Annotation of src/usr.bin/ssh/channels.c, Revision 1.372
1.372 ! markus 1: /* $OpenBSD: channels.c,v 1.371 2017/09/19 12:10:30 millert Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.336 millert 43: #include <sys/stat.h>
1.234 stevesk 44: #include <sys/ioctl.h>
1.235 stevesk 45: #include <sys/un.h>
1.251 stevesk 46: #include <sys/socket.h>
1.261 stevesk 47: #include <sys/time.h>
1.275 djm 48: #include <sys/queue.h>
1.251 stevesk 49:
50: #include <netinet/in.h>
51: #include <arpa/inet.h>
1.233 stevesk 52:
1.254 stevesk 53: #include <errno.h>
1.298 dtucker 54: #include <fcntl.h>
1.367 djm 55: #include <limits.h>
1.255 stevesk 56: #include <netdb.h>
1.367 djm 57: #include <stdarg.h>
1.341 millert 58: #include <stdint.h>
1.263 stevesk 59: #include <stdio.h>
1.262 stevesk 60: #include <stdlib.h>
1.260 stevesk 61: #include <string.h>
1.233 stevesk 62: #include <termios.h>
1.256 stevesk 63: #include <unistd.h>
1.1 deraadt 64:
1.265 deraadt 65: #include "xmalloc.h"
1.1 deraadt 66: #include "ssh.h"
1.82 markus 67: #include "ssh2.h"
1.354 markus 68: #include "ssherr.h"
1.367 djm 69: #include "sshbuf.h"
1.1 deraadt 70: #include "packet.h"
1.82 markus 71: #include "log.h"
72: #include "misc.h"
1.14 markus 73: #include "channels.h"
74: #include "compat.h"
1.82 markus 75: #include "canohost.h"
1.64 markus 76: #include "key.h"
77: #include "authfd.h"
1.147 stevesk 78: #include "pathnames.h"
1.1 deraadt 79:
1.367 djm 80: /* -- agent forwarding */
81: #define NUM_SOCKS 10
1.12 markus 82:
1.367 djm 83: /* -- tcp forwarding */
84: /* special-case port number meaning allow any port */
85: #define FWD_PERMIT_ANY_PORT 0
1.1 deraadt 86:
1.367 djm 87: /* special-case wildcard meaning allow any host */
88: #define FWD_PERMIT_ANY_HOST "*"
1.1 deraadt 89:
1.367 djm 90: /* -- X11 forwarding */
91: /* Maximum number of fake X11 displays to try. */
92: #define MAX_DISPLAYS 1000
1.1 deraadt 93:
1.27 markus 94: /*
95: * Data structure for storing which hosts are permitted for forward requests.
96: * The local sides of any remote forwards are stored in this array to prevent
97: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
98: * network (which might be behind a firewall).
99: */
1.336 millert 100: /* XXX: streamlocal wants a path instead of host:port */
101: /* Overload host_to_connect; we could just make this match Forward */
102: /* XXX - can we use listen_host instead of listen_path? */
1.25 markus 103: typedef struct {
1.41 markus 104: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 105: int port_to_connect; /* Connect to 'port'. */
1.333 markus 106: char *listen_host; /* Remote side should listen address. */
1.336 millert 107: char *listen_path; /* Remote side should listen path. */
108: int listen_port; /* Remote side should listen port. */
1.354 markus 109: Channel *downstream; /* Downstream mux*/
1.1 deraadt 110: } ForwardPermission;
111:
1.367 djm 112: typedef void chan_fn(struct ssh *, Channel *c,
113: fd_set *readset, fd_set *writeset);
1.121 markus 114:
1.367 djm 115: /* Master structure for channels state */
116: struct ssh_channels {
117: /*
118: * Pointer to an array containing all allocated channels. The array
119: * is dynamically extended as needed.
120: */
121: Channel **channels;
1.257 dtucker 122:
1.367 djm 123: /*
124: * Size of the channel array. All slots of the array must always be
125: * initialized (at least the type field); unused slots set to NULL
126: */
127: u_int channels_alloc;
1.257 dtucker 128:
1.367 djm 129: /*
130: * Maximum file descriptor value used in any of the channels. This is
131: * updated in channel_new.
132: */
133: int channel_max_fd;
1.257 dtucker 134:
1.367 djm 135: /*
136: * 'channel_pre*' are called just before select() to add any bits
137: * relevant to channels in the select bitmasks.
138: *
139: * 'channel_post*': perform any appropriate operations for
140: * channels which have events pending.
141: */
142: chan_fn **channel_pre;
143: chan_fn **channel_post;
1.314 dtucker 144:
1.367 djm 145: /* -- tcp forwarding */
1.351 dtucker 146:
1.367 djm 147: /* List of all permitted host/port pairs to connect by the user. */
148: ForwardPermission *permitted_opens;
1.1 deraadt 149:
1.367 djm 150: /* List of all permitted host/port pairs to connect by the admin. */
151: ForwardPermission *permitted_adm_opens;
1.121 markus 152:
1.367 djm 153: /*
154: * Number of permitted host/port pairs in the array permitted by
155: * the user.
156: */
157: u_int num_permitted_opens;
1.121 markus 158:
1.367 djm 159: /*
160: * Number of permitted host/port pair in the array permitted by
161: * the admin.
162: */
163: u_int num_adm_permitted_opens;
1.121 markus 164:
1.367 djm 165: /*
166: * If this is true, all opens are permitted. This is the case on
167: * the server on which we have to trust the client anyway, and the
168: * user could do anything after logging in anyway.
169: */
170: int all_opens_permitted;
1.219 djm 171:
1.367 djm 172: /* -- X11 forwarding */
1.121 markus 173:
1.367 djm 174: /* Saved X11 local (client) display. */
175: char *x11_saved_display;
1.121 markus 176:
1.367 djm 177: /* Saved X11 authentication protocol name. */
178: char *x11_saved_proto;
1.347 djm 179:
1.367 djm 180: /* Saved X11 authentication data. This is the real data. */
181: char *x11_saved_data;
182: u_int x11_saved_data_len;
1.121 markus 183:
1.367 djm 184: /* Deadline after which all X11 connections are refused */
185: u_int x11_refuse_time;
1.121 markus 186:
1.367 djm 187: /*
188: * Fake X11 authentication data. This is what the server will be
189: * sending us; we should replace any occurrences of this by the
190: * real data.
191: */
192: u_char *x11_fake_data;
193: u_int x11_fake_data_len;
1.121 markus 194:
1.367 djm 195: /* AF_UNSPEC or AF_INET or AF_INET6 */
196: int IPv4or6;
197: };
1.1 deraadt 198:
1.121 markus 199: /* helper */
1.367 djm 200: static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
1.354 markus 201: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 202:
1.276 djm 203: /* non-blocking connect helpers */
204: static int connect_next(struct channel_connect *);
205: static void channel_connect_ctx_free(struct channel_connect *);
1.372 ! markus 206: static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
! 207: static int rdynamic_connect_finish(struct ssh *, Channel *);
1.276 djm 208:
1.367 djm 209: /* Setup helper */
210: static void channel_handler_init(struct ssh_channels *sc);
211:
1.121 markus 212: /* -- channel core */
1.41 markus 213:
1.367 djm 214: void
215: channel_init_channels(struct ssh *ssh)
216: {
217: struct ssh_channels *sc;
218:
219: if ((sc = calloc(1, sizeof(*sc))) == NULL ||
220: (sc->channel_pre = calloc(SSH_CHANNEL_MAX_TYPE,
221: sizeof(*sc->channel_pre))) == NULL ||
222: (sc->channel_post = calloc(SSH_CHANNEL_MAX_TYPE,
223: sizeof(*sc->channel_post))) == NULL)
224: fatal("%s: allocation failed", __func__);
225: sc->channels_alloc = 10;
226: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
227: sc->IPv4or6 = AF_UNSPEC;
228: channel_handler_init(sc);
229:
230: ssh->chanctxt = sc;
231: }
232:
1.41 markus 233: Channel *
1.367 djm 234: channel_by_id(struct ssh *ssh, int id)
1.41 markus 235: {
236: Channel *c;
1.113 markus 237:
1.367 djm 238: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
239: logit("%s: %d: bad id", __func__, id);
1.41 markus 240: return NULL;
241: }
1.367 djm 242: c = ssh->chanctxt->channels[id];
1.113 markus 243: if (c == NULL) {
1.367 djm 244: logit("%s: %d: bad id: channel free", __func__, id);
1.41 markus 245: return NULL;
246: }
247: return c;
1.55 markus 248: }
249:
1.354 markus 250: Channel *
1.368 djm 251: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 252: {
253: Channel *c;
254: u_int i;
255:
1.367 djm 256: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
257: c = ssh->chanctxt->channels[i];
1.368 djm 258: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 259: return c;
260: }
261: return NULL;
262: }
263:
1.27 markus 264: /*
1.229 markus 265: * Returns the channel if it is allowed to receive protocol messages.
266: * Private channels, like listening sockets, may not receive messages.
267: */
268: Channel *
1.367 djm 269: channel_lookup(struct ssh *ssh, int id)
1.229 markus 270: {
271: Channel *c;
272:
1.367 djm 273: if ((c = channel_by_id(ssh, id)) == NULL)
274: return NULL;
1.229 markus 275:
1.237 deraadt 276: switch (c->type) {
1.229 markus 277: case SSH_CHANNEL_X11_OPEN:
278: case SSH_CHANNEL_LARVAL:
279: case SSH_CHANNEL_CONNECTING:
280: case SSH_CHANNEL_DYNAMIC:
1.372 ! markus 281: case SSH_CHANNEL_RDYNAMIC_OPEN:
! 282: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 283: case SSH_CHANNEL_OPENING:
284: case SSH_CHANNEL_OPEN:
1.323 dtucker 285: case SSH_CHANNEL_ABANDONED:
1.354 markus 286: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 287: return c;
1.229 markus 288: }
289: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 290: return NULL;
1.229 markus 291: }
292:
293: /*
1.55 markus 294: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 295: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 296: */
1.127 itojun 297: static void
1.367 djm 298: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 299: int extusage, int nonblock, int is_tty)
1.1 deraadt 300: {
1.367 djm 301: struct ssh_channels *sc = ssh->chanctxt;
302:
1.25 markus 303: /* Update the maximum file descriptor value. */
1.367 djm 304: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, rfd);
305: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, wfd);
306: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, efd);
1.84 markus 307:
1.298 dtucker 308: if (rfd != -1)
309: fcntl(rfd, F_SETFD, FD_CLOEXEC);
310: if (wfd != -1 && wfd != rfd)
311: fcntl(wfd, F_SETFD, FD_CLOEXEC);
312: if (efd != -1 && efd != rfd && efd != wfd)
313: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 314:
1.52 markus 315: c->rfd = rfd;
316: c->wfd = wfd;
317: c->sock = (rfd == wfd) ? rfd : -1;
318: c->efd = efd;
319: c->extended_usage = extusage;
1.71 markus 320:
1.282 dtucker 321: if ((c->isatty = is_tty) != 0)
1.194 markus 322: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 323:
1.71 markus 324: /* enable nonblocking mode */
325: if (nonblock) {
326: if (rfd != -1)
327: set_nonblock(rfd);
328: if (wfd != -1)
329: set_nonblock(wfd);
330: if (efd != -1)
331: set_nonblock(efd);
332: }
1.52 markus 333: }
334:
335: /*
336: * Allocate a new channel object and set its type and socket. This will cause
337: * remote_name to be freed.
338: */
1.113 markus 339: Channel *
1.367 djm 340: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 341: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 342: {
1.367 djm 343: struct ssh_channels *sc = ssh->chanctxt;
344: u_int i, found;
1.52 markus 345: Channel *c;
1.25 markus 346:
347: /* Try to find a free slot where to put the new channel. */
1.367 djm 348: for (i = 0; i < sc->channels_alloc; i++) {
349: if (sc->channels[i] == NULL) {
1.25 markus 350: /* Found a free slot. */
1.367 djm 351: found = i;
1.25 markus 352: break;
353: }
1.367 djm 354: }
355: if (i >= sc->channels_alloc) {
356: /*
357: * There are no free slots. Take last+1 slot and expand
358: * the array.
359: */
360: found = sc->channels_alloc;
361: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
362: fatal("%s: internal error: channels_alloc %d too big",
363: __func__, sc->channels_alloc);
364: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
365: sc->channels_alloc + 10, sizeof(*sc->channels));
366: sc->channels_alloc += 10;
367: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 368: }
1.113 markus 369: /* Initialize and return new channel. */
1.367 djm 370: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
371: if ((c->input = sshbuf_new()) == NULL ||
372: (c->output = sshbuf_new()) == NULL ||
373: (c->extended = sshbuf_new()) == NULL)
374: fatal("%s: sshbuf_new failed", __func__);
1.159 markus 375: c->ostate = CHAN_OUTPUT_OPEN;
376: c->istate = CHAN_INPUT_OPEN;
1.367 djm 377: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 378: c->self = found;
379: c->type = type;
1.41 markus 380: c->ctype = ctype;
1.51 markus 381: c->local_window = window;
382: c->local_window_max = window;
383: c->local_maxpacket = maxpack;
1.190 markus 384: c->remote_name = xstrdup(remote_name);
1.302 djm 385: c->ctl_chan = -1;
1.299 markus 386: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 387: TAILQ_INIT(&c->status_confirms);
1.25 markus 388: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 389: return c;
1.1 deraadt 390: }
1.52 markus 391:
1.367 djm 392: static void
393: channel_find_maxfd(struct ssh_channels *sc)
1.132 markus 394: {
1.209 avsm 395: u_int i;
396: int max = 0;
1.132 markus 397: Channel *c;
398:
1.367 djm 399: for (i = 0; i < sc->channels_alloc; i++) {
400: c = sc->channels[i];
1.132 markus 401: if (c != NULL) {
1.352 deraadt 402: max = MAXIMUM(max, c->rfd);
403: max = MAXIMUM(max, c->wfd);
404: max = MAXIMUM(max, c->efd);
1.132 markus 405: }
406: }
1.367 djm 407: sc->channel_max_fd = max;
1.132 markus 408: }
409:
410: int
1.367 djm 411: channel_close_fd(struct ssh *ssh, int *fdp)
1.132 markus 412: {
1.367 djm 413: struct ssh_channels *sc = ssh->chanctxt;
1.132 markus 414: int ret = 0, fd = *fdp;
415:
416: if (fd != -1) {
417: ret = close(fd);
418: *fdp = -1;
1.367 djm 419: if (fd == sc->channel_max_fd)
420: channel_find_maxfd(sc);
1.132 markus 421: }
422: return ret;
423: }
424:
1.52 markus 425: /* Close all channel fd/socket. */
1.127 itojun 426: static void
1.367 djm 427: channel_close_fds(struct ssh *ssh, Channel *c)
428: {
429: channel_close_fd(ssh, &c->sock);
430: channel_close_fd(ssh, &c->rfd);
431: channel_close_fd(ssh, &c->wfd);
432: channel_close_fd(ssh, &c->efd);
433: }
434:
435: static void
436: fwd_perm_clear(ForwardPermission *fp)
1.52 markus 437: {
1.367 djm 438: free(fp->host_to_connect);
439: free(fp->listen_host);
440: free(fp->listen_path);
441: bzero(fp, sizeof(*fp));
442: }
443:
444: enum { FWDPERM_USER, FWDPERM_ADMIN };
445:
446: static int
447: fwd_perm_list_add(struct ssh *ssh, int which,
448: const char *host_to_connect, int port_to_connect,
449: const char *listen_host, const char *listen_path, int listen_port,
450: Channel *downstream)
451: {
452: ForwardPermission **fpl;
453: u_int n, *nfpl;
454:
455: switch (which) {
456: case FWDPERM_USER:
457: fpl = &ssh->chanctxt->permitted_opens;
458: nfpl = &ssh->chanctxt->num_permitted_opens;
459: break;
460: case FWDPERM_ADMIN:
461: fpl = &ssh->chanctxt->permitted_adm_opens;
462: nfpl = &ssh->chanctxt->num_adm_permitted_opens;
463: break;
464: default:
465: fatal("%s: invalid list %d", __func__, which);
466: }
467:
468: if (*nfpl >= INT_MAX)
469: fatal("%s: overflow", __func__);
470:
471: *fpl = xrecallocarray(*fpl, *nfpl, *nfpl + 1, sizeof(**fpl));
472: n = (*nfpl)++;
473: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
474: (*fpl)[n].host_to_connect = MAYBE_DUP(host_to_connect);
475: (*fpl)[n].port_to_connect = port_to_connect;
476: (*fpl)[n].listen_host = MAYBE_DUP(listen_host);
477: (*fpl)[n].listen_path = MAYBE_DUP(listen_path);
478: (*fpl)[n].listen_port = listen_port;
479: (*fpl)[n].downstream = downstream;
480: #undef MAYBE_DUP
481: return (int)n;
482: }
483:
484: static void
485: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
486: {
487: struct ssh_channels *sc = ssh->chanctxt;
488: ForwardPermission *fp;
489: int r;
490: u_int i;
491:
492: for (i = 0; i < sc->num_permitted_opens; i++) {
493: fp = &sc->permitted_opens[i];
494: if (fp->downstream != c)
495: continue;
496:
497: /* cancel on the server, since mux client is gone */
498: debug("channel %d: cleanup remote forward for %s:%u",
499: c->self, fp->listen_host, fp->listen_port);
500: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
501: (r = sshpkt_put_cstring(ssh,
502: "cancel-tcpip-forward")) != 0 ||
503: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
504: (r = sshpkt_put_cstring(ssh,
505: channel_rfwd_bind_host(fp->listen_host))) != 0 ||
506: (r = sshpkt_put_u32(ssh, fp->listen_port)) != 0 ||
507: (r = sshpkt_send(ssh)) != 0) {
508: fatal("%s: channel %i: %s", __func__,
509: c->self, ssh_err(r));
510: }
511: fwd_perm_clear(fp); /* unregister */
512: }
1.121 markus 513: }
514:
515: /* Free the channel and close its fd/socket. */
516: void
1.367 djm 517: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 518: {
1.367 djm 519: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 520: char *s;
1.209 avsm 521: u_int i, n;
1.354 markus 522: Channel *other;
1.275 djm 523: struct channel_confirm *cc;
1.121 markus 524:
1.367 djm 525: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
526: if ((other = sc->channels[i]) == NULL)
527: continue;
528: n++;
529: /* detach from mux client and prepare for closing */
530: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
531: other->type == SSH_CHANNEL_MUX_PROXY &&
532: other->mux_ctx == c) {
533: other->mux_ctx = NULL;
534: other->type = SSH_CHANNEL_OPEN;
535: other->istate = CHAN_INPUT_CLOSED;
536: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 537: }
538: }
1.209 avsm 539: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 540: c->remote_name ? c->remote_name : "???", n);
541:
1.367 djm 542: if (c->type == SSH_CHANNEL_MUX_CLIENT)
543: mux_remove_remote_forwardings(ssh, c);
1.354 markus 544:
1.367 djm 545: s = channel_open_message(ssh);
1.194 markus 546: debug3("channel %d: status: %s", c->self, s);
1.321 djm 547: free(s);
1.121 markus 548:
1.367 djm 549: channel_close_fds(ssh, c);
550: sshbuf_free(c->input);
551: sshbuf_free(c->output);
552: sshbuf_free(c->extended);
553: c->input = c->output = c->extended = NULL;
1.321 djm 554: free(c->remote_name);
555: c->remote_name = NULL;
556: free(c->path);
557: c->path = NULL;
558: free(c->listening_addr);
559: c->listening_addr = NULL;
1.275 djm 560: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
561: if (cc->abandon_cb != NULL)
1.367 djm 562: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 563: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 564: explicit_bzero(cc, sizeof(*cc));
1.321 djm 565: free(cc);
1.275 djm 566: }
1.280 djm 567: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 568: c->filter_cleanup(ssh, c->self, c->filter_ctx);
569: sc->channels[c->self] = NULL;
1.371 millert 570: explicit_bzero(c, sizeof(*c));
1.321 djm 571: free(c);
1.121 markus 572: }
573:
574: void
1.367 djm 575: channel_free_all(struct ssh *ssh)
1.121 markus 576: {
1.209 avsm 577: u_int i;
1.121 markus 578:
1.367 djm 579: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
580: if (ssh->chanctxt->channels[i] != NULL)
581: channel_free(ssh, ssh->chanctxt->channels[i]);
1.131 markus 582: }
583:
1.121 markus 584: /*
585: * Closes the sockets/fds of all channels. This is used to close extra file
586: * descriptors after a fork.
587: */
588: void
1.367 djm 589: channel_close_all(struct ssh *ssh)
1.121 markus 590: {
1.209 avsm 591: u_int i;
1.121 markus 592:
1.367 djm 593: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
594: if (ssh->chanctxt->channels[i] != NULL)
595: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 596: }
597:
598: /*
1.131 markus 599: * Stop listening to channels.
600: */
601: void
1.367 djm 602: channel_stop_listening(struct ssh *ssh)
1.131 markus 603: {
1.209 avsm 604: u_int i;
1.131 markus 605: Channel *c;
606:
1.367 djm 607: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
608: c = ssh->chanctxt->channels[i];
1.131 markus 609: if (c != NULL) {
610: switch (c->type) {
611: case SSH_CHANNEL_AUTH_SOCKET:
612: case SSH_CHANNEL_PORT_LISTENER:
613: case SSH_CHANNEL_RPORT_LISTENER:
614: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 615: case SSH_CHANNEL_UNIX_LISTENER:
616: case SSH_CHANNEL_RUNIX_LISTENER:
1.367 djm 617: channel_close_fd(ssh, &c->sock);
618: channel_free(ssh, c);
1.131 markus 619: break;
620: }
621: }
622: }
623: }
624:
625: /*
1.121 markus 626: * Returns true if no channel has too much buffered data, and false if one or
627: * more channel is overfull.
628: */
629: int
1.367 djm 630: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 631: {
632: u_int i;
1.367 djm 633: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 634: Channel *c;
635:
1.367 djm 636: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
637: c = ssh->chanctxt->channels[i];
638: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
639: continue;
640: if (sshbuf_len(c->output) > maxsize) {
641: debug2("channel %d: big output buffer %zu > %u",
642: c->self, sshbuf_len(c->output), maxsize);
643: return 0;
1.121 markus 644: }
645: }
646: return 1;
647: }
648:
649: /* Returns true if any channel is still open. */
650: int
1.367 djm 651: channel_still_open(struct ssh *ssh)
1.121 markus 652: {
1.209 avsm 653: u_int i;
1.121 markus 654: Channel *c;
655:
1.367 djm 656: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
657: c = ssh->chanctxt->channels[i];
1.121 markus 658: if (c == NULL)
659: continue;
660: switch (c->type) {
661: case SSH_CHANNEL_X11_LISTENER:
662: case SSH_CHANNEL_PORT_LISTENER:
663: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 664: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 665: case SSH_CHANNEL_CLOSED:
666: case SSH_CHANNEL_AUTH_SOCKET:
667: case SSH_CHANNEL_DYNAMIC:
1.372 ! markus 668: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 669: case SSH_CHANNEL_CONNECTING:
670: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 671: case SSH_CHANNEL_ABANDONED:
1.336 millert 672: case SSH_CHANNEL_UNIX_LISTENER:
673: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 674: continue;
675: case SSH_CHANNEL_LARVAL:
676: continue;
677: case SSH_CHANNEL_OPENING:
678: case SSH_CHANNEL_OPEN:
1.372 ! markus 679: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 680: case SSH_CHANNEL_X11_OPEN:
1.302 djm 681: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 682: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 683: return 1;
684: default:
1.358 djm 685: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 686: /* NOTREACHED */
687: }
688: }
689: return 0;
690: }
691:
692: /* Returns the id of an open channel suitable for keepaliving */
693: int
1.367 djm 694: channel_find_open(struct ssh *ssh)
1.121 markus 695: {
1.209 avsm 696: u_int i;
1.121 markus 697: Channel *c;
698:
1.367 djm 699: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
700: c = ssh->chanctxt->channels[i];
1.368 djm 701: if (c == NULL || !c->have_remote_id)
1.121 markus 702: continue;
703: switch (c->type) {
704: case SSH_CHANNEL_CLOSED:
705: case SSH_CHANNEL_DYNAMIC:
1.372 ! markus 706: case SSH_CHANNEL_RDYNAMIC_OPEN:
! 707: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 708: case SSH_CHANNEL_X11_LISTENER:
709: case SSH_CHANNEL_PORT_LISTENER:
710: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 711: case SSH_CHANNEL_MUX_LISTENER:
712: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 713: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 714: case SSH_CHANNEL_OPENING:
715: case SSH_CHANNEL_CONNECTING:
716: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 717: case SSH_CHANNEL_ABANDONED:
1.336 millert 718: case SSH_CHANNEL_UNIX_LISTENER:
719: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 720: continue;
721: case SSH_CHANNEL_LARVAL:
722: case SSH_CHANNEL_AUTH_SOCKET:
723: case SSH_CHANNEL_OPEN:
724: case SSH_CHANNEL_X11_OPEN:
725: return i;
726: default:
1.358 djm 727: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 728: /* NOTREACHED */
729: }
730: }
731: return -1;
732: }
733:
734: /*
735: * Returns a message describing the currently open forwarded connections,
736: * suitable for sending to the client. The message contains crlf pairs for
737: * newlines.
738: */
739: char *
1.367 djm 740: channel_open_message(struct ssh *ssh)
1.121 markus 741: {
1.367 djm 742: struct sshbuf *buf;
1.121 markus 743: Channel *c;
1.209 avsm 744: u_int i;
1.367 djm 745: int r;
746: char *ret;
1.121 markus 747:
1.367 djm 748: if ((buf = sshbuf_new()) == NULL)
749: fatal("%s: sshbuf_new", __func__);
750: if ((r = sshbuf_putf(buf,
751: "The following connections are open:\r\n")) != 0)
752: fatal("%s: sshbuf_putf: %s", __func__, ssh_err(r));
753: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
754: c = ssh->chanctxt->channels[i];
1.121 markus 755: if (c == NULL)
756: continue;
757: switch (c->type) {
758: case SSH_CHANNEL_X11_LISTENER:
759: case SSH_CHANNEL_PORT_LISTENER:
760: case SSH_CHANNEL_RPORT_LISTENER:
761: case SSH_CHANNEL_CLOSED:
762: case SSH_CHANNEL_AUTH_SOCKET:
763: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 764: case SSH_CHANNEL_ABANDONED:
1.302 djm 765: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 766: case SSH_CHANNEL_UNIX_LISTENER:
767: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 768: continue;
769: case SSH_CHANNEL_LARVAL:
770: case SSH_CHANNEL_OPENING:
771: case SSH_CHANNEL_CONNECTING:
772: case SSH_CHANNEL_DYNAMIC:
1.372 ! markus 773: case SSH_CHANNEL_RDYNAMIC_OPEN:
! 774: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 775: case SSH_CHANNEL_OPEN:
776: case SSH_CHANNEL_X11_OPEN:
1.354 markus 777: case SSH_CHANNEL_MUX_PROXY:
778: case SSH_CHANNEL_MUX_CLIENT:
1.367 djm 779: if ((r = sshbuf_putf(buf, " #%d %.300s "
1.368 djm 780: "(t%d %s%u i%u/%zu o%u/%zu fd %d/%d cc %d)\r\n",
1.121 markus 781: c->self, c->remote_name,
1.368 djm 782: c->type,
783: c->have_remote_id ? "r" : "nr", c->remote_id,
1.367 djm 784: c->istate, sshbuf_len(c->input),
785: c->ostate, sshbuf_len(c->output),
786: c->rfd, c->wfd, c->ctl_chan)) != 0)
787: fatal("%s: sshbuf_putf: %s",
788: __func__, ssh_err(r));
1.121 markus 789: continue;
790: default:
1.367 djm 791: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 792: /* NOTREACHED */
793: }
794: }
1.367 djm 795: if ((ret = sshbuf_dup_string(buf)) == NULL)
796: fatal("%s: sshbuf_dup_string", __func__);
797: sshbuf_free(buf);
798: return ret;
799: }
800:
801: static void
802: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
803: {
804: int r;
805:
806: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
807: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
808: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
809: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
810: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
811: fatal("%s: channel %i: open: %s", where, c->self, ssh_err(r));
812: }
1.121 markus 813: }
814:
815: void
1.367 djm 816: channel_send_open(struct ssh *ssh, int id)
1.121 markus 817: {
1.367 djm 818: Channel *c = channel_lookup(ssh, id);
819: int r;
1.180 deraadt 820:
1.121 markus 821: if (c == NULL) {
1.188 itojun 822: logit("channel_send_open: %d: bad id", id);
1.121 markus 823: return;
824: }
1.184 markus 825: debug2("channel %d: send open", id);
1.367 djm 826: open_preamble(ssh, __func__, c, c->ctype);
827: if ((r = sshpkt_send(ssh)) != 0)
828: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.121 markus 829: }
830:
831: void
1.367 djm 832: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 833: {
1.367 djm 834: Channel *c = channel_lookup(ssh, id);
835: int r;
1.180 deraadt 836:
1.121 markus 837: if (c == NULL) {
1.367 djm 838: logit("%s: %d: unknown channel id", __func__, id);
1.121 markus 839: return;
840: }
1.368 djm 841: if (!c->have_remote_id)
842: fatal(":%s: channel %d: no remote id", __func__, c->self);
843:
1.204 djm 844: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 845: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
846: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
847: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
848: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
849: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
850: }
1.121 markus 851: }
1.241 deraadt 852:
1.121 markus 853: void
1.367 djm 854: channel_register_status_confirm(struct ssh *ssh, int id,
855: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 856: {
857: struct channel_confirm *cc;
858: Channel *c;
859:
1.367 djm 860: if ((c = channel_lookup(ssh, id)) == NULL)
861: fatal("%s: %d: bad id", __func__, id);
1.275 djm 862:
1.327 djm 863: cc = xcalloc(1, sizeof(*cc));
1.275 djm 864: cc->cb = cb;
865: cc->abandon_cb = abandon_cb;
866: cc->ctx = ctx;
867: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
868: }
869:
870: void
1.367 djm 871: channel_register_open_confirm(struct ssh *ssh, int id,
872: channel_open_fn *fn, void *ctx)
1.121 markus 873: {
1.367 djm 874: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 875:
1.121 markus 876: if (c == NULL) {
1.367 djm 877: logit("%s: %d: bad id", __func__, id);
1.121 markus 878: return;
879: }
1.275 djm 880: c->open_confirm = fn;
881: c->open_confirm_ctx = ctx;
1.121 markus 882: }
1.241 deraadt 883:
1.121 markus 884: void
1.367 djm 885: channel_register_cleanup(struct ssh *ssh, int id,
886: channel_callback_fn *fn, int do_close)
1.121 markus 887: {
1.367 djm 888: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 889:
1.121 markus 890: if (c == NULL) {
1.367 djm 891: logit("%s: %d: bad id", __func__, id);
1.121 markus 892: return;
893: }
1.131 markus 894: c->detach_user = fn;
1.225 djm 895: c->detach_close = do_close;
1.121 markus 896: }
1.241 deraadt 897:
1.121 markus 898: void
1.367 djm 899: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 900: {
1.367 djm 901: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 902:
1.121 markus 903: if (c == NULL) {
1.367 djm 904: logit("%s: %d: bad id", __func__, id);
1.121 markus 905: return;
1.52 markus 906: }
1.131 markus 907: c->detach_user = NULL;
1.225 djm 908: c->detach_close = 0;
1.121 markus 909: }
1.241 deraadt 910:
1.121 markus 911: void
1.367 djm 912: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 913: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 914: {
1.367 djm 915: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 916:
1.121 markus 917: if (c == NULL) {
1.367 djm 918: logit("%s: %d: bad id", __func__, id);
1.121 markus 919: return;
1.52 markus 920: }
1.231 reyk 921: c->input_filter = ifn;
922: c->output_filter = ofn;
1.279 djm 923: c->filter_ctx = ctx;
1.280 djm 924: c->filter_cleanup = cfn;
1.52 markus 925: }
926:
1.49 markus 927: void
1.367 djm 928: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 929: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 930: {
1.367 djm 931: Channel *c = channel_lookup(ssh, id);
932: int r;
1.180 deraadt 933:
1.121 markus 934: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
935: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 936: if (!c->have_remote_id)
937: fatal(":%s: channel %d: no remote id", __func__, c->self);
938:
1.367 djm 939: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 940: c->type = SSH_CHANNEL_OPEN;
1.168 markus 941: c->local_window = c->local_window_max = window_max;
1.367 djm 942:
943: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
944: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
945: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
946: (r = sshpkt_send(ssh)) != 0)
947: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.1 deraadt 948: }
949:
1.127 itojun 950: static void
1.367 djm 951: channel_pre_listener(struct ssh *ssh, Channel *c,
952: fd_set *readset, fd_set *writeset)
1.41 markus 953: {
954: FD_SET(c->sock, readset);
955: }
956:
1.127 itojun 957: static void
1.367 djm 958: channel_pre_connecting(struct ssh *ssh, Channel *c,
959: fd_set *readset, fd_set *writeset)
1.75 markus 960: {
961: debug3("channel %d: waiting for connection", c->self);
962: FD_SET(c->sock, writeset);
963: }
964:
1.127 itojun 965: static void
1.367 djm 966: channel_pre_open(struct ssh *ssh, Channel *c,
967: fd_set *readset, fd_set *writeset)
1.41 markus 968: {
1.44 markus 969: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 970: c->remote_window > 0 &&
1.367 djm 971: sshbuf_len(c->input) < c->remote_window &&
972: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.44 markus 973: FD_SET(c->rfd, readset);
974: if (c->ostate == CHAN_OUTPUT_OPEN ||
975: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 976: if (sshbuf_len(c->output) > 0) {
1.44 markus 977: FD_SET(c->wfd, writeset);
978: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 979: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 980: debug2("channel %d: "
981: "obuf_empty delayed efd %d/(%zu)", c->self,
982: c->efd, sshbuf_len(c->extended));
1.172 markus 983: else
1.367 djm 984: chan_obuf_empty(ssh, c);
1.44 markus 985: }
986: }
987: /** XXX check close conditions, too */
1.358 djm 988: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
989: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 990: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 991: sshbuf_len(c->extended) > 0)
1.44 markus 992: FD_SET(c->efd, writeset);
1.306 djm 993: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
994: (c->extended_usage == CHAN_EXTENDED_READ ||
995: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 996: sshbuf_len(c->extended) < c->remote_window)
1.44 markus 997: FD_SET(c->efd, readset);
998: }
1.204 djm 999: /* XXX: What about efd? races? */
1.44 markus 1000: }
1001:
1.41 markus 1002: /*
1003: * This is a special state for X11 authentication spoofing. An opened X11
1004: * connection (when authentication spoofing is being done) remains in this
1005: * state until the first packet has been completely read. The authentication
1006: * data in that packet is then substituted by the real data if it matches the
1007: * fake data, and the channel is put into normal mode.
1.51 markus 1008: * XXX All this happens at the client side.
1.121 markus 1009: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1010: */
1.127 itojun 1011: static int
1.367 djm 1012: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1013: {
1.367 djm 1014: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1015: u_char *ucp;
1016: u_int proto_len, data_len;
1.25 markus 1017:
1.347 djm 1018: /* Is this being called after the refusal deadline? */
1.367 djm 1019: if (sc->x11_refuse_time != 0 &&
1020: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1021: verbose("Rejected X11 connection after ForwardX11Timeout "
1022: "expired");
1023: return -1;
1024: }
1025:
1.41 markus 1026: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1027: if (sshbuf_len(b) < 12)
1.41 markus 1028: return 0;
1029:
1030: /* Parse the lengths of variable-length fields. */
1.367 djm 1031: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1032: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1033: proto_len = 256 * ucp[6] + ucp[7];
1034: data_len = 256 * ucp[8] + ucp[9];
1035: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1036: proto_len = ucp[6] + 256 * ucp[7];
1037: data_len = ucp[8] + 256 * ucp[9];
1038: } else {
1.194 markus 1039: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1040: ucp[0]);
1.41 markus 1041: return -1;
1042: }
1043:
1044: /* Check if the whole packet is in buffer. */
1.367 djm 1045: if (sshbuf_len(b) <
1.41 markus 1046: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1047: return 0;
1048:
1049: /* Check if authentication protocol matches. */
1.367 djm 1050: if (proto_len != strlen(sc->x11_saved_proto) ||
1051: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1052: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1053: return -1;
1054: }
1055: /* Check if authentication data matches our fake data. */
1.367 djm 1056: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1057: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1058: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1059: debug2("X11 auth data does not match fake data.");
1.41 markus 1060: return -1;
1061: }
1062: /* Check fake data length */
1.367 djm 1063: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1064: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1065: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1066: return -1;
1067: }
1068: /*
1069: * Received authentication protocol and data match
1070: * our fake data. Substitute the fake data with real
1071: * data.
1072: */
1073: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1074: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1075: return 1;
1076: }
1077:
1.127 itojun 1078: static void
1.367 djm 1079: channel_pre_x11_open(struct ssh *ssh, Channel *c,
1080: fd_set *readset, fd_set *writeset)
1.41 markus 1081: {
1.367 djm 1082: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1083:
1084: /* c->force_drain = 1; */
1085:
1.41 markus 1086: if (ret == 1) {
1087: c->type = SSH_CHANNEL_OPEN;
1.367 djm 1088: channel_pre_open(ssh, c, readset, writeset);
1.41 markus 1089: } else if (ret == -1) {
1.188 itojun 1090: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1091: debug2("X11 rejected %d i%d/o%d",
1092: c->self, c->istate, c->ostate);
1093: chan_read_failed(ssh, c);
1094: sshbuf_reset(c->input);
1095: chan_ibuf_empty(ssh, c);
1096: sshbuf_reset(c->output);
1097: chan_write_failed(ssh, c);
1.194 markus 1098: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1099: }
1100: }
1.25 markus 1101:
1.302 djm 1102: static void
1.367 djm 1103: channel_pre_mux_client(struct ssh *ssh,
1104: Channel *c, fd_set *readset, fd_set *writeset)
1.302 djm 1105: {
1.304 djm 1106: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1107: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.302 djm 1108: FD_SET(c->rfd, readset);
1109: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1110: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1111: sshbuf_reset(c->input);
1112: chan_ibuf_empty(ssh, c);
1.302 djm 1113: /* Start output drain. XXX just kill chan? */
1.367 djm 1114: chan_rcvd_oclose(ssh, c);
1.302 djm 1115: }
1116: if (c->ostate == CHAN_OUTPUT_OPEN ||
1117: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1118: if (sshbuf_len(c->output) > 0)
1.302 djm 1119: FD_SET(c->wfd, writeset);
1120: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1121: chan_obuf_empty(ssh, c);
1.302 djm 1122: }
1123: }
1124:
1.104 markus 1125: /* try to decode a socks4 header */
1.127 itojun 1126: static int
1.372 ! markus 1127: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1128: {
1.367 djm 1129: const u_char *p;
1130: char *host;
1.292 djm 1131: u_int len, have, i, found, need;
1.148 deraadt 1132: char username[256];
1.103 markus 1133: struct {
1134: u_int8_t version;
1135: u_int8_t command;
1136: u_int16_t dest_port;
1.104 markus 1137: struct in_addr dest_addr;
1.103 markus 1138: } s4_req, s4_rsp;
1.367 djm 1139: int r;
1.103 markus 1140:
1.104 markus 1141: debug2("channel %d: decode socks4", c->self);
1.109 markus 1142:
1.372 ! markus 1143: have = sshbuf_len(input);
1.109 markus 1144: len = sizeof(s4_req);
1145: if (have < len)
1146: return 0;
1.372 ! markus 1147: p = sshbuf_ptr(input);
1.292 djm 1148:
1149: need = 1;
1150: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1151: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1152: debug2("channel %d: socks4a request", c->self);
1153: /* ... and needs an extra string (the hostname) */
1154: need = 2;
1155: }
1156: /* Check for terminating NUL on the string(s) */
1.109 markus 1157: for (found = 0, i = len; i < have; i++) {
1158: if (p[i] == '\0') {
1.292 djm 1159: found++;
1160: if (found == need)
1161: break;
1.109 markus 1162: }
1163: if (i > 1024) {
1164: /* the peer is probably sending garbage */
1165: debug("channel %d: decode socks4: too long",
1166: c->self);
1167: return -1;
1168: }
1169: }
1.292 djm 1170: if (found < need)
1.109 markus 1171: return 0;
1.372 ! markus 1172: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
! 1173: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
! 1174: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
! 1175: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.367 djm 1176: debug("channels %d: decode socks4: %s", c->self, ssh_err(r));
1177: return -1;
1178: }
1.372 ! markus 1179: have = sshbuf_len(input);
! 1180: p = sshbuf_ptr(input);
1.364 djm 1181: if (memchr(p, '\0', have) == NULL) {
1182: error("channel %d: decode socks4: user not nul terminated",
1.331 djm 1183: c->self);
1.364 djm 1184: return -1;
1185: }
1.103 markus 1186: len = strlen(p);
1.106 markus 1187: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1188: len++; /* trailing '\0' */
1.103 markus 1189: strlcpy(username, p, sizeof(username));
1.372 ! markus 1190: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1191: fatal("%s: channel %d: consume: %s", __func__,
1192: c->self, ssh_err(r));
1193: }
1.321 djm 1194: free(c->path);
1195: c->path = NULL;
1.292 djm 1196: if (need == 1) { /* SOCKS4: one string */
1197: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1198: c->path = xstrdup(host);
1.292 djm 1199: } else { /* SOCKS4A: two strings */
1.372 ! markus 1200: have = sshbuf_len(input);
! 1201: p = sshbuf_ptr(input);
1.364 djm 1202: if (memchr(p, '\0', have) == NULL) {
1203: error("channel %d: decode socks4a: host not nul "
1204: "terminated", c->self);
1205: return -1;
1206: }
1.292 djm 1207: len = strlen(p);
1208: debug2("channel %d: decode socks4a: host %s/%d",
1209: c->self, p, len);
1210: len++; /* trailing '\0' */
1.293 djm 1211: if (len > NI_MAXHOST) {
1.292 djm 1212: error("channel %d: hostname \"%.100s\" too long",
1213: c->self, p);
1214: return -1;
1215: }
1.293 djm 1216: c->path = xstrdup(p);
1.372 ! markus 1217: if ((r = sshbuf_consume(input, len)) != 0) {
1.367 djm 1218: fatal("%s: channel %d: consume: %s", __func__,
1219: c->self, ssh_err(r));
1220: }
1.292 djm 1221: }
1.103 markus 1222: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1223:
1.194 markus 1224: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1225: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1226:
1.104 markus 1227: if (s4_req.command != 1) {
1.292 djm 1228: debug("channel %d: cannot handle: %s cn %d",
1229: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1230: return -1;
1.103 markus 1231: }
1.104 markus 1232: s4_rsp.version = 0; /* vn: 0 for reply */
1233: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1234: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1235: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.372 ! markus 1236: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0) {
1.367 djm 1237: fatal("%s: channel %d: append reply: %s", __func__,
1238: c->self, ssh_err(r));
1239: }
1.104 markus 1240: return 1;
1241: }
1242:
1.193 markus 1243: /* try to decode a socks5 header */
1244: #define SSH_SOCKS5_AUTHDONE 0x1000
1245: #define SSH_SOCKS5_NOAUTH 0x00
1246: #define SSH_SOCKS5_IPV4 0x01
1247: #define SSH_SOCKS5_DOMAIN 0x03
1248: #define SSH_SOCKS5_IPV6 0x04
1249: #define SSH_SOCKS5_CONNECT 0x01
1250: #define SSH_SOCKS5_SUCCESS 0x00
1251:
1252: static int
1.372 ! markus 1253: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1254: {
1.367 djm 1255: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1256: struct {
1257: u_int8_t version;
1258: u_int8_t command;
1259: u_int8_t reserved;
1260: u_int8_t atyp;
1261: } s5_req, s5_rsp;
1262: u_int16_t dest_port;
1.324 djm 1263: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1264: const u_char *p;
1.252 djm 1265: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1266: int r;
1.193 markus 1267:
1268: debug2("channel %d: decode socks5", c->self);
1.372 ! markus 1269: p = sshbuf_ptr(input);
1.193 markus 1270: if (p[0] != 0x05)
1271: return -1;
1.372 ! markus 1272: have = sshbuf_len(input);
1.193 markus 1273: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1274: /* format: ver | nmethods | methods */
1.198 djm 1275: if (have < 2)
1.193 markus 1276: return 0;
1277: nmethods = p[1];
1278: if (have < nmethods + 2)
1279: return 0;
1280: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1281: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1282: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1283: found = 1;
1284: break;
1285: }
1286: }
1287: if (!found) {
1288: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1289: c->self);
1290: return -1;
1291: }
1.372 ! markus 1292: if ((r = sshbuf_consume(input, nmethods + 2)) != 0) {
1.367 djm 1293: fatal("%s: channel %d: consume: %s", __func__,
1294: c->self, ssh_err(r));
1295: }
1296: /* version, method */
1.372 ! markus 1297: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
! 1298: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0) {
1.367 djm 1299: fatal("%s: channel %d: append reply: %s", __func__,
1300: c->self, ssh_err(r));
1301: }
1.193 markus 1302: c->flags |= SSH_SOCKS5_AUTHDONE;
1303: debug2("channel %d: socks5 auth done", c->self);
1304: return 0; /* need more */
1305: }
1306: debug2("channel %d: socks5 post auth", c->self);
1307: if (have < sizeof(s5_req)+1)
1308: return 0; /* need more */
1.247 deraadt 1309: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1310: if (s5_req.version != 0x05 ||
1311: s5_req.command != SSH_SOCKS5_CONNECT ||
1312: s5_req.reserved != 0x00) {
1.194 markus 1313: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1314: return -1;
1315: }
1.213 deraadt 1316: switch (s5_req.atyp){
1.193 markus 1317: case SSH_SOCKS5_IPV4:
1318: addrlen = 4;
1319: af = AF_INET;
1320: break;
1321: case SSH_SOCKS5_DOMAIN:
1322: addrlen = p[sizeof(s5_req)];
1323: af = -1;
1324: break;
1325: case SSH_SOCKS5_IPV6:
1326: addrlen = 16;
1327: af = AF_INET6;
1328: break;
1329: default:
1.194 markus 1330: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1331: return -1;
1332: }
1.252 djm 1333: need = sizeof(s5_req) + addrlen + 2;
1334: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1335: need++;
1336: if (have < need)
1.193 markus 1337: return 0;
1.372 ! markus 1338: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0) {
1.367 djm 1339: fatal("%s: channel %d: consume: %s", __func__,
1340: c->self, ssh_err(r));
1341: }
1342: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1343: /* host string length */
1.372 ! markus 1344: if ((r = sshbuf_consume(input, 1)) != 0) {
1.367 djm 1345: fatal("%s: channel %d: consume: %s", __func__,
1346: c->self, ssh_err(r));
1347: }
1348: }
1.372 ! markus 1349: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
! 1350: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.367 djm 1351: debug("channel %d: parse addr/port: %s", c->self, ssh_err(r));
1352: return -1;
1353: }
1.193 markus 1354: dest_addr[addrlen] = '\0';
1.321 djm 1355: free(c->path);
1356: c->path = NULL;
1.293 djm 1357: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1358: if (addrlen >= NI_MAXHOST) {
1.293 djm 1359: error("channel %d: dynamic request: socks5 hostname "
1360: "\"%.100s\" too long", c->self, dest_addr);
1361: return -1;
1362: }
1363: c->path = xstrdup(dest_addr);
1364: } else {
1365: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1366: return -1;
1367: c->path = xstrdup(ntop);
1368: }
1.193 markus 1369: c->host_port = ntohs(dest_port);
1.198 djm 1370:
1.194 markus 1371: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1372: c->self, c->path, c->host_port, s5_req.command);
1373:
1374: s5_rsp.version = 0x05;
1375: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1376: s5_rsp.reserved = 0; /* ignored */
1377: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1378: dest_port = 0; /* ignored */
1379:
1.372 ! markus 1380: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
! 1381: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
! 1382: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.367 djm 1383: fatal("%s: channel %d: append reply: %s", __func__,
1384: c->self, ssh_err(r));
1.193 markus 1385: return 1;
1.301 dtucker 1386: }
1387:
1388: Channel *
1.367 djm 1389: channel_connect_stdio_fwd(struct ssh *ssh,
1390: const char *host_to_connect, u_short port_to_connect, int in, int out)
1.301 dtucker 1391: {
1392: Channel *c;
1393:
1.367 djm 1394: debug("%s %s:%d", __func__, host_to_connect, port_to_connect);
1.301 dtucker 1395:
1.367 djm 1396: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1397: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1398: 0, "stdio-forward", /*nonblock*/0);
1399:
1400: c->path = xstrdup(host_to_connect);
1401: c->host_port = port_to_connect;
1402: c->listening_port = 0;
1403: c->force_drain = 1;
1404:
1.367 djm 1405: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1406: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1407:
1408: return c;
1.193 markus 1409: }
1410:
1.104 markus 1411: /* dynamic port forwarding */
1.127 itojun 1412: static void
1.367 djm 1413: channel_pre_dynamic(struct ssh *ssh, Channel *c,
1414: fd_set *readset, fd_set *writeset)
1.104 markus 1415: {
1.367 djm 1416: const u_char *p;
1.217 djm 1417: u_int have;
1418: int ret;
1.103 markus 1419:
1.367 djm 1420: have = sshbuf_len(c->input);
1.104 markus 1421: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1422: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1423: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1424: if (have < 3) {
1.104 markus 1425: /* need more */
1426: FD_SET(c->sock, readset);
1427: return;
1428: }
1429: /* try to guess the protocol */
1.367 djm 1430: p = sshbuf_ptr(c->input);
1431: /* XXX sshbuf_peek_u8? */
1.104 markus 1432: switch (p[0]) {
1433: case 0x04:
1.372 ! markus 1434: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1435: break;
1436: case 0x05:
1.372 ! markus 1437: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1438: break;
1439: default:
1440: ret = -1;
1441: break;
1442: }
1443: if (ret < 0) {
1.367 djm 1444: chan_mark_dead(ssh, c);
1.104 markus 1445: } else if (ret == 0) {
1446: debug2("channel %d: pre_dynamic: need more", c->self);
1447: /* need more */
1448: FD_SET(c->sock, readset);
1.372 ! markus 1449: if (sshbuf_len(c->output))
! 1450: FD_SET(c->sock, writeset);
1.104 markus 1451: } else {
1452: /* switch to the next state */
1453: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1454: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1455: }
1.103 markus 1456: }
1457:
1.372 ! markus 1458: /* simulate read-error */
! 1459: static void
! 1460: rdynamic_close(struct ssh *ssh, Channel *c)
! 1461: {
! 1462: c->type = SSH_CHANNEL_OPEN;
! 1463: chan_read_failed(ssh, c);
! 1464: sshbuf_reset(c->input);
! 1465: chan_ibuf_empty(ssh, c);
! 1466: sshbuf_reset(c->output);
! 1467: chan_write_failed(ssh, c);
! 1468: }
! 1469:
! 1470: /* reverse dynamic port forwarding */
! 1471: static void
! 1472: channel_before_prepare_select_rdynamic(struct ssh *ssh, Channel *c)
! 1473: {
! 1474: const u_char *p;
! 1475: u_int have, len;
! 1476: int r, ret;
! 1477:
! 1478: have = sshbuf_len(c->output);
! 1479: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
! 1480: /* sshbuf_dump(c->output, stderr); */
! 1481: /* EOF received */
! 1482: if (c->flags & CHAN_EOF_RCVD) {
! 1483: if ((r = sshbuf_consume(c->output, have)) != 0) {
! 1484: fatal("%s: channel %d: consume: %s",
! 1485: __func__, c->self, ssh_err(r));
! 1486: }
! 1487: rdynamic_close(ssh, c);
! 1488: return;
! 1489: }
! 1490: /* check if the fixed size part of the packet is in buffer. */
! 1491: if (have < 3)
! 1492: return;
! 1493: /* try to guess the protocol */
! 1494: p = sshbuf_ptr(c->output);
! 1495: switch (p[0]) {
! 1496: case 0x04:
! 1497: /* switch input/output for reverse forwarding */
! 1498: ret = channel_decode_socks4(c, c->output, c->input);
! 1499: break;
! 1500: case 0x05:
! 1501: ret = channel_decode_socks5(c, c->output, c->input);
! 1502: break;
! 1503: default:
! 1504: ret = -1;
! 1505: break;
! 1506: }
! 1507: if (ret < 0) {
! 1508: rdynamic_close(ssh, c);
! 1509: } else if (ret == 0) {
! 1510: debug2("channel %d: pre_rdynamic: need more", c->self);
! 1511: /* send socks request to peer */
! 1512: len = sshbuf_len(c->input);
! 1513: if (len > 0 && len < c->remote_window) {
! 1514: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
! 1515: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
! 1516: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
! 1517: (r = sshpkt_send(ssh)) != 0) {
! 1518: fatal("%s: channel %i: rdynamic: %s", __func__,
! 1519: c->self, ssh_err(r));
! 1520: }
! 1521: if ((r = sshbuf_consume(c->input, len)) != 0) {
! 1522: fatal("%s: channel %d: consume: %s",
! 1523: __func__, c->self, ssh_err(r));
! 1524: }
! 1525: c->remote_window -= len;
! 1526: }
! 1527: } else if (rdynamic_connect_finish(ssh, c) < 0) {
! 1528: /* the connect failed */
! 1529: rdynamic_close(ssh, c);
! 1530: }
! 1531: }
! 1532:
1.41 markus 1533: /* This is our fake X11 server socket. */
1.127 itojun 1534: static void
1.367 djm 1535: channel_post_x11_listener(struct ssh *ssh, Channel *c,
1536: fd_set *readset, fd_set *writeset)
1.41 markus 1537: {
1.113 markus 1538: Channel *nc;
1.285 djm 1539: struct sockaddr_storage addr;
1.367 djm 1540: int r, newsock, oerrno, remote_port;
1.41 markus 1541: socklen_t addrlen;
1.85 markus 1542: char buf[16384], *remote_ipaddr;
1.25 markus 1543:
1.367 djm 1544: if (!FD_ISSET(c->sock, readset))
1545: return;
1546:
1547: debug("X11 connection requested.");
1548: addrlen = sizeof(addr);
1549: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1550: if (c->single_connection) {
1551: oerrno = errno;
1552: debug2("single_connection: closing X11 listener.");
1553: channel_close_fd(ssh, &c->sock);
1554: chan_mark_dead(ssh, c);
1555: errno = oerrno;
1556: }
1557: if (newsock < 0) {
1558: if (errno != EINTR && errno != EWOULDBLOCK &&
1559: errno != ECONNABORTED)
1560: error("accept: %.100s", strerror(errno));
1561: if (errno == EMFILE || errno == ENFILE)
1562: c->notbefore = monotime() + 1;
1563: return;
1564: }
1565: set_nodelay(newsock);
1566: remote_ipaddr = get_peer_ipaddr(newsock);
1567: remote_port = get_peer_port(newsock);
1568: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1569: remote_ipaddr, remote_port);
1570:
1571: nc = channel_new(ssh, "accepted x11 socket",
1572: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1573: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1574: open_preamble(ssh, __func__, nc, "x11");
1575: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0) {
1576: fatal("%s: channel %i: reply %s", __func__,
1577: c->self, ssh_err(r));
1578: }
1579: if ((datafellows & SSH_BUG_X11FWD) != 0)
1580: debug2("channel %d: ssh2 x11 bug compat mode", nc->self);
1581: else if ((r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1582: fatal("%s: channel %i: reply %s", __func__,
1583: c->self, ssh_err(r));
1.41 markus 1584: }
1.367 djm 1585: if ((r = sshpkt_send(ssh)) != 0)
1586: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1587: free(remote_ipaddr);
1.41 markus 1588: }
1.25 markus 1589:
1.127 itojun 1590: static void
1.367 djm 1591: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1592: {
1.328 djm 1593: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1594: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1595: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1596: int remote_port = get_peer_port(c->sock);
1.367 djm 1597: int r;
1.303 djm 1598:
1599: if (remote_port == -1) {
1600: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1601: free(remote_ipaddr);
1.303 djm 1602: remote_ipaddr = xstrdup("127.0.0.1");
1603: remote_port = 65535;
1604: }
1.103 markus 1605:
1.367 djm 1606: free(c->remote_name);
1607: xasprintf(&c->remote_name,
1.103 markus 1608: "%s: listening port %d for %.100s port %d, "
1.328 djm 1609: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1610: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1611: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1612:
1.367 djm 1613: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1614: if (strcmp(rtype, "direct-tcpip") == 0) {
1615: /* target host, port */
1.367 djm 1616: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1617: (r = sshpkt_put_u32(ssh, c->host_port)) != 0) {
1618: fatal("%s: channel %i: reply %s", __func__,
1619: c->self, ssh_err(r));
1620: }
1.358 djm 1621: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1622: /* target path */
1.367 djm 1623: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1624: fatal("%s: channel %i: reply %s", __func__,
1625: c->self, ssh_err(r));
1626: }
1.358 djm 1627: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1628: /* listen path */
1.367 djm 1629: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1630: fatal("%s: channel %i: reply %s", __func__,
1631: c->self, ssh_err(r));
1632: }
1.103 markus 1633: } else {
1.358 djm 1634: /* listen address, port */
1.367 djm 1635: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1636: (r = sshpkt_put_u32(ssh, local_port)) != 0) {
1637: fatal("%s: channel %i: reply %s", __func__,
1638: c->self, ssh_err(r));
1639: }
1.358 djm 1640: }
1641: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1642: /* reserved for future owner/mode info */
1.367 djm 1643: if ((r = sshpkt_put_cstring(ssh, "")) != 0) {
1644: fatal("%s: channel %i: reply %s", __func__,
1645: c->self, ssh_err(r));
1646: }
1.358 djm 1647: } else {
1648: /* originator host and port */
1.367 djm 1649: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1650: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0) {
1651: fatal("%s: channel %i: reply %s", __func__,
1652: c->self, ssh_err(r));
1653: }
1.103 markus 1654: }
1.367 djm 1655: if ((r = sshpkt_send(ssh)) != 0)
1656: fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1.321 djm 1657: free(remote_ipaddr);
1.328 djm 1658: free(local_ipaddr);
1.103 markus 1659: }
1660:
1.226 djm 1661: static void
1662: channel_set_reuseaddr(int fd)
1663: {
1664: int on = 1;
1665:
1666: /*
1667: * Set socket options.
1668: * Allow local port reuse in TIME_WAIT.
1669: */
1670: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1671: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1.347 djm 1672: }
1673:
1674: void
1.367 djm 1675: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1676: {
1.367 djm 1677: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1678: }
1679:
1.41 markus 1680: /*
1681: * This socket is listening for connections to a forwarded TCP/IP port.
1682: */
1.127 itojun 1683: static void
1.367 djm 1684: channel_post_port_listener(struct ssh *ssh, Channel *c,
1685: fd_set *readset, fd_set *writeset)
1.41 markus 1686: {
1.103 markus 1687: Channel *nc;
1.285 djm 1688: struct sockaddr_storage addr;
1.113 markus 1689: int newsock, nextstate;
1.41 markus 1690: socklen_t addrlen;
1.103 markus 1691: char *rtype;
1.73 markus 1692:
1.367 djm 1693: if (!FD_ISSET(c->sock, readset))
1694: return;
1695:
1696: debug("Connection to port %d forwarding to %.100s port %d requested.",
1697: c->listening_port, c->path, c->host_port);
1.103 markus 1698:
1.367 djm 1699: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1700: nextstate = SSH_CHANNEL_OPENING;
1701: rtype = "forwarded-tcpip";
1702: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1703: nextstate = SSH_CHANNEL_OPENING;
1704: rtype = "forwarded-streamlocal@openssh.com";
1705: } else if (c->host_port == PORT_STREAMLOCAL) {
1706: nextstate = SSH_CHANNEL_OPENING;
1707: rtype = "direct-streamlocal@openssh.com";
1708: } else if (c->host_port == 0) {
1709: nextstate = SSH_CHANNEL_DYNAMIC;
1710: rtype = "dynamic-tcpip";
1711: } else {
1712: nextstate = SSH_CHANNEL_OPENING;
1713: rtype = "direct-tcpip";
1714: }
1.103 markus 1715:
1.367 djm 1716: addrlen = sizeof(addr);
1717: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1718: if (newsock < 0) {
1719: if (errno != EINTR && errno != EWOULDBLOCK &&
1720: errno != ECONNABORTED)
1721: error("accept: %.100s", strerror(errno));
1722: if (errno == EMFILE || errno == ENFILE)
1723: c->notbefore = monotime() + 1;
1724: return;
1.41 markus 1725: }
1.367 djm 1726: if (c->host_port != PORT_STREAMLOCAL)
1727: set_nodelay(newsock);
1728: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1729: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1730: nc->listening_port = c->listening_port;
1731: nc->host_port = c->host_port;
1732: if (c->path != NULL)
1733: nc->path = xstrdup(c->path);
1734:
1735: if (nextstate != SSH_CHANNEL_DYNAMIC)
1736: port_open_helper(ssh, nc, rtype);
1.41 markus 1737: }
1.25 markus 1738:
1.41 markus 1739: /*
1740: * This is the authentication agent socket listening for connections from
1741: * clients.
1742: */
1.127 itojun 1743: static void
1.367 djm 1744: channel_post_auth_listener(struct ssh *ssh, Channel *c,
1745: fd_set *readset, fd_set *writeset)
1.41 markus 1746: {
1.113 markus 1747: Channel *nc;
1.367 djm 1748: int r, newsock;
1.285 djm 1749: struct sockaddr_storage addr;
1.41 markus 1750: socklen_t addrlen;
1.25 markus 1751:
1.367 djm 1752: if (!FD_ISSET(c->sock, readset))
1753: return;
1754:
1755: addrlen = sizeof(addr);
1756: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1757: if (newsock < 0) {
1758: error("accept from auth socket: %.100s", strerror(errno));
1759: if (errno == EMFILE || errno == ENFILE)
1760: c->notbefore = monotime() + 1;
1761: return;
1.41 markus 1762: }
1.367 djm 1763: nc = channel_new(ssh, "accepted auth socket",
1764: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1765: c->local_window_max, c->local_maxpacket,
1766: 0, "accepted auth socket", 1);
1767: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1768: if ((r = sshpkt_send(ssh)) != 0)
1769: fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
1.41 markus 1770: }
1.25 markus 1771:
1.127 itojun 1772: static void
1.367 djm 1773: channel_post_connecting(struct ssh *ssh, Channel *c,
1774: fd_set *readset, fd_set *writeset)
1.75 markus 1775: {
1.372 ! markus 1776: int err = 0, sock, isopen, r;
1.129 stevesk 1777: socklen_t sz = sizeof(err);
1.114 markus 1778:
1.367 djm 1779: if (!FD_ISSET(c->sock, writeset))
1780: return;
1.368 djm 1781: if (!c->have_remote_id)
1782: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.372 ! markus 1783: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
! 1784: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.367 djm 1785: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1786: err = errno;
1787: error("getsockopt SO_ERROR failed");
1788: }
1789: if (err == 0) {
1790: debug("channel %d: connected to %s port %d",
1791: c->self, c->connect_ctx.host, c->connect_ctx.port);
1792: channel_connect_ctx_free(&c->connect_ctx);
1793: c->type = SSH_CHANNEL_OPEN;
1.372 ! markus 1794: if (isopen) {
! 1795: /* no message necessary */
! 1796: } else {
! 1797: if ((r = sshpkt_start(ssh,
! 1798: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
! 1799: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
! 1800: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
! 1801: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
! 1802: (r = sshpkt_put_u32(ssh, c->local_maxpacket))
! 1803: != 0)
! 1804: fatal("%s: channel %i: confirm: %s", __func__,
! 1805: c->self, ssh_err(r));
! 1806: if ((r = sshpkt_send(ssh)) != 0)
! 1807: fatal("%s: channel %i: %s", __func__, c->self,
! 1808: ssh_err(r));
1.367 djm 1809: }
1810: } else {
1811: debug("channel %d: connection failed: %s",
1812: c->self, strerror(err));
1813: /* Try next address, if any */
1814: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1815: close(c->sock);
1816: c->sock = c->rfd = c->wfd = sock;
1817: channel_find_maxfd(ssh->chanctxt);
1818: return;
1819: }
1820: /* Exhausted all addresses */
1821: error("connect_to %.100s port %d: failed.",
1822: c->connect_ctx.host, c->connect_ctx.port);
1823: channel_connect_ctx_free(&c->connect_ctx);
1.372 ! markus 1824: if (isopen) {
! 1825: rdynamic_close(ssh, c);
! 1826: } else {
! 1827: if ((r = sshpkt_start(ssh,
! 1828: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
! 1829: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
! 1830: (r = sshpkt_put_u32(ssh, SSH2_OPEN_CONNECT_FAILED))
! 1831: != 0)
! 1832: fatal("%s: channel %i: failure: %s", __func__,
! 1833: c->self, ssh_err(r));
! 1834: if ((datafellows & SSH_BUG_OPENFAILURE) == 0 &&
! 1835: ((r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
! 1836: (r = sshpkt_put_cstring(ssh, "")) != 0))
! 1837: fatal("%s: channel %i: failure: %s", __func__,
! 1838: c->self, ssh_err(r));
! 1839: if ((r = sshpkt_send(ssh)) != 0)
! 1840: fatal("%s: channel %i: %s", __func__, c->self,
! 1841: ssh_err(r));
! 1842: chan_mark_dead(ssh, c);
1.75 markus 1843: }
1844: }
1845: }
1846:
1.127 itojun 1847: static int
1.367 djm 1848: channel_handle_rfd(struct ssh *ssh, Channel *c,
1849: fd_set *readset, fd_set *writeset)
1.41 markus 1850: {
1.214 markus 1851: char buf[CHAN_RBUF];
1.367 djm 1852: ssize_t len;
1853: int r;
1.25 markus 1854:
1.367 djm 1855: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
1856: return 1;
1857:
1858: len = read(c->rfd, buf, sizeof(buf));
1859: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1860: return 1;
1861: if (len <= 0) {
1862: debug2("channel %d: read<=0 rfd %d len %zd",
1863: c->self, c->rfd, len);
1864: if (c->type != SSH_CHANNEL_OPEN) {
1865: debug2("channel %d: not open", c->self);
1866: chan_mark_dead(ssh, c);
1.41 markus 1867: return -1;
1.65 markus 1868: } else {
1.367 djm 1869: chan_read_failed(ssh, c);
1.65 markus 1870: }
1.367 djm 1871: return -1;
1872: }
1873: if (c->input_filter != NULL) {
1874: if (c->input_filter(ssh, c, buf, len) == -1) {
1875: debug2("channel %d: filter stops", c->self);
1876: chan_read_failed(ssh, c);
1877: }
1878: } else if (c->datagram) {
1879: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1880: fatal("%s: channel %d: put datagram: %s", __func__,
1881: c->self, ssh_err(r));
1882: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
1883: fatal("%s: channel %d: put data: %s", __func__,
1884: c->self, ssh_err(r));
1.41 markus 1885: }
1886: return 1;
1887: }
1.241 deraadt 1888:
1.127 itojun 1889: static int
1.367 djm 1890: channel_handle_wfd(struct ssh *ssh, Channel *c,
1891: fd_set *readset, fd_set *writeset)
1.41 markus 1892: {
1.95 markus 1893: struct termios tio;
1.367 djm 1894: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1895: size_t dlen, olen = 0;
1896: int r, len;
1897:
1898: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
1899: sshbuf_len(c->output) == 0)
1900: return 1;
1.25 markus 1901:
1.41 markus 1902: /* Send buffered output data to the socket. */
1.367 djm 1903: olen = sshbuf_len(c->output);
1904: if (c->output_filter != NULL) {
1905: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1906: debug2("channel %d: filter stops", c->self);
1907: if (c->type != SSH_CHANNEL_OPEN)
1908: chan_mark_dead(ssh, c);
1909: else
1910: chan_write_failed(ssh, c);
1911: return -1;
1.231 reyk 1912: }
1.367 djm 1913: } else if (c->datagram) {
1914: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1915: fatal("%s: channel %d: get datagram: %s", __func__,
1916: c->self, ssh_err(r));
1.369 djm 1917: buf = data;
1.367 djm 1918: } else {
1919: buf = data = sshbuf_mutable_ptr(c->output);
1920: dlen = sshbuf_len(c->output);
1921: }
1.231 reyk 1922:
1.367 djm 1923: if (c->datagram) {
1924: /* ignore truncated writes, datagrams might get lost */
1925: len = write(c->wfd, data, dlen);
1926: free(data);
1.53 markus 1927: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1928: return 1;
1.367 djm 1929: if (len <= 0)
1930: goto write_fail;
1931: goto out;
1932: }
1933:
1934: len = write(c->wfd, buf, dlen);
1935: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1936: return 1;
1937: if (len <= 0) {
1938: write_fail:
1939: if (c->type != SSH_CHANNEL_OPEN) {
1940: debug2("channel %d: not open", c->self);
1941: chan_mark_dead(ssh, c);
1.41 markus 1942: return -1;
1.367 djm 1943: } else {
1944: chan_write_failed(ssh, c);
1.91 markus 1945: }
1.367 djm 1946: return -1;
1947: }
1948: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
1949: if (tcgetattr(c->wfd, &tio) == 0 &&
1950: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1951: /*
1952: * Simulate echo to reduce the impact of
1953: * traffic analysis. We need to match the
1954: * size of a SSH2_MSG_CHANNEL_DATA message
1955: * (4 byte channel id + buf)
1956: */
1957: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
1958: (r = sshpkt_send(ssh)) != 0)
1959: fatal("%s: channel %d: ignore: %s",
1960: __func__, c->self, ssh_err(r));
1.25 markus 1961: }
1.367 djm 1962: }
1963: if ((r = sshbuf_consume(c->output, len)) != 0) {
1964: fatal("%s: channel %d: consume: %s",
1965: __func__, c->self, ssh_err(r));
1.44 markus 1966: }
1.309 djm 1967: out:
1.367 djm 1968: c->local_consumed += olen - sshbuf_len(c->output);
1969:
1970: return 1;
1971: }
1972:
1973: static int
1974: channel_handle_efd_write(struct ssh *ssh, Channel *c,
1975: fd_set *readset, fd_set *writeset)
1976: {
1977: int r;
1978: ssize_t len;
1979:
1980: if (!FD_ISSET(c->efd, writeset) || sshbuf_len(c->extended) == 0)
1981: return 1;
1982:
1983: len = write(c->efd, sshbuf_ptr(c->extended),
1984: sshbuf_len(c->extended));
1985: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1986: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1987: return 1;
1988: if (len <= 0) {
1989: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1990: channel_close_fd(ssh, &c->efd);
1991: } else {
1992: if ((r = sshbuf_consume(c->extended, len)) != 0) {
1993: fatal("%s: channel %d: consume: %s",
1994: __func__, c->self, ssh_err(r));
1995: }
1996: c->local_consumed += len;
1997: }
1.44 markus 1998: return 1;
1999: }
1.241 deraadt 2000:
1.127 itojun 2001: static int
1.367 djm 2002: channel_handle_efd_read(struct ssh *ssh, Channel *c,
2003: fd_set *readset, fd_set *writeset)
1.44 markus 2004: {
1.214 markus 2005: char buf[CHAN_RBUF];
1.367 djm 2006: int r;
2007: ssize_t len;
2008:
2009: if (!FD_ISSET(c->efd, readset))
2010: return 1;
1.44 markus 2011:
1.367 djm 2012: len = read(c->efd, buf, sizeof(buf));
2013: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
2014: if (len < 0 && (errno == EINTR || errno == EAGAIN))
2015: return 1;
2016: if (len <= 0) {
2017: debug2("channel %d: closing read-efd %d",
2018: c->self, c->efd);
2019: channel_close_fd(ssh, &c->efd);
2020: } else {
2021: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
2022: debug3("channel %d: discard efd",
2023: c->self);
2024: } else if ((r = sshbuf_put(c->extended, buf, len)) != 0) {
2025: fatal("%s: channel %d: append: %s",
2026: __func__, c->self, ssh_err(r));
1.44 markus 2027: }
2028: }
2029: return 1;
2030: }
1.241 deraadt 2031:
1.127 itojun 2032: static int
1.367 djm 2033: channel_handle_efd(struct ssh *ssh, Channel *c,
2034: fd_set *readset, fd_set *writeset)
1.44 markus 2035: {
1.367 djm 2036: if (c->efd == -1)
2037: return 1;
2038:
2039: /** XXX handle drain efd, too */
2040:
2041: if (c->extended_usage == CHAN_EXTENDED_WRITE)
2042: return channel_handle_efd_write(ssh, c, readset, writeset);
2043: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2044: c->extended_usage == CHAN_EXTENDED_IGNORE)
2045: return channel_handle_efd_read(ssh, c, readset, writeset);
2046:
2047: return 1;
2048: }
2049:
2050: static int
2051: channel_check_window(struct ssh *ssh, Channel *c)
2052: {
2053: int r;
2054:
1.104 markus 2055: if (c->type == SSH_CHANNEL_OPEN &&
2056: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2057: ((c->local_window_max - c->local_window >
1.269 markus 2058: c->local_maxpacket*3) ||
2059: c->local_window < c->local_window_max/2) &&
1.44 markus 2060: c->local_consumed > 0) {
1.368 djm 2061: if (!c->have_remote_id)
2062: fatal(":%s: channel %d: no remote id",
2063: __func__, c->self);
1.367 djm 2064: if ((r = sshpkt_start(ssh,
2065: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2066: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2067: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2068: (r = sshpkt_send(ssh)) != 0) {
2069: fatal("%s: channel %i: %s", __func__,
2070: c->self, ssh_err(r));
2071: }
1.70 markus 2072: debug2("channel %d: window %d sent adjust %d",
1.44 markus 2073: c->self, c->local_window,
2074: c->local_consumed);
2075: c->local_window += c->local_consumed;
2076: c->local_consumed = 0;
1.1 deraadt 2077: }
1.41 markus 2078: return 1;
1.1 deraadt 2079: }
2080:
1.127 itojun 2081: static void
1.367 djm 2082: channel_post_open(struct ssh *ssh, Channel *c,
2083: fd_set *readset, fd_set *writeset)
1.41 markus 2084: {
1.367 djm 2085: channel_handle_rfd(ssh, c, readset, writeset);
2086: channel_handle_wfd(ssh, c, readset, writeset);
2087: channel_handle_efd(ssh, c, readset, writeset);
2088: channel_check_window(ssh, c);
1.44 markus 2089: }
2090:
1.302 djm 2091: static u_int
1.367 djm 2092: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2093: {
2094: char buf[CHAN_RBUF];
1.367 djm 2095: ssize_t len;
1.302 djm 2096: u_int rlen;
1.367 djm 2097: int r;
1.302 djm 2098:
1.367 djm 2099: if (sshbuf_len(c->input) < need) {
2100: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2101: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.349 naddy 2102: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2103: return sshbuf_len(c->input);
1.302 djm 2104: if (len <= 0) {
1.367 djm 2105: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2106: c->self, c->rfd, len);
1.367 djm 2107: chan_read_failed(ssh, c);
1.349 naddy 2108: return 0;
1.367 djm 2109: } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
2110: fatal("%s: channel %d: append: %s",
2111: __func__, c->self, ssh_err(r));
2112: }
1.302 djm 2113: }
1.367 djm 2114: return sshbuf_len(c->input);
1.302 djm 2115: }
2116:
2117: static void
1.367 djm 2118: channel_post_mux_client_read(struct ssh *ssh, Channel *c,
2119: fd_set *readset, fd_set *writeset)
1.302 djm 2120: {
2121: u_int need;
2122:
1.367 djm 2123: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
2124: return;
2125: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2126: return;
2127: if (c->mux_pause)
2128: return;
2129:
2130: /*
2131: * Don't not read past the precise end of packets to
2132: * avoid disrupting fd passing.
2133: */
2134: if (read_mux(ssh, c, 4) < 4) /* read header */
2135: return;
2136: /* XXX sshbuf_peek_u32 */
2137: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2138: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2139: if (need > CHANNEL_MUX_MAX_PACKET) {
2140: debug2("channel %d: packet too big %u > %u",
2141: c->self, CHANNEL_MUX_MAX_PACKET, need);
2142: chan_rcvd_oclose(ssh, c);
2143: return;
2144: }
2145: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2146: return;
2147: if (c->mux_rcb(ssh, c) != 0) {
2148: debug("channel %d: mux_rcb failed", c->self);
2149: chan_mark_dead(ssh, c);
2150: return;
1.302 djm 2151: }
1.367 djm 2152: }
2153:
2154: static void
2155: channel_post_mux_client_write(struct ssh *ssh, Channel *c,
2156: fd_set *readset, fd_set *writeset)
2157: {
2158: ssize_t len;
2159: int r;
1.302 djm 2160:
1.367 djm 2161: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
2162: sshbuf_len(c->output) == 0)
2163: return;
2164:
2165: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
2166: if (len < 0 && (errno == EINTR || errno == EAGAIN))
2167: return;
2168: if (len <= 0) {
2169: chan_mark_dead(ssh, c);
2170: return;
1.302 djm 2171: }
1.367 djm 2172: if ((r = sshbuf_consume(c->output, len)) != 0)
2173: fatal("%s: channel %d: consume: %s", __func__,
2174: c->self, ssh_err(r));
2175: }
2176:
2177: static void
2178: channel_post_mux_client(struct ssh *ssh, Channel *c,
2179: fd_set *readset, fd_set *writeset)
2180: {
2181: channel_post_mux_client_read(ssh, c, readset, writeset);
2182: channel_post_mux_client_write(ssh, c, readset, writeset);
1.302 djm 2183: }
2184:
2185: static void
1.367 djm 2186: channel_post_mux_listener(struct ssh *ssh, Channel *c,
2187: fd_set *readset, fd_set *writeset)
1.302 djm 2188: {
2189: Channel *nc;
2190: struct sockaddr_storage addr;
2191: socklen_t addrlen;
2192: int newsock;
2193: uid_t euid;
2194: gid_t egid;
2195:
2196: if (!FD_ISSET(c->sock, readset))
2197: return;
2198:
2199: debug("multiplexing control connection");
2200:
2201: /*
2202: * Accept connection on control socket
2203: */
2204: memset(&addr, 0, sizeof(addr));
2205: addrlen = sizeof(addr);
2206: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2207: &addrlen)) == -1) {
2208: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 2209: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2210: c->notbefore = monotime() + 1;
1.302 djm 2211: return;
2212: }
2213:
2214: if (getpeereid(newsock, &euid, &egid) < 0) {
2215: error("%s getpeereid failed: %s", __func__,
2216: strerror(errno));
2217: close(newsock);
2218: return;
2219: }
2220: if ((euid != 0) && (getuid() != euid)) {
2221: error("multiplex uid mismatch: peer euid %u != uid %u",
2222: (u_int)euid, (u_int)getuid());
2223: close(newsock);
2224: return;
2225: }
1.367 djm 2226: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2227: newsock, newsock, -1, c->local_window_max,
2228: c->local_maxpacket, 0, "mux-control", 1);
2229: nc->mux_rcb = c->mux_rcb;
1.367 djm 2230: debug3("%s: new mux channel %d fd %d", __func__, nc->self, nc->sock);
1.302 djm 2231: /* establish state */
1.367 djm 2232: nc->mux_rcb(ssh, nc);
1.302 djm 2233: /* mux state transitions must not elicit protocol messages */
2234: nc->flags |= CHAN_LOCAL;
2235: }
2236:
1.127 itojun 2237: static void
1.367 djm 2238: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2239: {
1.367 djm 2240: chan_fn **pre, **post;
2241:
2242: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
2243: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
2244: fatal("%s: allocation failed", __func__);
2245:
2246: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2247: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2248: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2249: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2250: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2251: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2252: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2253: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2254: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2255: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 ! markus 2256: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2257: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2258: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2259:
2260: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2261: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2262: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2263: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2264: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2265: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2266: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2267: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2268: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 ! markus 2269: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2270: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2271: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2272:
1.367 djm 2273: sc->channel_pre = pre;
2274: sc->channel_post = post;
1.44 markus 2275: }
2276:
1.140 markus 2277: /* gc dead channels */
2278: static void
1.367 djm 2279: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2280: {
2281: if (c == NULL)
2282: return;
2283: if (c->detach_user != NULL) {
1.367 djm 2284: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2285: return;
1.194 markus 2286: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2287: c->detach_user(ssh, c->self, NULL);
1.140 markus 2288: /* if we still have a callback */
2289: if (c->detach_user != NULL)
2290: return;
1.194 markus 2291: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2292: }
1.367 djm 2293: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2294: return;
1.194 markus 2295: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2296: channel_free(ssh, c);
1.140 markus 2297: }
2298:
1.367 djm 2299: enum channel_table { CHAN_PRE, CHAN_POST };
2300:
1.127 itojun 2301: static void
1.367 djm 2302: channel_handler(struct ssh *ssh, int table,
1.366 djm 2303: fd_set *readset, fd_set *writeset, time_t *unpause_secs)
1.41 markus 2304: {
1.367 djm 2305: struct ssh_channels *sc = ssh->chanctxt;
2306: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2307: u_int i, oalloc;
1.41 markus 2308: Channel *c;
1.317 djm 2309: time_t now;
1.25 markus 2310:
1.322 dtucker 2311: now = monotime();
1.317 djm 2312: if (unpause_secs != NULL)
2313: *unpause_secs = 0;
1.367 djm 2314: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2315: c = sc->channels[i];
1.113 markus 2316: if (c == NULL)
1.41 markus 2317: continue;
1.299 markus 2318: if (c->delayed) {
1.367 djm 2319: if (table == CHAN_PRE)
1.299 markus 2320: c->delayed = 0;
2321: else
2322: continue;
2323: }
1.317 djm 2324: if (ftab[c->type] != NULL) {
2325: /*
2326: * Run handlers that are not paused.
2327: */
2328: if (c->notbefore <= now)
1.367 djm 2329: (*ftab[c->type])(ssh, c, readset, writeset);
1.317 djm 2330: else if (unpause_secs != NULL) {
2331: /*
2332: * Collect the time that the earliest
2333: * channel comes off pause.
2334: */
2335: debug3("%s: chan %d: skip for %d more seconds",
2336: __func__, c->self,
2337: (int)(c->notbefore - now));
2338: if (*unpause_secs == 0 ||
2339: (c->notbefore - now) < *unpause_secs)
2340: *unpause_secs = c->notbefore - now;
2341: }
2342: }
1.367 djm 2343: channel_garbage_collect(ssh, c);
1.1 deraadt 2344: }
1.317 djm 2345: if (unpause_secs != NULL && *unpause_secs != 0)
2346: debug3("%s: first channel unpauses in %d seconds",
2347: __func__, (int)*unpause_secs);
1.1 deraadt 2348: }
2349:
1.121 markus 2350: /*
1.372 ! markus 2351: * Create sockets before allocating the select bitmasks.
! 2352: * This is necessary for things that need to happen after reading
! 2353: * the network-input but before channel_prepare_select().
! 2354: */
! 2355: static void
! 2356: channel_before_prepare_select(struct ssh *ssh)
! 2357: {
! 2358: struct ssh_channels *sc = ssh->chanctxt;
! 2359: Channel *c;
! 2360: u_int i, oalloc;
! 2361:
! 2362: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
! 2363: c = sc->channels[i];
! 2364: if (c == NULL)
! 2365: continue;
! 2366: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
! 2367: channel_before_prepare_select_rdynamic(ssh, c);
! 2368: }
! 2369: }
! 2370:
! 2371: /*
1.121 markus 2372: * Allocate/update select bitmasks and add any bits relevant to channels in
2373: * select bitmasks.
2374: */
1.49 markus 2375: void
1.366 djm 2376: channel_prepare_select(struct ssh *ssh, fd_set **readsetp, fd_set **writesetp,
2377: int *maxfdp, u_int *nallocp, time_t *minwait_secs)
1.41 markus 2378: {
1.243 djm 2379: u_int n, sz, nfdset;
1.84 markus 2380:
1.372 ! markus 2381: channel_before_prepare_select(ssh); /* might update channel_max_fd */
! 2382:
1.367 djm 2383: n = MAXIMUM(*maxfdp, ssh->chanctxt->channel_max_fd);
1.84 markus 2384:
1.243 djm 2385: nfdset = howmany(n+1, NFDBITS);
2386: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2387: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2388: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2389: sz = nfdset * sizeof(fd_mask);
2390:
1.132 markus 2391: /* perhaps check sz < nalloc/2 and shrink? */
2392: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2393: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2394: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2395: *nallocp = sz;
1.84 markus 2396: }
1.132 markus 2397: *maxfdp = n;
1.84 markus 2398: memset(*readsetp, 0, sz);
2399: memset(*writesetp, 0, sz);
2400:
1.366 djm 2401: if (!ssh_packet_is_rekeying(ssh))
1.367 djm 2402: channel_handler(ssh, CHAN_PRE, *readsetp, *writesetp,
1.317 djm 2403: minwait_secs);
1.41 markus 2404: }
2405:
1.121 markus 2406: /*
2407: * After select, perform any appropriate operations for channels which have
2408: * events pending.
2409: */
1.49 markus 2410: void
1.366 djm 2411: channel_after_select(struct ssh *ssh, fd_set *readset, fd_set *writeset)
1.41 markus 2412: {
1.367 djm 2413: channel_handler(ssh, CHAN_POST, readset, writeset, NULL);
2414: }
2415:
2416: /*
2417: * Enqueue data for channels with open or draining c->input.
2418: */
2419: static void
2420: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2421: {
2422: size_t len, dlen;
2423: int r;
2424:
2425: if ((len = sshbuf_len(c->input)) == 0) {
2426: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2427: /*
2428: * input-buffer is empty and read-socket shutdown:
2429: * tell peer, that we will not send more data:
2430: * send IEOF.
2431: * hack for extended data: delay EOF if EFD still
2432: * in use.
2433: */
2434: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2435: debug2("channel %d: "
2436: "ibuf_empty delayed efd %d/(%zu)",
2437: c->self, c->efd, sshbuf_len(c->extended));
2438: else
2439: chan_ibuf_empty(ssh, c);
2440: }
2441: return;
2442: }
2443:
1.368 djm 2444: if (!c->have_remote_id)
2445: fatal(":%s: channel %d: no remote id", __func__, c->self);
2446:
1.367 djm 2447: if (c->datagram) {
2448: /* Check datagram will fit; drop if not */
2449: if ((r = sshbuf_peek_string_direct(c->input, NULL, &dlen)) != 0)
2450: fatal("%s: channel %d: peek datagram: %s", __func__,
2451: c->self, ssh_err(r));
2452: /*
2453: * XXX this does tail-drop on the datagram queue which is
2454: * usually suboptimal compared to head-drop. Better to have
2455: * backpressure at read time? (i.e. read + discard)
2456: */
2457: if (dlen > c->remote_window || dlen > c->remote_maxpacket) {
2458: debug("channel %d: datagram too big", c->self);
2459: return;
2460: }
2461: /* Enqueue it */
2462: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2463: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2464: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
2465: (r = sshpkt_send(ssh)) != 0) {
2466: fatal("%s: channel %i: datagram: %s", __func__,
2467: c->self, ssh_err(r));
2468: }
2469: c->remote_window -= dlen;
2470: return;
2471: }
2472:
2473: /* Enqueue packet for buffered data. */
2474: if (len > c->remote_window)
2475: len = c->remote_window;
2476: if (len > c->remote_maxpacket)
2477: len = c->remote_maxpacket;
2478: if (len == 0)
2479: return;
2480: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2481: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2482: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
2483: (r = sshpkt_send(ssh)) != 0) {
2484: fatal("%s: channel %i: data: %s", __func__,
2485: c->self, ssh_err(r));
2486: }
2487: if ((r = sshbuf_consume(c->input, len)) != 0)
2488: fatal("%s: channel %i: consume: %s", __func__,
2489: c->self, ssh_err(r));
2490: c->remote_window -= len;
1.41 markus 2491: }
2492:
1.367 djm 2493: /*
2494: * Enqueue data for channels with open c->extended in read mode.
2495: */
2496: static void
2497: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2498: {
2499: size_t len;
2500: int r;
2501:
2502: if ((len = sshbuf_len(c->extended)) == 0)
2503: return;
2504:
2505: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2506: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2507: if (len > c->remote_window)
2508: len = c->remote_window;
2509: if (len > c->remote_maxpacket)
2510: len = c->remote_maxpacket;
2511: if (len == 0)
2512: return;
1.368 djm 2513: if (!c->have_remote_id)
2514: fatal(":%s: channel %d: no remote id", __func__, c->self);
1.367 djm 2515: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2516: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2517: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2518: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
2519: (r = sshpkt_send(ssh)) != 0) {
2520: fatal("%s: channel %i: data: %s", __func__,
2521: c->self, ssh_err(r));
2522: }
2523: if ((r = sshbuf_consume(c->extended, len)) != 0)
2524: fatal("%s: channel %i: consume: %s", __func__,
2525: c->self, ssh_err(r));
2526: c->remote_window -= len;
2527: debug2("channel %d: sent ext data %zu", c->self, len);
2528: }
1.121 markus 2529:
1.84 markus 2530: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2531: void
1.367 djm 2532: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2533: {
1.367 djm 2534: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2535: Channel *c;
1.367 djm 2536: u_int i;
1.1 deraadt 2537:
1.367 djm 2538: for (i = 0; i < sc->channels_alloc; i++) {
2539: c = sc->channels[i];
1.113 markus 2540: if (c == NULL)
2541: continue;
1.37 markus 2542:
1.121 markus 2543: /*
2544: * We are only interested in channels that can have buffered
2545: * incoming data.
2546: */
1.358 djm 2547: if (c->type != SSH_CHANNEL_OPEN)
2548: continue;
2549: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2550: /* XXX is this true? */
1.367 djm 2551: debug3("channel %d: will not send data after close",
2552: c->self);
1.44 markus 2553: continue;
2554: }
1.25 markus 2555:
2556: /* Get the amount of buffered data for this channel. */
1.367 djm 2557: if (c->istate == CHAN_INPUT_OPEN ||
2558: c->istate == CHAN_INPUT_WAIT_DRAIN)
2559: channel_output_poll_input_open(ssh, c);
1.44 markus 2560: /* Send extended data, i.e. stderr */
1.358 djm 2561: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2562: c->extended_usage == CHAN_EXTENDED_READ)
2563: channel_output_poll_extended_read(ssh, c);
1.25 markus 2564: }
1.1 deraadt 2565: }
2566:
1.354 markus 2567: /* -- mux proxy support */
2568:
2569: /*
2570: * When multiplexing channel messages for mux clients we have to deal
2571: * with downstream messages from the mux client and upstream messages
2572: * from the ssh server:
2573: * 1) Handling downstream messages is straightforward and happens
2574: * in channel_proxy_downstream():
2575: * - We forward all messages (mostly) unmodified to the server.
2576: * - However, in order to route messages from upstream to the correct
2577: * downstream client, we have to replace the channel IDs used by the
2578: * mux clients with a unique channel ID because the mux clients might
2579: * use conflicting channel IDs.
2580: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2581: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2582: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2583: * with the newly allocated channel ID.
2584: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
2585: * channels and procesed by channel_proxy_upstream(). The local channel ID
2586: * is then translated back to the original mux client ID.
2587: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2588: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2589: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2590: * downstream mux client are removed.
2591: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2592: * requires more work, because they are not addressed to a specific
2593: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2594: * out whether the request is addressed to the local client or a
2595: * specific downstream client based on the listen-address/port.
2596: * 6) Agent and X11-Forwarding have a similar problem and are currenly
2597: * not supported as the matching session/channel cannot be identified
2598: * easily.
2599: */
2600:
2601: /*
2602: * receive packets from downstream mux clients:
2603: * channel callback fired on read from mux client, creates
2604: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2605: * on channel creation.
2606: */
2607: int
1.367 djm 2608: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2609: {
2610: Channel *c = NULL;
2611: struct sshbuf *original = NULL, *modified = NULL;
2612: const u_char *cp;
2613: char *ctype = NULL, *listen_host = NULL;
2614: u_char type;
2615: size_t have;
1.370 djm 2616: int ret = -1, r;
1.355 djm 2617: u_int id, remote_id, listen_port;
1.354 markus 2618:
1.367 djm 2619: /* sshbuf_dump(downstream->input, stderr); */
2620: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2621: != 0) {
2622: error("%s: malformed message: %s", __func__, ssh_err(r));
2623: return -1;
2624: }
2625: if (have < 2) {
2626: error("%s: short message", __func__);
2627: return -1;
2628: }
2629: type = cp[1];
2630: /* skip padlen + type */
2631: cp += 2;
2632: have -= 2;
2633: if (ssh_packet_log_type(type))
2634: debug3("%s: channel %u: down->up: type %u", __func__,
2635: downstream->self, type);
2636:
2637: switch (type) {
2638: case SSH2_MSG_CHANNEL_OPEN:
2639: if ((original = sshbuf_from(cp, have)) == NULL ||
2640: (modified = sshbuf_new()) == NULL) {
2641: error("%s: alloc", __func__);
2642: goto out;
2643: }
2644: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2645: (r = sshbuf_get_u32(original, &id)) != 0) {
2646: error("%s: parse error %s", __func__, ssh_err(r));
2647: goto out;
2648: }
1.367 djm 2649: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2650: -1, -1, -1, 0, 0, 0, ctype, 1);
2651: c->mux_ctx = downstream; /* point to mux client */
2652: c->mux_downstream_id = id; /* original downstream id */
2653: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2654: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2655: (r = sshbuf_putb(modified, original)) != 0) {
2656: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2657: channel_free(ssh, c);
1.354 markus 2658: goto out;
2659: }
2660: break;
2661: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2662: /*
2663: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2664: * need to parse 'remote_id' instead of 'ctype'.
2665: */
2666: if ((original = sshbuf_from(cp, have)) == NULL ||
2667: (modified = sshbuf_new()) == NULL) {
2668: error("%s: alloc", __func__);
2669: goto out;
2670: }
2671: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2672: (r = sshbuf_get_u32(original, &id)) != 0) {
2673: error("%s: parse error %s", __func__, ssh_err(r));
2674: goto out;
2675: }
1.367 djm 2676: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.354 markus 2677: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
2678: c->mux_ctx = downstream; /* point to mux client */
2679: c->mux_downstream_id = id;
2680: c->remote_id = remote_id;
1.368 djm 2681: c->have_remote_id = 1;
1.354 markus 2682: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2683: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2684: (r = sshbuf_putb(modified, original)) != 0) {
2685: error("%s: compose error %s", __func__, ssh_err(r));
1.367 djm 2686: channel_free(ssh, c);
1.354 markus 2687: goto out;
2688: }
2689: break;
2690: case SSH2_MSG_GLOBAL_REQUEST:
2691: if ((original = sshbuf_from(cp, have)) == NULL) {
2692: error("%s: alloc", __func__);
2693: goto out;
2694: }
2695: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
2696: error("%s: parse error %s", __func__, ssh_err(r));
2697: goto out;
2698: }
2699: if (strcmp(ctype, "tcpip-forward") != 0) {
2700: error("%s: unsupported request %s", __func__, ctype);
2701: goto out;
2702: }
2703: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2704: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2705: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
2706: error("%s: parse error %s", __func__, ssh_err(r));
2707: goto out;
2708: }
1.355 djm 2709: if (listen_port > 65535) {
2710: error("%s: tcpip-forward for %s: bad port %u",
2711: __func__, listen_host, listen_port);
2712: goto out;
2713: }
1.354 markus 2714: /* Record that connection to this host/port is permitted. */
1.370 djm 2715: fwd_perm_list_add(ssh, FWDPERM_USER, "<mux>", -1,
1.367 djm 2716: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 2717: listen_host = NULL;
2718: break;
2719: case SSH2_MSG_CHANNEL_CLOSE:
2720: if (have < 4)
2721: break;
2722: remote_id = PEEK_U32(cp);
1.367 djm 2723: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 2724: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 2725: channel_free(ssh, c);
1.354 markus 2726: else
2727: c->flags |= CHAN_CLOSE_SENT;
2728: }
2729: break;
2730: }
2731: if (modified) {
2732: if ((r = sshpkt_start(ssh, type)) != 0 ||
2733: (r = sshpkt_putb(ssh, modified)) != 0 ||
2734: (r = sshpkt_send(ssh)) != 0) {
2735: error("%s: send %s", __func__, ssh_err(r));
2736: goto out;
2737: }
2738: } else {
2739: if ((r = sshpkt_start(ssh, type)) != 0 ||
2740: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2741: (r = sshpkt_send(ssh)) != 0) {
2742: error("%s: send %s", __func__, ssh_err(r));
2743: goto out;
2744: }
2745: }
2746: ret = 0;
2747: out:
2748: free(ctype);
2749: free(listen_host);
2750: sshbuf_free(original);
2751: sshbuf_free(modified);
2752: return ret;
2753: }
2754:
2755: /*
2756: * receive packets from upstream server and de-multiplex packets
2757: * to correct downstream:
2758: * implemented as a helper for channel input handlers,
2759: * replaces local (proxy) channel ID with downstream channel ID.
2760: */
2761: int
1.363 markus 2762: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 2763: {
2764: struct sshbuf *b = NULL;
2765: Channel *downstream;
2766: const u_char *cp = NULL;
2767: size_t len;
2768: int r;
2769:
2770: /*
2771: * When receiving packets from the peer we need to check whether we
2772: * need to forward the packets to the mux client. In this case we
2773: * restore the orignal channel id and keep track of CLOSE messages,
2774: * so we can cleanup the channel.
2775: */
2776: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2777: return 0;
2778: if ((downstream = c->mux_ctx) == NULL)
2779: return 0;
2780: switch (type) {
2781: case SSH2_MSG_CHANNEL_CLOSE:
2782: case SSH2_MSG_CHANNEL_DATA:
2783: case SSH2_MSG_CHANNEL_EOF:
2784: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2785: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2786: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2787: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2788: case SSH2_MSG_CHANNEL_SUCCESS:
2789: case SSH2_MSG_CHANNEL_FAILURE:
2790: case SSH2_MSG_CHANNEL_REQUEST:
2791: break;
2792: default:
2793: debug2("%s: channel %u: unsupported type %u", __func__,
2794: c->self, type);
2795: return 0;
2796: }
2797: if ((b = sshbuf_new()) == NULL) {
2798: error("%s: alloc reply", __func__);
2799: goto out;
2800: }
2801: /* get remaining payload (after id) */
2802: cp = sshpkt_ptr(ssh, &len);
2803: if (cp == NULL) {
2804: error("%s: no packet", __func__);
2805: goto out;
2806: }
2807: /* translate id and send to muxclient */
2808: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2809: (r = sshbuf_put_u8(b, type)) != 0 ||
2810: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2811: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 2812: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.354 markus 2813: error("%s: compose for muxclient %s", __func__, ssh_err(r));
2814: goto out;
2815: }
2816: /* sshbuf_dump(b, stderr); */
2817: if (ssh_packet_log_type(type))
2818: debug3("%s: channel %u: up->down: type %u", __func__, c->self,
2819: type);
2820: out:
2821: /* update state */
2822: switch (type) {
2823: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2824: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 2825: if (cp && len > 4) {
1.354 markus 2826: c->remote_id = PEEK_U32(cp);
1.368 djm 2827: c->have_remote_id = 1;
2828: }
1.354 markus 2829: break;
2830: case SSH2_MSG_CHANNEL_CLOSE:
2831: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 2832: channel_free(ssh, c);
1.354 markus 2833: else
2834: c->flags |= CHAN_CLOSE_RCVD;
2835: break;
2836: }
2837: sshbuf_free(b);
2838: return 1;
2839: }
1.121 markus 2840:
2841: /* -- protocol input */
1.249 djm 2842:
1.367 djm 2843: /* Parse a channel ID from the current packet */
2844: static int
2845: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
2846: {
2847: u_int32_t id;
2848: int r;
2849:
2850: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
2851: error("%s: parse id: %s", where, ssh_err(r));
2852: ssh_packet_disconnect(ssh, "Invalid %s message", what);
2853: }
2854: if (id > INT_MAX) {
2855: error("%s: bad channel id %u: %s", where, id, ssh_err(r));
2856: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
2857: }
2858: return (int)id;
2859: }
2860:
2861: /* Lookup a channel from an ID in the current packet */
2862: static Channel *
2863: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
2864: {
2865: int id = channel_parse_id(ssh, where, what);
2866: Channel *c;
2867:
2868: if ((c = channel_lookup(ssh, id)) == NULL) {
2869: ssh_packet_disconnect(ssh,
2870: "%s packet referred to nonexistent channel %d", what, id);
2871: }
2872: return c;
2873: }
2874:
1.339 markus 2875: int
1.363 markus 2876: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2877: {
1.332 djm 2878: const u_char *data;
1.367 djm 2879: size_t data_len, win_len;
2880: Channel *c = channel_from_packet_id(ssh, __func__, "data");
2881: int r;
1.25 markus 2882:
1.363 markus 2883: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2884: return 0;
1.25 markus 2885:
2886: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2887: if (c->type != SSH_CHANNEL_OPEN &&
1.372 ! markus 2888: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
! 2889: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 2890: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2891: return 0;
1.37 markus 2892:
1.25 markus 2893: /* Get the data. */
1.367 djm 2894: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0)
2895: fatal("%s: channel %d: get data: %s", __func__,
2896: c->self, ssh_err(r));
2897: ssh_packet_check_eom(ssh);
2898:
1.309 djm 2899: win_len = data_len;
2900: if (c->datagram)
2901: win_len += 4; /* string length header */
1.200 markus 2902:
2903: /*
1.367 djm 2904: * The sending side reduces its window as it sends data, so we
2905: * must 'fake' consumption of the data in order to ensure that window
2906: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 2907: */
1.358 djm 2908: if (c->ostate != CHAN_OUTPUT_OPEN) {
2909: c->local_window -= win_len;
2910: c->local_consumed += win_len;
1.339 markus 2911: return 0;
1.200 markus 2912: }
1.41 markus 2913:
1.358 djm 2914: if (win_len > c->local_maxpacket) {
1.367 djm 2915: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 2916: c->self, win_len, c->local_maxpacket);
1.367 djm 2917: return 0;
1.358 djm 2918: }
2919: if (win_len > c->local_window) {
1.367 djm 2920: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 2921: c->self, win_len, c->local_window);
2922: return 0;
1.44 markus 2923: }
1.358 djm 2924: c->local_window -= win_len;
2925:
1.367 djm 2926: if (c->datagram) {
2927: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
2928: fatal("%s: channel %d: append datagram: %s",
2929: __func__, c->self, ssh_err(r));
2930: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
2931: fatal("%s: channel %d: append data: %s",
2932: __func__, c->self, ssh_err(r));
2933:
1.339 markus 2934: return 0;
1.1 deraadt 2935: }
1.121 markus 2936:
1.339 markus 2937: int
1.363 markus 2938: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 2939: {
1.367 djm 2940: const u_char *data;
2941: size_t data_len;
2942: u_int32_t tcode;
2943: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
2944: int r;
1.44 markus 2945:
1.363 markus 2946: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2947: return 0;
1.44 markus 2948: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 2949: logit("channel %d: ext data for non open", c->self);
1.339 markus 2950: return 0;
1.172 markus 2951: }
2952: if (c->flags & CHAN_EOF_RCVD) {
2953: if (datafellows & SSH_BUG_EXTEOF)
1.367 djm 2954: debug("channel %d: accepting ext data after eof",
2955: c->self);
1.172 markus 2956: else
1.367 djm 2957: ssh_packet_disconnect(ssh, "Received extended_data "
2958: "after EOF on channel %d.", c->self);
2959: }
2960:
2961: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
2962: error("%s: parse tcode: %s", __func__, ssh_err(r));
2963: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 2964: }
2965: if (c->efd == -1 ||
2966: c->extended_usage != CHAN_EXTENDED_WRITE ||
2967: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2968: logit("channel %d: bad ext data", c->self);
1.339 markus 2969: return 0;
1.44 markus 2970: }
1.367 djm 2971: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0) {
2972: error("%s: parse data: %s", __func__, ssh_err(r));
2973: ssh_packet_disconnect(ssh, "Invalid extended_data message");
2974: }
2975: ssh_packet_check_eom(ssh);
2976:
1.44 markus 2977: if (data_len > c->local_window) {
1.367 djm 2978: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 2979: c->self, data_len, c->local_window);
1.339 markus 2980: return 0;
1.44 markus 2981: }
1.367 djm 2982: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
2983: /* XXX sshpkt_getb? */
2984: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
2985: error("%s: append: %s", __func__, ssh_err(r));
1.44 markus 2986: c->local_window -= data_len;
1.339 markus 2987: return 0;
1.44 markus 2988: }
2989:
1.339 markus 2990: int
1.363 markus 2991: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 2992: {
1.367 djm 2993: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
2994:
2995: ssh_packet_check_eom(ssh);
1.41 markus 2996:
1.363 markus 2997: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2998: return 0;
1.367 djm 2999: chan_rcvd_ieof(ssh, c);
1.133 markus 3000:
3001: /* XXX force input close */
1.156 markus 3002: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3003: debug("channel %d: FORCE input drain", c->self);
3004: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3005: if (sshbuf_len(c->input) == 0)
3006: chan_ibuf_empty(ssh, c);
1.133 markus 3007: }
1.339 markus 3008: return 0;
1.41 markus 3009: }
1.1 deraadt 3010:
1.339 markus 3011: int
1.363 markus 3012: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3013: {
1.367 djm 3014: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.151 markus 3015:
1.363 markus 3016: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3017: return 0;
1.367 djm 3018: ssh_packet_check_eom(ssh);
3019: chan_rcvd_oclose(ssh, c);
1.339 markus 3020: return 0;
1.1 deraadt 3021: }
3022:
1.339 markus 3023: int
1.363 markus 3024: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3025: {
1.367 djm 3026: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3027: u_int32_t remote_window, remote_maxpacket;
3028: int r;
1.25 markus 3029:
1.363 markus 3030: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3031: return 0;
3032: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 3033: packet_disconnect("Received open confirmation for "
1.367 djm 3034: "non-opening channel %d.", c->self);
3035: /*
3036: * Record the remote channel number and mark that the channel
3037: * is now open.
3038: */
1.368 djm 3039: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3040: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.367 djm 3041: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0) {
3042: error("%s: window/maxpacket: %s", __func__, ssh_err(r));
3043: packet_disconnect("Invalid open confirmation message");
3044: }
3045: ssh_packet_check_eom(ssh);
3046:
1.368 djm 3047: c->have_remote_id = 1;
1.367 djm 3048: c->remote_window = remote_window;
3049: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3050: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3051: if (c->open_confirm) {
1.367 djm 3052: debug2("%s: channel %d: callback start", __func__, c->self);
3053: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
3054: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3055: }
1.358 djm 3056: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3057: c->remote_window, c->remote_maxpacket);
1.339 markus 3058: return 0;
1.1 deraadt 3059: }
3060:
1.127 itojun 3061: static char *
1.114 markus 3062: reason2txt(int reason)
3063: {
1.143 deraadt 3064: switch (reason) {
1.114 markus 3065: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3066: return "administratively prohibited";
3067: case SSH2_OPEN_CONNECT_FAILED:
3068: return "connect failed";
3069: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3070: return "unknown channel type";
3071: case SSH2_OPEN_RESOURCE_SHORTAGE:
3072: return "resource shortage";
3073: }
1.117 stevesk 3074: return "unknown reason";
1.114 markus 3075: }
3076:
1.339 markus 3077: int
1.363 markus 3078: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3079: {
1.367 djm 3080: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3081: u_int32_t reason;
3082: char *msg = NULL;
3083: int r;
1.25 markus 3084:
1.363 markus 3085: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3086: return 0;
3087: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 3088: packet_disconnect("Received open failure for "
1.367 djm 3089: "non-opening channel %d.", c->self);
3090: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
3091: error("%s: reason: %s", __func__, ssh_err(r));
3092: packet_disconnect("Invalid open failure message");
3093: }
3094: if ((datafellows & SSH_BUG_OPENFAILURE) == 0) {
3095: /* skip language */
3096: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
3097: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) == 0) {
3098: error("%s: message/lang: %s", __func__, ssh_err(r));
3099: packet_disconnect("Invalid open failure message");
3100: }
1.358 djm 3101: }
1.367 djm 3102: ssh_packet_check_eom(ssh);
3103: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3104: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3105: free(msg);
3106: if (c->open_confirm) {
1.367 djm 3107: debug2("%s: channel %d: callback start", __func__, c->self);
3108: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
3109: debug2("%s: channel %d: callback done", __func__, c->self);
1.44 markus 3110: }
1.291 djm 3111: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3112: chan_mark_dead(ssh, c);
1.339 markus 3113: return 0;
1.44 markus 3114: }
3115:
1.339 markus 3116: int
1.363 markus 3117: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3118: {
1.367 djm 3119: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3120: Channel *c;
1.367 djm 3121: u_int32_t adjust;
3122: u_int new_rwin;
3123: int r;
1.1 deraadt 3124:
1.367 djm 3125: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3126: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3127: return 0;
1.372 ! markus 3128: }
1.367 djm 3129:
1.363 markus 3130: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3131: return 0;
1.367 djm 3132: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0) {
3133: error("%s: adjust: %s", __func__, ssh_err(r));
3134: packet_disconnect("Invalid window adjust message");
3135: }
3136: ssh_packet_check_eom(ssh);
3137: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3138: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3139: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3140: c->self, adjust, c->remote_window);
3141: }
3142: c->remote_window = new_rwin;
1.339 markus 3143: return 0;
1.121 markus 3144: }
1.1 deraadt 3145:
1.339 markus 3146: int
1.363 markus 3147: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3148: {
1.367 djm 3149: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3150: Channel *c;
3151: struct channel_confirm *cc;
3152:
3153: /* Reset keepalive timeout */
1.296 andreas 3154: packet_set_alive_timeouts(0);
1.275 djm 3155:
1.367 djm 3156: debug2("%s: type %d id %d", __func__, type, id);
1.275 djm 3157:
1.367 djm 3158: if ((c = channel_lookup(ssh, id)) == NULL) {
3159: logit("%s: %d: unknown", __func__, id);
1.339 markus 3160: return 0;
1.367 djm 3161: }
1.363 markus 3162: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3163: return 0;
1.367 djm 3164: ssh_packet_check_eom(ssh);
1.275 djm 3165: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3166: return 0;
1.367 djm 3167: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3168: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 3169: explicit_bzero(cc, sizeof(*cc));
1.321 djm 3170: free(cc);
1.339 markus 3171: return 0;
1.275 djm 3172: }
1.121 markus 3173:
3174: /* -- tcp forwarding */
1.135 markus 3175:
3176: void
1.367 djm 3177: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3178: {
1.367 djm 3179: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3180: }
1.121 markus 3181:
1.312 djm 3182:
3183: /*
3184: * Determine whether or not a port forward listens to loopback, the
3185: * specified address or wildcard. On the client, a specified bind
3186: * address will always override gateway_ports. On the server, a
3187: * gateway_ports of 1 (``yes'') will override the client's specification
3188: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3189: * will bind to whatever address the client asked for.
3190: *
3191: * Special-case listen_addrs are:
3192: *
3193: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3194: * "" (empty string), "*" -> wildcard v4/v6
3195: * "localhost" -> loopback v4/v6
1.334 djm 3196: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3197: */
3198: static const char *
3199: channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
1.336 millert 3200: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3201: {
3202: const char *addr = NULL;
3203: int wildcard = 0;
3204:
3205: if (listen_addr == NULL) {
3206: /* No address specified: default to gateway_ports setting */
1.336 millert 3207: if (fwd_opts->gateway_ports)
1.312 djm 3208: wildcard = 1;
1.336 millert 3209: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 3210: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
3211: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3212: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3213: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3214: wildcard = 1;
1.326 djm 3215: /*
3216: * Notify client if they requested a specific listen
3217: * address and it was overridden.
3218: */
3219: if (*listen_addr != '\0' &&
3220: strcmp(listen_addr, "0.0.0.0") != 0 &&
3221: strcmp(listen_addr, "*") != 0) {
3222: packet_send_debug("Forwarding listen address "
3223: "\"%s\" overridden by server "
3224: "GatewayPorts", listen_addr);
3225: }
1.334 djm 3226: } else if (strcmp(listen_addr, "localhost") != 0 ||
3227: strcmp(listen_addr, "127.0.0.1") == 0 ||
3228: strcmp(listen_addr, "::1") == 0) {
3229: /* Accept localhost address when GatewayPorts=yes */
3230: addr = listen_addr;
1.326 djm 3231: }
1.334 djm 3232: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3233: strcmp(listen_addr, "::1") == 0) {
3234: /*
3235: * If a specific IPv4/IPv6 localhost address has been
3236: * requested then accept it even if gateway_ports is in
3237: * effect. This allows the client to prefer IPv4 or IPv6.
3238: */
3239: addr = listen_addr;
1.312 djm 3240: }
3241: if (wildcardp != NULL)
3242: *wildcardp = wildcard;
3243: return addr;
3244: }
3245:
1.160 markus 3246: static int
1.367 djm 3247: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3248: struct Forward *fwd, int *allocated_listen_port,
3249: struct ForwardOptions *fwd_opts)
1.25 markus 3250: {
1.113 markus 3251: Channel *c;
1.226 djm 3252: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3253: struct addrinfo hints, *ai, *aitop;
1.212 djm 3254: const char *host, *addr;
1.35 markus 3255: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3256: in_port_t *lport_p;
1.25 markus 3257:
1.212 djm 3258: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3259:
1.344 millert 3260: if (is_client && fwd->connect_path != NULL) {
3261: host = fwd->connect_path;
3262: } else {
3263: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3264: fwd->listen_host : fwd->connect_host;
3265: if (host == NULL) {
3266: error("No forward host name.");
3267: return 0;
3268: }
3269: if (strlen(host) >= NI_MAXHOST) {
3270: error("Forward host name too long.");
3271: return 0;
3272: }
1.87 markus 3273: }
1.25 markus 3274:
1.312 djm 3275: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.336 millert 3276: addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard,
3277: is_client, fwd_opts);
3278: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 3279: type, wildcard, (addr == NULL) ? "NULL" : addr);
3280:
3281: /*
1.35 markus 3282: * getaddrinfo returns a loopback address if the hostname is
3283: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3284: */
1.35 markus 3285: memset(&hints, 0, sizeof(hints));
1.367 djm 3286: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3287: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3288: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3289: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3290: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3291: if (addr == NULL) {
3292: /* This really shouldn't happen */
3293: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 3294: ssh_gai_strerror(r));
1.212 djm 3295: } else {
1.336 millert 3296: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 3297: ssh_gai_strerror(r));
1.212 djm 3298: }
1.218 markus 3299: return 0;
1.212 djm 3300: }
1.295 djm 3301: if (allocated_listen_port != NULL)
3302: *allocated_listen_port = 0;
1.35 markus 3303: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3304: switch (ai->ai_family) {
3305: case AF_INET:
3306: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3307: sin_port;
3308: break;
3309: case AF_INET6:
3310: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3311: sin6_port;
3312: break;
3313: default:
1.35 markus 3314: continue;
1.295 djm 3315: }
3316: /*
3317: * If allocating a port for -R forwards, then use the
3318: * same port for all address families.
3319: */
1.367 djm 3320: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3321: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3322: *allocated_listen_port > 0)
1.295 djm 3323: *lport_p = htons(*allocated_listen_port);
3324:
1.35 markus 3325: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3326: strport, sizeof(strport),
3327: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 3328: error("%s: getnameinfo failed", __func__);
1.35 markus 3329: continue;
3330: }
3331: /* Create a port to listen for the host. */
1.300 dtucker 3332: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 3333: if (sock < 0) {
3334: /* this is no error since kernel may not support ipv6 */
3335: verbose("socket: %.100s", strerror(errno));
3336: continue;
3337: }
1.226 djm 3338:
3339: channel_set_reuseaddr(sock);
1.182 stevesk 3340:
1.295 djm 3341: debug("Local forwarding listening on %s port %s.",
3342: ntop, strport);
1.35 markus 3343:
3344: /* Bind the socket to the address. */
3345: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.367 djm 3346: /*
3347: * address can be in if use ipv6 address is
3348: * already bound
3349: */
1.35 markus 3350: verbose("bind: %.100s", strerror(errno));
3351: close(sock);
3352: continue;
3353: }
3354: /* Start listening for connections on the socket. */
1.199 markus 3355: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3356: error("listen: %.100s", strerror(errno));
3357: close(sock);
3358: continue;
3359: }
1.295 djm 3360:
3361: /*
1.336 millert 3362: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3363: * record what we got.
3364: */
1.367 djm 3365: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3366: fwd->listen_port == 0 &&
1.295 djm 3367: allocated_listen_port != NULL &&
3368: *allocated_listen_port == 0) {
1.350 djm 3369: *allocated_listen_port = get_local_port(sock);
1.295 djm 3370: debug("Allocated listen port %d",
3371: *allocated_listen_port);
3372: }
3373:
1.35 markus 3374: /* Allocate a channel number for the socket. */
1.367 djm 3375: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3376: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3377: 0, "port listener", 1);
1.293 djm 3378: c->path = xstrdup(host);
1.336 millert 3379: c->host_port = fwd->connect_port;
1.312 djm 3380: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3381: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 3382: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
3383: c->listening_port = *allocated_listen_port;
3384: else
1.336 millert 3385: c->listening_port = fwd->listen_port;
1.35 markus 3386: success = 1;
3387: }
3388: if (success == 0)
1.336 millert 3389: error("%s: cannot listen to port: %d", __func__,
3390: fwd->listen_port);
1.35 markus 3391: freeaddrinfo(aitop);
1.87 markus 3392: return success;
1.25 markus 3393: }
1.1 deraadt 3394:
1.336 millert 3395: static int
1.367 djm 3396: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3397: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3398: {
3399: struct sockaddr_un sunaddr;
3400: const char *path;
3401: Channel *c;
3402: int port, sock;
3403: mode_t omask;
3404:
3405: switch (type) {
3406: case SSH_CHANNEL_UNIX_LISTENER:
3407: if (fwd->connect_path != NULL) {
3408: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3409: error("Local connecting path too long: %s",
3410: fwd->connect_path);
3411: return 0;
3412: }
3413: path = fwd->connect_path;
3414: port = PORT_STREAMLOCAL;
3415: } else {
3416: if (fwd->connect_host == NULL) {
3417: error("No forward host name.");
3418: return 0;
3419: }
3420: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3421: error("Forward host name too long.");
3422: return 0;
3423: }
3424: path = fwd->connect_host;
3425: port = fwd->connect_port;
3426: }
3427: break;
3428: case SSH_CHANNEL_RUNIX_LISTENER:
3429: path = fwd->listen_path;
3430: port = PORT_STREAMLOCAL;
3431: break;
3432: default:
3433: error("%s: unexpected channel type %d", __func__, type);
3434: return 0;
3435: }
3436:
3437: if (fwd->listen_path == NULL) {
3438: error("No forward path name.");
3439: return 0;
3440: }
3441: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3442: error("Local listening path too long: %s", fwd->listen_path);
3443: return 0;
3444: }
3445:
3446: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
3447:
3448: /* Start a Unix domain listener. */
3449: omask = umask(fwd_opts->streamlocal_bind_mask);
3450: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3451: fwd_opts->streamlocal_bind_unlink);
3452: umask(omask);
3453: if (sock < 0)
3454: return 0;
3455:
3456: debug("Local forwarding listening on path %s.", fwd->listen_path);
3457:
3458: /* Allocate a channel number for the socket. */
1.367 djm 3459: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3460: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3461: 0, "unix listener", 1);
3462: c->path = xstrdup(path);
3463: c->host_port = port;
3464: c->listening_port = PORT_STREAMLOCAL;
3465: c->listening_addr = xstrdup(fwd->listen_path);
3466: return 1;
3467: }
3468:
3469: static int
1.367 djm 3470: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3471: const char *host, u_short port)
1.202 djm 3472: {
1.209 avsm 3473: u_int i;
3474: int found = 0;
1.202 djm 3475:
1.367 djm 3476: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3477: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3478: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3479: continue;
3480: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3481: debug2("%s: close channel %d", __func__, i);
1.367 djm 3482: channel_free(ssh, c);
1.312 djm 3483: found = 1;
3484: }
3485: }
3486:
1.367 djm 3487: return found;
1.312 djm 3488: }
3489:
1.336 millert 3490: static int
1.367 djm 3491: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3492: {
3493: u_int i;
3494: int found = 0;
3495:
1.367 djm 3496: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3497: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3498: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3499: continue;
3500: if (c->path == NULL)
3501: continue;
3502: if (strcmp(c->path, path) == 0) {
3503: debug2("%s: close channel %d", __func__, i);
1.367 djm 3504: channel_free(ssh, c);
1.336 millert 3505: found = 1;
3506: }
3507: }
3508:
1.367 djm 3509: return found;
1.336 millert 3510: }
3511:
1.312 djm 3512: int
1.367 djm 3513: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3514: {
1.367 djm 3515: if (fwd->listen_path != NULL) {
3516: return channel_cancel_rport_listener_streamlocal(ssh,
3517: fwd->listen_path);
3518: } else {
3519: return channel_cancel_rport_listener_tcpip(ssh,
3520: fwd->listen_host, fwd->listen_port);
3521: }
1.336 millert 3522: }
3523:
3524: static int
1.367 djm 3525: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3526: const char *lhost, u_short lport, int cport,
3527: struct ForwardOptions *fwd_opts)
1.312 djm 3528: {
3529: u_int i;
3530: int found = 0;
1.336 millert 3531: const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts);
1.202 djm 3532:
1.367 djm 3533: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3534: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3535: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3536: continue;
1.313 markus 3537: if (c->listening_port != lport)
1.312 djm 3538: continue;
1.313 markus 3539: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3540: /* skip dynamic forwardings */
3541: if (c->host_port == 0)
3542: continue;
3543: } else {
3544: if (c->host_port != cport)
3545: continue;
3546: }
1.312 djm 3547: if ((c->listening_addr == NULL && addr != NULL) ||
3548: (c->listening_addr != NULL && addr == NULL))
3549: continue;
3550: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3551: debug2("%s: close channel %d", __func__, i);
1.367 djm 3552: channel_free(ssh, c);
1.202 djm 3553: found = 1;
3554: }
3555: }
3556:
1.367 djm 3557: return found;
1.202 djm 3558: }
3559:
1.336 millert 3560: static int
1.367 djm 3561: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3562: {
3563: u_int i;
3564: int found = 0;
3565:
3566: if (path == NULL) {
3567: error("%s: no path specified.", __func__);
3568: return 0;
3569: }
3570:
1.367 djm 3571: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3572: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3573: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3574: continue;
3575: if (c->listening_addr == NULL)
3576: continue;
3577: if (strcmp(c->listening_addr, path) == 0) {
3578: debug2("%s: close channel %d", __func__, i);
1.367 djm 3579: channel_free(ssh, c);
1.336 millert 3580: found = 1;
3581: }
3582: }
3583:
1.367 djm 3584: return found;
1.336 millert 3585: }
3586:
3587: int
1.367 djm 3588: channel_cancel_lport_listener(struct ssh *ssh,
3589: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3590: {
1.367 djm 3591: if (fwd->listen_path != NULL) {
3592: return channel_cancel_lport_listener_streamlocal(ssh,
3593: fwd->listen_path);
3594: } else {
3595: return channel_cancel_lport_listener_tcpip(ssh,
3596: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3597: }
1.336 millert 3598: }
3599:
1.362 markus 3600: /* protocol local port fwd, used by ssh */
1.160 markus 3601: int
1.367 djm 3602: channel_setup_local_fwd_listener(struct ssh *ssh,
3603: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3604: {
1.336 millert 3605: if (fwd->listen_path != NULL) {
1.367 djm 3606: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3607: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3608: } else {
1.367 djm 3609: return channel_setup_fwd_listener_tcpip(ssh,
3610: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3611: }
1.160 markus 3612: }
3613:
3614: /* protocol v2 remote port fwd, used by sshd */
3615: int
1.367 djm 3616: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3617: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3618: {
1.336 millert 3619: if (fwd->listen_path != NULL) {
1.367 djm 3620: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3621: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3622: } else {
1.367 djm 3623: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 3624: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3625: fwd_opts);
3626: }
1.160 markus 3627: }
3628:
1.27 markus 3629: /*
1.312 djm 3630: * Translate the requested rfwd listen host to something usable for
3631: * this server.
3632: */
3633: static const char *
3634: channel_rfwd_bind_host(const char *listen_host)
3635: {
3636: if (listen_host == NULL) {
3637: if (datafellows & SSH_BUG_RFWD_ADDR)
3638: return "127.0.0.1";
3639: else
3640: return "localhost";
3641: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
3642: if (datafellows & SSH_BUG_RFWD_ADDR)
3643: return "0.0.0.0";
3644: else
3645: return "";
3646: } else
3647: return listen_host;
3648: }
3649:
3650: /*
1.27 markus 3651: * Initiate forwarding of connections to port "port" on remote host through
3652: * the secure channel to host:port from local side.
1.315 markus 3653: * Returns handle (index) for updating the dynamic listen port with
3654: * channel_update_permitted_opens().
1.27 markus 3655: */
1.253 markus 3656: int
1.367 djm 3657: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 3658: {
1.367 djm 3659: int r, success = 0, idx = -1;
3660: char *host_to_connect, *listen_host, *listen_path;
3661: int port_to_connect, listen_port;
1.73 markus 3662:
1.25 markus 3663: /* Send the forward request to the remote side. */
1.358 djm 3664: if (fwd->listen_path != NULL) {
1.367 djm 3665: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3666: (r = sshpkt_put_cstring(ssh,
3667: "streamlocal-forward@openssh.com")) != 0 ||
3668: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3669: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3670: (r = sshpkt_send(ssh)) != 0 ||
3671: (r = ssh_packet_write_wait(ssh)) != 0)
3672: fatal("%s: request streamlocal: %s",
3673: __func__, ssh_err(r));
1.336 millert 3674: } else {
1.367 djm 3675: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3676: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
3677: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3678: (r = sshpkt_put_cstring(ssh,
3679: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
3680: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
3681: (r = sshpkt_send(ssh)) != 0 ||
3682: (r = ssh_packet_write_wait(ssh)) != 0)
3683: fatal("%s: request tcpip-forward: %s",
3684: __func__, ssh_err(r));
1.73 markus 3685: }
1.358 djm 3686: /* Assume that server accepts the request */
3687: success = 1;
1.73 markus 3688: if (success) {
1.305 djm 3689: /* Record that connection to this host/port is permitted. */
1.367 djm 3690: host_to_connect = listen_host = listen_path = NULL;
3691: port_to_connect = listen_port = 0;
1.336 millert 3692: if (fwd->connect_path != NULL) {
1.367 djm 3693: host_to_connect = xstrdup(fwd->connect_path);
3694: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 3695: } else {
1.367 djm 3696: host_to_connect = xstrdup(fwd->connect_host);
3697: port_to_connect = fwd->connect_port;
1.336 millert 3698: }
3699: if (fwd->listen_path != NULL) {
1.367 djm 3700: listen_path = xstrdup(fwd->listen_path);
3701: listen_port = PORT_STREAMLOCAL;
1.336 millert 3702: } else {
1.367 djm 3703: if (fwd->listen_host != NULL)
3704: listen_host = xstrdup(fwd->listen_host);
3705: listen_port = fwd->listen_port;
3706: }
3707: idx = fwd_perm_list_add(ssh, FWDPERM_USER,
3708: host_to_connect, port_to_connect,
3709: listen_host, listen_path, listen_port, NULL);
1.44 markus 3710: }
1.367 djm 3711: return idx;
1.1 deraadt 3712: }
3713:
1.333 markus 3714: static int
3715: open_match(ForwardPermission *allowed_open, const char *requestedhost,
1.336 millert 3716: int requestedport)
1.333 markus 3717: {
3718: if (allowed_open->host_to_connect == NULL)
3719: return 0;
3720: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3721: allowed_open->port_to_connect != requestedport)
3722: return 0;
1.351 dtucker 3723: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3724: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3725: return 0;
3726: return 1;
3727: }
3728:
3729: /*
1.336 millert 3730: * Note that in the listen host/port case
1.333 markus 3731: * we don't support FWD_PERMIT_ANY_PORT and
3732: * need to translate between the configured-host (listen_host)
3733: * and what we've sent to the remote server (channel_rfwd_bind_host)
3734: */
3735: static int
1.336 millert 3736: open_listen_match_tcpip(ForwardPermission *allowed_open,
3737: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3738: {
3739: const char *allowed_host;
3740:
3741: if (allowed_open->host_to_connect == NULL)
3742: return 0;
3743: if (allowed_open->listen_port != requestedport)
3744: return 0;
1.335 djm 3745: if (!translate && allowed_open->listen_host == NULL &&
3746: requestedhost == NULL)
3747: return 1;
1.333 markus 3748: allowed_host = translate ?
3749: channel_rfwd_bind_host(allowed_open->listen_host) :
3750: allowed_open->listen_host;
3751: if (allowed_host == NULL ||
3752: strcmp(allowed_host, requestedhost) != 0)
3753: return 0;
3754: return 1;
3755: }
3756:
1.336 millert 3757: static int
3758: open_listen_match_streamlocal(ForwardPermission *allowed_open,
3759: const char *requestedpath)
3760: {
3761: if (allowed_open->host_to_connect == NULL)
3762: return 0;
3763: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3764: return 0;
3765: if (allowed_open->listen_path == NULL ||
3766: strcmp(allowed_open->listen_path, requestedpath) != 0)
3767: return 0;
3768: return 1;
3769: }
3770:
1.27 markus 3771: /*
1.208 deraadt 3772: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3773: * local side.
3774: */
1.336 millert 3775: static int
1.367 djm 3776: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
3777: const char *host, u_short port)
1.202 djm 3778: {
1.367 djm 3779: struct ssh_channels *sc = ssh->chanctxt;
3780: int r;
3781: u_int i;
3782: ForwardPermission *fp;
1.202 djm 3783:
1.367 djm 3784: for (i = 0; i < sc->num_permitted_opens; i++) {
3785: fp = &sc->permitted_opens[i];
3786: if (open_listen_match_tcpip(fp, host, port, 0))
1.202 djm 3787: break;
1.367 djm 3788: fp = NULL;
1.202 djm 3789: }
1.367 djm 3790: if (fp == NULL) {
1.202 djm 3791: debug("%s: requested forward not found", __func__);
1.312 djm 3792: return -1;
1.202 djm 3793: }
1.367 djm 3794: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3795: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
3796: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3797: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
3798: (r = sshpkt_put_u32(ssh, port)) != 0 ||
3799: (r = sshpkt_send(ssh)) != 0)
3800: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3801:
3802: fwd_perm_clear(fp); /* unregister */
1.336 millert 3803:
3804: return 0;
3805: }
3806:
3807: /*
3808: * Request cancellation of remote forwarding of Unix domain socket
3809: * path from local side.
3810: */
3811: static int
1.367 djm 3812: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3813: {
1.367 djm 3814: struct ssh_channels *sc = ssh->chanctxt;
3815: int r;
3816: u_int i;
3817: ForwardPermission *fp;
1.336 millert 3818:
1.367 djm 3819: for (i = 0; i < sc->num_permitted_opens; i++) {
3820: fp = &sc->permitted_opens[i];
3821: if (open_listen_match_streamlocal(fp, path))
1.336 millert 3822: break;
1.367 djm 3823: fp = NULL;
1.336 millert 3824: }
1.367 djm 3825: if (fp == NULL) {
1.336 millert 3826: debug("%s: requested forward not found", __func__);
3827: return -1;
3828: }
1.367 djm 3829: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3830: (r = sshpkt_put_cstring(ssh,
3831: "cancel-streamlocal-forward@openssh.com")) != 0 ||
3832: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3833: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
3834: (r = sshpkt_send(ssh)) != 0)
3835: fatal("%s: send cancel: %s", __func__, ssh_err(r));
3836:
3837: fwd_perm_clear(fp); /* unregister */
1.312 djm 3838:
3839: return 0;
1.202 djm 3840: }
3841:
3842: /*
1.336 millert 3843: * Request cancellation of remote forwarding of a connection from local side.
3844: */
3845: int
1.367 djm 3846: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3847: {
3848: if (fwd->listen_path != NULL) {
1.367 djm 3849: return channel_request_rforward_cancel_streamlocal(ssh,
3850: fwd->listen_path);
1.336 millert 3851: } else {
1.367 djm 3852: return channel_request_rforward_cancel_tcpip(ssh,
3853: fwd->listen_host,
3854: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 3855: }
1.1 deraadt 3856: }
3857:
1.99 markus 3858: /*
3859: * Permits opening to any host/port if permitted_opens[] is empty. This is
3860: * usually called by the server, because the user could connect to any port
3861: * anyway, and the server has no way to know but to trust the client anyway.
3862: */
3863: void
1.367 djm 3864: channel_permit_all_opens(struct ssh *ssh)
1.99 markus 3865: {
1.367 djm 3866: if (ssh->chanctxt->num_permitted_opens == 0)
3867: ssh->chanctxt->all_opens_permitted = 1;
1.99 markus 3868: }
3869:
1.101 markus 3870: void
1.367 djm 3871: channel_add_permitted_opens(struct ssh *ssh, char *host, int port)
1.99 markus 3872: {
1.367 djm 3873: struct ssh_channels *sc = ssh->chanctxt;
3874:
1.99 markus 3875: debug("allow port forwarding to host %s port %d", host, port);
1.367 djm 3876: fwd_perm_list_add(ssh, FWDPERM_USER, host, port, NULL, NULL, 0, NULL);
3877: sc->all_opens_permitted = 0;
1.315 markus 3878: }
3879:
3880: /*
3881: * Update the listen port for a dynamic remote forward, after
3882: * the actual 'newport' has been allocated. If 'newport' < 0 is
3883: * passed then they entry will be invalidated.
3884: */
3885: void
1.367 djm 3886: channel_update_permitted_opens(struct ssh *ssh, int idx, int newport)
1.315 markus 3887: {
1.367 djm 3888: struct ssh_channels *sc = ssh->chanctxt;
3889:
3890: if (idx < 0 || (u_int)idx >= sc->num_permitted_opens) {
3891: debug("%s: index out of range: %d num_permitted_opens %d",
3892: __func__, idx, sc->num_permitted_opens);
1.315 markus 3893: return;
3894: }
3895: debug("%s allowed port %d for forwarding to host %s port %d",
3896: newport > 0 ? "Updating" : "Removing",
3897: newport,
1.367 djm 3898: sc->permitted_opens[idx].host_to_connect,
3899: sc->permitted_opens[idx].port_to_connect);
3900: if (newport <= 0)
3901: fwd_perm_clear(&sc->permitted_opens[idx]);
3902: else {
3903: sc->permitted_opens[idx].listen_port =
1.315 markus 3904: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
3905: }
1.99 markus 3906: }
3907:
1.258 dtucker 3908: int
1.367 djm 3909: channel_add_adm_permitted_opens(struct ssh *ssh, char *host, int port)
1.257 dtucker 3910: {
1.258 dtucker 3911: debug("config allows port forwarding to host %s port %d", host, port);
1.367 djm 3912: return fwd_perm_list_add(ssh, FWDPERM_ADMIN, host, port,
3913: NULL, NULL, 0, NULL);
1.316 dtucker 3914: }
3915:
3916: void
1.367 djm 3917: channel_disable_adm_local_opens(struct ssh *ssh)
1.99 markus 3918: {
1.367 djm 3919: channel_clear_adm_permitted_opens(ssh);
3920: fwd_perm_list_add(ssh, FWDPERM_ADMIN, NULL, 0, NULL, NULL, 0, NULL);
1.257 dtucker 3921: }
3922:
3923: void
1.367 djm 3924: channel_clear_permitted_opens(struct ssh *ssh)
1.257 dtucker 3925: {
1.367 djm 3926: struct ssh_channels *sc = ssh->chanctxt;
1.99 markus 3927:
1.367 djm 3928: sc->permitted_opens = xrecallocarray(sc->permitted_opens,
3929: sc->num_permitted_opens, 0, sizeof(*sc->permitted_opens));
3930: sc->num_permitted_opens = 0;
1.278 dtucker 3931: }
3932:
3933: void
1.367 djm 3934: channel_clear_adm_permitted_opens(struct ssh *ssh)
1.278 dtucker 3935: {
1.367 djm 3936: struct ssh_channels *sc = ssh->chanctxt;
1.278 dtucker 3937:
1.367 djm 3938: sc->permitted_adm_opens = xrecallocarray(sc->permitted_adm_opens,
3939: sc->num_adm_permitted_opens, 0, sizeof(*sc->permitted_adm_opens));
3940: sc->num_adm_permitted_opens = 0;
1.99 markus 3941: }
3942:
1.314 dtucker 3943: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3944: int
3945: permitopen_port(const char *p)
3946: {
3947: int port;
3948:
3949: if (strcmp(p, "*") == 0)
3950: return FWD_PERMIT_ANY_PORT;
3951: if ((port = a2port(p)) > 0)
3952: return port;
3953: return -1;
3954: }
3955:
1.276 djm 3956: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 3957: static int
1.276 djm 3958: connect_next(struct channel_connect *cctx)
1.41 markus 3959: {
1.276 djm 3960: int sock, saved_errno;
1.336 millert 3961: struct sockaddr_un *sunaddr;
1.367 djm 3962: char ntop[NI_MAXHOST];
3963: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 3964:
1.276 djm 3965: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 3966: switch (cctx->ai->ai_family) {
3967: case AF_UNIX:
3968: /* unix:pathname instead of host:port */
3969: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
3970: strlcpy(ntop, "unix", sizeof(ntop));
3971: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
3972: break;
3973: case AF_INET:
3974: case AF_INET6:
3975: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
3976: ntop, sizeof(ntop), strport, sizeof(strport),
3977: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
3978: error("connect_next: getnameinfo failed");
3979: continue;
3980: }
3981: break;
3982: default:
1.41 markus 3983: continue;
3984: }
1.300 dtucker 3985: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
3986: cctx->ai->ai_protocol)) == -1) {
1.276 djm 3987: if (cctx->ai->ai_next == NULL)
1.186 djm 3988: error("socket: %.100s", strerror(errno));
3989: else
3990: verbose("socket: %.100s", strerror(errno));
1.41 markus 3991: continue;
3992: }
1.205 djm 3993: if (set_nonblock(sock) == -1)
3994: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 3995: if (connect(sock, cctx->ai->ai_addr,
3996: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
3997: debug("connect_next: host %.100s ([%.100s]:%s): "
3998: "%.100s", cctx->host, ntop, strport,
1.41 markus 3999: strerror(errno));
1.276 djm 4000: saved_errno = errno;
1.41 markus 4001: close(sock);
1.276 djm 4002: errno = saved_errno;
1.89 stevesk 4003: continue; /* fail -- try next */
1.41 markus 4004: }
1.336 millert 4005: if (cctx->ai->ai_family != AF_UNIX)
4006: set_nodelay(sock);
1.276 djm 4007: debug("connect_next: host %.100s ([%.100s]:%s) "
4008: "in progress, fd=%d", cctx->host, ntop, strport, sock);
4009: cctx->ai = cctx->ai->ai_next;
4010: return sock;
4011: }
4012: return -1;
4013: }
1.41 markus 4014:
1.276 djm 4015: static void
4016: channel_connect_ctx_free(struct channel_connect *cctx)
4017: {
1.321 djm 4018: free(cctx->host);
1.336 millert 4019: if (cctx->aitop) {
4020: if (cctx->aitop->ai_family == AF_UNIX)
4021: free(cctx->aitop);
4022: else
4023: freeaddrinfo(cctx->aitop);
4024: }
1.329 tedu 4025: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4026: }
4027:
1.357 dtucker 4028: /*
1.372 ! markus 4029: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4030: * passing back the failure reason if appropriate.
4031: */
1.372 ! markus 4032: static int
! 4033: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
! 4034: char *ctype, char *rname, struct channel_connect *cctx,
! 4035: int *reason, const char **errmsg)
1.276 djm 4036: {
4037: struct addrinfo hints;
4038: int gaierr;
4039: int sock = -1;
4040: char strport[NI_MAXSERV];
1.336 millert 4041:
4042: if (port == PORT_STREAMLOCAL) {
4043: struct sockaddr_un *sunaddr;
4044: struct addrinfo *ai;
4045:
4046: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4047: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 ! markus 4048: return -1;
1.336 millert 4049: }
4050:
4051: /*
4052: * Fake up a struct addrinfo for AF_UNIX connections.
4053: * channel_connect_ctx_free() must check ai_family
4054: * and use free() not freeaddirinfo() for AF_UNIX.
4055: */
4056: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4057: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4058: ai->ai_addr = (struct sockaddr *)(ai + 1);
4059: ai->ai_addrlen = sizeof(*sunaddr);
4060: ai->ai_family = AF_UNIX;
1.372 ! markus 4061: ai->ai_socktype = socktype;
1.336 millert 4062: ai->ai_protocol = PF_UNSPEC;
4063: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4064: sunaddr->sun_family = AF_UNIX;
4065: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 ! markus 4066: cctx->aitop = ai;
1.336 millert 4067: } else {
4068: memset(&hints, 0, sizeof(hints));
1.367 djm 4069: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 ! markus 4070: hints.ai_socktype = socktype;
1.336 millert 4071: snprintf(strport, sizeof strport, "%d", port);
1.372 ! markus 4072: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4073: != 0) {
4074: if (errmsg != NULL)
4075: *errmsg = ssh_gai_strerror(gaierr);
4076: if (reason != NULL)
4077: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4078: error("connect_to %.100s: unknown host (%s)", name,
4079: ssh_gai_strerror(gaierr));
1.372 ! markus 4080: return -1;
1.336 millert 4081: }
1.41 markus 4082: }
1.276 djm 4083:
1.372 ! markus 4084: cctx->host = xstrdup(name);
! 4085: cctx->port = port;
! 4086: cctx->ai = cctx->aitop;
1.276 djm 4087:
1.372 ! markus 4088: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4089: error("connect to %.100s port %d failed: %s",
1.336 millert 4090: name, port, strerror(errno));
1.372 ! markus 4091: return -1;
! 4092: }
! 4093:
! 4094: return sock;
! 4095: }
! 4096:
! 4097: /* Return CONNECTING channel to remote host:port or local socket path */
! 4098: static Channel *
! 4099: connect_to(struct ssh *ssh, const char *host, int port,
! 4100: char *ctype, char *rname)
! 4101: {
! 4102: struct channel_connect cctx;
! 4103: Channel *c;
! 4104: int sock;
! 4105:
! 4106: memset(&cctx, 0, sizeof(cctx));
! 4107: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
! 4108: &cctx, NULL, NULL);
! 4109: if (sock == -1) {
1.276 djm 4110: channel_connect_ctx_free(&cctx);
4111: return NULL;
1.41 markus 4112: }
1.367 djm 4113: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4114: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 ! markus 4115: c->host_port = port;
! 4116: c->path = xstrdup(host);
1.276 djm 4117: c->connect_ctx = cctx;
1.372 ! markus 4118:
1.276 djm 4119: return c;
1.41 markus 4120: }
1.99 markus 4121:
1.354 markus 4122: /*
4123: * returns either the newly connected channel or the downstream channel
4124: * that needs to deal with this connection.
4125: */
1.276 djm 4126: Channel *
1.367 djm 4127: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4128: u_short listen_port, char *ctype, char *rname)
1.73 markus 4129: {
1.367 djm 4130: struct ssh_channels *sc = ssh->chanctxt;
4131: u_int i;
4132: ForwardPermission *fp;
1.99 markus 4133:
1.367 djm 4134: for (i = 0; i < sc->num_permitted_opens; i++) {
4135: fp = &sc->permitted_opens[i];
4136: if (open_listen_match_tcpip(fp, listen_host, listen_port, 1)) {
4137: if (fp->downstream)
4138: return fp->downstream;
1.372 ! markus 4139: if (fp->port_to_connect == 0)
! 4140: return rdynamic_connect_prepare(ssh,
! 4141: ctype, rname);
1.367 djm 4142: return connect_to(ssh,
4143: fp->host_to_connect, fp->port_to_connect,
4144: ctype, rname);
1.276 djm 4145: }
4146: }
1.74 markus 4147: error("WARNING: Server requests forwarding for unknown listen_port %d",
4148: listen_port);
1.276 djm 4149: return NULL;
1.73 markus 4150: }
4151:
1.336 millert 4152: Channel *
1.367 djm 4153: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4154: char *ctype, char *rname)
1.336 millert 4155: {
1.367 djm 4156: struct ssh_channels *sc = ssh->chanctxt;
4157: u_int i;
4158: ForwardPermission *fp;
1.336 millert 4159:
1.367 djm 4160: for (i = 0; i < sc->num_permitted_opens; i++) {
4161: fp = &sc->permitted_opens[i];
4162: if (open_listen_match_streamlocal(fp, path)) {
4163: return connect_to(ssh,
4164: fp->host_to_connect, fp->port_to_connect,
4165: ctype, rname);
1.336 millert 4166: }
4167: }
4168: error("WARNING: Server requests forwarding for unknown path %.100s",
4169: path);
4170: return NULL;
4171: }
4172:
1.99 markus 4173: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4174: Channel *
1.367 djm 4175: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4176: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4177: {
1.367 djm 4178: struct ssh_channels *sc = ssh->chanctxt;
1.372 ! markus 4179: struct channel_connect cctx;
! 4180: Channel *c;
1.367 djm 4181: u_int i, permit, permit_adm = 1;
1.372 ! markus 4182: int sock;
1.367 djm 4183: ForwardPermission *fp;
1.99 markus 4184:
1.367 djm 4185: permit = sc->all_opens_permitted;
1.99 markus 4186: if (!permit) {
1.367 djm 4187: for (i = 0; i < sc->num_permitted_opens; i++) {
4188: fp = &sc->permitted_opens[i];
4189: if (open_match(fp, host, port)) {
1.99 markus 4190: permit = 1;
1.333 markus 4191: break;
4192: }
1.367 djm 4193: }
1.257 dtucker 4194: }
1.99 markus 4195:
1.367 djm 4196: if (sc->num_adm_permitted_opens > 0) {
1.257 dtucker 4197: permit_adm = 0;
1.367 djm 4198: for (i = 0; i < sc->num_adm_permitted_opens; i++) {
4199: fp = &sc->permitted_adm_opens[i];
4200: if (open_match(fp, host, port)) {
1.257 dtucker 4201: permit_adm = 1;
1.333 markus 4202: break;
4203: }
1.367 djm 4204: }
1.99 markus 4205: }
1.257 dtucker 4206:
4207: if (!permit || !permit_adm) {
1.188 itojun 4208: logit("Received request to connect to host %.100s port %d, "
1.99 markus 4209: "but the request was denied.", host, port);
1.357 dtucker 4210: if (reason != NULL)
4211: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4212: return NULL;
1.99 markus 4213: }
1.372 ! markus 4214:
! 4215: memset(&cctx, 0, sizeof(cctx));
! 4216: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
! 4217: &cctx, reason, errmsg);
! 4218: if (sock == -1) {
! 4219: channel_connect_ctx_free(&cctx);
! 4220: return NULL;
! 4221: }
! 4222:
! 4223: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
! 4224: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
! 4225: c->host_port = port;
! 4226: c->path = xstrdup(host);
! 4227: c->connect_ctx = cctx;
! 4228:
! 4229: return c;
1.336 millert 4230: }
4231:
4232: /* Check if connecting to that path is permitted and connect. */
4233: Channel *
1.367 djm 4234: channel_connect_to_path(struct ssh *ssh, const char *path,
4235: char *ctype, char *rname)
1.336 millert 4236: {
1.367 djm 4237: struct ssh_channels *sc = ssh->chanctxt;
4238: u_int i, permit, permit_adm = 1;
4239: ForwardPermission *fp;
1.336 millert 4240:
1.367 djm 4241: permit = sc->all_opens_permitted;
1.336 millert 4242: if (!permit) {
1.367 djm 4243: for (i = 0; i < sc->num_permitted_opens; i++) {
4244: fp = &sc->permitted_opens[i];
4245: if (open_match(fp, path, PORT_STREAMLOCAL)) {
1.336 millert 4246: permit = 1;
4247: break;
4248: }
1.367 djm 4249: }
1.336 millert 4250: }
4251:
1.367 djm 4252: if (sc->num_adm_permitted_opens > 0) {
1.336 millert 4253: permit_adm = 0;
1.367 djm 4254: for (i = 0; i < sc->num_adm_permitted_opens; i++) {
4255: fp = &sc->permitted_adm_opens[i];
4256: if (open_match(fp, path, PORT_STREAMLOCAL)) {
1.336 millert 4257: permit_adm = 1;
4258: break;
4259: }
1.367 djm 4260: }
1.336 millert 4261: }
4262:
4263: if (!permit || !permit_adm) {
4264: logit("Received request to connect to path %.100s, "
4265: "but the request was denied.", path);
4266: return NULL;
4267: }
1.367 djm 4268: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4269: }
4270:
4271: void
1.367 djm 4272: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4273: {
1.367 djm 4274: struct ssh_channels *sc = ssh->chanctxt;
4275: struct winsize ws;
4276: int r;
1.209 avsm 4277: u_int i;
1.204 djm 4278:
1.367 djm 4279: for (i = 0; i < sc->channels_alloc; i++) {
4280: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4281: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4282: continue;
1.367 djm 4283: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
1.204 djm 4284: continue;
1.367 djm 4285: channel_request_start(ssh, i, "window-change", 0);
4286: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4287: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4288: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4289: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4290: (r = sshpkt_send(ssh)) != 0)
4291: fatal("%s: channel %u: send window-change: %s",
4292: __func__, i, ssh_err(r));
1.204 djm 4293: }
1.372 ! markus 4294: }
! 4295:
! 4296: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
! 4297: static Channel *
! 4298: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
! 4299: {
! 4300: Channel *c;
! 4301: int r;
! 4302:
! 4303: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
! 4304: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
! 4305: c->host_port = 0;
! 4306: c->path = NULL;
! 4307:
! 4308: /*
! 4309: * We need to open the channel before we have a FD,
! 4310: * so that we can get SOCKS header from peer.
! 4311: */
! 4312: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
! 4313: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
! 4314: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
! 4315: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
! 4316: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
! 4317: fatal("%s: channel %i: confirm: %s", __func__,
! 4318: c->self, ssh_err(r));
! 4319: }
! 4320: return c;
! 4321: }
! 4322:
! 4323: /* Return CONNECTING socket to remote host:port or local socket path */
! 4324: static int
! 4325: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
! 4326: {
! 4327: struct channel_connect cctx;
! 4328: int sock;
! 4329:
! 4330: memset(&cctx, 0, sizeof(cctx));
! 4331: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
! 4332: NULL, &cctx, NULL, NULL);
! 4333: if (sock == -1)
! 4334: channel_connect_ctx_free(&cctx);
! 4335: else {
! 4336: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
! 4337: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
! 4338: c->connect_ctx = cctx;
! 4339: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
! 4340: }
! 4341: return sock;
1.99 markus 4342: }
4343:
1.121 markus 4344: /* -- X11 forwarding */
1.1 deraadt 4345:
1.27 markus 4346: /*
4347: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4348: * Returns 0 and a suitable display number for the DISPLAY variable
4349: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4350: */
1.141 stevesk 4351: int
1.367 djm 4352: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4353: int x11_use_localhost, int single_connection,
4354: u_int *display_numberp, int **chanids)
1.1 deraadt 4355: {
1.149 markus 4356: Channel *nc = NULL;
1.31 markus 4357: int display_number, sock;
4358: u_short port;
1.35 markus 4359: struct addrinfo hints, *ai, *aitop;
4360: char strport[NI_MAXSERV];
4361: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4362:
1.224 markus 4363: if (chanids == NULL)
4364: return -1;
4365:
1.33 markus 4366: for (display_number = x11_display_offset;
1.148 deraadt 4367: display_number < MAX_DISPLAYS;
4368: display_number++) {
1.25 markus 4369: port = 6000 + display_number;
1.35 markus 4370: memset(&hints, 0, sizeof(hints));
1.367 djm 4371: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4372: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4373: hints.ai_socktype = SOCK_STREAM;
4374: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4375: if ((gaierr = getaddrinfo(NULL, strport,
4376: &hints, &aitop)) != 0) {
1.271 dtucker 4377: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4378: return -1;
1.25 markus 4379: }
1.35 markus 4380: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4381: if (ai->ai_family != AF_INET &&
4382: ai->ai_family != AF_INET6)
1.35 markus 4383: continue;
1.300 dtucker 4384: sock = socket(ai->ai_family, ai->ai_socktype,
4385: ai->ai_protocol);
1.35 markus 4386: if (sock < 0) {
4387: error("socket: %.100s", strerror(errno));
1.203 markus 4388: freeaddrinfo(aitop);
1.141 stevesk 4389: return -1;
1.35 markus 4390: }
1.226 djm 4391: channel_set_reuseaddr(sock);
1.35 markus 4392: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.367 djm 4393: debug2("%s: bind port %d: %.100s", __func__,
4394: port, strerror(errno));
1.35 markus 4395: close(sock);
1.367 djm 4396: for (n = 0; n < num_socks; n++)
1.35 markus 4397: close(socks[n]);
4398: num_socks = 0;
4399: break;
4400: }
4401: socks[num_socks++] = sock;
4402: if (num_socks == NUM_SOCKS)
4403: break;
1.25 markus 4404: }
1.83 stevesk 4405: freeaddrinfo(aitop);
1.35 markus 4406: if (num_socks > 0)
4407: break;
1.25 markus 4408: }
4409: if (display_number >= MAX_DISPLAYS) {
4410: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4411: return -1;
1.25 markus 4412: }
4413: /* Start listening for connections on the socket. */
1.35 markus 4414: for (n = 0; n < num_socks; n++) {
4415: sock = socks[n];
1.199 markus 4416: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 4417: error("listen: %.100s", strerror(errno));
4418: close(sock);
1.141 stevesk 4419: return -1;
1.35 markus 4420: }
1.25 markus 4421: }
1.35 markus 4422:
4423: /* Allocate a channel for each socket. */
1.242 djm 4424: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4425: for (n = 0; n < num_socks; n++) {
4426: sock = socks[n];
1.367 djm 4427: nc = channel_new(ssh, "x11 listener",
1.51 markus 4428: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4429: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4430: 0, "X11 inet listener", 1);
1.167 markus 4431: nc->single_connection = single_connection;
1.224 markus 4432: (*chanids)[n] = nc->self;
1.35 markus 4433: }
1.224 markus 4434: (*chanids)[n] = -1;
1.1 deraadt 4435:
1.141 stevesk 4436: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4437: *display_numberp = display_number;
1.367 djm 4438: return 0;
1.1 deraadt 4439: }
4440:
1.127 itojun 4441: static int
1.77 markus 4442: connect_local_xsocket(u_int dnr)
1.1 deraadt 4443: {
1.25 markus 4444: int sock;
4445: struct sockaddr_un addr;
4446:
1.147 stevesk 4447: sock = socket(AF_UNIX, SOCK_STREAM, 0);
4448: if (sock < 0)
4449: error("socket: %.100s", strerror(errno));
4450: memset(&addr, 0, sizeof(addr));
4451: addr.sun_family = AF_UNIX;
4452: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4453: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4454: return sock;
4455: close(sock);
1.25 markus 4456: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4457: return -1;
1.1 deraadt 4458: }
4459:
1.51 markus 4460: int
1.367 djm 4461: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4462: {
1.248 deraadt 4463: u_int display_number;
1.25 markus 4464: const char *display;
1.51 markus 4465: char buf[1024], *cp;
1.35 markus 4466: struct addrinfo hints, *ai, *aitop;
4467: char strport[NI_MAXSERV];
1.248 deraadt 4468: int gaierr, sock = 0;
1.25 markus 4469:
4470: /* Try to open a socket for the local X server. */
4471: display = getenv("DISPLAY");
4472: if (!display) {
4473: error("DISPLAY not set.");
1.51 markus 4474: return -1;
1.25 markus 4475: }
1.27 markus 4476: /*
4477: * Now we decode the value of the DISPLAY variable and make a
4478: * connection to the real X server.
4479: */
4480:
4481: /*
4482: * Check if it is a unix domain socket. Unix domain displays are in
4483: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4484: */
1.25 markus 4485: if (strncmp(display, "unix:", 5) == 0 ||
4486: display[0] == ':') {
4487: /* Connect to the unix domain socket. */
1.367 djm 4488: if (sscanf(strrchr(display, ':') + 1, "%u",
4489: &display_number) != 1) {
4490: error("Could not parse display number from DISPLAY: "
4491: "%.100s", display);
1.51 markus 4492: return -1;
1.25 markus 4493: }
4494: /* Create a socket. */
4495: sock = connect_local_xsocket(display_number);
4496: if (sock < 0)
1.51 markus 4497: return -1;
1.25 markus 4498:
4499: /* OK, we now have a connection to the display. */
1.51 markus 4500: return sock;
1.25 markus 4501: }
1.27 markus 4502: /*
4503: * Connect to an inet socket. The DISPLAY value is supposedly
4504: * hostname:d[.s], where hostname may also be numeric IP address.
4505: */
1.145 stevesk 4506: strlcpy(buf, display, sizeof(buf));
1.25 markus 4507: cp = strchr(buf, ':');
4508: if (!cp) {
4509: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4510: return -1;
1.25 markus 4511: }
4512: *cp = 0;
1.367 djm 4513: /*
4514: * buf now contains the host name. But first we parse the
4515: * display number.
4516: */
1.248 deraadt 4517: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4518: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4519: display);
1.51 markus 4520: return -1;
1.25 markus 4521: }
1.35 markus 4522:
4523: /* Look up the host address */
4524: memset(&hints, 0, sizeof(hints));
1.367 djm 4525: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4526: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4527: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4528: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4529: error("%.100s: unknown host. (%s)", buf,
4530: ssh_gai_strerror(gaierr));
1.51 markus 4531: return -1;
1.25 markus 4532: }
1.35 markus 4533: for (ai = aitop; ai; ai = ai->ai_next) {
4534: /* Create a socket. */
1.300 dtucker 4535: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 4536: if (sock < 0) {
1.194 markus 4537: debug2("socket: %.100s", strerror(errno));
1.41 markus 4538: continue;
4539: }
4540: /* Connect it to the display. */
4541: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 4542: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4543: 6000 + display_number, strerror(errno));
4544: close(sock);
4545: continue;
4546: }
4547: /* Success */
4548: break;
1.35 markus 4549: }
4550: freeaddrinfo(aitop);
4551: if (!ai) {
1.367 djm 4552: error("connect %.100s port %u: %.100s", buf,
4553: 6000 + display_number, strerror(errno));
1.51 markus 4554: return -1;
1.25 markus 4555: }
1.162 stevesk 4556: set_nodelay(sock);
1.51 markus 4557: return sock;
4558: }
4559:
4560: /*
1.27 markus 4561: * Requests forwarding of X11 connections, generates fake authentication
4562: * data, and enables authentication spoofing.
1.121 markus 4563: * This should be called in the client only.
1.27 markus 4564: */
1.49 markus 4565: void
1.367 djm 4566: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4567: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4568: {
1.367 djm 4569: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4570: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4571: u_int i, value;
1.367 djm 4572: const char *cp;
1.25 markus 4573: char *new_data;
1.367 djm 4574: int r, screen_number;
1.25 markus 4575:
1.367 djm 4576: if (sc->x11_saved_display == NULL)
4577: sc->x11_saved_display = xstrdup(disp);
4578: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4579: error("x11_request_forwarding_with_spoofing: different "
4580: "$DISPLAY already forwarded");
4581: return;
4582: }
4583:
1.266 djm 4584: cp = strchr(disp, ':');
1.25 markus 4585: if (cp)
4586: cp = strchr(cp, '.');
4587: if (cp)
1.245 deraadt 4588: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4589: else
4590: screen_number = 0;
4591:
1.367 djm 4592: if (sc->x11_saved_proto == NULL) {
1.219 djm 4593: /* Save protocol name. */
1.367 djm 4594: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4595:
4596: /* Extract real authentication data. */
1.367 djm 4597: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4598: for (i = 0; i < data_len; i++) {
4599: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4600: fatal("x11_request_forwarding: bad "
4601: "authentication data: %.100s", data);
1.367 djm 4602: sc->x11_saved_data[i] = value;
1.219 djm 4603: }
1.367 djm 4604: sc->x11_saved_data_len = data_len;
1.353 natano 4605:
4606: /* Generate fake data of the same length. */
1.367 djm 4607: sc->x11_fake_data = xmalloc(data_len);
4608: arc4random_buf(sc->x11_fake_data, data_len);
4609: sc->x11_fake_data_len = data_len;
1.25 markus 4610: }
4611:
4612: /* Convert the fake data into hex. */
1.367 djm 4613: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 4614:
4615: /* Send the request packet. */
1.367 djm 4616: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4617: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4618: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4619: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4620: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4621: (r = sshpkt_send(ssh)) != 0 ||
4622: (r = ssh_packet_write_wait(ssh)) != 0)
4623: fatal("%s: send x11-req: %s", __func__, ssh_err(r));
1.321 djm 4624: free(new_data);
1.1 deraadt 4625: }
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