect("Received open failure for "
1.367 djm 3070: "non-opening channel %d.", c->self);
3071: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
3072: error("%s: reason: %s", __func__, ssh_err(r));
3073: packet_disconnect("Invalid open failure message");
3074: }
1.378 ! djm 3075: /* skip language */
! 3076: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
! 3077: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0) {
! 3078: error("%s: message/lang: %s", __func__, ssh_err(r));
! 3079: packet_disconnect("Invalid open failure message");
1.358 djm 3080: }
1.367 djm 3081: ssh_packet_check_eom(ssh);
3082: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3083: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3084: free(msg);
3085: if (c->open_confirm) {
1.367 djm 3086: debug2("%s: channel %d: callback start", __func__, c->self);
3087: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
3088: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3089: }
1.291 djm 3090: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3091: chan_mark_dead(ssh, c);
1.339 markus 3092: return 0;
1.44 markus 3093: }
3094:
1.339 markus 3095: int
1.363 markus 3096: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3097: {
1.367 djm 3098: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3099: Channel *c;
1.367 djm 3100: u_int32_t adjust;
3101: u_int new_rwin;
3102: int r;
1.1 deraadt 3103:
1.367 djm 3104: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3105: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3106: return 0;
1.372 markus 3107: }
1.367 djm 3108:
1.363 markus 3109: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3110: return 0;
1.367 djm 3111: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0) {
3112: error("%s: adjust: %s", __func__, ssh_err(r));
3113: packet_disconnect("Invalid window adjust message");
3114: }
3115: ssh_packet_check_eom(ssh);
3116: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3117: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3118: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3119: c->self, adjust, c->remote_window);
3120: }
3121: c->remote_window = new_rwin;
1.339 markus 3122: return 0;
1.121 markus 3123: }
1.1 deraadt 3124:
1.339 markus 3125: int
1.363 markus 3126: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3127: {
1.367 djm 3128: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3129: Channel *c;
3130: struct channel_confirm *cc;
3131:
3132: /* Reset keepalive timeout */
1.296 andreas 3133: packet_set_alive_timeouts(0);
1.275 djm 3134:
1.367 djm 3135: debug2("%s: type %d id %d", __func__, type, id);
1.275 djm 3136:
1.367 djm 3137: if ((c = channel_lookup(ssh, id)) == NULL) {
3138: logit("%s: %d: unknown", __func__, id);
1.339 markus 3139: return 0;
1.367 djm 3140: }
1.363 markus 3141: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3142: return 0;
1.367 djm 3143: ssh_packet_check_eom(ssh);
1.275 djm 3144: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3145: return 0;
1.367 djm 3146: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3147: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 3148: explicit_bzero(cc, sizeof(*cc));
1.321 djm 3149: free(cc);
1.339 markus 3150: return 0;
1.275 djm 3151: }
1.121 markus 3152:
3153: /* -- tcp forwarding */
1.135 markus 3154:
3155: void
1.367 djm 3156: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3157: {
1.367 djm 3158: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3159: }
1.121 markus 3160:
1.312 djm 3161:
3162: /*
3163: * Determine whether or not a port forward listens to loopback, the
3164: * specified address or wildcard. On the client, a specified bind
3165: * address will always override gateway_ports. On the server, a
3166: * gateway_ports of 1 (``yes'') will override the client's specification
3167: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3168: * will bind to whatever address the client asked for.
3169: *
3170: * Special-case listen_addrs are:
3171: *
3172: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3173: * "" (empty string), "*" -> wildcard v4/v6
3174: * "localhost" -> loopback v4/v6
1.334 djm 3175: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3176: */
3177: static const char *
3178: channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
1.336 millert 3179: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3180: {
3181: const char *addr = NULL;
3182: int wildcard = 0;
3183:
3184: if (listen_addr == NULL) {
3185: /* No address specified: default to gateway_ports setting */
1.336 millert 3186: if (fwd_opts->gateway_ports)
1.312 djm 3187: wildcard = 1;
1.336 millert 3188: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 3189: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
3190: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3191: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3192: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3193: wildcard = 1;
1.326 djm 3194: /*
3195: * Notify client if they requested a specific listen
3196: * address and it was overridden.
3197: */
3198: if (*listen_addr != '\0' &&
3199: strcmp(listen_addr, "0.0.0.0") != 0 &&
3200: strcmp(listen_addr, "*") != 0) {
3201: packet_send_debug("Forwarding listen address "
3202: "\"%s\" overridden by server "
3203: "GatewayPorts", listen_addr);
3204: }
1.334 djm 3205: } else if (strcmp(listen_addr, "localhost") != 0 ||
3206: strcmp(listen_addr, "127.0.0.1") == 0 ||
3207: strcmp(listen_addr, "::1") == 0) {
3208: /* Accept localhost address when GatewayPorts=yes */
3209: addr = listen_addr;
1.326 djm 3210: }
1.334 djm 3211: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3212: strcmp(listen_addr, "::1") == 0) {
3213: /*
3214: * If a specific IPv4/IPv6 localhost address has been
3215: * requested then accept it even if gateway_ports is in
3216: * effect. This allows the client to prefer IPv4 or IPv6.
3217: */
3218: addr = listen_addr;
1.312 djm 3219: }
3220: if (wildcardp != NULL)
3221: *wildcardp = wildcard;
3222: return addr;
3223: }
3224:
1.160 markus 3225: static int
1.367 djm 3226: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3227: struct Forward *fwd, int *allocated_listen_port,
3228: struct ForwardOptions *fwd_opts)
1.25 markus 3229: {
1.113 markus 3230: Channel *c;
1.226 djm 3231: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3232: struct addrinfo hints, *ai, *aitop;
1.212 djm 3233: const char *host, *addr;
1.35 markus 3234: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3235: in_port_t *lport_p;
1.25 markus 3236:
1.212 djm 3237: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3238:
1.344 millert 3239: if (is_client && fwd->connect_path != NULL) {
3240: host = fwd->connect_path;
3241: } else {
3242: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3243: fwd->listen_host : fwd->connect_host;
3244: if (host == NULL) {
3245: error("No forward host name.");
3246: return 0;
3247: }
3248: if (strlen(host) >= NI_MAXHOST) {
3249: error("Forward host name too long.");
3250: return 0;
3251: }
1.87 markus 3252: }
1.25 markus 3253:
1.312 djm 3254: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.336 millert 3255: addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard,
3256: is_client, fwd_opts);
3257: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 3258: type, wildcard, (addr == NULL) ? "NULL" : addr);
3259:
3260: /*
1.35 markus 3261: * getaddrinfo returns a loopback address if the hostname is
3262: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3263: */
1.35 markus 3264: memset(&hints, 0, sizeof(hints));
1.367 djm 3265: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3266: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3267: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3268: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3269: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3270: if (addr == NULL) {
3271: /* This really shouldn't happen */
3272: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 3273: ssh_gai_strerror(r));
1.212 djm 3274: } else {
1.336 millert 3275: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 3276: ssh_gai_strerror(r));
1.212 djm 3277: }
1.218 markus 3278: return 0;
1.212 djm 3279: }
1.295 djm 3280: if (allocated_listen_port != NULL)
3281: *allocated_listen_port = 0;
1.35 markus 3282: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3283: switch (ai->ai_family) {
3284: case AF_INET:
3285: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3286: sin_port;
3287: break;
3288: case AF_INET6:
3289: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3290: sin6_port;
3291: break;
3292: default:
1.35 markus 3293: continue;
1.295 djm 3294: }
3295: /*
3296: * If allocating a port for -R forwards, then use the
3297: * same port for all address families.
3298: */
1.367 djm 3299: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3300: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3301: *allocated_listen_port > 0)
1.295 djm 3302: *lport_p = htons(*allocated_listen_port);
3303:
1.35 markus 3304: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3305: strport, sizeof(strport),
3306: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 3307: error("%s: getnameinfo failed", __func__);
1.35 markus 3308: continue;
3309: }
3310: /* Create a port to listen for the host. */
1.300 dtucker 3311: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 3312: if (sock < 0) {
3313: /* this is no error since kernel may not support ipv6 */
1.377 djm 3314: verbose("socket [%s]:%s: %.100s", ntop, strport,
3315: strerror(errno));
1.35 markus 3316: continue;
3317: }
1.226 djm 3318:
1.376 djm 3319: set_reuseaddr(sock);
1.182 stevesk 3320:
1.295 djm 3321: debug("Local forwarding listening on %s port %s.",
3322: ntop, strport);
1.35 markus 3323:
3324: /* Bind the socket to the address. */
3325: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.367 djm 3326: /*
3327: * address can be in if use ipv6 address is
3328: * already bound
3329: */
1.377 djm 3330: verbose("bind [%s]:%s: %.100s",
3331: ntop, strport, strerror(errno));
1.35 markus 3332: close(sock);
3333: continue;
3334: }
3335: /* Start listening for connections on the socket. */
1.199 markus 3336: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.377 djm 3337: error("listen [%s]:%s: %.100s", ntop, strport,
3338: strerror(errno));
1.35 markus 3339: close(sock);
3340: continue;
3341: }
1.295 djm 3342:
3343: /*
1.336 millert 3344: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3345: * record what we got.
3346: */
1.367 djm 3347: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3348: fwd->listen_port == 0 &&
1.295 djm 3349: allocated_listen_port != NULL &&
3350: *allocated_listen_port == 0) {
1.350 djm 3351: *allocated_listen_port = get_local_port(sock);
1.295 djm 3352: debug("Allocated listen port %d",
3353: *allocated_listen_port);
3354: }
3355:
1.35 markus 3356: /* Allocate a channel number for the socket. */
1.367 djm 3357: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3358: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3359: 0, "port listener", 1);
1.293 djm 3360: c->path = xstrdup(host);
1.336 millert 3361: c->host_port = fwd->connect_port;
1.312 djm 3362: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3363: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 3364: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
3365: c->listening_port = *allocated_listen_port;
3366: else
1.336 millert 3367: c->listening_port = fwd->listen_port;
1.35 markus 3368: success = 1;
3369: }
3370: if (success == 0)
1.336 millert 3371: error("%s: cannot listen to port: %d", __func__,
3372: fwd->listen_port);
1.35 markus 3373: freeaddrinfo(aitop);
1.87 markus 3374: return success;
1.25 markus 3375: }
1.1 deraadt 3376:
1.336 millert 3377: static int
1.367 djm 3378: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3379: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3380: {
3381: struct sockaddr_un sunaddr;
3382: const char *path;
3383: Channel *c;
3384: int port, sock;
3385: mode_t omask;
3386:
3387: switch (type) {
3388: case SSH_CHANNEL_UNIX_LISTENER:
3389: if (fwd->connect_path != NULL) {
3390: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3391: error("Local connecting path too long: %s",
3392: fwd->connect_path);
3393: return 0;
3394: }
3395: path = fwd->connect_path;
3396: port = PORT_STREAMLOCAL;
3397: } else {
3398: if (fwd->connect_host == NULL) {
3399: error("No forward host name.");
3400: return 0;
3401: }
3402: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3403: error("Forward host name too long.");
3404: return 0;
3405: }
3406: path = fwd->connect_host;
3407: port = fwd->connect_port;
3408: }
3409: break;
3410: case SSH_CHANNEL_RUNIX_LISTENER:
3411: path = fwd->listen_path;
3412: port = PORT_STREAMLOCAL;
3413: break;
3414: default:
3415: error("%s: unexpected channel type %d", __func__, type);
3416: return 0;
3417: }
3418:
3419: if (fwd->listen_path == NULL) {
3420: error("No forward path name.");
3421: return 0;
3422: }
3423: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3424: error("Local listening path too long: %s", fwd->listen_path);
3425: return 0;
3426: }
3427:
3428: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
3429:
3430: /* Start a Unix domain listener. */
3431: omask = umask(fwd_opts->streamlocal_bind_mask);
3432: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3433: fwd_opts->streamlocal_bind_unlink);
3434: umask(omask);
3435: if (sock < 0)
3436: return 0;
3437:
3438: debug("Local forwarding listening on path %s.", fwd->listen_path);
3439:
3440: /* Allocate a channel number for the socket. */
1.367 djm 3441: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3442: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3443: 0, "unix listener", 1);
3444: c->path = xstrdup(path);
3445: c->host_port = port;
3446: c->listening_port = PORT_STREAMLOCAL;
3447: c->listening_addr = xstrdup(fwd->listen_path);
3448: return 1;
3449: }
3450:
3451: static int
1.367 djm 3452: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3453: const char *host, u_short port)
1.202 djm 3454: {
1.209 avsm 3455: u_int i;
3456: int found = 0;
1.202 djm 3457:
1.367 djm 3458: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3459: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3460: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3461: continue;
3462: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3463: debug2("%s: close channel %d", __func__, i);
1.367 djm 3464: channel_free(ssh, c);
1.312 djm 3465: found = 1;
3466: }
3467: }
3468:
1.367 djm 3469: return found;
1.312 djm 3470: }
3471:
1.336 millert 3472: static int
1.367 djm 3473: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3474: {
3475: u_int i;
3476: int found = 0;
3477:
1.367 djm 3478: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3479: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3480: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3481: continue;
3482: if (c->path == NULL)
3483: continue;
3484: if (strcmp(c->path, path) == 0) {
3485: debug2("%s: close channel %d", __func__, i);
1.367 djm 3486: channel_free(ssh, c);
1.336 millert 3487: found = 1;
3488: }
3489: }
3490:
1.367 djm 3491: return found;
1.336 millert 3492: }
3493:
1.312 djm 3494: int
1.367 djm 3495: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3496: {
1.367 djm 3497: if (fwd->listen_path != NULL) {
3498: return channel_cancel_rport_listener_streamlocal(ssh,
3499: fwd->listen_path);
3500: } else {
3501: return channel_cancel_rport_listener_tcpip(ssh,
3502: fwd->listen_host, fwd->listen_port);
3503: }
1.336 millert 3504: }
3505:
3506: static int
1.367 djm 3507: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3508: const char *lhost, u_short lport, int cport,
3509: struct ForwardOptions *fwd_opts)
1.312 djm 3510: {
3511: u_int i;
3512: int found = 0;
1.336 millert 3513: const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts);
1.202 djm 3514:
1.367 djm 3515: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3516: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3517: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3518: continue;
1.313 markus 3519: if (c->listening_port != lport)
1.312 djm 3520: continue;
1.313 markus 3521: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3522: /* skip dynamic forwardings */
3523: if (c->host_port == 0)
3524: continue;
3525: } else {
3526: if (c->host_port != cport)
3527: continue;
3528: }
1.312 djm 3529: if ((c->listening_addr == NULL && addr != NULL) ||
3530: (c->listening_addr != NULL && addr == NULL))
3531: continue;
3532: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3533: debug2("%s: close channel %d", __func__, i);
1.367 djm 3534: channel_free(ssh, c);
1.202 djm 3535: found = 1;
3536: }
3537: }
3538:
1.367 djm 3539: return found;
1.202 djm 3540: }
3541:
1.336 millert 3542: static int
1.367 djm 3543: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3544: {
3545: u_int i;
3546: int found = 0;
3547:
3548: if (path == NULL) {
3549: error("%s: no path specified.", __func__);
3550: return 0;
3551: }
3552:
1.367 djm 3553: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3554: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3555: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3556: continue;
3557: if (c->listening_addr == NULL)
3558: continue;
3559: if (strcmp(c->listening_addr, path) == 0) {
3560: debug2("%s: close channel %d", __func__, i);
1.367 djm 3561: channel_free(ssh, c);
1.336 millert 3562: found = 1;
3563: }
3564: }
3565:
1.367 djm 3566: return found;
1.336 millert 3567: }
3568:
3569: int
1.367 djm 3570: channel_cancel_lport_listener(struct ssh *ssh,
3571: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3572: {
1.367 djm 3573: if (fwd->listen_path != NULL) {
3574: return channel_cancel_lport_listener_streamlocal(ssh,
3575: fwd->listen_path);
3576: } else {
3577: return channel_cancel_lport_listener_tcpip(ssh,
3578: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3579: }
1.336 millert 3580: }
3581:
1.362 markus 3582: /* protocol local port fwd, used by ssh */
1.160 markus 3583: int
1.367 djm 3584: channel_setup_local_fwd_listener(struct ssh *ssh,
3585: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3586: {
1.336 millert 3587: if (fwd->listen_path != NULL) {
1.367 djm 3588: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3589: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3590: } else {
1.367 djm 3591: return channel_setup_fwd_listener_tcpip(ssh,
3592: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3593: }
1.160 markus 3594: }
3595:
3596: /* protocol v2 remote port fwd, used by sshd */
3597: int
1.367 djm 3598: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3599: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3600: {
1.336 millert 3601: if (fwd->listen_path != NULL) {
1.367 djm 3602: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3603: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3604: } else {
1.367 djm 3605: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 3606: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3607: fwd_opts);
3608: }
1.160 markus 3609: }
3610:
1.27 markus 3611: /*
1.312 djm 3612: * Translate the requested rfwd listen host to something usable for
3613: * this server.
3614: */
3615: static const char *
3616: channel_rfwd_bind_host(const char *listen_host)
3617: {
3618: if (listen_host == NULL) {
1.378 ! djm 3619: return "localhost";
1.312 djm 3620: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 ! djm 3621: return "";
1.312 djm 3622: } else
3623: return listen_host;
3624: }
3625:
3626: /*
1.27 markus 3627: * Initiate forwarding of connections to port "port" on remote host through
3628: * the secure channel to host:port from local side.
1.315 markus 3629: * Returns handle (index) for updating the dynamic listen port with
3630: * channel_update_permitted_opens().
1.27 markus 3631: */
1.253 markus 3632: int
1.367 djm 3633: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 3634: {
1.367 djm 3635: int r, success = 0, idx = -1;
3636: char *host_to_connect, *listen_host, *listen_path;
3637: int port_to_connect, listen_port;
1.73 markus 3638:
1.25 markus 3639: /* Send the forward request to the remote side. */
1.358 djm 3640: if (fwd->listen_path != NULL) {
1.367 djm 3641: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3642: (r = sshpkt_put_cstring(ssh,
3643: "streamlocal-forward@openssh.com")) != 0 ||
3644: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3645: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3646: (r = sshpkt_send(ssh)) != 0 ||
3647: (r = ssh_packet_write_wait(ssh)) != 0)
3648: fatal("%s: request streamlocal: %s",
3649: __func__, ssh_err(r));
1.336 millert 3650: } else {
1.367 djm 3651: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3652: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
3653: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3654: (r = sshpkt_put_cstring(ssh,
3655: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
3656: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
3657: (r = sshpkt_send(ssh)) != 0 ||
3658: (r = ssh_packet_write_wait(ssh)) != 0)
3659: fatal("%s: request tcpip-forward: %s",
3660: __func__, ssh_err(r));
1.73 markus 3661: }
1.358 djm 3662: /* Assume that server accepts the request */
3663: success = 1;
1.73 markus 3664: if (success) {
1.305 djm 3665: /* Record that connection to this host/port is permitted. */
1.367 djm 3666: host_to_connect = listen_host = listen_path = NULL;
3667: port_to_connect = listen_port = 0;
1.336 millert 3668: if (fwd->connect_path != NULL) {
1.367 djm 3669: host_to_connect = xstrdup(fwd->connect_path);
3670: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 3671: } else {
1.367 djm 3672: host_to_connect = xstrdup(fwd->connect_host);
3673: port_to_connect = fwd->connect_port;
1.336 millert 3674: }
3675: if (fwd->listen_path != NULL) {
1.367 djm 3676: listen_path = xstrdup(fwd->listen_path);
3677: listen_port = PORT_STREAMLOCAL;
1.336 millert 3678: } else {
1.367 djm 3679: if (fwd->listen_host != NULL)
3680: listen_host = xstrdup(fwd->listen_host);
3681: listen_port = fwd->listen_port;
3682: }
3683: idx = fwd_perm_list_add(ssh, FWDPERM_USER,
3684: host_to_connect, port_to_connect,
3685: listen_host, listen_path, listen_port, NULL);
1.44 markus 3686: }
1.367 djm 3687: return idx;
1.1 deraadt 3688: }
3689:
1.333 markus 3690: static int
3691: open_match(ForwardPermission *allowed_open, const char *requestedhost,
1.336 millert 3692: int requestedport)
1.333 markus 3693: {
3694: if (allowed_open->host_to_connect == NULL)
3695: return 0;
3696: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3697: allowed_open->port_to_connect != requestedport)
3698: return 0;
1.351 dtucker 3699: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3700: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3701: return 0;
3702: return 1;
3703: }
3704:
3705: /*
1.336 millert 3706: * Note that in the listen host/port case
1.333 markus 3707: * we don't support FWD_PERMIT_ANY_PORT and
3708: * need to translate between the configured-host (listen_host)
3709: * and what we've sent to the remote server (channel_rfwd_bind_host)
3710: */
3711: static int
1.336 millert 3712: open_listen_match_tcpip(ForwardPermission *allowed_open,
3713: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3714: {
3715: const char *allowed_host;
3716:
3717: if (allowed_open->host_to_connect == NULL)
3718: return 0;
3719: if (allowed_open->listen_port != requestedport)
3720: return 0;
1.335 djm 3721: if (!translate && allowed_open->listen_host == NULL &&
3722: requestedhost == NULL)
3723: return 1;
1.333 markus 3724: allowed_host = translate ?
3725: channel_rfwd_bind_host(allowed_open->listen_host) :
3726: allowed_open->listen_host;
3727: if (allowed_host == NULL ||
3728: strcmp(allowed_host, requestedhost) != 0)
3729: return 0;
3730: return 1;
3731: }
3732:
1.336 millert 3733: static int
3734: open_listen_match_streamlocal(ForwardPermission *allowed_open,
3735: const char *requestedpath)
3736: {
3737: if (allowed_open->host_to_connect == NULL)
3738: return 0;
3739: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3740: return 0;
3741: if (allowed_open->listen_path == NULL ||
3742: strcmp(allowed_open->listen_path, requestedpath) != 0)
3743: return 0;
3744: return 1;
3745: }
3746:
1.27 markus 3747: /*
1.208 deraadt 3748: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3749: * local side.
3750: */
1.336 millert 3751: static int
1.367 djm 3752: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
3753: const char *host, u_short port)
1.202 djm 3754: {
1.367 djm 3755: struct ssh_channels *sc = ssh->chanctxt;
3756: int r;
3757: u_int i;
3758: ForwardPermission *fp;
1.202 djm 3759:
1.367 djm 3760: for (i = 0; i < sc->num_permitted_opens; i++) {
3761: fp = &sc->permitted_opens[i];
3762: if (open_listen_match_tcpip(fp, host, port, 0))
1.202 djm 3763: break;
1.367 djm 3764: fp = NULL;
1.202 djm 3765: }
1.367 djm 3766: if (fp == NULL) {
1.202 djm 3767: debug("%s: requested forward not found", __func__);
1.312 djm 3768: return -1;
1.202 djm 3769: }
1.367 djm 3770: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3771: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
3772: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3773: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
3774: (r = sshpkt_put_u32(ssh, port)) != 0 ||
3775: (r = sshpkt_send(ssh)) != 0)
3776: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3777:
3778: fwd_perm_clear(fp); /* unregister */
1.336 millert 3779:
3780: return 0;
3781: }
3782:
3783: /*
3784: * Request cancellation of remote forwarding of Unix domain socket
3785: * path from local side.
3786: */
3787: static int
1.367 djm 3788: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3789: {
1.367 djm 3790: struct ssh_channels *sc = ssh->chanctxt;
3791: int r;
3792: u_int i;
3793: ForwardPermission *fp;
1.336 millert 3794:
1.367 djm 3795: for (i = 0; i < sc->num_permitted_opens; i++) {
3796: fp = &sc->permitted_opens[i];
3797: if (open_listen_match_streamlocal(fp, path))
1.336 millert 3798: break;
1.367 djm 3799: fp = NULL;
1.336 millert 3800: }
1.367 djm 3801: if (fp == NULL) {
1.336 millert 3802: debug("%s: requested forward not found", __func__);
3803: return -1;
3804: }
1.367 djm 3805: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3806: (r = sshpkt_put_cstring(ssh,
3807: "cancel-streamlocal-forward@openssh.com")) != 0 ||
3808: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3809: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
3810: (r = sshpkt_send(ssh)) != 0)
3811: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3812:
3813: fwd_perm_clear(fp); /* unregister */
1.312 djm 3814:
3815: return 0;
1.202 djm 3816: }
3817:
3818: /*
1.336 millert 3819: * Request cancellation of remote forwarding of a connection from local side.
3820: */
3821: int
1.367 djm 3822: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3823: {
3824: if (fwd->listen_path != NULL) {
1.367 djm 3825: return channel_request_rforward_cancel_streamlocal(ssh,
3826: fwd->listen_path);
1.336 millert 3827: } else {
1.367 djm 3828: return channel_request_rforward_cancel_tcpip(ssh,
3829: fwd->listen_host,
3830: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 3831: }
1.1 deraadt 3832: }
3833:
1.99 markus 3834: /*
3835: * Permits opening to any host/port if permitted_opens[] is empty. This is
3836: * usually called by the server, because the user could connect to any port
3837: * anyway, and the server has no way to know but to trust the client anyway.
3838: */
3839: void
1.367 djm 3840: channel_permit_all_opens(struct ssh *ssh)
1.99 markus 3841: {
1.367 djm 3842: if (ssh->chanctxt->num_permitted_opens == 0)
3843: ssh->chanctxt->all_opens_permitted = 1;
1.99 markus 3844: }
3845:
1.101 markus 3846: void
1.367 djm 3847: channel_add_permitted_opens(struct ssh *ssh, char *host, int port)
1.99 markus 3848: {
1.367 djm 3849: struct ssh_channels *sc = ssh->chanctxt;
3850:
1.99 markus 3851: debug("allow port forwarding to host %s port %d", host, port);
1.367 djm 3852: fwd_perm_list_add(ssh, FWDPERM_USER, host, port, NULL, NULL, 0, NULL);
3853: sc->all_opens_permitted = 0;
1.315 markus 3854: }
3855:
3856: /*
3857: * Update the listen port for a dynamic remote forward, after
3858: * the actual 'newport' has been allocated. If 'newport' < 0 is
3859: * passed then they entry will be invalidated.
3860: */
3861: void
1.367 djm 3862: channel_update_permitted_opens(struct ssh *ssh, int idx, int newport)
1.315 markus 3863: {
1.367 djm 3864: struct ssh_channels *sc = ssh->chanctxt;
3865:
3866: if (idx < 0 || (u_int)idx >= sc->num_permitted_opens) {
3867: debug("%s: index out of range: %d num_permitted_opens %d",
3868: __func__, idx, sc->num_permitted_opens);
1.315 markus 3869: return;
3870: }
3871: debug("%s allowed port %d for forwarding to host %s port %d",
3872: newport > 0 ? "Updating" : "Removing",
3873: newport,
1.367 djm 3874: sc->permitted_opens[idx].host_to_connect,
3875: sc->permitted_opens[idx].port_to_connect);
3876: if (newport <= 0)
3877: fwd_perm_clear(&sc->permitted_opens[idx]);
3878: else {
3879: sc->permitted_opens[idx].listen_port =
1.315 markus 3880: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
3881: }
1.99 markus 3882: }
3883:
1.258 dtucker 3884: int
1.367 djm 3885: channel_add_adm_permitted_opens(struct ssh *ssh, char *host, int port)
1.257 dtucker 3886: {
1.258 dtucker 3887: debug("config allows port forwarding to host %s port %d", host, port);
1.367 djm 3888: return fwd_perm_list_add(ssh, FWDPERM_ADMIN, host, port,
3889: NULL, NULL, 0, NULL);
1.316 dtucker 3890: }
3891:
3892: void
1.367 djm 3893: channel_disable_adm_local_opens(struct ssh *ssh)
1.99 markus 3894: {
1.367 djm 3895: channel_clear_adm_permitted_opens(ssh);
3896: fwd_perm_list_add(ssh, FWDPERM_ADMIN, NULL, 0, NULL, NULL, 0, NULL);
1.257 dtucker 3897: }
3898:
3899: void
1.367 djm 3900: channel_clear_permitted_opens(struct ssh *ssh)
1.257 dtucker 3901: {
1.367 djm 3902: struct ssh_channels *sc = ssh->chanctxt;
1.99 markus 3903:
1.367 djm 3904: sc->permitted_opens = xrecallocarray(sc->permitted_opens,
3905: sc->num_permitted_opens, 0, sizeof(*sc->permitted_opens));
3906: sc->num_permitted_opens = 0;
1.278 dtucker 3907: }
3908:
3909: void
1.367 djm 3910: channel_clear_adm_permitted_opens(struct ssh *ssh)
1.278 dtucker 3911: {
1.367 djm 3912: struct ssh_channels *sc = ssh->chanctxt;
1.278 dtucker 3913:
1.367 djm 3914: sc->permitted_adm_opens = xrecallocarray(sc->permitted_adm_opens,
3915: sc->num_adm_permitted_opens, 0, sizeof(*sc->permitted_adm_opens));
3916: sc->num_adm_permitted_opens = 0;
1.99 markus 3917: }
3918:
1.314 dtucker 3919: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3920: int
3921: permitopen_port(const char *p)
3922: {
3923: int port;
3924:
3925: if (strcmp(p, "*") == 0)
3926: return FWD_PERMIT_ANY_PORT;
3927: if ((port = a2port(p)) > 0)
3928: return port;
3929: return -1;
3930: }
3931:
1.276 djm 3932: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 3933: static int
1.276 djm 3934: connect_next(struct channel_connect *cctx)
1.41 markus 3935: {
1.276 djm 3936: int sock, saved_errno;
1.336 millert 3937: struct sockaddr_un *sunaddr;
1.367 djm 3938: char ntop[NI_MAXHOST];
3939: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 3940:
1.276 djm 3941: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 3942: switch (cctx->ai->ai_family) {
3943: case AF_UNIX:
3944: /* unix:pathname instead of host:port */
3945: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
3946: strlcpy(ntop, "unix", sizeof(ntop));
3947: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
3948: break;
3949: case AF_INET:
3950: case AF_INET6:
3951: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
3952: ntop, sizeof(ntop), strport, sizeof(strport),
3953: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
3954: error("connect_next: getnameinfo failed");
3955: continue;
3956: }
3957: break;
3958: default:
1.41 markus 3959: continue;
3960: }
1.300 dtucker 3961: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
3962: cctx->ai->ai_protocol)) == -1) {
1.276 djm 3963: if (cctx->ai->ai_next == NULL)
1.186 djm 3964: error("socket: %.100s", strerror(errno));
3965: else
3966: verbose("socket: %.100s", strerror(errno));
1.41 markus 3967: continue;
3968: }
1.205 djm 3969: if (set_nonblock(sock) == -1)
3970: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 3971: if (connect(sock, cctx->ai->ai_addr,
3972: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
3973: debug("connect_next: host %.100s ([%.100s]:%s): "
3974: "%.100s", cctx->host, ntop, strport,
1.41 markus 3975: strerror(errno));
1.276 djm 3976: saved_errno = errno;
1.41 markus 3977: close(sock);
1.276 djm 3978: errno = saved_errno;
1.89 stevesk 3979: continue; /* fail -- try next */
1.41 markus 3980: }
1.336 millert 3981: if (cctx->ai->ai_family != AF_UNIX)
3982: set_nodelay(sock);
1.276 djm 3983: debug("connect_next: host %.100s ([%.100s]:%s) "
3984: "in progress, fd=%d", cctx->host, ntop, strport, sock);
3985: cctx->ai = cctx->ai->ai_next;
3986: return sock;
3987: }
3988: return -1;
3989: }
1.41 markus 3990:
1.276 djm 3991: static void
3992: channel_connect_ctx_free(struct channel_connect *cctx)
3993: {
1.321 djm 3994: free(cctx->host);
1.336 millert 3995: if (cctx->aitop) {
3996: if (cctx->aitop->ai_family == AF_UNIX)
3997: free(cctx->aitop);
3998: else
3999: freeaddrinfo(cctx->aitop);
4000: }
1.329 tedu 4001: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4002: }
4003:
1.357 dtucker 4004: /*
1.372 markus 4005: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4006: * passing back the failure reason if appropriate.
4007: */
1.372 markus 4008: static int
4009: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4010: char *ctype, char *rname, struct channel_connect *cctx,
4011: int *reason, const char **errmsg)
1.276 djm 4012: {
4013: struct addrinfo hints;
4014: int gaierr;
4015: int sock = -1;
4016: char strport[NI_MAXSERV];
1.336 millert 4017:
4018: if (port == PORT_STREAMLOCAL) {
4019: struct sockaddr_un *sunaddr;
4020: struct addrinfo *ai;
4021:
4022: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4023: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4024: return -1;
1.336 millert 4025: }
4026:
4027: /*
4028: * Fake up a struct addrinfo for AF_UNIX connections.
4029: * channel_connect_ctx_free() must check ai_family
4030: * and use free() not freeaddirinfo() for AF_UNIX.
4031: */
4032: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4033: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4034: ai->ai_addr = (struct sockaddr *)(ai + 1);
4035: ai->ai_addrlen = sizeof(*sunaddr);
4036: ai->ai_family = AF_UNIX;
1.372 markus 4037: ai->ai_socktype = socktype;
1.336 millert 4038: ai->ai_protocol = PF_UNSPEC;
4039: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4040: sunaddr->sun_family = AF_UNIX;
4041: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4042: cctx->aitop = ai;
1.336 millert 4043: } else {
4044: memset(&hints, 0, sizeof(hints));
1.367 djm 4045: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4046: hints.ai_socktype = socktype;
1.336 millert 4047: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4048: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4049: != 0) {
4050: if (errmsg != NULL)
4051: *errmsg = ssh_gai_strerror(gaierr);
4052: if (reason != NULL)
4053: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4054: error("connect_to %.100s: unknown host (%s)", name,
4055: ssh_gai_strerror(gaierr));
1.372 markus 4056: return -1;
1.336 millert 4057: }
1.41 markus 4058: }
1.276 djm 4059:
1.372 markus 4060: cctx->host = xstrdup(name);
4061: cctx->port = port;
4062: cctx->ai = cctx->aitop;
1.276 djm 4063:
1.372 markus 4064: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4065: error("connect to %.100s port %d failed: %s",
1.336 millert 4066: name, port, strerror(errno));
1.372 markus 4067: return -1;
4068: }
4069:
4070: return sock;
4071: }
4072:
4073: /* Return CONNECTING channel to remote host:port or local socket path */
4074: static Channel *
4075: connect_to(struct ssh *ssh, const char *host, int port,
4076: char *ctype, char *rname)
4077: {
4078: struct channel_connect cctx;
4079: Channel *c;
4080: int sock;
4081:
4082: memset(&cctx, 0, sizeof(cctx));
4083: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4084: &cctx, NULL, NULL);
4085: if (sock == -1) {
1.276 djm 4086: channel_connect_ctx_free(&cctx);
4087: return NULL;
1.41 markus 4088: }
1.367 djm 4089: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4090: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4091: c->host_port = port;
4092: c->path = xstrdup(host);
1.276 djm 4093: c->connect_ctx = cctx;
1.372 markus 4094:
1.276 djm 4095: return c;
1.41 markus 4096: }
1.99 markus 4097:
1.354 markus 4098: /*
4099: * returns either the newly connected channel or the downstream channel
4100: * that needs to deal with this connection.
4101: */
1.276 djm 4102: Channel *
1.367 djm 4103: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4104: u_short listen_port, char *ctype, char *rname)
1.73 markus 4105: {
1.367 djm 4106: struct ssh_channels *sc = ssh->chanctxt;
4107: u_int i;
4108: ForwardPermission *fp;
1.99 markus 4109:
1.367 djm 4110: for (i = 0; i < sc->num_permitted_opens; i++) {
4111: fp = &sc->permitted_opens[i];
4112: if (open_listen_match_tcpip(fp, listen_host, listen_port, 1)) {
4113: if (fp->downstream)
4114: return fp->downstream;
1.372 markus 4115: if (fp->port_to_connect == 0)
4116: return rdynamic_connect_prepare(ssh,
4117: ctype, rname);
1.367 djm 4118: return connect_to(ssh,
4119: fp->host_to_connect, fp->port_to_connect,
4120: ctype, rname);
1.276 djm 4121: }
4122: }
1.74 markus 4123: error("WARNING: Server requests forwarding for unknown listen_port %d",
4124: listen_port);
1.276 djm 4125: return NULL;
1.73 markus 4126: }
4127:
1.336 millert 4128: Channel *
1.367 djm 4129: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4130: char *ctype, char *rname)
1.336 millert 4131: {
1.367 djm 4132: struct ssh_channels *sc = ssh->chanctxt;
4133: u_int i;
4134: ForwardPermission *fp;
1.336 millert 4135:
1.367 djm 4136: for (i = 0; i < sc->num_permitted_opens; i++) {
4137: fp = &sc->permitted_opens[i];
4138: if (open_listen_match_streamlocal(fp, path)) {
4139: return connect_to(ssh,
4140: fp->host_to_connect, fp->port_to_connect,
4141: ctype, rname);
1.336 millert 4142: }
4143: }
4144: error("WARNING: Server requests forwarding for unknown path %.100s",
4145: path);
4146: return NULL;
4147: }
4148:
1.99 markus 4149: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4150: Channel *
1.367 djm 4151: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4152: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4153: {
1.367 djm 4154: struct ssh_channels *sc = ssh->chanctxt;
1.372 markus 4155: struct channel_connect cctx;
4156: Channel *c;
1.367 djm 4157: u_int i, permit, permit_adm = 1;
1.372 markus 4158: int sock;
1.367 djm 4159: ForwardPermission *fp;
1.99 markus 4160:
1.367 djm 4161: permit = sc->all_opens_permitted;
1.99 markus 4162: if (!permit) {
1.367 djm 4163: for (i = 0; i < sc->num_permitted_opens; i++) {
4164: fp = &sc->permitted_opens[i];
4165: if (open_match(fp, host, port)) {
1.99 markus 4166: permit = 1;
1.333 markus 4167: break;
4168: }
1.367 djm 4169: }
1.257 dtucker 4170: }
1.99 markus 4171:
1.367 djm 4172: if (sc->num_adm_permitted_opens > 0) {
1.257 dtucker 4173: permit_adm = 0;
1.367 djm 4174: for (i = 0; i < sc->num_adm_permitted_opens; i++) {
4175: fp = &sc->permitted_adm_opens[i];
4176: if (open_match(fp, host, port)) {
1.257 dtucker 4177: permit_adm = 1;
1.333 markus 4178: break;
4179: }
1.367 djm 4180: }
1.99 markus 4181: }
1.257 dtucker 4182:
4183: if (!permit || !permit_adm) {
1.188 itojun 4184: logit("Received request to connect to host %.100s port %d, "
1.99 markus 4185: "but the request was denied.", host, port);
1.357 dtucker 4186: if (reason != NULL)
4187: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4188: return NULL;
1.99 markus 4189: }
1.372 markus 4190:
4191: memset(&cctx, 0, sizeof(cctx));
4192: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4193: &cctx, reason, errmsg);
4194: if (sock == -1) {
4195: channel_connect_ctx_free(&cctx);
4196: return NULL;
4197: }
4198:
4199: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4200: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4201: c->host_port = port;
4202: c->path = xstrdup(host);
4203: c->connect_ctx = cctx;
4204:
4205: return c;
1.336 millert 4206: }
4207:
4208: /* Check if connecting to that path is permitted and connect. */
4209: Channel *
1.367 djm 4210: channel_connect_to_path(struct ssh *ssh, const char *path,
4211: char *ctype, char *rname)
1.336 millert 4212: {
1.367 djm 4213: struct ssh_channels *sc = ssh->chanctxt;
4214: u_int i, permit, permit_adm = 1;
4215: ForwardPermission *fp;
1.336 millert 4216:
1.367 djm 4217: permit = sc->all_opens_permitted;
1.336 millert 4218: if (!permit) {
1.367 djm 4219: for (i = 0; i < sc->num_permitted_opens; i++) {
4220: fp = &sc->permitted_opens[i];
4221: if (open_match(fp, path, PORT_STREAMLOCAL)) {
1.336 millert 4222: permit = 1;
4223: break;
4224: }
1.367 djm 4225: }
1.336 millert 4226: }
4227:
1.367 djm 4228: if (sc->num_adm_permitted_opens > 0) {
1.336 millert 4229: permit_adm = 0;
1.367 djm 4230: for (i = 0; i < sc->num_adm_permitted_opens; i++) {
4231: fp = &sc->permitted_adm_opens[i];
4232: if (open_match(fp, path, PORT_STREAMLOCAL)) {
1.336 millert 4233: permit_adm = 1;
4234: break;
4235: }
1.367 djm 4236: }
1.336 millert 4237: }
4238:
4239: if (!permit || !permit_adm) {
4240: logit("Received request to connect to path %.100s, "
4241: "but the request was denied.", path);
4242: return NULL;
4243: }
1.367 djm 4244: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4245: }
4246:
4247: void
1.367 djm 4248: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4249: {
1.367 djm 4250: struct ssh_channels *sc = ssh->chanctxt;
4251: struct winsize ws;
4252: int r;
1.209 avsm 4253: u_int i;
1.204 djm 4254:
1.367 djm 4255: for (i = 0; i < sc->channels_alloc; i++) {
4256: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4257: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4258: continue;
1.367 djm 4259: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
1.204 djm 4260: continue;
1.367 djm 4261: channel_request_start(ssh, i, "window-change", 0);
4262: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4263: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4264: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4265: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4266: (r = sshpkt_send(ssh)) != 0)
4267: fatal("%s: channel %u: send window-change: %s",
4268: __func__, i, ssh_err(r));
1.204 djm 4269: }
1.372 markus 4270: }
4271:
4272: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4273: static Channel *
4274: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4275: {
4276: Channel *c;
4277: int r;
4278:
4279: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4280: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4281: c->host_port = 0;
4282: c->path = NULL;
4283:
4284: /*
4285: * We need to open the channel before we have a FD,
4286: * so that we can get SOCKS header from peer.
4287: */
4288: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4289: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4290: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4291: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
4292: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
4293: fatal("%s: channel %i: confirm: %s", __func__,
4294: c->self, ssh_err(r));
4295: }
4296: return c;
4297: }
4298:
4299: /* Return CONNECTING socket to remote host:port or local socket path */
4300: static int
4301: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4302: {
4303: struct channel_connect cctx;
4304: int sock;
4305:
4306: memset(&cctx, 0, sizeof(cctx));
4307: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4308: NULL, &cctx, NULL, NULL);
4309: if (sock == -1)
4310: channel_connect_ctx_free(&cctx);
4311: else {
4312: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4313: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4314: c->connect_ctx = cctx;
4315: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4316: }
4317: return sock;
1.99 markus 4318: }
4319:
1.121 markus 4320: /* -- X11 forwarding */
1.1 deraadt 4321:
1.27 markus 4322: /*
4323: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4324: * Returns 0 and a suitable display number for the DISPLAY variable
4325: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4326: */
1.141 stevesk 4327: int
1.367 djm 4328: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4329: int x11_use_localhost, int single_connection,
4330: u_int *display_numberp, int **chanids)
1.1 deraadt 4331: {
1.149 markus 4332: Channel *nc = NULL;
1.31 markus 4333: int display_number, sock;
4334: u_short port;
1.35 markus 4335: struct addrinfo hints, *ai, *aitop;
4336: char strport[NI_MAXSERV];
4337: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4338:
1.224 markus 4339: if (chanids == NULL)
4340: return -1;
4341:
1.33 markus 4342: for (display_number = x11_display_offset;
1.148 deraadt 4343: display_number < MAX_DISPLAYS;
4344: display_number++) {
1.25 markus 4345: port = 6000 + display_number;
1.35 markus 4346: memset(&hints, 0, sizeof(hints));
1.367 djm 4347: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4348: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4349: hints.ai_socktype = SOCK_STREAM;
4350: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4351: if ((gaierr = getaddrinfo(NULL, strport,
4352: &hints, &aitop)) != 0) {
1.271 dtucker 4353: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4354: return -1;
1.25 markus 4355: }
1.35 markus 4356: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4357: if (ai->ai_family != AF_INET &&
4358: ai->ai_family != AF_INET6)
1.35 markus 4359: continue;
1.300 dtucker 4360: sock = socket(ai->ai_family, ai->ai_socktype,
4361: ai->ai_protocol);
1.35 markus 4362: if (sock < 0) {
4363: error("socket: %.100s", strerror(errno));
1.203 markus 4364: freeaddrinfo(aitop);
1.141 stevesk 4365: return -1;
1.35 markus 4366: }
1.376 djm 4367: set_reuseaddr(sock);
1.35 markus 4368: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.367 djm 4369: debug2("%s: bind port %d: %.100s", __func__,
4370: port, strerror(errno));
1.35 markus 4371: close(sock);
1.367 djm 4372: for (n = 0; n < num_socks; n++)
1.35 markus 4373: close(socks[n]);
4374: num_socks = 0;
4375: break;
4376: }
4377: socks[num_socks++] = sock;
4378: if (num_socks == NUM_SOCKS)
4379: break;
1.25 markus 4380: }
1.83 stevesk 4381: freeaddrinfo(aitop);
1.35 markus 4382: if (num_socks > 0)
4383: break;
1.25 markus 4384: }
4385: if (display_number >= MAX_DISPLAYS) {
4386: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4387: return -1;
1.25 markus 4388: }
4389: /* Start listening for connections on the socket. */
1.35 markus 4390: for (n = 0; n < num_socks; n++) {
4391: sock = socks[n];
1.199 markus 4392: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 4393: error("listen: %.100s", strerror(errno));
4394: close(sock);
1.141 stevesk 4395: return -1;
1.35 markus 4396: }
1.25 markus 4397: }
1.35 markus 4398:
4399: /* Allocate a channel for each socket. */
1.242 djm 4400: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4401: for (n = 0; n < num_socks; n++) {
4402: sock = socks[n];
1.367 djm 4403: nc = channel_new(ssh, "x11 listener",
1.51 markus 4404: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4405: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4406: 0, "X11 inet listener", 1);
1.167 markus 4407: nc->single_connection = single_connection;
1.224 markus 4408: (*chanids)[n] = nc->self;
1.35 markus 4409: }
1.224 markus 4410: (*chanids)[n] = -1;
1.1 deraadt 4411:
1.141 stevesk 4412: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4413: *display_numberp = display_number;
1.367 djm 4414: return 0;
1.1 deraadt 4415: }
4416:
1.127 itojun 4417: static int
1.77 markus 4418: connect_local_xsocket(u_int dnr)
1.1 deraadt 4419: {
1.25 markus 4420: int sock;
4421: struct sockaddr_un addr;
4422:
1.147 stevesk 4423: sock = socket(AF_UNIX, SOCK_STREAM, 0);
4424: if (sock < 0)
4425: error("socket: %.100s", strerror(errno));
4426: memset(&addr, 0, sizeof(addr));
4427: addr.sun_family = AF_UNIX;
4428: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4429: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4430: return sock;
4431: close(sock);
1.25 markus 4432: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4433: return -1;
1.1 deraadt 4434: }
4435:
1.51 markus 4436: int
1.367 djm 4437: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4438: {
1.248 deraadt 4439: u_int display_number;
1.25 markus 4440: const char *display;
1.51 markus 4441: char buf[1024], *cp;
1.35 markus 4442: struct addrinfo hints, *ai, *aitop;
4443: char strport[NI_MAXSERV];
1.248 deraadt 4444: int gaierr, sock = 0;
1.25 markus 4445:
4446: /* Try to open a socket for the local X server. */
4447: display = getenv("DISPLAY");
4448: if (!display) {
4449: error("DISPLAY not set.");
1.51 markus 4450: return -1;
1.25 markus 4451: }
1.27 markus 4452: /*
4453: * Now we decode the value of the DISPLAY variable and make a
4454: * connection to the real X server.
4455: */
4456:
4457: /*
4458: * Check if it is a unix domain socket. Unix domain displays are in
4459: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4460: */
1.25 markus 4461: if (strncmp(display, "unix:", 5) == 0 ||
4462: display[0] == ':') {
4463: /* Connect to the unix domain socket. */
1.367 djm 4464: if (sscanf(strrchr(display, ':') + 1, "%u",
4465: &display_number) != 1) {
4466: error("Could not parse display number from DISPLAY: "
4467: "%.100s", display);
1.51 markus 4468: return -1;
1.25 markus 4469: }
4470: /* Create a socket. */
4471: sock = connect_local_xsocket(display_number);
4472: if (sock < 0)
1.51 markus 4473: return -1;
1.25 markus 4474:
4475: /* OK, we now have a connection to the display. */
1.51 markus 4476: return sock;
1.25 markus 4477: }
1.27 markus 4478: /*
4479: * Connect to an inet socket. The DISPLAY value is supposedly
4480: * hostname:d[.s], where hostname may also be numeric IP address.
4481: */
1.145 stevesk 4482: strlcpy(buf, display, sizeof(buf));
1.25 markus 4483: cp = strchr(buf, ':');
4484: if (!cp) {
4485: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4486: return -1;
1.25 markus 4487: }
4488: *cp = 0;
1.367 djm 4489: /*
4490: * buf now contains the host name. But first we parse the
4491: * display number.
4492: */
1.248 deraadt 4493: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4494: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4495: display);
1.51 markus 4496: return -1;
1.25 markus 4497: }
1.35 markus 4498:
4499: /* Look up the host address */
4500: memset(&hints, 0, sizeof(hints));
1.367 djm 4501: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4502: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4503: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4504: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4505: error("%.100s: unknown host. (%s)", buf,
4506: ssh_gai_strerror(gaierr));
1.51 markus 4507: return -1;
1.25 markus 4508: }
1.35 markus 4509: for (ai = aitop; ai; ai = ai->ai_next) {
4510: /* Create a socket. */
1.300 dtucker 4511: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 4512: if (sock < 0) {
1.194 markus 4513: debug2("socket: %.100s", strerror(errno));
1.41 markus 4514: continue;
4515: }
4516: /* Connect it to the display. */
4517: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 4518: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4519: 6000 + display_number, strerror(errno));
4520: close(sock);
4521: continue;
4522: }
4523: /* Success */
4524: break;
1.35 markus 4525: }
4526: freeaddrinfo(aitop);
4527: if (!ai) {
1.367 djm 4528: error("connect %.100s port %u: %.100s", buf,
4529: 6000 + display_number, strerror(errno));
1.51 markus 4530: return -1;
1.25 markus 4531: }
1.162 stevesk 4532: set_nodelay(sock);
1.51 markus 4533: return sock;
4534: }
4535:
4536: /*
1.27 markus 4537: * Requests forwarding of X11 connections, generates fake authentication
4538: * data, and enables authentication spoofing.
1.121 markus 4539: * This should be called in the client only.
1.27 markus 4540: */
1.49 markus 4541: void
1.367 djm 4542: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4543: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4544: {
1.367 djm 4545: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4546: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4547: u_int i, value;
1.367 djm 4548: const char *cp;
1.25 markus 4549: char *new_data;
1.367 djm 4550: int r, screen_number;
1.25 markus 4551:
1.367 djm 4552: if (sc->x11_saved_display == NULL)
4553: sc->x11_saved_display = xstrdup(disp);
4554: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4555: error("x11_request_forwarding_with_spoofing: different "
4556: "$DISPLAY already forwarded");
4557: return;
4558: }
4559:
1.266 djm 4560: cp = strchr(disp, ':');
1.25 markus 4561: if (cp)
4562: cp = strchr(cp, '.');
4563: if (cp)
1.245 deraadt 4564: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4565: else
4566: screen_number = 0;
4567:
1.367 djm 4568: if (sc->x11_saved_proto == NULL) {
1.219 djm 4569: /* Save protocol name. */
1.367 djm 4570: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4571:
4572: /* Extract real authentication data. */
1.367 djm 4573: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4574: for (i = 0; i < data_len; i++) {
4575: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4576: fatal("x11_request_forwarding: bad "
4577: "authentication data: %.100s", data);
1.367 djm 4578: sc->x11_saved_data[i] = value;
1.219 djm 4579: }
1.367 djm 4580: sc->x11_saved_data_len = data_len;
1.353 natano 4581:
4582: /* Generate fake data of the same length. */
1.367 djm 4583: sc->x11_fake_data = xmalloc(data_len);
4584: arc4random_buf(sc->x11_fake_data, data_len);
4585: sc->x11_fake_data_len = data_len;
1.25 markus 4586: }
4587:
4588: /* Convert the fake data into hex. */
1.367 djm 4589: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 4590:
4591: /* Send the request packet. */
1.367 djm 4592: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4593: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4594: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4595: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4596: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4597: (r = sshpkt_send(ssh)) != 0 ||
4598: (r = ssh_packet_write_wait(ssh)) != 0)
4599: fatal("%s: send x11-req: %s", __func__, ssh_err(r));
1.321 djm 4600: free(new_data);
1.1 deraadt 4601: }