Annotation of src/usr.bin/ssh/channels.c, Revision 1.339
1.339 ! markus 1: /* $OpenBSD: channels.c,v 1.338 2014/12/11 08:20:09 djm Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.338 djm 43: #include <sys/param.h>
1.336 millert 44: #include <sys/stat.h>
1.234 stevesk 45: #include <sys/ioctl.h>
1.235 stevesk 46: #include <sys/un.h>
1.251 stevesk 47: #include <sys/socket.h>
1.261 stevesk 48: #include <sys/time.h>
1.275 djm 49: #include <sys/queue.h>
1.251 stevesk 50:
51: #include <netinet/in.h>
52: #include <arpa/inet.h>
1.233 stevesk 53:
1.254 stevesk 54: #include <errno.h>
1.298 dtucker 55: #include <fcntl.h>
1.255 stevesk 56: #include <netdb.h>
1.263 stevesk 57: #include <stdio.h>
1.262 stevesk 58: #include <stdlib.h>
1.260 stevesk 59: #include <string.h>
1.233 stevesk 60: #include <termios.h>
1.256 stevesk 61: #include <unistd.h>
1.265 deraadt 62: #include <stdarg.h>
1.1 deraadt 63:
1.265 deraadt 64: #include "xmalloc.h"
1.1 deraadt 65: #include "ssh.h"
1.82 markus 66: #include "ssh1.h"
67: #include "ssh2.h"
1.1 deraadt 68: #include "packet.h"
1.82 markus 69: #include "log.h"
70: #include "misc.h"
1.265 deraadt 71: #include "buffer.h"
1.14 markus 72: #include "channels.h"
73: #include "compat.h"
1.82 markus 74: #include "canohost.h"
1.64 markus 75: #include "key.h"
76: #include "authfd.h"
1.147 stevesk 77: #include "pathnames.h"
1.1 deraadt 78:
1.121 markus 79: /* -- channel core */
1.12 markus 80:
1.27 markus 81: /*
82: * Pointer to an array containing all allocated channels. The array is
83: * dynamically extended as needed.
84: */
1.113 markus 85: static Channel **channels = NULL;
1.1 deraadt 86:
1.27 markus 87: /*
88: * Size of the channel array. All slots of the array must always be
1.113 markus 89: * initialized (at least the type field); unused slots set to NULL
1.27 markus 90: */
1.209 avsm 91: static u_int channels_alloc = 0;
1.1 deraadt 92:
1.27 markus 93: /*
94: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 95: * updated in channel_new.
1.27 markus 96: */
1.84 markus 97: static int channel_max_fd = 0;
1.1 deraadt 98:
99:
1.121 markus 100: /* -- tcp forwarding */
1.1 deraadt 101:
1.27 markus 102: /*
103: * Data structure for storing which hosts are permitted for forward requests.
104: * The local sides of any remote forwards are stored in this array to prevent
105: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
106: * network (which might be behind a firewall).
107: */
1.336 millert 108: /* XXX: streamlocal wants a path instead of host:port */
109: /* Overload host_to_connect; we could just make this match Forward */
110: /* XXX - can we use listen_host instead of listen_path? */
1.25 markus 111: typedef struct {
1.41 markus 112: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 113: int port_to_connect; /* Connect to 'port'. */
1.333 markus 114: char *listen_host; /* Remote side should listen address. */
1.336 millert 115: char *listen_path; /* Remote side should listen path. */
116: int listen_port; /* Remote side should listen port. */
1.1 deraadt 117: } ForwardPermission;
118:
1.257 dtucker 119: /* List of all permitted host/port pairs to connect by the user. */
1.305 djm 120: static ForwardPermission *permitted_opens = NULL;
1.121 markus 121:
1.257 dtucker 122: /* List of all permitted host/port pairs to connect by the admin. */
1.305 djm 123: static ForwardPermission *permitted_adm_opens = NULL;
1.257 dtucker 124:
125: /* Number of permitted host/port pairs in the array permitted by the user. */
1.1 deraadt 126: static int num_permitted_opens = 0;
1.257 dtucker 127:
128: /* Number of permitted host/port pair in the array permitted by the admin. */
129: static int num_adm_permitted_opens = 0;
130:
1.314 dtucker 131: /* special-case port number meaning allow any port */
132: #define FWD_PERMIT_ANY_PORT 0
133:
1.27 markus 134: /*
135: * If this is true, all opens are permitted. This is the case on the server
136: * on which we have to trust the client anyway, and the user could do
137: * anything after logging in anyway.
138: */
1.1 deraadt 139: static int all_opens_permitted = 0;
140:
1.121 markus 141:
142: /* -- X11 forwarding */
143:
144: /* Maximum number of fake X11 displays to try. */
145: #define MAX_DISPLAYS 1000
146:
1.219 djm 147: /* Saved X11 local (client) display. */
148: static char *x11_saved_display = NULL;
149:
1.121 markus 150: /* Saved X11 authentication protocol name. */
151: static char *x11_saved_proto = NULL;
152:
153: /* Saved X11 authentication data. This is the real data. */
154: static char *x11_saved_data = NULL;
155: static u_int x11_saved_data_len = 0;
156:
157: /*
158: * Fake X11 authentication data. This is what the server will be sending us;
159: * we should replace any occurrences of this by the real data.
160: */
1.240 deraadt 161: static u_char *x11_fake_data = NULL;
1.121 markus 162: static u_int x11_fake_data_len;
163:
164:
165: /* -- agent forwarding */
166:
167: #define NUM_SOCKS 10
168:
1.82 markus 169: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 170: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 171:
1.121 markus 172: /* helper */
1.127 itojun 173: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 174:
1.276 djm 175: /* non-blocking connect helpers */
176: static int connect_next(struct channel_connect *);
177: static void channel_connect_ctx_free(struct channel_connect *);
178:
1.121 markus 179: /* -- channel core */
1.41 markus 180:
181: Channel *
1.229 markus 182: channel_by_id(int id)
1.41 markus 183: {
184: Channel *c;
1.113 markus 185:
1.209 avsm 186: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 187: logit("channel_by_id: %d: bad id", id);
1.41 markus 188: return NULL;
189: }
1.113 markus 190: c = channels[id];
191: if (c == NULL) {
1.229 markus 192: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 193: return NULL;
194: }
195: return c;
1.55 markus 196: }
197:
1.27 markus 198: /*
1.229 markus 199: * Returns the channel if it is allowed to receive protocol messages.
200: * Private channels, like listening sockets, may not receive messages.
201: */
202: Channel *
203: channel_lookup(int id)
204: {
205: Channel *c;
206:
207: if ((c = channel_by_id(id)) == NULL)
208: return (NULL);
209:
1.237 deraadt 210: switch (c->type) {
1.229 markus 211: case SSH_CHANNEL_X11_OPEN:
212: case SSH_CHANNEL_LARVAL:
213: case SSH_CHANNEL_CONNECTING:
214: case SSH_CHANNEL_DYNAMIC:
215: case SSH_CHANNEL_OPENING:
216: case SSH_CHANNEL_OPEN:
217: case SSH_CHANNEL_INPUT_DRAINING:
218: case SSH_CHANNEL_OUTPUT_DRAINING:
1.323 dtucker 219: case SSH_CHANNEL_ABANDONED:
1.229 markus 220: return (c);
221: }
222: logit("Non-public channel %d, type %d.", id, c->type);
223: return (NULL);
224: }
225:
226: /*
1.55 markus 227: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 228: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 229: */
1.127 itojun 230: static void
1.71 markus 231: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 232: int extusage, int nonblock, int is_tty)
1.1 deraadt 233: {
1.25 markus 234: /* Update the maximum file descriptor value. */
1.84 markus 235: channel_max_fd = MAX(channel_max_fd, rfd);
236: channel_max_fd = MAX(channel_max_fd, wfd);
237: channel_max_fd = MAX(channel_max_fd, efd);
238:
1.298 dtucker 239: if (rfd != -1)
240: fcntl(rfd, F_SETFD, FD_CLOEXEC);
241: if (wfd != -1 && wfd != rfd)
242: fcntl(wfd, F_SETFD, FD_CLOEXEC);
243: if (efd != -1 && efd != rfd && efd != wfd)
244: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 245:
1.52 markus 246: c->rfd = rfd;
247: c->wfd = wfd;
248: c->sock = (rfd == wfd) ? rfd : -1;
249: c->efd = efd;
250: c->extended_usage = extusage;
1.71 markus 251:
1.282 dtucker 252: if ((c->isatty = is_tty) != 0)
1.194 markus 253: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 254:
1.71 markus 255: /* enable nonblocking mode */
256: if (nonblock) {
257: if (rfd != -1)
258: set_nonblock(rfd);
259: if (wfd != -1)
260: set_nonblock(wfd);
261: if (efd != -1)
262: set_nonblock(efd);
263: }
1.52 markus 264: }
265:
266: /*
267: * Allocate a new channel object and set its type and socket. This will cause
268: * remote_name to be freed.
269: */
1.113 markus 270: Channel *
1.52 markus 271: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 272: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 273: {
1.209 avsm 274: int found;
275: u_int i;
1.52 markus 276: Channel *c;
1.25 markus 277:
278: /* Do initial allocation if this is the first call. */
279: if (channels_alloc == 0) {
280: channels_alloc = 10;
1.242 djm 281: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 282: for (i = 0; i < channels_alloc; i++)
1.113 markus 283: channels[i] = NULL;
1.25 markus 284: }
285: /* Try to find a free slot where to put the new channel. */
286: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 287: if (channels[i] == NULL) {
1.25 markus 288: /* Found a free slot. */
1.209 avsm 289: found = (int)i;
1.25 markus 290: break;
291: }
1.209 avsm 292: if (found < 0) {
1.27 markus 293: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 294: found = channels_alloc;
1.179 markus 295: if (channels_alloc > 10000)
296: fatal("channel_new: internal error: channels_alloc %d "
297: "too big.", channels_alloc);
1.243 djm 298: channels = xrealloc(channels, channels_alloc + 10,
299: sizeof(Channel *));
1.195 markus 300: channels_alloc += 10;
1.70 markus 301: debug2("channel: expanding %d", channels_alloc);
1.25 markus 302: for (i = found; i < channels_alloc; i++)
1.113 markus 303: channels[i] = NULL;
1.25 markus 304: }
1.113 markus 305: /* Initialize and return new channel. */
1.242 djm 306: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 307: buffer_init(&c->input);
308: buffer_init(&c->output);
1.41 markus 309: buffer_init(&c->extended);
1.293 djm 310: c->path = NULL;
1.312 djm 311: c->listening_addr = NULL;
312: c->listening_port = 0;
1.159 markus 313: c->ostate = CHAN_OUTPUT_OPEN;
314: c->istate = CHAN_INPUT_OPEN;
315: c->flags = 0;
1.281 djm 316: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0);
1.317 djm 317: c->notbefore = 0;
1.25 markus 318: c->self = found;
319: c->type = type;
1.41 markus 320: c->ctype = ctype;
1.51 markus 321: c->local_window = window;
322: c->local_window_max = window;
323: c->local_consumed = 0;
324: c->local_maxpacket = maxpack;
1.25 markus 325: c->remote_id = -1;
1.190 markus 326: c->remote_name = xstrdup(remote_name);
1.41 markus 327: c->remote_window = 0;
328: c->remote_maxpacket = 0;
1.133 markus 329: c->force_drain = 0;
1.149 markus 330: c->single_connection = 0;
1.131 markus 331: c->detach_user = NULL;
1.225 djm 332: c->detach_close = 0;
1.275 djm 333: c->open_confirm = NULL;
334: c->open_confirm_ctx = NULL;
1.65 markus 335: c->input_filter = NULL;
1.231 reyk 336: c->output_filter = NULL;
1.280 djm 337: c->filter_ctx = NULL;
338: c->filter_cleanup = NULL;
1.302 djm 339: c->ctl_chan = -1;
340: c->mux_rcb = NULL;
341: c->mux_ctx = NULL;
1.304 djm 342: c->mux_pause = 0;
1.299 markus 343: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 344: TAILQ_INIT(&c->status_confirms);
1.25 markus 345: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 346: return c;
1.1 deraadt 347: }
1.52 markus 348:
1.132 markus 349: static int
350: channel_find_maxfd(void)
351: {
1.209 avsm 352: u_int i;
353: int max = 0;
1.132 markus 354: Channel *c;
355:
356: for (i = 0; i < channels_alloc; i++) {
357: c = channels[i];
358: if (c != NULL) {
359: max = MAX(max, c->rfd);
360: max = MAX(max, c->wfd);
361: max = MAX(max, c->efd);
362: }
363: }
364: return max;
365: }
366:
367: int
368: channel_close_fd(int *fdp)
369: {
370: int ret = 0, fd = *fdp;
371:
372: if (fd != -1) {
373: ret = close(fd);
374: *fdp = -1;
375: if (fd == channel_max_fd)
376: channel_max_fd = channel_find_maxfd();
377: }
378: return ret;
379: }
380:
1.52 markus 381: /* Close all channel fd/socket. */
1.127 itojun 382: static void
1.52 markus 383: channel_close_fds(Channel *c)
384: {
1.132 markus 385: channel_close_fd(&c->sock);
386: channel_close_fd(&c->rfd);
387: channel_close_fd(&c->wfd);
388: channel_close_fd(&c->efd);
1.121 markus 389: }
390:
391: /* Free the channel and close its fd/socket. */
392: void
393: channel_free(Channel *c)
394: {
395: char *s;
1.209 avsm 396: u_int i, n;
1.275 djm 397: struct channel_confirm *cc;
1.121 markus 398:
399: for (n = 0, i = 0; i < channels_alloc; i++)
400: if (channels[i])
401: n++;
1.209 avsm 402: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 403: c->remote_name ? c->remote_name : "???", n);
404:
405: s = channel_open_message();
1.194 markus 406: debug3("channel %d: status: %s", c->self, s);
1.321 djm 407: free(s);
1.121 markus 408:
409: if (c->sock != -1)
410: shutdown(c->sock, SHUT_RDWR);
411: channel_close_fds(c);
412: buffer_free(&c->input);
413: buffer_free(&c->output);
414: buffer_free(&c->extended);
1.321 djm 415: free(c->remote_name);
416: c->remote_name = NULL;
417: free(c->path);
418: c->path = NULL;
419: free(c->listening_addr);
420: c->listening_addr = NULL;
1.275 djm 421: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
422: if (cc->abandon_cb != NULL)
423: cc->abandon_cb(c, cc->ctx);
424: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 425: explicit_bzero(cc, sizeof(*cc));
1.321 djm 426: free(cc);
1.275 djm 427: }
1.280 djm 428: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
429: c->filter_cleanup(c->self, c->filter_ctx);
1.121 markus 430: channels[c->self] = NULL;
1.321 djm 431: free(c);
1.121 markus 432: }
433:
434: void
1.126 markus 435: channel_free_all(void)
1.121 markus 436: {
1.209 avsm 437: u_int i;
1.121 markus 438:
1.126 markus 439: for (i = 0; i < channels_alloc; i++)
440: if (channels[i] != NULL)
441: channel_free(channels[i]);
1.131 markus 442: }
443:
1.121 markus 444: /*
445: * Closes the sockets/fds of all channels. This is used to close extra file
446: * descriptors after a fork.
447: */
448: void
1.142 itojun 449: channel_close_all(void)
1.121 markus 450: {
1.209 avsm 451: u_int i;
1.121 markus 452:
453: for (i = 0; i < channels_alloc; i++)
454: if (channels[i] != NULL)
455: channel_close_fds(channels[i]);
456: }
457:
458: /*
1.131 markus 459: * Stop listening to channels.
460: */
461: void
462: channel_stop_listening(void)
463: {
1.209 avsm 464: u_int i;
1.131 markus 465: Channel *c;
466:
467: for (i = 0; i < channels_alloc; i++) {
468: c = channels[i];
469: if (c != NULL) {
470: switch (c->type) {
471: case SSH_CHANNEL_AUTH_SOCKET:
472: case SSH_CHANNEL_PORT_LISTENER:
473: case SSH_CHANNEL_RPORT_LISTENER:
474: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 475: case SSH_CHANNEL_UNIX_LISTENER:
476: case SSH_CHANNEL_RUNIX_LISTENER:
1.132 markus 477: channel_close_fd(&c->sock);
1.131 markus 478: channel_free(c);
479: break;
480: }
481: }
482: }
483: }
484:
485: /*
1.121 markus 486: * Returns true if no channel has too much buffered data, and false if one or
487: * more channel is overfull.
488: */
489: int
1.142 itojun 490: channel_not_very_much_buffered_data(void)
1.121 markus 491: {
492: u_int i;
493: Channel *c;
494:
495: for (i = 0; i < channels_alloc; i++) {
496: c = channels[i];
497: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 498: #if 0
499: if (!compat20 &&
500: buffer_len(&c->input) > packet_get_maxsize()) {
1.185 markus 501: debug2("channel %d: big input buffer %d",
1.121 markus 502: c->self, buffer_len(&c->input));
503: return 0;
504: }
1.136 markus 505: #endif
1.121 markus 506: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 507: debug2("channel %d: big output buffer %u > %u",
1.136 markus 508: c->self, buffer_len(&c->output),
509: packet_get_maxsize());
1.121 markus 510: return 0;
511: }
512: }
513: }
514: return 1;
515: }
516:
517: /* Returns true if any channel is still open. */
518: int
1.142 itojun 519: channel_still_open(void)
1.121 markus 520: {
1.209 avsm 521: u_int i;
1.121 markus 522: Channel *c;
523:
524: for (i = 0; i < channels_alloc; i++) {
525: c = channels[i];
526: if (c == NULL)
527: continue;
528: switch (c->type) {
529: case SSH_CHANNEL_X11_LISTENER:
530: case SSH_CHANNEL_PORT_LISTENER:
531: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 532: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 533: case SSH_CHANNEL_CLOSED:
534: case SSH_CHANNEL_AUTH_SOCKET:
535: case SSH_CHANNEL_DYNAMIC:
536: case SSH_CHANNEL_CONNECTING:
537: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 538: case SSH_CHANNEL_ABANDONED:
1.336 millert 539: case SSH_CHANNEL_UNIX_LISTENER:
540: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 541: continue;
542: case SSH_CHANNEL_LARVAL:
543: if (!compat20)
544: fatal("cannot happen: SSH_CHANNEL_LARVAL");
545: continue;
546: case SSH_CHANNEL_OPENING:
547: case SSH_CHANNEL_OPEN:
548: case SSH_CHANNEL_X11_OPEN:
1.302 djm 549: case SSH_CHANNEL_MUX_CLIENT:
1.121 markus 550: return 1;
551: case SSH_CHANNEL_INPUT_DRAINING:
552: case SSH_CHANNEL_OUTPUT_DRAINING:
553: if (!compat13)
554: fatal("cannot happen: OUT_DRAIN");
555: return 1;
556: default:
557: fatal("channel_still_open: bad channel type %d", c->type);
558: /* NOTREACHED */
559: }
560: }
561: return 0;
562: }
563:
564: /* Returns the id of an open channel suitable for keepaliving */
565: int
1.142 itojun 566: channel_find_open(void)
1.121 markus 567: {
1.209 avsm 568: u_int i;
1.121 markus 569: Channel *c;
570:
571: for (i = 0; i < channels_alloc; i++) {
572: c = channels[i];
1.206 djm 573: if (c == NULL || c->remote_id < 0)
1.121 markus 574: continue;
575: switch (c->type) {
576: case SSH_CHANNEL_CLOSED:
577: case SSH_CHANNEL_DYNAMIC:
578: case SSH_CHANNEL_X11_LISTENER:
579: case SSH_CHANNEL_PORT_LISTENER:
580: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 581: case SSH_CHANNEL_MUX_LISTENER:
582: case SSH_CHANNEL_MUX_CLIENT:
1.121 markus 583: case SSH_CHANNEL_OPENING:
584: case SSH_CHANNEL_CONNECTING:
585: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 586: case SSH_CHANNEL_ABANDONED:
1.336 millert 587: case SSH_CHANNEL_UNIX_LISTENER:
588: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 589: continue;
590: case SSH_CHANNEL_LARVAL:
591: case SSH_CHANNEL_AUTH_SOCKET:
592: case SSH_CHANNEL_OPEN:
593: case SSH_CHANNEL_X11_OPEN:
594: return i;
595: case SSH_CHANNEL_INPUT_DRAINING:
596: case SSH_CHANNEL_OUTPUT_DRAINING:
597: if (!compat13)
598: fatal("cannot happen: OUT_DRAIN");
599: return i;
600: default:
601: fatal("channel_find_open: bad channel type %d", c->type);
602: /* NOTREACHED */
603: }
604: }
605: return -1;
606: }
607:
608:
609: /*
610: * Returns a message describing the currently open forwarded connections,
611: * suitable for sending to the client. The message contains crlf pairs for
612: * newlines.
613: */
614: char *
1.142 itojun 615: channel_open_message(void)
1.121 markus 616: {
617: Buffer buffer;
618: Channel *c;
619: char buf[1024], *cp;
1.209 avsm 620: u_int i;
1.121 markus 621:
622: buffer_init(&buffer);
623: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
624: buffer_append(&buffer, buf, strlen(buf));
625: for (i = 0; i < channels_alloc; i++) {
626: c = channels[i];
627: if (c == NULL)
628: continue;
629: switch (c->type) {
630: case SSH_CHANNEL_X11_LISTENER:
631: case SSH_CHANNEL_PORT_LISTENER:
632: case SSH_CHANNEL_RPORT_LISTENER:
633: case SSH_CHANNEL_CLOSED:
634: case SSH_CHANNEL_AUTH_SOCKET:
635: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 636: case SSH_CHANNEL_ABANDONED:
1.302 djm 637: case SSH_CHANNEL_MUX_CLIENT:
638: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 639: case SSH_CHANNEL_UNIX_LISTENER:
640: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 641: continue;
642: case SSH_CHANNEL_LARVAL:
643: case SSH_CHANNEL_OPENING:
644: case SSH_CHANNEL_CONNECTING:
645: case SSH_CHANNEL_DYNAMIC:
646: case SSH_CHANNEL_OPEN:
647: case SSH_CHANNEL_X11_OPEN:
648: case SSH_CHANNEL_INPUT_DRAINING:
649: case SSH_CHANNEL_OUTPUT_DRAINING:
1.204 djm 650: snprintf(buf, sizeof buf,
1.302 djm 651: " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cc %d)\r\n",
1.121 markus 652: c->self, c->remote_name,
653: c->type, c->remote_id,
654: c->istate, buffer_len(&c->input),
655: c->ostate, buffer_len(&c->output),
1.302 djm 656: c->rfd, c->wfd, c->ctl_chan);
1.121 markus 657: buffer_append(&buffer, buf, strlen(buf));
658: continue;
659: default:
660: fatal("channel_open_message: bad channel type %d", c->type);
661: /* NOTREACHED */
662: }
663: }
664: buffer_append(&buffer, "\0", 1);
1.337 djm 665: cp = xstrdup((char *)buffer_ptr(&buffer));
1.121 markus 666: buffer_free(&buffer);
667: return cp;
668: }
669:
670: void
671: channel_send_open(int id)
672: {
673: Channel *c = channel_lookup(id);
1.180 deraadt 674:
1.121 markus 675: if (c == NULL) {
1.188 itojun 676: logit("channel_send_open: %d: bad id", id);
1.121 markus 677: return;
678: }
1.184 markus 679: debug2("channel %d: send open", id);
1.121 markus 680: packet_start(SSH2_MSG_CHANNEL_OPEN);
681: packet_put_cstring(c->ctype);
682: packet_put_int(c->self);
683: packet_put_int(c->local_window);
684: packet_put_int(c->local_maxpacket);
685: packet_send();
686: }
687:
688: void
1.184 markus 689: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 690: {
1.184 markus 691: Channel *c = channel_lookup(id);
1.180 deraadt 692:
1.121 markus 693: if (c == NULL) {
1.188 itojun 694: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 695: return;
696: }
1.204 djm 697: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 698: packet_start(SSH2_MSG_CHANNEL_REQUEST);
699: packet_put_int(c->remote_id);
700: packet_put_cstring(service);
701: packet_put_char(wantconfirm);
702: }
1.241 deraadt 703:
1.121 markus 704: void
1.275 djm 705: channel_register_status_confirm(int id, channel_confirm_cb *cb,
706: channel_confirm_abandon_cb *abandon_cb, void *ctx)
707: {
708: struct channel_confirm *cc;
709: Channel *c;
710:
711: if ((c = channel_lookup(id)) == NULL)
712: fatal("channel_register_expect: %d: bad id", id);
713:
1.327 djm 714: cc = xcalloc(1, sizeof(*cc));
1.275 djm 715: cc->cb = cb;
716: cc->abandon_cb = abandon_cb;
717: cc->ctx = ctx;
718: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
719: }
720:
721: void
1.304 djm 722: channel_register_open_confirm(int id, channel_open_fn *fn, void *ctx)
1.121 markus 723: {
724: Channel *c = channel_lookup(id);
1.180 deraadt 725:
1.121 markus 726: if (c == NULL) {
1.287 stevesk 727: logit("channel_register_open_confirm: %d: bad id", id);
1.121 markus 728: return;
729: }
1.275 djm 730: c->open_confirm = fn;
731: c->open_confirm_ctx = ctx;
1.121 markus 732: }
1.241 deraadt 733:
1.121 markus 734: void
1.225 djm 735: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 736: {
1.229 markus 737: Channel *c = channel_by_id(id);
1.180 deraadt 738:
1.121 markus 739: if (c == NULL) {
1.188 itojun 740: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 741: return;
742: }
1.131 markus 743: c->detach_user = fn;
1.225 djm 744: c->detach_close = do_close;
1.121 markus 745: }
1.241 deraadt 746:
1.121 markus 747: void
748: channel_cancel_cleanup(int id)
749: {
1.229 markus 750: Channel *c = channel_by_id(id);
1.180 deraadt 751:
1.121 markus 752: if (c == NULL) {
1.188 itojun 753: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 754: return;
1.52 markus 755: }
1.131 markus 756: c->detach_user = NULL;
1.225 djm 757: c->detach_close = 0;
1.121 markus 758: }
1.241 deraadt 759:
1.121 markus 760: void
1.231 reyk 761: channel_register_filter(int id, channel_infilter_fn *ifn,
1.280 djm 762: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 763: {
764: Channel *c = channel_lookup(id);
1.180 deraadt 765:
1.121 markus 766: if (c == NULL) {
1.188 itojun 767: logit("channel_register_filter: %d: bad id", id);
1.121 markus 768: return;
1.52 markus 769: }
1.231 reyk 770: c->input_filter = ifn;
771: c->output_filter = ofn;
1.279 djm 772: c->filter_ctx = ctx;
1.280 djm 773: c->filter_cleanup = cfn;
1.52 markus 774: }
775:
1.49 markus 776: void
1.121 markus 777: channel_set_fds(int id, int rfd, int wfd, int efd,
1.282 dtucker 778: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 779: {
1.121 markus 780: Channel *c = channel_lookup(id);
1.180 deraadt 781:
1.121 markus 782: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
783: fatal("channel_activate for non-larval channel %d.", id);
1.282 dtucker 784: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 785: c->type = SSH_CHANNEL_OPEN;
1.168 markus 786: c->local_window = c->local_window_max = window_max;
1.121 markus 787: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
788: packet_put_int(c->remote_id);
789: packet_put_int(c->local_window);
790: packet_send();
1.1 deraadt 791: }
792:
1.27 markus 793: /*
1.41 markus 794: * 'channel_pre*' are called just before select() to add any bits relevant to
795: * channels in the select bitmasks.
796: */
797: /*
798: * 'channel_post*': perform any appropriate operations for channels which
799: * have events pending.
1.27 markus 800: */
1.237 deraadt 801: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 802: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
803: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
804:
1.259 stevesk 805: /* ARGSUSED */
1.127 itojun 806: static void
1.237 deraadt 807: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 808: {
809: FD_SET(c->sock, readset);
810: }
811:
1.259 stevesk 812: /* ARGSUSED */
1.127 itojun 813: static void
1.237 deraadt 814: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 815: {
816: debug3("channel %d: waiting for connection", c->self);
817: FD_SET(c->sock, writeset);
818: }
819:
1.127 itojun 820: static void
1.237 deraadt 821: channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 822: {
823: if (buffer_len(&c->input) < packet_get_maxsize())
824: FD_SET(c->sock, readset);
825: if (buffer_len(&c->output) > 0)
826: FD_SET(c->sock, writeset);
827: }
1.1 deraadt 828:
1.127 itojun 829: static void
1.237 deraadt 830: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 831: {
1.157 markus 832: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 833:
1.44 markus 834: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 835: limit > 0 &&
1.250 djm 836: buffer_len(&c->input) < limit &&
837: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 838: FD_SET(c->rfd, readset);
839: if (c->ostate == CHAN_OUTPUT_OPEN ||
840: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
841: if (buffer_len(&c->output) > 0) {
842: FD_SET(c->wfd, writeset);
843: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 844: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 845: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
846: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 847: else
848: chan_obuf_empty(c);
1.44 markus 849: }
850: }
851: /** XXX check close conditions, too */
1.277 markus 852: if (compat20 && c->efd != -1 &&
853: !(c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 854: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
855: buffer_len(&c->extended) > 0)
856: FD_SET(c->efd, writeset);
1.306 djm 857: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
858: (c->extended_usage == CHAN_EXTENDED_READ ||
859: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 860: buffer_len(&c->extended) < c->remote_window)
861: FD_SET(c->efd, readset);
862: }
1.204 djm 863: /* XXX: What about efd? races? */
1.44 markus 864: }
865:
1.259 stevesk 866: /* ARGSUSED */
1.127 itojun 867: static void
1.237 deraadt 868: channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 869: {
870: if (buffer_len(&c->input) == 0) {
871: packet_start(SSH_MSG_CHANNEL_CLOSE);
872: packet_put_int(c->remote_id);
873: packet_send();
874: c->type = SSH_CHANNEL_CLOSED;
1.194 markus 875: debug2("channel %d: closing after input drain.", c->self);
1.41 markus 876: }
877: }
878:
1.259 stevesk 879: /* ARGSUSED */
1.127 itojun 880: static void
1.237 deraadt 881: channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 882: {
883: if (buffer_len(&c->output) == 0)
1.113 markus 884: chan_mark_dead(c);
1.49 markus 885: else
1.41 markus 886: FD_SET(c->sock, writeset);
887: }
888:
889: /*
890: * This is a special state for X11 authentication spoofing. An opened X11
891: * connection (when authentication spoofing is being done) remains in this
892: * state until the first packet has been completely read. The authentication
893: * data in that packet is then substituted by the real data if it matches the
894: * fake data, and the channel is put into normal mode.
1.51 markus 895: * XXX All this happens at the client side.
1.121 markus 896: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 897: */
1.127 itojun 898: static int
1.121 markus 899: x11_open_helper(Buffer *b)
1.1 deraadt 900: {
1.77 markus 901: u_char *ucp;
902: u_int proto_len, data_len;
1.25 markus 903:
1.41 markus 904: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 905: if (buffer_len(b) < 12)
1.41 markus 906: return 0;
907:
908: /* Parse the lengths of variable-length fields. */
1.155 stevesk 909: ucp = buffer_ptr(b);
1.41 markus 910: if (ucp[0] == 0x42) { /* Byte order MSB first. */
911: proto_len = 256 * ucp[6] + ucp[7];
912: data_len = 256 * ucp[8] + ucp[9];
913: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
914: proto_len = ucp[6] + 256 * ucp[7];
915: data_len = ucp[8] + 256 * ucp[9];
916: } else {
1.194 markus 917: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 918: ucp[0]);
1.41 markus 919: return -1;
920: }
921:
922: /* Check if the whole packet is in buffer. */
1.121 markus 923: if (buffer_len(b) <
1.41 markus 924: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
925: return 0;
926:
927: /* Check if authentication protocol matches. */
928: if (proto_len != strlen(x11_saved_proto) ||
929: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 930: debug2("X11 connection uses different authentication protocol.");
1.41 markus 931: return -1;
932: }
933: /* Check if authentication data matches our fake data. */
934: if (data_len != x11_fake_data_len ||
1.308 djm 935: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.41 markus 936: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 937: debug2("X11 auth data does not match fake data.");
1.41 markus 938: return -1;
939: }
940: /* Check fake data length */
941: if (x11_fake_data_len != x11_saved_data_len) {
942: error("X11 fake_data_len %d != saved_data_len %d",
943: x11_fake_data_len, x11_saved_data_len);
944: return -1;
945: }
946: /*
947: * Received authentication protocol and data match
948: * our fake data. Substitute the fake data with real
949: * data.
950: */
951: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
952: x11_saved_data, x11_saved_data_len);
953: return 1;
954: }
955:
1.127 itojun 956: static void
1.237 deraadt 957: channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 958: {
1.121 markus 959: int ret = x11_open_helper(&c->output);
1.180 deraadt 960:
1.41 markus 961: if (ret == 1) {
962: /* Start normal processing for the channel. */
963: c->type = SSH_CHANNEL_OPEN;
1.47 markus 964: channel_pre_open_13(c, readset, writeset);
1.41 markus 965: } else if (ret == -1) {
966: /*
967: * We have received an X11 connection that has bad
968: * authentication information.
969: */
1.188 itojun 970: logit("X11 connection rejected because of wrong authentication.");
1.41 markus 971: buffer_clear(&c->input);
972: buffer_clear(&c->output);
1.132 markus 973: channel_close_fd(&c->sock);
1.41 markus 974: c->sock = -1;
975: c->type = SSH_CHANNEL_CLOSED;
976: packet_start(SSH_MSG_CHANNEL_CLOSE);
977: packet_put_int(c->remote_id);
978: packet_send();
979: }
980: }
1.25 markus 981:
1.127 itojun 982: static void
1.237 deraadt 983: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 984: {
1.121 markus 985: int ret = x11_open_helper(&c->output);
1.133 markus 986:
987: /* c->force_drain = 1; */
988:
1.41 markus 989: if (ret == 1) {
990: c->type = SSH_CHANNEL_OPEN;
1.157 markus 991: channel_pre_open(c, readset, writeset);
1.41 markus 992: } else if (ret == -1) {
1.188 itojun 993: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 994: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 995: chan_read_failed(c);
996: buffer_clear(&c->input);
997: chan_ibuf_empty(c);
998: buffer_clear(&c->output);
999: /* for proto v1, the peer will send an IEOF */
1000: if (compat20)
1001: chan_write_failed(c);
1002: else
1003: c->type = SSH_CHANNEL_OPEN;
1.194 markus 1004: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1005: }
1006: }
1.25 markus 1007:
1.302 djm 1008: static void
1009: channel_pre_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
1010: {
1.304 djm 1011: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.302 djm 1012: buffer_check_alloc(&c->input, CHAN_RBUF))
1013: FD_SET(c->rfd, readset);
1014: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1015: /* clear buffer immediately (discard any partial packet) */
1016: buffer_clear(&c->input);
1017: chan_ibuf_empty(c);
1018: /* Start output drain. XXX just kill chan? */
1019: chan_rcvd_oclose(c);
1020: }
1021: if (c->ostate == CHAN_OUTPUT_OPEN ||
1022: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1023: if (buffer_len(&c->output) > 0)
1024: FD_SET(c->wfd, writeset);
1025: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1026: chan_obuf_empty(c);
1027: }
1028: }
1029:
1.104 markus 1030: /* try to decode a socks4 header */
1.259 stevesk 1031: /* ARGSUSED */
1.127 itojun 1032: static int
1.237 deraadt 1033: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 1034: {
1.181 markus 1035: char *p, *host;
1.292 djm 1036: u_int len, have, i, found, need;
1.148 deraadt 1037: char username[256];
1.103 markus 1038: struct {
1039: u_int8_t version;
1040: u_int8_t command;
1041: u_int16_t dest_port;
1.104 markus 1042: struct in_addr dest_addr;
1.103 markus 1043: } s4_req, s4_rsp;
1044:
1.104 markus 1045: debug2("channel %d: decode socks4", c->self);
1.109 markus 1046:
1047: have = buffer_len(&c->input);
1048: len = sizeof(s4_req);
1049: if (have < len)
1050: return 0;
1.337 djm 1051: p = (char *)buffer_ptr(&c->input);
1.292 djm 1052:
1053: need = 1;
1054: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1055: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1056: debug2("channel %d: socks4a request", c->self);
1057: /* ... and needs an extra string (the hostname) */
1058: need = 2;
1059: }
1060: /* Check for terminating NUL on the string(s) */
1.109 markus 1061: for (found = 0, i = len; i < have; i++) {
1062: if (p[i] == '\0') {
1.292 djm 1063: found++;
1064: if (found == need)
1065: break;
1.109 markus 1066: }
1067: if (i > 1024) {
1068: /* the peer is probably sending garbage */
1069: debug("channel %d: decode socks4: too long",
1070: c->self);
1071: return -1;
1072: }
1073: }
1.292 djm 1074: if (found < need)
1.109 markus 1075: return 0;
1.103 markus 1076: buffer_get(&c->input, (char *)&s4_req.version, 1);
1077: buffer_get(&c->input, (char *)&s4_req.command, 1);
1078: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 1079: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 1080: have = buffer_len(&c->input);
1.337 djm 1081: p = (char *)buffer_ptr(&c->input);
1.331 djm 1082: if (memchr(p, '\0', have) == NULL)
1083: fatal("channel %d: decode socks4: user not nul terminated",
1084: c->self);
1.103 markus 1085: len = strlen(p);
1.106 markus 1086: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.292 djm 1087: len++; /* trailing '\0' */
1.103 markus 1088: if (len > have)
1.104 markus 1089: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 1090: c->self, len, have);
1091: strlcpy(username, p, sizeof(username));
1092: buffer_consume(&c->input, len);
1093:
1.321 djm 1094: free(c->path);
1095: c->path = NULL;
1.292 djm 1096: if (need == 1) { /* SOCKS4: one string */
1097: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1098: c->path = xstrdup(host);
1.292 djm 1099: } else { /* SOCKS4A: two strings */
1100: have = buffer_len(&c->input);
1.337 djm 1101: p = (char *)buffer_ptr(&c->input);
1.292 djm 1102: len = strlen(p);
1103: debug2("channel %d: decode socks4a: host %s/%d",
1104: c->self, p, len);
1105: len++; /* trailing '\0' */
1106: if (len > have)
1107: fatal("channel %d: decode socks4a: len %d > have %d",
1108: c->self, len, have);
1.293 djm 1109: if (len > NI_MAXHOST) {
1.292 djm 1110: error("channel %d: hostname \"%.100s\" too long",
1111: c->self, p);
1112: return -1;
1113: }
1.293 djm 1114: c->path = xstrdup(p);
1.292 djm 1115: buffer_consume(&c->input, len);
1116: }
1.103 markus 1117: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1118:
1.194 markus 1119: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1120: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1121:
1.104 markus 1122: if (s4_req.command != 1) {
1.292 djm 1123: debug("channel %d: cannot handle: %s cn %d",
1124: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1125: return -1;
1.103 markus 1126: }
1.104 markus 1127: s4_rsp.version = 0; /* vn: 0 for reply */
1128: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1129: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1130: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1131: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1132: return 1;
1133: }
1134:
1.193 markus 1135: /* try to decode a socks5 header */
1136: #define SSH_SOCKS5_AUTHDONE 0x1000
1137: #define SSH_SOCKS5_NOAUTH 0x00
1138: #define SSH_SOCKS5_IPV4 0x01
1139: #define SSH_SOCKS5_DOMAIN 0x03
1140: #define SSH_SOCKS5_IPV6 0x04
1141: #define SSH_SOCKS5_CONNECT 0x01
1142: #define SSH_SOCKS5_SUCCESS 0x00
1143:
1.259 stevesk 1144: /* ARGSUSED */
1.193 markus 1145: static int
1.237 deraadt 1146: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1147: {
1148: struct {
1149: u_int8_t version;
1150: u_int8_t command;
1151: u_int8_t reserved;
1152: u_int8_t atyp;
1153: } s5_req, s5_rsp;
1154: u_int16_t dest_port;
1.324 djm 1155: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1156: u_char *p;
1.252 djm 1157: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1158:
1159: debug2("channel %d: decode socks5", c->self);
1160: p = buffer_ptr(&c->input);
1161: if (p[0] != 0x05)
1162: return -1;
1163: have = buffer_len(&c->input);
1164: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1165: /* format: ver | nmethods | methods */
1.198 djm 1166: if (have < 2)
1.193 markus 1167: return 0;
1168: nmethods = p[1];
1169: if (have < nmethods + 2)
1170: return 0;
1171: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1172: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1173: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1174: found = 1;
1175: break;
1176: }
1177: }
1178: if (!found) {
1179: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1180: c->self);
1181: return -1;
1182: }
1183: buffer_consume(&c->input, nmethods + 2);
1184: buffer_put_char(&c->output, 0x05); /* version */
1185: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1186: FD_SET(c->sock, writeset);
1187: c->flags |= SSH_SOCKS5_AUTHDONE;
1188: debug2("channel %d: socks5 auth done", c->self);
1189: return 0; /* need more */
1190: }
1191: debug2("channel %d: socks5 post auth", c->self);
1192: if (have < sizeof(s5_req)+1)
1193: return 0; /* need more */
1.247 deraadt 1194: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1195: if (s5_req.version != 0x05 ||
1196: s5_req.command != SSH_SOCKS5_CONNECT ||
1197: s5_req.reserved != 0x00) {
1.194 markus 1198: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1199: return -1;
1200: }
1.213 deraadt 1201: switch (s5_req.atyp){
1.193 markus 1202: case SSH_SOCKS5_IPV4:
1203: addrlen = 4;
1204: af = AF_INET;
1205: break;
1206: case SSH_SOCKS5_DOMAIN:
1207: addrlen = p[sizeof(s5_req)];
1208: af = -1;
1209: break;
1210: case SSH_SOCKS5_IPV6:
1211: addrlen = 16;
1212: af = AF_INET6;
1213: break;
1214: default:
1.194 markus 1215: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1216: return -1;
1217: }
1.252 djm 1218: need = sizeof(s5_req) + addrlen + 2;
1219: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1220: need++;
1221: if (have < need)
1.193 markus 1222: return 0;
1223: buffer_consume(&c->input, sizeof(s5_req));
1224: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1225: buffer_consume(&c->input, 1); /* host string length */
1.324 djm 1226: buffer_get(&c->input, &dest_addr, addrlen);
1.193 markus 1227: buffer_get(&c->input, (char *)&dest_port, 2);
1228: dest_addr[addrlen] = '\0';
1.321 djm 1229: free(c->path);
1230: c->path = NULL;
1.293 djm 1231: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1232: if (addrlen >= NI_MAXHOST) {
1.293 djm 1233: error("channel %d: dynamic request: socks5 hostname "
1234: "\"%.100s\" too long", c->self, dest_addr);
1235: return -1;
1236: }
1237: c->path = xstrdup(dest_addr);
1238: } else {
1239: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1240: return -1;
1241: c->path = xstrdup(ntop);
1242: }
1.193 markus 1243: c->host_port = ntohs(dest_port);
1.198 djm 1244:
1.194 markus 1245: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1246: c->self, c->path, c->host_port, s5_req.command);
1247:
1248: s5_rsp.version = 0x05;
1249: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1250: s5_rsp.reserved = 0; /* ignored */
1251: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1252: dest_port = 0; /* ignored */
1253:
1.246 deraadt 1254: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1.325 djm 1255: buffer_put_int(&c->output, ntohl(INADDR_ANY)); /* bind address */
1.246 deraadt 1256: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1257: return 1;
1.301 dtucker 1258: }
1259:
1260: Channel *
1.302 djm 1261: channel_connect_stdio_fwd(const char *host_to_connect, u_short port_to_connect,
1262: int in, int out)
1.301 dtucker 1263: {
1264: Channel *c;
1265:
1266: debug("channel_connect_stdio_fwd %s:%d", host_to_connect,
1267: port_to_connect);
1268:
1269: c = channel_new("stdio-forward", SSH_CHANNEL_OPENING, in, out,
1270: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1271: 0, "stdio-forward", /*nonblock*/0);
1272:
1273: c->path = xstrdup(host_to_connect);
1274: c->host_port = port_to_connect;
1275: c->listening_port = 0;
1276: c->force_drain = 1;
1277:
1278: channel_register_fds(c, in, out, -1, 0, 1, 0);
1279: port_open_helper(c, "direct-tcpip");
1280:
1281: return c;
1.193 markus 1282: }
1283:
1.104 markus 1284: /* dynamic port forwarding */
1.127 itojun 1285: static void
1.237 deraadt 1286: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1287: {
1288: u_char *p;
1.217 djm 1289: u_int have;
1290: int ret;
1.103 markus 1291:
1.104 markus 1292: have = buffer_len(&c->input);
1293: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1294: /* buffer_dump(&c->input); */
1.104 markus 1295: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1296: if (have < 3) {
1.104 markus 1297: /* need more */
1298: FD_SET(c->sock, readset);
1299: return;
1300: }
1301: /* try to guess the protocol */
1302: p = buffer_ptr(&c->input);
1303: switch (p[0]) {
1304: case 0x04:
1305: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1306: break;
1307: case 0x05:
1308: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1309: break;
1310: default:
1311: ret = -1;
1312: break;
1313: }
1314: if (ret < 0) {
1.113 markus 1315: chan_mark_dead(c);
1.104 markus 1316: } else if (ret == 0) {
1317: debug2("channel %d: pre_dynamic: need more", c->self);
1318: /* need more */
1319: FD_SET(c->sock, readset);
1320: } else {
1321: /* switch to the next state */
1322: c->type = SSH_CHANNEL_OPENING;
1323: port_open_helper(c, "direct-tcpip");
1324: }
1.103 markus 1325: }
1326:
1.41 markus 1327: /* This is our fake X11 server socket. */
1.259 stevesk 1328: /* ARGSUSED */
1.127 itojun 1329: static void
1.237 deraadt 1330: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1331: {
1.113 markus 1332: Channel *nc;
1.285 djm 1333: struct sockaddr_storage addr;
1.320 markus 1334: int newsock, oerrno;
1.41 markus 1335: socklen_t addrlen;
1.85 markus 1336: char buf[16384], *remote_ipaddr;
1.51 markus 1337: int remote_port;
1.25 markus 1338:
1.41 markus 1339: if (FD_ISSET(c->sock, readset)) {
1340: debug("X11 connection requested.");
1341: addrlen = sizeof(addr);
1.285 djm 1342: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.149 markus 1343: if (c->single_connection) {
1.320 markus 1344: oerrno = errno;
1.194 markus 1345: debug2("single_connection: closing X11 listener.");
1.149 markus 1346: channel_close_fd(&c->sock);
1347: chan_mark_dead(c);
1.320 markus 1348: errno = oerrno;
1.149 markus 1349: }
1.41 markus 1350: if (newsock < 0) {
1.320 markus 1351: if (errno != EINTR && errno != EWOULDBLOCK &&
1352: errno != ECONNABORTED)
1353: error("accept: %.100s", strerror(errno));
1.317 djm 1354: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1355: c->notbefore = monotime() + 1;
1.41 markus 1356: return;
1357: }
1.162 stevesk 1358: set_nodelay(newsock);
1.85 markus 1359: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1360: remote_port = get_peer_port(newsock);
1.41 markus 1361: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1362: remote_ipaddr, remote_port);
1.51 markus 1363:
1.113 markus 1364: nc = channel_new("accepted x11 socket",
1.51 markus 1365: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1366: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.51 markus 1367: if (compat20) {
1368: packet_start(SSH2_MSG_CHANNEL_OPEN);
1369: packet_put_cstring("x11");
1.113 markus 1370: packet_put_int(nc->self);
1.149 markus 1371: packet_put_int(nc->local_window_max);
1372: packet_put_int(nc->local_maxpacket);
1.85 markus 1373: /* originator ipaddr and port */
1374: packet_put_cstring(remote_ipaddr);
1.57 markus 1375: if (datafellows & SSH_BUG_X11FWD) {
1.194 markus 1376: debug2("ssh2 x11 bug compat mode");
1.57 markus 1377: } else {
1378: packet_put_int(remote_port);
1379: }
1.51 markus 1380: packet_send();
1381: } else {
1382: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1383: packet_put_int(nc->self);
1.121 markus 1384: if (packet_get_protocol_flags() &
1385: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1386: packet_put_cstring(buf);
1.51 markus 1387: packet_send();
1388: }
1.321 djm 1389: free(remote_ipaddr);
1.41 markus 1390: }
1391: }
1.25 markus 1392:
1.127 itojun 1393: static void
1.103 markus 1394: port_open_helper(Channel *c, char *rtype)
1395: {
1396: char buf[1024];
1.328 djm 1397: char *local_ipaddr = get_local_ipaddr(c->sock);
1.330 djm 1398: int local_port = c->sock == -1 ? 65536 : get_sock_port(c->sock, 1);
1.103 markus 1399: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1400: int remote_port = get_peer_port(c->sock);
1.303 djm 1401:
1402: if (remote_port == -1) {
1403: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1404: free(remote_ipaddr);
1.303 djm 1405: remote_ipaddr = xstrdup("127.0.0.1");
1406: remote_port = 65535;
1407: }
1.103 markus 1408:
1409: snprintf(buf, sizeof buf,
1410: "%s: listening port %d for %.100s port %d, "
1.328 djm 1411: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1412: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1413: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1414:
1.321 djm 1415: free(c->remote_name);
1.103 markus 1416: c->remote_name = xstrdup(buf);
1417:
1418: if (compat20) {
1419: packet_start(SSH2_MSG_CHANNEL_OPEN);
1420: packet_put_cstring(rtype);
1421: packet_put_int(c->self);
1422: packet_put_int(c->local_window_max);
1423: packet_put_int(c->local_maxpacket);
1.336 millert 1424: if (strcmp(rtype, "direct-tcpip") == 0) {
1.103 markus 1425: /* target host, port */
1426: packet_put_cstring(c->path);
1427: packet_put_int(c->host_port);
1.336 millert 1428: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1429: /* target path */
1430: packet_put_cstring(c->path);
1431: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1432: /* listen path */
1433: packet_put_cstring(c->path);
1.103 markus 1434: } else {
1435: /* listen address, port */
1436: packet_put_cstring(c->path);
1.328 djm 1437: packet_put_int(local_port);
1.103 markus 1438: }
1.336 millert 1439: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1440: /* reserved for future owner/mode info */
1441: packet_put_cstring("");
1442: } else {
1443: /* originator host and port */
1444: packet_put_cstring(remote_ipaddr);
1445: packet_put_int((u_int)remote_port);
1446: }
1.103 markus 1447: packet_send();
1448: } else {
1449: packet_start(SSH_MSG_PORT_OPEN);
1450: packet_put_int(c->self);
1451: packet_put_cstring(c->path);
1452: packet_put_int(c->host_port);
1.121 markus 1453: if (packet_get_protocol_flags() &
1454: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1455: packet_put_cstring(c->remote_name);
1456: packet_send();
1457: }
1.321 djm 1458: free(remote_ipaddr);
1.328 djm 1459: free(local_ipaddr);
1.103 markus 1460: }
1461:
1.226 djm 1462: static void
1463: channel_set_reuseaddr(int fd)
1464: {
1465: int on = 1;
1466:
1467: /*
1468: * Set socket options.
1469: * Allow local port reuse in TIME_WAIT.
1470: */
1471: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1472: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1473: }
1474:
1.41 markus 1475: /*
1476: * This socket is listening for connections to a forwarded TCP/IP port.
1477: */
1.259 stevesk 1478: /* ARGSUSED */
1.127 itojun 1479: static void
1.237 deraadt 1480: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1481: {
1.103 markus 1482: Channel *nc;
1.285 djm 1483: struct sockaddr_storage addr;
1.113 markus 1484: int newsock, nextstate;
1.41 markus 1485: socklen_t addrlen;
1.103 markus 1486: char *rtype;
1.73 markus 1487:
1.41 markus 1488: if (FD_ISSET(c->sock, readset)) {
1489: debug("Connection to port %d forwarding "
1490: "to %.100s port %d requested.",
1491: c->listening_port, c->path, c->host_port);
1.103 markus 1492:
1.137 markus 1493: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1494: nextstate = SSH_CHANNEL_OPENING;
1495: rtype = "forwarded-tcpip";
1.336 millert 1496: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1497: nextstate = SSH_CHANNEL_OPENING;
1498: rtype = "forwarded-streamlocal@openssh.com";
1499: } else if (c->host_port == PORT_STREAMLOCAL) {
1500: nextstate = SSH_CHANNEL_OPENING;
1501: rtype = "direct-streamlocal@openssh.com";
1502: } else if (c->host_port == 0) {
1503: nextstate = SSH_CHANNEL_DYNAMIC;
1504: rtype = "dynamic-tcpip";
1.137 markus 1505: } else {
1.336 millert 1506: nextstate = SSH_CHANNEL_OPENING;
1507: rtype = "direct-tcpip";
1.137 markus 1508: }
1.103 markus 1509:
1.41 markus 1510: addrlen = sizeof(addr);
1.285 djm 1511: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1512: if (newsock < 0) {
1.320 markus 1513: if (errno != EINTR && errno != EWOULDBLOCK &&
1514: errno != ECONNABORTED)
1515: error("accept: %.100s", strerror(errno));
1.317 djm 1516: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1517: c->notbefore = monotime() + 1;
1.41 markus 1518: return;
1519: }
1.336 millert 1520: if (c->host_port != PORT_STREAMLOCAL)
1521: set_nodelay(newsock);
1.190 markus 1522: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1523: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1524: nc->listening_port = c->listening_port;
1525: nc->host_port = c->host_port;
1.293 djm 1526: if (c->path != NULL)
1527: nc->path = xstrdup(c->path);
1.103 markus 1528:
1.299 markus 1529: if (nextstate != SSH_CHANNEL_DYNAMIC)
1.103 markus 1530: port_open_helper(nc, rtype);
1.41 markus 1531: }
1532: }
1.25 markus 1533:
1.41 markus 1534: /*
1535: * This is the authentication agent socket listening for connections from
1536: * clients.
1537: */
1.259 stevesk 1538: /* ARGSUSED */
1.127 itojun 1539: static void
1.237 deraadt 1540: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1541: {
1.113 markus 1542: Channel *nc;
1543: int newsock;
1.285 djm 1544: struct sockaddr_storage addr;
1.41 markus 1545: socklen_t addrlen;
1.25 markus 1546:
1.41 markus 1547: if (FD_ISSET(c->sock, readset)) {
1548: addrlen = sizeof(addr);
1.285 djm 1549: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1550: if (newsock < 0) {
1.317 djm 1551: error("accept from auth socket: %.100s",
1552: strerror(errno));
1553: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1554: c->notbefore = monotime() + 1;
1.41 markus 1555: return;
1556: }
1.113 markus 1557: nc = channel_new("accepted auth socket",
1.73 markus 1558: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1559: c->local_window_max, c->local_maxpacket,
1.190 markus 1560: 0, "accepted auth socket", 1);
1.73 markus 1561: if (compat20) {
1562: packet_start(SSH2_MSG_CHANNEL_OPEN);
1563: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1564: packet_put_int(nc->self);
1.73 markus 1565: packet_put_int(c->local_window_max);
1566: packet_put_int(c->local_maxpacket);
1567: } else {
1568: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1569: packet_put_int(nc->self);
1.73 markus 1570: }
1.41 markus 1571: packet_send();
1572: }
1573: }
1.25 markus 1574:
1.259 stevesk 1575: /* ARGSUSED */
1.127 itojun 1576: static void
1.237 deraadt 1577: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1578: {
1.276 djm 1579: int err = 0, sock;
1.129 stevesk 1580: socklen_t sz = sizeof(err);
1.114 markus 1581:
1.75 markus 1582: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1583: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1584: err = errno;
1585: error("getsockopt SO_ERROR failed");
1586: }
1587: if (err == 0) {
1.276 djm 1588: debug("channel %d: connected to %s port %d",
1589: c->self, c->connect_ctx.host, c->connect_ctx.port);
1590: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1591: c->type = SSH_CHANNEL_OPEN;
1592: if (compat20) {
1593: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1594: packet_put_int(c->remote_id);
1595: packet_put_int(c->self);
1596: packet_put_int(c->local_window);
1597: packet_put_int(c->local_maxpacket);
1598: } else {
1599: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1600: packet_put_int(c->remote_id);
1601: packet_put_int(c->self);
1602: }
1.75 markus 1603: } else {
1.276 djm 1604: debug("channel %d: connection failed: %s",
1.114 markus 1605: c->self, strerror(err));
1.276 djm 1606: /* Try next address, if any */
1607: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1608: close(c->sock);
1609: c->sock = c->rfd = c->wfd = sock;
1610: channel_max_fd = channel_find_maxfd();
1611: return;
1612: }
1613: /* Exhausted all addresses */
1614: error("connect_to %.100s port %d: failed.",
1615: c->connect_ctx.host, c->connect_ctx.port);
1616: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1617: if (compat20) {
1618: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1619: packet_put_int(c->remote_id);
1620: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1621: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1622: packet_put_cstring(strerror(err));
1623: packet_put_cstring("");
1624: }
1.75 markus 1625: } else {
1.114 markus 1626: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1627: packet_put_int(c->remote_id);
1.75 markus 1628: }
1.114 markus 1629: chan_mark_dead(c);
1.75 markus 1630: }
1.114 markus 1631: packet_send();
1.75 markus 1632: }
1633: }
1634:
1.259 stevesk 1635: /* ARGSUSED */
1.127 itojun 1636: static int
1.237 deraadt 1637: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1638: {
1.214 markus 1639: char buf[CHAN_RBUF];
1.41 markus 1640: int len;
1.25 markus 1641:
1.118 markus 1642: if (c->rfd != -1 &&
1.41 markus 1643: FD_ISSET(c->rfd, readset)) {
1644: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1645: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1646: return 1;
1.41 markus 1647: if (len <= 0) {
1.194 markus 1648: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1649: c->self, c->rfd, len);
1.104 markus 1650: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1651: debug2("channel %d: not open", c->self);
1.113 markus 1652: chan_mark_dead(c);
1.103 markus 1653: return -1;
1.104 markus 1654: } else if (compat13) {
1.158 markus 1655: buffer_clear(&c->output);
1.41 markus 1656: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.194 markus 1657: debug2("channel %d: input draining.", c->self);
1.25 markus 1658: } else {
1.41 markus 1659: chan_read_failed(c);
1.25 markus 1660: }
1.41 markus 1661: return -1;
1662: }
1.143 deraadt 1663: if (c->input_filter != NULL) {
1.66 markus 1664: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1665: debug2("channel %d: filter stops", c->self);
1.65 markus 1666: chan_read_failed(c);
1667: }
1.228 reyk 1668: } else if (c->datagram) {
1669: buffer_put_string(&c->input, buf, len);
1.65 markus 1670: } else {
1671: buffer_append(&c->input, buf, len);
1672: }
1.41 markus 1673: }
1674: return 1;
1675: }
1.241 deraadt 1676:
1.259 stevesk 1677: /* ARGSUSED */
1.127 itojun 1678: static int
1.237 deraadt 1679: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1680: {
1.95 markus 1681: struct termios tio;
1.231 reyk 1682: u_char *data = NULL, *buf;
1.309 djm 1683: u_int dlen, olen = 0;
1.41 markus 1684: int len;
1.25 markus 1685:
1.41 markus 1686: /* Send buffered output data to the socket. */
1.118 markus 1687: if (c->wfd != -1 &&
1.41 markus 1688: FD_ISSET(c->wfd, writeset) &&
1689: buffer_len(&c->output) > 0) {
1.309 djm 1690: olen = buffer_len(&c->output);
1.231 reyk 1691: if (c->output_filter != NULL) {
1692: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1693: debug2("channel %d: filter stops", c->self);
1.232 reyk 1694: if (c->type != SSH_CHANNEL_OPEN)
1695: chan_mark_dead(c);
1696: else
1697: chan_write_failed(c);
1698: return -1;
1.231 reyk 1699: }
1700: } else if (c->datagram) {
1701: buf = data = buffer_get_string(&c->output, &dlen);
1702: } else {
1703: buf = data = buffer_ptr(&c->output);
1704: dlen = buffer_len(&c->output);
1705: }
1706:
1.228 reyk 1707: if (c->datagram) {
1708: /* ignore truncated writes, datagrams might get lost */
1.231 reyk 1709: len = write(c->wfd, buf, dlen);
1.321 djm 1710: free(data);
1.228 reyk 1711: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1712: return 1;
1713: if (len <= 0) {
1714: if (c->type != SSH_CHANNEL_OPEN)
1715: chan_mark_dead(c);
1716: else
1717: chan_write_failed(c);
1718: return -1;
1719: }
1.309 djm 1720: goto out;
1.228 reyk 1721: }
1.231 reyk 1722:
1723: len = write(c->wfd, buf, dlen);
1.53 markus 1724: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1725: return 1;
1.41 markus 1726: if (len <= 0) {
1.104 markus 1727: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1728: debug2("channel %d: not open", c->self);
1.113 markus 1729: chan_mark_dead(c);
1.104 markus 1730: return -1;
1731: } else if (compat13) {
1.158 markus 1732: buffer_clear(&c->output);
1.194 markus 1733: debug2("channel %d: input draining.", c->self);
1.41 markus 1734: c->type = SSH_CHANNEL_INPUT_DRAINING;
1735: } else {
1736: chan_write_failed(c);
1737: }
1738: return -1;
1.91 markus 1739: }
1.231 reyk 1740: if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1741: if (tcgetattr(c->wfd, &tio) == 0 &&
1742: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1743: /*
1744: * Simulate echo to reduce the impact of
1.96 markus 1745: * traffic analysis. We need to match the
1.95 markus 1746: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1747: * (4 byte channel id + buf)
1.91 markus 1748: */
1.95 markus 1749: packet_send_ignore(4 + len);
1.91 markus 1750: packet_send();
1751: }
1.25 markus 1752: }
1.41 markus 1753: buffer_consume(&c->output, len);
1.44 markus 1754: }
1.309 djm 1755: out:
1756: if (compat20 && olen > 0)
1757: c->local_consumed += olen - buffer_len(&c->output);
1.44 markus 1758: return 1;
1759: }
1.241 deraadt 1760:
1.127 itojun 1761: static int
1.237 deraadt 1762: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1763: {
1.214 markus 1764: char buf[CHAN_RBUF];
1.44 markus 1765: int len;
1766:
1.45 markus 1767: /** XXX handle drain efd, too */
1.44 markus 1768: if (c->efd != -1) {
1769: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1770: FD_ISSET(c->efd, writeset) &&
1771: buffer_len(&c->extended) > 0) {
1772: len = write(c->efd, buffer_ptr(&c->extended),
1773: buffer_len(&c->extended));
1.70 markus 1774: debug2("channel %d: written %d to efd %d",
1.44 markus 1775: c->self, len, c->efd);
1.93 markus 1776: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1777: return 1;
1778: if (len <= 0) {
1779: debug2("channel %d: closing write-efd %d",
1780: c->self, c->efd);
1.132 markus 1781: channel_close_fd(&c->efd);
1.93 markus 1782: } else {
1.44 markus 1783: buffer_consume(&c->extended, len);
1784: c->local_consumed += len;
1785: }
1.306 djm 1786: } else if (c->efd != -1 &&
1787: (c->extended_usage == CHAN_EXTENDED_READ ||
1788: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 1789: FD_ISSET(c->efd, readset)) {
1790: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1791: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1792: c->self, len, c->efd);
1.93 markus 1793: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1794: return 1;
1795: if (len <= 0) {
1796: debug2("channel %d: closing read-efd %d",
1.45 markus 1797: c->self, c->efd);
1.132 markus 1798: channel_close_fd(&c->efd);
1.93 markus 1799: } else {
1.306 djm 1800: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
1801: debug3("channel %d: discard efd",
1802: c->self);
1803: } else
1804: buffer_append(&c->extended, buf, len);
1.93 markus 1805: }
1.44 markus 1806: }
1807: }
1808: return 1;
1809: }
1.241 deraadt 1810:
1.259 stevesk 1811: /* ARGSUSED */
1.127 itojun 1812: static int
1.93 markus 1813: channel_check_window(Channel *c)
1.44 markus 1814: {
1.104 markus 1815: if (c->type == SSH_CHANNEL_OPEN &&
1816: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 1817: ((c->local_window_max - c->local_window >
1.269 markus 1818: c->local_maxpacket*3) ||
1819: c->local_window < c->local_window_max/2) &&
1.44 markus 1820: c->local_consumed > 0) {
1821: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1822: packet_put_int(c->remote_id);
1823: packet_put_int(c->local_consumed);
1824: packet_send();
1.70 markus 1825: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1826: c->self, c->local_window,
1827: c->local_consumed);
1828: c->local_window += c->local_consumed;
1829: c->local_consumed = 0;
1.1 deraadt 1830: }
1.41 markus 1831: return 1;
1.1 deraadt 1832: }
1833:
1.127 itojun 1834: static void
1.237 deraadt 1835: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1836: {
1837: channel_handle_rfd(c, readset, writeset);
1838: channel_handle_wfd(c, readset, writeset);
1.157 markus 1839: if (!compat20)
1.137 markus 1840: return;
1.44 markus 1841: channel_handle_efd(c, readset, writeset);
1.93 markus 1842: channel_check_window(c);
1.44 markus 1843: }
1844:
1.302 djm 1845: static u_int
1846: read_mux(Channel *c, u_int need)
1847: {
1848: char buf[CHAN_RBUF];
1849: int len;
1850: u_int rlen;
1851:
1852: if (buffer_len(&c->input) < need) {
1853: rlen = need - buffer_len(&c->input);
1854: len = read(c->rfd, buf, MIN(rlen, CHAN_RBUF));
1855: if (len <= 0) {
1856: if (errno != EINTR && errno != EAGAIN) {
1857: debug2("channel %d: ctl read<=0 rfd %d len %d",
1858: c->self, c->rfd, len);
1859: chan_read_failed(c);
1860: return 0;
1861: }
1862: } else
1863: buffer_append(&c->input, buf, len);
1864: }
1865: return buffer_len(&c->input);
1866: }
1867:
1868: static void
1869: channel_post_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
1870: {
1871: u_int need;
1872: ssize_t len;
1873:
1874: if (!compat20)
1875: fatal("%s: entered with !compat20", __func__);
1876:
1.304 djm 1877: if (c->rfd != -1 && !c->mux_pause && FD_ISSET(c->rfd, readset) &&
1.302 djm 1878: (c->istate == CHAN_INPUT_OPEN ||
1879: c->istate == CHAN_INPUT_WAIT_DRAIN)) {
1880: /*
1881: * Don't not read past the precise end of packets to
1882: * avoid disrupting fd passing.
1883: */
1884: if (read_mux(c, 4) < 4) /* read header */
1885: return;
1886: need = get_u32(buffer_ptr(&c->input));
1887: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1888: if (need > CHANNEL_MUX_MAX_PACKET) {
1889: debug2("channel %d: packet too big %u > %u",
1890: c->self, CHANNEL_MUX_MAX_PACKET, need);
1891: chan_rcvd_oclose(c);
1892: return;
1893: }
1894: if (read_mux(c, need + 4) < need + 4) /* read body */
1895: return;
1896: if (c->mux_rcb(c) != 0) {
1897: debug("channel %d: mux_rcb failed", c->self);
1898: chan_mark_dead(c);
1899: return;
1900: }
1901: }
1902:
1903: if (c->wfd != -1 && FD_ISSET(c->wfd, writeset) &&
1904: buffer_len(&c->output) > 0) {
1905: len = write(c->wfd, buffer_ptr(&c->output),
1906: buffer_len(&c->output));
1907: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1908: return;
1909: if (len <= 0) {
1910: chan_mark_dead(c);
1911: return;
1912: }
1913: buffer_consume(&c->output, len);
1914: }
1915: }
1916:
1917: static void
1918: channel_post_mux_listener(Channel *c, fd_set *readset, fd_set *writeset)
1919: {
1920: Channel *nc;
1921: struct sockaddr_storage addr;
1922: socklen_t addrlen;
1923: int newsock;
1924: uid_t euid;
1925: gid_t egid;
1926:
1927: if (!FD_ISSET(c->sock, readset))
1928: return;
1929:
1930: debug("multiplexing control connection");
1931:
1932: /*
1933: * Accept connection on control socket
1934: */
1935: memset(&addr, 0, sizeof(addr));
1936: addrlen = sizeof(addr);
1937: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
1938: &addrlen)) == -1) {
1939: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 1940: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1941: c->notbefore = monotime() + 1;
1.302 djm 1942: return;
1943: }
1944:
1945: if (getpeereid(newsock, &euid, &egid) < 0) {
1946: error("%s getpeereid failed: %s", __func__,
1947: strerror(errno));
1948: close(newsock);
1949: return;
1950: }
1951: if ((euid != 0) && (getuid() != euid)) {
1952: error("multiplex uid mismatch: peer euid %u != uid %u",
1953: (u_int)euid, (u_int)getuid());
1954: close(newsock);
1955: return;
1956: }
1957: nc = channel_new("multiplex client", SSH_CHANNEL_MUX_CLIENT,
1958: newsock, newsock, -1, c->local_window_max,
1959: c->local_maxpacket, 0, "mux-control", 1);
1960: nc->mux_rcb = c->mux_rcb;
1961: debug3("%s: new mux channel %d fd %d", __func__,
1962: nc->self, nc->sock);
1963: /* establish state */
1964: nc->mux_rcb(nc);
1965: /* mux state transitions must not elicit protocol messages */
1966: nc->flags |= CHAN_LOCAL;
1967: }
1968:
1.259 stevesk 1969: /* ARGSUSED */
1.127 itojun 1970: static void
1.237 deraadt 1971: channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
1.1 deraadt 1972: {
1.41 markus 1973: int len;
1.180 deraadt 1974:
1.41 markus 1975: /* Send buffered output data to the socket. */
1976: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1977: len = write(c->sock, buffer_ptr(&c->output),
1978: buffer_len(&c->output));
1979: if (len <= 0)
1.158 markus 1980: buffer_clear(&c->output);
1.41 markus 1981: else
1982: buffer_consume(&c->output, len);
1983: }
1984: }
1.25 markus 1985:
1.127 itojun 1986: static void
1.44 markus 1987: channel_handler_init_20(void)
1988: {
1.157 markus 1989: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1990: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1991: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1992: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.336 millert 1993: channel_pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
1994: channel_pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
1.51 markus 1995: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1996: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1997: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1998: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.302 djm 1999: channel_pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2000: channel_pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
1.44 markus 2001:
1.157 markus 2002: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 2003: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 2004: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.336 millert 2005: channel_post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2006: channel_post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
1.51 markus 2007: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 2008: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 2009: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 2010: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.302 djm 2011: channel_post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2012: channel_post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.44 markus 2013: }
2014:
1.127 itojun 2015: static void
1.41 markus 2016: channel_handler_init_13(void)
2017: {
2018: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
2019: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
2020: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2021: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2022: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2023: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
2024: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 2025: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 2026: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 2027:
1.157 markus 2028: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 2029: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2030: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2031: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2032: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 2033: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 2034: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 2035: }
1.25 markus 2036:
1.127 itojun 2037: static void
1.41 markus 2038: channel_handler_init_15(void)
2039: {
1.157 markus 2040: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 2041: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 2042: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2043: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2044: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 2045: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 2046: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 2047:
1.41 markus 2048: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2049: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2050: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 2051: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 2052: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 2053: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 2054: }
1.27 markus 2055:
1.127 itojun 2056: static void
1.41 markus 2057: channel_handler_init(void)
2058: {
2059: int i;
1.180 deraadt 2060:
1.148 deraadt 2061: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 2062: channel_pre[i] = NULL;
2063: channel_post[i] = NULL;
2064: }
1.44 markus 2065: if (compat20)
2066: channel_handler_init_20();
2067: else if (compat13)
1.41 markus 2068: channel_handler_init_13();
2069: else
2070: channel_handler_init_15();
2071: }
1.25 markus 2072:
1.140 markus 2073: /* gc dead channels */
2074: static void
2075: channel_garbage_collect(Channel *c)
2076: {
2077: if (c == NULL)
2078: return;
2079: if (c->detach_user != NULL) {
1.225 djm 2080: if (!chan_is_dead(c, c->detach_close))
1.140 markus 2081: return;
1.194 markus 2082: debug2("channel %d: gc: notify user", c->self);
1.140 markus 2083: c->detach_user(c->self, NULL);
2084: /* if we still have a callback */
2085: if (c->detach_user != NULL)
2086: return;
1.194 markus 2087: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2088: }
2089: if (!chan_is_dead(c, 1))
2090: return;
1.194 markus 2091: debug2("channel %d: garbage collecting", c->self);
1.140 markus 2092: channel_free(c);
2093: }
2094:
1.127 itojun 2095: static void
1.317 djm 2096: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset,
2097: time_t *unpause_secs)
1.41 markus 2098: {
2099: static int did_init = 0;
1.299 markus 2100: u_int i, oalloc;
1.41 markus 2101: Channel *c;
1.317 djm 2102: time_t now;
1.25 markus 2103:
1.41 markus 2104: if (!did_init) {
2105: channel_handler_init();
2106: did_init = 1;
2107: }
1.322 dtucker 2108: now = monotime();
1.317 djm 2109: if (unpause_secs != NULL)
2110: *unpause_secs = 0;
1.299 markus 2111: for (i = 0, oalloc = channels_alloc; i < oalloc; i++) {
1.113 markus 2112: c = channels[i];
2113: if (c == NULL)
1.41 markus 2114: continue;
1.299 markus 2115: if (c->delayed) {
2116: if (ftab == channel_pre)
2117: c->delayed = 0;
2118: else
2119: continue;
2120: }
1.317 djm 2121: if (ftab[c->type] != NULL) {
2122: /*
2123: * Run handlers that are not paused.
2124: */
2125: if (c->notbefore <= now)
2126: (*ftab[c->type])(c, readset, writeset);
2127: else if (unpause_secs != NULL) {
2128: /*
2129: * Collect the time that the earliest
2130: * channel comes off pause.
2131: */
2132: debug3("%s: chan %d: skip for %d more seconds",
2133: __func__, c->self,
2134: (int)(c->notbefore - now));
2135: if (*unpause_secs == 0 ||
2136: (c->notbefore - now) < *unpause_secs)
2137: *unpause_secs = c->notbefore - now;
2138: }
2139: }
1.140 markus 2140: channel_garbage_collect(c);
1.1 deraadt 2141: }
1.317 djm 2142: if (unpause_secs != NULL && *unpause_secs != 0)
2143: debug3("%s: first channel unpauses in %d seconds",
2144: __func__, (int)*unpause_secs);
1.1 deraadt 2145: }
2146:
1.121 markus 2147: /*
2148: * Allocate/update select bitmasks and add any bits relevant to channels in
2149: * select bitmasks.
2150: */
1.49 markus 2151: void
1.100 markus 2152: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.318 djm 2153: u_int *nallocp, time_t *minwait_secs, int rekeying)
1.41 markus 2154: {
1.243 djm 2155: u_int n, sz, nfdset;
1.84 markus 2156:
2157: n = MAX(*maxfdp, channel_max_fd);
2158:
1.243 djm 2159: nfdset = howmany(n+1, NFDBITS);
2160: /* Explicitly test here, because xrealloc isn't always called */
2161: if (nfdset && SIZE_T_MAX / nfdset < sizeof(fd_mask))
2162: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2163: sz = nfdset * sizeof(fd_mask);
2164:
1.132 markus 2165: /* perhaps check sz < nalloc/2 and shrink? */
2166: if (*readsetp == NULL || sz > *nallocp) {
1.243 djm 2167: *readsetp = xrealloc(*readsetp, nfdset, sizeof(fd_mask));
2168: *writesetp = xrealloc(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2169: *nallocp = sz;
1.84 markus 2170: }
1.132 markus 2171: *maxfdp = n;
1.84 markus 2172: memset(*readsetp, 0, sz);
2173: memset(*writesetp, 0, sz);
2174:
1.100 markus 2175: if (!rekeying)
1.317 djm 2176: channel_handler(channel_pre, *readsetp, *writesetp,
2177: minwait_secs);
1.41 markus 2178: }
2179:
1.121 markus 2180: /*
2181: * After select, perform any appropriate operations for channels which have
2182: * events pending.
2183: */
1.49 markus 2184: void
1.237 deraadt 2185: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 2186: {
1.317 djm 2187: channel_handler(channel_post, readset, writeset, NULL);
1.41 markus 2188: }
2189:
1.121 markus 2190:
1.84 markus 2191: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2192: void
1.142 itojun 2193: channel_output_poll(void)
1.1 deraadt 2194: {
1.41 markus 2195: Channel *c;
1.209 avsm 2196: u_int i, len;
1.1 deraadt 2197:
1.25 markus 2198: for (i = 0; i < channels_alloc; i++) {
1.113 markus 2199: c = channels[i];
2200: if (c == NULL)
2201: continue;
1.37 markus 2202:
1.121 markus 2203: /*
2204: * We are only interested in channels that can have buffered
2205: * incoming data.
2206: */
1.37 markus 2207: if (compat13) {
1.41 markus 2208: if (c->type != SSH_CHANNEL_OPEN &&
2209: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 2210: continue;
2211: } else {
1.41 markus 2212: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 2213: continue;
2214: }
1.46 markus 2215: if (compat20 &&
2216: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2217: /* XXX is this true? */
1.140 markus 2218: debug3("channel %d: will not send data after close", c->self);
1.44 markus 2219: continue;
2220: }
1.25 markus 2221:
2222: /* Get the amount of buffered data for this channel. */
1.93 markus 2223: if ((c->istate == CHAN_INPUT_OPEN ||
2224: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
2225: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 2226: if (c->datagram) {
2227: if (len > 0) {
2228: u_char *data;
2229: u_int dlen;
2230:
2231: data = buffer_get_string(&c->input,
2232: &dlen);
1.309 djm 2233: if (dlen > c->remote_window ||
2234: dlen > c->remote_maxpacket) {
2235: debug("channel %d: datagram "
2236: "too big for channel",
2237: c->self);
1.321 djm 2238: free(data);
1.309 djm 2239: continue;
2240: }
1.228 reyk 2241: packet_start(SSH2_MSG_CHANNEL_DATA);
2242: packet_put_int(c->remote_id);
2243: packet_put_string(data, dlen);
2244: packet_send();
2245: c->remote_window -= dlen + 4;
1.321 djm 2246: free(data);
1.228 reyk 2247: }
2248: continue;
2249: }
1.121 markus 2250: /*
2251: * Send some data for the other side over the secure
2252: * connection.
2253: */
1.44 markus 2254: if (compat20) {
2255: if (len > c->remote_window)
2256: len = c->remote_window;
2257: if (len > c->remote_maxpacket)
2258: len = c->remote_maxpacket;
1.25 markus 2259: } else {
1.44 markus 2260: if (packet_is_interactive()) {
2261: if (len > 1024)
2262: len = 512;
2263: } else {
2264: /* Keep the packets at reasonable size. */
2265: if (len > packet_get_maxsize()/2)
2266: len = packet_get_maxsize()/2;
2267: }
1.25 markus 2268: }
1.41 markus 2269: if (len > 0) {
1.44 markus 2270: packet_start(compat20 ?
2271: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 2272: packet_put_int(c->remote_id);
2273: packet_put_string(buffer_ptr(&c->input), len);
2274: packet_send();
2275: buffer_consume(&c->input, len);
2276: c->remote_window -= len;
2277: }
2278: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 2279: if (compat13)
2280: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 2281: /*
2282: * input-buffer is empty and read-socket shutdown:
1.172 markus 2283: * tell peer, that we will not send more data: send IEOF.
2284: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 2285: */
1.172 markus 2286: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 2287: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2288: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 2289: else
2290: chan_ibuf_empty(c);
1.25 markus 2291: }
1.44 markus 2292: /* Send extended data, i.e. stderr */
2293: if (compat20 &&
1.172 markus 2294: !(c->flags & CHAN_EOF_SENT) &&
1.44 markus 2295: c->remote_window > 0 &&
2296: (len = buffer_len(&c->extended)) > 0 &&
2297: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 2298: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 2299: c->self, c->remote_window, buffer_len(&c->extended),
2300: c->extended_usage);
1.44 markus 2301: if (len > c->remote_window)
2302: len = c->remote_window;
2303: if (len > c->remote_maxpacket)
2304: len = c->remote_maxpacket;
2305: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
2306: packet_put_int(c->remote_id);
2307: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
2308: packet_put_string(buffer_ptr(&c->extended), len);
2309: packet_send();
2310: buffer_consume(&c->extended, len);
2311: c->remote_window -= len;
1.93 markus 2312: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 2313: }
1.25 markus 2314: }
1.1 deraadt 2315: }
2316:
1.121 markus 2317:
2318: /* -- protocol input */
1.249 djm 2319:
2320: /* ARGSUSED */
1.339 ! markus 2321: int
1.154 markus 2322: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2323: {
1.37 markus 2324: int id;
1.332 djm 2325: const u_char *data;
1.309 djm 2326: u_int data_len, win_len;
1.41 markus 2327: Channel *c;
1.25 markus 2328:
2329: /* Get the channel number and verify it. */
1.37 markus 2330: id = packet_get_int();
1.41 markus 2331: c = channel_lookup(id);
2332: if (c == NULL)
1.37 markus 2333: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 2334:
2335: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2336: if (c->type != SSH_CHANNEL_OPEN &&
2337: c->type != SSH_CHANNEL_X11_OPEN)
1.339 ! markus 2338: return 0;
1.37 markus 2339:
1.25 markus 2340: /* Get the data. */
1.274 markus 2341: data = packet_get_string_ptr(&data_len);
1.309 djm 2342: win_len = data_len;
2343: if (c->datagram)
2344: win_len += 4; /* string length header */
1.200 markus 2345:
2346: /*
2347: * Ignore data for protocol > 1.3 if output end is no longer open.
2348: * For protocol 2 the sending side is reducing its window as it sends
2349: * data, so we must 'fake' consumption of the data in order to ensure
2350: * that window updates are sent back. Otherwise the connection might
2351: * deadlock.
2352: */
2353: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
2354: if (compat20) {
1.309 djm 2355: c->local_window -= win_len;
2356: c->local_consumed += win_len;
1.200 markus 2357: }
1.339 ! markus 2358: return 0;
1.200 markus 2359: }
1.41 markus 2360:
1.143 deraadt 2361: if (compat20) {
1.309 djm 2362: if (win_len > c->local_maxpacket) {
1.188 itojun 2363: logit("channel %d: rcvd big packet %d, maxpack %d",
1.309 djm 2364: c->self, win_len, c->local_maxpacket);
1.44 markus 2365: }
1.309 djm 2366: if (win_len > c->local_window) {
1.188 itojun 2367: logit("channel %d: rcvd too much data %d, win %d",
1.309 djm 2368: c->self, win_len, c->local_window);
1.339 ! markus 2369: return 0;
1.44 markus 2370: }
1.309 djm 2371: c->local_window -= win_len;
1.44 markus 2372: }
1.228 reyk 2373: if (c->datagram)
2374: buffer_put_string(&c->output, data, data_len);
2375: else
2376: buffer_append(&c->output, data, data_len);
1.274 markus 2377: packet_check_eom();
1.339 ! markus 2378: return 0;
1.1 deraadt 2379: }
1.121 markus 2380:
1.249 djm 2381: /* ARGSUSED */
1.339 ! markus 2382: int
1.154 markus 2383: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2384: {
2385: int id;
2386: char *data;
1.177 markus 2387: u_int data_len, tcode;
1.44 markus 2388: Channel *c;
2389:
2390: /* Get the channel number and verify it. */
2391: id = packet_get_int();
2392: c = channel_lookup(id);
2393:
2394: if (c == NULL)
2395: packet_disconnect("Received extended_data for bad channel %d.", id);
2396: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2397: logit("channel %d: ext data for non open", id);
1.339 ! markus 2398: return 0;
1.172 markus 2399: }
2400: if (c->flags & CHAN_EOF_RCVD) {
2401: if (datafellows & SSH_BUG_EXTEOF)
2402: debug("channel %d: accepting ext data after eof", id);
2403: else
2404: packet_disconnect("Received extended_data after EOF "
2405: "on channel %d.", id);
1.44 markus 2406: }
2407: tcode = packet_get_int();
2408: if (c->efd == -1 ||
2409: c->extended_usage != CHAN_EXTENDED_WRITE ||
2410: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2411: logit("channel %d: bad ext data", c->self);
1.339 ! markus 2412: return 0;
1.44 markus 2413: }
2414: data = packet_get_string(&data_len);
1.152 markus 2415: packet_check_eom();
1.44 markus 2416: if (data_len > c->local_window) {
1.188 itojun 2417: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2418: c->self, data_len, c->local_window);
1.321 djm 2419: free(data);
1.339 ! markus 2420: return 0;
1.44 markus 2421: }
1.70 markus 2422: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2423: c->local_window -= data_len;
2424: buffer_append(&c->extended, data, data_len);
1.321 djm 2425: free(data);
1.339 ! markus 2426: return 0;
1.44 markus 2427: }
2428:
1.249 djm 2429: /* ARGSUSED */
1.339 ! markus 2430: int
1.154 markus 2431: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2432: {
2433: int id;
2434: Channel *c;
2435:
2436: id = packet_get_int();
1.152 markus 2437: packet_check_eom();
1.41 markus 2438: c = channel_lookup(id);
2439: if (c == NULL)
2440: packet_disconnect("Received ieof for nonexistent channel %d.", id);
2441: chan_rcvd_ieof(c);
1.133 markus 2442:
2443: /* XXX force input close */
1.156 markus 2444: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2445: debug("channel %d: FORCE input drain", c->self);
2446: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2447: if (buffer_len(&c->input) == 0)
2448: chan_ibuf_empty(c);
1.133 markus 2449: }
1.339 ! markus 2450: return 0;
1.41 markus 2451: }
1.1 deraadt 2452:
1.249 djm 2453: /* ARGSUSED */
1.339 ! markus 2454: int
1.154 markus 2455: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2456: {
1.41 markus 2457: int id;
2458: Channel *c;
1.1 deraadt 2459:
1.41 markus 2460: id = packet_get_int();
1.152 markus 2461: packet_check_eom();
1.41 markus 2462: c = channel_lookup(id);
2463: if (c == NULL)
2464: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 2465:
2466: /*
2467: * Send a confirmation that we have closed the channel and no more
2468: * data is coming for it.
2469: */
1.25 markus 2470: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 2471: packet_put_int(c->remote_id);
1.25 markus 2472: packet_send();
2473:
1.27 markus 2474: /*
2475: * If the channel is in closed state, we have sent a close request,
2476: * and the other side will eventually respond with a confirmation.
2477: * Thus, we cannot free the channel here, because then there would be
2478: * no-one to receive the confirmation. The channel gets freed when
2479: * the confirmation arrives.
2480: */
1.41 markus 2481: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 2482: /*
2483: * Not a closed channel - mark it as draining, which will
2484: * cause it to be freed later.
2485: */
1.158 markus 2486: buffer_clear(&c->input);
1.41 markus 2487: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 2488: }
1.339 ! markus 2489: return 0;
1.1 deraadt 2490: }
2491:
1.41 markus 2492: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.249 djm 2493: /* ARGSUSED */
1.339 ! markus 2494: int
1.154 markus 2495: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2496: {
2497: int id = packet_get_int();
2498: Channel *c = channel_lookup(id);
1.151 markus 2499:
1.152 markus 2500: packet_check_eom();
1.41 markus 2501: if (c == NULL)
2502: packet_disconnect("Received oclose for nonexistent channel %d.", id);
2503: chan_rcvd_oclose(c);
1.339 ! markus 2504: return 0;
1.41 markus 2505: }
1.1 deraadt 2506:
1.249 djm 2507: /* ARGSUSED */
1.339 ! markus 2508: int
1.154 markus 2509: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2510: {
1.41 markus 2511: int id = packet_get_int();
2512: Channel *c = channel_lookup(id);
1.1 deraadt 2513:
1.152 markus 2514: packet_check_eom();
1.41 markus 2515: if (c == NULL)
2516: packet_disconnect("Received close confirmation for "
2517: "out-of-range channel %d.", id);
1.323 dtucker 2518: if (c->type != SSH_CHANNEL_CLOSED && c->type != SSH_CHANNEL_ABANDONED)
1.41 markus 2519: packet_disconnect("Received close confirmation for "
2520: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 2521: channel_free(c);
1.339 ! markus 2522: return 0;
1.1 deraadt 2523: }
2524:
1.249 djm 2525: /* ARGSUSED */
1.339 ! markus 2526: int
1.154 markus 2527: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2528: {
1.41 markus 2529: int id, remote_id;
2530: Channel *c;
1.1 deraadt 2531:
1.41 markus 2532: id = packet_get_int();
2533: c = channel_lookup(id);
1.25 markus 2534:
1.41 markus 2535: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2536: packet_disconnect("Received open confirmation for "
2537: "non-opening channel %d.", id);
2538: remote_id = packet_get_int();
1.27 markus 2539: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2540: c->remote_id = remote_id;
2541: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2542:
2543: if (compat20) {
2544: c->remote_window = packet_get_int();
2545: c->remote_maxpacket = packet_get_int();
1.275 djm 2546: if (c->open_confirm) {
1.70 markus 2547: debug2("callback start");
1.304 djm 2548: c->open_confirm(c->self, 1, c->open_confirm_ctx);
1.70 markus 2549: debug2("callback done");
1.44 markus 2550: }
1.194 markus 2551: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
1.44 markus 2552: c->remote_window, c->remote_maxpacket);
2553: }
1.152 markus 2554: packet_check_eom();
1.339 ! markus 2555: return 0;
1.1 deraadt 2556: }
2557:
1.127 itojun 2558: static char *
1.114 markus 2559: reason2txt(int reason)
2560: {
1.143 deraadt 2561: switch (reason) {
1.114 markus 2562: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2563: return "administratively prohibited";
2564: case SSH2_OPEN_CONNECT_FAILED:
2565: return "connect failed";
2566: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2567: return "unknown channel type";
2568: case SSH2_OPEN_RESOURCE_SHORTAGE:
2569: return "resource shortage";
2570: }
1.117 stevesk 2571: return "unknown reason";
1.114 markus 2572: }
2573:
1.249 djm 2574: /* ARGSUSED */
1.339 ! markus 2575: int
1.154 markus 2576: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2577: {
1.86 markus 2578: int id, reason;
2579: char *msg = NULL, *lang = NULL;
1.41 markus 2580: Channel *c;
2581:
2582: id = packet_get_int();
2583: c = channel_lookup(id);
1.25 markus 2584:
1.41 markus 2585: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2586: packet_disconnect("Received open failure for "
2587: "non-opening channel %d.", id);
1.44 markus 2588: if (compat20) {
1.86 markus 2589: reason = packet_get_int();
1.110 markus 2590: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 2591: msg = packet_get_string(NULL);
2592: lang = packet_get_string(NULL);
2593: }
1.188 itojun 2594: logit("channel %d: open failed: %s%s%s", id,
1.114 markus 2595: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.321 djm 2596: free(msg);
2597: free(lang);
1.304 djm 2598: if (c->open_confirm) {
2599: debug2("callback start");
2600: c->open_confirm(c->self, 0, c->open_confirm_ctx);
2601: debug2("callback done");
2602: }
1.44 markus 2603: }
1.152 markus 2604: packet_check_eom();
1.291 djm 2605: /* Schedule the channel for cleanup/deletion. */
2606: chan_mark_dead(c);
1.339 ! markus 2607: return 0;
1.44 markus 2608: }
2609:
1.249 djm 2610: /* ARGSUSED */
1.339 ! markus 2611: int
1.154 markus 2612: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2613: {
2614: Channel *c;
1.178 markus 2615: int id;
2616: u_int adjust;
1.121 markus 2617:
2618: if (!compat20)
1.339 ! markus 2619: return 0;
1.121 markus 2620:
2621: /* Get the channel number and verify it. */
2622: id = packet_get_int();
2623: c = channel_lookup(id);
1.1 deraadt 2624:
1.229 markus 2625: if (c == NULL) {
2626: logit("Received window adjust for non-open channel %d.", id);
1.339 ! markus 2627: return 0;
1.121 markus 2628: }
2629: adjust = packet_get_int();
1.152 markus 2630: packet_check_eom();
1.178 markus 2631: debug2("channel %d: rcvd adjust %u", id, adjust);
1.121 markus 2632: c->remote_window += adjust;
1.339 ! markus 2633: return 0;
1.121 markus 2634: }
1.1 deraadt 2635:
1.249 djm 2636: /* ARGSUSED */
1.339 ! markus 2637: int
1.154 markus 2638: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2639: {
1.121 markus 2640: Channel *c = NULL;
2641: u_short host_port;
2642: char *host, *originator_string;
1.276 djm 2643: int remote_id;
1.121 markus 2644:
2645: remote_id = packet_get_int();
2646: host = packet_get_string(NULL);
2647: host_port = packet_get_int();
1.25 markus 2648:
1.121 markus 2649: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2650: originator_string = packet_get_string(NULL);
2651: } else {
2652: originator_string = xstrdup("unknown (remote did not supply name)");
2653: }
1.152 markus 2654: packet_check_eom();
1.336 millert 2655: c = channel_connect_to_port(host, host_port,
1.276 djm 2656: "connected socket", originator_string);
1.321 djm 2657: free(originator_string);
2658: free(host);
1.121 markus 2659: if (c == NULL) {
2660: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2661: packet_put_int(remote_id);
2662: packet_send();
1.276 djm 2663: } else
2664: c->remote_id = remote_id;
1.339 ! markus 2665: return 0;
1.1 deraadt 2666: }
2667:
1.275 djm 2668: /* ARGSUSED */
1.339 ! markus 2669: int
1.275 djm 2670: channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
2671: {
2672: Channel *c;
2673: struct channel_confirm *cc;
1.289 markus 2674: int id;
1.275 djm 2675:
2676: /* Reset keepalive timeout */
1.296 andreas 2677: packet_set_alive_timeouts(0);
1.275 djm 2678:
1.289 markus 2679: id = packet_get_int();
1.275 djm 2680: packet_check_eom();
2681:
1.289 markus 2682: debug2("channel_input_status_confirm: type %d id %d", type, id);
1.275 djm 2683:
1.289 markus 2684: if ((c = channel_lookup(id)) == NULL) {
2685: logit("channel_input_status_confirm: %d: unknown", id);
1.339 ! markus 2686: return 0;
1.275 djm 2687: }
2688: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 ! markus 2689: return 0;
1.275 djm 2690: cc->cb(type, c, cc->ctx);
2691: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 2692: explicit_bzero(cc, sizeof(*cc));
1.321 djm 2693: free(cc);
1.339 ! markus 2694: return 0;
1.275 djm 2695: }
1.121 markus 2696:
2697: /* -- tcp forwarding */
1.135 markus 2698:
2699: void
2700: channel_set_af(int af)
2701: {
2702: IPv4or6 = af;
2703: }
1.121 markus 2704:
1.312 djm 2705:
2706: /*
2707: * Determine whether or not a port forward listens to loopback, the
2708: * specified address or wildcard. On the client, a specified bind
2709: * address will always override gateway_ports. On the server, a
2710: * gateway_ports of 1 (``yes'') will override the client's specification
2711: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
2712: * will bind to whatever address the client asked for.
2713: *
2714: * Special-case listen_addrs are:
2715: *
2716: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2717: * "" (empty string), "*" -> wildcard v4/v6
2718: * "localhost" -> loopback v4/v6
1.334 djm 2719: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 2720: */
2721: static const char *
2722: channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
1.336 millert 2723: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 2724: {
2725: const char *addr = NULL;
2726: int wildcard = 0;
2727:
2728: if (listen_addr == NULL) {
2729: /* No address specified: default to gateway_ports setting */
1.336 millert 2730: if (fwd_opts->gateway_ports)
1.312 djm 2731: wildcard = 1;
1.336 millert 2732: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 2733: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
2734: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
2735: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 2736: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 2737: wildcard = 1;
1.326 djm 2738: /*
2739: * Notify client if they requested a specific listen
2740: * address and it was overridden.
2741: */
2742: if (*listen_addr != '\0' &&
2743: strcmp(listen_addr, "0.0.0.0") != 0 &&
2744: strcmp(listen_addr, "*") != 0) {
2745: packet_send_debug("Forwarding listen address "
2746: "\"%s\" overridden by server "
2747: "GatewayPorts", listen_addr);
2748: }
1.334 djm 2749: } else if (strcmp(listen_addr, "localhost") != 0 ||
2750: strcmp(listen_addr, "127.0.0.1") == 0 ||
2751: strcmp(listen_addr, "::1") == 0) {
2752: /* Accept localhost address when GatewayPorts=yes */
2753: addr = listen_addr;
1.326 djm 2754: }
1.334 djm 2755: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
2756: strcmp(listen_addr, "::1") == 0) {
2757: /*
2758: * If a specific IPv4/IPv6 localhost address has been
2759: * requested then accept it even if gateway_ports is in
2760: * effect. This allows the client to prefer IPv4 or IPv6.
2761: */
2762: addr = listen_addr;
1.312 djm 2763: }
2764: if (wildcardp != NULL)
2765: *wildcardp = wildcard;
2766: return addr;
2767: }
2768:
1.160 markus 2769: static int
1.336 millert 2770: channel_setup_fwd_listener_tcpip(int type, struct Forward *fwd,
2771: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.25 markus 2772: {
1.113 markus 2773: Channel *c;
1.226 djm 2774: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2775: struct addrinfo hints, *ai, *aitop;
1.212 djm 2776: const char *host, *addr;
1.35 markus 2777: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 2778: in_port_t *lport_p;
1.25 markus 2779:
1.160 markus 2780: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
1.336 millert 2781: fwd->listen_host : fwd->connect_host;
1.212 djm 2782: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2783:
1.160 markus 2784: if (host == NULL) {
2785: error("No forward host name.");
1.218 markus 2786: return 0;
1.73 markus 2787: }
1.294 djm 2788: if (strlen(host) >= NI_MAXHOST) {
1.87 markus 2789: error("Forward host name too long.");
1.218 markus 2790: return 0;
1.87 markus 2791: }
1.25 markus 2792:
1.312 djm 2793: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.336 millert 2794: addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard,
2795: is_client, fwd_opts);
2796: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 2797: type, wildcard, (addr == NULL) ? "NULL" : addr);
2798:
2799: /*
1.35 markus 2800: * getaddrinfo returns a loopback address if the hostname is
2801: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2802: */
1.35 markus 2803: memset(&hints, 0, sizeof(hints));
2804: hints.ai_family = IPv4or6;
1.212 djm 2805: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2806: hints.ai_socktype = SOCK_STREAM;
1.336 millert 2807: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 2808: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2809: if (addr == NULL) {
2810: /* This really shouldn't happen */
2811: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 2812: ssh_gai_strerror(r));
1.212 djm 2813: } else {
1.336 millert 2814: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 2815: ssh_gai_strerror(r));
1.212 djm 2816: }
1.218 markus 2817: return 0;
1.212 djm 2818: }
1.295 djm 2819: if (allocated_listen_port != NULL)
2820: *allocated_listen_port = 0;
1.35 markus 2821: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 2822: switch (ai->ai_family) {
2823: case AF_INET:
2824: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
2825: sin_port;
2826: break;
2827: case AF_INET6:
2828: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
2829: sin6_port;
2830: break;
2831: default:
1.35 markus 2832: continue;
1.295 djm 2833: }
2834: /*
2835: * If allocating a port for -R forwards, then use the
2836: * same port for all address families.
2837: */
1.336 millert 2838: if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 &&
1.295 djm 2839: allocated_listen_port != NULL && *allocated_listen_port > 0)
2840: *lport_p = htons(*allocated_listen_port);
2841:
1.35 markus 2842: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2843: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 2844: error("%s: getnameinfo failed", __func__);
1.35 markus 2845: continue;
2846: }
2847: /* Create a port to listen for the host. */
1.300 dtucker 2848: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2849: if (sock < 0) {
2850: /* this is no error since kernel may not support ipv6 */
2851: verbose("socket: %.100s", strerror(errno));
2852: continue;
2853: }
1.226 djm 2854:
2855: channel_set_reuseaddr(sock);
1.182 stevesk 2856:
1.295 djm 2857: debug("Local forwarding listening on %s port %s.",
2858: ntop, strport);
1.35 markus 2859:
2860: /* Bind the socket to the address. */
2861: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2862: /* address can be in use ipv6 address is already bound */
2863: verbose("bind: %.100s", strerror(errno));
2864: close(sock);
2865: continue;
2866: }
2867: /* Start listening for connections on the socket. */
1.199 markus 2868: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2869: error("listen: %.100s", strerror(errno));
2870: close(sock);
2871: continue;
2872: }
1.295 djm 2873:
2874: /*
1.336 millert 2875: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 2876: * record what we got.
2877: */
1.336 millert 2878: if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 &&
1.295 djm 2879: allocated_listen_port != NULL &&
2880: *allocated_listen_port == 0) {
2881: *allocated_listen_port = get_sock_port(sock, 1);
2882: debug("Allocated listen port %d",
2883: *allocated_listen_port);
2884: }
2885:
1.35 markus 2886: /* Allocate a channel number for the socket. */
1.121 markus 2887: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2888: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2889: 0, "port listener", 1);
1.293 djm 2890: c->path = xstrdup(host);
1.336 millert 2891: c->host_port = fwd->connect_port;
1.312 djm 2892: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 2893: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 2894: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
2895: c->listening_port = *allocated_listen_port;
2896: else
1.336 millert 2897: c->listening_port = fwd->listen_port;
1.35 markus 2898: success = 1;
2899: }
2900: if (success == 0)
1.336 millert 2901: error("%s: cannot listen to port: %d", __func__,
2902: fwd->listen_port);
1.35 markus 2903: freeaddrinfo(aitop);
1.87 markus 2904: return success;
1.25 markus 2905: }
1.1 deraadt 2906:
1.336 millert 2907: static int
2908: channel_setup_fwd_listener_streamlocal(int type, struct Forward *fwd,
2909: struct ForwardOptions *fwd_opts)
2910: {
2911: struct sockaddr_un sunaddr;
2912: const char *path;
2913: Channel *c;
2914: int port, sock;
2915: mode_t omask;
2916:
2917: switch (type) {
2918: case SSH_CHANNEL_UNIX_LISTENER:
2919: if (fwd->connect_path != NULL) {
2920: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
2921: error("Local connecting path too long: %s",
2922: fwd->connect_path);
2923: return 0;
2924: }
2925: path = fwd->connect_path;
2926: port = PORT_STREAMLOCAL;
2927: } else {
2928: if (fwd->connect_host == NULL) {
2929: error("No forward host name.");
2930: return 0;
2931: }
2932: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
2933: error("Forward host name too long.");
2934: return 0;
2935: }
2936: path = fwd->connect_host;
2937: port = fwd->connect_port;
2938: }
2939: break;
2940: case SSH_CHANNEL_RUNIX_LISTENER:
2941: path = fwd->listen_path;
2942: port = PORT_STREAMLOCAL;
2943: break;
2944: default:
2945: error("%s: unexpected channel type %d", __func__, type);
2946: return 0;
2947: }
2948:
2949: if (fwd->listen_path == NULL) {
2950: error("No forward path name.");
2951: return 0;
2952: }
2953: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
2954: error("Local listening path too long: %s", fwd->listen_path);
2955: return 0;
2956: }
2957:
2958: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
2959:
2960: /* Start a Unix domain listener. */
2961: omask = umask(fwd_opts->streamlocal_bind_mask);
2962: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
2963: fwd_opts->streamlocal_bind_unlink);
2964: umask(omask);
2965: if (sock < 0)
2966: return 0;
2967:
2968: debug("Local forwarding listening on path %s.", fwd->listen_path);
2969:
2970: /* Allocate a channel number for the socket. */
2971: c = channel_new("unix listener", type, sock, sock, -1,
2972: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
2973: 0, "unix listener", 1);
2974: c->path = xstrdup(path);
2975: c->host_port = port;
2976: c->listening_port = PORT_STREAMLOCAL;
2977: c->listening_addr = xstrdup(fwd->listen_path);
2978: return 1;
2979: }
2980:
2981: static int
2982: channel_cancel_rport_listener_tcpip(const char *host, u_short port)
1.202 djm 2983: {
1.209 avsm 2984: u_int i;
2985: int found = 0;
1.202 djm 2986:
1.213 deraadt 2987: for (i = 0; i < channels_alloc; i++) {
1.202 djm 2988: Channel *c = channels[i];
1.312 djm 2989: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
2990: continue;
2991: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
2992: debug2("%s: close channel %d", __func__, i);
2993: channel_free(c);
2994: found = 1;
2995: }
2996: }
2997:
2998: return (found);
2999: }
3000:
1.336 millert 3001: static int
3002: channel_cancel_rport_listener_streamlocal(const char *path)
3003: {
3004: u_int i;
3005: int found = 0;
3006:
3007: for (i = 0; i < channels_alloc; i++) {
3008: Channel *c = channels[i];
3009: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3010: continue;
3011: if (c->path == NULL)
3012: continue;
3013: if (strcmp(c->path, path) == 0) {
3014: debug2("%s: close channel %d", __func__, i);
3015: channel_free(c);
3016: found = 1;
3017: }
3018: }
3019:
3020: return (found);
3021: }
3022:
1.312 djm 3023: int
1.336 millert 3024: channel_cancel_rport_listener(struct Forward *fwd)
3025: {
3026: if (fwd->listen_path != NULL)
3027: return channel_cancel_rport_listener_streamlocal(fwd->listen_path);
3028: else
3029: return channel_cancel_rport_listener_tcpip(fwd->listen_host, fwd->listen_port);
3030: }
3031:
3032: static int
3033: channel_cancel_lport_listener_tcpip(const char *lhost, u_short lport,
3034: int cport, struct ForwardOptions *fwd_opts)
1.312 djm 3035: {
3036: u_int i;
3037: int found = 0;
1.336 millert 3038: const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts);
1.202 djm 3039:
1.312 djm 3040: for (i = 0; i < channels_alloc; i++) {
3041: Channel *c = channels[i];
3042: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3043: continue;
1.313 markus 3044: if (c->listening_port != lport)
1.312 djm 3045: continue;
1.313 markus 3046: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3047: /* skip dynamic forwardings */
3048: if (c->host_port == 0)
3049: continue;
3050: } else {
3051: if (c->host_port != cport)
3052: continue;
3053: }
1.312 djm 3054: if ((c->listening_addr == NULL && addr != NULL) ||
3055: (c->listening_addr != NULL && addr == NULL))
3056: continue;
3057: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3058: debug2("%s: close channel %d", __func__, i);
1.202 djm 3059: channel_free(c);
3060: found = 1;
3061: }
3062: }
3063:
3064: return (found);
3065: }
3066:
1.336 millert 3067: static int
3068: channel_cancel_lport_listener_streamlocal(const char *path)
3069: {
3070: u_int i;
3071: int found = 0;
3072:
3073: if (path == NULL) {
3074: error("%s: no path specified.", __func__);
3075: return 0;
3076: }
3077:
3078: for (i = 0; i < channels_alloc; i++) {
3079: Channel *c = channels[i];
3080: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3081: continue;
3082: if (c->listening_addr == NULL)
3083: continue;
3084: if (strcmp(c->listening_addr, path) == 0) {
3085: debug2("%s: close channel %d", __func__, i);
3086: channel_free(c);
3087: found = 1;
3088: }
3089: }
3090:
3091: return (found);
3092: }
3093:
3094: int
3095: channel_cancel_lport_listener(struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
3096: {
3097: if (fwd->listen_path != NULL)
3098: return channel_cancel_lport_listener_streamlocal(fwd->listen_path);
3099: else
3100: return channel_cancel_lport_listener_tcpip(fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3101: }
3102:
1.160 markus 3103: /* protocol local port fwd, used by ssh (and sshd in v1) */
3104: int
1.336 millert 3105: channel_setup_local_fwd_listener(struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3106: {
1.336 millert 3107: if (fwd->listen_path != NULL) {
3108: return channel_setup_fwd_listener_streamlocal(
3109: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3110: } else {
3111: return channel_setup_fwd_listener_tcpip(SSH_CHANNEL_PORT_LISTENER,
3112: fwd, NULL, fwd_opts);
3113: }
1.160 markus 3114: }
3115:
3116: /* protocol v2 remote port fwd, used by sshd */
3117: int
1.336 millert 3118: channel_setup_remote_fwd_listener(struct Forward *fwd,
3119: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3120: {
1.336 millert 3121: if (fwd->listen_path != NULL) {
3122: return channel_setup_fwd_listener_streamlocal(
3123: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3124: } else {
3125: return channel_setup_fwd_listener_tcpip(
3126: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3127: fwd_opts);
3128: }
1.160 markus 3129: }
3130:
1.27 markus 3131: /*
1.312 djm 3132: * Translate the requested rfwd listen host to something usable for
3133: * this server.
3134: */
3135: static const char *
3136: channel_rfwd_bind_host(const char *listen_host)
3137: {
3138: if (listen_host == NULL) {
3139: if (datafellows & SSH_BUG_RFWD_ADDR)
3140: return "127.0.0.1";
3141: else
3142: return "localhost";
3143: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
3144: if (datafellows & SSH_BUG_RFWD_ADDR)
3145: return "0.0.0.0";
3146: else
3147: return "";
3148: } else
3149: return listen_host;
3150: }
3151:
3152: /*
1.27 markus 3153: * Initiate forwarding of connections to port "port" on remote host through
3154: * the secure channel to host:port from local side.
1.315 markus 3155: * Returns handle (index) for updating the dynamic listen port with
3156: * channel_update_permitted_opens().
1.27 markus 3157: */
1.253 markus 3158: int
1.336 millert 3159: channel_request_remote_forwarding(struct Forward *fwd)
1.25 markus 3160: {
1.315 markus 3161: int type, success = 0, idx = -1;
1.73 markus 3162:
1.25 markus 3163: /* Send the forward request to the remote side. */
1.44 markus 3164: if (compat20) {
3165: packet_start(SSH2_MSG_GLOBAL_REQUEST);
1.336 millert 3166: if (fwd->listen_path != NULL) {
3167: packet_put_cstring("streamlocal-forward@openssh.com");
3168: packet_put_char(1); /* boolean: want reply */
3169: packet_put_cstring(fwd->listen_path);
3170: } else {
3171: packet_put_cstring("tcpip-forward");
3172: packet_put_char(1); /* boolean: want reply */
3173: packet_put_cstring(channel_rfwd_bind_host(fwd->listen_host));
3174: packet_put_int(fwd->listen_port);
3175: }
1.73 markus 3176: packet_send();
3177: packet_write_wait();
3178: /* Assume that server accepts the request */
3179: success = 1;
1.336 millert 3180: } else if (fwd->listen_path == NULL) {
1.44 markus 3181: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.336 millert 3182: packet_put_int(fwd->listen_port);
3183: packet_put_cstring(fwd->connect_host);
3184: packet_put_int(fwd->connect_port);
1.44 markus 3185: packet_send();
3186: packet_write_wait();
1.73 markus 3187:
3188: /* Wait for response from the remote side. */
1.153 markus 3189: type = packet_read();
1.73 markus 3190: switch (type) {
3191: case SSH_SMSG_SUCCESS:
3192: success = 1;
3193: break;
3194: case SSH_SMSG_FAILURE:
3195: break;
3196: default:
3197: /* Unknown packet */
3198: packet_disconnect("Protocol error for port forward request:"
3199: "received packet type %d.", type);
3200: }
1.336 millert 3201: } else {
3202: logit("Warning: Server does not support remote stream local forwarding.");
1.73 markus 3203: }
3204: if (success) {
1.305 djm 3205: /* Record that connection to this host/port is permitted. */
3206: permitted_opens = xrealloc(permitted_opens,
3207: num_permitted_opens + 1, sizeof(*permitted_opens));
1.315 markus 3208: idx = num_permitted_opens++;
1.336 millert 3209: if (fwd->connect_path != NULL) {
3210: permitted_opens[idx].host_to_connect =
3211: xstrdup(fwd->connect_path);
3212: permitted_opens[idx].port_to_connect =
3213: PORT_STREAMLOCAL;
3214: } else {
3215: permitted_opens[idx].host_to_connect =
3216: xstrdup(fwd->connect_host);
3217: permitted_opens[idx].port_to_connect =
3218: fwd->connect_port;
3219: }
3220: if (fwd->listen_path != NULL) {
3221: permitted_opens[idx].listen_host = NULL;
3222: permitted_opens[idx].listen_path =
3223: xstrdup(fwd->listen_path);
3224: permitted_opens[idx].listen_port = PORT_STREAMLOCAL;
3225: } else {
3226: permitted_opens[idx].listen_host =
3227: fwd->listen_host ? xstrdup(fwd->listen_host) : NULL;
3228: permitted_opens[idx].listen_path = NULL;
3229: permitted_opens[idx].listen_port = fwd->listen_port;
3230: }
1.44 markus 3231: }
1.315 markus 3232: return (idx);
1.1 deraadt 3233: }
3234:
1.333 markus 3235: static int
3236: open_match(ForwardPermission *allowed_open, const char *requestedhost,
1.336 millert 3237: int requestedport)
1.333 markus 3238: {
3239: if (allowed_open->host_to_connect == NULL)
3240: return 0;
3241: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3242: allowed_open->port_to_connect != requestedport)
3243: return 0;
3244: if (strcmp(allowed_open->host_to_connect, requestedhost) != 0)
3245: return 0;
3246: return 1;
3247: }
3248:
3249: /*
1.336 millert 3250: * Note that in the listen host/port case
1.333 markus 3251: * we don't support FWD_PERMIT_ANY_PORT and
3252: * need to translate between the configured-host (listen_host)
3253: * and what we've sent to the remote server (channel_rfwd_bind_host)
3254: */
3255: static int
1.336 millert 3256: open_listen_match_tcpip(ForwardPermission *allowed_open,
3257: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3258: {
3259: const char *allowed_host;
3260:
3261: if (allowed_open->host_to_connect == NULL)
3262: return 0;
3263: if (allowed_open->listen_port != requestedport)
3264: return 0;
1.335 djm 3265: if (!translate && allowed_open->listen_host == NULL &&
3266: requestedhost == NULL)
3267: return 1;
1.333 markus 3268: allowed_host = translate ?
3269: channel_rfwd_bind_host(allowed_open->listen_host) :
3270: allowed_open->listen_host;
3271: if (allowed_host == NULL ||
3272: strcmp(allowed_host, requestedhost) != 0)
3273: return 0;
3274: return 1;
3275: }
3276:
1.336 millert 3277: static int
3278: open_listen_match_streamlocal(ForwardPermission *allowed_open,
3279: const char *requestedpath)
3280: {
3281: if (allowed_open->host_to_connect == NULL)
3282: return 0;
3283: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3284: return 0;
3285: if (allowed_open->listen_path == NULL ||
3286: strcmp(allowed_open->listen_path, requestedpath) != 0)
3287: return 0;
3288: return 1;
3289: }
3290:
1.27 markus 3291: /*
1.208 deraadt 3292: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3293: * local side.
3294: */
1.336 millert 3295: static int
3296: channel_request_rforward_cancel_tcpip(const char *host, u_short port)
1.202 djm 3297: {
3298: int i;
3299:
3300: if (!compat20)
1.312 djm 3301: return -1;
1.202 djm 3302:
3303: for (i = 0; i < num_permitted_opens; i++) {
1.336 millert 3304: if (open_listen_match_tcpip(&permitted_opens[i], host, port, 0))
1.202 djm 3305: break;
3306: }
3307: if (i >= num_permitted_opens) {
3308: debug("%s: requested forward not found", __func__);
1.312 djm 3309: return -1;
1.202 djm 3310: }
3311: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3312: packet_put_cstring("cancel-tcpip-forward");
3313: packet_put_char(0);
1.312 djm 3314: packet_put_cstring(channel_rfwd_bind_host(host));
1.202 djm 3315: packet_put_int(port);
3316: packet_send();
3317:
1.336 millert 3318: permitted_opens[i].listen_port = 0;
1.333 markus 3319: permitted_opens[i].port_to_connect = 0;
1.336 millert 3320: free(permitted_opens[i].host_to_connect);
3321: permitted_opens[i].host_to_connect = NULL;
3322: free(permitted_opens[i].listen_host);
3323: permitted_opens[i].listen_host = NULL;
3324: permitted_opens[i].listen_path = NULL;
3325:
3326: return 0;
3327: }
3328:
3329: /*
3330: * Request cancellation of remote forwarding of Unix domain socket
3331: * path from local side.
3332: */
3333: static int
3334: channel_request_rforward_cancel_streamlocal(const char *path)
3335: {
3336: int i;
3337:
3338: if (!compat20)
3339: return -1;
3340:
3341: for (i = 0; i < num_permitted_opens; i++) {
3342: if (open_listen_match_streamlocal(&permitted_opens[i], path))
3343: break;
3344: }
3345: if (i >= num_permitted_opens) {
3346: debug("%s: requested forward not found", __func__);
3347: return -1;
3348: }
3349: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3350: packet_put_cstring("cancel-streamlocal-forward@openssh.com");
3351: packet_put_char(0);
3352: packet_put_cstring(path);
3353: packet_send();
3354:
1.202 djm 3355: permitted_opens[i].listen_port = 0;
1.336 millert 3356: permitted_opens[i].port_to_connect = 0;
1.321 djm 3357: free(permitted_opens[i].host_to_connect);
1.202 djm 3358: permitted_opens[i].host_to_connect = NULL;
1.333 markus 3359: permitted_opens[i].listen_host = NULL;
1.336 millert 3360: free(permitted_opens[i].listen_path);
3361: permitted_opens[i].listen_path = NULL;
1.312 djm 3362:
3363: return 0;
1.202 djm 3364: }
3365:
3366: /*
1.336 millert 3367: * Request cancellation of remote forwarding of a connection from local side.
3368: */
3369: int
3370: channel_request_rforward_cancel(struct Forward *fwd)
3371: {
3372: if (fwd->listen_path != NULL) {
3373: return (channel_request_rforward_cancel_streamlocal(
3374: fwd->listen_path));
3375: } else {
3376: return (channel_request_rforward_cancel_tcpip(fwd->listen_host,
3377: fwd->listen_port ? fwd->listen_port : fwd->allocated_port));
3378: }
3379: }
3380:
3381: /*
1.27 markus 3382: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
3383: * listening for the port, and sends back a success reply (or disconnect
1.253 markus 3384: * message if there was an error).
1.27 markus 3385: */
1.253 markus 3386: int
1.336 millert 3387: channel_input_port_forward_request(int is_root, struct ForwardOptions *fwd_opts)
1.1 deraadt 3388: {
1.253 markus 3389: int success = 0;
1.336 millert 3390: struct Forward fwd;
1.1 deraadt 3391:
1.25 markus 3392: /* Get arguments from the packet. */
1.336 millert 3393: memset(&fwd, 0, sizeof(fwd));
3394: fwd.listen_port = packet_get_int();
3395: fwd.connect_host = packet_get_string(NULL);
3396: fwd.connect_port = packet_get_int();
1.25 markus 3397:
1.27 markus 3398: /*
3399: * Check that an unprivileged user is not trying to forward a
3400: * privileged port.
3401: */
1.336 millert 3402: if (fwd.listen_port < IPPORT_RESERVED && !is_root)
1.192 markus 3403: packet_disconnect(
3404: "Requested forwarding of port %d but user is not root.",
1.336 millert 3405: fwd.listen_port);
3406: if (fwd.connect_port == 0)
1.192 markus 3407: packet_disconnect("Dynamic forwarding denied.");
3408:
1.73 markus 3409: /* Initiate forwarding */
1.336 millert 3410: success = channel_setup_local_fwd_listener(&fwd, fwd_opts);
1.25 markus 3411:
3412: /* Free the argument string. */
1.336 millert 3413: free(fwd.connect_host);
1.253 markus 3414:
3415: return (success ? 0 : -1);
1.1 deraadt 3416: }
3417:
1.99 markus 3418: /*
3419: * Permits opening to any host/port if permitted_opens[] is empty. This is
3420: * usually called by the server, because the user could connect to any port
3421: * anyway, and the server has no way to know but to trust the client anyway.
3422: */
3423: void
1.142 itojun 3424: channel_permit_all_opens(void)
1.99 markus 3425: {
3426: if (num_permitted_opens == 0)
3427: all_opens_permitted = 1;
3428: }
3429:
1.101 markus 3430: void
1.99 markus 3431: channel_add_permitted_opens(char *host, int port)
3432: {
3433: debug("allow port forwarding to host %s port %d", host, port);
3434:
1.305 djm 3435: permitted_opens = xrealloc(permitted_opens,
3436: num_permitted_opens + 1, sizeof(*permitted_opens));
1.99 markus 3437: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
3438: permitted_opens[num_permitted_opens].port_to_connect = port;
1.333 markus 3439: permitted_opens[num_permitted_opens].listen_host = NULL;
1.336 millert 3440: permitted_opens[num_permitted_opens].listen_path = NULL;
1.333 markus 3441: permitted_opens[num_permitted_opens].listen_port = 0;
1.99 markus 3442: num_permitted_opens++;
3443:
3444: all_opens_permitted = 0;
1.315 markus 3445: }
3446:
3447: /*
3448: * Update the listen port for a dynamic remote forward, after
3449: * the actual 'newport' has been allocated. If 'newport' < 0 is
3450: * passed then they entry will be invalidated.
3451: */
3452: void
3453: channel_update_permitted_opens(int idx, int newport)
3454: {
3455: if (idx < 0 || idx >= num_permitted_opens) {
3456: debug("channel_update_permitted_opens: index out of range:"
3457: " %d num_permitted_opens %d", idx, num_permitted_opens);
3458: return;
3459: }
3460: debug("%s allowed port %d for forwarding to host %s port %d",
3461: newport > 0 ? "Updating" : "Removing",
3462: newport,
3463: permitted_opens[idx].host_to_connect,
3464: permitted_opens[idx].port_to_connect);
3465: if (newport >= 0) {
3466: permitted_opens[idx].listen_port =
3467: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
3468: } else {
3469: permitted_opens[idx].listen_port = 0;
3470: permitted_opens[idx].port_to_connect = 0;
1.321 djm 3471: free(permitted_opens[idx].host_to_connect);
1.315 markus 3472: permitted_opens[idx].host_to_connect = NULL;
1.333 markus 3473: free(permitted_opens[idx].listen_host);
3474: permitted_opens[idx].listen_host = NULL;
1.336 millert 3475: free(permitted_opens[idx].listen_path);
3476: permitted_opens[idx].listen_path = NULL;
1.315 markus 3477: }
1.99 markus 3478: }
3479:
1.258 dtucker 3480: int
1.257 dtucker 3481: channel_add_adm_permitted_opens(char *host, int port)
3482: {
1.258 dtucker 3483: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 3484:
1.305 djm 3485: permitted_adm_opens = xrealloc(permitted_adm_opens,
3486: num_adm_permitted_opens + 1, sizeof(*permitted_adm_opens));
1.257 dtucker 3487: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
3488: = xstrdup(host);
3489: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.333 markus 3490: permitted_adm_opens[num_adm_permitted_opens].listen_host = NULL;
1.336 millert 3491: permitted_adm_opens[num_adm_permitted_opens].listen_path = NULL;
1.333 markus 3492: permitted_adm_opens[num_adm_permitted_opens].listen_port = 0;
1.258 dtucker 3493: return ++num_adm_permitted_opens;
1.257 dtucker 3494: }
3495:
3496: void
1.316 dtucker 3497: channel_disable_adm_local_opens(void)
3498: {
1.319 djm 3499: channel_clear_adm_permitted_opens();
3500: permitted_adm_opens = xmalloc(sizeof(*permitted_adm_opens));
3501: permitted_adm_opens[num_adm_permitted_opens].host_to_connect = NULL;
3502: num_adm_permitted_opens = 1;
1.316 dtucker 3503: }
3504:
3505: void
1.99 markus 3506: channel_clear_permitted_opens(void)
3507: {
3508: int i;
3509:
1.333 markus 3510: for (i = 0; i < num_permitted_opens; i++) {
1.321 djm 3511: free(permitted_opens[i].host_to_connect);
1.333 markus 3512: free(permitted_opens[i].listen_host);
1.336 millert 3513: free(permitted_opens[i].listen_path);
1.333 markus 3514: }
1.321 djm 3515: free(permitted_opens);
3516: permitted_opens = NULL;
1.99 markus 3517: num_permitted_opens = 0;
1.257 dtucker 3518: }
3519:
3520: void
3521: channel_clear_adm_permitted_opens(void)
3522: {
3523: int i;
1.99 markus 3524:
1.333 markus 3525: for (i = 0; i < num_adm_permitted_opens; i++) {
1.321 djm 3526: free(permitted_adm_opens[i].host_to_connect);
1.333 markus 3527: free(permitted_adm_opens[i].listen_host);
1.336 millert 3528: free(permitted_adm_opens[i].listen_path);
1.333 markus 3529: }
1.321 djm 3530: free(permitted_adm_opens);
3531: permitted_adm_opens = NULL;
1.257 dtucker 3532: num_adm_permitted_opens = 0;
1.278 dtucker 3533: }
3534:
3535: void
3536: channel_print_adm_permitted_opens(void)
3537: {
1.286 djm 3538: int i;
1.278 dtucker 3539:
1.290 stevesk 3540: printf("permitopen");
1.288 stevesk 3541: if (num_adm_permitted_opens == 0) {
1.290 stevesk 3542: printf(" any\n");
1.288 stevesk 3543: return;
3544: }
1.278 dtucker 3545: for (i = 0; i < num_adm_permitted_opens; i++)
1.316 dtucker 3546: if (permitted_adm_opens[i].host_to_connect == NULL)
3547: printf(" none");
3548: else
1.278 dtucker 3549: printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
3550: permitted_adm_opens[i].port_to_connect);
1.290 stevesk 3551: printf("\n");
1.99 markus 3552: }
3553:
1.314 dtucker 3554: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3555: int
3556: permitopen_port(const char *p)
3557: {
3558: int port;
3559:
3560: if (strcmp(p, "*") == 0)
3561: return FWD_PERMIT_ANY_PORT;
3562: if ((port = a2port(p)) > 0)
3563: return port;
3564: return -1;
3565: }
3566:
1.276 djm 3567: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 3568: static int
1.276 djm 3569: connect_next(struct channel_connect *cctx)
1.41 markus 3570: {
1.276 djm 3571: int sock, saved_errno;
1.336 millert 3572: struct sockaddr_un *sunaddr;
3573: char ntop[NI_MAXHOST], strport[MAX(NI_MAXSERV,sizeof(sunaddr->sun_path))];
1.41 markus 3574:
1.276 djm 3575: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 3576: switch (cctx->ai->ai_family) {
3577: case AF_UNIX:
3578: /* unix:pathname instead of host:port */
3579: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
3580: strlcpy(ntop, "unix", sizeof(ntop));
3581: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
3582: break;
3583: case AF_INET:
3584: case AF_INET6:
3585: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
3586: ntop, sizeof(ntop), strport, sizeof(strport),
3587: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
3588: error("connect_next: getnameinfo failed");
3589: continue;
3590: }
3591: break;
3592: default:
1.41 markus 3593: continue;
3594: }
1.300 dtucker 3595: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
3596: cctx->ai->ai_protocol)) == -1) {
1.276 djm 3597: if (cctx->ai->ai_next == NULL)
1.186 djm 3598: error("socket: %.100s", strerror(errno));
3599: else
3600: verbose("socket: %.100s", strerror(errno));
1.41 markus 3601: continue;
3602: }
1.205 djm 3603: if (set_nonblock(sock) == -1)
3604: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 3605: if (connect(sock, cctx->ai->ai_addr,
3606: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
3607: debug("connect_next: host %.100s ([%.100s]:%s): "
3608: "%.100s", cctx->host, ntop, strport,
1.41 markus 3609: strerror(errno));
1.276 djm 3610: saved_errno = errno;
1.41 markus 3611: close(sock);
1.276 djm 3612: errno = saved_errno;
1.89 stevesk 3613: continue; /* fail -- try next */
1.41 markus 3614: }
1.336 millert 3615: if (cctx->ai->ai_family != AF_UNIX)
3616: set_nodelay(sock);
1.276 djm 3617: debug("connect_next: host %.100s ([%.100s]:%s) "
3618: "in progress, fd=%d", cctx->host, ntop, strport, sock);
3619: cctx->ai = cctx->ai->ai_next;
3620: return sock;
3621: }
3622: return -1;
3623: }
1.41 markus 3624:
1.276 djm 3625: static void
3626: channel_connect_ctx_free(struct channel_connect *cctx)
3627: {
1.321 djm 3628: free(cctx->host);
1.336 millert 3629: if (cctx->aitop) {
3630: if (cctx->aitop->ai_family == AF_UNIX)
3631: free(cctx->aitop);
3632: else
3633: freeaddrinfo(cctx->aitop);
3634: }
1.329 tedu 3635: memset(cctx, 0, sizeof(*cctx));
1.276 djm 3636: }
3637:
1.336 millert 3638: /* Return CONNECTING channel to remote host:port or local socket path */
1.276 djm 3639: static Channel *
1.336 millert 3640: connect_to(const char *name, int port, char *ctype, char *rname)
1.276 djm 3641: {
3642: struct addrinfo hints;
3643: int gaierr;
3644: int sock = -1;
3645: char strport[NI_MAXSERV];
3646: struct channel_connect cctx;
3647: Channel *c;
3648:
1.284 djm 3649: memset(&cctx, 0, sizeof(cctx));
1.336 millert 3650:
3651: if (port == PORT_STREAMLOCAL) {
3652: struct sockaddr_un *sunaddr;
3653: struct addrinfo *ai;
3654:
3655: if (strlen(name) > sizeof(sunaddr->sun_path)) {
3656: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
3657: return (NULL);
3658: }
3659:
3660: /*
3661: * Fake up a struct addrinfo for AF_UNIX connections.
3662: * channel_connect_ctx_free() must check ai_family
3663: * and use free() not freeaddirinfo() for AF_UNIX.
3664: */
3665: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
3666: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
3667: ai->ai_addr = (struct sockaddr *)(ai + 1);
3668: ai->ai_addrlen = sizeof(*sunaddr);
3669: ai->ai_family = AF_UNIX;
3670: ai->ai_socktype = SOCK_STREAM;
3671: ai->ai_protocol = PF_UNSPEC;
3672: sunaddr = (struct sockaddr_un *)ai->ai_addr;
3673: sunaddr->sun_family = AF_UNIX;
3674: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
3675: cctx.aitop = ai;
3676: } else {
3677: memset(&hints, 0, sizeof(hints));
3678: hints.ai_family = IPv4or6;
3679: hints.ai_socktype = SOCK_STREAM;
3680: snprintf(strport, sizeof strport, "%d", port);
3681: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx.aitop)) != 0) {
3682: error("connect_to %.100s: unknown host (%s)", name,
3683: ssh_gai_strerror(gaierr));
3684: return NULL;
3685: }
1.41 markus 3686: }
1.276 djm 3687:
1.336 millert 3688: cctx.host = xstrdup(name);
1.276 djm 3689: cctx.port = port;
3690: cctx.ai = cctx.aitop;
3691:
3692: if ((sock = connect_next(&cctx)) == -1) {
3693: error("connect to %.100s port %d failed: %s",
1.336 millert 3694: name, port, strerror(errno));
1.276 djm 3695: channel_connect_ctx_free(&cctx);
3696: return NULL;
1.41 markus 3697: }
1.276 djm 3698: c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
3699: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
3700: c->connect_ctx = cctx;
3701: return c;
1.41 markus 3702: }
1.99 markus 3703:
1.276 djm 3704: Channel *
1.333 markus 3705: channel_connect_by_listen_address(const char *listen_host,
3706: u_short listen_port, char *ctype, char *rname)
1.73 markus 3707: {
3708: int i;
1.99 markus 3709:
1.276 djm 3710: for (i = 0; i < num_permitted_opens; i++) {
1.336 millert 3711: if (open_listen_match_tcpip(&permitted_opens[i], listen_host,
1.333 markus 3712: listen_port, 1)) {
1.99 markus 3713: return connect_to(
1.73 markus 3714: permitted_opens[i].host_to_connect,
1.276 djm 3715: permitted_opens[i].port_to_connect, ctype, rname);
3716: }
3717: }
1.74 markus 3718: error("WARNING: Server requests forwarding for unknown listen_port %d",
3719: listen_port);
1.276 djm 3720: return NULL;
1.73 markus 3721: }
3722:
1.336 millert 3723: Channel *
3724: channel_connect_by_listen_path(const char *path, char *ctype, char *rname)
3725: {
3726: int i;
3727:
3728: for (i = 0; i < num_permitted_opens; i++) {
3729: if (open_listen_match_streamlocal(&permitted_opens[i], path)) {
3730: return connect_to(
3731: permitted_opens[i].host_to_connect,
3732: permitted_opens[i].port_to_connect, ctype, rname);
3733: }
3734: }
3735: error("WARNING: Server requests forwarding for unknown path %.100s",
3736: path);
3737: return NULL;
3738: }
3739:
1.99 markus 3740: /* Check if connecting to that port is permitted and connect. */
1.276 djm 3741: Channel *
1.336 millert 3742: channel_connect_to_port(const char *host, u_short port, char *ctype, char *rname)
1.99 markus 3743: {
1.257 dtucker 3744: int i, permit, permit_adm = 1;
1.99 markus 3745:
3746: permit = all_opens_permitted;
3747: if (!permit) {
3748: for (i = 0; i < num_permitted_opens; i++)
1.333 markus 3749: if (open_match(&permitted_opens[i], host, port)) {
1.99 markus 3750: permit = 1;
1.333 markus 3751: break;
3752: }
1.257 dtucker 3753: }
1.99 markus 3754:
1.257 dtucker 3755: if (num_adm_permitted_opens > 0) {
3756: permit_adm = 0;
3757: for (i = 0; i < num_adm_permitted_opens; i++)
1.333 markus 3758: if (open_match(&permitted_adm_opens[i], host, port)) {
1.257 dtucker 3759: permit_adm = 1;
1.333 markus 3760: break;
3761: }
1.99 markus 3762: }
1.257 dtucker 3763:
3764: if (!permit || !permit_adm) {
1.188 itojun 3765: logit("Received request to connect to host %.100s port %d, "
1.99 markus 3766: "but the request was denied.", host, port);
1.276 djm 3767: return NULL;
1.99 markus 3768: }
1.276 djm 3769: return connect_to(host, port, ctype, rname);
1.336 millert 3770: }
3771:
3772: /* Check if connecting to that path is permitted and connect. */
3773: Channel *
3774: channel_connect_to_path(const char *path, char *ctype, char *rname)
3775: {
3776: int i, permit, permit_adm = 1;
3777:
3778: permit = all_opens_permitted;
3779: if (!permit) {
3780: for (i = 0; i < num_permitted_opens; i++)
3781: if (open_match(&permitted_opens[i], path, PORT_STREAMLOCAL)) {
3782: permit = 1;
3783: break;
3784: }
3785: }
3786:
3787: if (num_adm_permitted_opens > 0) {
3788: permit_adm = 0;
3789: for (i = 0; i < num_adm_permitted_opens; i++)
3790: if (open_match(&permitted_adm_opens[i], path, PORT_STREAMLOCAL)) {
3791: permit_adm = 1;
3792: break;
3793: }
3794: }
3795:
3796: if (!permit || !permit_adm) {
3797: logit("Received request to connect to path %.100s, "
3798: "but the request was denied.", path);
3799: return NULL;
3800: }
3801: return connect_to(path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 3802: }
3803:
3804: void
3805: channel_send_window_changes(void)
3806: {
1.209 avsm 3807: u_int i;
1.204 djm 3808: struct winsize ws;
3809:
3810: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 3811: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 3812: channels[i]->type != SSH_CHANNEL_OPEN)
3813: continue;
3814: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
3815: continue;
3816: channel_request_start(i, "window-change", 0);
1.238 deraadt 3817: packet_put_int((u_int)ws.ws_col);
3818: packet_put_int((u_int)ws.ws_row);
3819: packet_put_int((u_int)ws.ws_xpixel);
3820: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 3821: packet_send();
3822: }
1.99 markus 3823: }
3824:
1.121 markus 3825: /* -- X11 forwarding */
1.1 deraadt 3826:
1.27 markus 3827: /*
3828: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 3829: * Returns 0 and a suitable display number for the DISPLAY variable
3830: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 3831: */
1.141 stevesk 3832: int
1.163 stevesk 3833: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 3834: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 3835: {
1.149 markus 3836: Channel *nc = NULL;
1.31 markus 3837: int display_number, sock;
3838: u_short port;
1.35 markus 3839: struct addrinfo hints, *ai, *aitop;
3840: char strport[NI_MAXSERV];
3841: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 3842:
1.224 markus 3843: if (chanids == NULL)
3844: return -1;
3845:
1.33 markus 3846: for (display_number = x11_display_offset;
1.148 deraadt 3847: display_number < MAX_DISPLAYS;
3848: display_number++) {
1.25 markus 3849: port = 6000 + display_number;
1.35 markus 3850: memset(&hints, 0, sizeof(hints));
3851: hints.ai_family = IPv4or6;
1.163 stevesk 3852: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 3853: hints.ai_socktype = SOCK_STREAM;
3854: snprintf(strport, sizeof strport, "%d", port);
3855: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3856: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 3857: return -1;
1.25 markus 3858: }
1.35 markus 3859: for (ai = aitop; ai; ai = ai->ai_next) {
3860: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
3861: continue;
1.300 dtucker 3862: sock = socket(ai->ai_family, ai->ai_socktype,
3863: ai->ai_protocol);
1.35 markus 3864: if (sock < 0) {
3865: error("socket: %.100s", strerror(errno));
1.203 markus 3866: freeaddrinfo(aitop);
1.141 stevesk 3867: return -1;
1.35 markus 3868: }
1.226 djm 3869: channel_set_reuseaddr(sock);
1.35 markus 3870: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 3871: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 3872: close(sock);
1.183 itojun 3873:
1.35 markus 3874: for (n = 0; n < num_socks; n++) {
3875: close(socks[n]);
3876: }
3877: num_socks = 0;
3878: break;
3879: }
3880: socks[num_socks++] = sock;
3881: if (num_socks == NUM_SOCKS)
3882: break;
1.25 markus 3883: }
1.83 stevesk 3884: freeaddrinfo(aitop);
1.35 markus 3885: if (num_socks > 0)
3886: break;
1.25 markus 3887: }
3888: if (display_number >= MAX_DISPLAYS) {
3889: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 3890: return -1;
1.25 markus 3891: }
3892: /* Start listening for connections on the socket. */
1.35 markus 3893: for (n = 0; n < num_socks; n++) {
3894: sock = socks[n];
1.199 markus 3895: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3896: error("listen: %.100s", strerror(errno));
3897: close(sock);
1.141 stevesk 3898: return -1;
1.35 markus 3899: }
1.25 markus 3900: }
1.35 markus 3901:
3902: /* Allocate a channel for each socket. */
1.242 djm 3903: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 3904: for (n = 0; n < num_socks; n++) {
3905: sock = socks[n];
1.149 markus 3906: nc = channel_new("x11 listener",
1.51 markus 3907: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
3908: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 3909: 0, "X11 inet listener", 1);
1.167 markus 3910: nc->single_connection = single_connection;
1.224 markus 3911: (*chanids)[n] = nc->self;
1.35 markus 3912: }
1.224 markus 3913: (*chanids)[n] = -1;
1.1 deraadt 3914:
1.141 stevesk 3915: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 3916: *display_numberp = display_number;
3917: return (0);
1.1 deraadt 3918: }
3919:
1.127 itojun 3920: static int
1.77 markus 3921: connect_local_xsocket(u_int dnr)
1.1 deraadt 3922: {
1.25 markus 3923: int sock;
3924: struct sockaddr_un addr;
3925:
1.147 stevesk 3926: sock = socket(AF_UNIX, SOCK_STREAM, 0);
3927: if (sock < 0)
3928: error("socket: %.100s", strerror(errno));
3929: memset(&addr, 0, sizeof(addr));
3930: addr.sun_family = AF_UNIX;
3931: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 3932: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 3933: return sock;
3934: close(sock);
1.25 markus 3935: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
3936: return -1;
1.1 deraadt 3937: }
3938:
1.51 markus 3939: int
3940: x11_connect_display(void)
1.1 deraadt 3941: {
1.248 deraadt 3942: u_int display_number;
1.25 markus 3943: const char *display;
1.51 markus 3944: char buf[1024], *cp;
1.35 markus 3945: struct addrinfo hints, *ai, *aitop;
3946: char strport[NI_MAXSERV];
1.248 deraadt 3947: int gaierr, sock = 0;
1.25 markus 3948:
3949: /* Try to open a socket for the local X server. */
3950: display = getenv("DISPLAY");
3951: if (!display) {
3952: error("DISPLAY not set.");
1.51 markus 3953: return -1;
1.25 markus 3954: }
1.27 markus 3955: /*
3956: * Now we decode the value of the DISPLAY variable and make a
3957: * connection to the real X server.
3958: */
3959:
3960: /*
3961: * Check if it is a unix domain socket. Unix domain displays are in
3962: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3963: */
1.25 markus 3964: if (strncmp(display, "unix:", 5) == 0 ||
3965: display[0] == ':') {
3966: /* Connect to the unix domain socket. */
1.248 deraadt 3967: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 3968: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3969: display);
1.51 markus 3970: return -1;
1.25 markus 3971: }
3972: /* Create a socket. */
3973: sock = connect_local_xsocket(display_number);
3974: if (sock < 0)
1.51 markus 3975: return -1;
1.25 markus 3976:
3977: /* OK, we now have a connection to the display. */
1.51 markus 3978: return sock;
1.25 markus 3979: }
1.27 markus 3980: /*
3981: * Connect to an inet socket. The DISPLAY value is supposedly
3982: * hostname:d[.s], where hostname may also be numeric IP address.
3983: */
1.145 stevesk 3984: strlcpy(buf, display, sizeof(buf));
1.25 markus 3985: cp = strchr(buf, ':');
3986: if (!cp) {
3987: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 3988: return -1;
1.25 markus 3989: }
3990: *cp = 0;
1.27 markus 3991: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 3992: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 3993: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3994: display);
1.51 markus 3995: return -1;
1.25 markus 3996: }
1.35 markus 3997:
3998: /* Look up the host address */
3999: memset(&hints, 0, sizeof(hints));
4000: hints.ai_family = IPv4or6;
4001: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4002: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4003: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4004: error("%.100s: unknown host. (%s)", buf,
4005: ssh_gai_strerror(gaierr));
1.51 markus 4006: return -1;
1.25 markus 4007: }
1.35 markus 4008: for (ai = aitop; ai; ai = ai->ai_next) {
4009: /* Create a socket. */
1.300 dtucker 4010: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 4011: if (sock < 0) {
1.194 markus 4012: debug2("socket: %.100s", strerror(errno));
1.41 markus 4013: continue;
4014: }
4015: /* Connect it to the display. */
4016: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 4017: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4018: 6000 + display_number, strerror(errno));
4019: close(sock);
4020: continue;
4021: }
4022: /* Success */
4023: break;
1.35 markus 4024: }
4025: freeaddrinfo(aitop);
4026: if (!ai) {
1.248 deraadt 4027: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 4028: strerror(errno));
1.51 markus 4029: return -1;
1.25 markus 4030: }
1.162 stevesk 4031: set_nodelay(sock);
1.51 markus 4032: return sock;
4033: }
4034:
4035: /*
4036: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
4037: * the remote channel number. We should do whatever we want, and respond
4038: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
4039: */
4040:
1.259 stevesk 4041: /* ARGSUSED */
1.339 ! markus 4042: int
1.154 markus 4043: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 4044: {
1.113 markus 4045: Channel *c = NULL;
4046: int remote_id, sock = 0;
1.51 markus 4047: char *remote_host;
1.25 markus 4048:
1.113 markus 4049: debug("Received X11 open request.");
1.51 markus 4050:
1.113 markus 4051: remote_id = packet_get_int();
1.121 markus 4052:
4053: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 4054: remote_host = packet_get_string(NULL);
1.51 markus 4055: } else {
4056: remote_host = xstrdup("unknown (remote did not supply name)");
4057: }
1.152 markus 4058: packet_check_eom();
1.25 markus 4059:
1.51 markus 4060: /* Obtain a connection to the real X display. */
4061: sock = x11_connect_display();
1.113 markus 4062: if (sock != -1) {
4063: /* Allocate a channel for this connection. */
4064: c = channel_new("connected x11 socket",
4065: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
4066: remote_host, 1);
1.167 markus 4067: c->remote_id = remote_id;
4068: c->force_drain = 1;
1.113 markus 4069: }
1.321 djm 4070: free(remote_host);
1.113 markus 4071: if (c == NULL) {
1.51 markus 4072: /* Send refusal to the remote host. */
4073: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 4074: packet_put_int(remote_id);
1.51 markus 4075: } else {
4076: /* Send a confirmation to the remote host. */
4077: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 4078: packet_put_int(remote_id);
4079: packet_put_int(c->self);
1.51 markus 4080: }
1.113 markus 4081: packet_send();
1.339 ! markus 4082: return 0;
1.72 markus 4083: }
4084:
4085: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
1.259 stevesk 4086: /* ARGSUSED */
1.339 ! markus 4087: int
1.154 markus 4088: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 4089: {
4090: int rchan = packet_get_int();
1.180 deraadt 4091:
1.143 deraadt 4092: switch (type) {
1.72 markus 4093: case SSH_SMSG_AGENT_OPEN:
4094: error("Warning: ssh server tried agent forwarding.");
4095: break;
4096: case SSH_SMSG_X11_OPEN:
4097: error("Warning: ssh server tried X11 forwarding.");
4098: break;
4099: default:
1.154 markus 4100: error("deny_input_open: type %d", type);
1.72 markus 4101: break;
4102: }
1.230 stevesk 4103: error("Warning: this is probably a break-in attempt by a malicious server.");
1.72 markus 4104: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
4105: packet_put_int(rchan);
4106: packet_send();
1.339 ! markus 4107: return 0;
1.1 deraadt 4108: }
4109:
1.27 markus 4110: /*
4111: * Requests forwarding of X11 connections, generates fake authentication
4112: * data, and enables authentication spoofing.
1.121 markus 4113: * This should be called in the client only.
1.27 markus 4114: */
1.49 markus 4115: void
1.215 djm 4116: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.311 djm 4117: const char *proto, const char *data, int want_reply)
1.1 deraadt 4118: {
1.77 markus 4119: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4120: u_int i, value;
1.25 markus 4121: char *new_data;
4122: int screen_number;
4123: const char *cp;
1.207 avsm 4124: u_int32_t rnd = 0;
1.25 markus 4125:
1.220 markus 4126: if (x11_saved_display == NULL)
4127: x11_saved_display = xstrdup(disp);
4128: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 4129: error("x11_request_forwarding_with_spoofing: different "
4130: "$DISPLAY already forwarded");
4131: return;
4132: }
4133:
1.266 djm 4134: cp = strchr(disp, ':');
1.25 markus 4135: if (cp)
4136: cp = strchr(cp, '.');
4137: if (cp)
1.245 deraadt 4138: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4139: else
4140: screen_number = 0;
4141:
1.219 djm 4142: if (x11_saved_proto == NULL) {
4143: /* Save protocol name. */
4144: x11_saved_proto = xstrdup(proto);
4145: /*
1.221 djm 4146: * Extract real authentication data and generate fake data
1.219 djm 4147: * of the same length.
4148: */
4149: x11_saved_data = xmalloc(data_len);
4150: x11_fake_data = xmalloc(data_len);
4151: for (i = 0; i < data_len; i++) {
4152: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4153: fatal("x11_request_forwarding: bad "
4154: "authentication data: %.100s", data);
4155: if (i % 4 == 0)
4156: rnd = arc4random();
4157: x11_saved_data[i] = value;
4158: x11_fake_data[i] = rnd & 0xff;
4159: rnd >>= 8;
4160: }
4161: x11_saved_data_len = data_len;
4162: x11_fake_data_len = data_len;
1.25 markus 4163: }
4164:
4165: /* Convert the fake data into hex. */
1.219 djm 4166: new_data = tohex(x11_fake_data, data_len);
1.25 markus 4167:
4168: /* Send the request packet. */
1.51 markus 4169: if (compat20) {
1.311 djm 4170: channel_request_start(client_session_id, "x11-req", want_reply);
1.51 markus 4171: packet_put_char(0); /* XXX bool single connection */
4172: } else {
4173: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
4174: }
4175: packet_put_cstring(proto);
4176: packet_put_cstring(new_data);
1.25 markus 4177: packet_put_int(screen_number);
4178: packet_send();
4179: packet_write_wait();
1.321 djm 4180: free(new_data);
1.1 deraadt 4181: }
4182:
1.121 markus 4183:
4184: /* -- agent forwarding */
4185:
1.1 deraadt 4186: /* Sends a message to the server to request authentication fd forwarding. */
4187:
1.49 markus 4188: void
1.142 itojun 4189: auth_request_forwarding(void)
1.1 deraadt 4190: {
1.25 markus 4191: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
4192: packet_send();
4193: packet_write_wait();
1.1 deraadt 4194: }
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